***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Recently , we demonstrated that the large pool of folate present in the colon of humans can be absorbed . Here , we investigated whether the net amount of folate synthesized by bacteria in the colon of piglets can be modified by feeding prebiotics to alter their microbial milieu . Male piglets ( age 5 d , n = 12 ) were r and omized to a milk-based formula containing either 5 g/L inulin + 5 g/L galactooligosaccharides ( IN-GOS ) or 5 g/L maltodextrin ( control ) .  Body weight did not differ between groups during the 28-d feeding intervention . However , the mean weight of colonic tissue ( 38 % ) and their contents ( 238 % ) was higher in the IN-GOS than in the control group ( P = 0.004 , P = 0.0001 , respectively ) . Total bacterial load in the colon of piglets fed IN-GOS was 531 % greater and the total amount of folate found in the colon contents was 53 % greater than that of controls ( P = 0.002 , P = 0.02 , respectively ) . Indices of blood folate status ( plasma and RBC folate and plasma homocysteine ) and folate concentrations in liver and kidneys were unaffected . Both groups exhibited low RBC folate ( 56 ± 23 nmol/L ) and elevated homocysteine ( 24 ± 7 μmol/L ) concentrations , evidence of deficiency if present in humans . In conclusion , dietary supplementation with 5 g of inulin + 5 g of galactooligosaccharides increased the weight , bacterial load , and total folate content in the piglet colon ; however , these changes were insufficient to modify indices of whole body folate status . Future studies investigating the impact of feeding prebiotics on localized folate status at the level of the colonocyte are warranted Creatinine degradation was prospect ively studied in four healthy subjects and 35 patients with varying degrees of chronic renal failure by measuring creatininase activity in stool isolates . Patients were subdivided into those with serum creatinine above and below 6 mg/dL.  Creatinine degradation in the former group of patients who had not taken antibiotics in the previous 3 months was significantly greater than the latter ( 64 % v 26 % ; P < 0.001 ) , which was similar to healthy controls . This degradation was abolished when antibiotics were added directly to the patient 's stool during incubation ( P < 0.002 ) . In a subset of five patients , duodenal intubation demonstrated small bowel bacterial overgrowth associated with high concentrations of toxic methylamines generated there from and increased stool creatinine consumption . We conclude that retained creatinine in advanced chronic renal failure induces bacterial creatininase activity throughout the bowel , causing creatinine degradation and subsequent potential loss of creatinine to the creatinine pool . The modifying effects of antibiotics on creatinine degradation has important clinical implication s for the interpretation of serum creatinine measurements in renal failure In chronic renal failure ( CRF ) , plasma concentrations of the products of protein metabolism are increased . Current dietary management is to prescribe a decrease in protein intake . The use of dietary fiber to increase fecal excretion of retained metabolites in CRF may be a beneficial adjunct to a low-protein diet ( LPD ) . Colonic bacteria ferment dietary fiber , providing them with energy for growth and nitrogen incorporation , in turn , increasing nitrogen excretion in feces . Sixteen CRF patients consuming an LPD were r and omly assigned to receive a supplement of a highly fermentable fiber , gum arabic ( 50 g/d ) , or a placebo ( 1 g pectin/d ) in a prospect i ve , single-blind , crossover design . Fecal bacterial mass and fecal nitrogen content were significantly increased during supplementation with gum arabic compared with the baseline LPD or supplementation with pectin . Serum urea nitrogen was significantly decreased during supplementation with gum arabic compared with the baseline LPD or supplementation with pectin . Nitrogen balance did not change significantly BACKGROUND The US Food and Drug Administration ( FDA ) approved health cl aims for 2 dietary fibers , beta-glucan ( 0.75 g/serving ) and psyllium ( 1.78 g/serving ) , on the assumption that 4 servings/d would reduce cardiovascular disease risk . OBJECTIVE We assessed the efficacy of this dose of fibers in reducing serum lipid risk factors for cardiovascular disease . DESIGN Sixty-eight hyperlipidemic adults consumed a test ( high-fiber ) and a control low-fat ( 25 % of energy ) , low-cholesterol ( < 150 mg/d ) diet for 1 mo each in a r and omized crossover study . The high-fiber diet included 4 servings/d of foods containing beta-glucan or psyllium that delivered 8 g/d more soluble fiber than did similar , unsupplemented foods in the control diet .  