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3895388
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The sampling process preceding a clinical trial is associated with numerous fallacies. This is especially true in non-ulcer dyspepsia, which is a prevalent but poorly defined condition, probably with heterogenic etiologies. Therefore, in order to make subsequent inferences possible, it is crucial that rigorous criteria for adherence to the target population--and the studied sample--are established in advance. Several factors, however, preclude a strictly random sample from the target population. Firstly, only those who find their way to medical services are included in trials, and different circumstances may affect the patient's decision to seek medical advice. Secondly, the doctor's decision to refer a patient to a study is influenced by a number of factors that might introduce bias. As an example, an on-going study of non-ulcer dyspepsia is presented. With the application of strict symptomatic criteria, and the exclusion of circumscribed organic lesions of the upper gastrointestinal tract by means of endoscopy, it was possible to define a population in which very few additional pathological findings were made at thorough diagnostic work-up.
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3895389
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In spite of the fact that both laymen and clinicians have pointed out their relevance, the psychological aspects of gastrointestinal disorders, especially their influence on etiology and pathophysiology, have been a matter of controversy and challenge to researchers. Difficulties in this field arise from several sources, for instance, the sampling methodology in the selection of patients and the heterogeneity of the disorders studied. When the irritable bowel syndrome (IBS) is compared with peptic ulcer disease (PUD), the personality features of IBS have not been described with the same consistency as the dependency traits of PUD. Also, IBS patients have been regarded as more neurotic and depressed than PUD patients. In this study of 101 IBS and 103 PUD patients, our overall impression was that mental symptoms and personality profiles were essentially the same in IBS and PUD, but that both groups differed from a normal population. We conclude that from a psychosomatic point of view IBS and PUD may be looked upon as different facets of the same underlying psychogenic mechanism. Although conclusive evidence of how psychological factors affect physiological processes and contribute to the clinical picture in gastrointestinal disorders is still lacking, it seems reasonable to state that they are often significant and must be considered in treating individual IBS and PUD patients.
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3895390
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The specialised regions of the stomach include the cardia, fundus, body, antrum and the pylorus. Not only do these regions have specific secretory functions, but also, they have specific motor functions as well. For example, the proximal stomach is most important in regulating emptying of liquids and the distal stomach and pylorus, the emptying of solids. Disorders of gastric emptying can be classified into two major categories: mechanical obstruction due to increased resistance and functional obstruction (gastroparesis) due to pump failure. Gastroparesis is best diagnosed using a solid test meal which is labelled by a gamma-emitting radionuclide. Agents employed to treat gastroparesis include bethanechol, metoclopramide and domperidone. Entero-gastric reflux occurs when there are abnormalities in the duodeno-gastric pressure gradient or the duodeno-gastric resistance mechanism. Excessive entero-gastric reflux may be seen in patients with gastric ulcers, chronic obstructive pulmonary disease, post-cholecystectomy syndrome or post-operative entero-gastric reflux gastritis. The diagnosis of entero-gastric reflux gastritis depends upon typical symptoms and the demonstration of excessive entero-gastric reflux by scintigraphic techniques or the measurement of bile concentrations within the stomach. Medical treatment with bile chelating agents and surface coating agents has been disappointing. Surgical treatment should only be undertaken as a last resort.
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3895391
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A simple method for grading gastritis is to assess the severity of round cell infiltration and the loss of normal glands, and this may be applied to both antral and body changes. However, there is, as yet, no satisfactory classification of gastritis. In population samples, gastritis shows a linear increase in age-specific prevalence so that the annual increase in the body atrophic gastritis pool up to geriatric age is constant (1.5%). In the elderly, there appears to be a retardation of the process, particularly in the antral mucosa, where some healing trend is demonstrable. This dynamic behaviour is qualitatively similar in all population samples collected in Finland and Estonia. On the other hand, the dynamic behaviour of gastritis in different subpopulations differs markedly from that in the population at large. In pernicious anemia patients and their first-degree relatives, the progression of body atrophic gastritis in its final stages is about 20 times more rapid than in a general population, while, simultaneously, antral gastritis displays a distinct healing tendency. A behaviour opposite to that in pernicious anemia is seen in patients with active or healed duodenal ulcer disease and in duodenitis: antral gastritis behaves, on the whole, similarly to that in the general population, but in the body mucosa there occurs virtually no progression with age, and the mucosa generally remains normal or at the stage of superficial gastritis. However, after antrectomy body gastritis progresses rapidly in the remnant at first, but it slows down later and then closely resembles that in the general population.(ABSTRACT TRUNCATED AT 250 WORDS)
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3895392
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"Duodenitis" remains a controversial area in clinical medicine. This review discusses the various methods of diagnosis (histology, radiology, endoscopy) and concludes that "endoscopic duodenitis" is a definite clinical entity. Studies are presented on the changes in duodenitis in relation to peptic ulcer disease, and it is concluded that "endoscopic duodenitis" is unlikely to be the cause of symptoms unless accompanied by a peptic ulcer.
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3895393
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Gastric mucosa has a particular ability to resist acid/peptic digestion. The nature of the presumed barrier to acid and pepsin has been elusive but recent work suggests that a combination of mechanisms is likely to be involved. Amongst these the mucus gel layer combined with secretion of alkali by the surface epithelium is likely to form a first line defence. The demonstration of a pH gradient within the mucus gel layer supports such a hypothesis. Agents which damage the mucosa such as aspirin and bile salts inhibit the maintenance of the pH gradient allowing the luminal surface of the epithelium to become more acid. Prostaglandins enhance this pH gradient, an observation which may be relevant to the protective properties of prostaglandins. This alkaline zone can be compromised by high levels of luminal acidity and it thus has a limited capacity to prevent acid reaching the mucosa. The local microcirculation is of importance in maintaining surface epithelial metabolic integrity and interstitial fluid bicarbonate may be important in neutralising any acid which may reach the subepithelial layers. This may in part explain the ability of an actively secreting gastric epithelium to resist damage to a greater extent than a resting mucosa. Recent exciting work has focussed on the ability of gastric epithelium to reform by a process which has been termed restitution, after acute mucosal damage. This process appears to be rapid and occurs within an hour or so. Repeated rapid repair may be a common occurrence in the maintenance of mucosal integrity. Finally, it has been proposed that a hydrophobic property of surface epithelium in the stomach may be relevant to mucosal protection.
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3895394
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Like other nucleated cell populations in the body, the cells of the gastroduodenal mucosa are capable to metabolise arachidonic acid into prostaglandins, with prostaglandin E2 as the probable major metabolite. The production increases on demand and can be followed in the gastric lumen, where the output of prostaglandin E2 increases two to fourfold after exposure of the mucosa to hydrochloric acid. Exogenous prostaglandins, in particular of the E series, stimulate several identified mucosal defense factors in the upper gastrointestinal tract. Prostaglandins of the E series stimulate the transport of bicarbonate and the production and release of mucus glycoproteins from the gastroduodenal mucosa. They have trophic effects on gastrointestinal epithelia by increasing the survival time of mucosal cells and have cytoprotective properties. In addition, E2 prostaglandins suppress the gastric acid secretion and accelerate peptic ulcer healing. Non steroidal antiinflammatory drugs, which block the biosynthesis of prostaglandins, suppress the bicarbonate secretion, the production of mucus glycoproteins and cytoprotective properties. They interfere with the inhibitory feedback regulation of the gastric acid secretion and are ulcerogenic in experimental and clinical situations. These actions of PG biosynthesis blockers provide indirect information on the importance of local prostaglandin formation for maintenance of gastrointestinal mucosal integrity. It is hypothesised that biosynthesis of prostaglandins in the gastroduodenal mucosa is of importance and may be a key event in triggering the different components of the mucosal defense.
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3895395
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Polyclonal anti-idiotypic antibodies against monoclonal antibodies with specificity for RT1-encoded antigens were induced in syngeneic, allogeneic, and xenogeneic hosts. The immune response to the idiotypic determinants on monoclonal antibodies was T-cell-dependent. The anti-idiotypic antibodies, independent of whether they were induced in syngeneic, allogeneic, or xenogeneic (after proper absorption) hosts, showed an exquisite specificity for the monoclonal antibody used for the induction. No cross-reactivity with other monoclonal antibodies could be observed.
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3895396
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A double-antibody biotin-avidin enzyme-linked immunosorbent assay (ELISA) for quantification of the C3d split products is described. Polyethylene glycol 6000 was used to precipitate large C3 molecules, and the C3d-containing supernatant was used in the assay. C3d was measured in ethylenediaminetetraacetic acid plasma from 40 healthy blood donors, and the normal range was defined. Twenty-two patients were tested, and 12 of these had increased levels of C3d. No correlation was observed between total C3 and C3d in these patients. There was a close correlation between C3d measured by this method and by the double-decker rocket immunoelectrophoresis method. The C3d ELISA method is very sensitive, easy to perform, and time-saving and economical compared with most C3d methods already described. A procedure to define the lower detection limit and examine the reliability of an ELISA method in general is discussed.
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3895397
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The active metabolite of vitamin D3, 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3), was tested for the ability to differentiate promyelocytic leukaemia cells (HL-60) and histiocytic lymphoma cells (U937) into cytotoxic effector cells against K562 leukaemia cells. A concentration of 10(-6) M 1,25(OH)2D3 differentiated HL-60 cells into substrate-adherent monocyte-like cells with cytolytic activity against antibody-coated K562 cells. These differentiated HL-60 cells were not able to lyse uncoated K562 cells in an 18-h Cr-release assay. Similar treatment of the U937 cells with 1,25(OH)2D3 did not make them cytolytic towards K562 cells. These data indicate that 1,25(OH)2D3 can differentiate HL-60 cells to mature monocytes with cytolytic activity against antibody-coated leukaemia cells.
