High dietary calcium intakes are unnecessary for prevention of secondary hyperparathyroidism in subjects with 25(OH)D levels above 75 nmol/liter.

Vitamin d deficiency in postmenopausal women - biological correlates.

INTRODUCTION Low vitamin D (VD) is associated with secondary hyperparathyroidism and both contribute to deleterious consequences (reduced bone mineral density (BMD), risk of fractures and falls). OBJECTIVE To study the VD status and biological correlates in a group of postmenopausal women. MATERIAL AND METHODS We studied 123 postmenopausal women evaluated in the C.I.Parhon National Institute of Endocrinology, the Pituitary and Neuroendocrine Diseases department. All cases had been reffered for the evaluation of BMD by the general practitioner. The evaluation included serum measurements of total and ionised calcium, phosphorus, alkaline phosphatase (ALP), 25 hydroxi vitaminD (25OHD), parathyroid hormone (PTH), osteocalcin, betacrosslaps. Central DXA osteodensitometry was performed. RESULTS 91.9% of cases had 25OHD serum levels below 30 ng/ml (74.8% had VD deficiency, 17.1% VD insufficiency). Only 8.1% had sufficient VD levels. A history of fragility fractures was present in 45.83% of the osteoporotic patients, 27.27% of the osteopenic ones and 15.15% of the women with normal BMD. 32 women (26%) were on VD supplementation at the time of evaluation. Among these subjects, the 25OHD level was significantly higher in those with prior fragility fractures (p=0.018) and osteoporosis (p=0.008). 25OHD concentration negatively correlated with PTH, alkaline phosphatase (ALP) and osteocalcin. The bone markers evaluated had a significant inverse correlation with the radius BMD, T and Z scores (p=0.004). 27.17% of the cases with VD deficiency had secondary hyperparathyroidism. The 25OHD concentration was significantly lower in these cases (p=0.000). CONCLUSIONS VD insufficiency is widely prevalent but still under-recognized and under-treated, possibly leading to secondary hyperparathyroidism. The compliance to VD supplementation is lower in subjects without osteoporosis or fragility fractures. Primary prevention measures should be more actively implemented.

Relationship between serum parathyroid hormone levels, vitamin D sufficiency, and calcium intake.

CONTEXT Adequate vitamin D status for optimum bone health has received increased recognition in recent years; however, the ideal intake is not known. Serum 25-hydroxyvitamin D is the generally accepted indicator of vitamin D status, but no universal reference level has been reached. OBJECTIVE To investigate the relative importance of high calcium intake and serum 25-hydroxyvitamin D for calcium homeostasis, as determined by serum intact parathyroid hormone (PTH). DESIGN, SETTING, AND PARTICIPANTS Cross-sectional study of 2310 healthy Icelandic adults who were divided equally into 3 age groups (30-45 years, 50-65 years, or 70-85 years) and recruited from February 2001 to January 2003. They were administered a semi-quantitative food frequency questionnaire, which assessed vitamin D and calcium intake. Participants were further divided into groups according to calcium intake (<800 mg/d, 800-1200 mg/d, and >1200 mg/d) and serum 25-hydroxyvitamin D level (<10 ng/mL, 10-18 ng/mL, and >18 ng/mL). MAIN OUTCOME MEASURE Serum intact PTH as determined by calcium intake and vitamin D.   RESULTS A total of 944 healthy participants completed all parts of the study. After adjusting for relevant factors, serum PTH was lowest in the group with a serum 25-hydroxyvitamin D level of more than 18 ng/mL but highest in the group with a serum 25-hydroxyvitamin D level of less than 10 ng/mL. At the low serum 25-hydroxyvitamin D level (<10 ng/mL), calcium intake of less than 800 mg/d vs more than 1200 mg/d was significantly associated with higher serum PTH (P = .04); and at a calcium intake of more than 1200 mg/d, there was a significant difference between the lowest and highest vitamin D groups (P = .04). CONCLUSIONS As long as vitamin D status is ensured, calcium intake levels of more than 800 mg/d may be unnecessary for maintaining calcium metabolism. Vitamin D supplements are necessary for adequate vitamin D status in northern climates.

Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes.

Recent evidence suggests that vitamin D intakes above current recommendations may be associated with better health outcomes. However, optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] have not been defined. This review summarizes evidence from studies that evaluated thresholds for serum 25(OH)D concentrations in relation to bone mineral density (BMD), lower-extremity function, dental health, and risk of falls, fractures, and colorectal cancer. For all endpoints, the most advantageous serum concentrations of 25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are between 90 and 100 nmol/L (36-40 ng/mL). In most persons, these concentrations could not be reached with the currently recommended intakes of 200 and 600 IU vitamin D/d for younger and older adults, respectively. A comparison of vitamin D intakes with achieved serum concentrations of 25(OH)D for the purpose of estimating optimal intakes led us to suggest that, for bone health in younger adults and all studied outcomes in older adults, an increase in the currently recommended intake of vitamin D is warranted. An intake for all adults of > or =1000 IU (25 microg) [DOSAGE ERROR CORRECTED] vitamin D (cholecalciferol)/d is needed to bring vitamin D concentrations in no less than 50% of the population up to 75 nmol/L. The implications of higher doses for the entire adult population should be addressed in future studies.

Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D.

BACKGROUND Calcium absorption is generally considered to be impaired under conditions of vitamin D deficiency, but the vitamin D status that fully normalizes absorption is not known for humans. OBJECTIVE To quantify calcium absorption at two levels of vitamin D repletion, using pharmacokinetic methods and commercially marketed calcium supplements. DESIGN Two experiments performed in the spring of the year, one year apart. In the first, in which participants were pretreated with 25-hydroxyvitamin D (25OHD), mean serum 25OHD concentration was 86.5 nmol/L; and in the other, with no pretreatment, mean serum concentration was 50.2 nmol/L. Participants received 500 mg oral calcium loads as a part of a standard low calcium breakfast. A low calcium lunch was provided at mid-day. Blood was obtained fasting and at frequent intervals for 10 to 12 hours thereafter. METHODS Relative calcium absorption at the two 25OHD concentrations was estimated from the area under the curve (AUC) for the load-induced increment in serum total calcium. RESULTS AUC(9) (+/- SEM), was 3.63 mg hr/dL +/- 0.234 in participants pretreated with 25OHD and 2.20 +/- 0.240 in those not pretreated (P < 0.001). In brief, absorption was 65% higher at serum 25OHD levels averaging 86.5 nmol/L than at levels averaging 50 nmol/L (both values within the nominal reference range for this analyte). CONCLUSIONS Despite the fact that the mean serum 25OHD level in the experiment without supplementation was within the current reference ranges, calcium absorptive performance at 50 nmol/L was significantly reduced relative to that at a mean 25OHD level of 86 nmol/L. Thus, individuals with serum 25-hydroxyvitamin D levels at the low end of the current reference ranges may not be getting the full benefit from their calcium intake. We conclude that the lower end of the current reference range is set too low.

Calcium and peak bone mass.

On the basis of previous epidemiological, clinical and experimental studies, it was demonstrated that adequate calcium intake during growth may influence peak bone mass/density, and may be instrumental in preventing subsequent postmenopausal and senile osteoporosis. Calcium intake during adolescence appears to affect skeletal calcium retention directly, and a calcium intake of up to 1600 mg d-1 may be required. Therefore, adolescent females at the time of puberty probably represent the optimal population for early prevention of osteoporosis with calcium. Young individuals must be in positive calcium balance to provide the calcium necessary for skeletal modelling and consolidation, but the degree of positive balance required to achieve peak bone mass and density is unknown. To assess calcium requirements in young individuals, and also to evaluate the determinants of calcium metabolism during the period of acquisition of peak bone mass, 487 calcium balances from previously published reports have been collected and analysed according to developmental phase and calcium intake. The results of this analysis showed that calcium intake and skeletal modelling/turnover are the most important determinants of calcium balance during growth. The highest requirements for calcium are during infancy and adolescence, and then during childhood and young adulthood. Infants (adequate vitamin D supply) and adolescents have higher calcium absorption than children and young adults to meet their high calcium requirements. Calcium absorption during the periods of rapid bone modelling/turnover is probably mediated by Nicolaysen's endogenous factor. Urinary calcium increases with age, and reaches a maximum by the end of puberty. The results also show that calcium intake has little effect on urinary calcium excretion during the period of most rapid skeletal formation: a weak correlation is present in children and young adults. On the basis of the above studies it was suggested that the RDA for calcium should be higher than currently established for children, adolescents, and young adults, in order to ensure a level of skeletal retention of calcium sufficient for maximal peak bone mass. In addition to nutrition, heredity (both parents) and endocrine factors (sexual development) appear to have profound effects on peak bone mass formation. Most of the skeletal mass will be accumulated by late adolescence, indicating early timing of peak bone mass.

Vitamin D status: measurement, interpretation, and clinical application.

Vitamin D, the sunshine vitamin, is now recognized not only for its importance in promoting bone health in children and adults but also for other health benefits, including reducing the risk of chronic diseases such as autoimmune diseases, common cancer, and cardiovascular disease. Vitamin D made in the skin or ingested in the diet is biologically inert and requires 2 successive hydroxylations first in the liver on carbon 25 to form 25-hydroxyvitamin D [25(OH)D], and then in the kidney for a hydroxylation on carbon 1 to form the biologically active form of vitamin D, 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. With the identification of 25(OH)D and 1,25(OH)(2)D, methods were developed to measure these metabolites in the circulation. Serum 25(OH)D is the barometer for vitamin D status. Serum 1,25(OH)(2)D provides no information about vitamin D status and is often normal or even increased as the result of secondary hyperparathyroidism associated with vitamin D deficiency. Most experts agree that 25(OH)D of <20 ng/mL is considered to be vitamin D deficiency, whereas a 25(OH)D of 21-29 ng/mL is considered to be insufficient. The goal should be to maintain both children and adults at a level >30 ng/mL to take full advantage of all the health benefits that vitamin D provides.

Increased growth after long-term oral 1alpha,25-vitamin D3 in childhood renal osteodystrophy.

We evaluated oral 1,25-vitamin D3 for as long as 26 months in six prepubescent children with renal osteodystrophy previously treated with vitamin D2. Therapy was given at 14 to 41 ng per kilogram per day to correct hypocalcemia and reverse bone disease. Serum levels of 1,25-vitamin D3 were initially reduced at 15 +/- 5 pg per milliliter (mean +/- S.E.M.) and after treatment rose to 54 +/- 13. Serum calcium rose from 7.5 +/- 1.6 mg per deciliter (mean +/- S.D.) to 9.8 +/- 0.6 after one month (P less than 0.02). Alkaline phosphatase activity fell from 536 +/- 298 to 208 +/- 91 IU per liter after 12 months (P less than 0.05). Serum immunoreactive parathyroid levels fell from 900 +/- 562 microliter eq per milliliter 411 +/- 377. Healing of rickets and subperiosteal erosions was found. Remineralization of bone was demonstrated by the photon absorption technic. In four patients growth velocity, evaluated for 12 months before and after therapy, increased from 2.6 +/- 0.8 to 8.0 +/- 3.2 cm per year. Growth velocity per year increased from less than third percentile in each to the 10th to 97th percentile after therapy. Height increment ranged from 27 to 113 per cent of that expected for change in chronologic age and 40 to 114 per cent expected for change in bone age after therapy. This trial demonstrates that oral 1,25-vitamin D3 can reverse renal bone disease and increase growth in uremic children.

Dosimetry and risk estimates of radioiodine therapy for large, multinodular goiters.

UNLABELLED In patients with a large, multinodular goiter (> 100 g), radiation absorbed doses in the thyroid, surrounding tissues and remainder of the body were estimated after therapeutic administration of 131I(3.7 MBq or 100 microCi/g of thyroid tissue retained at 24 hr). METHODS Thermoluminescent dosimeter (TLD) measurements were performed on 23 patients (12 euthyroid and 1I hyperthyroid; thyroid weight 222 +/- 72 g; 2.1 +/- 0.9 GBq 131I) on the skin over the thyroid, over the submandibular gland and over the parotid gland. Thyroid radioactivity measurements were done daily in 6 euthyroid and 6 hyperthyroid patients (thyroid weight 204 +/- 69 g; 1.9 +/- 0.9 GBq 131I). An iodine biokinetic model and the MIRD methodology were used to estimate absorbed doses in organs. Cancer risks were calculated using ICRP Publication 60. RESULTS Cumulated absorbed doses on the skin (TLD measurements) were 4.2 +/- 1.4 Gy (thyroid), 1.2 +/- 0.6 Gy (submandibular) and 0.4 +/- 0.2 Gy (parotid). All these values were significantly correlated with the amount of radioiodine retained in the thyroid at 24 hr (euthyroid versus hyperthyroid not significant). Absorbed doses in the thyroid of 94 +/- 25 Gy for euthyroid and 93 +/- 17 Gy for hyperthyroid patients were calculated (thyroid radioactivity measurements). Extrathyroidal absorbed doses (means of 12 patients) were 0.88 Gy in the urinary bladder, 0.57 Gy in the small intestine, 0.38 Gy in the stomach, and ranged from 0.05 to 0.30 Gy in other organs (euthyroid versus hyperthyroid not significant). A 1.6% life-time risk of development of cancer outside the thyroid gland was calculated. When applied to people of 65 yr and older the estimated risk is approximately 0.5%. CONCLUSION These data may help in choosing the treatment regimen for individual patients with a large, multinodular goiter, who have to be treated for hyperthyroidism or compressive problems. In younger patients, surgery may be preferred. However, for elderly patients and patients with cardiopulmonary disease, the advantages of noninvasive radioiodine treatment will outweight the life-time risk of this mode of therapy.

Effects of risedronate treatment on vertebral and nonvertebral fractures in women with postmenopausal osteoporosis: a randomized controlled trial. Vertebral Efficacy With Risedronate Therapy (VERT) Study Group.

CONTEXT Risedronate, a potent bisphosphonate, has been shown to be effective in the treatment of Paget disease of bone and other metabolic bone diseases but, to our knowledge, it has not been evaluated in the treatment of established postmenopausal osteoporosis. OBJECTIVE To test the efficacy and safety of daily treatment with risedronate to reduce the risk of vertebral and other fractures in postmenopausal women with established osteoporosis. DESIGN, SETTING, AND PARTICIPANTS Randomized, double-blind, placebo-controlled trial of 2458 ambulatory postmenopausal women younger than 85 years with at least 1 vertebral fracture at baseline who were enrolled at 1 of 110 centers in North America conducted between December 1993 and January 1998. INTERVENTIONS Subjects were randomly assigned to receive oral treatment for 3 years with risedronate (2.5 or 5 mg/d) or placebo. All subjects received calcium, 1000 mg/d. Vitamin D (cholecalciferol, up to 500 IU/d) was provided if baseline levels of 25-hydroxyvitamin D were low. MAIN OUTCOME MEASURES Incidence of new vertebral fractures as detected by quantitative and semiquantitative assessments of radiographs; incidence of radiographically confirmed nonvertebral fractures and change from baseline in bone mineral density as determined by dual x-ray absorptiometry. RESULTS The 2.5 mg/d of risedronate arm was discontinued after 1 year; in the placebo and 5 mg/d of risedronate arms, 450 and 489 subjects, respectively, completed all 3 years of the trial. Treatment with 5 mg/d of risedronate, compared with placebo, decreased the cumulative incidence of new vertebral fractures by 41 % (95% confidence interval [CI], 18%-58%) over 3 years (11.3 % vs 16.3%; P= .003). A fracture reduction of 65% (95% CI, 38%-81 %) was observed after the first year (2.4% vs 6.4%; P<.001). The cumulative incidence of nonvertebral fractures over 3 years was reduced by 39% (95% CI, 6%-61 %) (5.2 % vs 8.4%; P = .02). Bone mineral density increased significantly compared with placebo at the lumbar spine (5.4% vs 1.1 %), femoral neck (1.6% vs -1.2%), femoral trochanter (3.3% vs -0.7%), and midshaft of the radius (0.2% vs -1.4%). Bone formed during risedronate treatment was histologically normal. The overall safety profile of risedronate, including gastrointestinal safety, was similar to that of placebo. CONCLUSIONS These data suggest that risedronate therapy is effective and well tolerated in the treatment of women with established postmenopausal osteoporosis.

Prolonged effect of calcium supplementation on risk of colorectal adenomas in a randomized trial.

BACKGROUND Calcium supplementation has been shown to decrease the risk of recurrence of colorectal adenomas in randomized trials. However, the duration of this protective effect after cessation of active supplementation is not known. METHODS In the Calcium Polyp Prevention Study, 930 subjects with a previous colorectal adenoma were randomly assigned from November 1988 through April 1992 to receive placebo or 1200 mg of elemental calcium daily for 4 years. The Calcium Follow-up Study was an observational phase of the trial that tracked adenoma occurrence for an average of 7 years after the end of randomized treatment and gathered information regarding the use of medications, vitamins, and supplements during that time. We obtained follow-up information for 822 subjects, 597 of whom underwent at least one colonoscopy after the end of study treatment and are included in this analysis. Generalized linear models were used to compute relative risks (RRs) and 95% confidence intervals (CIs) for the effect of randomized calcium treatment on risk of adenoma recurrence during the first 5 years after study treatment ended and during the subsequent 5 years. Statistical tests were two-sided. RESULTS During the first 5 years after randomized treatment ended, subjects in the calcium group still had a substantially and statistically significantly lower risk of any adenoma than those in the placebo group (31.5% versus 43.2%; adjusted RR = 0.63, 95% CI = 0.46 to 0.87, P = .005) and a smaller and not statistically significant reduction in risk of advanced adenomas (adjusted RR = 0.85, 95% CI = 0.43 to 1.69, P = .65). However, the randomized treatment was not associated with the risk of any type of polyp during the next 5 years. The findings were broadly similar when the analysis was restricted to subjects who did not report use of any calcium supplements after the treatment phase of the trial ended. CONCLUSION The protective effect of calcium supplementation on risk of colorectal adenoma recurrence extends up to 5 years after cessation of active treatment, even in the absence of continued supplementation.

Global vitamin D levels in relation to age, gender, skin pigmentation and latitude: an ecologic meta-regression analysis

We performed a meta-analysis of cross-sectional studies on serum 25(OH)D status globally. Serum 25(OH)D levels on average were 54 nmol/l, were higher in women than men, and higher in Caucasians than in non-Caucasians. There was no trend in serum 25(OH)D level with latitude. Vitamin D deficiency was widespread. We studied vitamin D status (expressed as serum 25-hydroxy-vitamin D [25(OH)D]) in native subjects worldwide. Meta-analysis and meta-regression of studies reporting on 25(OH)D in healthy subjects retrieved from Pubmed, Embase and Web of Science using the terms “serum”, “25-hydroxy-vitamin D”, “cholecalciferol”, and “human”. A total of 394 studies were included. The mean 25(OH)D level was 54 nmol/l (95% CI: 52–57 nmol/l). Women had borderline significantly higher 25(OH)D levels than men, and Caucasians had higher levels than non-Caucasians. 25(OH)D levels were higher in subjects aged >15 years than in younger subjects. Unadjusted there was no significant decrease in 25(OH)D with latitude (slope of curve −0.03 ± 0.12 nmol/l per degree latitude north or south of equator, p = 0.8). There was a significant decline with latitude for Caucasians (−0.69 ± 0.30 nmol/l per degree, p = 0.02), but not for non-Caucasians (0.03 ± 0.39 nmol/l per degree, p = 0.14). After adjustment for age, gender, and ethnicity, no overall correlation was present between 25(OH)D and latitude (−0.29 ± 0.24 nmol/l per degree, p = 0.23). There was no overall influence of latitude on 25(OH)D. However, in separate analyses 25(OH)D decreased with latitude in Caucasians but not in non-Caucasians. A widespread global vitamin D insufficiency was present compared with proposed threshold levels.

Estimation of the dietary requirement for vitamin D in healthy adults.

BACKGROUND Knowledge gaps have contributed to considerable variation among international dietary recommendations for vitamin D.   OBJECTIVE We aimed to establish the distribution of dietary vitamin D required to maintain serum 25-hydroxyvitamin D [25(OH)D] concentrations above several proposed cutoffs (ie, 25, 37.5, 50, and 80 nmol/L) during wintertime after adjustment for the effect of summer sunshine exposure and diet. DESIGN A randomized, placebo-controlled, double-blind 22-wk intervention study was conducted in men and women aged 20-40 y (n = 238) by using different supplemental doses (0, 5, 10, and 15 microg/d) of vitamin D(3) throughout the winter. Serum 25(OH)D concentrations were measured by using enzyme-linked immunoassay at baseline (October 2006) and endpoint (March 2007). RESULTS There were clear dose-related increments (P < 0.0001) in serum 25(OH)D with increasing supplemental vitamin D(3). The slope of the relation between vitamin D intake and serum 25(OH)D was 1.96 nmol x L(-1) x microg(-1) intake. The vitamin D intake that maintained serum 25(OH)D concentrations of >25 nmol/L in 97.5% of the sample was 8.7 microg/d. This intake ranged from 7.2 microg/d in those who enjoyed sunshine exposure, 8.8 microg/d in those who sometimes had sun exposure, and 12.3 microg/d in those who avoided sunshine. Vitamin D intakes required to maintain serum 25(OH)D concentrations of >37.5, >50, and >80 nmol/L in 97.5% of the sample were 19.9, 28.0, and 41.1 microg/d, respectively. CONCLUSION The range of vitamin D intakes required to ensure maintenance of wintertime vitamin D status [as defined by incremental cutoffs of serum 25(OH)D] in the vast majority (>97.5%) of 20-40-y-old adults, considering a variety of sun exposure preferences, is between 7.2 and 41.1 microg/d.