Fasting blood sample s and blood pressure readings were obtained at baseline and weeks 2 and 4 , and the subjects ' weight was monitored weekly . RESULTS Compared with the control diet , the high-fiber diet reduced total cholesterol ( 2.1 + /- 0.7 % ; P = 0.003 ) , total : HDL cholesterol ( 2.9 + /- 0.8 % ; P = 0.001 ) , LDL : HDL cholesterol ( 2.4 + /- 1.0 % ; P = 0.015 ) , and apolipoprotein B : A-I ( 1.4 + /- 0.8 % ; P = 0.076 ) . Applying the Framingham cardiovascular disease risk equation to the data confirmed a reduction in risk of 4.2 + /- 1.4 % ( P = 0.003 ) . Small reductions in blood pressure were found after both diets . The subjects reported no significant differences in palatability or gastrointestinal symptoms between the diets . CONCLUSIONS The reduction in serum lipid risk factors for cardiovascular disease supports the FDA 's approval of a health cl aim for a dietary fiber intake of 4 servings/d . Although relatively small in terms of patient treatment , the reduction in cardiovascular disease risk is likely to be significant on a population basis INTRODUCTION Protein-bound uraemic retention solutes , including p-cresyl sulfate and indoxyl sulfate , contribute substantially to the uraemic syndrome . These and several other uraemic retention solutes originate from intestinal bacterial protein fermentation . We investigated whether the prebiotic oligofructose-enriched inulin reduced serum concentration of p-cresyl sulfate and indoxyl sulfate , through interference with intestinal generation . METHODS We performed a single centre , non-r and omized , open-label phase I/II study in maintenance HD patients with a 4-week , escalating dose regimen of oligofructose-enriched inulin ( ORAFTI Synergy 1 , Tienen , Belgium ) ( www . clinical trials.gov NCT00695513 ) . Changes in p-cresyl sulfate and indoxyl sulfate serum concentrations as well as changes in p-cresyl sulfate and indoxyl sulfate generation rates were analysed . RESULTS Compliance with therapy was excellent . p-Cresyl sulfate serum concentrations at 4 weeks were significantly reduced by 20 % ( intention to treat , P = 0.01 ; per protocol , P = 0.03 ) . Also p-cresyl sulfate generation rates were reduced ( P = 0.007 ) . In contrast , neither indoxyl sulfate generation rates ( P = 0.9 ) nor serum concentrations ( P = 0.4 ) were significantly changed . CONCLUSION The prebiotic oligofructose-inulin significantly reduced p-cresyl sulfate generation rates and serum concentrations in haemodialysis patients . Whether reduction of p-cresyl sulfate serum concentrations , an independent predictor of cardiovascular disease in HD patients , will result in improved cardiovascular outcomes remains to be proven OBJECTIVES This study was design ed to examine the hypothesis that higher intake of dietary fiber is inversely related to the  risk of cardiovascular disease ( CVD ) and myocardial infa rct ion ( MI ) in a large prospect i ve cohort of women . BACKGROUND Although dietary fiber has been suggested to reduce the risk of coronary disease , few prospect i ve studies have examined the association between the types and amounts of dietary fiber and CVD risk , particularly among women . METHODS In 1993 , we used a semi-quantitative food frequency question naire to assess dietary fiber intake among 39,876 female health professionals with no previous history of CVD or cancer . Women were subsequently followed for an average of six years for incidence of nonfatal MI , stroke , percutaneous transluminal coronary angioplasty , coronary artery bypass graft or death due to CVD