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3895399
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The antibody response to the rabies human diploid cell strain vaccine was compared after pre-exposure immunization with 0.1 ml intradermal (i.d.) and 1.0 ml subcutaneous (s.c.) vaccination. After primary immunization, 2 doses of vaccine 1 month apart, all vaccinees in the two groups had antibody titers detectable by ELISA. However, the mean antibody titer after the 0.1 ml i.d. doses (5.9 EU/ml) was half of what was obtained after the 1.0 ml s.c. doses (12.2 EU/ml). Likewise, though all vaccinees responded on the 1-year booster dose the mean antibody level after i.d. vaccination (8 EU/ml) was 2.5 times lower than after 1.0 ml s.c. dose (21.5 EU/ml). At 1 year 70% of the vaccinees had detectable antibody levels irrespective of vaccination route. A few individuals responded to one of their i.d. doses with only minor titer rises which is supposed to be due to inadvertent s.c. injection of the i.d. dose.
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3895398
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Concanavalin-A-activated T cells and their crude supernatants were assayed for suppressive activity on an IgE-producing U-266 cell line. Detectable and comparable degrees of suppression were obtained with the co-culture and the supernatant protocols. Separation of the effector population into T4+ and T8+ subsets showed the most effective cells in the T8+ fraction. Control experiments demonstrated that the IgE down-regulation was selective, since parallel measurement of beta 2-microglobulin synthesis showed no effect of T cells or T-cell-derived supernatants. In addition, several human T-cell lymphoma-leukaemia virus I-transformed T-cell lines were explored for their capacity to produce factor(s) able to suppress IgE synthesis in the U-266 cell line, and four out of 25 cell lines could be shown to do this in a constitutive manner. Kinetic studies suggested that the inhibition occurred at a transcriptional level. The results indicate that the T-cell-myeloma system is an interesting model to define better the regulation of IgE in the human.
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3895401
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The relationship between significant bacteriuria (SB), i.e. 2 subsequent voided urine specimens with greater than or equal to 10(5) colony forming units (CFU)/ml, and the occurrence of bacteria in the urinary bladder detected by bladder punction, was investigated in asymptomatic pregnant women. From 30 (70%) of the 43 women with SB studied, bacteria were isolated from the urinary bladder. The same bacteria were found in the bladders of all 21 women with Escherichia coli, the one with Klebsiella pneumoniae, and the one with Staphylococcus saprophyticus in midstream urine. Six of 10 patients with group B streptococci (GBS), 1 of 4 patients with Streptococcus faecalis, and none of 5 patients with Staphylococcus epidermidis in voided specimens had bacteria in the aspirated urine. Serotype III was isolated from 8/10 patients with SB caused by GBS. One child born to a woman with GBS SB but no bacteria in the urinary bladder, got early onset septicaemia. The poor predictive value of SB with GBS, S. faecalis and S. epidermidis necessitates the increased use of bladder puncture for diagnosis of true asymptomatic bacteriuria (AB), i.e. AB with bacteria in the urinary bladder. SB with GBS even without bacteria in the urinary bladder, may constitute a threat to the baby's health.
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3895402
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The antibacterial interaction of methenamine hippurate (MH) and trimethoprim (TMP) was tested in vitro in 3 different media: urine, brain-heart broth and Mueller-Hinton broth. MH and TMP were found to have a synergistic interaction in chequer-board titration against 11/11 bacteria in urine. Low concentrations of MH (1/2 MIC) had an additive or synergistic effect with TMP against 14/14 bacteria in brain-heart broth and 20/26 bacteria in Mueller-Hinton broth. In addition, the growth of bacteria in urine from healthy subjects treated with TMP (200 mg), MH (1000 mg) or a combination of TMP + MH (200 + 1000 mg) twice a day for 5 days was compared. A synergistic or additive effect of TMP and MH was found against 14/16 strains. Antagonistic interaction was not found in any of the tests. Preliminary pharmacokinetic studies with TMP and MH showed no marked interaction between the drugs. The hydrolysis of MH to formaldehyde was inversely related to urinary pH, and at pH 5 most of the formaldehyde released from MH in urine was generated within 3 h. The results suggest that the combination of TMP and MH may be more efficient than TMP alone in the treatment of urinary tract infections.
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3895400
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64 clinical isolates of group B streptococci from cerebrospinal fluids of neonates were tested for susceptibility to 6 antibiotics. The strains were obtained in The Netherlands during 7 years. The usefulness of the generally recommended initial therapy, a combination of ampicillin and gentamicin, is supported.
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3895403
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The penetration of ceftazidime into the aqueous humour and the vitreous body of the rabbit eye, after intravenous (i.v.) bolus or subconjunctival injection, was investigated. A dose of 50 mg/kg body weight was administered. After i.v. administration the mean penetration into the aqueous humour was 13% of the plasma values. After subconjunctival injection into the left eye, mean levels of 14% and 25% of the plasma concentrations were found in the right and left eye, respectively. The concentrations in the vitreous body were in all cases below the ceftazidime detection limit (1 mg/l), i.e. less than 1% of the plasma levels. The mean penetration of ceftazidime into human aqueous humour (measured during cataract extraction) was 19% after 2 g i.v. bolus injection. Ceftazidime levels sufficient to inhibit the growth of most pathogens commonly responsible for intraocular infections, including Pseudomonas spp., were consistently found in the aqueous humour. However, inadequate concentrations were achieved in the vitreous body.
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3895404
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Shaved trunk skin folds of hairy mice were scalded for 20 s by water immersion. In one set of experiments the effect of increasing burn temperature (51 degrees C-60 degrees C) was studied, in another the folds were first scalded at 51 degrees C-54 degrees C and then immediately cooled for 30 min in 8 degrees C water. Animals were killed 2 h and 4 days postburn. Before sacrifice, Evans blue was injected i.v. to some animals to visualize preserved vascular perfusion and areas of increased permeability. Macroscopic observations (and photographic documentation) were made of the outside and inside of the injured skin and biopsies for light microscopy were obtained centrally in the burns. The injured area was measured by planimetry on photographs and expressed in percent of the whole burned area. At 4 days, brownish, oval areas appeared on the skin being progressively larger with increasing burn temperature. The 51 degrees C burn only resulted in a very small, spotlike, tissue injury, while the greater than or equal to 52 degrees C produced a macroscopic necrosis amounting to 40%-94% of the burned area. Postburn cooling did not reduce the damaged area as recorded 4 days postburn. Histologically, the tissues seemed well preserved at 2 h after 51 degrees C scalds, whereas cell damage was obvious and increasingly pronounced after greater than or equal to 53 degrees C burns. After 52 degrees C burns a mixed picture emerged. A similar microscopic pattern was seen at 4 days; 51 degrees C specimens were undamaged, some 52 degrees C and all greater than or equal to 53 degrees C were necrotic.(ABSTRACT TRUNCATED AT 250 WORDS)
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3895405
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A prospective double blind study using Varidase or Trypure on 2nd degree local burns in 18 patients was performed. No difference in cleaning or healing effect was revealed. In 6 out of 11 Trypure-treated and 1 out of 12 Varidase-treated patients treatment had to be discontinued because of intolerable pain. This difference was statistically significant.
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3895406
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On the basis of 37 surgically treated patients with hemifacial microsomia, an anatomical-surgical classification was developed which divides these patients into five categories to facilitate surgical planning and help standardize treatment. Treatment was founded on the cooperation of a large craniofacial team. Osteotomies of the jaws, construction of the TM joint with costochondral grafts, onlay bone grafts, and genioplasty were performed to improve facial form and function. Facial scars were avoided. After three-dimensional skeletal alignment, there was rarely a compelling need for subsequent soft tissue augmentation.
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3895407
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In the recent past, the latissimus dorsi musculocutaneous flap has added a significant tool to the armamentarium of the reconstructive surgeon. The history of its clinical use is reviewed with emphasis on embryological, anatomical and hemodynamic aspects.
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3895408
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A series of 24 consecutive patients with osteomyelitis of the tibia and soft tissue defects were treated according to the principle of radical excision of the infected bone together with transposition of muscle flaps and primary skin cover as a one-stage procedure. External fixation was used for stabilization of bone. The mean duration of osteomyelitis before radical operation was 72 weeks and the previous stay in hospital averaged 15 weeks. Twenty-one patients had previously undergone 3.7 operations because of the infection. Staphylococcus aureus was cultured in 50% of the patients, while no bacteria could be identified in six patients. Appropriate antibiotics were given for an average of eight weeks. In four patients a secondary bone transplant and in three patients another skin transplant was necessary. One patient refusing further reconstructive surgery insisted on an above-knee amputation because of persisting infection. After an average observation time of 2 1/2 years no infection or instability of the tibia could be demonstrated, but one patient showed two small skin defects. These results indicate that radical excision of infected bone in combination with muscle transposition and primary skin cover is effective in the treatment of posttraumatic osteomyelitis of the tibia.
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3895410
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Eighteen women (median age 54 years, 36-79) with urinary motor urge (n = 13) or sensory urge (n = 5) incontinence were treated for three 2-week periods with emepronium carrageenate (EC) (Cetiprin Novum) in daily doses of 500 and 1000 mg and placebo. Subjectively the women experienced an increased ability to control micturition, i.e. less urge, during EC treatment. Only mild and mainly anticholinergic side effects were recorded, most frequently dryness of the mouth. As regards side effects, the evaluation of objective effects were complicated by a tendency towards carry-over effect to placebo. Placebo in the first treatment periods were analysed solely; no effects of placebo could be demonstrated. Compared with the reference period, decreases in the total number of micturitions (approx. 20%) and in the number of urge incontinence episodes (approx. 75%) were seen. As compared with placebo, a significant increase (approx. 25%) in the average micturition volume could be demonstrated. The percentage urinary excretion of emepronium decreased with increasing oral intake and with advancing age. Probably, an initial daily dosage of 500 mg EC will do well in younger women (less than 50 years), whereas elder patients may need 1000 mg. Further dosage recommendations are given.
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3895409
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In a single-blind, randomized trial, the efficacy of topical streptokinase-streptodornase (Varidase) solution was compared with that of zinc oxide on necrotic pressure ulcers in 28 patients. The effectiveness was determined by measuring the necrosis removal within 8 weeks. This occurred in 6 patients (43%) treated with Varidase and in 7 (50%) treated with zinc oxide. The statistical tests applied showed no significant difference between the two treatments despite the use of a high power (1-beta = 0.95). The data suggest that the two regimens are about equally effective in the treatment of necrotic tissue.
