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Metabolomics - Methanol utilization by bacteria is important for various industrial processes. Methylotrophic bacteria are taxonomically diverse and some species promote plant growth and induce...  相似文献   
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Breast cancer is the most common malignancy in women and a public health problem worldwide. Breast cancer is often accompanied by an inflammatory process characterized by the presence of proinflammatory cytokines such as tumor necrosis factor (TNF-α), which has important implications in the course of the disease. Inflammation has been described primarily as a favorable environment for tumor development. However, under certain conditions TNF-α can promote signals for activation, differentiation, survival or cell death, so the study of the variants of this cytokine, its receptors, the presence of polymorphisms and its implication in different phenotypes of breast cancer is necessary. Although the clinical application of TNF-α has been limited by its toxicity and side effects, preclinical and clinical studies have shown that these effects may partially be avoided via tumor-targeted delivery strategies. In this manner, TNF-α alone or combined with chemotherapy and radiotherapy can function as an adjuvant in the treatment of breast cancer.  相似文献   
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As a continuation of our previous work that turned toward the identification of antimycobacterial compounds with innovative structures, two series of pyrazole derivatives were synthesized by parallel solution-phase synthesis and were assayed as inhibitors of Mycobacterium tuberculosis (MTB), which is the causative agent of tuberculosis. One of these compounds showed high activity against MTB (MIC = 4 microg/mL). The newly synthesized pyrazoles were also computationally investigated to analyze their fit properties to the pharmacophoric model for antitubercular compounds previously built by us and to refine structure-activity relationship analysis.  相似文献   
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WNT signalling has a key role in early embryonic patterning through the regulation of cell fate decisions, tissue polarity and cell movements. In the nervous system, WNT signalling also regulates neuronal connectivity by controlling axon pathfinding, axon remodelling, dendrite morphogenesis and synapse formation. Studies, from invertebrates to mammals, have led to a considerable understanding of WNT signal transduction pathways. This knowledge provides a framework for the study of the mechanisms by which WNTs regulate diverse neuronal functions. Manipulation of the WNT pathways could provide new strategies for nerve regeneration and neuronal circuit modulation.  相似文献   
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In this paper the combined use of in vivo (13)C-nuclear magnetic resonance spectroscopy and mathematical modelling allowed the analysis of the response to ethanol stress in a wild-type strain of Saccharomyces cerevisiae, in terms of a reduced metabolic activity. The model developed succeeded in describing and interpreting the effects of increasing concentrations of exogenous ethanol. In particular, the ratio between the kinetic constants associated with ethanol production and glucose consumption gave the estimation of the metabolic yield of the processes in perfect agreement with experimental results.  相似文献   
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Abstract BALB/c mice were inoculated intraperitoneally either once only, or up to four times at weekly intervals, with viable Rickettsia rickettsii, Rickettsia conorii or the Israeli spotted fever group rickettsia. Sera collected one week after the last inoculation were tested for the presence of antibodies reactive with the above organisms by indirect fluorescent antibody testing and Western blot. With repeated inoculations there was a general progressive rise in homologous and heterologous immunofluorescence titers although the increase after the first inoculation was always the greatest. For each rickettsia, the homologous titers were higher than the heterologous titers. Western blots showed that the reactive antibodies were against rickettsial high molecular mass species specific protein antigens and homologous species-specific antibody reactions were detectable earlier than heterologous cross-reacting antibody reactions. Antibodies in mice sera did not react with the group specific lipopolysaccharide-like antigens of the rickettsiae although such reactivity was strong in Western blots with sera from patients suffering from acute Rickettsia conorii infections. Our findings suggest that the intraperitoneal route of inoculation of BALB/c mice can be used for the differentiation of spotted fever group rickettsiae.  相似文献   
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