Folate and vitamin B6 from diet and supplements in relation to risk of coronary heart disease among women.

CONTEXT Hyperhomocysteinemia is caused by genetic and lifestyle influences, including low intakes of folate and vitamin B6. However, prospective data relating intake of these vitamins to risk of coronary heart disease (CHD) are not available. OBJECTIVE To examine intakes of folate and vitamin B6 in relation to the incidence of nonfatal myocardial infarction (MI) and fatal CHD. DESIGN Prospective cohort study. SETTING AND PATIENTS In 1980, a total of 80082 women from the Nurses' Health Study with no previous history of cardiovascular disease, cancer, hypercholesterolemia, or diabetes completed a detailed food frequency questionnaire from which we derived usual intake of folate and vitamin B6. MAIN OUTCOME MEASURE Nonfatal MI and fatal CHD confirmed by World Health Organization criteria. RESULTS During 14 years of follow-up, we documented 658 incident cases of nonfatal MI and 281 cases of fatal CHD. After controlling for cardiovascular risk factors, including smoking and hypertension and intake of alcohol, fiber, vitamin E, and saturated, polyunsaturated, and trans fat, the relative risks (RRs) of CHD between extreme quintiles were 0.69 (95% confidence interval [CI], 0.55-0.87) for folate (median intake, 696 microg/d vs 158 microg/d) and 0.67 (95% CI, 0.53-0.85) for vitamin B6 (median intake, 4.6 mg/d vs 1.1 mg/d). Controlling for the same variables, the RR was 0.55 (95% CI, 0.41-0.74) among women in the highest quintile of both folate and vitamin B6 intake compared with the opposite extreme. Risk of CHD was reduced among women who regularly used multiple vitamins (RR=0.76; 95% CI, 0.65-0.90), the major source of folate and vitamin B6, and after excluding multiple vitamin users, among those with higher dietary intakes of folate and vitamin B6. In a subgroup analysis, compared with nondrinkers, the inverse association between a high-folate diet and CHD was strongest among women who consumed up to 1 alcoholic beverage per day (RR =0.69; 95% CI, 0.49-0.97) or more than 1 drink per day (RR=0.27; 95% CI, 0.13-0.58). CONCLUSION These results suggest that intake of folate and vitamin B6 above the current recommended dietary allowance may be important in the primary prevention of CHD among women.

Diminished linear growth during intermittent calcitriol therapy in children undergoing CCPD.

Daily calcitriol therapy has been reported to improve linear growth in children with renal bone disease, and 1,25-dihydroxyvitamin D is a key regultor of chondrocyte proliferation and differentiation. Whereas large intermittent doses of calcitriol can lower serum parathyroid hormone (PTH) levels and reverse the skeletal changes of secondary hyperparathyroidism, the impact of intermittent calcitriol therapy on linear growth in children is not known. Thus, we studied 16 pre-pubertal patients with bone biopsy-proven secondary hyperparathyroidism who completed a 12-month prospective clinical trial of intermittent calcitriol therapy. Biochemical results and growth data obtained during intermittent calcitriol therapy were compared to values determined during the preceding 12 months of daily calcitriol therapy in each study subject; changes in bone histology were assessed after one year of intermittent calcitriol therapy. Z-scores for height did not change during 12 months of daily calcitriol therapy. Although the skeletal lesions of secondary hyperparathyroidism improved in most patients, Z-scores for height decreased from -1.8 +/- 0.32 to -2.0 +/- 0.33, P < 0.01, during intermittent calcitriol therapy. The largest reductions were seen in patients who developed adynamic bone lesions after 12 months of treatment. Delta Z-scores for height correlated with serum PTH, r = 0.71, P < 0.01, and alkaline phosphatase levels, r = 0.67, P < 0.01, during intermittent calcitriol therapy but not during daily calcitriol therapy. The data suggest that high dose intermittent calcitriol therapy adversely affects linear growth, particularly in patients with the adynamic lesion. The higher doses of calcitriol or the intermittent schedule of calcitriol administration may directly inhibit chondrocyte activity within growth plate cartilage of children with end-stage renal disease.

Radioiodine treatment of multinodular non-toxic goitre.

OBJECTIVE To investigate the long term effect of radioactive iodine on thyroid function and size in patients with non-toxic multinodular goitre. DESIGN Consecutive patients with multinodular non-toxic goitre selected for radioactive iodine treatment and followed for a minimum of 12 months (median 48 months) after an intended dose of 3.7 MBq/g thyroid tissue corrected to a 100% uptake of iodine-131 in 24 hours. PATIENTS 69 patients with a growing multinodular non-toxic goitre causing local compression symptoms or cosmetic inconveniences. The treatment was chosen because of a high operative risk, previous thyroidectomy, or refusal to be operated on. MAIN OUTCOME MEASUREMENTS Standard thyroid function variables and ultrasonically determined thyroid volume before treatment as well as 1, 2, 3, 6, and 12 months after treatment and then once a year. RESULTS 56 patients were treated with a single dose of 131I, 12 with two doses, and one with four doses. In 45 patients treated with one dose and remaining euthyroid the median thyroid volume was reduced from 73 (interquartile range 50-106) ml to 29 (23-48) ml at 24 months in the 39 patients in whom this was measured during follow up. The median reduction was 40 (22-48) ml (60% reduction, p < 0.0001), half of which occurred within three months. Patients treated with two doses as well as those developing hypothyroidism and hyperthyroidism had a significant reduction in thyroid volume. Eleven patients developed hypothyroidism (cumulative five year risk 22%, 95% confidence interval 4.8% to 38.4%). Side effects were few: three cases of hyperthyroidism and two cases of radiation thyroiditis. Only one patient was dissatisfied with the result; she was referred for operation six months after treatment. CONCLUSIONS A substantial reduction in thyroid volume accompanied by a low incidence of hypothyroidism and few side effects makes the use of radioactive iodine an attractive alternative to surgery in selected cases of non-toxic multinodular goitre.

Mammographic density, plasma vitamin D levels and risk of breast cancer in postmenopausal women.

Mammographic density is a strong risk factor for breast cancer, but the underlying biology for this association is unknown. Studies suggest that vitamin D may reduce breast cancer risk and dietary vitamin D intake has been associated with reduced breast density. We conducted a case-control study nested within the Nurses' Health Study cohort consisting of 463 and 497 postmenopausal cases and controls, respectively. We examined the association between mammographic density and plasma levels of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. We assessed whether plasma vitamin D metabolites modify the association between breast density and breast cancer. Percent mammographic density was measured from digitized film mammograms. Generalized linear models were used to determine mean percent breast density per quartile of vitamin D metabolite. Logistic regression models were used to calculate relative risks and confidence intervals. All models were adjusted for matching variables and potential confounders. We found no cross-sectional association between circulating levels of 25(OH)D or 1,25(OH)(2)D with mammographic density. Women in the highest tertile of mammographic density and lowest tertile of plasma 25(OH)D had 4 times greater risk of breast cancer than women with the lowest mammographic density and highest plasma 25(OH)D levels (RR = 3.8; 95% CI: 2.0-7.3). The overall interaction between mammographic density and plasma 25(OH)D was nonsignificant (p-het = 0.20). These results indicate that the association between mammographic density and breast cancer is independent of plasma vitamin D metabolites in postmenopausal women. Further research examining vitamin D, mammographic density and breast cancer risk is warranted.

Genetic and environmental determinants of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels in Hispanic and African Americans.

CONTEXT Vitamin D deficiency is associated with many adverse health outcomes, yet little is known about the genetic epidemiology of vitamin D or its metabolites. OBJECTIVE Our objective was to examine the relationship among three vitamin D-related genes and levels of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] in Hispanics (HAs) and African Americans (AAs). DESIGN AND SETTING The cross-sectional Insulin Resistance Atherosclerosis Family Study recruited and examined subjects in: Los Angeles, California (AAs; 513 individuals from 42 families); San Luis Valley (SLV), Colorado (HAs; 513 individuals from 30 families); and San Antonio (SA), Texas (HAs; 504 individuals from 58 families). MAIN OUTCOME MEASURES Plasma levels of 25(OH)D and 1,25(OH)2D were measured. RESULTS Levels of 25(OH)D were highest in SLV-HAs [18.3 +/- 7.7 ng/ml (45.7 +/- 19.2 nmol/liter)], lower in SA-HAs [14.6 +/- 6.4 ng/ml (36.4 +/- 16.0 nmol/liter)], and lowest in AAs [11.0 +/- 5.4 ng/ml (27.5 +/- 13.5 nmol/liter)]. Levels of 1,25(OH)2D were similar in AAs [43.5 +/- 13.9 pg/ml (113.1 +/- 36.1 pmol/liter)] and SLV-HAs [43.2 +/- 13.3 pg/ml (112.3 +/- 34.6 pmol/liter)], but higher in SA-HAs [48.6 +/- 17.0 pg/ml (126.4 +/- 44.2 pmol/liter)]. After adjusting for gender and age within the site, two single nucleotide polymorphisms (SNPs) in the vitamin D binding protein gene (DBP), rs4588 and rs7041, were associated with 25(OH)D, and one SNP in the DBP, rs4588, was associated with 1,25(OH)2D at all three study centers. CONCLUSIONS SNPs in the DBP are associated with levels of 25(OH)D and 1,25(OH)2D in HA and AA participants in the Insulin Resistance Atherosclerosis Family Study.

Genetic variants and non-genetic factors predict circulating vitamin D levels in Hispanic and non-Hispanic White women: the Breast Cancer Health Disparities Study.

Genome-wide association studies (GWAS) have identified common polymorphisms in or near GC, CYP2R1, CYP24A1, and NADSYN1/DHCR7 genes to be associated with circulating levels of 25-hydroxyvitamin D [25(OH)D] in European populations. To replicate these GWAS findings, we examined six selected polymorphisms from these regions and their relation with circulating 25(OH)D levels in 1,605 Hispanic women (629 U.S. Hispanics and 976 Mexicans) and 354 non-Hispanic White (NHW) women. We also assessed the potential interactions between these variants and known non-genetic predictors of 25(OH)D levels, including body mass index (BMI), sunlight exposure and vitamin D intake from diet and supplements. The minor alleles of the two GC polymorphisms (rs7041 and rs2282679) were significantly associated with lower 25(OH)D levels in both Hispanic and NHW women. The CYP2R1 polymorphism, rs2060793, also was significantly associated with 25(OH)D levels in both groups. We found no significant associations for the polymorphisms in the CYP24A1. In Hispanic controls, 25(OH)D levels were significantly associated with the rs12785878T and rs1790349G haplotype in the NADSYN1/DHCR7 region. Significant interactions between GC rs2282679 and BMI and between rs12785878 and time spent in outdoor activities were observed. These results provide further support for the contribution of common genetic variants to individual variability in circulating 25(OH)D levels. The observed interactions between SNPs and non-genetic factors warrant confirmation.

Plasma vitamin D metabolites and risk of colorectal cancer in women.

OBJECTIVE Experimental evidence suggests that 1,25-dihydroxyvitamin D and its precursor, 25-hydroxyvitamin D [25(OH)D], may aid in the prevention of colorectal cancer. We therefore examined risk in relation to plasma concentrations of these vitamin D metabolites. METHODS In a nested case-control study among women in the Nurses' Health Study, we identified 193 colorectal cancer cases, ages 46 to 78 years, diagnosed up to 11 years after blood collection. Two controls were matched per case on year of birth and month of blood draw. Odds ratios (OR) for risk of colorectal cancer were calculated using conditional logistic regression adjusted for body mass index, physical activity, smoking, family history, use of hormone replacement therapy, aspirin use, and dietary intakes. RESULTS We found a significant inverse linear association between plasma 25(OH)D and risk of colorectal cancer (P = 0.02). Among women in the highest quintile, the OR (95% confidence interval) was 0.53 (0.27-1.04). This inverse association remained strong when limited to women > or =60 years at blood collection (P = 0.006) but was not apparent among the younger women (P = 0.70). Benefit from higher 25(OH)D concentrations was observed for cancers at the distal colon and rectum (P = 0.02) but was not evident for those at the proximal colon (P = 0.81). In contrast to 25(OH)D, we did not observe an association between 1,25-dihydroxyvitamin D and colorectal cancer, although risk was elevated among the women in the highest quintile if they were also in the lower half of the 25(OH)D distribution (OR, 2.52; 95% confidence interval, 1.04-6.11). CONCLUSION From these results and supporting evidence from previous studies, we conclude that higher plasma levels of 25(OH)D are associated with a lower risk of colorectal cancer in older women, particularly for cancers at the distal colon and rectum.

Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol.

BACKGROUND The cholecalciferol inputs required to achieve or maintain any given serum 25-hydroxycholecalciferol concentration are not known, particularly within ranges comparable to the probable physiologic supply of the vitamin. OBJECTIVES The objectives were to establish the quantitative relation between steady state cholecalciferol input and the resulting serum 25-hydroxycholecalciferol concentration and to estimate the proportion of the daily requirement during winter that is met by cholecalciferol reserves in body tissue stores. DESIGN Cholecalciferol was administered daily in controlled oral doses labeled at 0, 25, 125, and 250 micro g cholecalciferol for approximately 20 wk during the winter to 67 men living in Omaha (41.2 degrees N latitude). The time course of serum 25-hydroxycholecalciferol concentration was measured at intervals over the course of treatment. RESULTS From a mean baseline value of 70.3 nmol/L, equilibrium concentrations of serum 25-hydroxycholecalciferol changed during the winter months in direct proportion to the dose, with a slope of approximately 0.70 nmol/L for each additional 1 micro g cholecalciferol input. The calculated oral input required to sustain the serum 25-hydroxycholecalciferol concentration present before the study (ie, in the autumn) was 12.5 micro g (500 IU)/d, whereas the total amount from all sources (supplement, food, tissue stores) needed to sustain the starting 25-hydroxycholecalciferol concentration was estimated at approximately 96 micro g (approximately 3800 IU)/d. By difference, the tissue stores provided approximately 78-82 micro g/d. CONCLUSIONS Healthy men seem to use 3000-5000 IU cholecalciferol/d, apparently meeting > 80% of their winter cholecalciferol need with cutaneously synthesized accumulations from solar sources during the preceding summer months. Current recommended vitamin D inputs are inadequate to maintain serum 25-hydroxycholecalciferol concentration in the absence of substantial cutaneous production of vitamin D.

Vitamin D insufficiency and the blunted PTH response in established osteoporosis: the role of magnesium deficiency

Vitamin D insufficiency is common, however within individuals, not all manifest the biochemical effects of PTH excess. This further extends to patients with established osteoporosis. The mechanism underlying the blunted PTH response is unclear but may be related to magnesium (Mg) deficiency. The aims of this study were to compare in patients with established osteoporosis and differing degrees of vitamin D and PTH status : (1) the presence of Mg deficiency using the standard Mg loading test (2) evaluate the effects of Mg loading on the calcium-PTH endocrine axis (3) determine the effects of oral, short term Mg supplementation on the calcium-PTH endocrine axis and bone turnover. 30 patients (10 women in 3 groups) were evaluated prospectively measuring calcium, PTH, Mg retention (Mg loading test), dietary nutrient intake (calcium, vitamin D, Mg) and bone turnover markers (serum CTX & P1CP). Multivariate analysis controlling for potential confounding baseline variable was undertaken for the measured outcomes. All subjects, within the low vitamin D and low PTH group following the magnesium loading test had evidence of Mg depletion [mean(SD) retention 70.3%(12.5)] and showed an increase in calcium 0.06(0.01) mmol/l [95% CI 0.03, 0.09, p=0.007], together with a rise in PTH 13.3 ng/l (4.5) [95% CI 3.2, 23.4, p=0.016] compared to baseline. Following oral supplementation bone turnover increased: CTX 0.16 (0.06) mcg/l [95%CI 0.01, 0.32 p=0.047]; P1CP 13.1 (5.7) mcg/l [95% CI 0.29, 26.6 p=0.049]. In subjects with a low vitamin D and raised PTH mean retention was 55.9%(14.8) and in the vitamin replete group 36.1%(14.4), with little change in both acute markers of calcium homeostasis and bone turnover markers following both the loading test and oral supplementation. This study confirms that in patients with established osteoporosis, there is also a distinct group with a low vitamin D and a blunted PTH level and that Mg deficiency (as measured by the Mg loading test) is an important contributing factor.

Complementary foods for infant feeding in developing countries: their nutrient adequacy and improvement

Objective: To assess the energy and nutrient adequacy of a variety of complementary foods used in parts of Africa, India, Papua New Guinea, the Philippines and Thailand. Method: The energy, nutrient and anti-nutrient (dietary fibre and phytic acid) content (per 100 g as eaten, per 100 kcal, and per day) of twenty-three plant-based complementary foods consumed in developing countries was calculated from food composition values based on chemical analysis for the trace minerals, non-starch polysaccharide and phytic acid, and the literature. Results were compared with the estimated nutrient needs (per day; per 100 kcal) from complementary foods for infants 9–11 months, assuming a breast milk intake of average volume and composition and three complementary feedings per day, each of 250 g. Results: Complementary foods should provide approximately 25–50% of total daily requirements for protein, riboflavin and copper; 50–75% for thiamin, calcium and manganese; and 75–100% for phosphorus, zinc and iron. Most or all appear to meet the estimated daily nutrient needs (per day; per 100 kcal) from complementary foods for protein, thiamin and copper (per day), but not for calcium, iron, and in some cases zinc, even if moderate bioavailability for iron and zinc is assumed. Some of those based on rice are also inadequate in riboflavin (per day; per 100 kcal).Conclusions: Even if strategies to improve the bioavailability of iron and zinc are employed, they are probably insufficient to overcome the deficits in calcium, iron and zinc. Therefore, research on the feasibility of fortifying plant-based complementary foods in developing countries with calcium, iron and zinc is urgently required. Sponsorship: This study was supported by the Micronutrient Initiative through the Canadian International Development Agency.

Vitamin D and obesity: current perspectives and future directions.

In recent years, new functional roles of vitamin D beyond its traditional role in calcium homoeostasis and bone metabolism have emerged linking the fat-soluble vitamin to various non-communicable diseases. Vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25-30 nmol/l) and sub-optimal status (25(OH)D < 50-100 nmol/l) are increasingly associated with unfavourable metabolic phenotypes, including insulin resistance, type 2 diabetes and CVD; conditions also commonly linked with overweight and obesity. Early studies reported poor vitamin D status in the morbidly obese. More recently, it has been observed that a graded relationship between vitamin D status and BMI, or specifically adiposity, exists in the general population. A number of hypotheses have been proposed to explain the potential mechanisms whereby alterations in the vitamin D endocrine system occur in the obese state. Plausible explanations include sequestration in adipose tissue, volumetric dilution or negative feedback mechanisms from increased circulating 1,25-dihydroxyvitamin D3. Others hypothesise that heavier individuals may partake in less outdoor activity, may also cover-up and wear more clothing than leaner individuals, thus decreasing sun exposure and limiting endogenous production of cholecalciferol in the skin. Moreover, in some but not all studies, BMI and adiposity have been negatively associated with the change in vitamin D status following vitamin D supplementation. It therefore remains unclear if body size and/or adiposity should be taken into account when determining the dietary requirements for vitamin D. This review will evaluate the current evidence linking vitamin D status and supplementation to overweight and obesity, and discuss the implications for setting dietary requirements.

Parathyroid Hormone Directs Bone Marrow Mesenchymal Cell Fate.

Intermittent PTH administration builds bone mass and prevents fractures, but its mechanism of action is unclear. We genetically deleted the PTH/PTHrP receptor (PTH1R) in mesenchymal stem cells using Prx1Cre and found low bone formation, increased bone resorption, and high bone marrow adipose tissue (BMAT). Bone marrow adipocytes traced to Prx1 and expressed classic adipogenic markers and high receptor activator of nuclear factor kappa B ligand (Rankl) expression. RANKL levels were also elevated in bone marrow supernatant and serum, but undetectable in other adipose depots. By cell sorting, Pref1+RANKL+ marrow progenitors were twice as great in mutant versus control marrow. Intermittent PTH administration to control mice reduced BMAT significantly. A similar finding was noted in male osteoporotic patients. Thus, marrow adipocytes exhibit osteogenic and adipogenic characteristics, are uniquely responsive to PTH, and secrete RANKL. These studies reveal an important mechanism for PTH's therapeutic action through its ability to direct mesenchymal cell fate.

Vitamin D and prevention of colorectal cancer.

BACKGROUND Inadequate photosynthesis or oral intake of Vitamin D are associated with high incidence rates of colorectal cancer, but the dose-response relationship has not been adequately studied. METHODS Dose-response gradients from observational studies of Vitamin D intake and serum 25-hydroxyvitamin D were plotted as trend lines. The point on each linear trend line corresponding to an odds ratio of 0.50 provided the prediagnostic Vitamin D intake or 25-hydroxyvitamin D concentration associated with 50% lower risk compared to <100IU/day Vitamin D or <13ng/ml serum 25-hydroxyvitamin D. Medians of these values were determined. RESULTS Overall, individuals with >or=1000IU/day oral Vitamin D (p<0.0001) or >or=33ng/ml (82nmol/l) serum 25-hydroxyvitamin D (p<0.01) had 50% lower incidence of colorectal cancer compared to reference values. CONCLUSIONS Intake of 1000IU/day of Vitamin D, half the safe upper intake established by the National Academy of Sciences, was associated with 50% lower risk. Serum 25-hydroxyvitamin D of 33ng/ml, which is known to be safe, also was associated with 50% lower risk. Prompt public health action is needed to increase intake of Vitamin D(3) to 1000IU/day, and to raise 25-hydroxyvitamin D by encouraging a modest duration of sunlight exposure.