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3895411
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When constructing arteriovenous fistulas for haemodialysis in chronic renal failure patients, one of the main problems is still their clotting tendency. Ticlopidine is an effective inhibitor of platelet aggregation. In this randomized double-blind study placebo or ticlopidine 250 mg twice daily was given to chronic uremic patients up to 4 weeks after construction of an arteriovenous fistula. 42 patients were recruited and 36 completed the trial. The fistula clotted in 8 patients on placebo and in 2 patients on ticlopidine. The difference is significant. This effect was achieved without an increased frequency of side effects compared with placebo. It is concluded that ticlopidine has a function as a thromboprophylactic drug in chronic uremic patients.
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3895412
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Congenital malformations and physical disablement call not only for current definitions and classification, but also for radical discussion of our own mentality with regard to afflicted patients and their environment. A historical view may help clarify our opinions and positions.
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3895413
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Irrespective of the etiology, a water and electrolyte imbalance provoking a hypo- or hyperosmolar state causes metabolic encephalopathy, as may occur with any metabolic disturbance. The pathophysiology of metabolic encephalopathy relies on a diffuse neuronal dysfunction which occasionally shows a focal maximum. To the clinician it presents in the form of nonspecific symptoms or signs, such as altered level of alertness or awareness of the environment, or impaired attention, cognition or orientation. When the onset of hypo- or hyperosmolality is rapid, delirium may develop or the level of consciousness can decrease to the point of coma. Myoclonic jerks, gait disturbance and focal or generalized fits are additional nonspecific signs. When the water and electrolyte imbalance coincides with or is caused by brain disease, the signs of the two conditions are added. On the other hand, complicating hemorrhages, sinus thrombosis, or brainstem herniation or compression may be taken for a primary structural brain lesion, and the water and electrolyte imbalance may easily be overlooked. Pathophysiology, symptoms and signs, and therapy of hypo- and hyperosmolar states are discussed. Central pontine myelinolysis is considered separately.
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3895414
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Until the beginning of the 17th century it was assumed that the arteries carried a subtle kind of air or spirit to the organs, and the veins the nutrient blood. No one seems to have seriously considered that a backflow was necessary. The circulation of the blood was discovered in 1628 by William Harvey. Blood pressure was first measured in animals by Hales (1733). Reliable blood pressure measurements in humans were rendered possible at the beginning of the 20th century through the efforts of Mahomed, von Basch, Potain, Riva-Rocci and Korotkoff. In 1903 electrocardiography was introduced by Einthoven. In 1941 the use of venous catheterization by Cournand initiated the giant forward strides of modern cardiovascular research, diagnosis and therapy.
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3895423
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The incidence of pancreatic cancer, the incidence rate of physicians in a given area, the sensitivity and specificity of morphological (ERCP, CT, sonography), cytological and serological (CEA, alpha-fetoprotein, POA, R-nase, LAI, CA 19-9) examination methods were used (taking the cities of Ulm and Hannover as basis) for calculating that a general practitioner, or a practising internist, may be able to diagnose a case of pancreatic cancer about 3-4 times during his professional career, and at the most once only one early cancer. There is at present no screening method. Diagnosis of an early cancer entirely free from any symptoms, is a mere coincidence. When the first uncharacteristic complaints become manifest, the pancreatic cancer is already 3 to 5 years old; usually, it can then no longer be classified as an early cancer.
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3895425
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Groove pancreatitis is a special type of segmental pancreatitis. Its morphological aspects with participation of the peripheral dorsal and cranial parts of the pancreatic head, the pancreatic soft tissue, and the duodenal wall with frequent narrowing of the distal common bile duct and suprapapillar stenosis of the duodenum can be detected by means of sonography. If this type of seqmental pancreatitis is known, the suspicion of a carcinoma of the pancreatic head can be removed.
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3895426
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To examine possible diurnal variations in sonographic imaging of the pancreas, 20 patients were repeatedly examined during the day and also during the night. No variations were seen in the imaging quality of the pancreas. Hence, sonography of the pancreas can be effected at any time without any preparatory work, whenever there is any pain or a significant sign in the upper abdomen.
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3895427
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It is shown by means of a case report on a calculus in the dilated pancreatic duct, that abnormalities in small structures such as the pancreatic duct can be revealed by ultrasound, using current gray-scale instrumentation.
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3895428
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Intraoperative fine needle aspiration cytology of the suspected pancreatic region was carried out in 14 patients with a preoperatively confirmed tumour of the pancreas. Sonographic assessment revealed a malignoma in six cases and chronic pancreatitis in eight cases. All sonographic findings were confirmed by puncture cytology; there was no false negative or false positive diagnosis. Fine needle aspiration cytology monitored via sonography can help to further reduce the incidence of false negative findings in intraoperative cytology and can exercise a decisive influence on surgical procedure by intraoperative sonography-monitored staging.
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3895429
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From March 1982 to September 1983 62 ultrasound-guided fine needle aspiration cytologies in 22 patients with cadaveric kidney transplants had been performed during the postoperative hospitalisation period. In any case it was possible to guide the needle tip into the cortico-medullary boundary or in sonolucent parenchymal areas occurring during acute cellular rejection episodes. Thus technical failures could be reduced to 6% (4 out of 22). In 79% the clinically suspected diagnosis could be confirmed by FNAC. Aspirates from circumscript sonolucent parenchymal areas allowed rejection diagnosis in 95%. In 17% cellular signs of rejection were seen cytologically despite a regular transplant function.
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3895430
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Impediography, a method for ultrasonic tissue characterisation, is theoretically and exerpimentally investigated. After a short description of the mathematical formalism ("Inverse Scattering Problem"), digital processing of broadband ultrasonic signals and measuring problems are discussed. The obtained results are completed by measurements on tissue structures in vitro. The paper shows the limits of the application of impediography if inhomogenous tissue structures are present.
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3895431
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Malignant haemangioendotheliomas of the liver are very rare mesenchymal tumours. Sonographically, they appear as solitary, although more frequently as multicentric, space-occupying growths with blurred and irregularly delineated outlines; the sonographic image shows both echo-dense structures and structures with a low amount of echoes, or which are even echo-free. Short-term sonographic follow-up examinations point to a tendency to rapid growth and varying echogenicity.
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3895433
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The construction of an expression plasmid of hepatitis B virus surface antigen (HBsAg) gene from the cloned hepatitis B virus (HBV) genome subtype adr is reported. The expression products of this plasmid in E. coli were detected by means of radioimmunoassay in competitive suppression and polyacrylamide-SDS gel electrophoresis. The presence of a fusion protein containing HBsAg was confirmed.
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3895432
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Sonographic examinations of 1 416 patients performed between 1980 and 1983 with particular reference to the inguinal, axillary and neck regions have shown that it is quite possible to effect sonographic differentiation between enlarged lymph nodes with cicatricial indurations after non-specific inflammation on the one hand, and primary lymphomas or metastases of lymph nodes on the other. In many cases, it is also possible to differentiate between the enlargement of a total lymph node (acute inflammatory, primary malignant) and metastases in a lymph node. Positive findings in the soft parts were seen in 278 patients; of these, 175 were confirmed histologically and cytologically (via puncture with sonographic control). One finding was revealed as false positive. In 102 patients the sonographic finding was confirmed by means of lymphographies (n = 12), computed tomography (n = 27) or via the subsequent clinical course, proving the fact that it is also possible to detect sonographically the ability of lymphomas to respond to treatment with antibiotics, cytostatics, and radiation; the effects can be recognised and interpreted via changes of the echo patterns.
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3895434
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To investigate the influence of the densely populated and heavily industrialized Rijnmond area of The Netherlands on the genotoxicity of the ambient aerosol, aerosol samples were collected at locations within the area, and at a coastal region located upwind. The mutagenicity of extracts of the samples was compared in the Salmonella/microsome test. The dependence of the effects on sampling time and on sampling location was investigated with the aid of a series of simple mathematical models. These models were also used to estimate the increase in mutagenicity above background levels at the sites in the Rijnmond area due to emissions within that area. Application of the models showed that the clear and significant increases are not merely a result of the additions of mutagens emitted, but that possibly interactions between sampling time- and location-dependent factors play a role. Comparison of the results obtained with the different Ames-test variants (different strains, with and without liver homogenate) indicate that the conclusions concerning the time and location dependence of the effect were not dependent on the variant used.
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3895435
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At least seven chromosome-sized DNA molecules (750 to 2000 kilobases in length and one fraction of undetermined molecular weight) from cultured clones and isolates of Plasmodium falciparum have been separated by pulsed-field gradient gel electrophoresis. Whereas asexual blood stages and sexual stages of the same line have identical molecular karyotypes, the length of chromosome-sized DNA molecules among different geographical isolates and several clones derived from a single patient is different. These length alterations of chromosomes are the result of DNA rearrangements that must occur unrelated to sexual differentiation.
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3895437
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A highly specific polyclonal rabbit antiserum directed against murine cachectin/tumor necrosis factor (TNF) was prepared. When BALB/c mice were passively immunized with the antiserum or with purified immune globulin, they were protected against the lethal effect of the endotoxin lipopolysaccharide produced by Escherichia coli. The prophylactic effect was dose-dependent and was most effective when the antiserum was administered prior to the injection of the endotoxin. Antiserum to cachectin/TNF did not mitigate the febrile response of endotoxin-treated animals, and very high doses of endotoxin could overcome the protective effect. The median lethal dose of endotoxin in mice pretreated with 50 microliters of the specific antiserum was approximately 2.5 times greater the median lethal dose for controls given nonimmune serum. The data suggest that cachectin/TNF is one of the principal mediators of the lethal effect of endotoxin.
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3895438
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The effects of vasoactive intestinal polypeptide (VIP) in the superior cervical ganglion of the cat were studied in vitro and in vivo with sucrose gap and multiunit recording, respectively. At a dose of 0.03 to 0.12 nanomole, VIP produced a dose-dependent, prolonged (3 to 15 minutes) depolarization of the ganglion and enhanced the ganglionic depolarization elicited by the muscarinic agonist acetyl-beta-methylcholine. At a dose of 1.8 to 10 nanomoles, the peptide enhanced and prolonged the postganglionic discharge elicited by acetyl-beta-methylcholine, enhanced muscarinic transmission in ganglia treated with an anticholinesterase agent, and enhanced the late muscarinic discharge elicited by acetylcholine. VIP did not affect the early nicotinic discharge elicited by acetylcholine or by electrical stimulation of the preganglionic nerve. It is concluded that VIP has a selective facilitatory action on muscarinic excitatory mechanisms in the superior cervical ganglion of the cat.
