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71.
Sidhu P Garg ML Morgenstern P Vogt J Butz T Dhawan DK 《Biological trace element research》2004,102(1-3):161-172
This study was designed to determine the protective effects of zinc on the hepatotoxicity induced by nickel in rats. Female Sprague-Dawley (SD) rats received either nickel sulfate alone in the dose of 800 mg/L nickel in drinking water, zinc sulfate alone in the dose of 227 mg/L zinc in drinking water, and nickel plus zinc or drinking water alone for a total duration of 8 wk. The effects of different treatments were studied on activities of rat liver marker enzymes like alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferases (AST) and on the status of essential elements in rat liver. The study revealed a significant increase in the activities of enzymes ALP and ALT in rats subjected to nickel treatment. Interestingly, zinc supplementation to rats treated with nickel brought back the raised activities of these enzymes to within normal limits. Further, the levels of elements in liver that include zinc, copper, selenium, and potassium were found to be significantly suppressed following nickel treatment, whereas the levels of iron and sulfur were elevated. However, zinc treatment alone did not cause any appreciable change in the concentration of these elements. To the contrary, when zinc was given to nickel-treated rats, the concentrations of zinc, copper, potassium, and phosphorus were not significantly different from that of normal controls, whereas the levels of iron, selenium, and sulfur were improved in comparison to nickel-treated rats but were not within the normal limits. The present study concludes that zinc has the ability to maintain the levels of hepatic elements and has bearing in regulating the liver functions by maintaining the activities of marker enzymes in conditions of nickel toxicity. 相似文献
72.
The characteristic feature of visceral leishmaniasis (VL) is the profound impairment of immune system of the infected host, which contributes significantly to the partial success of antileishmanial chemotherapy. Since in VL, cure is the combinatorial effect of drug and immune status of the host, the rationale approach towards antileishmanial chemotherapy would be to potentiate the immune functioning of the host to extract desired results. Towards this direction several rationally designed analogues of human beta-casein fragment (54-59) were evaluated for their ability to stimulate the non-specific resistance in hamsters against Leishmania donovani infection. By virtue of being derived from the food protein casein derivatives may be devoid of unwanted side effects associated with the substances of microbial origin, e.g. muramyl dipeptide (MDP). Out of this one peptide Val-Glu-Gly-Ile-Pro-Tyr (compound 89/215) had been reported to have such activity. In this communication, the prophylactic and therapeutic efficacy of the peptide along with its natural sequence has been evaluated in detail against experimental VL in hamsters. Their use as an adjunct to chemotherapy was also explored. Human beta-casein fragment, compound 89/215 and MDP were tested in vivo at various dose levels wherein compound 89/215 showed superiority over MDP at 3 mg/kg x 2 given intraperitoneally (i.p.). Compound 89/215 sensitized peritoneal macrophages acquired considerable resistance and only 24% of the cells were found infected in comparison to control peritoneal macrophages where 76.4% of the cells were found infected. Similarly, the efficacy of sodium antimony gluconate (SAG) in hamsters pretreated with compound 89/215 enhanced significantly (P < 0.001). This peptide also exhibited considerably good therapeutic efficacy when evaluated either alone or in combination with SAG in established infection of L. donovani. 相似文献
73.
Background
Patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) commonly require hospitalization and admission to intensive care unit (ICU). It is useful to identify patients at the time of admission who are likely to have poor outcome. This study was carried out to define the predictors of mortality in patients with acute exacerbation of COPD and to device a scoring system using the baseline physiological variables for prognosticating these patients.Methods
Eighty-two patients with acute respiratory failure secondary to COPD admitted to medical ICU over a one-year period were included. Clinical and demographic profile at the time of admission to ICU including APACHE II score and Glasgow coma scale were recorded at the time of admission to ICU. In addition, acid base disorders, renal functions, liver functions and serum albumin, were recorded at the time of presentation. Primary outcome measure was hospital mortality.Results
Invasive ventilation was required in 69 patients (84.1%). Fifty-two patients survived to hospital discharge (63.4%). APACHE II score at the time of admission to ICU {odds ratio (95 % CI): 1.32 (1.138–1.532); p < 0.001} and serum albumin (done within 24 hours of admission) {odds ratio (95 % CI): 0.114 (0.03-0.432); p = 0.001}. An equation, constructed using the adjusted odds ratio for the two parameters, had an area under the ROC curve of 91.3%. For the choice of cut-off, sensitivity, specificity, positive and negative predictive value for predicting outcome was 90%, 86.5%, 79.4% and 93.7%.Conclusion
APACHE II score at admission and SA levels with in 24 hrs after admission are independent predictors of mortality for patients with COPD admitted to ICU. The equation derived from these two parameters is useful for predicting outcome of these patients. 相似文献74.
