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Fulminant hepatic failure (FHF) is a condition with a sudden onset of necrosis followed by degeneration of hepatocytes, without any previously established liver disease, generally occurring within hours or days. FHF is associated with a wide spectrum of neuropsychiatric alterations ranging from stupor to coma, culminating in death. In the present study FHF was induced in rats by the administration of thioacetamide (TAA). Oxidative stress is thought to play a prominent role in the pathophysiology of cerebral changes during FHF leading to the assumption that antioxidants might offer protection. Hence, in the present study the protective effect of C-Phycocyanin (C-PC), a natural antioxidant, was evaluated on TAA-induced tissue damage. C-Phycocyanin was administered intraperitoneally twice at 24 h interval (50 mg/kg body weight) along with the hepatotoxin TAA (300 mg/kg body weight). The animals were sacrificed 18 h after the second injection of TAA treatment and various biochemical parameters were analysed in liver, serum and brain tissues. These studies revealed significant prevention of TAA-induced liver damage by C-PC, as evidenced by a) increase in survival rate; b) the prevention of leakage of liver enzymes (AAT and AST) and ammonia into serum; c) increase in prothrombin time and d) liver histopathology. Ultrastructural studies of astrocytes of different regions of brain clearly showed a decrease in edema after C-PC treatment. TAA-induced histopathological lesions in different regions of the brain namely cerebral cortex, cerebellum and pons medulla were significantly reduced by the co-administration of C-PC with TAA. Further C-PC treatment resulted in a) decrease in the levels of tryptophan and markers of lipid peroxidation and b) elevation in the activity levels of catalase, glutathione peroxidase in different regions of brain. These studies reveal the potential of C-PC in ameliorating TAA-induced hepatic encephalopathy by improving antioxidant defenses.  相似文献   
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The oral antihyperglycemic effect of the water and ethanolic extracts of the fruit-pulp of Eugenia jambolana (EJ) was investigated in alloxan-induced diabetic with fasting blood glucose between 120 and 250 mg/dl as well as severely diabetic rabbits (fasting blood glucose above 250 mg/dl). Water extract was found to be more effective than the ethanolic extract in reducing fasting blood glucose and improving blood glucose in glucose tolerance test. Chromatographic purification of the water extract yielded not only two hypoglycaemic fractions (F-III more active than F-IV) but indicated the presence of hyperglycemic compounds (F-I and F-II) also in the water extract of Eugenia jambolana fruits. When administered as a single dose of 25 mg/kg of body weight; F-III could reduce fasting blood glucose from 174.0 +/- 4.6 to 137.3 +/- 5.4 mg/dl in diabetic (21% fall) and from 266.0 +/- 5.4 to 202.2 +/- 5.2 mg/dl in severely diabetic rabbits (24% fall). After treatment of diabetic and severely diabetic rabbits daily once with 25mg/kg, body weight with F-III for 7 and 15 days, respectively, there was fall in fasting blood glucose (38% diabetic; 48% severely diabetic) and improvement in blood glucose during glucose tolerance test (48%) in diabetic rabbits. Further, there was increase in the plasma insulin levels in both diabetic (24.4%) and severely diabetic rabbits (26.3%). The in vitro studies with pancreatic islets showed that the insulin release was nearly two and half times more than that in untreated diabetic rabbits. The mechanism of action of FIII fraction appears to be both pancreatic by stimulating release of insulin and extra pancreatic by directly acting on the tissues.  相似文献   
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We report an unusual case of a recurrent fourth ventricular anaplastic ependymoma with prominent chondroid metaplasia in a 16-year-old male. On initial presentation, the patient had a WHO Grade II tumor. However, at recurrence 1 year later, the tumor progressed to WHO Grade III tumor with more cellularity, necrosis and brisk mitotic activity. Chondroid metaplasia was present in both the initial and recurrent tumors.  相似文献   
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There is no licensed vaccine available against Chlamydia trachomatis, the leading cause of bacterial sexually transmitted disease. We have found that intranasal immunization with recombinant chlamydial protease-like activity factor (CPAF) induces CD4(+) T-cell- and gamma interferon (IFN-gamma)-dependent protective immunity against murine genital chlamydial infection, thus making CPAF a viable vaccine candidate for further characterization. HLA-DR4 is the predominant allele involved in chlamydial antigen presentation to CD4(+) T cells in humans. We used engineered mice that lack endogenous major histocompatibility complex class II (MHC-II) alleles but express a human HLA allele (HLA-DR4 transgenic [tg] mice) to examine primary immune and CPAF-mediated responses against genital Chlamydia muridarum challenge. Upon primary bacterial exposure, HLA-DR4 tg mice developed Chlamydia-specific IFN-gamma and antibody production and resolved the infection within 30 days, similar to challenged conventional C57BL/6 animals. Moreover, C. muridarum-challenged HLA-DR4 tg mice exhibited CPAF-specific antibody and IFN-gamma production. Upon CPAF-plus-interleukin-12 (IL-12) vaccination, HLA-DR4 tg animals exhibited robust CPAF-specific IFN-gamma production and elevated titers of anti-CPAF total antibody and immunoglobulin G2a (IgG2a) and lower titers of IgG2b and IgG1 antibodies. HLA-DR4 tg and C57BL/6 mice vaccinated with CPAF plus IL-12 resolved the primary genital chlamydial infection significantly earlier than mock-immunized animals, whereas similarly vaccinated MHC class II-deficient mice displayed minimal antigen-specific immune responses and failed to resolve the infection even at 30 days postchallenge. Together, these results demonstrate the importance of human HLA-DR4 molecules in the recognition and presentation of CPAF epitopes, leading to the generation of protective antichlamydial immunity and making these mice a valuable model for mapping HLA-DR4-restricted chlamydial epitopes.  相似文献   
107.

Background  

The leaf juice or water decoction of Catharanthus roseus L. (Apocyanaceae) is used as a folk medicine for the treatment of diabetes all over the world. In the present investigation, the leaf juice of C. roseus has been evaluated for its hypoglycemic activity in normal and alloxan-induced diabetic rabbits.  相似文献   
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The Pseudomonas aeruginosa PA01 Gene Collection   总被引:1,自引:0,他引:1       下载免费PDF全文
Pseudomonas aeruginosa, a common inhabitant of soil and water, is an opportunistic pathogen of growing clinical relevance. Its genome, one of the largest among bacteria [5570 open reading frames (ORFs)] approaches that of simple eukaryotes. We have constructed a comprehensive gene collection for this organism utilizing the annotated genome of P. aeruginosa PA01 and a highly automated and laboratory information management system (LIMS)-supported production line. All the individual ORFs have been successfully PCR-amplified and cloned into a recombination-based cloning system. We have isolated and archived four independent isolates of each individual ORF. Full sequence analysis of the first isolate for one-third of the ORFs in the collection has been completed. We used two sets of genes from this repository for high-throughput expression and purification of recombinant proteins in different systems. The purified proteins have been used to set up biochemical and immunological assays directed towards characterization of histidine kinases and identification of bacterial proteins involved in the immune response of cystic fibrosis patients. This gene repository provides a powerful tool for proteome- and genome-scale research of this organism, and the strategies adopted to generate this repository serve as a model for building clone sets for other bacteria.  相似文献   
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