British Journal of Nutrition (2003), 89, 295–301 q The Authors 2003 DOI: 10.1079/BJN2002776 Plasma homocysteine concentration is decreased by dietary intervention*

High plasma total homocysteine (tHcy) concentration is reported to be a risk factor for vascular diseases. We investigated the extent to which serum folate and plasma tHcy respond to a high intake of natural folate from food. Thirty-seven healthy females volunteered t o participate in a crossover dietary intervention. The study included a baseline period and two 5-week diet periods (low- and high-folate diets) with a 3-week washout in between. The low-folate diet contained one serving of both vegetables and fruit/d, while during the high-folate diet the subjects ate at least seven servings of vegetables, berries, and citrus fruit/d. Serum and erythrocyte (RBC) folate, serum vitamin B (12), and plasma tHcy concentrations were measured at the base-line and at the end of each diet period. The mean concentrations of serum and RBC folate were 11.0 (SD 3.0) nmol/l and 412 (SD 120) nmol/l at the end of the low-folate diet and 78 (95 % CI 62, 94) % and 14 (95 % CI 8, 20) % higher in response to the high-folate diet (P< 0.001). The serum concentration of vitamin B12 remained unchanged during the intervention. The mean plasma tHcy concentration was 8.0 pmol/ at the end of the low-folate diet and decreased by 13 (95% CI 9, 18) % in response to the high-folate diet (P<0.001). In conclusion, a diet high in fresh berries, citrus fruit, and vegetables effectively increases serum and RBC folate and decreases plasma homocysteine.

Effect of women's nutrition before and during early pregnancy on maternal and infant outcomes: a systematic review.

Current understanding of biologic processes indicates that women's nutritional status before and during early pregnancy may play an important role in determining early developmental processes and ensuring successful pregnancy outcomes. We conducted a systematic review of the evidence for the impact of maternal nutrition before and during early pregnancy (<12 weeks gestation) on maternal, neonatal and child health outcomes and included 45 articles (nine intervention trials and 32 observational studies) that were identified through PubMed and EMBASE database searches and examining review articles. Intervention trials and observational studies show that periconceptional (<12 weeks gestation) folic acid supplementation significantly reduced the risk of neural tube defects. Observational studies suggest that preconceptional and periconceptional intake of vitamin and mineral supplements is associated with a reduced risk of delivering offspring who are low birthweight and/or small-for-gestational age (SGA) and preterm deliveries (PTD). Some studies report that indicators of maternal prepregnancy size, low stature, underweight and overweight are associated with increased risks of PTD and SGA. The available data indicate the importance of women's nutrition prior to and during the first trimester of pregnancy, but there is a need for well-designed prospective studies and controlled trials in developing country settings that examine relationships with low birthweight, SGA, PTD, stillbirth and maternal and neonatal mortality. The knowledge gaps that need to be addressed include the evaluation of periconceptional interventions such as food supplements, multivitamin-mineral supplements and/or specific micronutrients (iron, zinc, iodine, vitamin B-6 and B-12) as well as the relationship between measures of prepregnancy body size and composition and maternal, neonatal and child health outcomes.

Low serum vitamin D is associated with high risk of diabetes in Korean adults.

Vitamin D may play a role in glucose metabolism. A low vitamin D level has been associated with increased risk of diabetes mellitus, but the association has not been confirmed in Asians. Our objective was to examine the association of serum 25-hydroxyvitamin D [25(OH)D] levels with insulin resistance and diabetes mellitus in Korean adults based on a large population-based survey. Cross-sectional analyses were carried out on 5787 Korean adults (2453 men and 3334 women) who were 20 y or older and participated in the Fourth Korea NHANES conducted in 2008. Diabetes mellitus was defined as fasting plasma glucose ≥7 mmol/L or current use of oral hypoglycemic agents or insulin. Insulin resistance was estimated by homeostatic model assessment for insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI). Compared to individuals with a sufficient serum 25(OH)D concentration ≥75 nmol/L, the OR (95% CI) for diabetes mellitus were 1.73 (1.09-2.74), 1.30 (0.91-1.84), and 1.40 (0.99-1.98) for serum 25(OH)D concentrations <25, 25 to <50, and 50 to <75 nmol/L, respectively, after multiple adjustments (P-trend < 0.0001). Furthermore, the serum 25(OH)D level was inversely associated with HOMA-IR (β = -0.061; P = 0.001) and positively associated with QUICKI (β = 0.059; P = 0.001) in overweight or obese participants. In conclusion, a low serum vitamin D concentration is associated with a high risk of diabetes mellitus in Korean adults and the concentration is inversely associated with insulin resistance in those who are overweight or obese.

Relation between renal function within the normal range and central and peripheral arterial stiffness in hypertension.

Chronic kidney disease is accompanied by increased large-artery stiffness, but the relation between glomerular filtration rate within the reference range and central or peripheral arterial stiffness has been understudied. The link between renal function and arterial stiffness was assessed in 305 patients with never-treated essential hypertension (men: 58%; age: 48+/-11 years, blood pressure: 151/95+/-20/11 mm Hg), free from overt cardiovascular disease and with serum creatinine values <1.4 mg/dL (men) and <1.2 mg/dL (women), who underwent noninvasive aortic and upper-limb pulse wave velocity (PWV) determination. Aortic PWV was strongly related to age (r=0.55; P<0.001), whereas upper-limb PWV had a weaker nonlinear relation with age (beta=1.392; P<0.001 for age; beta=-1.312; P<0.001 for age squared) and a weak relation with aortic PWV (r=0.22; P<0.001). Glomerular filtration rate (GFR), estimated according to the Mayo clinic equation for healthy subjects, was inversely correlated with large-artery stiffness, as assessed by aortic PWV (r=-0.34; P<0.001), and with peripheral artery stiffness, as assessed by upper-limb PWV (r=-0.25; P<0.001). In a multivariate linear regression, aortic PWV was independently predicted by age (beta=0.48; P<0.001), mean arterial pressure (beta=0.14; P=0.013), and GFR (beta=-0.13, P=0.029). Upper-limb PWV was predicted by GFR (beta=-0.24; P<0.001) and mean arterial pressure (beta=0.20; P<0.001). We conclude that, in hypertensive patients with normal renal function, an inverse relationship exists between GFR and stiffness of both central elastic and peripheral muscular arteries. These relations are in part independent from the effect of several confounders, including age, sex, and blood pressure values.

Primary prevention of hypertension: clinical and public health advisory from The National High Blood Pressure Education Program.

The National High Blood Pressure Education Program Coordinating Committee published its first statement on the primary prevention of hypertension in 1993. This article updates the 1993 report, using new and further evidence from the scientific literature. Current recommendations for primary prevention of hypertension involve a population-based approach and an intensive targeted strategy focused on individuals at high risk for hypertension. These 2 strategies are complementary and emphasize 6 approaches with proven efficacy for prevention of hypertension: engage in moderate physical activity; maintain normal body weight; limit alcohol consumption; reduce sodium intake; maintain adequate intake of potassium; and consume a diet rich in fruits, vegetables, and low-fat dairy products and reduced in saturated and total fat. Applying these approaches to the general population as a component of public health and clinical practice can help prevent blood pressure from increasing and can help decrease elevated blood pressure levels for those with high normal blood pressure or hypertension.

Origin of nitrite and nitrate in nasal and exhaled breath condensate and relation to nitric oxide formation.

BACKGROUND Raised concentrations of nitrate and nitrite have been found in exhaled breath condensate (EBC) in airway disease, and it has been postulated that this reflects increased nitric oxide (NO) metabolism. However, the chemical and anatomical origin of nitrate and nitrite in the airways has not yet been sufficiently studied. METHODS The fraction of exhaled NO at an exhalation flow rate of 50 ml/s (FE(NO)) and nitrite and nitrate in EBC, nasal condensate, and saliva were measured in 17 tracheostomised and 15 non-tracheostomised subjects, all of whom were non-smokers without respiratory disease. Tracheal and oral samples were taken from the tracheostomised subjects and nasal (during velum closure) and oral samples from the non-tracheostomised subjects. Measurements were performed before and after sodium nitrate ingestion (10 mg/kg) and use of antibacterial mouthwash (chlorhexidine 0.2%). RESULTS In tracheostomised subjects oral FE(NO) increased by 90% (p<0.01) while tracheal FE(NO) was not affected 60 minutes after nitrate ingestion. Oral EBC nitrite levels were increased 23-fold at 60 minutes (p<0.001) whereas the nitrite levels in tracheal EBC showed only a minor increase (fourfold, p<0.05). Nitrate was increased the same amount in oral and tracheal EBC at 60 minutes (2.5-fold, p<0.05). In non-tracheostomised subjects oral FE(NO) and EBC nitrite increased after nitrate ingestion and after chlorhexidine mouthwash they approached baseline levels again (p<0.001). Nasal NO, nitrate, and nitrite were not affected by nitrate intake or mouthwash. At baseline, mouthwash with deionised water did not affect nitrite in oral EBC or saliva, whereas significant reductions were seen after antibacterial mouthwash (p<0.05 and p<0.001, respectively). CONCLUSIONS Besides the salivary glands, plasma nitrate is taken up by the lower airways but not the nasal airways. Nitrate levels in EBC are thus influenced by dietary intake. Nitrate is reduced to nitrite by bacterial activity which takes place primarily in the oropharyngeal tract of healthy subjects. Only oropharyngeal nitrite seems to contribute to exhaled NO in non-inflamed airways, and there is also a substantial contribution of nitrite from the oropharyngeal tract during standard collection of EBC.

Predictive value of bone resorption and formation markers in cancer patients with bone metastases receiving the bisphosphonate zoledronic acid.

PURPOSE Three large, randomized trials of patients with bone metastases recently demonstrated that zoledronic acid reduces the risk of skeletal-related events. These trials provide an opportunity for investigating the correlation between bone metabolism and clinical outcome during bisphosphonate therapy. PATIENTS AND METHODS Urinary measurements of N-telopeptide (Ntx) and serum bone alkaline phosphatase (BAP) were obtained in 1,824 bisphosphonate-treated patients-1,462 with zoledronic acid (breast, 490; prostate, 411; myeloma, 210; non-small-cell lung, 183; other, 168) and 362 with pamidronate (breast, 254; myeloma, 108). This exploratory cohort analysis grouped patients by baseline and most recent levels of Ntx as low (< 50 nmol/mmol creatinine), moderate (50 to 99 nmol/mmol creatinine), or high (> or = 100 nmol/mmol creatinine), and BAP as low (< 146 U/L) or high (> or = 146 U/L). The relative risks for negative clinical outcomes were estimated for each group using multiple-event and Cox regression models with time-varying covariates. RESULTS Patients with high and moderate Ntx levels had 2-fold increases in their risk of skeletal complications and disease progression compared with patients with low Ntx levels (P < .001 for all). High Ntx levels in each solid tumor category were associated with a 4- to 6-fold increased risk of death on study, and moderate Ntx levels a 2- to 4-fold increased risk compared with low Ntx levels (P < .001 for all). Bone alkaline phosphatase also showed some correlation with risk of negative clinical outcomes. CONCLUSION The bone resorption marker Ntx provides valuable prognostic information in patients with bone metastases receiving bisphosphonates.

Randomized trial of folic acid supplementation and serum homocysteine levels.

BACKGROUND Lowering serum homocysteine levels with folic acid is expected to reduce mortality from ischemic heart disease. Homocysteine reduction is known to be maximal at a folic acid dosage of 1 mg/d, but the effect of lower doses (relevant to food fortification) is unclear. METHODS We randomized 151 patients with ischemic heart disease to 1 of 5 dosages of folic acid (0.2, 0.4, 0.6, 0.8, and 1.0 mg/d) or placebo. Fasting blood samples for serum homocysteine and serum folate analysis were taken initially, after 3 months of supplementation, and 3 months after folic acid use was discontinued. RESULTS Median serum homocysteine level decreased with increasing folic acid dosage, to a maximum at 0.8 mg of folic acid per day, when the homocysteine reduction (placebo adjusted) was 2.7 micromol/L (23%), similar to the known effect of folic acid dosages of 1 mg/d and above. The higher a person's initial serum homocysteine level, the greater was the response to folic acid, but there were statistically significant reductions regardless of the initial level. Serum folate level increased approximately linearly (5.5 nmol/L for every 0.1 mg of folic acid). Within-person fluctuations over time in serum homocysteine levels, measured in the placebo group, were large compared with the effect of folic acid, indicating that monitoring of the reduction in an individual is impractical. CONCLUSIONS A dosage of folic acid of 0.8 mg/d appears necessary to achieve the maximum reduction in serum homocysteine level across the range of homocysteine levels in the population. Current US food fortification levels will achieve only a small proportion of the achievable homocysteine reduction.

Preventing coronary heart disease: B vitamins and homocysteine.

The list of preventable and reversible risk factors for atherosclerotic cardiovascular disease continues to grow. Cigarette smoking, high blood pressure, physical inactivity, elevated cholesterol, underlying lipoprotein abnormalities, lipoprotein(a), diabetes, overweight, male gender, and age are well-established risk factors. During the 1990s, there have been many reports associating elevated plasma homocysteine levels with arteriosclerotic cardiovascular disease and consistent evidence that dietary and supplemental folic acid can reduce homocysteine levels.1 2   The article by Robinson and colleagues3 in this issue of Circulation presents further evidence of the importance of homocysteine and suggestive evidence that plasma folate and plasma pyrixodal-l-phosphate (vitamin B6) are protective factors. Their study is part of the European Concerted Action Project,4 which examined 750 patients younger than age 60 with diagnoses within the previous 12 months of coronary, cerebrovascular, or peripheral vascular disease and 800 healthy control subjects. The patient groups were young (47 years for cases and 44 years for control subjects) and heterogeneous, with nonfatal clinical events or symptoms of arteriosclerotic cardiovascular disease supported by ECG, angiographic, or Doppler evidence; the study involved 19 centers in nine European countries. Men in the highest quintile for fasting total homocysteine (tHcy), compared with the remainder of the population, had an estimated relative risk of 2.2 (95% confidence interval [CI], 1.6 to 2.9), with a striking dose-response relationship and a more-than-multiplicative interaction with cigarette smoking and high blood pressure on vascular disease risk4 ; the corresponding estimated relative risk for coronary heart disease was similar (2.0; 95% CI 1.6 to 2.8). (tHcy is the sum of homocysteine and homocysteinyl moieties of oxidized disulfides, homocystine, and cysteine- homocysteine. ) Robinson and colleagues3 examined three B vitamins in detail to determine their effects on fasting and post–methionine-loading tHcy levels and any independent effects on cardiovascular disease …

Hemoperfusion-hemodialysis ineffective for paraquat removal in life-threatening poisoning?

We report on a patient treated with hemoperfusion-hemodialysis (HP-HD) for severe paraquat poisoning. This procedure was adopted since the combination of adsorption and dialysis may improve overall drug removal. On admission blood paraquat was 15.8 micrograms/ml. He received conventional treatment and combined HP-HD which started within 3 hours after ingestion of the chemical and lasted 5 hours. Blood samples were obtained during and after HP-HD. The samples during HP-HD were taken before the charcoal column, between the charcoal column and the artificial kidney and after the artificial kidney. Blood clearances of paraquat were 116 +/- 32 ml/min (n=6) for the charcoal column (HP), 90 +/- 54 ml/min (n=6) for the artificial kidney (HD) and 151 +/- 37 ml/min (n=6) for the combined systems (HP-HD). After HP-HD a limited rebound of blood paraquat level was seen. One day after admission renal and hepatic failure had developed, and the patient died after 5 days. Tissue paraquat levels (microgram/g wet tissue) were: skeletal muscle 9.4, pancreas 6.0, prostate 5.6, thyroid 4.2, lungs 4.0, bone marrow 4.0, kidney 3.1, spleen 2.9, adrenal 2.9, heart 2.8, liver 2.3, stomach and testis below 1.0. Measurements of blood levels demonstrated the efficient clearances of paraquat with HP-HD from the central (plasma) compartment. However, the present results confirmed those previously reported which suggest that the efficiency of short HP-HD in treating severe paraquat poisoning is questionable since paraquat levels in the peripheral (tissue) compartment remain elevated.

Molecular Mechanisms of Vitamin D Action

The hormonal metabolite of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D), initiates biological responses via binding to the vitamin D receptor (VDR). When occupied by 1,25D, VDR interacts with the retinoid X receptor (RXR) to form a heterodimer that binds to vitamin D responsive elements in the region of genes directly controlled by 1,25D. By recruiting complexes of either coactivators or corepressors, ligand-activated VDR-RXR modulates the transcription of genes encoding proteins that promulgate the traditional functions of vitamin D, including signaling intestinal calcium and phosphate absorption to effect skeletal and calcium homeostasis. Thus, vitamin D action in a particular cell depends upon the metabolic production or delivery of sufficient concentrations of the 1,25D ligand, expression of adequate VDR and RXR coreceptor proteins, and cell-specific programming of transcriptional responses to regulate select genes that encode proteins that function in mediating the effects of vitamin D. For example, 1,25D induces RANKL, SPP1 (osteopontin), and BGP (osteocalcin) to govern bone mineral remodeling; TRPV6, CaBP9k, and claudin 2 to promote intestinal calcium absorption; and TRPV5, klotho, and Npt2c to regulate renal calcium and phosphate reabsorption. VDR appears to function unliganded by 1,25D in keratinocytes to drive mammalian hair cycling via regulation of genes such as CASP14, S100A8, SOSTDC1, and others affecting Wnt signaling. Finally, alternative, low-affinity, non-vitamin D VDR ligands, e.g., lithocholic acid, docosahexaenoic acid, and curcumin, have been reported. Combined alternative VDR ligand(s) and 1,25D/VDR control of gene expression may delay chronic disorders of aging such as osteoporosis, type 2 diabetes, cardiovascular disease, and cancer.

Serum high-density lipoprotein cholesterol, metabolic profile, and breast cancer risk.

BACKGROUND The prevalence of metabolic syndrome (obesity, glucose intolerance, low serum high-density lipoprotein cholesterol [HDL-C], high serum triglycerides, hypertension) is high and increasing in parallel with an increasing breast cancer incidence worldwide. HDL-C represents an important aspect of the syndrome, yet its role in breast cancer is still undefined. METHODS In two population-based screening surveys during 1977-1983 and 1985-1987, serum HDL-C was assayed enzymatically among 38,823 Norwegian women aged 17-54 years at entry. Height, weight, blood pressure, serum lipids, fat and energy intake, physical activity, parity, oral contraceptive use, hormone therapy use, alcohol intake, and tobacco use were also assessed. We used Cox proportional hazards modeling to estimate the relative risk (RR) of breast cancer associated with serum HDL-C levels and to adjust for potential confounding variables. We performed stratified analyses to evaluate effect modification by body mass index (BMI) and menopausal status. All statistical tests were two-sided. RESULTS During a median follow-up of 17.2 years, we identified 708 cases of invasive breast cancer. In multivariable analysis, the risk of postmenopausal breast cancer was inversely related to quartile of HDL-C (P(trend) =.02). Among women with HDL-C above 1.64 mmol/L (highest quartile) versus below 1.20 mmol/L (lowest quartile), the relative risk was 0.75 (95% confidence interval [CI] = 0.58 to 0.97). The HDL-C association was confined to women in the heavier subgroup (BMI > or =25 kg/m2), for whom the relative risk of postmenopausal breast cancer in those with HDL-C above 1.64 mmol/L versus below 1.20 mmol/L was 0.43 (95% CI = 0.28 to 0.67; P(trend)<.001; P(interaction) =.001). CONCLUSION Low HDL-C, as part of the metabolic syndrome, is associated with increased postmenopausal breast cancer risk.

Midlife Serum Cholesterol and Increased Risk of Alzheimer’s and Vascular Dementia Three Decades Later

Aims: To investigate midlife cholesterol in relation to Alzheimer’s disease (AD) and vascular dementia (VaD) in a large multiethnic cohort of women and men. Methods: The Kaiser Permanente Northern California Medical Group (healthcare delivery organization) formed the database for this study. The 9,844 participants underwent detailed health evaluations during 1964–1973 at ages 40–45 years; they were still members of the health plan in 1994. AD and VaD were ascertained by medical records between 1 January 1994 and 1 June 2007. Cox proportional hazards models – adjusted for age, education, race/ethnic group, sex, midlife diabetes, hypertension, BMI and late-life stroke – were conducted. Results: In total, 469 participants had AD and 127 had VaD. With desirable cholesterol levels (<200 mg/dl) as a reference, hazard ratios (HR) and 95% CI for AD were 1.23 (0.97–1.55) and 1.57 (1.23–2.01) for borderline (200–239 mg/dl) and high cholesterol (≥240 mg/dl), respectively. HR and 95% CI for VaD were 1.50 (1.01–2.23) for borderline and 1.26 (0.82–1.96) for high cholesterol. Further analyses for AD (cholesterol quartiles, 1st quartile reference) indicated that cholesterol levels >220 mg/dl were a significant risk factor: HR were 1.31 (1.01–1.71; 3rd quartile, 221–248 mg/dl) and 1.58 (1.22–2.06; 4th quartile, 249–500 mg/dl). Conclusion: Midlife serum total cholesterol was associated with an increased risk of AD and VaD. Even moderately elevated cholesterol increased dementia risk. Dementia risk factors need to be addressed as early as midlife, before underlying disease(s) or symptoms appear.