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3895440
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The multiplicity of data summarized in this review indicate a variety of signals built into the intrinsic structure of secretory, membrane-associated, and lysosomal glycoproteins, which direct these complex molecules toward specific cellular organelles. Some of these signals (such as the NH2-terminal signal segment) are discarded when the appropriate transfer has been completed. Others are retained as a permanent intrinsic component of the molecule. Although evidence has been presented that the carbohydrate moieties of glycoproteins are not essential for secretion, they probably subserve a role in the interaction of glycoproteins with membrane receptors on intracellular organelles. Undoubtedly, other examples of permanent molecular signals will be described in the future, which will provide a comprehensive picture of the integrated transport activity of the membrane channels of the secretory pathway of the hepatocyte.
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3895439
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Recent concepts suggest that there are specific interactions between cells and the components of the extracellular matrix. These are mediated via cell surface receptors for the glycoproteins, collagens, and proteoglycans of the matrix. Two types of reactions are postulated. Normal matrix components, that is, those that are indigenous to the tissue, induce functional competence in the cells. Trauma, inflammation, or related reactions induce the production of matrix components more typical of fibrotic tissues. These matrix components cause a shift in cellular activities as they engage cell receptors. Various mechanisms can prolong and augment the fibrotic response, leading to an irreversible loss of tissue structures and function. New methods are available for identifying the cells and species of matrix proteins active in disease states.
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3895447
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The location of red marrow related bone lesions is dependent upon the distribution of red marrow. It is altered by the normal conversion of red marrow to yellow (fat) marrow and by the reconversion of yellow marrow to red marrow caused by marrow infiltrating disorders or marrow stress disorders.
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3895448
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Despite criticisms of the quality of health care for women and considerable research on sex differences in illness behavior and utilization of health services, little research has addressed the potential impact of physician gender on the physician-patient relationship and its outcomes. With the entry of more women into the medical profession, opportunities to investigate effects of physician gender will increase. A theoretical rationale for expecting physician gender to affect the key dimensions of the interactive physician-patient relationship (communication of information, affective tone, negotiative quality) and its outcomes (satisfaction, compliance, health status) is presented. Physician gender might impact on the relationship through three mechanisms: sex differences among physicians, particularly with respect to sex-role attitudes; patients' different expectations of male and female physicians; or increased status congruence between physician and patient in same-sex, as compared to opposite-sex, physician-patient dyads. Recent research related to these topics is discussed and found to support the plausibility of these mechanisms of potential gender effects. Some methodological suggestions for future research are presented, including the suggestion that future research identify specific conditions under which physician gender effects might be more salient.
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3895449
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1046 non-hospitalized children and mothers from various regions of Liberia were studied to determine the relationships between their indigenous perceptions of malaria illness with on-going Plasmodium parasitemia and annual incidence of clinical malaria. Eleven pediatric and 14 maternal signs and symptoms of malaria were described, ranked by cultural severity, and evaluated biomedically. Between cultural perceptions of the severity of illness and biomedical evidence of the severity of disease, significant rank order correlations are observed for children (rho = 0.713, P less than 0.01) and mothers (rho = 0.875, P less than 0.001). Clinical, parasitological and cultural concordance were observed for 'anorexia', 'joint pain', 'abdominal tenderness', 'nausea', 'chills', 'severe headache', 'stomach pain', and 'dizziness'. Five other symptoms however either over or underpredicted observed levels of biomedically confirmed malaria: 'fever', 'convulsions', 'vomiting', 'body weakness' and 'psychological distress'. Biomedical studies revealed a parasite rate among children of 68.6%, a mean annual incidence of pediatric clinical malaria of 3.12; and a mean annual incidence of maternal clinical malaria of 2.42. Clinical malaria demonstrated a very early onset among newborns and a shift in acute parasitemia to a chronic status around 2.3 years of age. A significant positive linear correlation (r = 0.75, P less than 0.01) was observed between parasitological and clinical measures of malaria in children. The indigenous perspectives on malaria and the biomedically predictive powers of various biocultural symptoms are discussed and evaluated as an integrative and valuable means of assessing the impact of malaria in an endemic region.
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3895451
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We have reported the fifth case of endocarditis due to Salmonella enteritidis and the first known survivor of native aortic valve endocarditis from this pathogen. Despite appropriate antibiotic therapy, aortic valve replacement was necessary because of heart failure and embolism. The patient also had concurrent viral hepatitis B infection.
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3895450
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At the beginning of October 1919 doc. MUDr. Frantisek Prokop came to Bratislava to organize and build the Institute of Forensic Medicine of the Medical Faculty of the Comenius University. The submitted investigation, based on assembled documents, gives an account of the existence and activities of this department. The Institute had to be built from scratch; during the first years it was inadequately equipped and understaffed. In 1925 MUDr. Herman Krsek became one of the assistants and in 1935 he was awarded the title of reader in forensic medicine.
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3895452
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The following summary of the physiologic and epidemiologic evidence may help the clinician in making decisions when caring for persons with ISH: ISH is predominantly found in older age groups, being present in 1% to 4% of the population under age 40, 10% to 15% between ages 60 and 70, and 25% to 30% over age 70. ISH is more prevalent in women than in men. The development of ISH in the aged is associated with a decrease in arterial compliance. The relationship whereby ISH is both a cause and a result of atherosclerotic vessels needs further delineation. Neurohumoral factors also have a part in determining arterial compliance. An elevated SBP is an important contributor to the risk of developing coronary artery disease, and in persons over 45 years old it is a more powerful predictor of coronary events than DBP. SBP is a better discriminator of risk for strokes at all ages than DBP is. The relative risk in persons with ISH for the development of coronary artery disease and stroke is two to five times that of normotensive persons, but is no worse than the risk for these events among treated hypertensives. Although the relative risk of ISH is not strikingly large, the high prevalence of ISH among aged individuals, the increasing size of the population over 65 years old, and the high incidence rate of cardiovascular events in the aged give ISH a sizable attributable risk in the population (13 to 28 deaths per 1,000 individuals). It remains to be shown that lowering SBP in ISH removes the risk of ISH. Studies are needed that monitor the costs and adverse effects of therapy as well as the possible benefits when a condition such as ISH is most commonly seen in the aged.
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3895453
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Recognition of the condition of diabetes mellitus and speculation as to its dietary treatment spans the period from its earliest mention in the Papyrus Ebers, before Christ, to the most recent publication of the American Diabetes Association. The relationship of carbohydrates to protein, fats, and total calories has consistently engaged the minds of clinicians over the centuries. Various combinations have been used, some highly unpalatable and some bordering on starvation; but to date our knowledge regarding the metabolic consequences of various dietary regimens is incomplete and in need of further research. The composition of a diet that will result in the best blood glucose control for diabetic persons is uncertain and controversial. Whether dietary changes can significantly delay or prevent long-term complications of diabetes has also been questioned. The insistence that a diabetic person rigidly adhere to a specific diet cannot be defended scientifically.
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3895455
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The terpenoid lactone nimbolide, the structure of which has been unambiguously established, was found to inhibit Plasmodium falciparum in culture with a moderate potency. The EC50 against the parasite line K1 from Thailand was approximately 2.0 microM (0.95 microgram/ml). The EC50 of crude aqueous extract of Azadirachta indica var. siamensis (Sadao tree), was 115 micrograms/ml, and of crude ethanol extract was 5.0 micrograms/ml. Since nimbolide is a major constituent in these extracts, it could account substantially for their inhibitory activity. However, neither the crude extracts nor nimbolide showed any activity in vivo against Plasmodium berghei in the mouse either through ingestion (746 mg aqueous extract, 62.5 mg ethanol extract or 12.5 mg nimbolide/kg/day), or subcutaneous injection (93 mg aqueous extract, 31 mg ethanol extract or 12.5 mg nimbolide/kg/day).
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3895456
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Sixty-three strains of E. coli transconjugants derived from E. coli K12 J62-1 containing plasmids derived from Klebsiella pneumoniae, were examined for the presence of phenotypic markers other than antibiotic resistance. This investigation was carried out using API 50CHE and API ZYM tests. Beta-glucosidase was found in 63/63 J62-1 transconjugants. Dulcitol dehydrogenase was present in 92.1% while beta-galactosidase was present in 70% of transconjugants. None of the three enzymes were present in the recipient. Dulcitol dehydrogenase was present only in the transconjugants and is absent from the donors and recipient. The transconjugants, cured of their antibiotic resistant plasmids retained dulcitol dehydrogenase activity. The Klebsiella donors were not cured of antibiotic resistance by the curing process.
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3895463
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The observation that decreased thymidylate supply in vitro induces the expression of the Xq27 chromosome fragile site prompted us to examine cellular thymidylate metabolism. Using a sensitive enzyme assay for deoxyribonucleotide triphosphates, we found that the total cellular thymidine triphosphate pools in cell lines from fragile X patients and carriers do not differ from normal controls under either basal or folate-deficient conditions. This agrees with our earlier observation that the thymidylate synthase enzyme activities in crude cell extracts of five fragile X syndrome lymphoblast lines do not differ from those in normal controls under standard assay conditions. Although a difference in the amount of thymidine triphosphate available at the replication fork for DNA synthesis remains a possibility, our results indicate that a readily demonstrable defect in thymidylate metabolism is not present in fragile X syndrome cells.
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3895467
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A 31/2-month-old girl with juvenile osteopetrosis is described. She presented with failure to thrive, a blocked nose, anaemia and hepatosplenomegaly and had dense sclerotic bones on radiography. This disease, which is potentially lethal, may be cured by bone marrow transplantation in selected cases.
