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African swine fever virus(ASFV), as a member of the large DNA viruses, may regulate autophagy and apoptosis by inhibiting programmed cell death. However, the function of ASFV proteins has not been fully elucidated, especially the role of autophagy in ASFV infection. One of three Pyrroline-5-carboxylate reductases(PYCR), is primarily involved in conversion of glutamate to proline. Previous studies have shown that depletion of PYCR2 was related to the induction of autophagy. In the present study, we found for the first time that ASFV E199 L protein induced a complete autophagy process in Vero and HEK-293 T cells. Through co-immunoprecipitation coupled with mass spectrometry(CoIP-MS)analysis, we firstly identified that E199 L interact with PYCR2 in vitro. Importantly, our work provides evidence that E199 L down-regulated the expression of PYCR2, resulting in autophagy activation. Overall, our results demonstrate that ASFV E199 L protein induces complete autophagy through interaction with PYCR2 and down-regulate the expression level of PYCR2, which provide a valuable reference for the role of autophagy during ASFV infection and contribute to the functional clues of PYCR2.  相似文献   
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《Biomarkers》2013,18(5):410-417
To explore the value of cystatin C for evaluating acute kidney injury (AKI) in haemorrhagic fever with renal syndrome (HFRS), the concentrations of cystatin C in serum and urine samples from HFRS patients were determined. The serum and urinary cystatin C concentrations significantly increased in HFRS patients compared with normal controls (p?<?0.001). In the acute phase of HFRS, urinary cystatin C increased to higher levels than serum creatinine, especially in severe or critical cases in the oliguric stage. Furthermore, higher levels of urinary cystatin C in the acute phase positively correlated with increased severity of the subsequent kidney injury. In conclusion, urinary cystatin C is a more sensitive clinical marker for AKI in HFRS, which may enable us to initiate treatment measures as early as possible.  相似文献   
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Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. From a preliminary screening of fungal phytotoxins, cyclopaldic acid ( 1 ), seiridin ( 2 ), sphaeropsidin A ( 4 ), and papyracillic acid ( 5 ) were evaluated for their biting deterrent and larvicidal activities against Ae. aegypti L. Because compounds 1, 2, 4 , and 5 exhibited mosquito biting deterrent activities and 1 and 4 demonstrated larvicidal activities, further structure? activity relationship studies were initiated on these toxins. In biting‐deterrence bioassays, 1, 2, 4 , and 5 , 3,8‐didansylhydrazone of cyclopaldic acid, 1F , 5‐azidopentanoate of cyclopaldic acid A, 1G , the reduced derivative of cyclopaldic acid, 1 H , isoseiridin ( 3 ), 2′‐O‐acetylseiridin ( 2A ), 2′‐oxoseiridin ( 2C ), 6‐O‐acetylsphaeropsidin A ( 4A ), 8,14‐methylensphaeropsidin A methyl ester ( 4B ), and sphaeropsidin B ( 4C ) showed activities higher than the solvent control. Sphaeropsidin B ( 4C ) was the most active compound followed by 2A , while the other compounds were less active. Biting‐deterrence activity of compound 4C was statistically similar to DEET. In the larvicidal screening bioassays, only compounds 1 and 4 demonstrated larvicidal activities. Based on LD50 values, compound 4 (LD50 36.8 ppm) was significantly more active than compound 1 (LD50 58.2 ppm). However, the activity of these compounds was significantly lower than permethrin.  相似文献   
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It is well known that evaluation of parameters for any mathematical model is always very important and often a very difficult problem. This is especially true for agents-based models because as a rule the evaluation of an agent's parameters can be made only based on available information from the higher levels of a complex system. Such problems can be ill-posed or even have a non-unique solution. That is why there is no general algorithm for solving these problems and a researcher has to search for it for every specific model type.  相似文献   
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Bartonella quintana is a bacterium that causes a broad spectrum of diseases in humans including trench fever. Humans were previously considered to be the primary, if not the only, reservoir hosts for B. quintana. To identify the animal reservoir and extend our understanding of the ecological and evolutionary history of B. quintana, we examined blood samples from macaques and performed multilocus sequence typing (MLST) analysis. We demonstrated the prevalence of B. quintana infection was common in macaques from main primate centres in mainland China. Overall, 18.0% (59/328) of rhesus macaques and 12.7% (39/308) of cynomolgus macaques were found to be infected with B. quintana by blood culture and/or polymerase chain reaction. The infection was more frequently identified in juvenile and young monkeys compared with adult animals. In contrast with the relatively low level of sequence divergence of B. quintana reported in humans, our investigation revealed much higher genetic diversity in nonhuman primates. We identified 44 new nucleotide variable sites and 14 novel sequence types (STs) among the B. quintana isolates by MLST analysis. Some STs were found only in cynomolgus macaques, while some others were detected only in rhesus macaques, suggesting evidence of host‐cospeciation, which were further confirmed by phylogenetic analysis and Splits decomposition analysis. Our findings suggest that trench fever may primarily be a zoonotic disease with macaques as the natural hosts.  相似文献   
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新型猪瘟疫苗研究进展   总被引:5,自引:0,他引:5  
猪瘟是由猪瘟病毒引起猪的一种急性、热性和高度接触性传染病.该病呈世界性分布,给世界养猪业造成了巨大的经济损失.目前,疫苗接种仍然是防控猪瘟的主要手段.虽然传统的猪瘟弱毒疫苗(如C株)安全有效,但猪瘟的临床表现发生了很大变化,呈现典型猪瘟和非典型猪瘟共存、隐性感染和持续感染并现,免疫失败的现象时有报道,且不能区分野毒感染和免疫接种.因此,研制安全、高效、能区分野毒感染和疫苗免疫动物(DIVA)的新型猪瘟疫苗极为必要.文中就近年来开发的核酸疫苗、病毒活载体疫苗、基于蛋白/肽的疫苗、基因缺失疫苗、嵌合瘟病毒疫苗等新型DIVA猪瘟疫苗作一综述.  相似文献   
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