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41.
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梁文焰  马爱霞 《中国全科医学》2020,23(29):3661-3666
丙型肝炎病毒(HCV)感染在慢性肾功能不全患者中较常见,尤其是在进行透析的患者中,HCV感染较普通患者的风险极大增加,同时还会导致肝细胞癌及肝硬化的发病率明显升高。近年来直接抗病毒药物(DAAs)在慢性丙型肝炎的治疗中取得了较好的疗效及安全性,本文通过总结DAAs在丙型肝炎合并透析患者中的应用进展,发现对于基因1~6型HCV合并透析患者,推荐使用G/P方案;由于索磷布韦(SOF)经肾脏代谢,在重度肾损害人群中的血药浓度较高,因此SOF组合方案并不推荐用于丙型肝炎合并透析患者的治疗。  相似文献   
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Hepatitis C is a global public health problem, and Pakistan is the second largest country in the globe with highest prevalence rate of hepatitis C virus (HCV). Until 2014, pegylated interferon (PEG-IFN) plus ribavirin (RBV) has been the standard therapy for HCV, however, owing to its adverse side effects and very low sustained virologic response (SVR) rates therapeutics trend is shifted toward direct-acting antivirals. Tripartite motif containing 22 (TRIM22) is a dynamic antiviral protein that can inhibit multiple viruses in vivo. Expression of TRIM22 mRNA has been linked to outcome of PEG-IFN and ribavirin therapy, where its higher expression leads to rapid virus clearance. However, in terms of therapy with direct-acting antiviral (DAA) or double DAA, impact of TRIM22 expression is largely unknown. These new drugs show more than 90% of SVR rates and lesser side effects and have proven to be better than IFN therapy. Endogenous IFN system suppresses various pathogens through the induction of antiviral effectors termed as interferon-stimulating genes (ISGs). We have studied the expression levels of one of these antiviral effectors, TRIM22 in response to sofosbuvir (SOF) and daclatasvir (DAC) in combination with RBV, using quantitative PCR in the peripheral blood mononuclear cells (PBMCs) of HCV-infected patients. We have observed sustained virus clearance in more than 90% of patients treated with DAA and double DAA and have seen the expression of TRIM22 to be higher in patients who attained SVR as compared to the untreated patients. We have also observed downregulation of TRIM22 in patients who failed to attain rapid virus clearance, and upregulation in those who achieved rapid clearance of virus. Genetic factors that determine the lower TRIM22 expression in these patients are needed to be explored that may also play a role in lower response to anti-HCV therapy. Endogenous IFN system and effects of antiviral proteins in response to DAA therapy is needed to be studied in order to better understand the host response toward these drugs to make them more effective.  相似文献   
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目的 探讨分离于广西猪流感病毒SW/Guangxi/NS2783/2010和SW/Guangxi/NS650/2012跨种属感染人肺腺癌A549细胞的miRNA93和miRNA192对病毒复制及宿主抗病毒免疫的影响。方法 通过测定不同稀释浓度的病毒感染细胞HA滴度值,确定病毒最佳稀释浓度。荧光定量PCR检测病毒感染细胞后miRNA93和miRNA192表达,Western blot检测病毒NP和HA蛋白表达水平;转染miRNA93和miRNA192抑制剂后,重新检测miRNA93、miRNA192、IFN-β及病毒NP、HA蛋白表达水平。结果 不同稀释度病毒感染人A549细胞后HA滴度的结果显示病毒SW2783的最佳稀释度为10-3,而SW650的HA滴度无明显变化趋势,提示病毒SW2783对人A549细胞具有较好的适应性和感染能力。荧光定量PCR和Western blot结果提示两株病毒感染细胞后病毒NP和HA蛋白表达均先升高后降低,加入miRNA93抑制剂,两株病毒NP和HA蛋白的表达均上调;加入miRNA192抑制剂,病毒SW2783的HA蛋白表达下调(P=2.10×10-4),而SW650的HA蛋白表达上调(P=5.45×10-5),NP蛋白反而下调(P=0.034);ELISA结果提示病毒SW2783和SW650感染细胞后炎症因子IFN-β表达水平随感染时间延长而升高。结论 研究表明miRNA93和miRNA192的表达与SIV病毒增殖及宿主抗病毒免疫有关,可作为干预猪流感病毒跨种属感染的新靶点。  相似文献   
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Although infectious mononucleosis due to Epstein-Barr virus (EBV) is a common disease among young individuals, central nervous system (CNS) complications are rare. In this report, we describe a case of CNS complications caused by EBV in a previously healthy young woman. She presented to our hospital with a 9-day history of headache and sore throat, followed by the development of fever and facial edema 6 days prior to admission. On Day 2 of admission, she was confused (Glasgow Coma Scale score: 10 points) and had fever, muscle weakness in her right arm and leg, stiff neck, and roving eye movement. We detected EBV in a cerebrospinal fluid (CSF) sample using a polymerase chain reaction (PCR) test. The magnetic resonance imaging of her brain revealed dural enhancement and right parietal and temporal lobe lesions. She was treated with acyclovir and high-dose steroid therapy. She responded well to treatment, recovered without neurologic sequelae, and was discharged home on Day 12.Our experience suggests that PCR detection of EBV DNA in CSF may be useful in diagnosing EBV encephalitis and that prognosis may be associated with an area of the brain that is affected and the time from symptom onset to starting treatment.  相似文献   
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《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
49.
