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101.
BioProtein is a single cell protein produced by a mixed methanotrophic and heterotrophic bacteria culture using natural gas as energy source, which has been approved for animal feed. BioProtein contains a large amount of nucleic acids making the product less suitable for human consumption, therefore, a nucleic acid reduced variant (NABP) has been developed by the manufacturer. The purpose of the present study was to establish the safety of NABP in a subchronic toxicity rat study. Groups of 10 male and 10 female Wistar rats were fed diets containing 0, 6, 12 or 24% NABP for 13 weeks. Feeding NABP induced a humoral immune response and proliferation of phagocytic cell lines, mainly macrophages. The humoral response involved induction of NABP specific IgM and IgG. The proliferation of phagocytic cells involved increase of the white blood cell count of all dosed female groups. Males showed the same tendency, although, not statistically significant (P=0.09). The subsets of cells identified as neutrophils and eosinophils were increased and lymphocytes decreased. The histopathological examination revealed histiocytosis and accumulation of foamy macrophages in the mesenteric lymph nodes, hyperplasia of Kupffer cells in the liver, increased granulopoiesis in spleen and bone marrow, and infiltration of lamina propria of the large intestine with eosinophilic granulocytes. The most consistent and pronounced changes were observed in the highest dose group, but even at the lowest dose level some of the changes were present. Accordingly, a no-observed-effect level could not be established based on this study.  相似文献   
102.
Cyclodextrin complexes of the natural compound curcumin were prepared in order to improve the water solubility and the hydrolytic and photochemical stability of the compound. Complex formation resulted in an increase in water solubility at pH 5 by a factor of at least 10(4). The hydrolytic stability of curcumin under alkaline conditions was strongly improved by complex formation, while the photodecomposition rate was increased compared to a curcumin solution in organic solvents. The cavity size and the charge and bulkiness of the cyclodextrin side-chains influenced the stability constant for complexation and the degradation rate of the curcumin molecule.  相似文献   
103.
OBJECTIVE: To elucidate how frequent weight-loss attempts are made, the methods used to achieve weight loss, and the extent to which the outcome is positive. RESEARCH METHODS AND PROCEDURES: Two independent interviews were conducted in 1992 and in 1998, each with 1200 randomly selected adult subjects. Each survey was designed to ensure an equal distribution of age, gender, and geographical regions in Denmark. RESULTS: The proportion of subjects having attempted weight loss did not change from 1992 to 1998, although the prevalence of overweight and obesity increased from 1992 (overweight, 30%; obesity, 6%) to 1998 (overweight, 35%; obesity, 8%). Almost twice as many women (61%) than men (32%) had attempted weight loss (p < 0.0001). Slimming occurred more often in subjects <50 years (51%) than >50 years (39%) (p < 0.0001), although overweight and obesity were more frequent in the elderly. Over-the-counter diet pills or meal replacements were associated with a negative outcome of slimming treatment (p < 0.0001). DISCUSSION: Approximately half of all adult Danes have attempted weight loss, particularly women and individuals <50 years. This finding is inconsistent with the fact that overweight and obesity are more prevalent in men and in individuals >50 years. Changes in habitual diet and increased physical activity are the most prevalent modes of slimming, whereas the use of over-the-counter diet pills or meal replacements has decreased from 1992 to 1998. This development may have a positive impact on future body- weight-management strategies.  相似文献   
104.
