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The induction by gamma radiation of reproductive death in cultured cells derived from a rat ureter carcinoma (RUC-2) and from Chinese-hamster lung tissue (CH-V79) was shown to be enhanced by hyperthermic treatments at 41, 43 and 45 degrees C. The degree of enhancement was found to depend on the line of cells studied, the temperature employed and the level of damage considered. The influence of accumulating sublethal damage was decreased by hyperthermia, and the final slope of the radiation survival curve was increased. The degree of enhancement of lethal damage was found to depend on the time interval between the heat treatment and irradiation, especially at 41 degrees C.  相似文献   
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Singh  Ashutosh  Singh  Rahul Soloman  Sarma  Phulen  Batra  Gitika  Joshi  Rupa  Kaur  Hardeep  Sharma  Amit Raj  Prakash  Ajay  Medhi  Bikash 《中国病毒学》2020,35(3):290-304
The recent outbreak of coronavirus disease(COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has already affected a large population of the world. SARS-CoV-2 belongs to the same family of severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERSCoV). COVID-19 has a complex pathology involving severe acute respiratory infection, hyper-immune response, and coagulopathy. At present, there is no therapeutic drug or vaccine approved for the disease. There is an urgent need for an ideal animal model that can reflect clinical symptoms and underlying etiopathogenesis similar to COVID-19 patients which can be further used for evaluation of underlying mechanisms, potential vaccines, and therapeutic strategies. The current review provides a paramount insight into the available animal models of SARS-CoV-2, SARS-CoV, and MERS-CoV for the management of the diseases.  相似文献   
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In our previous study, we demonstrated the potential of monocrotophos (MCP), an organophosphorus insecticide (OPI), to induce glucose intolerance, insulin resistance (IR), and dyslipidemia with hyperinsulinemia in rats after chronic exposure. As hyperinsulinemia is likely to exert an impact on hepatic lipid metabolism, we carried out this study to establish the effect of chronic MCP exposure (0.9 and 1.8 mg/kg/day for 180 days) on hepatic lipid metabolism in rats. The state of IR induced by MCP in rats was associated with an increase in the liver lipid content (triglyceride and cholesterol) and expression levels of sterol regulatory element‐binding proteins, PPARγ, acetyl‐CoA carboxylase, and fatty acid synthase in the liver. Similarly, activities of key enzymes (acetyl‐COA carboxylase, fatty acid synthase, lipin 1, malic enzyme, glucose‐6‐phosphate dehydrogenase, and glycerol‐3‐phosphate dehydrogenase), which regulate lipogenesis, were enhanced in livers of pesticide‐treated rats. A strong correlation was observed between insulin levels, hepatic lipid content, and plasma lipid profile in treated rats. Our study suggests that long‐term exposure to OPIs not only has a propensity to induce a state of hyperinsulinemic IR, but it is also associated with augmented hepatic lipogenesis, which may explain dyslipidemia induced by chronic exposure to MCP.  相似文献   
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Most signal transduction pathways in humans are regulated by protein kinases through phosphorylation of their protein substrates. Typical eukaryotic protein kinases are of two major types: those that phosphorylate‐specific sequences containing tyrosine (~90 kinases) and those that phosphorylate either serine or threonine (~395 kinases). The highly conserved catalytic domain of protein kinases comprises a smaller N lobe and a larger C lobe separated by a cleft region lined by the activation loop. Prior studies find that protein tyrosine kinases recognize peptide substrates by binding the polypeptide chain along the C‐lobe on one side of the activation loop, while serine/threonine kinases bind their substrates in the cleft and on the side of the activation loop opposite to that of the tyrosine kinases. Substrate binding structural studies have been limited to four families of the tyrosine kinase group, and did not include Src tyrosine kinases. We examined peptide‐substrate binding to Src using paramagnetic‐relaxation‐enhancement NMR combined with molecular dynamics simulations. The results suggest Src tyrosine kinase can bind substrate positioning residues C‐terminal to the phosphoacceptor residue in an orientation similar to serine/threonine kinases, and unlike other tyrosine kinases. Mutagenesis corroborates this new perspective on tyrosine kinase substrate recognition. Rather than an evolutionary split between tyrosine and serine/threonine kinases, a change in substrate recognition may have occurred within the TK group of the human kinome. Protein tyrosine kinases have long been therapeutic targets, but many marketed drugs have deleterious off‐target effects. More accurate knowledge of substrate interactions of tyrosine kinases has the potential for improving drug selectivity.  相似文献   
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Archives of Microbiology - Cellulose is the most abundant natural polymer present on Earth in the form of agriculture waste. Hydrolysis of agriculture waste for simple fermentable reducing sugars...  相似文献   
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International Journal of Peptide Research and Therapeutics - Whipple’s disease is one of the rare maladies in terms of spread but very fatal one as it is linked with many disorders (like...  相似文献   
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DNA barcodes in species tagging have become a popular tool for taking inventories of species from different groups worldwide. The present study aimed to generate DNA barcodes of butterfly species from the Western Himalayas in Uttarakhand, India. The Indian Western Himalayan region (IWHR) has been explored to a limited extent about butterfly species’ diversity. However, the IWHR is prone to environmental change, and slight variations in climatic conditions can influence species diversity and change butterflies' range. The mitochondrial cytochrome c oxidase I (COI) gene was first used to generate the DNA barcode for butterflies from this region on a broad scale. 28 morphologically identified species, consisting of 102 sequences, were finally grouped into 26 species, with only two species showing ambiguity in species identification. These species had < 3% sequence variations from their neighboring relatives, suggesting cryptic species diversity. Generated sequences were also compared with the GenBank data of conspecific geographical locations, which showed intraspecies variation ranging from 1.3% to 7.3%. It was also noted that butterfly species have both intra and interspecies sequence divergence. In the phylogenetic-based species identification, a total of 28 species belonging to 4 families of butterflies were successfully discriminated, and two species at the genus level, which had high intra-specific divergence (0.025), were considered. However, the high intra-species sequence divergence observed may represent the presence of hidden species.  相似文献   
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