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3895468
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A mixture of enzymes (mycolase) capable of lysing yeast cell walls was prepared from culture filtrates of Physarum polycephalum. The enzymes present in mycolase included chitinase, beta-1,3-glucanases and exo-glycosidases. The pH optima of these enzymes were in the range 3.5-5.0 and they had low activities at pH 7.0. Mycolase produced spheroplasts from Candida pseudotropicalis and, unlike commercial enzyme preparations such as L1, chitinase, beta, 1,3-glucanase and beta-glucosidase, had some candicidal activity in vitro against C. pseudotropicalis and C. albicans. Mycolase potentiated the antifungal activity of amphotericin B against C. pseudotropicalis grown in shake flask culture but did not potentiate the antifungal activity of the antibiotic against similar cultures of C. albicans; indeed antagonism between mycolase and amphotericin B was sometimes observed with the latter yeast. Mycolase caused an approximately two-fold increase in the total and viable counts of cultures of C. albicans inoculated with stationary phase cells. These increases, which were observed within about 30 min, were attributed to mycolase inducing the premature release of viable buds from 'lag' phase cells. Mycolase also increased the rate at which C. albicans formed germ tubes when the yeast was cultured in a medium containing serum. Mycolase alone or in combination with amphotericin B did not appreciably enhance phagocytosis or intracellular killing of the yeasts by unstimulated mouse peritoneal macrophages. Studies on mice infected systemically with C. albicans showed that mycolase only slightly enhanced amphotericin B therapy.
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3895469
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An exocellular proteinase produced by Trichophyton rubrum in a glucose-peptone broth was purified from lyophilized and dialysed culture filtrate of the dermatophyte by Sephadex G-100 gel filtration and preparative polyacrylamide gel electrophoresis. The purified enzyme was a homogeneous protein of molecular weight 34700 and it could hydrolyse azoalbumin, casein, bovine serum albumin, alpha-N-benzoyl-L-arginine ethyl ester and p-toluenesulfonyl-L-arginine methyl ester but not N-benzoyl-L-tyrosine ethyl ester, alpha-N-benzoyl-DL-arginine-p-nitroanilide and keratin. The enzyme showed an alkaline pH optimum and was not activated by divalent metal ions but inhibited strongly by phenylmethylsulfonylfluoride. Thus the enzyme was identified as an alkaline serine proteinase.
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3895530
|
This article is adapted from the Summary of the 1985 Annual REPORTS of the Medicare Board of Trustees. It presents the actuarial status of the Hospital Insurance (HI) and the Supplementary Medical Insurance (SMI) Trust Funds. Two actions favorably affecting the financial status of the HI Trust Fund have occurred since the publication of the 1984 REPORTS: (1) Fiscal year 1986 hospital payment rates will continue at the same level as in fiscal year 1985, and (2) the level of the annual increase in the rates that can be granted without specific justification has been reduced. Despite these two actions, the Board found that the present financing schedule is barely sufficient to ensure payment of benefits through the late 1990's if the assumptions underlying the estimates are realized. The Board found the SMI program to be financially sound, but it noted with concern the rapid growth in the cost of the program. For both HI and SMI, the Board recommends that Congress consider ways to curtail the rapid growth in program costs.
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3895532
|
Eighty-nine patients who underwent elective operations and 26 patients who underwent nonelective operations for diseases of the large intestine were studied for mortality and morbidity. In the patients who underwent elective operations, there was no anastomotic leakage or wound infection and only 1 per cent mortality. Additionally, 2 per cent nonfatal surgical complications were observed. In patients who underwent nonelective operation, a morbidity of 46.2 per cent and a mortality of 15.0 per cent were observed. Fourteen patients with acute illness were without serious complications postoperatively. All anastomoses except two were one row in elective operations without protective colostomy. All patients who underwent elective operation received antibiotic prophylaxis-a combination of cefotaxime and metronidazole.
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3895535
|
Since prostacyclin (PGI2) is known to regulate renal cortical blood flow and since ischemia stimulates thromboxane (Tx) A2 synthesis, the role of these prostanoids in moderating the response to renal ischemia was studied in the rat. At baseline, plasma TxB2 concentration in untreated animals (n = 13) was 357 pg/ml. The left renal pedicle was clamped for 45 minutes after a right nephrectomy (n = 16), which led after 5 minutes of reperfusion to a rise in TxB2 to 2825 pg/ml (p less than 0.001), but there was no change in 6-keto-PGF1 alpha. After 24 hours creatinine levels rose from 0.4 to 3.0 mg/dl (p less than 0.001), and left renal weight rose from 94% to 117% (p less than 0.001) relative to the weight of the right kidney. In nephrectomized but nonischemic sham control rats (n = 7), creatinine level was 0.9 mg/dl and kidney weight 91% after 24 hours. Pretreatment with OKY 046 (n = 13) (2 mg/kg administered intravenously) blocked ischemia-induced TxB2 synthesis, while 6-keto-PGF1 alpha levels rose from 96 to 302 pg/ml (p less than 0.001). There was no increase in creatinine levels or kidney weight relative to the sham group. Pretreatment with ibuprofen (n = 10) (12 mg/kg) or OKY 046 and ibuprofen (n = 9) inhibited TxB2 and 6-keto-PGF1 alpha synthesis, but creatinine levels and renal weight rose (p less than 0.001). Renal histology in OKY 046-pretreated animals was equal to that in nephrectomized controls, while all other ischemic groups showed tubular necrosis. Results indicate that a high PGI2/TxA2 ratio protects against renal ischemia.
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3895536
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That local splanchnic ischemia is associated with the acute gastric "stress" erosions seen in shock is well established. The hemodynamic mechanism mediating that ischemia is unknown. Pericardial tamponade was produced in anesthetized pigs while hemodynamic parameters were monitored in the systemic circulation as a whole and in the vascular beds of the celiac and left gastric arteries, respectively. Stepwise increases in pericardial pressure produced progressive decreases in arterial pressure and cardiac output (i.e., reproducible, quantitable, and rapidly reversible levels of cardiogenic shock). This produced a profound reduction in blood flow in the celiac and gastric beds that was significantly disproportionate to the reduction in cardiac output. This was due to significant increases in celiac and gastric vascular resistance that were more than twice as great as those seen in the systemic circulation as a whole (i.e., selective splanchnic vasoconstriction). This response was abolished by ablation of the renin-angiotensin axis, whether by bilateral nephrectomy, captopril, or saralasin, and mimicked, without tamponade, by the infusion of angiotensin II. Levels of celiac artery blood flow and resistance correlated significantly with endogenous levels of plasma renin activity. On the other hand, this response was not abolished by confirmed alpha-adrenergic blockade (phenoxybenzamine) or by sympathectomy. In this model, cardiogenic shock produces regional splanchnic ischemia in the celiac and gastric vascular beds by inducing a severe and disproportionate vasospasm that is mediated primarily by the renin-angiotensin axis.
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3895537
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Reports of improved survival of allografts in recipients of donor-specific blood prompted an attempt to determine the relationship of the antigenic composition of the blood product transfused to the development of immunologic unresponsiveness in rats. Cardiac allografts were transplanted from Fischer, Brown-Norway (BN), and Lewis (L) X BN (LBN) f1 hybrids to recipients treated with three weekly transfusions of 1 ml of donor-specific whole blood, erythrocytes, or ultraviolet-irradiated whole blood. Despite moderate improvement in survival with whole blood alone in the LBN- greater than L group (11.6 +/- 1.0 days), it was only with the ultraviolet-irradiated whole blood that marked prolongation was seen in all three strain combinations: Fischer- greater than L: 25.5 +/- 5.2, LBN- greater than L: 17.3 +/- 1.2, and BN- greater than L: 11.1 +/- 0.4 days compared with respective controls: 10.3 +/- 1.2, 7.3 +/- 0.5, and 7.4 +/- 0.6 days. Unlike reports for renal allografts, erythrocyte suspensions provided minimal protection for the cardiac allografts (14.2 +/- 0.8, 9.0 +/- 1.1, and 11.0 +/- 0.4 days, respectively), and adjunctive treatment with antilymphocyte serum had a similar small effect (16.3 +/- 1.4, 13.4 +/- 1.9, and 8.3 +/- 0.8 days, respectively). The elimination or inactivation of functional class 2 major histocompatibility complex antigens from the blood used for donor-specific blood transfusion may be an effective means of prolonging allograft survivals over those seen with whole blood alone; however, the degree of resultant unresponsiveness is still clearly influenced by dosage schedule, the organ transplanted, histocompatibility barrier, and adjunctive immunosuppression.
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3895538
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The interdependence between immunologic events occurring within acutely rejecting rat cardiac allografts and those in host lymphoid tissues were studied. To evaluate cellular dynamics of allograft infiltration, 111In-labeled thoracic duct lymphocytes from Lewis rats were administered intravenously daily (0 to 7 days after transplantation) to (Lewis X BN)F1 heart-grafted unmodified Lewis rats, sacrificed 24 hours later. Accumulation of thoracic duct lymphocytes in the allografts peaked 4 to 5 days after transplantation. To evaluate whether these changes at the graft site were sufficient to carry on the rejection response in the absence of a sustained host immunologic drive, acutely rejecting (Lewis X BN)F1 cardiac allografts were retransplanted serially at days 1 through 5 into normal syngeneic animals. All these regrafts survived greater than 100 days. Neither infusion of interleukin-2-conditioned medium (100 IU for 7 days intravenously) into regrafted hosts nor preoperative perfusion of the retransplanted hearts with interleukin-2-conditioned medium (300 IU) could complete the rejection process. Using flow cytometry analysis, we then assessed the phenotypic alterations of the mononuclear cells infiltrating the graft. The ratio of T helper: T cytotoxic/suppressor cells, which at day 3 was 1.57, inverted abruptly to 0.67 by days 5 to 6. After retransplantation a dramatic depression in T-lymphocyte subsets occurred, particularly affecting the T cytotoxic/suppressor phenotype. Trafficking studies revealed that the T cells that left the regrafts migrated mainly to spleen and mesenteric lymph nodes and away from bone marrow and peripheral blood of the syngeneic secondary recipients. Finally, histologic manifestations of acute rejection at days 4 to 5 virtually reversed themselves after regrafting. These studies emphasize the systemic nature of the rejection cascade, which depends fully on the host lymphoid system; even late changes in the graft microenvironment are not sufficient to produce final immunologic destruction.
