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11.
The most common type of candidiasis involves mucosal sites such as the oral cavity, the gastrointestinal tract and the vagina. Among many of virulence factors, the production of secretory aspartyl proteinase (Sap) by Candida albicans (C. albicans) has gained much attention, and factors leading to Sap induction are thus under intense study. The aim of this study was to examine whether some microorganisms such as Lactobacillus, Gardnerella vaginalis (G. vaginalis), human immunodeficiency virus type-1 (HIV-1) and human herpes simplex virus type-2 (HSV-2) had any Sap inducing effect on C. albicans. Here we showed that among the microorganisms tested in vitro only HIV-1 induced Sap production from C. albicans.  相似文献   
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During monthly sampling from Lake Alada (Bolu, Turkey) between April 2003 and June 2004, nine ostracod taxa (Candona candida, Cypridopsis vidua, Darwinula stevensoni, Eucypris virens, Eucypris sp., Heterocypris sp., Limnocythere inopinata, Physocypria kraepelini, and Tonnacypris lutaria) were recorded from seven stations. Physocypria kraepelini was commonly found in the lake while the others were recorded in particular months. UPGMA analyses clustered three groups based on their occurrence. Accordingly, the occurrence of species (C. candida, E. virens, and T. lutaria) was positive and significantly related to each other. Two species, P. kraepelini and D. stevensoni, showed a significant positive relationship with electrical conductivity. A significant negative correlation was found between the occurrence of P. kraepelini and dissolved oxygen, while there was a significant positive correlation between the occurrence of P. kraepelini and turbidity. About 76% of the relationship between species and environmental factors was explained by the first two axes of canonical correspondence analyses (CCA). Temperature and dissolved oxygen were the two most important influences on the species assemblages. All species showed different but high optima and tolerance ranges, corresponding with their cosmopolitan characteristics. These responses may be related to unstable ecological characteristics of Lake Alada, which is often subjected to human activity.  相似文献   
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We aimed to investigate the association between manganese superoxide dismutase (MnSOD) Ala-9-Val gene polymorphism and the initiation and/or progression of prostate cancer (PCa) as well as to evaluate its potential interactions with advanced age and smoking status. MnSOD Ala-9-Val gene polymorphism was carried out in 134 (mean age 64.1 ± 7.48) PCa patients and 159 (mean age 62.5 ± 7.53) healthy controls with serum prostate specific antigen (PSA) levels (<4 ng/ml) and normal digital rectal examination (DRE) findings in this prospectively designed study. PCa patients were classified as low stage disease (T1 or T2 and N0M0 stages) and high stage disease (T3 or T4 and N0M0 or N1 or M1 stages). Genotypes for MnSOD Ala-9-Val gene polymorphism were identified by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFPL). Despite lack of association between different genotypes of MnSOD Ala-9-Val gene polymorphism and the presence of PCa, patients with Ala/Ala genotype were at an increased risk of high stage disease compared with those with the Val/Val genotype [odds ratio (OR), 3.77; 95% CI, 1.30–10.94; P = 0.012]. However, no significant difference was observed in the distribution of each genotype among PCa patients, with respect to tumor grade. On the other hand, smoking status and aging did not seem to change the association between genotypes and PCa risk. Ala/Ala genotype of MnSOD polymorphism may have an effect on adverse features of PCa such as high stage disease.  相似文献   
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Insects engage in symbiotic associations with a large diversity of beneficial microorganisms. While the majority of well-studied symbioses have a nutritional basis, several cases are known in which bacteria protect their host from pathogen infestation. Solitary wasps of the genera Philanthus and Trachypus (beewolves; Hymenoptera, Crabronidae) cultivate the actinomycete "Candidatus Streptomyces philanthi" in specialized antennal gland reservoirs. The symbionts are transferred to the larval cocoon, where they provide protection against pathogenic fungi by producing at least nine different antibiotics. Here we investigated the closest relatives of Philanthus and Trachypus, the rare genus Philanthinus, for the presence of antennal gland reservoirs and symbiotic streptomycetes. Molecular analyses identified "Ca. Streptomyces philanthi" in reservoirs of Philanthinus