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Type I diabetes mellitus (insulin-dependent DM = IDDM) is a chronic disease characterized by specific destruction of pancreatic beta cells, resulting in an absolute lack of insulin. Immune mechanisms, genetic susceptibility, and environmental factors are all implicated in the pathogenesis of Type 1 diabetes. This study was aimed at determining the efficiency of cytokines, natural killer (NK) cells in the pathophysiology of IDDM. Therefore, we evaluated the plasma levels of cytokines by specific enzyme-linked immunosorbent assay (ELISA) and the cytotoxicity activity of NK cells by anti-candididal index in rats with type I diabetes. We found that the cytotoxicity activity of NK cells in IDDM groups significantly decreased compared to the control groups. The levels of interferon-gamma (IFN-gamma) in IDDM groups were slightly higher than in healthy controls. These results indicate that the changes of T H1 type cytokines such as IFN-gamma and NK cell activity can play a role in the etiology of IDDM. The data may provide new strategies for the treatment of IDDM.  相似文献   
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Slime and proteinase activity of 54 strains consisting of 19 Candida parapsilosis and 35 C. albicans strains isolated from blood samples were investigated in this study. Ketoconazole, amphothericin B, and fluconazole susceptibility of Candida species were compared with slime production and proteinase activity of these species. For both Candida species, no correlation was detected between the slime activity and minimum inhibitory concentration (MIC) values of the three antifungal agents. For both Candida species no correlation was detected between the proteinase activity and the MIC values of amphothericin B, and fluconazole however, statistically significant difference, was determined between the proteinase activity and MIC values of ketoconazole (p = 0.007). Slime production was determined by using modified Christensen macrotube method and proteinase activity was measured by the method of Staib. Antifungal susceptibility was determined through the guidelines of National Committee for Laboratory Standards (NCCLS M27-A).  相似文献   
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Sternbergia fischeriana is an endangered geophyte and therefore in vitro micropropagation of this plant will have great importance for germplasm conservation and commercial production. Bulb scale and immature embryo explants of S. fischeriana were cultured on different nutrient media supplemented with various concentrations of plant growth regulators. Immature embryos produced higher number of bulblets than bulb scales. Large numbers of bulblets were regenerated (over 80 bulblets/explants) from immature embryos on Murashige and Skoog (MS) medium supplemented with 4 mg l–1 6-benzylaminopurine (BA) and 0.25 mg l–1 -naphthaleneacetic (NAA) or 2 mg l–12,4-dichlorophenoxyacetic acid (2,4-D) after 14 months of culture initiation. Regenerated bulblets were kept at 5 °C for 5 weeks and then transplanted to a potting mixture.  相似文献   
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Kainic acid (KA) initiates neuronal injury and death by inducing oxidative stress and nitric oxide release from various regions of the brain. It was recently shown that melatonin has free radical-scavenging action and may protect against kainate-induced toxicity. In order to assess the possible supportive effect of melatonin treatment in KA-induced injury in the rat brain cortex, we determined malondialdehyde (MDA) levels as an index of lipid peroxidation, and assessed the activities of catalase (CAT) and superoxide dismutase (SOD) and the levels of nitrite/nitrate 35 male rats were divided into five groups, each receiving a different intraperitoneal treatment: saline solution (0.2 ml), kainic acid (15 mg/kg), melatonin (20 mg/kg), KA then melatonin (each as above, 15 min apart), or melatonin then KA (each as above, 30 min apart). Administration of KA caused an about five-fold increase in the catalase activity and an increase in the SOD activity in the cortex relative to the activities for the controls. Treatment with melatonin 15 min after KA injection kept malondialdehyde levels and catalase and superoxide dismutase activities at the normal levels, and led to an increase in the levels of nitrite/nitrate. Our data suggests that melatonin treatment following KA administration has a protective effect on antioxidant enzyme activities and thus supports the role of melatonin and oxidative stress in the regulation of antioxidative enzyme activity.  相似文献   
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Thioredoxin (Trx) is a multifunctional protein with a redox-active disulfide/dithiol in the active site. Thioredoxin, with its redox-regulating and reactive oxygen species (ROS) scavenging activities, plays several important biologic roles both in intracellular and extracellular compartments. The purpose of this report was to quantify the relative expression of Trx in rat hippocampus following an oxidative stress-involving treatment such as kainic acid (KA) using real-time PCR and the 2(-DeltaDeltaC(T)) method. The relative changes in expression of Trx mRNA in KA-treated and control animals were significantly different as 2.02 +/- 0.77 and 1.0 +/- 0.26, respectively (P<0.05). Minimum and maximum n-fold changes in Trx expression in KA-treated and control animals were determined as (1.4-5.2) and (0.8-1.3), respectively. Thus, real-time PCR and the 2(-DeltaDeltaC(T)) method for data analysis from real-time PCR were found to be an accurate and sensitive method for quantifying Trx mRNA levels.  相似文献   
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Toluene is used widely, not only in industry, but also in households where toluene exposure and abuse can occur. To estimate the genotoxic risk of toluene exposure, DNA damage was determined in peripheral lymphocytes of 20 glue sniffers and 20 age-matched controls by use of the alkaline comet assay. Urinary hippuric acid and o-cresol excretion rates, which are used as a marker for toluene exposure, were also measured in sniffers and compared with historical control values. The increase in genetic damage in sniffers was statistically significant as compared to control subjects (P<0.0001). The mean values of the hippuric acid and o-cresol excretion rate for glue sniffers was 73- and 1582-fold higher, respectively, than in controls and confirms the putative exposure. Education of the general public and efforts to keep adolescents away from volatile solvent-based products, which may lead to a desire of sniffing in the future, would be advisable.  相似文献   
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Objective: The aim of this study was to investigate effect of loss weight on P wave dispersion in obese subjects. Research Methods and Procedures: After a 12‐week weight loss program (diet and medical therapy), a total of 30 (24 women and six men) obese subjects who had lost at least 10% of their original weight were included in the present study. All subjects underwent a routine standard 12‐lead surface electrocardiogram. Electrocardiograms were transferred to a personal computer by a scanner and then magnified 400 times by Adobe Photoshop software (Adobe Systems, Mountain View, CA). P wave dispersion, which is also defined as the difference between the maximum P wave duration and the minimum P wave duration, was also calculated. Results: After a 12‐week weight loss program, BMI (p < 0.001), maximum P wave duration (p < 0.001), and P wave dispersion (p < 0.001) significantly decreased. The mean percentage of weight loss was 13% (10% to 20.3%). The decrease in the level of P wave dispersion (21 ± 10 and 7 ± 12 ms, p < 0.002) was more prominent in Group II (≥12% loss of their original weight) than Group I (<12% loss of their original weight) after the weight loss program. A statistically significant correlation between decrease in the level of P wave dispersion and percentage of weight loss was found (r = 0.624, p < 0.001). Discussion: Substantial weight loss in obese subjects is associated with a decrease of P wave duration and dispersion. Therefore, these observations suggest that substantial weight loss is associated with improvement in atrial repolarization abnormalities in obese subjects.  相似文献   
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