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3895539
|
A prospective, randomized study of 49 mismatched living, related donor renal transplants was undertaken to compare the effect of donor-specific transfusions (DST) combined with conventional immunosuppressive therapy (azathioprine, prednisone, and antilymphoblast globulin) to cyclosporine and prednisone with and without use of prior DST. The results demonstrated that cyclosporine and prednisone without DST have equal patient and graft survival rates after transplantation and an equal incidence of infectious complications and rejection episodes when compared with recipients who received DST and conventional therapy. Patients who received DST and subsequent cyclosporine had poor graft survival rates with more rejection episodes and infectious complications. Hospitalization and the relative cost of transplantation were decreased when recipients received cyclosporine without prior DST. It is concluded that cyclosporine allows easier access to transplantation, is more cost effective in the initial posttransplant period, and does not subject the recipient to the risk of donor sensitization as is seen with DST recipients given conventional therapy. The nephrotoxic side effects of cyclosporine have been minimal and renal function remains excellent in the recipients treated with cyclosporine.
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3895540
|
To study the role of antibodies in promoting survival during gram-negative bacterial sepsis, we have developed several murine monoclonal antibodies (MAbs). One MAb (5B10) reacted in an enzyme-linked immunosorbent assay with only a single organism (Escherichia coli 0111:B4), while the other (8A1) reacted to all gram-negative whole-cell and lipopolysaccharide (LPS) antigens examined. Either 5B10 MAb, 8A1 MAb, or sterile saline solution was administered intravenously to outbred male Swiss-Webster mice immediately before one of three challenges: (1) viable bacteria intravenously, (2) viable bacteria with hemoglobin intraperitoneally, or (3) intravenous actinomycin D plus LPS. 5B10 MAb provided significant protection against either an E. coli 0111:B4 bacterial or LPS challenge but not against any other organism or type of LPS. 8A1 MAb provided protection against several challenge bacteria (intravenously or intraperitoneally) and against all types of LPS studied except Pseudomonas aeruginosa LPS. A higher dose (2 mg) of cross-reactive antibody (8A1 MAb) was required to produce protection when compared with the type-specific protection produced with 5B10 MAb (0.1 mg). Although ideal antibody therapy would consist of directing a specific MAb against a single microorganism, the acute nature of the disease process and time required to prepare reagents may preclude the use of type-specific MAbs. We believe that the cross-reactive and cross-protective capacity of 8A1 MAb or a similar MAb may be useful in averting the lethal effects of clinical gram-negative bacterial sepsis and warrants testing in the clinical setting.
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3895541
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Responses to bacteremia include fever, leukocytosis, elaboration of acute-phase proteins, hypoferremia, and increased protein catabolism. To evaluate the role of prostaglandins in the mediation of these responses, the effects of intravenous ibuprofen (12.5 mg/kg X dose) were studied in eight dogs infused with live Escherichia coli. Thirteen dogs served as noninfected controls. Two of the eight animals that received ibuprofen died during the study, whereas all control animals with sepsis survived. Prostaglandin inhibition prevented the rise in temperature resulting from sepsis, while alterations in white cell count, C-reactive protein, and serum iron levels were unaffected. In addition, protein catabolism appeared to be similar in both groups. This minimal metabolic effect coupled with observed renal side effects makes the use of nonsteroidal, anti-inflammatory agents in sepsis of questionable benefit.
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3895542
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To investigate the metabolic effects of interleukin-1 and its role as a mediator of host responses to trauma and sepsis, we injected seven healthy male subjects with etiocholanolone, an inflammatory agent that stimulates systemic responses thought to be mediated by interleukin-1. The subjects were fed a constant diet during each 4-day study and received three daily intramuscular injections of etiocholanolone, 0.10 mg/kg. Etiocholanolone injection resulted in inflammation, fever, leukocytosis, increased serum C-reactive protein, hypoferremia, and increased plasma activity of interleukin-1/lymphocyte-activating factor. Plasma concentrations of the counterregulatory hormones were normal. Protein metabolism, as reflected in nitrogen balance, 15N turnover, and forearm flux of alanine and glutamine, was unaltered. Serum glucose and insulin levels and tissue responsiveness to insulin were normal. This dissociation of acute-phase and catabolic responses may reflect the magnitude of the stimulus; higher levels of interleukin-1 may initiate catabolic responses. Alternatively, other mediators such as the counterregulatory hormones may direct the catabolic responses that occur after injury and sepsis.
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3895543
|
In this study the sequence of histologic changes in rejecting pancreatic allografts was correlated with the recurrence of hyperglycemia to evaluate the usefulness of serum glucose monitoring in pancreas transplantation. In addition, various immunosuppressive agents were evaluated for their efficacy in reversing rejection. Diabetic (streptozocin) Lewis rats were recipients of histoincompatible Lewis X Brown Norway F1 pancreatic grafts, which uniformly resulted in a fall in serum glucose levels from greater than 400 mg/dl to less than 150 mg/dl. Specimens were examined daily from the time of transplantation to determine the time of earliest histologic rejection. Functional rejection was defined as a rise in serum glucose levels to greater than 200 mg/dl and occurred at 8.5 +/- 0.8 days in the control group. Histologic evidence for rejection was present by day 3 as a perivascular lymphoid infiltrate while islets remained normal. Extensive cellular rejection of the exocrine tissue occurred by day 6 when most recipients were still normoglycemic. Complete pancreatic destruction was present by day 9. Antirejection therapy with methylprednisolone (MP), antithymocyte serum (ATS), or cyclosporine (CS) started at the time of recurrent hyperglycemia (days 8 or 9) and was uniformly unsuccessful in prolonging graft survival, with mean survival times of 8.3 +/- 0.8 (MP), 9.0 +/- 0.7 (ATS), and 9.3 +/- 0.4 (CS). In contrast, either ATS or CS but not MP begun on day 3, when histologic rejection was first observed, significantly prolonged graft survival to greater than 11 days in most recipients. We conclude that islet destruction is irreversible by the time that marked elevation in serum glucose levels occurs and therefore a more sensitive measure of pancreas rejection is needed. Furthermore, ATS and CS are more effective than are corticosteroids in reversing early rejection.
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3895544
|
In the 1970's economic factors dictated the development of alternatives to gold alloys in dentistry in the USA and in Europe. A similar development has not occurred in Sweden because of different laws. Alloys that contain nickel and beryllium present a health hazard and are therefore of little interest to the Swedish market. A review of the literature shows that castings of base-metal alloys are less accurate than castings of conventional gold alloys and of low gold alloys. However, in long-span-bridges and in thin resin-bonded cast restorations, their physical and mechanical properties are superior to those of the gold alloys. In this study the casting accuracy of a nickel- and beryllium-free cobalt-chromium alloy, Neobond II Special, is investigated. Neobond II Special was found to be less accurate than Sjödings C-guld. The marginal discrepancies of the castings were small, however, when the castings were oversized. It also proved to be technique sensitive to conventional dental laboratory procedures. Thus, it seems difficult to get castings with an acceptable retention as well as small marginal discrepancies when using the base-metal alloy.
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3895545
|
376 three-year old children were divided into four experimental groups and exposed to different combinations of preventive programs for a period of two years. All the groups were given the same basic prophylactic information. Additionally Group I received fluoride tablets (FLUDENT) for daily sucking twice a day plus a placebo dentifrice free of fluoride. Group II was given a fluoride dentifrice containing 0.025% F, (ACTA). Group III was given a placebo dentifrice plus fluoride varnish (Duraphat) twice a year. Group IV a fluoride dentifrice containing 0.025% F (ACTA) plus fluoride varnish (Duraphat) twice a year. No statistically significant difference in caries increment during the two experimental years was found between the groups. A tendency to lower caries increment was found in Group IV, i.e. in the children using the low fluoride dentifrice and treated twice a year with fluoride varnish.
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3895549
|
The clinical, bacteriological, cytological, serological and allergological data were analyzed in 376 patients with acute pneumonia and chronic bronchitis to study the diagnostic importance of the microorganisms isolated from the sputum. The informativeness of the methods was estimated by correlation of the appropriate data with the data of the final verified diagnosis of the inflammatory process in the lungs. Bacterioscopy of the sputum smear stained according to Gram, bioassay on mice, determination of bacterial concentration per ml sputum, allergic tests with bacterial allergens were found to be the most reliable methods as regards the etiological diagnosis of acute pneumonias. It should be mentioned that bacterioscopy is an early criterion of the disease etiology. Criteria of the etiological significance of bacteria which cause exacerbation of chronic bronchitis encompass the measurement of bacterial concentration per ml sputum, indirect immunofluorescence with autostrains of the isolated bacteria and the bioassay. Early criteria include the first two methods.
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3895550
|
A study was made of immunologic cell markers in 32 patients with acute myeloid leukemia by indirect immunofluorescence with the aid of xenogeneic antisera and monoclonal antibodies obtained by the authors. Ia-like antigen demonstrated by monoclonal antisera IKO-I expressed in myeloblastic leukemia with maturation in myelomonoblastic leukemia and in all patients with monoblastic leukemia. Antigen of EK-cells demonstrated by monoclonal antibodies IKO-II was found in 10 out of 18 patients. The number of antigen positive cells correlated with the number of monoblasts. One out of 22 patients showed 19% of cells which express with OLL antigen. In 2 out of 18 cases, the blast cells carried T-cell antigens. A remission was attained in 1 out of these 2 patients treated similarly to patients with OLL.
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3895554
|
In a previous study on 27 patients with chronic bronchitis we found that only three developed bronchoconstriction in response to hyperventilation of cold, dry air despite an increased responsiveness to methacholine inhalation. We therefore investigated bronchial responsiveness to hyperventilation with cold, dry air and methacholine in 27 patients with stable asthma who had a similar range of baseline FEV1 values but who developed bronchoconstriction that could be reversed to give an FEV1 more than 70% of the predicted value. Baseline FEV1 was 0.88-3.98 l (37-114% predicted). All but one subject developed bronchoconstriction in response to hyperventilation. There was a linear relationship between baseline FEV1 and response to methacholine (r2 = 0.37, p less than 0.001) and the relationship was significantly different from that found in the bronchitic subjects (F2.50 = 24.94, p less than 0.001). In general, the response to methacholine was greater in the asthmatic than in the bronchitic subjects for any baseline FEV1. The results suggest that there are different mechanisms underlying the increased responsiveness to methacholine in asthma and chronic bronchitis.