Vegetarian dietary patterns and mortality in Adventist Health Study 2.

IMPORTANCE Some evidence suggests vegetarian dietary patterns may be associated with reduced mortality, but the relationship is not well established. OBJECTIVE To evaluate the association between vegetarian dietary patterns and mortality. DESIGN Prospective cohort study; mortality analysis by Cox proportional hazards regression, controlling for important demographic and lifestyle confounders. SETTING Adventist Health Study 2 (AHS-2), a large North American cohort. PARTICIPANTS A total of 96,469 Seventh-day Adventist men and women recruited between 2002 and 2007, from which an analytic sample of 73,308 participants remained after exclusions. EXPOSURES Diet was assessed at baseline by a quantitative food frequency questionnaire and categorized into 5 dietary patterns: nonvegetarian, semi-vegetarian, pesco-vegetarian, lacto-ovo-vegetarian, and vegan. MAIN OUTCOME AND MEASURE The relationship between vegetarian dietary patterns and all-cause and cause-specific mortality; deaths through 2009 were identified from the National Death Index. RESULTS There were 2570 deaths among 73,308 participants during a mean follow-up time of 5.79 years. The mortality rate was 6.05 (95% CI, 5.82-6.29) deaths per 1000 person-years. The adjusted hazard ratio (HR) for all-cause mortality in all vegetarians combined vs nonvegetarians was 0.88 (95% CI, 0.80-0.97). The adjusted HR for all-cause mortality in vegans was 0.85 (95% CI, 0.73-1.01); in lacto-ovo-vegetarians, 0.91 (95% CI, 0.82-1.00); in pesco-vegetarians, 0.81 (95% CI, 0.69-0.94); and in semi-vegetarians, 0.92 (95% CI, 0.75-1.13) compared with nonvegetarians. Significant associations with vegetarian diets were detected for cardiovascular mortality, noncardiovascular noncancer mortality, renal mortality, and endocrine mortality. Associations in men were larger and more often significant than were those in women. CONCLUSIONS AND RELEVANCE Vegetarian diets are associated with lower all-cause mortality and with some reductions in cause-specific mortality. Results appeared to be more robust in males. These favorable associations should be considered carefully by those offering dietary guidance.

Young adolescents' nutrition assessment on computer (YANA-C)

Objective:To assess the relative validity and acceptability of the computerised 24-h recall ‘Young Adolescent's Nutrition Assessment on Computer (YANA-C)’.Design:Food and nutrient intakes assessed with YANA-C were compared with food records (study 1) and 24-h dietary recall interviews (study 2).Main outcome measures:Intakes of food groups (fruit, fruit juice, vegetables, potatoes, bread, cereals, milk, cheese, other milk products, soft drinks, diet soft drinks, sugar/sweets, pastry/cookies, savoury snacks, butter/sauces, eggs, fish, meat) and nutrients (energy, carbohydrates, protein, fat, fiber, calcium, vitamin C and iron).Subjects and setting:A total of 237 pupils (11–14 y) from two primary and four secondary schools (study 1: n=136; study 2: n=101) in Belgium-Flanders. Results:YANA-C proved to agree well with both standard methods in categorizing subjects in consumers and nonconsumers (κstudy 1=0.48–0.92; κstudy 2=0.38–0.90). Spearman's correlations for energy and nutrient intakes ranged between 0.44 and 0.79 for study 1 and between 0.44 and 0.86 for study 2. Nutrient and energy intakes were in general (excluding calcium) significantly higher in YANA-C in comparison with the food record, but not in comparison with the interview (only fiber). Statistics used to investigate whether YANA-C agreed with the other methods in ranking portions/amounts in consumers only were fair to moderate for most of the food groups (weighted κ study 1=0.11–0.55; study 2=0.04–0.73); amounts in consumers only, were significantly lower in YANA-C against both standards for cereals; amounts were significantly higher in YANA-C against the food record for milk, soft drinks, sugar/sweets and savoury snacks and against the interview for potatoes. Only a few pupils evaluated the program negatively. Conclusion:YANA-C is a promising method to collect detailed dietary information from young adolescents with relatively low staff resources, useful in many nutrition research applications.

Therapeutic equivalence of alendronate 70 mg once-weekly and alendronate 10 mg daily in the treatment of osteoporosis. Alendronate Once-Weekly Study Group.

Dosing convenience is a key element in the effective management of any chronic disease, and is particularly important in the long-term management of osteoporosis. Less frequent dosing with any medication may enhance compliance, thereby maximizing the effectiveness of therapy. Animal data support the rationale that once-weekly dosing with alendronate 70 mg (7 times the daily oral treatment dose) could provide similar efficacy to daily dosing with alendronate 10 mg due to its long duration of effect in bone. In addition, dog studies suggest that the potential for esophageal irritation, observed with daily oral bisphosphonates, may be substantially reduced with once-weekly dosing. This dosing regimen would provide patients with increased convenience and would be likely to enhance patient compliance. We compared the efficacy and safety of treatment with oral once-weekly alendronate 70 mg (N=519), twice-weekly alendronate 35 mg (N=369), and daily alendronate 10 mg (N=370) in a one-year, double-blind, multicenter study of postmenopausal women (ages 42 to 95) with osteoporosis (bone mineral density [BMD] of either lumbar spine or femoral neck at least 2.5 SDs below peak premenopausal mean, or prior vertebral or hip fracture). The primary efficacy endpoint was the comparability of increases in lumbar spine BMD, using strict pre-defined equivalence criteria. Secondary endpoints included changes in BMD at the hip and total body and rate of bone turnover, as assessed by biochemical markers. Both of the new regimens fully satisfied the equivalence criteria relative to daily therapy. Mean increases in lumbar spine BMD at 12 months were: 5.1% (95% CI 4.8, 5.4) in the 70 mg once-weekly group, 5.2% (4.9, 5.6) in the 35 mg twice-weekly group, and 5.4% (5.0, 5.8) in the 10 mg daily treatment group. Increases in BMD at the total hip, femoral neck, trochanter, and total body were similar for the three dosing regimens. All three treatment groups similarly reduced biochemical markers of bone resorption (urinary N-telopeptides of type I collagen) and bone formation (serum bone-specific alkaline phosphatase) into the middle of the premenopausal reference range. All treatment regimens were well tolerated with a similar incidence of upper GI adverse experiences. There were fewer serious upper GI adverse experiences and a trend toward a lower incidence of esophageal events in the once-weekly dosing group compared to the daily dosing group. These data are consistent with preclinical animal models, and suggest that once-weekly dosing has the potential for improved upper GI tolerability. Clinical fractures, captured as adverse experiences, were similar among the groups. We conclude that the alendronate 70 mg once-weekly dosing regimen will provide patients with a more convenient, therapeutically equivalent alternative to daily dosing, and may enhance compliance and long-term persistence with therapy.

Effect of supplemental zinc on the growth and serum zinc concentrations of prepubertal children: a meta-analysis of randomized controlled trials.

BACKGROUND Multiple studies have been carried out to assess the effect of zinc supplementation on children's growth. The results of these studies are inconsistent, and the factors responsible for these varied outcomes are unknown. OBJECTIVE Meta-analyses of randomized controlled intervention trials were therefore completed to assess the effect of zinc supplementation on the physical growth and serum zinc concentrations of prepubertal children. DESIGN A total of 33 acceptable studies with appropriate data were identified by MEDLINE (National Library of Medicine, Bethesda, MD) searches and other methods. Weighted mean effect sizes (expressed in SD units) were calculated for changes in height, weight, weight-for-height, and serum zinc concentration by using random-effects models; factors associated with effect sizes were explored by meta-regression techniques. RESULTS Zinc supplementation produced highly significant, positive responses in height and weight increments, with effect sizes of 0.350 (95% CI: 0.189, 0.511) and 0.309 (0.178, 0.439), respectively. There was no significant effect of zinc on weight-for-height indexes [weighted mean effect size: -0.018 (-0.132, 0.097)]. Zinc supplementation caused a large increase in the children's serum zinc concentrations, with an effect size of 0.820 (0.499, 1.14). Growth responses were greater in children with low initial weight-for-age z scores and in those aged >6 mo with low initial height-for-age z scores. CONCLUSIONS Interventions to improve children's zinc nutriture should be considered in populations at risk of zinc deficiency, especially where there are elevated rates of underweight or stunting. The population mean serum zinc concentration is a useful indicator of the successful delivery and absorption of zinc supplements in children.

Predictors of survival after acute paraquat poisoning.

Acute paraquat poisoning is often fatal. Many studies have investigated successful treatment modalities, but no standard treatment yet exists. The purpose of this study was to determine the predictors of survival after acute paraquat poisoning in 602 patients. The paraquat exposure was assessed based on the amount of ingested paraquat and a semiquantitative measure of the urine level of paraquat. Initial clinical parameters including vital signs, hemoglobin, white-blood-cell count, pH, PaCO2, PaO2, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, total bilirubin, amylase, and glucose were obtained at the time of arrival at the emergency room. Outcomes after acute paraquat poisoning were categorized as survivors and nonsurvivors. Multiple logistic regression analysis was applied to assess the predictors of survival after acute paraquat poisoning. Some patients (55.5%) survived after oral ingestion of paraquat, whereas all those exposed to paraquat percutaneous or inhalational route survived. The amount of paraquat (24.5% concentrate of 1,1'-dimethyl-4,4'-bipyridium dichloride) ingested was 45.6 +/- 74.1 mL (mean +/- SD). In addition to degree of paraquat exposure, survival after acute paraquat poisoning was associated with age, respiratory rate, pH, PaCO2, hemoglobin, white-blood-cell count, blood urea nitrogen, amylase, and the number of failed organs in multiple logistic regression analysis. In conclusion, young age, percutaneous or inhalational route, exposure to less paraquat, and lesser degrees of leukocytosis, acidosis, and renal, hepatic, and pancreatic failures on admission are good prognostic factors of survival after acute paraquat poisoning.

The intravascular volume effect of Ringer's lactate is below 20%: a prospective study in humans

INTRODUCTION Isotonic crystalloids play a central role in perioperative fluid management. Isooncotic preparations of colloids (for example, human albumin or hydroxyethyl starch) remain nearly completely intravascular when infused to compensate for acute blood losses. Recent data were interpreted to indicate a comparable intravascular volume effect for crystalloids, challenging the occasionally suggested advantage of using colloids to treat hypovolemia. General physiological knowledge and clinical experience, however, suggest otherwise. METHODS In a prospective study, double-tracer blood volume measurements were performed before and after intended normovolemic hemodilution in ten female adults, simultaneously substituting the three-fold amount of withdrawn blood with Ringer's lactate. Any originated deficits were substituted with half the volume of 20% human albumin, followed by a further assessment of blood volume. To assess significance between the measurements, repeated measures analysis of variance (ANOVA) according to Fisher were performed. If significant results were shown, paired t tests (according to Student) for the singular measurements were taken. P < 0.05 was considered to be significant. RESULTS A total of 1,097 ± 285 ml of whole blood were withdrawn (641 ± 155 ml/m(2) body surface area) and simultaneously replaced by 3,430 ± 806 ml of Ringer's lactate. All patients showed a significant decrease in blood volume after hemodilution (-459 ± 185 ml; P < 0.05) that did not involve relevant hemodynamical changes, and a significant increase in interstitial water content (+2,157 ± 606 ml; P < 0.05). The volume effect of Ringer's lactate was 17 ± 10%. The infusion of 245 ± 64 ml of 20% human albumin in this situation restored blood volume back to baseline values, the volume effect being 184 ± 63%. CONCLUSIONS Substitution of isolated intravascular deficits in cardiopulmonary healthy adults with the three-fold amount of Ringer's lactate impedes maintenance of intravascular normovolemia. The main side effect was an impressive interstitial fluid accumulation, which was partly restored by the intravenous infusion of 20% human albumin. We recommend to substitute the five-fold amount of crystalloids or to use an isooncotic preparation in the face of acute bleeding in patients where edema prevention might be advantageous.

Effect of alendronate on risk of fracture in women with low bone density but without vertebral fractures: results from the Fracture Intervention Trial.

CONTEXT Alendronate sodium reduces fracture risk in postmenopausal women who have vertebral fractures, but its effects on fracture risk have not been studied for women without vertebral fractures. OBJECTIVE To test the hypothesis that 4 years of alendronate would decrease the risk of clinical and vertebral fractures in women who have low bone mineral density (BMD) but no vertebral fractures. DESIGN Randomized, blinded, placebo-controlled trial. SETTING Eleven community-based clinical research centers. SUBJECTS Women aged 54 to 81 years with a femoral neck BMD of 0.68 g/cm2 or less (Hologic Inc, Waltham, Mass) but no vertebral fracture; 4432 were randomized to alendronate or placebo and 4272 (96%) completed outcome measurements at the final visit (an average of 4.2 years later). INTERVENTION All participants reporting calcium intakes of 1000 mg/d or less received a supplement containing 500 mg of calcium and 250 IU of cholecalciferol. Subjects were randomly assigned to either placebo or 5 mg/d of alendronate sodium for 2 years followed by 10 mg/d for the remainder of the trial. MAIN OUTCOME MEASURES Clinical fractures confirmed by x-ray reports, new vertebral deformities detected by morphometric measurements on radiographs, and BMD measured by dual x-ray absorptiometry. RESULTS Alendronate increased BMD at all sites studied (P<.001) and reduced clinical fractures from 312 in the placebo group to 272 in the intervention group, but not significantly so (14% reduction; relative hazard [RH], 0.86; 95% confidence interval [CI], 0.73-1.01). Alendronate reduced clinical fractures by 36% in women with baseline osteoporosis at the femoral neck (>2.5 SDs below the normal young adult mean; RH, 0.64; 95% CI, 0.50-0.82; treatment-control difference, 6.5%; number needed to treat [NNT], 15), but there was no significant reduction among those with higher BMD (RH, 1.08; 95% CI, 0.87-1.35). Alendronate decreased the risk of radiographic vertebral fractures by 44% overall (relative risk, 0.56; 95% CI, 0.39-0.80; treatment-control difference, 1.7%; NNT, 60). Alendronate did not increase the risk of gastrointestinal or other adverse effects. CONCLUSIONS In women with low BMD but without vertebral fractures, 4 years of alendronate safely increased BMD and decreased the risk of first vertebral deformity. Alendronate significantly reduced the risk of clinical fractures among women with osteoporosis but not among women with higher BMD.

Vitamin D: The "sunshine" vitamin.

Vitamin D insufficiency affects almost 50% of the population worldwide. An estimated 1 billion people worldwide, across all ethnicities and age groups, have a vitamin D deficiency (VDD). This pandemic of hypovitaminosis D can mainly be attributed to lifestyle (for example, reduced outdoor activities) and environmental (for example, air pollution) factors that reduce exposure to sunlight, which is required for ultraviolet-B (UVB)-induced vitamin D production in the skin. High prevalence of vitamin D insufficiency is a particularly important public health issue because hypovitaminosis D is an independent risk factor for total mortality in the general population. Current studies suggest that we may need more vitamin D than presently recommended to prevent chronic disease. As the number of people with VDD continues to increase, the importance of this hormone in overall health and the prevention of chronic diseases are at the forefront of research. VDD is very common in all age groups. As few foods contain vitamin D, guidelines recommended supplementation at suggested daily intake and tolerable upper limit levels. It is also suggested to measure the serum 25-hydroxyvitamin D level as the initial diagnostic test in patients at risk for deficiency. Treatment with either vitamin D2 or vitamin D3 is recommended for deficient patients. A meta-analysis published in 2007 showed that vitamin D supplementation was associated with significantly reduced mortality. In this review, we will summarize the mechanisms that are presumed to underlie the relationship between vitamin D and understand its biology and clinical implications.

Hyperglycemia is associated with increased bone mineral density and decreased trabecular bone score in elderly Japanese men: The Fujiwara-kyo osteoporosis risk in men (FORMEN) study.

PURPOSE Patients with type 2 diabetes mellitus (T2DM) have an increased fracture risk despite having higher areal bone mineral density (aBMD). This study aimed to clarify the association between glycemic and insulin resistance status and bone microarchitecture, and whether pentosidine and bone turnover markers play any roles in the association. METHODS A total of 2012 community-dwelling men aged ≥65years completed baseline measurements of spine aBMD, fasting plasma glucose (FPG) and serum insulin, hemoglobin A1c (HbA1c), osteocalcin, type I procollagen N-terminal propeptide, type I collagen C-terminal crosslinking telopeptide, tartrate-resistant acid phosphatase isoenzyme 5b, pentosidine, height and weight and an interview regarding past disease history. Homeostasis model assessment-insulin resistance (HOMA-IR) was also calculated. T2DM was defined as physician-diagnosed middle age or elderly-onset diabetes mellitus, or according to biochemical test results. To evaluate bone microarchitecture, trabecular bone score (TBS) was calculated at the same vertebrae as those used for aBMD measurement. RESULTS After excluding participants who had a disease history and/or were taking medications affecting bone metabolism, 1683 men (age, 72.9±5.2years) were analyzed. Men with T2DM had significantly higher aBMD compared to those without T2DM. There was no significant difference in TBS. However, FPG, HbA1c and HOMA-IR levels were significantly inversely correlated with TBS after adjusting for age, BMI and aBMD. Multivariate linear regression analyses revealed that glycemic indices (FPG and HbA1c) were significantly associated with increased aBMD and decreased TBS, and that HOMA-IR was associated only with TBS. These associations did not change after further adjusting for bone turnover makers and pentosidine levels. CONCLUSIONS Hyperglycemia and elevated insulin-resistance were associated with low TBS independently of bone turnover and pentosidine levels.

Accuracy of weighed dietary records in studies of diet and health.

OBJECTIVE To provide an independent evaluation of seven day weighed dietary records, which are currently accepted as the most accurate technique for assessing habitual dietary intake in studies investigating the links between diet and health. DESIGN Subjects who had previously participated in the Northern Ireland diet and health study were reselected by stratified random sampling to represent the range of energy intakes in the study as assessed by the seven day weighed dietary record. SETTING Northern Ireland. SUBJECTS 31 Free living adults (16 men and 15 women). MAIN OUTCOME MEASURES Energy intake as measured by the seven day weighed dietary record and total energy expenditure estimated concurrently by the doubly labelled water technique. RESULTS Average recorded energy intakes were significantly lower than measured expenditure in the group overall (9.66 MJ/day v 12.15 MJ/day, 95% confidence interval 1.45 to 3.53 MJ/day). Among those in the upper third of energy intakes the mean (SE) ratio of intake to expenditure was close to 1.0, indicating accurate records (men 1.01 (0.11), women 0.96 (0.08]. In the middle and lower thirds the ratios for men were only 0.74 (0.05) and 0.70 (0.07) respectively and for women 0.89 (0.07) and 0.61 (0.07). CONCLUSIONS These results show a serious bias in reporting habitual energy intake. If substantiated they may have wide implications for the interpretation of many nutritional studies.

Vitamins E and C in the prevention of prostate and total cancer in men: the Physicians' Health Study II randomized controlled trial.

CONTEXT Many individuals take vitamins in the hopes of preventing chronic diseases such as cancer, and vitamins E and C are among the most common individual supplements. A large-scale randomized trial suggested that vitamin E may reduce risk of prostate cancer; however, few trials have been powered to address this relationship. No previous trial in men at usual risk has examined vitamin C alone in the prevention of cancer. OBJECTIVE To evaluate whether long-term vitamin E or C supplementation decreases risk of prostate and total cancer events among men. DESIGN, SETTING, AND PARTICIPANTS The Physicians' Health Study II is a randomized, double-blind, placebo-controlled factorial trial of vitamins E and C that began in 1997 and continued until its scheduled completion on August 31, 2007. A total of 14,641 male physicians in the United States initially aged 50 years or older, including 1307 men with a history of prior cancer at randomization, were enrolled. INTERVENTION Individual supplements of 400 IU of vitamin E every other day and 500 mg of vitamin C daily. MAIN OUTCOME MEASURES Prostate and total cancer. RESULTS During a mean follow-up of 8.0 years, there were 1008 confirmed incident cases of prostate cancer and 1943 total cancers. Compared with placebo, vitamin E had no effect on the incidence of prostate cancer (active and placebo vitamin E groups, 9.1 and 9.5 events per 1000 person-years; hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.85-1.09; P = .58) or total cancer (active and placebo vitamin E groups, 17.8 and 17.3 cases per 1000 person-years; HR, 1.04; 95% CI, 0.95-1.13; P = .41). There was also no significant effect of vitamin C on total cancer (active and placebo vitamin C groups, 17.6 and 17.5 events per 1000 person-years; HR, 1.01; 95% CI, 0.92-1.10; P = .86) or prostate cancer (active and placebo vitamin C groups, 9.4 and 9.2 cases per 1000 person-years; HR, 1.02; 95% CI, 0.90-1.15; P = .80). Neither vitamin E nor vitamin C had a significant effect on colorectal, lung, or other site-specific cancers. Adjustment for adherence and exclusion of the first 4 or 6 years of follow-up did not alter the results. Stratification by various cancer risk factors demonstrated no significant modification of the effect of vitamin E on prostate cancer risk or either agent on total cancer risk. CONCLUSIONS In this large, long-term trial of male physicians, neither vitamin E nor C supplementation reduced the risk of prostate or total cancer. These data provide no support for the use of these supplements for the prevention of cancer in middle-aged and older men. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00270647.