Lung cancer is the number one cause of cancer death; however, no specific serum biomarker is available till date for detection of early lung cancer. Despite good initial response to chemotherapy, small-cell lung cancer (SCLC) has a poor prognosis. Therefore, it is important to identify molecular markers that might influence survival and may serve as potential therapeutic targets. The review aims to summarize the current knowledge of serum biomarkers in SCLC to improve diagnostic efficiency in the detection of tumor progression in lung cancer. The current knowledge on the known serum cytokines and tumor biomarkers of SCLC is emphasized. Recent findings in the search for novel diagnostic and therapeutic molecular markers using the emerging genomic technology for detecting lung cancer are also described. It is believed that implementing these new research techniques will facilitate and improve early detection, prognostication and better treatment of SCLC. 相似文献
75.
76.
Work induced stress led to decreased cholesterol and fluctuating triglyceride levels in gastrocnemius and pectoralis muscles in rats. But the drug (clenbuterol, 2 mg kg(-1) day(-1)) treatment increased cholesterol and triglyceride levels in both the muscles. However, heart showed decreased cholesterol and increased triglyceride level in the animals under work stress, but at the same time drug treatment led to a significant increase in levels of the two lipid fractions, inferring towards deleterious effect of the drug on heart. 相似文献
77.
A Bayesian framework for combining gene predictions 总被引:2,自引:0,他引:2
MOTIVATION: Gene identification and gene discovery in new genomic sequences is one of the most timely computational questions addressed by bioinformatics scientists. This computational research has resulted in several systems that have been used successfully in many whole-genome analysis projects. As the number of such systems grows the need for a rigorous way to combine the predictions becomes more essential. RESULTS: In this paper we provide a Bayesian network framework for combining gene predictions from multiple systems. The framework allows us to treat the problem as combining the advice of multiple experts. Previous work in the area used relatively simple ideas such as majority voting. We introduce, for the first time, the use of hidden input/output Markov models for combining gene predictions. We apply the framework to the analysis of the Adh region in Drosophila that has been carefully studied in the context of gene finding and used as a basis for the GASP competition. The main challenge in combination of gene prediction programs is the fact that the systems are relying on similar features such as cod on usage and as a result the predictions are often correlated. We show that our approach is promising to improve the prediction accuracy and provides a systematic and flexible framework for incorporating multiple sources of evidence into gene prediction systems. 相似文献
78.
AGenDA: homology-based gene prediction 总被引:2,自引:0,他引:2
Taher L Rinner O Garg S Sczyrba A Brudno M Batzoglou S Morgenstern B 《Bioinformatics (Oxford, England)》2003,19(12):1575-1577
We present a www server for homology-based gene prediction. The user enters a pair of evolutionary related genomic sequences, for example from human and mouse. Our software system uses CHAOS and DIALIGN to calculate an alignment of the input sequences and then searches for conserved splicing signals and start/stop codons around regions of local sequence similarity. This way, candidate exons are identified that are used, in turn, to calculate optimal gene models. The server returns the constructed gene model by email, together with a graphical representation of the underlying genomic alignment. 相似文献
79.
Kumar A Singh US Singh A Malik VS Garg GK 《Indian journal of experimental biology》2000,38(6):525-539
Karnal bunt of wheat, incited by a phytopathogen Tilletia indica (Syn. Neovossia indica) is a floret infecting disease. In the floral tissues fungus proliferates and produces massive amount of black spores. In smut fungi, belonging to order Ustilaginales, communication between cells is necessary to regulate growth, differentiation and monokaryotic to dikaryotic transition during pathogenic and sexual development. Neighbouring cells are able to communicate with each other by direct cell to cell contact through plasma membrane bound signaling molecules or through formation of gap junctions and alternatively through secretion of chemical signals if cells are some distance away. Current research efforts toward understanding of pathogenic and sexual development in phytopathogenic fungi, offer a number of opportunities. These include the analysis of molecular signal(s) for direct contribution of sexual interactions to ability of smut and bunt pathogens to cause disease. These efforts will provide not only to explore the mechanisms of pathogenesis, but also to enhance knowledge of basic cellular biology of an economically important group of fungi. 相似文献
80.
Indirect enzyme linked immunosorbent assays (ELISA) were developed using polyclonal antibodies against soluble cytoplasmic (SCA) and insoluble cell wall antigens (ICWA) for monitoring modulation of mycelial antigens during growth cycle of T. indica. With SCA, continuous decrease in ELISA reactivity was observed in maturing fungus cultures, suggesting that SCA were expressed predominantly during early vegetative phase and their decreasing role was apparent as the fungus matures possibly towards sporogenous mycelium. In case of ICWA, the reaction profile showed an increase up to exponential phase of growth probably due to increase in the cell division and branching of mycelium. But later, ICWA antibody reactivity was decreased which may be due to conversion of mycelial phase to sporogenous phase, a quiescent stage of growth. Characterization of changes in antigenic configuration during developmental cycle of Tilletia indica by these antibodies could prove to be useful in identification of developmentally related and virulence marker(s). 相似文献