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3895555
|
Responsiveness to inhaled methacholine was compared before and 40-60 minutes after a challenge with ultrasonically nebulised water (UNH2O) in 16 asthmatic patients. The sensitivity to methacholine increased after UNH2O challenge (p less than 0.001). The mean dose of methacholine producing a 20% fall in forced expiratory volume in one second was 0.4 (95% confidence limits 0.2, 0.8) mumol, compared with 0.9 (95% confidence limits 0.5, 1.6) mumol in the first methacholine challenge. When the study was repeated in six asthmatic patients with histamine substituted for methacholine, five of the patients were significantly more sensitive to histamine after UNH2O challenge. It is concluded that challenge with UNH2O produces an increase in airway responsiveness.
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3895558
|
Changes in the coagulation system typical of consumption reaction, microthrombosis in the lungs and other organs and haemodynamic disturbances caused by infusion of endotoxin in weaned pigs were prevented by treatment with the serotonin receptor antagonist cyproheptadine.
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3895561
|
The role of thrombus-binding in the fibrinolytic response to the acylated streptokinase.plasminogen activator complex, BRL 26921, has been examined using human plasma clots, radiolabelled with 125I-fibrin, in vitro. When clots were briefly exposed to BRL 26921, washed and returned to homologous plasma, lysis continued for up to 3 hours and attained approximately 25% of that lysis achieved by incubating with BRL 26921 for 5 hours. This continuing lysis was potentiated by return of exposed clots to alpha 2-antiplasmin-depleted plasma, or buffer and is attributed to an initial uptake of BRL 26921 rather than the binding of exogenous plasmin that was observed for streptokinase and high concentrations of urokinase. The sustained lysis is not explained by transfer of loosely-associated surface material or by dissociation of agent from the clot with reuptake from a dilute systemic pool. The response can be attributed, at least in part, to specific fibrin binding, mediated by kringles 1-4, for a low-molecular weight plasminogen (Val442) variant was less active.
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3895560
|
Antithrombin III (AT III) is increased in situations where there is increased platelet turnover. Plasma AT III levels measured in 39 renal transplant recipients were significantly higher than in 20 healthy subjects (p less than 0.001) and 20 patient controls (p less than 0.025). AT III levels were significantly correlated with the patients' platelet counts (r = 0.4, p less than 0.02). Transplant patients with less than 1 year follow up had significantly higher AT III levels than patients with more than 1 year follow up (p less than 0.01). All 5 patients with transplant rejection in the study had elevated plasma AT III levels. The data suggest that elevation of plasma AT III may be related to graft rejection.
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3895563
|
Heterogeneity of rat plasma fibrinogen gamma chains (gamma A, gamma') is due to differential splicing of the primary mRNA transcript. Human gamma' chains, which amount to 7% of the total gamma chain population of plasma (hepatic) fibrinogen, are not detectable in fibrinogen isolated from platelets. In this investigation, we extended our studies to rats and found that gamma' chains, representing 30% of the rat plasma gamma chain population, are not detectable in their platelet fibrinogen.
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3895564
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The hemodynamic effects of intracoronary administration of a fibrin (ogen)-derived peptide B beta 30-43 (Arg-Pro-Ala-Pro-Pro-Pro-Ile-Ser-Gly-Gly-Gly-Tyr-Arg-Ala) were evaluated in open-chest anesthetized dogs. Coronary blood flow (CBF) increased and coronary vascular resistance (CVR) decreased with intracoronary administration of peptide B beta 30-43. These changes were dependent on the amount of the peptide B beta 30-43 administered. There were no significant effects of peptide B beta 30-43 on aortic & left ventricular end-diastolic pressures. Plasma 6-keto-PGF1 alpha (stable hydrolysis product of PGI2) concentrations increased in coronary sinus blood samples in conjunction with increase in CBF. Intravenous administration of indomethacin (5 mg/kg) inhibited the release of PGI2 and almost completely abolished the effects of the fibrin(ogen)-derived peptide on CBF. This study suggests that this fibrin (ogen)-derived peptide has potent effects on the coronary vascular bed of the dog, and that these effects are in large part mediated through PGI2 release. These coronary hemodynamic effects of fibrin(ogen)-derived products may have important autoregulatory effects in atheromatous coronary circulation, wherein thrombi may form spontaneously.
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3895562
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An enzyme-linked immunosorbent assay (ELISA) for measuring human protein C by using two monoclonal antibodies directed toward the heavy chain of protein C is reported. This assay enabled the determination of protein C in concentrations of 10 to 400 ng/ml in less than 3 hours with a single antigen-antibody reaction. Within-run and between-run coefficients of variation were less than 8%. The mean concentrations of protein C in plasma of 42 normal subjects, 24 patients with liver disease, 27 with DIC, 48 with warfarin therapy and 15 with congenital protein C deficiency, were 4.2, 3.0, 2.3, 2.1 and 1.9 micrograms/ml, respectively. The results obtained with the present ELISA correlated well with those of radioimmunoassay (r = 0.935, n = 81) as well as those of Laurell's Rocket method (r = 0.910, n = 81) by using rabbit anti-human protein C serum. The present method was sensitive and specific for measurement of protein C and also PIVKA-protein C in plasma.
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3895567
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The frequency of human infections caused by Campylobacter (C.) jejuni is thought to be at present as significant as that of infections with salmonella. The epidemiology of human infections with C. jejuni is not well understood, although numerous species of animals are an important reservoir for this microorganism. In an overview the occurrence of C. jejuni at different domestic animals and pets is described. There is also given a report about possible direct and indirect ways for the infections from animals to man.
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3895568
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Contagious pustular dermatitis (CPD, contagious ecthyma, Orf) is a highly contagious viral disease afflicting sheep and goats. The infectious agent is a parapoxvirus which is widespread and also contagious for humans (zoonosis). Recently the disease in sheep and goats is marked by increased incidence and severe cases which cause many losses especially among lambs in fattening farms. The immunity of once infected animals is based on cellular defense mechanisms which are very unstable. The most suitable method for the prevention of ecthyma is parenteral vaccination with attenuated live vaccines. Effective vaccination programmes should enclose the whole animal population at intervals of 6-8 months.
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3895569
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Bumblefoot is an inflammation of the talons of birds of prey which can be caused by various (exogenous and endogenous) factors. Falcons and eagles suffer more than other species of prey from this complaint. Affected birds show all stages from acute to chronic inflammation. Bumblefoot must be distinguished diagnostically from pox-infections and skin tuberculosis. To a large extent the inflammation can be prevented by providing the bird with a properly designed perch, with a correct diet, and with adequate grooming. Surgical treatment is the only promising therapy, though the chances of success depend on the extent of the inflammation. Generally all healing processes in region close to the talons are difficult and lengthy.
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3895570
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The stomach worm of the cat with an unusual cycle has a special place among the nematodes. O. tricuspis can develop and breed endogen as well as exogen, the infection of other hosts with freedom of movement, takes place through the ingestion of vomitus material containing parasites. As the conventional coproscopic methods of routine diagnosis have failed, the examination of gastric mucus or gastric mucosal scrapings post mortem offers itself. Intra vitam a provocated vomitus or a gastric irrigation are the diagnostic methods of choice. Increased vomiting of unknown genesis should, however, evoke suspicion relating to an O. tricuspis-infection and suggest an examination of the material. Besides the cat, dog, pig, wild cat, fox, cheetah, lion and tiger act as natural or inadequate hosts. Pathological alterations or clinical symptoms are more obvious in unusual carriers of parasites. Therapeutically only Citarin 2,5% was convincing.
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3895571
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The article reports important diseases and different farming techniques of nutria. E. coli and salmonella infections are the most important bacterial diseases. Coccidiosis and strongyloidosis are frequently observed in nutria farms. Differentiated prophylactic treatment and hygiene are necessary for optimal breeding conditions.
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3895572
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The history of araneidism is long and confusing. The superstition seems to be inexterminatable that tropical mygalomorphs and mediterranean tarantulas are dangerous for humans. It can be looked up even in the most recent edition of the widespread clinical dictionary of Pschyrembel. In contrast to this certain ctenids, the most dangerous spiders up to now known, are mentioned not at all in medical publications. Exaggerated spider-fear is out of place because about 0.1% of all species are dangerous for man only and many of the venomous species live as hidden as they scarcely come in contact with humans.
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3895573
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Human placenta specimens obtained at term were investigated for distribution of fibronectin, collagens and glycosaminoglycans. When examined by the immunofluorescence staining technique with anti-plasma fibronectin antiserum, fibronectin was shown to be present around the fetal blood vessels and in the stroma of placental villi. The distribution of type IV collagen also was examined with specific antiserum. It was found that its distribution was similar to that of fibronectin. Conventional alcian blue staining indicated that the placental villi contained only small amounts of glycosaminoglycans. These data suggest that fibronectin and type IV collagen play important roles in tissue organization of the placental villi.
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3895575
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In order to elucidate the mechanism of the bronchial response of monkeys to constrictive stimuli, the effects of pretreatment with aerosolized lidocaine, atropine, and isoproterenol were studied. Treatment with aerosolized lidocaine and atropine not only extinguished the cough reflex, but also decreased bronchial susceptibility to aerosolized methacholine. Moreover, the pretreatment with lidocaine blocked the histamine challenge, but atropine did not. The aerosolized lidocaine decreased the bronchoconstriction induced with methacholine, but not with histamine. Pretreatment with over 1% of isoproterenol did not extinguish the cough reflex. However, this dose of isoproterenol did suppress an increase in Rrs due to the challenge of both methacholine and histamine. Isoproterenol also decreased the bronchoconstriction due to the previous challenge by both methacholine and histamine. The antagonistic effects of lidocaine, atropine, and isoproterenol on the broncho-constriction of monkeys are discussed in relation to the subepithelial receptor.
