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1.
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Retinal microvascular endothelial dysfunction is thought to be of importance in the development of ocular vascular diseases....  相似文献   
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Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g., nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an alternative for treatment of symptomatic biliary leakage instead of immediate reoperation. Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation).  相似文献   
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Tuberculosis in seals is caused by a member of the Mycobacterium tuberculosis complex referred to as the 'seal bacillus'. Fluorescent amplified-fragment length polymorphism (FAFLP) analysis was applied to isolates from four Australian and six Argentinean seals and compared with FAFLP pattern for standard strains belonging to the M. tuberculosis complex. The FAFLP profiles derived from EcoRI/MseI restricted fragments of blind coded DNA samples differentiated the seal bacillus from other members of the M. tuberculosis complex. According to the phylogenetic analysis performed using FAFLP data, seal bacilli appear to have diverged significantly from other members of the M. tuberculosis complex. We describe the suitability of a panel of 19 highly polymorphic markers for rapid identification and comparative genomic analyses of the seal bacillus strains. It is likely that these bacilli got separated from the M. tuberculosis lineage as a result of different insertion deletion events occurring on a genome wide scale. Our analysis reveals that the seal bacillus and M. bovis are genetically related and therefore, might have originated from a common ancestor. Our data additionally support the hypothesis that seal bacillus occupies a unique taxonomic position within the M. tuberculosis complex.  相似文献   
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The host immune response to intracellular transgenes delivered by helper-dependent (HDV) vs. first generation (FGV) adenoviral vectors has been relatively unstudied. Previous studies showed short-term correction of bovine and murine argininosuccinate synthetase (ASS) deficiency after first generation adenoviral-mediated liver gene therapy. To determine whether the host adaptive immune response against the intracellular transgene human ASS (hASS) contributed to loss of gene expression in this setting, the same vector (FGV-CAG-hASS) was injected into Rag-/- (immunodeficient) mice. As in wild-type C57BL/6 (B6) mice, Rag-/- mice also showed significant loss of hASS expression and vector by week 4 post-injection, with concomitant elevation of liver enzymes and disruption of liver architecture. Therefore, direct toxicity due to vector rather than adaptive immune response against hASS primarily accounted for loss of expression with FGVs. In contrast to hASS, beta-galactosidase is strongly immunogenic and activates the host adaptive immune response. Loss of transgene expression was observed in B6 mice with either a FGV or a HDV expressing beta-galactosidase. However, the drop in gene expression observed with the HDV was primarily due to the adaptive immune response, since both beta-galactosidase expression and vector genome were sustained in immunodeficient mice treated with HDV. As expected, with weakly immunogenic hASS, vector genome and hASS expression were sustained with a HDV in spite of ubiquitous expression of the transgene. Therefore, viral gene expression is a primary determinant of intermediate and chronic toxicities at day 3 and week 4 post-injection. However, even in the absence of viral gene expression, strongly immunogenic intracellular transgenes can stimulate clearance of transduced hepatocytes.  相似文献   
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BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures.  相似文献   
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Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro.  相似文献   
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