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Coronavirus (CoV) infections are commonly associated with respiratory and enteric disease in humans and animals. In 2012, a new human disease called Middle East respiratory syndrome (MERS) emerged in the Middle East. MERS was caused by a virus that was originally called human coronavirus-Erasmus Medical Center/2012 but was later renamed as Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV causes high fever, cough, acute respiratory tract infection, and multiorgan dysfunction that may eventually lead to the death of the infected individuals. The exact origin of MERS-CoV remains unknown, but the transmission pattern and evidence from virological studies suggest that dromedary camels are the major reservoir host, from which human infections may sporadically occur through the zoonotic transmission. Human to human transmission also occurs in healthcare facilities and communities. Recent studies on Middle Eastern respiratory continue to highlight the need for further understanding the virus-host interactions that govern disease severity and infection outcome. In this review, we have highlighted the major mechanisms of immune evasion strategies of MERS-CoV. We have demonstrated that M, 4a, 4b proteins and Plppro of MERS-CoV inhibit the type I interferon (IFN) and nuclear factor-κB signaling pathways and therefore facilitate innate immune evasion. In addition, nonstructural protein 4a (NSP4a), NSP4b, and NSP15 inhibit double-stranded RNA sensors. Therefore, the mentioned proteins limit early induction of IFN and cause rapid apoptosis of macrophages. MERS-CoV strongly inhibits the activation of T cells with downregulation of antigen presentation. In addition, uncontrolled secretion of interferon ɣ-induced protein 10 and monocyte chemoattractant protein-1 can suppress proliferation of human myeloid progenitor cells.  相似文献   
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D. J. Morré  M. Paulik 《Protoplasma》1993,177(1-2):15-22
Summary This study was to determine if feline immunodeficiency virus (FIV)-infected and uninfected Crandall feline kidney (CRFK) cells exhibited a low temperature (16°C) block in membrane trafficking between transitional endoplasmic reticulum and Golgi apparatus represented by intermediate compartment formation. Cells were cultured at different temperatures and membrane changes involving the Golgi apparatus and Golgi apparatus-associated membrane structures were monitored by electron microscopy and quantitated. With 30 min of incubation, membranes of the Golgi apparatus stack increased in amount at temperatures of 16°C and below compared to temperatures above 18°C. The increase was greatest along the major polarity axis as evidenced by an increased stack height. Neither the number of cisternae per stack nor the average stack diameter (width) was affected by temperature. The response was maximal between 15 and 30 min of low temperature treatment of the cells. Results with cells infected and uninfected with feline immunodeficiency virus were similar. The increase in stack height was due primarily to an increase of membranes at the cis face (cis Golgi apparatus network). At 18°C, membranes of the trans Golgi apparatus network accumulated suggesting that import from the cis Golgi network could proceed at this temperature, whereas exit from the trans Golgi network was still at least partially blocked. Also increased at 16°C and below were numbers of transition vesicles in the space between the Golgi apparatus and the transitional endoplasmic reticulum associated with the cis Golgi apparatus face. The results suggested interruption of the orderly flux of membranes into the Golgi apparatus at 16°C and below. Moreover, the block appeared to be reversible. Upon transfer from 16°C to 37°C, there was a time-dependent decrease in the accumulations of cis compartment membrane accompanied by a corresponding equivalent increase in the membranes of the trans Golgi apparatus compartment.  相似文献   
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Two RNA-containing viruses, feline infectious peritonitis virus (FIPV) and feline immunodeficiency virus (FIV), have been observed to infect cheetahs. Although both viruses cause lethal immunogenetic pathology in domestic cats, only FIPV has documented pathogenesis in cheetahs. We summarize and update here a worldwide survey of serum and plasma from cheetah and other nondomestic felids for antibodies to FIV and FIPV, based on Western blot and immunofluorescence assays. FIPV exposure shows an acute pattern with recognizable outbreaks in several zoological facilities, but is virtually nonexistent in sampled free-ranging populations of cheetahs. FIV is more endemic in certain natural cheetah populations, but infrequent in zoological collections. FIV exposure was also seen in lions, bobcats, leopards, snow leopards, and jaguars. FIV causes T-cell lymphocyte depletion and associated diseases in domestic cats, but there is little direct evidence for FIV pathology in exotic cats to date. Because of the parallels with a high incidence of simian immunodeficiency virus in free-ranging African primates without disease, the cat model may also reflect historic infections that have approached an evolutionary balance between the pathogen and immune defenses of their feline host species. Published 1993 Wiley-Liss, Inc.  相似文献   