quattuordecimpunctatus. Phylogenies based on the 16S rRNA gene suggest that P. quattuordecimpunctatus may have acquired "Ca. Streptomyces philanthi" by horizontal transfer from other beewolf species. In histological sections and three-dimensional reconstructions, the antennal gland reservoirs were found to occupy six antennal segments (as opposed to only five in Philanthus and Trachypus) and to be structurally less complex than those of the evolutionarily more derived genera of beewolves. The presence of "Ca. Streptomyces philanthi" in antennal glands of Philanthinus indicates that the symbiosis between beewolves and Streptomyces bacteria is much older than previously thought. It probably evolved along the branch leading to the monophyletic tribe Philanthini, as it seems to be confined to the genera Philanthus, Trachypus, and Philanthinus, which together comprise 172 described species of solitary wasps.  相似文献   
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Objective: The purpose of this study was to examine the possible effects of a gastrointestinal lipase inhibitor “Orlistat (Xenical)” on the intestinal absorption of oxalate and thereby on the urinary levels of oxalate excretion in overweight patients. Methods and Procedures: Long‐term follow‐up data of 95 cases (57 men, 38 women; M/W= 1.5) were documented. Patients were randomly assigned into two groups. While the patients in group I (n = 55) were treated with orlistat (Xenical) for 6 months, patients in group II (n = 40) received no specific medication. Calcium, oxalate, and citrate levels were determined in a 24‐h urine collection from each patient. To evaluate the significance in the groups as well as the differences between the two groups, ANOVA test was performed and the results were given as mean ± s.d. Results: Comparative evaluation of urinary oxalate levels during 3‐month follow‐up clearly showed that urinary oxalate excretion significantly increased in 34/55 patients (61.8%) in the first group (P < 0.05). Of these 34 patients, 30 (88.2%) continued to have increased urinary oxalate excretion during 6‐month follow‐up (P = 0.001). However, our data did not show any significant effect of this medication on urinary citrate and calcium levels during 3‐ and 6‐month follow‐up evaluation (P = 0.05). Discussion: Our results suggest that increased intestinal absorption of dietary oxalate due to this type of medication in obese patients could make a substantial contribution to urinary oxalate excretion and may increase the risk of stone formation.  相似文献   
16.
Two pathogenic microorganisms Escherichia coli O157:H7 and Staphylococcus aureus, suspended in peptone solution (0.1% w/v) were treated with 12, 14, 16 and 20 kV/cm electric field strengths with different pulse numbers up to 60 pulses. Pulsed electric field (PEF) treatment at 20 kV/cm with 60 pulses provided nearly 2 log reduction in viable cell counts of E. coli O157:H7 and S. aureus. S. aureus cells were slightly more resistant than E.coli O157:H7 cells. The results related to the effect of initial cell concentration of E. coli O157:H7 on the PEF inactivation showed that more inactivation was obtained by decreasing initial cell concentration. Any possible injury by PEF was also investigated after applying 20 kV/cm electric field to the microorganisms. As a result, it was determined that there was 35.92 to 43.36% injury in E. coli O157:H7 cells, and 17.26 to 30.86% injury in S. aureus cells depending on pulse number. The inactivation results were also described by a kinetic model.  相似文献   
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A sensitive and specific assay was developed to detect and biological control of bacterial leaf spot of pumpkin, Xanthomonas cucurbitae was identified on the basis of the morphological, biochemical and molecular assay. The antibiotic sensitivity of the isolate showed that, Carbenicillin revealed highest antibacterial activity with 29 ± 0.00 mm zone of inhibition against isolated bacterial strain. Isolated bacterial strains from soil were also identified by biochemical and molecular characterisation. By analysing morphological and biochemical characteristics and 16S rDNA of three bacterial strains isolated from soil was matched 96% with Bacillus subtilis, 98% with Bacillus brevis and 97% with Pseudomonas fluorescens strain. They were subjected to the antagonistic activity against Xanthomonas cucurbitae by disc diffusion method. Among them, B. subtilis showed significant positive antagonistic activity with 17.0 ± 0.28 mm zone of inhibition against Xanthomonas cucurbitae. The presence of DNA sequence related to the hrpD gene successfully amplified in some isolates of Xanthomonas cucurbitae.  相似文献   
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