Zinc supplementation during lactation: effects on maternal status and milk zinc concentrations.

The effects of a zinc supplement on maternal zinc status and milk zinc concentrations through > or = 7 mo of lactation were examined. Seventy-one lactating women received either a daily 15-mg zinc supplement (ZS, n = 40) or placebo (NZS, n = 31) started by 2 wk postpartum in a double-blind, randomized design. Overall mean zinc intakes were 13.0 +/- 3.4 mg/d for the NZS group and 25.7 +/- 3.9 mg/d (including supplement) for the ZS group. Plasma zinc concentrations of the ZS group were significantly higher than those of the NZS group (P = 0.05). Milk zinc concentrations declined significantly over the course of the study for all subjects but were not affected by zinc supplementation. The mean dietary zinc intake observed in the nonsupplemented group was adequate to maintain normal maternal zinc status and milk zinc concentrations through > or = 7 mo lactation. Similar controlled intervention trials in less well-nourished populations will be required to assess the impact of lower zinc intakes on milk zinc concentrations.

Diverse interventions that extend mouse lifespan suppress shared age-associated epigenetic changes at critical gene regulatory regions

BACKGROUND Age-associated epigenetic changes are implicated in aging. Notably, age-associated DNA methylation changes comprise a so-called aging "clock", a robust biomarker of aging. However, while genetic, dietary and drug interventions can extend lifespan, their impact on the epigenome is uncharacterised. To fill this knowledge gap, we defined age-associated DNA methylation changes at the whole-genome, single-nucleotide level in mouse liver and tested the impact of longevity-promoting interventions, specifically the Ames dwarf Prop1 df/df mutation, calorie restriction and rapamycin. RESULTS In wild-type mice fed an unsupplemented ad libitum diet, age-associated hypomethylation was enriched at super-enhancers in highly expressed genes critical for liver function. Genes harbouring hypomethylated enhancers were enriched for genes that change expression with age. Hypermethylation was enriched at CpG islands marked with bivalent activating and repressing histone modifications and resembled hypermethylation in liver cancer. Age-associated methylation changes are suppressed in Ames dwarf and calorie restricted mice and more selectively and less specifically in rapamycin treated mice. CONCLUSIONS Age-associated hypo- and hypermethylation events occur at distinct regulatory features of the genome. Distinct longevity-promoting interventions, specifically genetic, dietary and drug interventions, suppress some age-associated methylation changes, consistent with the idea that these interventions exert their beneficial effects, in part, by modulation of the epigenome. This study is a foundation to understand the epigenetic contribution to healthy aging and longevity and the molecular basis of the DNA methylation clock.

Vegetarian diet improves insulin resistance and oxidative stress markers more than conventional diet in subjects with Type 2 diabetes

AIMS The aim of this study was to compare the effects of calorie-restricted vegetarian and conventional diabetic diets alone and in combination with exercise on insulin resistance, visceral fat and oxidative stress markers in subjects with Type 2 diabetes. METHODS A 24-week, randomized, open, parallel design was used. Seventy-four patients with Type 2 diabetes were randomly assigned to either the experimental group (n = 37), which received a vegetarian diet, or the control group (n = 37), which received a conventional diabetic diet. Both diets were isocaloric, calorie restricted (-500 kcal/day). All meals during the study were provided. The second 12 weeks of the diet were combined with aerobic exercise. Participants were examined at baseline, 12 weeks and 24 weeks. Primary outcomes were: insulin sensitivity measured by hyperinsulinaemic isoglycaemic clamp; volume of visceral and subcutaneous fat measured by magnetic resonance imaging; and oxidative stress measured by thiobarbituric acid reactive substances. Analyses were by intention to treat. RESULTS Forty-three per cent of participants in the experimental group and 5% of participants in the control group reduced diabetes medication (P < 0.001). Body weight decreased more in the experimental group than in the control group [-6.2 kg (95% CI -6.6 to -5.3) vs. -3.2 kg (95% CI -3.7 to -2.5); interaction group × time P = 0.001]. An increase in insulin sensitivity was significantly greater in the experimental group than in the control group [30% (95% CI 24.5-39) vs. 20% (95% CI 14-25), P = 0.04]. A reduction in both visceral and subcutaneous fat was greater in the experimental group than in the control group (P = 0.007 and P = 0.02, respectively). Plasma adiponectin increased (P = 0.02) and leptin decreased (P = 0.02) in the experimental group, with no change in the control group. Vitamin C, superoxide dismutase and reduced glutathione increased in the experimental group (P = 0.002, P < 0.001 and P = 0.02, respectively). Differences between groups were greater after the addition of exercise training. Changes in insulin sensitivity and enzymatic oxidative stress markers correlated with changes in visceral fat. CONCLUSIONS A calorie-restricted vegetarian diet had greater capacity to improve insulin sensitivity compared with a conventional diabetic diet over 24 weeks. The greater loss of visceral fat and improvements in plasma concentrations of adipokines and oxidative stress markers with this diet may be responsible for the reduction of insulin resistance. The addition of exercise training further augmented the improved outcomes with the vegetarian diet.

Inhibition of receptor-mediated calcium influx in T cells by unsaturated non-esterified fatty acids.

The effect of omega-3, omega-6 and omega-9 unsaturated fatty acids (UFAs) on receptor-mediated Ca2+ entry was investigated in a T-cell line (JURKAT) by using anti-CD3 antibodies (OKT3) to induce intracellular Ca2+ [( Ca2+]i) increase and Ca2+ influx. All the UFAs, as well as Ni2+ ions and 12-O-tetradecanoylphorbol 13-acetate, decreased the OKT3-induced sustained [Ca2+]i increase to basal levels. Although non-esterified fatty acids activate protein kinase C (PKC) [McPhail, Clayton & Snyderman (1984) Science 224, 622-624; Murakami, Chan & Routtenberg (1986) J. Biol. Chem. 261, 15424-15429], studies using H-7 and analysis of the PKC-dependent phosphorylation of 19 and 80 kDa marker substrates ruled out the involvement of PKC in UFA-induced inhibition of Ca2+ entry. Flow-cytometry analysis showed that UFAs do not interfere with antibody-receptor binding. BSA (0.2%, w/v) reversed the effect of UFAs after these fatty acids have decreased the OKT3-induced [Ca2+]i increase to basal levels. The relevance of these findings and possible mechanisms for inhibition by UFAs of receptor-mediated Ca2+ influx were discussed.

Methionine restriction decreases visceral fat mass and preserves insulin action in aging male Fischer 344 rats independent of energy restriction.

Reduced dietary methionine intake (0.17% methionine, MR) and calorie restriction (CR) prolong lifespan in male Fischer 344 rats. Although the mechanisms are unclear, both regimens feature lower body weight and reductions in adiposity. Reduced fat deposition in CR is linked to preservation of insulin responsiveness in older animals. These studies examine the relationship between insulin responsiveness and visceral fat in MR and test whether, despite lower food intake observed in MR animals, decreased visceral fat accretion and preservation of insulin sensitivity is not secondary to CR. Accordingly, rats pair fed (pf) control diet (0.86% methinone, CF) to match the food intake of MR for 80 weeks exhibit insulin, glucose, and leptin levels similar to control-fed animals and comparable amounts of visceral fat. Conversely, MR rats show significantly reduced visceral fat compared to CF and PF with concomitant decreases in basal insulin, glucose, and leptin, and increased adiponectin and triiodothyronine. Daily energy expenditure in MR animals significantly exceeds that of both PF and CF. In a separate cohort, insulin responses of older MR animals as measured by oral glucose challenge are similar to young animals. Longitudinal assessments of MR and CF through 112 weeks of age reveal that MR prevents age-associated increases in serum lipids. By 16 weeks, MR animals show a 40% reduction in insulin-like growth factor-1 (IGF-1) that is sustained throughout life; CF IGF-1 levels decline much later, beginning at 112 weeks. Collectively, the results indicate that MR reduces visceral fat and preserves insulin activity in aging rats independent of energy restriction.

Dose-response study on thyrotoxic patients undergoing positron emission tomography and radioiodine therapy

With the acknowledged problems associated with assessment of functioning thyroid mass and hence radiation dose, our policy had been to give 75 MBq iodine-131 at 6-monthly intervals to patients with Graves' disease until they became euthyroid. Since positron emission tomography (PET) has been available at this hospital, the radiation dose to the thyroid has been calculated with an accuracy of ∼20%, the thyroid mass being determined from an iodine-124 PET scan. A dose-response study has been carried out on 65 patients who have received single or cumulative radiation doses of <80 Gy. The results show that patients who receive a low radiation dose (<20 Gy) at their first treatment have a high probability of remaining toxic at 12 months. In contrast, patients who receive higher radiation doses (>40 Gy) at their first treatment have a high probability of control. The probability of becoming euthyroid increases more rapidly with increasing radiation dose than the probability of becoming hypothyroid. Following this dose-response study, a new treatment protocol has been introduced. A 124I PET tracer study prior to 131I therapy will be performed to enable a prescribed thyroid dose of 50 Gy to be delivered to patients with Graves' disease. Further 131I therapy will only be considered if patients are still toxic at 12 months.

Endometrial carcinoma risk among women diagnosed with endometrial hyperplasia: the 34-year experience in a large health plan

Classifying endometrial hyperplasia (EH) according to the severity of glandular crowding (simple hyperplasia (SH) vs complex hyperplasia (CH)) and nuclear atypia (simple atypical hyperplasia (SAH) vs complex atypical hyperplasia (CAH)) should predict subsequent endometrial carcinoma risk, but data on progression are lacking. Our nested case–control study of EH progression included 138 cases, who were diagnosed with EH and then with carcinoma (1970–2003) at least 1 year (median, 6.5 years) later, and 241 controls, who were individually matched on age, date, and follow-up duration and counter-matched on EH classification. After centralised pathology panel and medical record review, we generated rate ratios (RRs) and 95% confidence intervals (CIs), adjusted for treatment and repeat biopsies. With disordered proliferative endometrium (DPEM) as the referent, AH significantly increased carcinoma risk (RR=14, 95% CI, 5–38). Risk was highest 1–5 years after AH (RR=48, 95% CI, 8–294), but remained elevated 5 or more years after AH (RR=3.5, 95% CI, 1.0–9.6). Progression risks for SH (RR=2.0, 95% CI, 0.9–4.5) and CH (RR=2.8, 95% CI, 1.0–7.9) were substantially lower and only slightly higher than the progression risk for DPEM. The higher progression risks for AH could foster management guidelines based on markedly different progression risks for atypical vs non-atypical EH.

Bone disease in pediatric patients undergoing dialysis with CAPD or CCPD.

The histologic features of renal osteodystrophy and the prevalence of bone aluminum deposition in children receiving regular dialysis have not been described. Forty-four pediatric patients undergoing continuous ambulatory (CAPD) or cycling (CCPD) peritoneal dialysis had bone biopsies and deferoxamine (DFO) infusion tests; all were receiving oral calcitriol. Osteitis fibrosa (OF) was found in 39%, mild lesions (M) in 25%, normal histology (NH) in 16%, aplastic lesions (AP) in 11%, and osteomalacia (OM) in 9%. Bone surface aluminum (SA) was present by histochemical staining in 10 out of 20 given aluminum-containing phosphate-binding agents and in 0 of 24 treated with calcium carbonate; chi 2 = 15.5, P less than 0.0001. Serum biochemistries and DFO infusion tests failed to predict bone histology, but plasma aluminum levels were markedly elevated and bone aluminum content was highest in patients with OM. Bone formation rate (BFR) correlated with serum parathyroid hormone (PTH), r = 0.55, P less than 0.001; BFR was inversely related to bone aluminum content (r = -0.42, P less than 0.01), even in patients with OF (r = -0.66, P less than 0.05). All patients with SA greater than 30% had normal or reduced BFR when compared to those with SA less than 30%; chi 2 = 12.2, P less than 0.005. Based on SA greater than 30%, six patients were classified as aluminum-related bone disease: three OM, one AP, and two NH. Two-thirds of pediatric patients undergoing CAPD/CCPD have persistent hyperparathyroidism despite treatment with calcitriol, but aluminum can adversely affect BFR when SA exceeds 30% regardless of histologic lesion or serum PTH level.

Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship.

IMPORTANCE The 2008 Physical Activity Guidelines for Americans recommended a minimum of 75 vigorous-intensity or 150 moderate-intensity minutes per week (7.5 metabolic-equivalent hours per week) of aerobic activity for substantial health benefit and suggested additional benefits by doing more than double this amount. However, the upper limit of longevity benefit or possible harm with more physical activity is unclear. OBJECTIVE To quantify the dose-response association between leisure time physical activity and mortality and define the upper limit of benefit or harm associated with increased levels of physical activity. DESIGN, SETTING, AND PARTICIPANTS We pooled data from 6 studies in the National Cancer Institute Cohort Consortium (baseline 1992-2003). Population-based prospective cohorts in the United States and Europe with self-reported physical activity were analyzed in 2014. A total of 661,137 men and women (median age, 62 years; range, 21-98 years) and 116,686 deaths were included. We used Cox proportional hazards regression with cohort stratification to generate multivariable-adjusted hazard ratios (HRs) and 95% CIs. Median follow-up time was 14.2 years. EXPOSURES Leisure time moderate- to vigorous-intensity physical activity. MAIN OUTCOMES AND MEASURES The upper limit of mortality benefit from high levels of leisure time physical activity. RESULTS Compared with individuals reporting no leisure time physical activity, we observed a 20% lower mortality risk among those performing less than the recommended minimum of 7.5 metabolic-equivalent hours per week (HR, 0.80 [95% CI, 0.78-0.82]), a 31% lower risk at 1 to 2 times the recommended minimum (HR, 0.69 [95% CI, 0.67-0.70]), and a 37% lower risk at 2 to 3 times the minimum (HR, 0.63 [95% CI, 0.62-0.65]). An upper threshold for mortality benefit occurred at 3 to 5 times the physical activity recommendation (HR, 0.61 [95% CI, 0.59-0.62]); however, compared with the recommended minimum, the additional benefit was modest (31% vs 39%). There was no evidence of harm at 10 or more times the recommended minimum (HR, 0.69 [95% CI, 0.59-0.78]). A similar dose-response relationship was observed for mortality due to cardiovascular disease and to cancer. CONCLUSIONS AND RELEVANCE Meeting the 2008 Physical Activity Guidelines for Americans minimum by either moderate- or vigorous-intensity activities was associated with nearly the maximum longevity benefit. We observed a benefit threshold at approximately 3 to 5 times the recommended leisure time physical activity minimum and no excess risk at 10 or more times the minimum. In regard to mortality, health care professionals should encourage inactive adults to perform leisure time physical activity and do not need to discourage adults who already participate in high-activity levels.

Glucose tolerance and blood pressure: long term follow up in middle aged men.

OBJECTIVE to investigate the role of glucose tolerance in the development of hypertension. DESIGN Retrospective analysis of the results of a health check up in a group of clinically healthy middle aged men in the late 1960s (median year 1968). The subjects were invited to enter into a primary prevention trial for cardiovascular disease in 1974, when they underwent clinical examination for risk factors. The trial was completed in 1979, when the men were re-examined. Follow up was in 1986. SETTING Institute of Occupational Health, Helsinki, Finland and second department of medicine, University of Helsinki. SUBJECTS In all, 3490 men born during 1919-34 participated in a health check up in the late 1960s. In 1974, 1815 of these men who were clinically healthy were entered into a primary prevention trial for cardiovascular disease. On clinical examination 1222 of the men were considered at high risk of cardiovascular disease. Of these, 612 received an intervention and were excluded from the study. A total of 593 men were without risk factors. The study comprised all of the men who did not have an intervention (n = 1203). In 1979, 1120 men were re-examined, and in 1986 945 men attended follow up. There were two groups for analysis: one comprising all subjects and the other comprising only men who were normotensive in 1968 and for whom complete information was available. INTERVENTIONS By 1979, 103 men were taking antihypertensive drugs, and by 1986, 131 were taking antihypertensive drugs and 12 were taking drugs for hyperglycaemia. MAIN OUTCOME MEASURES Blood glucose concentration one hour after a glucose load, blood pressure, and body weight were measured in 1968, 1974, and 1979. In 1986 blood pressure and body weight were recorded. RESULTS Men who were hypertensive in 1986 had significantly higher blood pressures (p less than 0.0001) and (after adjustment for body mass index and alcohol intake) significantly higher blood glucose concentrations one hour after a glucose load at all examinations than those who were normotensive in 1986. Regression analysis showed that the higher the blood glucose concentration after a glucose load in 1968 the higher the blood pressure during the following years. Those men between the second and third tertiles of blood glucose concentration in 1968 had a significantly higher risk of developing hypertension (odds ratio 1.71, 95% confidence interval 1.05 to 2.77) compared with those below the first tertile. CONCLUSION In this study men who developed hypertension tended to have shown an increased intolerance to glucose up to 18 years before the clinical manifestation of their disorder. Blood glucose concentration one hour after a glucose load was an independent predictor of future hypertension.

Prevention of radiographic-contrast-agent-induced reductions in renal function by acetylcysteine.

BACKGROUND Radiographic contrast agents can cause a reduction in renal function that may be due to reactive oxygen species. Whether the reduction can be prevented by the administration of antioxidants is unknown. METHODS We prospectively studied 83 patients with chronic renal insufficiency (mean [+/-SD] serum creatinine concentration, 2.4+/-1.3 mg per deciliter [216+/-116 micromol per liter]) who were undergoing computed tomography with a nonionic, low-osmolality contrast agent. Patients were randomly assigned either to receive the antioxidant acetylcysteine (600 mg orally twice daily) and 0.45 percent saline intravenously, before and after administration of the contrast agent, or to receive placebo and saline. RESULTS Ten of the 83 patients (12 percent) had an increase of at least 0.5 mg per deciliter (44 micromol per liter) in the serum creatinine concentration 48 hours after administration of the contrast agent: 1 of the 41 patients in the acetylcysteine group (2 percent) and 9 of the 42 patients in the control group (21 percent; P=0.01; relative risk, 0.1; 95 percent confidence interval, 0.02 to 0.9). In the acetylcysteine group, the mean serum creatinine concentration decreased significantly (P<0.001), from 2.5+/-1.3 to 2.1+/-1.3 mg per deciliter (220+/-118 to 186+/-112 micromol per liter) 48 hours after the administration of the contrast medium, whereas in the control group, the mean serum creatinine concentration increased nonsignificantly (P=0.18), from 2.4+/-1.3 to 2.6+/-1.5 mg per deciliter (212+/-114 to 226+/-133 micromol per liter) (P<0.001 for the comparison between groups). CONCLUSIONS Prophylactic oral administration of the antioxidant acetylcysteine, along with hydration, prevents the reduction in renal function induced by contrast agents in patients with chronic renal insufficiency.

Update on technical issues concerning complementary feeding of young children in developing countries and implications for intervention programs.

This paper provides an update to the 1998 WHO/UNICEF report on complementary feeding. New research findings are generally consistent with the guidelines in that report, but the adoption of new energy and micronutrient requirements for infants and young children will result in lower recommendations regarding minimum meal frequency and energy density of complementary foods, and will alter the list of "problem nutrients. " Without fortification, the densities of iron, zinc, and vitamin B6 in complementary foods are often inadequate, and the intake of other nutrients may also be low in some populations. Strategies for obtaining the needed amounts of problem nutrients, as well as optimizing breastmilk intake when other foods are added to the diet, are discussed. The impact of complementary feeding interventions on child growth has been variable, which calls attention to the need for more comprehensive programs. A six-step approach to planning, implementing, and evaluating such programs is recommended.

Dietary saturated and unsaturated fats as determinants of blood pressure and vascular function.

The amount and type of dietary fat have long been associated with the risk of CVD. Arterial stiffness and endothelial dysfunction are important risk factors in the aetiology of CHD. A range of methods exists to assess vascular function that may be used in nutritional science, including clinic and ambulatory blood pressure monitoring, pulse wave analysis, pulse wave velocity, flow-mediated dilatation and venous occlusion plethysmography. The present review focuses on the quantity and type of dietary fat and effects on blood pressure, arterial compliance and endothelial function. Concerning fat quantity, the amount of dietary fat consumed habitually appears to have little influence on vascular function independent of fatty acid composition, although single high-fat meals postprandially impair endothelial function compared with low-fat meals. The mechanism is related to increased circulating lipoproteins and NEFA which may induce pro-inflammatory pathways and increase oxidative stress. Regarding the type of fat, cross-sectional data suggest that saturated fat adversely affects vascular function whereas polyunsaturated fat (mainly linoleic acid (18 : 2n-6) and n-3 PUFA) are beneficial. EPA (20 : 5n-3) and DHA (22 : 6n-3) can reduce blood pressure, improve arterial compliance in type 2 diabetics and dyslipidaemics, and augment endothelium-dependent vasodilation. The mechanisms for this vascular protection, and the nature of the separate physiological effects induced by EPA and DHA, are priorities for future research. Since good-quality observational or interventional data on dietary fatty acid composition and vascular function are scarce, no further recommendations can be suggested in addition to current guidelines at the present time.