Treatment failures are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa when triple therapy including metronidazole is used. In patients with treatment failure and metronidazole-resistant H. pylori, a higher eradication rate for H. pylori was found after secondary treatment with bismuth/ranitidine in combination with antibiotics including metronidazole, compared with the same antibiotics combined with a standard dose of omeprazole. This agrees with our previous finding that bismuth was able to reduce the susceptibility of H. pylori to metronidazole. In this study, we have found that nizatidine, an H(2)-receptor antagonist, is also able to reduce the susceptibility of H. pylori to metronidazole in vitro, despite having no direct inhibitory effect on the growth of H. pylori. This agrees with earlier findings that compounds having the ability to reverse antibiotic resistance do not necessarily have an antibiotic or chemotherapeutic effect in the sense of growth inhibition. Therefore, it was decided to investigate the effect of nizatidine and omeprazole on the oxidative respiratory chain, as it is known that metronidazole is able to inhibit the activity of fumarate reductase of H. pylori. This enzyme is a key enzyme in the alternative respiratory chain under anaerobic conditions. Nizatidine was, in these preliminary experiments, found to inhibit fumarate reductase in a dose-dependent way, like metronidazole, whereas omeprazole had almost no effect on fumarate reductase. No other significant effects on the enzymes of the respiratory chain were found. The synergistic effect of nizatidine on metronidazole resistant H. pylori strains could be explained by the effect on fumarate reductase, whereas the effect of omeprazole is different and could be an inhibition of a proton pump in H. pylori. Reversal of antimicrobial resistance with the help of different non-antibiotics seems to be possible by using quite different compounds, and is therefore to be explained by different molecular mechanisms.  相似文献   
105.
106.
Postoperative cognitive dysfunction in middle-aged patients   总被引:19,自引:0,他引:19  
BACKGROUND: Postoperative cognitive dysfunction (POCD) after noncardiac surgery is strongly associated with increasing age in elderly patients; middle-aged patients (aged 40-60 yr) may be expected to have a lower incidence, although subjective complaints are frequent. METHODS: The authors compared the changes in neuropsychological test results at 1 week and 3 months in patients aged 40-60 yr, using a battery of neuropsychological tests, with those of age-matched control subjects using Z-score analysis. They assessed risk factors and associations of POCD with measures of subjective cognitive function, depression, and activities of daily living. RESULTS: At 7 days, cognitive dysfunction as defined was present in 19.2% (confidence interval [CI], 15.7-23.1) of the patients and in 4.0% (CI, 1.6-8.0) of control subjects (P < 0.001). After 3 months, the incidence was 6.2% (CI, 4.1-8.9) in patients and 4.1% (CI, 1.7-8.4) in control subjects (not significant). POCD at 7 days was associated with supplementary epidural analgesia and reported avoidance of alcohol consumption. At 3 months, 29% of patients had subjective symptoms of POCD, and this finding was associated with depression. Early POCD was associated with reports of lower activity scores at 3 months. CONCLUSIONS: Postoperative cognitive dysfunction occurs frequently but resolves by 3 months after surgery. It may be associated with decreased activity during this period. Subjective report overestimates the incidence of POCD. Patients may be helped by recognition that the problem is genuine and reassured that it is likely to be transient.  相似文献   
107.
108.
The long-term inhibition by strychnine of glycine receptor activity in neurons provokes the receptor's selective intracellular accumulation and disappearance from synapses. This could result either from a disruption of the postsynaptic anchoring of the receptor or from an arrest of its exocytic transport. In this study we combined biochemical and fluorescence microscopy analyses to determine on a short time scale the fate of the strychnine-inactivated glycine receptor. Quantification of the cellular content of receptor showed that the rapid accumulation depends on protein synthesis. Cell surface biotinylation of neurons demonstrated that strychnine did not accelerate the turnover rate of the receptor. Labeling of endosomes indicated that, in strychnine-treated cells, the accumulated receptor is not blocked in the endosomal transport pathway. Taken together, these results indicate that strychnine does not destabilize the postsynaptic receptor but triggers its disappearance from synapses by a nondegradative sequestration of newly synthesized molecules in a nonendocytic compartment.  相似文献   
109.
The immune reactivity implicated in the pathogenesis of Guillain-Barré syndrome (GBS) and related diseases, which occur following infection with specific strains of Campylobacter jejuni bearing sialylated lipopolysaccharide structures that cross-react with specific gangliosides, is consistent with provocation of inflammation via molecular mimicry. In this review, we have focused upon microbial characteristics and structures, the fine structure of the essential carbohydrate determinants, and the application of our proposed criteria, modified from those of Koch for causation of infectious and of Witebsky for autoimmune diseases, to the circumstance of infectious induction of autoimmune disorder.  相似文献   
110.
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