目的探讨极速实时荧光聚合酶链反应(polymerase chain reaction,PCR)、实时荧光PCR、酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)和胶体金免疫层析法(gold immunochromatography assay,GICA)4种方法检测新型布尼亚病毒的特异度和灵敏度,为发热伴血小板减少综合征的早期诊断提供依据。方法采集2017年6月1日至9月30日山东大学附属济南市传染病医院86例临床诊断为发热伴血小板减少综合征患者的血清样本,分别应用极速实时荧光PCR、实时荧光PCR、ELISA和GICA 4种方法进行检测。统计学分析采用χ^2检验。结果86份患者血清标本中,极速实时荧光PCR、实时荧光PCR、IgM-ELISA、IgG-ELISA、IgM-GICA、IgG-GICA的新型布尼亚病毒阳性分别为82份(95.34%)、79份(91.86%)、41份(47.67%)、8份(9.3%)、19份(22.09%)和3份(3.49%)。极速实时荧光PCR特异度为100%,灵敏度达到1×103拷贝/mL,3次重复扩增试验显示其Ct值变异系数均<2%。在发热伴血小板减少综合征进展的1期、2期、3期病程中,极速实时荧光PCR的阳性检出率为41份(97.62%)、34份(94.44%)、7份(87.50%),实时荧光PCR的阳性检出率为39份(92.86%)、33份(91.67%)、7份(87.50%),在1期和2期两个病程,极速实时荧光PCR阳性检出率略高;IgM-ELISA阳性检出率从1期(28.57%)到3期(87.50%)显著增高,2期、3期与1期相比,差异均有统计学意义(χ^2=8.347、7.561,均P<0.01);IgM-GICA的阳性检出率从1期(14.29%)到2期(33.33%)也有增高,差异有统计学意义(χ^2=3.962,P<0.05),但与其他方法相比,其检出率偏低。1期,实时荧光PCR阳性检出率显著高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=33.740、55.080、49.010、64.340,均P<0.01)。2期,实时荧光PCR的阳性检出率高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=7.700、46.720、23.700、50.630,均P<0.01)。3期,极速实时荧光PCR、实时荧光PCR和IgM-ELISA表现出同样高的阳性检出率,远高于IgG-ELISA和GICA(IgM和IgG)。实时荧光PCR阳性检出率和IgG-ELISA、IgM-GICA、IgG-GICA之间差异均有统计学意义(均χ^2=6.250,P<0.05)。结论极速实时荧光PCR在新型布尼亚病毒的早期检测中有更高的灵敏度和特异度,且重复性好、稳定度高,与传统实时荧光PCR相比大大缩短了扩增时间,对发热伴血小板减少综合征的早期快速诊断具有重要价值。  相似文献   
50.
目的 研究乙型肝炎病毒(HBV)自身增强子I(enhancerI,ENHI)对HBV DNA疫苗免疫应答的影响。方法 采用PCR法以HBVadr亚型全基因DNA序列为模板分别扩增表面抗原(HBsAg)和HBsA-ENHI基因片段,重组到载体VR1012中,构建两种HBV DNA疫苗,转染CADS-7细胞及HepG2细胞并免疫BALB/c小鼠。采用蛋白印迹、ELISA、ELISPOT等方法检测其在COS-7和HepG2细胞内的表达及小鼠的体液及细胞免疫应答效果。结果 转染的HepG2和COS-7细胞均表达HBsAg;连接ENHI的HBV DNA疫苗转染HepG2细胞后HBsAg表达量明显升高,两种疫苗转染COS-7细胞表达HBsAg无明显差异;免疫小鼠后第2周产生HBsAb及HBsAg特异性细胞毒T淋巴细胞(CTL),两种疫苗免疫产生的HBsAb及HBsAg特异性CTL无明显差异。结论ENHI可使HBV DNA疫苗转染HepG2细胞表达HBsAg明显增加,对转染COS-7细胞表达HBsAg及接种BALB/C小鼠引起的免疫应答无明显影响。  相似文献   
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