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当前因SARS-CoV-2感染而引起的2019新型冠状病毒肺炎(COVID-19)肆虐全球,严重危害人类健康。SARS-CoV-2感染性强,危重症患者死亡率高,尽管各种各样的治疗正在进行临床试验,但目前尚无有效的治疗方法。间充质干细胞(mesenchymal stem cell,MSC)在临床前试验中对多种疾病有良好的治疗效果,因而受到了广泛地关注。MSC可能利用分化潜能诱导分化成功能性肺样细胞、免疫调节与免疫细胞互作、抑制炎症来降低促炎细胞因子分泌、迁移和归巢靶向损伤肺部、抗病毒作用来减少肺上皮细胞中的病毒复制、产生细胞外囊泡来修复受损的组织,进而使COVID-19患者肺功能逐渐恢复正常,缓解并达到治疗COVID-19的目的。综合讨论了COVID-19的基本特征和当前主要治疗手段,同时总结了MSC在COVID-19中的临床研究和当前面临的挑战,探讨了MSC治疗COVID-19的应用前景,为MSC在COVID-19中的治疗提供了理论基础和现实依据。  相似文献   
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探讨严重急性呼吸综合征冠状病毒2型(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)免疫球蛋白M(Immunoglobulin M,IgM)/免疫球蛋白G(Immunoglobulin G,IgG)、病毒核酸和白细胞介素6(interleukin 6, IL-6)的联合检测在2019冠状病毒病(coronavirus disease 2019, COVID-19)诊断和治疗中的临床价值。本研究按照《新型冠状病毒肺炎诊疗方案(试行第七版)》的标准收集了93例确诊病例(51例危重型、18例重型,15例轻型和9例普通型)和20例疑似病例(核酸检测阴性但临床症状和CT检测结果均符合标准)。选取110例儿科、妇科、肿瘤、血液和消化等疾病患者并排除COVID-19作为对照组。采用全自动化学发光免疫分析技术和电化学发光技术检测所有研究对象血清中SARS-CoV-2 IgM/IgG和IL-6。用实时荧光定量反转录聚合酶链反应对病例组和对照组的咽拭子进行SARS-CoV-2核酸检测。结果发现,血清IgM、IgG和IL-6在疑似病例中的阳性率分别为85%、75%和0%,在确诊病例中的阳性率分别为98.9%、95.7%和75.2%(其中危重型分别为100%、100%和100%,重型分别为94.4%、100%和97.9%,轻型分别为100%、93.3%和5%、普通型分别为100%、66.7%和0%)。IL-6和 SARS-CoV-2 IgM/IgG表达水平的改变与患者疾病的严重程度存在一定的关联性,差异有统计学意义(χ2=273.51,χ2=149.37;P<0.05)。血清IL-6和SARS-CoV-2 IgM/IgG的联合检测可作为诊断和治疗COVID-19的监测指标,也可作为SARS-CoV-2核酸检测假阴性的有效互补。  相似文献   
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Tian  Suyan  Zhu  Xuetong  Sun  Xuejuan  Wang  Jinmei  Zhou  Qi  Wang  Chi  Chen  Li  Li  Shanji  Xu  Jiancheng 《中国病毒学》2020,35(6):811-819
Virologica Sinica - The temporal change patterns of laboratory data may provide insightful clues into the whole course of COVID-19. This study aimed to evaluate longitudinal change patterns of key...  相似文献   
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Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an infectious disease with multiple severe symptoms, such as fever over 37.5°C, cough, dyspnea, and pneumonia. In our research, microRNAs (miRNAs) binding to the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory-related coronavirus (MERS-CoV), and SARS-CoV-2 were identified by bioinformatic tools. Five miRNAs (hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-16-5p, and hsa-miR-196a-1-3p) were found to commonly bind to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also identified miRNAs that bind to receptor proteins, such as ACE2, ADAM17, and TMPRSS2, which are important for understanding the infection mechanism of SARS-CoV-2. The expression patterns of those miRNAs were examined in hamster lung samples infected by SARS-CoV-2. Five miRNAs (hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-221-3p, hsa-miR-140-3p, and hsa-miR-422a) showed differential expression patterns in lung tissues before and after infection. Especially, hsa-miR-15b-5p and hsa-miR-195-5p showed a large difference in expression, indicating that they may potentially be diagnostic biomarkers for SARS-CoV-2 infection.  相似文献   
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The pandemic outbreaks of coronavirus disease 2019 (COVID‐19), caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), spread all over the world in a short period of time. Efficient identification of the infection by SARS‐CoV‐2 has been one of the most important tasks to facilitate all the following counter measurements in dealing with the infectious disease. In Taiwan, a COVID‐19 Open Science Platform adheres to the spirit of open science: sharing sources, data, and methods to promote progress in academic research while corroborating findings from various disciplines has established in mid‐February 2020, for collaborative research in support of the development of detection methods, therapeutics, and a vaccine for COVID‐19. Research priorities include infection control, epidemiology, clinical characterization and management, detection methods (including viral RNA detection, viral antigen detection, and serum antibody detection), therapeutics (neutralizing antibody and small molecule drugs), vaccines, and SARS‐CoV‐2 pathogenesis. In addition, research on social ethics and the law are included to take full account of the impact of the COVID‐19 virus.  相似文献   
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