Laboratory prediction of the requirement for renal replacement in acute falciparum malaria

BACKGROUND Acute renal failure is a common complication of severe malaria in adults, and without renal replacement therapy (RRT), it carries a poor prognosis. Even when RRT is available, delaying its initiation may increase mortality. Earlier identification of patients who will need RRT may improve outcomes. METHOD Prospectively collected data from two intervention studies in adults with severe malaria were analysed focusing on laboratory features on presentation and their association with a later requirement for RRT. In particular, laboratory indices of acute tubular necrosis (ATN) and acute kidney injury (AKI) that are used in other settings were examined. RESULTS Data from 163 patients were available for analysis. Whether or not the patients should have received RRT (a retrospective assessment determined by three independent reviewers) was used as the reference. Forty-three (26.4%) patients met criteria for dialysis, but only 19 (44.2%) were able to receive this intervention due to the limited availability of RRT. Patients with impaired renal function on admission (creatinine clearance < 60 ml/min) (n = 84) had their laboratory indices of ATN/AKI analysed. The plasma creatinine level had the greatest area under the ROC curve (AUC): 0.83 (95% confidence interval 0.74-0.92), significantly better than the AUCs for, urinary sodium level, the urea to creatinine ratio (UCR), the fractional excretion of urea (FeUN) and the urinary neutrophil gelatinase-associated lipocalcin (NGAL) level. The AUC for plasma creatinine was also greater than the AUC for blood urea nitrogen level, the fractional excretion of sodium (FeNa), the renal failure index (RFI), the urinary osmolality, the urine to plasma creatinine ratio (UPCR) and the creatinine clearance, although the difference for these variables did not reach statistical significance. CONCLUSIONS In adult patients with severe malaria and impaired renal function on admission, none of the evaluated laboratory indices was superior to the plasma creatinine level when used to predict a later requirement for renal replacement therapy.

Role of common hypnotics on the phenotypic causes of obstructive sleep apnoea: paradoxical effects of zolpidem.

Hypnotics are contraindicated in obstructive sleep apnoea (OSA) because of concerns of pharyngeal muscle relaxation and delayed arousal worsening hypoxaemia. However, human data are lacking. This study aimed to determine the effects of three common hypnotics on the respiratory arousal threshold, genioglossus muscle responsiveness and upper airway collapsibility during sleep.21 individuals with and without OSA (18-65 years) completed 84 detailed sleep studies after receiving temazepam (10 mg), zolpidem (10 mg), zopiclone (7.5 mg) and placebo on four occasions in a randomised, double-blind, placebo-controlled, crossover trial (ACTRN12612001004853).The arousal threshold increased with zolpidem and zopiclone versus placebo (mean±sd -18.3±10 and -19.1±9 versus -14.6±7 cmH2O; p=0.02 and p<0.001) but not with temazepam (-16.8±9 cmH2O; p=0.17). Genioglossus muscle activity during stable non-REM sleep and responsiveness during airway narrowing was not different with temazepam and zopiclone versus placebo but, paradoxically, zolpidem increased median muscle responsiveness three-fold during airway narrowing (median -0.15 (interquartile range -1.01 to -0.04) versus -0.05 (-0.29 to -0.03)% maximum EMG per cmH2O epiglottic pressure; p=0.03). The upper airway critical closing pressure did not change with any of the hypnotics. These doses of common hypnotics have differential effects on the respiratory arousal threshold but do not reduce upper airway muscle activity or alter airway collapsibility during sleep. Rather, muscle activity increases during airway narrowing with zolpidem.

Outcome of pregnancy in women with moderate or severe renal insufficiency.

BACKGROUND Pregnant women with mild preexisting renal disease have relatively few complications of pregnancy, but the risks of maternal and obstetrical complications in women with moderate or severe renal insufficiency remain uncertain. METHODS We determined the frequency and types of maternal and obstetrical complications and the outcomes of pregnancy in 67 women with primary renal disease (82 pregnancies). All the women had initial serum creatinine concentrations of at least 1.4 mg per deciliter (124 mumol per liter) and gestations that continued beyond the first trimester. RESULTS The mean (+/- SD) serum creatinine concentration increased from 1.9 +/- 0.8 mg per deciliter (168 +/- 71 mumol per liter) in early pregnancy to 2.5 +/- 1.3 mg per deciliter (221 +/- 115 mumol per liter) in the third trimester. The frequency of hypertension rose from 28 percent at base line to 48 percent in the third trimester, and that of high-grade proteinuria (urinary protein excretion, > 3000 mg per liter) from 23 percent to 41 percent. For the 70 pregnancies (57 women) for which data were available during pregnancy and immediately post partum, pregnancy-related loss of maternal renal function occurred in 43 percent. Eight of these pregnancies (10 percent of the total) were associated with rapid acceleration of maternal renal insufficiency. Obstetrical complications included a high rate of preterm delivery (59 percent) and growth retardation (37 percent). The infant survival rate was 93 percent. CONCLUSIONS Among pregnant women with moderate or severe renal insufficiency, the rates of complications due to worsening renal function, hypertension, and obstetrical complications are increased, but fetal survival is high.

Protein restriction during pregnancy affects maternal liver lipid metabolism and fetal brain lipid composition in the rat.

Suboptimal developmental environments program offspring to lifelong metabolic problems. The aim of this study was to determine the impact of protein restriction in pregnancy on maternal liver lipid metabolism at 19 days of gestation (dG) and its effect on fetal brain development. Control (C) and restricted (R) mothers were fed with isocaloric diets containing 20 and 10% of casein. At 19 dG, maternal blood and livers and fetal livers and brains were collected. Serum insulin and leptin levels were determinate in mothers. Maternal and fetal liver lipid and fetal brain lipid quantification were performed. Maternal liver and fetal brain fatty acids were quantified by gas chromatography. In mothers, liver desaturase and elongase mRNAs were measured by RT-PCR. Maternal body and liver weights were similar in both groups. However, fat body composition, including liver lipids, was lower in R mothers. A higher fasting insulin at 19 dG in the R group was observed (C = 0.2 +/- 0.04 vs. R = 0.9 +/- 0.16 ng/ml, P < 0.01) and was inversely related to early growth retardation. Serum leptin in R mothers was significantly higher than that observed in C rats (C = 5 +/- 0.1 vs. R = 7 +/- 0.7 ng/ml, P < 0.05). In addition, protein restriction significantly reduced gene expression in maternal liver of desaturases and elongases and the concentration of arachidonic (AA) and docosahexanoic (DHA) acids. In fetus from R mothers, a low body weight (C = 3 +/- 0.3 vs. R = 2 +/- 0.1 g, P < 0.05), as well as liver and brain lipids, including the content of DHA in the brain, was reduced. This study showed that protein restriction during pregnancy may negatively impact normal fetal brain development by changes in maternal lipid metabolism.

Dietary status of trained female cyclists.

Dietary status was evaluated in eight highly trained female cyclists. Each cyclist kept a 3-day weighed food record. Diets were analyzed for nutrient content using a computerized software package. Blood was also obtained and evaluated for hemoglobin, hematocrit, and albumin. For an athletic group, the cyclists' diets were found to be low in energy (85% RDA) and carbohydrate (4.4 gm/kg body weight per day). Mean daily dietary intakes were well below the RDAs for folacin (76% RDA), magnesium (81%), iron (59%), and zinc (48%). In addition, more than one-third of the cyclists failed to consume 67% of the RDA for the following micronutrients: pyridoxine, folacin, cobalamin, vitamin E, magnesium, iron, and zinc. Hemoglobin (135 gm/L), hematocrit (0.39), and albumin (45 gm/L) values were all normal, although most hemoglobin values were in the lower 50% of normal range. Foods such as meats, poultry, fish, beans, peas, and nuts were low or absent from the diets of most athletes. Dietary quality in this group of female cyclists could have been greatly improved with the addition of more of those foods. These athletes could benefit from nutrition education and diet counseling.

Genome-Wide Gene-Sodium Interaction Analyses on Blood Pressure: The Genetic Epidemiology Network of Salt-Sensitivity Study.

We performed genome-wide analyses to identify genomic loci that interact with sodium to influence blood pressure (BP) using single-marker-based (1 and 2 df joint tests) and gene-based tests among 1876 Chinese participants of the Genetic Epidemiology Network of Salt-Sensitivity (GenSalt) study. Among GenSalt participants, the average of 3 urine samples was used to estimate sodium excretion. Nine BP measurements were taken using a random zero sphygmomanometer. A total of 2.05 million single-nucleotide polymorphisms were imputed using Affymetrix 6.0 genotype data and the Chinese Han of Beijing and Japanese of Tokyo HapMap reference panel. Promising findings (P<1.00×10(-4)) from GenSalt were evaluated for replication among 775 Chinese participants of the Multi-Ethnic Study of Atherosclerosis (MESA). Single-nucleotide polymorphism and gene-based results were meta-analyzed across the GenSalt and MESA studies to determine genome-wide significance. The 1 df tests identified interactions for UST rs13211840 on diastolic BP (P=3.13×10(-9)). The 2 df tests additionally identified associations for CLGN rs2567241 (P=3.90×10(-12)) and LOC105369882 rs11104632 (P=4.51×10(-8)) with systolic BP. The CLGN variant rs2567241 was also associated with diastolic BP (P=3.11×10(-22)) and mean arterial pressure (P=2.86×10(-15)). Genome-wide gene-based analysis identified MKNK1 (P=6.70×10(-7)), C2orf80 (P<1.00×10(-12)), EPHA6 (P=2.88×10(-7)), SCOC-AS1 (P=4.35×10(-14)), SCOC (P=6.46×10(-11)), CLGN (P=3.68×10(-13)), MGAT4D (P=4.73×10(-11)), ARHGAP42 (P≤1.00×10(-12)), CASP4 (P=1.31×10(-8)), and LINC01478 (P=6.75×10(-10)) that were associated with at least 1 BP phenotype. In summary, we identified 8 novel and 1 previously reported BP loci through the examination of single-nucleotide polymorphism and gene-based interactions with sodium.

Valvular interstitial cells suppress calcification of valvular endothelial cells.

BACKGROUND Calcific aortic valve disease (CAVD) is the most common heart valve disease in the Western world. We previously proposed that valvular endothelial cells (VECs) replenish injured adult valve leaflets via endothelial-to-mesenchymal transformation (EndMT); however, whether EndMT contributes to valvular calcification is unknown. We hypothesized that aortic VECs undergo osteogenic differentiation via an EndMT process that can be inhibited by valvular interstitial cells (VICs). APPROACH AND RESULTS VEC clones underwent TGF-β1-mediated EndMT, shown by significantly increased mRNA expression of the EndMT markers α-SMA (5.3 ± 1.2), MMP-2 (13.5 ± 0.6) and Slug (12 ± 2.1) (p < 0.05), (compared to unstimulated controls). To study the effects of VIC on VEC EndMT, clonal populations of VICs were derived from the same valve leaflets, placed in co-culture with VECs, and grown in control/TGF-β1 supplemented media. In the presence of VICs, EndMT was inhibited, shown by decreased mRNA expression of α-SMA (0.1 ± 0.5), MMP-2 (0.1 ± 0.1), and Slug (0.2 ± 0.2) (p < 0.05). When cultured in osteogenic media, VECs demonstrated osteogenic changes confirmed by increase in mRNA expression of osteocalcin (8.6 ± 1.3), osteopontin (3.7 ± 0.3), and Runx2 (5.5 ± 1.5). The VIC presence inhibited VEC osteogenesis, demonstrated by decreased expression of osteocalcin (0.4 ± 0.1) and osteopontin (0.2 ± 0.1) (p < 0.05). Time course analysis suggested that EndMT precedes osteogenesis, shown by an initial increase of α-SMA and MMP-2 (day 7), followed by an increase of osteopontin and osteocalcin (day 14). CONCLUSIONS The data indicate that EndMT may precede VEC osteogenesis. This study shows that VICs inhibit VEC EndMT and osteogenesis, indicating the importance of VEC-VIC interactions in valve homeostasis.

Low methionine ingestion by rats extends life span.

Dietary energy restriction has been a widely used means of experimentally extending mammalian life span. We report here that lifelong reduction in the concentration of a single dietary component, the essential amino acid L-methionine, from 0.86 to 0.17% of the diet results in a 30% longer life span of male Fischer 344 rats. Methionine restriction completely abolished growth, although food intake was actually greater on a body weight basis. Studies of energy consumption in early life indicated that the energy intake of 0.17% methionine-fed animals was near normal for animals of their size, although consumption per animal was below that of the much larger 0.86% methionine-fed rats. Increasing the energy intake of rats fed 0.17% methionine failed to increase their rate of growth, whereas restricting 0.85% methionine-fed rats to the food intake of 0.17% methionine-fed animals did not materially reduce growth, indicating that food restriction was not a factor in life span extension in these experiments. The biochemically well-defined pathways of methionine metabolism and utilization offer the potential for uncovering the precise mechanism(s) underlying this specific dietary restriction-related extension of life span.

Systematic review of role of bisphosphonates on skeletal morbidity in metastatic cancer.

OBJECTIVE To review the evidence for the use of bisphosphonates to reduce skeletal morbidity in cancer patients with bone metastases. DATA SOURCES Electronic databases, scanning reference lists, and consultation with experts and pharmaceutical companies. Foreign language papers were included. STUDY SELECTION Included trials were randomised controlled trials of patients with malignant disease and bone metastases who were treated with oral or intravenous bisphosphonate compared with another bisphosphonate, placebo, or standard care. All trials measured at least one outcome of skeletal morbidity. RESULTS 95 articles were identified; 30 studies fulfilled inclusion criteria. In studies that lasted > or = 6 months, compared with placebo bisphosphonates significantly reduced the odds ratio for fractures (vertebral 0.69, 95% confidence interval 0.57 to 0.84, P < 0.0001; non-vertebral 0.65, 0.54 to 0.79, P < 0.0001; combined 0.65, 0.55 to 0.78, P < 0.0001), radiotherapy (0.67, 0.57 to 0.79, P < 0.0001), and hypercalcaemia (0.54, 0.36 to 0.81, P = 0.003) but not for orthopaedic surgery (0.70, 0.46 to 1.05, P = 0.086) or spinal cord compression (0.71, 0.47 to 1.08, P = 0.113). The reduction in orthopaedic surgery was significant in studies that lasted over a year (0.59, 0.39 to 0.88, P = 0.009). Use of bisphosphonates significantly increased time to first skeletal related event but did not increase survival. Subanalyses showed that most evidence supports use of intravenous aminobisphosphonates. CONCLUSIONS In people with metastatic bone disease bisphosphonates significantly decrease skeletal morbidity, except for spinal cord compression and increased time to first skeletal related event. Treatment should start when bone metastases are diagnosed and continue until it is no longer clinically relevant.

Nitrite protects against morbidity and mortality associated with TNF- or LPS-induced shock in a soluble guanylate cyclase–dependent manner

Nitrite (NO(2)(-)), previously viewed as a physiologically inert metabolite and biomarker of the endogenous vasodilator NO, was recently identified as an important biological NO reservoir in vasculature and tissues, where it contributes to hypoxic signaling, vasodilation, and cytoprotection after ischemia-reperfusion injury. Reduction of nitrite to NO may occur enzymatically at low pH and oxygen tension by deoxyhemoglobin, deoxymyoglobin, xanthine oxidase, mitochondrial complexes, or NO synthase (NOS). We show that nitrite treatment, in sharp contrast with the worsening effect of NOS inhibition, significantly attenuates hypothermia, mitochondrial damage, oxidative stress and dysfunction, tissue infarction, and mortality in a mouse shock model induced by a lethal tumor necrosis factor challenge. Mechanistically, nitrite-dependent protection was not associated with inhibition of mitochondrial complex I activity, as previously demonstrated for ischemia-reperfusion, but was largely abolished in mice deficient for the soluble guanylate cyclase (sGC) alpha1 subunit, one of the principal intracellular NO receptors and signal transducers in the cardiovasculature. Nitrite could also provide protection against toxicity induced by Gram-negative lipopolysaccharide, although higher doses were required. In conclusion, we show that nitrite can protect against toxicity in shock via sGC-dependent signaling, which may include hypoxic vasodilation necessary to maintain microcirculation and organ function, and cardioprotection.

THE GLYOXAL BIS(2-HYDROXYANIL) METHOD MODIFIED FOR LOCALIZING INSOLUBLE CALCIUM SALTS.

TO enable staining of insoluble calcium salts with glyoxal bis(2-hydroxyanil) (GBHA), the original solution containing 2 ml of 0.4% GBHA in absolute ethanol, and 0.3 ml of aqueous 5% NaOH, and limited to staining only soluble calcium salts, was modified as follows: 1, 2 ml of 0.4% GBHA in absolute ethanol in 0.6 ml of 10% aqueous NaOH; 11, 0.1 gm GBHA in 2 ml of 3.4% NaOH in 75% ethanol. To prevent diffusion and loss of calcium, the tissues were processed by the freeze-substitution or freeze-dry method and sections stained without removing the paraffin. Modification I is effective only when 1 or 2 drops placed on the section are evaporated gradually to dryness, concentrating the GBHA and NaOH on the insoluble calcium salts. Modification II is effective when dried or poured on the the section and allowed to stain for 5 min. The stained slides are immersed for 15 min in 90% ethanol saturated with KCN and Na2CO3 for specificity to calcium; rinsed and counterstained in 95% ethanol containing 0.1% each of fast...

The effect of folic acid supplementation on plasma homocysteine in an elderly population.

BACKGROUND Increased plasma homocysteine is associated with coronary artery disease, peripheral vascular disease and venous thrombosis. Folic acid is the most effective therapy for reducing homocysteine levels. The lowest effective supplement of folic acid is not known, particularly for the elderly who have the highest prevalence of these conditions. AIM To explore the effects of daily supplements of 0, 50, 100, 200, 400 and 600 microg folic acid on plasma homocysteine in an elderly population. DESIGN Randomized double-blind placebo-controlled trial. METHODS Participants (n=368) aged 65-75 years were randomly allocated to receive one of the treatments for 6 weeks. Plasma homocysteine was recorded after 3 weeks and 6 weeks of supplementation. RESULTS Only the 400 microg and 600 microg groups had significantly lower homocysteine levels compared to placebo (p=0.038 and p<0.001, respectively). Using multiple linear regression and each individual's total folic acid intake (diet plus supplement), a total daily folic acid intake of 926 microg per day would be required to ensure that 95% of the elderly population would be without cardiovascular risk from folate deficiency. DISCUSSION A daily folic acid intake of 926 microg is unlikely to be achieved by diet alone. Individual supplementation or fortification of food with folic acid will be required to reach this target.

Hydroxyethyl starch (HES) versus other fluid therapies: effects on kidney function.

BACKGROUND Hydroxyethyl starches (HES) are synthetic colloids commonly used for fluid resuscitation, yet controversy exists about their impact on kidney function. OBJECTIVES To examine the effects of HES on kidney function compared to other fluid resuscitation therapies in different patient populations. SEARCH STRATEGY We searched the Cochrane Renal Group's specialised register, the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library), MEDLINE, EMBASE, MetaRegister and reference lists of articles. SELECTION CRITERIA Randomised controlled trials (RCTs) and quasi-RCTs in which HES was compared to an alternate fluid therapy for the prevention or treatment of effective intravascular volume depletion. Primary outcomes were renal replacement therapy (RRT), author-defined kidney failure and acute kidney injury (AKI) as defined by the RIFLE criteria. Secondary outcomes included serum creatinine and creatinine clearance. DATA COLLECTION AND ANALYSIS Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Preplanned sensitivity and subgroup analyses were performed after data were analysed with a random effects model. MAIN RESULTS The review included 34 studies (2607 patients). Overall, the RR of author-defined kidney failure was 1.50 (95% CI 1.20 to 1.87; n = 1199) and 1.38 for requiring RRT (95% CI 0.89 to 2.16; n = 1236) in HES treated individuals compared with other fluid therapies. Subgroup analyses suggested increased risk in septic patients compared to non-septic (surgical/trauma) patients. Non-septic patient studies were smaller and had lower event rates, so subgroup differences may have been due to lack of statistical power in these studies. Only limited data was obtained for analysis of kidney outcomes by the RIFLE criteria. Overall, methodological quality of studies was good but subjective outcomes were potentially biased because most studies were unblinded. AUTHORS' CONCLUSIONS Potential for increased risk of AKI should be considered when weighing the risks and benefits of HES for volume resuscitation, particularly in septic patients. Large studies with adequate follow-up are required to evaluate the renal safety of HES products in non-septic patient populations. RIFLE criteria should be applied to evaluate kidney function in future studies of HES and, where data is available, to re-analyse those studies already published. There is inadequate clinical data to address the claim that safety differences exist between different HES products.

Markers of myocardial damage and inflammation in relation to long-term mortality in unstable coronary artery disease. FRISC Study Group. Fragmin during Instability in Coronary Artery Disease.

