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Background

Giardia duodenalis is one of the most important human enteric parasites throughout the world. Clinical symptoms of this parasite vary from asymptomatic infection to chronic diarrhea. Still it is not clear, whether different types of pathogenesis are due to different strains of organism or to variable host factors. The purpose of this study was to investigate possible correlation of clinical symptoms with assemblages among symptomatic and asymptomatic cases collected from southwest of Iran.

Methods

Fecal samples were collected from 100 symptomatic and asymptomatic cases, which were positive for G. duodenalis. The samples were subjected to semi-nested PCR and RFLP for gdh gene.

Results

Among symptomatic patients, 54% had mixed genotypes AII and BIII, 28% and 18% of samples indicated assemblages BIII and AII, respectively. In contrast, among asymptomatic cases, 64%, 26% and 10%samples had mixed genotypes, BIII and AII assemblages, respectively. Statistical analysis using Chi- Square test showed that there was no significant correlation between assemblage and clinical symptoms in current study.

Conclusion

High prevalence of mixed infection in both groups may affect this conclusion, therefore further study in more details are necessary to clarify these finding. Additionally, it is important to carry out investigations regarding human host factors as well.  相似文献   
94.

Background

The biotransformation of steroids by fungal biocatalysts has been recognized for many years. There are numerous fungi of the genus Aspergillus which have been shown to transform different steroid substances. The possibility of using filamentous fungi Aspergillus brasiliensis cells in the biotransformation of androsta-1,4-diene-3,17-dione, was evaluated.

Methods

The fungal strain was inoculated into the transformation medium which supplemented with androstadienedione as a substrate and fermentation continued for 5 days. The metabolites were extracted and isolated by thin layer chromatography. The structures of these metabolites were elucidated using 1H-NMR, broadband decoupled 13C-NMR, EI Mass and IR spectroscopies.

Results

The fermentation yielded one reduced product: 17β-hydroxyandrost-1,4-dien-3-one and two hydroxylated metabolites: 11α-hydroxyandrost-1,4-diene-3,17-dione and 12β-hydroxyandrost-1,4-diene-3,17-dione.

Conclusions

The results obtained in this study show that A. brasiliendsis could be considered as a biocatalyst for producing important derivatives from androstadienedione.  相似文献   
95.
Cardioprotection by remote ischaemic preconditioning   总被引:1,自引:0,他引:1  
Perioperative myocardial infarction is a leading cause of morbidity and mortality after major non-cardiac surgery. Pharmacological agents such as beta-blockers may reduce the risk but are associated with side-effects and may be contra-indicated in some patients. Basic scientific experiments and preliminary clinical trials in humans suggest that remote ischaemic preconditioning (RIPC), where brief ischaemia in one tissue confers resistance to subsequent sustained ischaemic insults in another tissue, may provide a simple, cost-effective means of reducing the risk of perioperative myocardial ischaemia. The Medline and Pubmed databases were searched for articles concerning RIPC. The mechanism may be humoral, neural, or a combination of both, and involves adenosine, opioids, bradykinins, protein kinase C, and K-ATP channels, although the precise end-effector remains unclear. Small randomized trials in humans undergoing major surgery suggest that RIPC induced by brief lower limb ischaemia significantly reduces myocardial injury. It may also reduce other ischaemic complications of surgery and anaesthesia. Small studies provide some evidence that RIPC could reduce myocardial injury and other ischaemic complications of surgery. However, large-scale clinical trials to assess the effect of RIPC on mortality and morbidity are required before RIPC can be recommended for routine clinical use.  相似文献   
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Purpose: Antimicrobial activities of meropenem products on Klebsiella pneumoniae isolates were determined. Methods: 212 non-duplicated Klebsiella pneumoniae isolates were examined for in vitro meropenem susceptibility test by using the following disks, which were made from Meronem (AstraZeneca, UK), Exipenem (Exir, Iran) and Meroxan (DAANA, Iran) powders. MIC50 and MIC90 for meropenem antibiotics were determined.Results: Meronem had good activities against most isolates of Klebsiella pneumoniae, and only a few strains had a rather high MIC. Exipenem and Meroxan showed a similar activity with Meronem. Conclusion: Regarding the comparison of two internal generic meropenem products with the external Meronem product have shown that they are equivalents in terms of microbiological activity, as measured using the disk diffusion and MIC. In developing countries, we suggested preparing disks with antibiotic powders that can be an equivalent function in microbiological activity with standard disks. In addition, since it demonstrated significant antimicrobial activity against the Klebsiella pneumoniae. For use of Exipenem and Meroxan in vivo, it would be better to perform additional testing (activity against different species, stability etc.).  相似文献   
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OBJECTIVE: To examine the relation of dietary and physical activity (PA) patterns with the body mass index (BMI), and the associations between these patterns among children. METHODS: A representative sample of 21 111 school students aged 6-18 years was selected by multistage random cluster sampling from 23 provinces in the Islamic Republic of Iran. PA and dietary pattern were assessed by self-administered validated questionnaires. FINDINGS: Fruit and vegetables, dairy products and snacks (salty, fatty or sweet) had a similar consumption frequency of approximately twice a day. The type of fat most frequently consumed was hydrogenated solid fat (consumed by 73.8% of families). The PA level was significantly higher among boys than girls, in rural than in urban residents, and in intermediate students than high-school students. Among boys, the frequency of consumption of vegetables and plant proteins (R(2) = 0.46); and among girls, the frequency of consumption of dairy products and fruits, as well as high PA level had a significant inverse association with BMI (R(2) = 0.57). Among boys, the low frequency of consumption of fruits, the time spent on PA and the energy expenditure; and among girls, the time spent on PA and the energy expenditure, had significant relationships with overweight. When controlling for covariates, PA levels had significant relationships with the frequency of consumption of all food groups. CONCLUSION: Unhealthy lifestyles make Iranian young people prone to chronic diseases later in life. When examining their health benefits, the interrelationship of dietary and PA behaviours should be considered.  相似文献   
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