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3895574
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To assess the role of inactive renin in hypertensive patients, active, inactive and total renin concentrations (ARC, IRC and TRC) were measured in 37 patients with hypertension of various etiologies. Inactive renin was activated by trypsin and renin concentration was measured using an excess of sheep substrate. Mean values of ARC, IRC, TRC and active renin ratio (AR ratio = ARC/TRC) were higher in 6 cases of renovascular hypertension, and lower in 6 cases of primary aldosteronism and 1 case of idiopathic hyperaldosteronism, when compared with 59 cases of normal subjects. Between ARC and IRC, a slightly positive correlation was observed. Moreover, between ARC and TRC as well as between ARC and AR ratio, close positive correlations were observed. Exceptionally, in a case of juxtaglomerular cell tumor, AR ratio was low in spite of the extremely high value of ARC. Our data suggest that the increase in circulating active renin is due to both the enhancement of the release of renin from the kidney and the increase in the activation of inactive renin, and vice versa.
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3895577
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Recent several studies have shown that the insulin resistance exists in patients with myotonic dystrophy. Using in vitro radioreceptor assay with 125I-labeled insulin, we evaluated the binding of insulin to erythrocytes in patients with myotonic dystrophy. It was found that there was a decreased binding of insulin to erythrocytes in the patients with myotonic dystrophy. On quantitative analysis, this decrease in binding was found to be the result of a decrease in receptor affinity rather than receptor concentration. There was no evidence that the alteration in insulin receptor affinity was due to hyperinsulinemia. All of 7 patients with myotonic dystrophy also were shown to have an excessive response of endogenous insulin to a glucose challenge. No circulating antibody to insulin was found. These data suggest that a decrease in affinity of insulin receptors may, in part, cause insulin resistance and a compensatory elevation of the plasma insulin concentration in patients with myotonic dystrophy.
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3895576
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Immunoperoxidase localization of carcinoembryonic antigen (CEA) was performed on tissue sections of adenocarcinoma of endocervical and endometrial origin to clarify the criteria for their differentiation. Twenty-two (96%) of 23 endocervical and 32 (70%) of 46 endometrial adenocarcinomas revealed positive CEA immunostain. The extent of staining did not seem to correlate with the degree of differentiation in either kind of cancer. Among the positive cases, CEA staining was located over whole cytoplasm in 18 (80%) of 22 positive endocervical adenocarcinomas and on apical surface in 24 (75%) of 32 positive endometrial adenocarcinomas. The pattern of CEA distribution in endocervical adenocarcinoma of endometrioid type was not similar to that observed for primary endometrial adenocarcinoma.
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3895578
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The nature of amygdaloid kindled seizures was studied in adult rats which were intoxicated with lead starting in neonatal life. Lactating females were exposed to lead via the drinking water (0.25% lead acetate) and the litters were continued on this level of lead after weaning at 27 days of age. When compared to controls, levels of lead in the blood and brain were significantly higher in lead-exposed rats, both at the time of weaning as well as postkindling, beyond 150 days of age. Parameters relating to amygdaloid kindled seizures, including the rate of kindling, seizure latency and seizure threshold were not significantly different in lead-treated rats than in controls. However, duration of behavioral seizures and afterdischarges was significantly longer in rats exposed to lead. Our data suggest that, although lead intoxication starting in neonatal life does not appear to affect the susceptibility to development of amygdaloid kindled seizures, it may enhance seizure severity in this model of epileptogenesis.
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3895581
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An inhibitory effect of Bothrops castelnaudi venom was observed on the following systems: prothrombin time, activated partial thromboplastin time, thrombin time, thromboplastin generation time, activation of factor X by Russell's viper venom and Russell's viper venom activated factor X (factor Xa). This effect did not require previous incubation and was prevented by the addition of Bothrops-antivenom. The prolonged activated partial thromboplastin time was not shortened by increased phospholipid concentration (0.5-10 mg/ml), suggesting that the inhibitory effect is not due to an anti-phospholipid activity. No significant fibrinogenolytic activity was detected upon incubation of human fibrinogen with the venom, since physiological levels of thrombin-clottable material were still present. Compared to Bothrops jararaca venom, the proteolytic activity on casein and on azocoll was very low. Thrombin-induced clots of human plasma and fibrinogen were not lysed by the venom within 24 hr. The results indicate that the anticoagulant effect of Bothrops castelnaudi venom is exerted at least at two levels of the blood coagulation mechanism: (1) before prothrombin activation, by inhibiting factor X-activation and factor Xa activity; (2) by direct action on thrombin.
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3895579
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A sensitive radioimmunoassay for the detection of botulinum toxin, produced by Clostridium botulinum, was developed. This employs homogeneous botulinum neurotoxin type A and its 125I-labelled derivative of high specific radioactivity, rather than its complex with haemagglutinin as used hitherto. The sensitivity of the assay is 1 ng of neurotoxin per ml, which is equivalent to 80 LD50 units (half-lethal doses) in mice. Neurotoxin and its complex with haemagglutinin were measurable with equal sensitivity when using antibodies against botulinum neurotoxin type A. Specificity of the assay was demonstrated by the lack of response to type B and E botulinum toxins and to heat-inactivated botulinum toxin or extracts of Clostridium sporogenes strain BL46, which contains many surface antigenic determinants common to Clostridium botulinum. Using appropriate conditions, neurotoxin added to fish extract could be quantified accurately, proportionality being observed between the amounts of standard toxin added. In addition, the amounts of toxin species produced by culturing Clostridium botulinum in canned fish was measurable; the values obtained were comparable to those observed by the mouse bioassay. Moreover, the fish samples gave a dose-response curve in the competition radioimmunoassay which was paralleled by the response of botulinum neurotoxin standards. This assay offers the most sensitive, reliable immunological method available for the quantitation of molecular forms of botulinum toxin. As the technique can be used with unpurified fish extracts, it should be widely applicable to different types of samples contaminated with botulinum toxin; furthermore, the clinical diagnosis of human botulism could be substantiated with this method.
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3895580
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Haemorrhagic factor HF2 and bothropasin, two metalloproteins isolated from the venom of Bothrops jararaca, caused haemorrhage followed by myonecrosis and arterial necrosis after i.m. injection in mice. The effects of HF2 were qualitatively similar to those of bothropasin and crude B. jararaca venom, but its potency was about 20 times higher. The haemorrhagic and necrotizing actions of these components are unrelated to their proteolytic activity on casein.
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3895582
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Proteinase activities have been determined photometrically in 25 different Crotalidae and Viperidae snake venoms by using five different chromogenic proteinase substrates. The activity profiles obtained by listing the identity numbers of substrates hydrolyzed by the venoms in a decreasing potency order remained quite stable within a given snake population. Submission of a venom to various physical and chemical treatments did not alter its activity profile. It is therefore concluded that this simple method of determining proteinase activities could be of help in snake venom characterization, as well as in studying the influence of metallic ions and inhibitors of snake venom proteinases.
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3895583
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The structure of the unique 'red tide' dinoflagellate neurotoxin, brevetoxin-B is presented and the experimental data supporting the chemical structure is discussed. A brief account of the other brevetoxins and their structural relationships is also presented. A biosynthetic scheme for the natural formation of the brevetoxin skeleton is proposed. Studies of the most toxic of the three pure brevetoxins, brevetoxin-A, indicate a skeleton differing from that of brevetoxin-B.
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3895584
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A simple technique has been developed to quantitate the gastrin cells (G-cells) from the pyloric antrum of the rat. The antrum was digested in pronase to suspend the epithelial cells. This cell suspension was counted and pelleted. The pellet was embedded in paraffin, sectioned, then labeled using the indirect immunofluorescence technique specific for gastrin. The percentage of G-cells was determined from photographs of fluorescing sections and total G-cell numbers were determined by relating these data to total epithelial cell counts. In 14 rats the average G-cell population totaled 1.03 +/- 0.21 X 10(5) G-cells/antrum. The technique is simple, time-saving and avoids the uncertainties inherent in previous procedures for the estimation of G-cell numbers.
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3895585
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A method for the electron irradiation of the body surface is presented which can easily be applied and standardized. The patient is placed in prone and supine position on the normal irradiation table. Contrary to many other methods, this proceeding is especially comfortable for the patient.
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3895586
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Male Sprague Dawley rats were continuously irradiated at a dose-rate of either 5 or 7 cGy/day, up to a total dose of 900 cGy. Changes in spermatogenesis with irradiation and the recovery of the testis during 33 weeks after irradiation were studied. No clear dose-rate effect with testicular weight occurred. During the irradiation time, increased dose and dose-rate induced a decrease in A spermatogonia and preleptotene spermatocyte number. In our experimental conditions germ cell production did not plateau, as shown by the increasing number of tubular cross sections devoid of germ cells beyond 500 cGy. The recovery of seminiferous epithelium occurred essentially within nine weeks. It was not dose-rate dependent and was still incomplete after 33 weeks. This lack of recovery might be due to limited compensatory division ability of the stem cells. Clusters of Sertoli cells were observed in the lumen of the seminiferous tubules; impaired function of these cells could also prevent the complete recovery of the seminiferous epithelium. By 16 weeks after the end of irradiation 67% of 5 cGy/day irradiated rats and 34% of 7 cGy/day irradiated rats recovered fertility.
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3895587
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C57BL++ mice were either whole body X-irradiated with a dose of 200 R or, 15 minutes before X-irradiation injected with AET, MEA, or 5-HT, in a dose of 40 mg/kg of body weight, on the first day of gestation. Uterine contents were examined on the nineteenth day of pregnancy. The number of corpora lutea was assumed as 100% and the percentage values of live and dead foetuses, resorptions, and non-implanted embryos were calculated. The percentage ratio of females with live foetuses in the uterus, in relation to the total number of those with a vaginal plug was also determined. X-irradiation of pregnant mice influenced the embryonic survival. As compared with controls, in only X-irradiated mice a lower percentage value of live foetuses and higher percentage values of non-implanted embryos and resorptions were found. One dead foetus was only observed in X-irradiated females. Percentage value of X-irradiated females with live foetuses was lower than that of control ones. High mortality of embryos occurred more often before than after the implantation of blastocysts. The percentage value of non-implanted embryos was higher than that of resorptions. AET, MEA, and 5-HT when injected to mice before their X-irradiation acted as radioprotectors. The strongest radioprotective effect was obtained following AET administration, intermediate after 5-HT treatment and the weakest one when MEA was injected.
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