confirmed by medical records or death certificates . RESULTS During 230,006 person-years of follow-up , 570 incident cases of CVD were documented , including 177 MIs . After adjustment for age and r and omized treatment status , a significant inverse association was observed between dietary fiber intake and CVD risk . Comparing the highest quintile of fiber intake ( median : 26.3 g/day ) with the lowest quintile ( median : 12.5 g/day ) , the relative risks ( RR ) were 0.65 ( 95 % confidence interval [ CI ] : 0.51 , 0.84 ) for total CVD and 0.46 ( 95 % CI : 0.30 , 0.72 ) for MI . Additional adjustment for CVD risk factors reduced the RRs to 0.79 ( 95 % CI : 0.58 , 1.09 ) for total CVD and 0.68 ( 95 % CI : 0.36 , 1.22 ) for MI . The inverse trends across categories generally remained , although they were no longer statistically significant . Inverse relations were observed between both soluble and insoluble fiber and risk of CVD and MI , and among those who had never smoked and those with body mass index < 25 . CONCLUSIONS A higher intake of  dietary fiber was associated with a lower risk of CVD and MI , although the association was not statistically significant after further adjusting for multiple confounding factors . Nevertheless , these prospect i ve data generally support current dietary recommendations to increase the consumption of fiber-rich whole grains and fruits and vegetables as a primary preventive measure against CVD BACKGROUND Considerable attention has been given to the impact of nutrition on kidney disease . Most dietary attempts to treat chronic renal failure ( CRF ) and to decrease uremia use a protein restriction . An alternative dietetic approach based on fermentable carbohydrate ( FC ) supplementation of the diet could lead to the same urea-lowering effect by increasing urea nitrogen ( N ) excretion in stool , with a concomitant decrease of the total N quantity excreted in urine . METHODS In the present prospect i ve study , the impact of FC ( 40 g/d ) on uremia and on N excretion routes was investigated during 5 weeks in nine CRF patients in the presence of a moderated restrictive protein diet ( 0.8 g/kg/d ) . Patients were their own controls and were treated by the cross-over method after r and omization ( 5 weeks with FC versus 5 weeks without FC ) . RESULTS Feeding FC significantly increased the quantity of N excreted in stool from 2.1 + /- 0.8 to 3.2 + /- 1.1 g/d ( + 51 % ) ( P < .01 ) and decreased , in parallel , the urinary N excretion from 9.4 + /- 1.7 to 8.3 + /- 1.4 g/d ( -12 % ) ( P < .01 ) . The total N quantities excreted by the two routes were unchanged by the FC , which shows that the FC was efficient to shift N excretion from the urinary route toward the digestive route . As a result of the increase of urea transfer into the colon , the plasma urea concentration was significantly decreased from 26.1 + /- 8.7 to 20.2 + /- 8.2 mmol/L ( -23 % ) ( P < .05 ) . CONCLUSIONS These results show the same beneficial effects in CRF as those obtained with a restrictive protein diet without its nutritional drawbacks . This should be confirmed by other prospect i ve works over a longer duration and a larger number of patients to study the effects of FC on CRF progression and on CRF terminal stage tolerance Activation of intestinal Na+–glucose cotransport increases paracellular movement of inert tracers in cultured monolayers , isolated rodent intestinal mucosae , and in rodents in vivo . However , not all studies have demonstrated comparable effects on human intestinal paracellular absorption . We sought to assess the effects of Na+–glucose cotransport on paracellular absorption in human beings using a simple noninvasive assay . Study subjects drank six 200-ml doses of test solution , composed of 0.8 % w/v creatinine ( sufficient to overwhelm endogenous creatinine ) in 277 mM glucose or mannitol and urine was collected . Intestinal 
    Output:
    
Conclusions : This is the first study to summarize the potential beneficial effects of dietary fiber in the CKD population demonstrating a reduction in serum urea and creatinine , as well as highlighting the lack of clinical trials on harder end points .