BACKGROUND In patients with unstable coronary artery disease, there is a relation between the short-term risk of death and blood levels of troponin T (a marker of myocardial damage) and C-reactive protein and fibrinogen (markers of inflammation). Using information obtained during an extension of the follow-up period in the Fragmin during Instability in Coronary Artery Disease trial, we evaluated the usefulness of troponin T, C-reactive protein, and fibrinogen levels and other indicators of risk as predictors of the long-term risk of death from cardiac causes. METHODS Levels of C-reactive protein and fibrinogen at enrollment and the maximal level of troponin T during the first 24 hours after enrollment were analyzed in 917 patients included in a clinical trial of low-molecular-weight heparin in unstable coronary artery disease. The patients were followed for a mean of 37.0 months (range, 1.6 to 50.6). RESULTS During follow-up, 1.2 percent of the 173 patients with maximal blood troponin T levels of less than 0.06 microg per liter died of cardiac causes, as compared with 8.7 percent of the 367 patients with levels of 0.06 to 0.59 microg per liter and 15.4 percent of the 377 patients with levels of at least 0.60 microg per liter (P=0.007 and P=0.001, respectively). The rates of death from cardiac causes were 5.7 percent among the 314 patients with blood C-reactive protein levels of less than 2 mg per liter, 7.8 percent among the 294 with levels of 2 to 10 mg per liter, and 16.5 percent among the 309 with levels of more than 10 mg per liter (P=0.29 and P=0.001, respectively). The rates of death from cardiac causes were 5.4 percent among the 314 patients with blood fibrinogen levels of less than 3.4 g per liter, 12.0 percent among the 300 with levels of 3.4 to 3.9 g per liter, and 12.9 percent among the 303 with levels of at least 4.0 g per liter (P=0.004 and P=0.69, respectively). In a multivariate analysis, levels of troponin T and C-reactive protein were independent predictors of the risk of death from cardiac causes. CONCLUSIONS In unstable coronary artery disease, elevated levels of troponin T and C-reactive protein are strongly related to the long-term risk of death from cardiac causes. These markers are independent risk factors, and their effects are additive with respect to each other and other clinical indicators of risk.

Neurological development of 5-year-old children receiving a low-saturated fat, low-cholesterol diet since infancy: A randomized controlled trial.

CONTEXT Early childhood introduction of nutritional habits aimed at atherosclerosis prevention is compatible with normal growth, but its effect on neurological development is unknown. OBJECTIVE To analyze how parental counseling aimed at keeping children's diets low in saturated fat and cholesterol influences neurodevelopment during the first 5 years of life. DESIGN Randomized controlled trial conducted between February 1990 and November 1996. SETTING Outpatient clinic of a university department in Turku, Finland. PARTICIPANTS A total of 1062 seven-month-old infants and their parents, recruited at well-baby clinics between 1990 and 1992. At age 5 years, 496 children still living in the city of Turku were available to participate in neurodevelopmental testing. INTERVENTION Participants were randomly assigned to receive individualized counseling aimed at limiting the child's fat intake to 30% to 35% of daily energy, with a saturated:monounsaturated:polyunsaturated fatty acid ratio of 1:1:1 and a cholesterol intake of less than 200 mg/d (n = 540) or usual health education (control group, n = 522). MAIN OUTCOME MEASURES Nutrient intake, serum lipid concentrations, and neurological development at 5 years, among children in the intervention vs control groups. RESULTS Absolute and relative intakes of fat, saturated fatty acids, and cholesterol among children in the intervention group were markedly less than the respective values of control children. Mean (SD) percentages of daily energy at age 5 years for the intervention vs control groups were as follows: for total fat, 30.6% (4.5%) vs 33.4% (4.4%) (P<. 001); and for saturated fat, 11.7% (2.3%) vs 14.5% (2.4%) (P<.001). Mean intakes of cholesterol were 164.2 mg (60.1 mg) and 192.5 mg (71. 9 mg) (P<.001) for the intervention and control groups, respectively. Serum cholesterol concentrations were continuously 3% to 5% lower in children in the intervention group than in children in the control group. At age 5 years, mean (SD) serum cholesterol concentration of the intervention group was 4.27 (0.63) mmol/L (165 [24] mg/dL) and of the control group, 4.41 (0.74) mmol/L (170 [29] mg/dL) (P =.04). Neurological development of children in the intervention group was at least as good as that of children in the control group. Relative risks for children in the intervention group to fail tests of speech and language skills, gross motor functioning plus perception, and visual motor skills were 0.95 (90% confidence interval [CI], 0.60-1.49), 0.95 (90% CI, 0.58-1.55), and 0.65 (90% CI, 0.39-1.08), respectively (P =.85,.86, and.16, respectively, vs control children). CONCLUSION Our data indicate that repeated child-targeted dietary counseling of parents during the first 5 years of a child's life lessens age-associated increases in children's serum cholesterol and is compatible with normal neurological development. JAMA. 2000;284:993-1000

Use of serum C reactive protein and procalcitonin concentrations in addition to symptoms and signs to predict pneumonia in patients presenting to primary care with acute cough: diagnostic study

OBJECTIVES To quantify the diagnostic accuracy of selected inflammatory markers in addition to symptoms and signs for predicting pneumonia and to derive a diagnostic tool. DESIGN Diagnostic study performed between 2007 and 2010. Participants had their history taken, underwent physical examination and measurement of C reactive protein (CRP) and procalcitonin in venous blood on the day they first consulted, and underwent chest radiography within seven days. SETTING Primary care centres in 12 European countries. PARTICIPANTS Adults presenting with acute cough. MAIN OUTCOME MEASURES Pneumonia as determined by radiologists, who were blind to all other information when they judged chest radiographs. RESULTS Of 3106 eligible patients, 286 were excluded because of missing or inadequate chest radiographs, leaving 2820 patients (mean age 50, 40% men) of whom 140 (5%) had pneumonia. Re-assessment of a subset of 1675 chest radiographs showed agreement in 94% (κ 0.45, 95% confidence interval 0.36 to 0.54). Six published "symptoms and signs models" varied in their discrimination (area under receiver operating characteristics curve (ROC) ranged from 0.55 (95% confidence interval 0.50 to 0.61) to 0.71 (0.66 to 0.76)). The optimal combination of clinical prediction items derived from our patients included absence of runny nose and presence of breathlessness, crackles and diminished breath sounds on auscultation, tachycardia, and fever, with an ROC area of 0.70 (0.65 to 0.75). Addition of CRP at the optimal cut off of >30 mg/L increased the ROC area to 0.77 (0.73 to 0.81) and improved the diagnostic classification (net reclassification improvement 28%). In the 1556 patients classified according to symptoms, signs, and CRP >30 mg/L as "low risk" (<2.5%) for pneumonia, the prevalence of pneumonia was 2%. In the 132 patients classified as "high risk" (>20%), the prevalence of pneumonia was 31%. The positive likelihood ratio of low, intermediate, and high risk for pneumonia was 0.4, 1.2, and 8.6 respectively. Measurement of procalcitonin added no relevant additional diagnostic information. A simplified diagnostic score based on symptoms, signs, and CRP >30 mg/L resulted in proportions of pneumonia of 0.7%, 3.8%, and 18.2% in the low, intermediate, and high risk group respectively. CONCLUSIONS A clinical rule based on symptoms and signs to predict pneumonia in patients presenting to primary care with acute cough performed best in patients with mild or severe clinical presentation. Addition of CRP concentration at the optimal cut off of >30 mg/L improved diagnostic information, but measurement of procalcitonin concentration did not add clinically relevant information in this group.

Protection from olanzapine-induced metabolic toxicity in mice by acetaminophen and tetrahydroindenoindole

Objective:In mice and in humans, treatment with the second-generation antipsychotic drug olanzapine (OLZ) produces excessive weight gain, adiposity and secondary metabolic complications, including loss of glucose and insulin homeostasis. In mice consuming a high-fat (HF) diet, a similar phenotype develops, which is inhibited by the analgesic acetaminophen (APAP) and by the antioxidant tetrahydroindenoindole (THII). Therefore, we examined the ability of APAP and THII to prevent metabolic changes in mice receiving OLZ.Design and Measurement:C57BL/6J mice received either a normal diet or a HF diet, and were administered daily dosages of OLZ (3 mg kg−1 body weight), alone or with APAP (30 mg kg−1 body weight) or THII (4.5 mg kg−1 body weight), for 10 weeks. Parameters of body composition and metabolism, including glucose and insulin homeostasis and oxidative stress, were examined. Results:OLZ treatment doubled the HF diet-induced increases in body weight and percent body fat. These increases were partially prevented by both APAP and THII, although food consumption was constant in all groups. The THII protection was associated with an increase in whole body and mitochondrial respiration. OLZ also exacerbated, and both APAP and THII prevented, HF diet-induced loss of glucose tolerance and insulin resistance. As increased body fat promotes insulin resistance by a pathway involving oxidative stress, we evaluated production of reactive oxygen and lipid peroxidation in white adipose tissue (WAT). HF diet caused an increase in lipid peroxidation, NADPH-dependent O2 uptake and H2O2 production, which were further exacerbated by OLZ. APAP, THII and the NADPH oxidase inhibitor, diphenyleneiodonium chloride, each abolished oxidative stress in WAT.Conclusions:We conclude that both APAP and THII intervene in the development of obesity and metabolic complications associated with OLZ treatment.

Casual blood pressure and neurocognitive function in children with chronic kidney disease: a report of the children with chronic kidney disease cohort study.

BACKGROUND AND OBJECTIVES Children with chronic kidney disease (CKD) are at risk for cognitive dysfunction, and over half have hypertension. Data on the potential contribution of hypertension to CKD-associated neurocognitive deficits in children are limited. Our objective was to determine whether children with CKD and elevated BP (EBP) had decreased performance on neurocognitive testing compared with children with CKD and normal BP. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This was a cross-sectional analysis of the relation between auscultatory BP and neurocognitive test performance in children 6 to 17 years enrolled in the Chronic Kidney Disease in Children (CKiD) project. RESULTS Of 383 subjects, 132 (34%) had EBP (systolic BP and/or diastolic BP ≥90(th) percentile). Subjects with EBP had lower mean (SD) scores on Wechsler Abbreviated Scales of Intelligence (WASI) Performance IQ than those with normal BP (normal BP versus EBP, 96.1 (16.7) versus 92.4 (14.9), P = 0.03) and WASI Full Scale IQ (97.0 (16.2) versus 93.4 (16.5), P = 0.04). BP index (subject's BP/95(th) percentile BP) correlated inversely with Performance IQ score (systolic, r = -0.13, P = 0.01; diastolic, r = -0.19, P < 0.001). On multivariate analysis, the association between lower Performance IQ score and increased BP remained significant after controlling for demographic and disease-related variables (EBP, β = -3.7, 95% confidence interval [CI]: -7.3 to -0.06; systolic BP index, β = -1.16 to 95% CI: -2.1, -0.21; diastolic BP index, β = -1.17, 95% CI: -1.8 to -0.55). CONCLUSIONS Higher BP was independently associated with decreased WASI Performance IQ scores in children with mild-to-moderate CKD.

Incidence of childhood distal forearm fractures over 30 years: a population-based study.

CONTEXT The incidence of distal forearm fractures in children peaks around the time of the pubertal growth spurt, possibly because physical activity increases at the time of a transient deficit in cortical bone mass due to the increased calcium demand during maximal skeletal growth. Changes in physical activity or diet may therefore influence risk of forearm fracture. OBJECTIVE To determine whether there has been a change in the incidence of distal forearm fractures in children in recent years. DESIGN, SETTING, AND PATIENTS Population-based study among Rochester, Minn, residents younger than 35 years with distal forearm fractures in 1969-1971, 1979-1981, 1989-1991, and 1999-2001. MAIN OUTCOME MEASURE Estimated incidence of distal forearm fractures in 4 time periods. RESULTS Comparably age- and sex-adjusted annual incidence rates per 100 000 increased from 263.3 (95% confidence interval [CI], 231.1-295.4) in 1969-1971 to 322.3 (95% CI, 285.3-359.4) in 1979-1981 and to 399.8 (95% CI, 361.0-438.6) in 1989-1991 before leveling off at 372.9 (95% CI, 339.1-406.7) in 1999-2001. Age-adjusted incidence rates per 100 000 were 32% greater among male residents in 1999-2001 compared with 1969-1971 (409.4 [95% CI, 359.9-459.0] vs 309.4 [95% CI, 259.3-359.5]; P =.01) and 56% greater among female residents in the same time periods (334.3 [95% CI, 288.6-380.1] vs 214.6 [95% CI, 174.9-254.4]; P<.001). The peak incidence and greatest increase occurred between ages 11 and 14 years in boys and 8 and 11 years in girls. CONCLUSIONS There has been a statistically significant increase in the incidence of distal forearm fractures in children and adolescents, but whether this is due to changing patterns of physical activity, decreased bone acquisition due to poor calcium intake, or both is unclear at present. Given the large number of childhood fractures, however, studies are needed to define the cause(s) of this increase.

Vegan proteins may reduce risk of cancer, obesity, and cardiovascular disease by promoting increased glucagon activity.

Amino acids modulate the secretion of both insulin and glucagon; the composition of dietary protein therefore has the potential to influence the balance of glucagon and insulin activity. Soy protein, as well as many other vegan proteins, are higher in non-essential amino acids than most animal-derived food proteins, and as a result should preferentially favor glucagon production. Acting on hepatocytes, glucagon promotes (and insulin inhibits) cAMP-dependent mechanisms that down-regulate lipogenic enzymes and cholesterol synthesis, while up-regulating hepatic LDL receptors and production of the IGF-I antagonist IGFBP-1. The insulin-sensitizing properties of many vegan diets--high in fiber, low in saturated fat--should amplify these effects by down-regulating insulin secretion. Additionally, the relatively low essential amino acid content of some vegan diets may decrease hepatic IGF-I synthesis. Thus, diets featuring vegan proteins can be expected to lower elevated serum lipid levels, promote weight loss, and decrease circulating IGF-I activity. The latter effect should impede cancer induction (as is seen in animal studies with soy protein), lessen neutrophil-mediated inflammatory damage, and slow growth and maturation in children. In fact, vegans tend to have low serum lipids, lean physiques, shorter stature, later puberty, and decreased risk for certain prominent 'Western' cancers; a vegan diet has documented clinical efficacy in rheumatoid arthritis. Low-fat vegan diets may be especially protective in regard to cancers linked to insulin resistance--namely, breast and colon cancer--as well as prostate cancer; conversely, the high IGF-I activity associated with heavy ingestion of animal products may be largely responsible for the epidemic of 'Western' cancers in wealthy societies. Increased phytochemical intake is also likely to contribute to the reduction of cancer risk in vegans. Regression of coronary stenoses has been documented during low-fat vegan diets coupled with exercise training; such regimens also tend to markedly improve diabetic control and lower elevated blood pressure. Risk of many other degenerative disorders may be decreased in vegans, although reduced growth factor activity may be responsible for an increased risk of hemorrhagic stroke. By altering the glucagon/insulin balance, it is conceivable that supplemental intakes of key non-essential amino acids could enable omnivores to enjoy some of the health advantages of a vegan diet. An unnecessarily high intake of essential amino acids--either in the absolute sense or relative to total dietary protein--may prove to be as grave a risk factor for 'Western' degenerative diseases as is excessive fat intake.

Prediagnostic levels of C-peptide, IGF-I, IGFBP -1, -2 and -3 and risk of endometrial cancer.

Conditions related to chronic hyperinsulinemia, such as obesity, noninsulin dependent diabetes mellitus and polycystic ovary syndrome, are associated with an increased risk of endometrial cancer. Elevated plasma IGF-I and decreased levels of IGF-binding proteins have been shown to be associated with increased risk of several cancer types that are frequent in affluent societies. We investigated for the first time in a prospective study the association of pre-diagnostic blood concentrations of C-peptide (a marker of pancreatic insulin production), IGF-I, IGFBP-1, -2 and -3 with endometrial cancer risk. A case-control study was nested within 3 cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). It included 166 women with primary invasive endometrial cancer and 315 matched controls, of which 44 case and 78 control subjects were premenopausal at recruitment. Endometrial cancer risk increased with increasing levels of C-peptide (ptrend = 0.0002), up to an odds ratio (OR) of 4.76 [95% confidence interval (CI) = 1.91-11.8] for the highest quintile. This association remained after adjustment for BMI and other confounders [OR for the top quintile = 4.40 (1.65-11.7)]. IGFBP-1 levels were inversely related to endometrial cancer [ptrend = 0.002; OR in the upper quintile = 0.30 (0.15-0.62)], but the association was weakened and lost statistical significance after adjustment for confounders [ptrend = 0.06; OR in the upper quintile = 0.49 (0.22-1.07)]. Risk was unrelated to levels of IGF-I, IGFBP-2 and IGFBP-3. Chronic hyperinsulinemia, as reflected by increased circulating C-peptide, is associated with increased endometrial cancer risk. Decrease in the prevalence of chronic hyperinsulinemia, through changes in lifestyle or medication, is expected to prevent endometrial cancer.

High and low fat consumers, their macronutrient intake and body mass index: further analysis of the National Diet and Nutrition Survey of British Adults.

OBJECTIVES To explore the different characteristics of high and low fat consumers, in particular their macronutrient intake and body mass index. DESIGN Reanalysis of data from the Dietary and Nutritional Survey of British Adults. Comparisons were made between groups defined as high and low fat consumers on the basis of 7-day weighed food records considered to be valid for energy intake. Individuals were classified in two ways according to the percentage energy from fat (FAT%) and the absolute amount of fat consumed (FATg). The criteria for classification of the high FAT% being > 45% (high fat) and < or = 35% (low fat). For the FATg group the threshold for the high fat group was > 138 g/day (men) and > 102 g/day (women), and for the low fat group < 85 g/day (men) and < 70 g/day (women). SETTING Dietary data was collected from private households in Great Britain between 1986 and 1987. SUBJECTS From the total population of 2197, individuals who were slimming, ill or had an EI: BMR of < 1.2 were excluded in order to use data which was most likely to represent habitual energy intakes. From the remaining 1240 subjects, 10.8% of this sample (6.1% of the total population) were classified as low fat consumers (76 men and 58 women) and 15.4% high fat (8.7% of the total population, 93 men and 98 women). MAIN OUTCOME MEASURES Macronutrient consumption and body mass index (BMI). RESULTS 30% of the subjects changed fat group classification when the criteria of defining high and low fat groups altered from FAT% to FATg. Nutrient intakes differed according to definition of the groups. The high fat FATg group ate significantly more of all nutrients than the low fat FATg group. However, this was not seen for the FAT% analysis, with the high fat group eating more fat and less carbohydrate. The average BMI tended to be higher in the high fat than the low fat groups, particularly in the FATg analysis. However, the high fat group contained a wide range of BMIs. Further exploration of BMI in the high fat groups, showed that age (an 11-year difference) was the only variable to distinguish individuals in the top and bottom quartiles of BMI. CONCLUSIONS High and low fat consumers differ according to a number of variables, and this is affected by how these groups are defined (FAT% or FATg). High fat consumers tend to have a higher BMI than low fat consumers, but not all high fat consumers are overweight or obese.

Regulation of beta catenin signaling and parathyroid hormone anabolic effects in bone by the matricellular protein periostin.

Periostin (Postn) is a matricellular protein preferentially expressed by osteocytes and periosteal osteoblasts in response to mechanical stimulation and parathyroid hormone (PTH). Whether and how periostin expression influences bone anabolism, however, remains unknown. We investigated the skeletal response of adult Postn(-/-) and Postn(+/+) mice to intermittent PTH. Compared with Postn(+/+), Postn(-/-) mice had a lower bone mass, cortical bone volume, and strength response to PTH. PTH-stimulated bone-forming indices were all significantly lower in Postn(-/-) mice, particularly at the periosteum. Furthermore, in vivo stimulation of Wnt-β-catenin signaling by PTH, as evaluated in TOPGAL reporter mice, was inhibited in the absence of periostin (TOPGAL;Postn(-/-) mice). PTH stimulated periostin and inhibited MEF2C and sclerostin (Sost) expression in bone and osteoblasts in vitro. Recombinant periostin also suppressed Sost expression, which was mediated through the integrin αVβ3 receptor, whereas periostin-blocking antibody prevented inhibition of MEF2C and Sost by PTH. In turn, administration of a Sost-blocking antiboby partially restored the PTH-mediated increase in bone mass in Postn(-/-) mice. In addition, primary osteoblasts from Postn(-/-) mice showed a lower proliferation, mineralization, and migration, both spontaneously and in response to PTH. Osteoblastic gene expression levels confirmed a defect of Postn(-/-) osteoblast differentiation with and without PTH, as well as an increased osteoblast apoptosis in the absence of periostin. These data elucidate the complex role of periostin on bone anabolism, through the regulation of Sost, Wnt-β-catenin signaling, and osteoblast differentiation.

Risk of gestational hypertension in relation to folic acid supplementation during pregnancy.

The authors investigated the association between folic acid supplementation and gestational hypertension. The study population included women with nonmalformed infants in the United States and Canada who were participating in the Slone Epidemiology Center Birth Defects Study between 1993 and 2000. Women were interviewed within 6 months after delivery about sociodemographic and medical factors, the occurrence of hypertension with or without preeclampsia, and multivitamin use in pregnancy. Relative risks, adjusted for weight, parity, twin pregnancy, diabetes, smoking, education, and family income, were estimated using Cox regression models. Of 2,100 women, 204 (9.7%) reported gestational hypertension (onset after the 20th week of gestation). The multivariate-adjusted relative risk of developing gestational hypertension during the month after folic acid supplementation, compared with not using folic acid during that same month, was 0.55 (95% confidence interval: 0.39, 0.79). This finding suggests that folic acid-containing multivitamins may reduce the risk of gestational hypertension.

Composition of gall bladder stones associated with octreotide: response to oral ursodeoxycholic acid.

Octreotide, an effective treatment for acromegaly, induces gall bladder stones in 13-60% of patients. Because knowledge of stone composition is essential for studies of their pathogenesis, treatment, and prevention, this was investigated by direct and indirect methods in 14 octreotide treated acromegalic patients with gall stones. Chemical analysis of gall stones retrieved at cholecystectomy from two patients, showed that they contained 71% and 87% cholesterol by weight. In the remaining 12 patients, localised computed tomography of the gall bladder showed that eight had stones with maximum attenuation scores of < 100 Hounsfield units (values of < 100 HU predict cholesterol rich, dissolvable stones). Gall bladder bile was obtained by ultrasound guided, fine needle puncture from six patients. All six patients had supersaturated bile (mean (SEM) cholesterol saturation index of 1.19 (0.08) (range 1.01-1.53)) and all had abnormally rapid cholesterol microcrystal nucleation times (< 4 days (range 1-4)), whilst in four, the bile contained cholesterol microcrystals immediately after sampling. Of the 12 patients considered for oral ursodeoxycholic acid (UDCA) treatment, two had a blocked cystic duct and were not started on UDCA while one was lost to follow up. After one year of treatment, five of the remaining nine patients showed either partial (n = 3) or complete (n = 2) gall stone dissolution, suggesting that their stones were cholesterol rich. This corresponds, by actuarial (life table) analysis, to a combined gall stone dissolution rate of 58.3 (15.9%). In conclusion, octreotide induced gall stones are generally small, multiple, and cholesterol rich although, in common with spontaneous gall stone disease, at presentation some patients will have a blocked cystic duct and some gall stones containing calcium.

Effect of homocysteine lowering on mortality and vascular disease in advanced chronic kidney disease and end-stage renal disease: a randomized controlled trial.

CONTEXT High plasma homocysteine levels are a risk factor for mortality and vascular disease in observational studies of patients with chronic kidney disease. Folic acid and B vitamins decrease homocysteine levels in this population but whether they lower mortality is unknown. OBJECTIVE To determine whether high doses of folic acid and B vitamins administered daily reduce mortality in patients with chronic kidney disease. DESIGN, SETTING, AND PARTICIPANTS Double-blind randomized controlled trial (2001-2006) in 36 US Department of Veterans Affairs medical centers. Median follow-up was 3.2 years for 2056 participants aged 21 years or older with advanced chronic kidney disease (estimated creatinine clearance < or =30 mL/min) (n = 1305) or end-stage renal disease (n = 751) and high homocysteine levels (> or = 15 micromol/L). INTERVENTION Participants received a daily capsule containing 40 mg of folic acid, 100 mg of pyridoxine hydrochloride (vitamin B6), and 2 mg of cyanocobalamin (vitamin B12) or a placebo. MAIN OUTCOME MEASURES The primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke, amputation of all or part of a lower extremity, a composite of these 3 plus all-cause mortality, time to initiation of dialysis, and time to thrombosis of arteriovenous access in hemodialysis patients. RESULTS Mean baseline homocysteine level was 24.0 micromol/L in the vitamin group and 24.2 micromol/L in the placebo group. It was lowered 6.3 micromol/L (25.8%; P < .001) in the vitamin group and 0.4 micromol/L (1.7%; P = .14) in the placebo group at 3 months, but there was no significant effect on mortality (448 vitamin group deaths vs 436 placebo group deaths) (hazard ratio [HR], 1.04; 95% CI, 0.91-1.18). No significant effects were demonstrated for secondary outcomes or adverse events: there were 129 MIs in the vitamin group vs 150 for placebo (HR, 0.86; 95% CI, 0.67-1.08), 37 strokes in the vitamin group vs 41 for placebo (HR, 0.90; 95% CI, 0.58-1.40), and 60 amputations in the vitamin group vs 53 for placebo (HR, 1.14; 95% CI, 0.79-1.64). In addition, the composite of MI, stroke, and amputations plus mortality (P = .85), time to dialysis (P = .38), and time to thrombosis in hemodialysis patients (P = .97) did not differ between the vitamin and placebo groups. CONCLUSION Treatment with high doses of folic acid and B vitamins did not improve survival or reduce the incidence of vascular disease in patients with advanced chronic kidney disease or end-stage renal disease. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00032435.

Environmental factors that influence the cutaneous production of vitamin D

All vertebrates, including humans, obtain most of their daily vitamin D requirement from casual exposure to sunlight. During exposure to sunlight, the solar ultraviolet B photons (290-315 nm) penetrate into the skin where they cause the photolysis of 7-dehydrocholesterol to precholecalciferol. Once formed, precholecalciferol undergoes a thermally induced rearrangement of its double bonds to form cholecalciferol. An increase in skin pigmentation, aging, and the topical application of a sunscreen diminishes the cutaneous production of cholecalciferol. Latitude, season, and time of day as well as ozone pollution in the atmosphere influence the number of solar ultraviolet B photons that reach the earth's surface, and thereby, alter the cutaneous production of cholecalciferol. In Boston, exposure to sunlight during the months of November through February will not produce any significant amounts of cholecalciferol in the skin. Because windowpane glass absorbs ultraviolet B radiation, exposure of sunlight through glass windows will not result in any production of cholecalciferol. It is now recognized that vitamin D insufficiency and vitamin D deficiency are common in elderly people, especially in those who are infirm and not exposed to sunlight or who live at latitudes that do not provide them with sunlight-mediated cholecalciferol during the winter months. Vitamin D insufficiency and deficiency exacerbate osteoporosis, cause osteomalacia, and increase the risk of skeletal fractures. Vitamin D insufficiency and deficiency can be prevented by encouraging responsible exposure to sunlight and/or consumption of a multivitamin tablet that contains 10 micrograms (400 IU) vitamin D.

Obesity due to melanocortin 4 receptor (MC4R) deficiency is associated with increased linear growth and final height, fasting hyperinsulinemia, and incompletely suppressed growth hormone secretion.

CONTEXT Melanocortin receptor 4 (MC4R) deficiency is characterized by increased linear growth greater than expected for the degree of obesity. OBJECTIVE The objective of the investigation was to study the somatotroph axis in obese MC4R-deficient patients and equally obese controls. PATIENTS AND METHODS We obtained anthropometric measurements and insulin concentrations in 153 MC4R-deficient subjects and 1392 controls matched for age and severity of obesity. We measured fasting IGF-I, IGF-II, IGF binding protein (IGFBP)-1, IGFBP-3, and acid-labile subunit levels in a subset of 33 MC4R-deficient patients and 36 control subjects. We examined pulsatile GH secretion in six adult MC4R-deficient subjects and six obese controls. RESULTS Height sd score was significantly greater in MC4R-deficient children under 5 yr of age compared with controls (mean ± SEM: 2.3 ± 0.06 vs. 1.8 ± 0.04, P < 0.001), an effect that persisted throughout childhood. Final height (cm) was greater in MC4R-deficient men (mean ± SEM 173 ± 2.5 vs. 168 ± 2.1, P < 0.001) and women (mean 165 ± 2.1 vs. 158 ± 1.9, P < 0.001). Fasting IGF-I, IGF-II, acid-labile subunit, and IGFBP-3 concentrations were similar in the two groups. GH levels were markedly suppressed in obese controls, but pulsatile GH secretion was retained in MC4R deficiency. The mean maximal GH secretion rate per burst (P < 0.05) and mass per burst (P < 0.05) were increased in MC4R deficiency, consistent with increased pulsatile and total GH secretion. Fasting insulin levels were markedly elevated in MC4R-deficient children. CONCLUSIONS In MC4R deficiency, increased linear growth in childhood leads to increased adult final height, greater than predicted by obesity alone. GH pulsatility is maintained in MC4R deficiency, a finding consistent with animal studies, suggesting a role for MC4R in controlling hypothalamic somatostatinergic tone. Fasting insulin levels are significantly higher in children carrying MC4R mutations. Both of these factors may contribute to the accelerated growth phenotype characteristic of MC4R deficiency.

Up-regulation of neuronal calcium sensor-1 (NCS-1) in the prefrontal cortex of schizophrenic and bipolar patients.

The delineation of dopamine dysfunction in the mentally ill has been a long-standing quest of biological psychiatry. The present study focuses on a recently recognized group of dopamine receptor-interacting proteins as possible novel sites of dysfunction in schizophrenic and bipolar patients. We demonstrate that the dorsolateral prefrontal cortex in schizophrenia and bipolar cases from the Stanley Foundation Neuropathology Consortium display significantly elevated levels of the D2 dopamine receptor desensitization regulatory protein, neuronal calcium sensor-1. These levels of neuronal calcium sensor-1 were not influenced by age, gender, hemisphere, cause of death, postmortem period, alcohol consumption, or antipsychotic and mood stabilizing medications. The present study supports the hypothesis that schizophrenia and bipolar disorder may be associated with abnormalities in dopamine receptor-interacting proteins.

Alcohol, wine, and health

Abstract Background: For the past 20 years numerous epidemiological studies have correlated the consumption of alcohol and a variety of disease states: overall mortality, arteriosclerotic vascular diseases, hypertension, cancers, peptic ulcer, respiratory infections, gall stones, kidney stones, age-related macular degeneration, bone density, and cognitive function. Methods: A review of these articles reveals that each of these studies has compared the outcome of individuals at various levels of alcohol consumption with that of abstainers. Results: Each analysis has identified a U-shaped or J-shaped curve of reduced relative risk for a given disease state compared with abstainers. A clear definition of consumption in moderation becomes evident: for men it should not exceed 2 to 4 drinks per day, and for women it should not exceed 1 to 2 drinks per day. Conclusions: Alcohol by itself has favorable effects on the level of high-density lipoprotein cholesterol, and inhibition of platelet aggregation. Wine, particularly red wine, has high levels of phenolic compounds that favorably influence multiple biochemical systems, such as increased high-density lipoprotein cholesterol, antioxidant activity, decreased platelet aggregation and endothelial adhesion, suppression of cancer cell growth, and promotion of nitric oxide production.

How to control residual cardiovascular risk despite statin treatment: focusing on HDL-cholesterol.

Lowering low-density lipoprotein-cholesterol (LDL-C) is the primary target in the management of dyslipidemia in patients at high risk of cardiovascular disease. However, patients who have achieved LDL-C levels below the currently recommended targets may still experience cardiovascular events. This may result, in part, from elevated triglyceride (TG) levels and low levels of high-density lipoprotein-cholesterol (HDL-C). Low HDL-C and high TG levels are common and are recognized as independent risk factors for cardiovascular morbidity and mortality. Furthermore, atherogenic dyslipidemia, characterized by low levels of HDL-C, high TG, and small, dense LDL particles, is a typical phenotype of dyslipidemia in subjects with insulin resistance and metabolic syndrome. Therefore, to reduce further the risk of coronary heart disease (CHD), raising HDL-C and lowering TG may be the secondary therapeutic target for patients who achieve LDL-C levels below the currently recommended targets but are still at risk of CHD. However, whether increasing HDL-C levels alone reduces CHD has not yet been confirmed in large randomized clinical trials, and whether functional HDL is more important than HDL-C in reducing CHD remains controversial. Large CHD endpoint trials that include many patients with diabetes are underway to compare combination treatments with statin and niacin, fibrates, or cholesteryl ester transfer protein inhibitors with statin alone treatments. In this review, we discuss the rationale and importance of increasing HDL-C levels with and without lowering TG levels in the treatment and prevention of cardiovascular events.

Low drug levels and thrombotic complications in high‐risk atrial fibrillation patients treated with direct oral anticoagulants

Essentials Direct oral anticoagulants (DOACs) do not require laboratory monitoring currently. DOAC specific measurements were performed at trough in patients with atrial fibrillation. Patients who developed thromboembolic events showed lower DOAC plasma levels. This study supports the concept of measuring DOAC levels at steady state. SUMMARY Background Direct oral anticoagulants (DOACs) are administered at fixed doses without the need for dose adjustment according to laboratory testing. High interindividual variability in drug blood levels has been shown with all DOACs. To evaluate a possible relationship between DOAC C-trough anticoagulant levels and thromboembolic events, 565 consecutive naive patients with atrial fibrillation (AF) were enrolled in this study performed within the START Laboratory Registry. Methods DOAC-specific measurements (diluted thrombin time or anti-activated factor II calibrated for dabigatran; anti-activated FX calibrated for rivaroxaban or apixaban) at C-trough were performed locally at steady state within 15-25 days after the start of treatment. For each DOAC, the interval of C-trough levels, from the limit of quantification to the highest value, was subdivided into four equal classes, and results were attributed to these classes; the median values of results were also calculated. Thromboembolic complications occurring during 1 year of follow-up were recorded. Results Thromboembolic events (1.8%) occurred in 10 patients who had baseline C-trough levels in the lowest class of drug levels. The incidence of thromboembolic events among patients with DOAC C-trough levels in the lowest level class was 2.4%, and that in the remaining groups was 0%. The patients with thrombotic complications also had a higher mean CHA2 DS2 -VASc score than that of the total patient population: 5.3 (95% confidence interval [CI] 4.3-6.3 versus 3.0 (95% CI 2.9-3.1). Conclusion In this study cohort, thrombotic complications occurred only in DOAC-treated AF patients who had very low C-trough levels, with a relatively high CHA2 DS2 -VASc score. Larger studies are warranted to confirm these preliminary observations.

Effect of lipid restriction on mitochondrial free radical production and oxidative DNA damage.

Many studies have shown that caloric restriction (40%) decreases mitochondrial reactive oxygen species (ROS) generation in rodents. Moreover, we have recently found that 7 weeks of 40% protein restriction without strong caloric restriction also decreases ROS production in rat liver. This is interesting since it has been reported that protein restriction can also extend longevity in rodents. In the present study we have investigated the possible role of dietary lipids in the effects of caloric restriction on mitochondrial oxidative stress. Using semipurified diets, the ingestion of lipids in male Wistar rats was decreased by 40% below controls, while the other dietary components were ingested at exactly the same level as in animals fed ad libitum. After 7 weeks of treatment the liver mitochondria of lipid-restricted animals showed significant increases in oxygen consumption with complex I-linked substrates (pyruvate/malate and glutamate/malate). Neither mitochondrial H(2)O(2) production nor oxidative damage to mitochondrial or nuclear DNA was modified in lipid-restricted animals. Oxidative damage to mitochondrial DNA was one order of magnitude higher than that of nuclear DNA in both dietary groups. These results deny a role for lipids and reinforce the possible role of dietary proteins as being responsible for the decrease in mitochondrial ROS production and DNA damage in caloric restriction.

Prevalence of the Metabolic Syndrome Among Us Adults: Findings From the Third National Health and Nutrition Examination Survey

Metabolic syndrome is diagnosed when three or more of the following criteria are met: abdominal obesity (waist circumference more than 102 cm in men and 88 cm in women); hypertriglyceridemia of 150 mg/dl or above; a high-density lipoprotein (HDL) cholesterol level less than 40 mg/dl in men or 50 mg/dl in women; blood pressure of 130/85 mm Hg or higher; or fasting glucose of at least 110 mg/dl. Individuals with metabolic syndrome are likelier than others to develop diabetes and cardiovascular disease and have increased mortality from all causes (and from cardiovascular disease in particular). The investigators attempted to determine the prevalence of the syndrome in the United States by analyzing data on 8814 men and women 20 years of age or older who took part in the Third National Health and Nutrition Examination Survey in the years 1988 to 1994. This is a cross-sectional health survey of a sample of the noninstitutionalized civilian American population. The overall age-adjusted prevalence of metabolic syndrome was 23.7%. The prevalence rose from 6.7% in persons 20 to 29 years of age to 42% in those aged 70 years and more. There was virtually no gender-related difference in prevalence rates for the combined racial groups. Metabolic syndrome was most prevalent in Mexican Americans and least prevalent in whites, African Americans, and "others. " Among both African Americans and Mexican Americans, women had higher prevalence rates than men. Extrapolating from age-specific prevalence rates and US census counts from the year 2000, 47 million US residents have metabolic syndrome. Considering its prevalence, it seems important to estimate the direct medical costs of metabolic syndrome. In the great majority of cases the critical causes are improper nutrition and insufficient physical activity, emphasizing the importance of controlling obesity and encouraging physical activity in the United States.

Emerging role of bisphosphonates in the clinic--antitumor activity and prevention of metastasis to bone.

Bisphosphonates are currently used for the treatment of bone metastases, and emerging data suggest that they may also have antitumor properties. Preclinical studies have demonstrated that zoledronic acid can inhibit angiogenesis, invasion and adhesion of tumor cells, and overall tumor progression, and emerging evidence suggests that the use of these agents may impede the development of skeletal metastases. In a recent clinical study in patients with metastatic bone disease, basal levels of vascular endothelial growth factor, a factor essential for angiogenesis, were significantly reduced in patients receiving zoledronic acid, suggesting that zoledronic acid may have clinically relevant antiangiogenic properties. Early clinical data on prevention of bone metastases by the early-generation bisphosphonate clodronate have yielded promising results in patients with breast cancer, and trials are currently ongoing to assess the efficacy of clodronate in this setting. Similarly, the new-generation bisphosphonate zoledronic acid has demonstrated activity in the prevention of bone metastases in small, 18-month pilot studies in patients with high-risk solid tumors (N=40; P=0.0002). Similarly, in a separate 5-year trial, the overall survival of patients with multiple myeloma was greater in patients whose standard treatment regimens included zoledronic acid compared with standard treatment alone (P<0.01). These encouraging early clinical results supported the initiation of larger randomized trials that are currently ongoing.

Hemoglobin concentration in white, black, and Oriental children: is there a need for separate criteria in screening for anemia?

The concentration of hemoglobin in blacks was found to be 0.5 to 1.0 g/dl lower than that of income-matched whites in several large surveys. This difference could be a racial characteristic of blacks, or it might be due to a higher frequency of genetic traits such as thalassemia minor and hemoglobinopathies, or to environmental factors such as iron deficiency. To help in making this distinction, we analyzed the data from multiphasic examinations (1973 to 1975) on 1718 white, 741 black, and 315 Oriental healthy, nonindigent children between 5 and 14 years of age. In the entire population, the median hemoglobin concentration averaged 0.5 g/dl lower in blacks than in whites of both sexes (t test, P less than 0.001). The differences still averaged 0.5 g/dl (P less than 0.001) after exclusion of all those with abnormal hemoglobin by electrophoresis (Hgb S and C) and those whose mean corpuscular volume was more than 5% below the normal mean for age (to exclude iron deficiency or thalassemia minor). The data strengthen the impression that blacks normally have a concentration of hemoglobin averaging about 0.5 g/dl less than in whites. If this is the case, about 10% of normal blacks will be mistakenly designated anemic, if the same norms are applied.

Prepregnancy BMI and the risk of gestational diabetes: a systematic review of the literature with meta-analysis.

The objective of this study is to assess and quantify the risk for gestational diabetes mellitus (GDM) according to prepregnancy maternal body mass index (BMI). The design is a systematic review of observational studies published in the last 30 years. Four electronic databases were searched for publications (1977-2007). BMI was elected as the only measure of obesity, and all diagnostic criteria for GDM were accepted. Studies with selective screening for GDM were excluded. There were no language restrictions. The methodological quality of primary studies was assessed. Some 1745 citations were screened, and 70 studies (two unpublished) involving 671 945 women were included (59 cohorts and 11 case-controls). Most studies were of high or medium quality. Compared with women with a normal BMI, the unadjusted pooled odds ratio (OR) of an underweight woman developing GDM was 0.75 (95% confidence interval [CI] 0.69 to 0.82). The OR for overweight, moderately obese and morbidly obese women were 1.97 (95% CI 1.77 to 2.19), 3.01 (95% CI 2.34 to 3.87) and 5.55 (95% CI 4.27 to 7.21) respectively. For every 1 kg m(-2) increase in BMI, the prevalence of GDM increased by 0.92% (95% CI 0.73 to 1.10). The risk of GDM is positively associated with prepregnancy BMI. This information is important when counselling women planning a pregnancy.

Pooled analysis of prospective cohort studies on height, weight, and breast cancer risk.

The association between anthropometric indices and the risk of breast cancer was analyzed using pooled data from seven prospective cohort studies. Together, these cohorts comprise 337,819 women and 4,385 incident invasive breast cancer cases. In multivariate analyses controlling for reproductive, dietary, and other risk factors, the pooled relative risk (RR) of breast cancer per height increment of 5 cm was 1.02 (95% confidence interval (CI): 0.96, 1.10) in premenopausal women and 1.07 (95% CI: 1.03, 1.12) in postmenopausal women. Body mass index (BMI) showed significant inverse and positive associations with breast cancer among pre- and postmenopausal women, respectively; these associations were nonlinear. Compared with premenopausal women with a BMI of less than 21 kg/m2, women with a BMI exceeding 31 kg/m2 had an RR of 0.54 (95% CI: 0.34, 0.85). In postmenopausal women, the RRs did not increase further when BMI exceeded 28 kg/m2; the RR for these women was 1.26 (95% CI: 1.09, 1.46). The authors found little evidence for interaction with other breast cancer risk factors. Their data indicate that height is an independent risk factor for postmenopausal breast cancer; in premenopausal women, this relation is less clear. The association between BMI and breast cancer varies by menopausal status. Weight control may reduce the risk among postmenopausal women.