2013-2018年太原市手足口病流行特征及病原学分析

目的 分析2013-2018年太原市手足口病(hand,foot and mouth disease,HFMD)流行及病原学特征,为HFMD的防控提供科学依据.方法 用Excel 2003及SaTScan9.4.1软件对太原市2013-2018年HFMD病例资料分别进行统计描述及时空聚集性分析,采用RT-PCR对部分H...     

肠道病毒71型吉林分离株的全基因组序列分析

目的对2011年吉林省肠道病毒71型(enterovirus type 71,EV71)分离株全基因组进行序列分析。方法将手足口病伴发重症脑炎患者的粪便样品接种至Vero细胞,分离EV71;采用RT-PCR法分8段扩增全基因组序列,进行双酶切及序列测定;应用Mega5软件构建EV71系统进化树;通过DNAMAN7和DNASTAR7软件进行EV71分离株核苷酸和氨基酸序列的同源性比较;经RDP4软件对EV71分离株进行同源重组分析。结果粪便样品接种至Vero细胞2 d后,细胞出现圆缩、透亮、聚堆的病变现象;各PCR扩增产物经双酶切鉴定,均可见与预期大小一致的目的条带;经种系进化树分析显示,EV71分离株属C4a亚型,命名为EV71-JiLin-11-China;其与A、B和C亚型间核苷酸序列的平均同源性分别为22.44%、17.72%和11.96%,与A、B和C亚型间氨基酸序列的平均同源性分别为96.0%、97.2%和97.3%;全基因同源重组分析显示,EV71分离株的165～1 946和7 289～7 366核苷酸区有重组现象,分别源于分离自湖北的C4a-EV71-Hubei-09-China及马来西亚的B4-SB2864-SAR-00和C1-S18062-SAR-98。结论 2011年吉林地区流行的EV71为C4a基因型,为EV71基因特征及流行病学的研究提供了实验依据。     

B族链球菌C5a肽酶表位的预测、分段表达及其免疫原性

目的应用生物信息学方法预测B族链球菌C5a肽酶蛋白(SCPB)的表位,分段表达其中4个功能活性区域,并分析其免疫原性。方法用预测程序ProPred和ANTIGENIC预测SCPB的表位;分别构建C5a肽酶4个目的片段的重组表达质粒,经酶切测序正确后,转化E. coli BL21(DE3),IPTG诱导表达,SDS-PAGE分析目的蛋白的表达形式及表达量;并经镍柱亲和层析纯化,纯化的重组蛋白进行蛋白质谱分析和Western blot分析后,皮下免疫小鼠,ELISA检测小鼠血清抗体水平。结果经预测,SCPB含1个既可结合MHC又具有B细胞表位特征的肽段。构建的4个重组表达质粒经酶切及测序鉴定正确,目的蛋白主要以可溶性形式表达,表达量约占菌体总蛋白的30%～70%。纯化的重组蛋白纯度可达90%,质谱分析表明与SCPB的相似性很高;Western blot分析表明,可与兔抗全长SCPB多克隆抗体反应。重组F1、FE、Fn蛋白免疫小鼠血清抗体滴度较高,三者差异无统计学意义;F2a蛋白抗体滴度最低,与F1、FE和Fn蛋白差异有统计学意义。结论已成功构建并高效表达了SCPB的4个功能活性区域;Fn是重要的免疫优势表位功能区;本文为B族链球菌毒力机制的研究及亚单位蛋白疫苗的研制奠定了基础。     

Metal-Sulfate Induced Generation of ROS in Human Brain Cells: Detection Using an Isomeric Mixture of 5- and 6-Carboxy-2',7'-Dichlorofluorescein Diacetate (Carboxy-DCFDA) as a Cell Permeant Tracer

Evolution of reactive oxygen species (ROS), generated during the patho-physiological stress of nervous tissue, has been implicated in the etiology of several progressive human neurological disorders including Alzheimer's disease (AD) and amylotrophic lateral sclerosis (ALS). In this brief communication we used mixed isomers of 5-(and-6)-carboxy-2',7'-dichlorofluorescein diacetate (carboxy-DCFDA; C(25)H(14)C(l2)O(9); MW 529.3), a novel fluorescent indicator, to assess ROS generation within human neuronal-glial (HNG) cells in primary co-culture. We introduced pathological stress using the sulfates of 12 environmentally-, industrially- and agriculturally-relevant divalent and trivalent metals including Al, Cd, Cu, Fe, Hg, Ga, Mg, Mn, Ni, Pb, Sn and Zn. In this experimental test system, of all the metal sulfates analyzed, aluminum sulfate showed by far the greatest ability to induce intracellular ROS. These studies indicate the utility of using isomeric mixtures of carboxy-H(2)DCFDA diacetates as novel and highly sensitive, long-lasting, cell-permeant, fluorescein-based tracers for quantifying ROS generation in intact, metabolizing human brain cells, and in analyzing the potential epigenetic contribution of different metal sulfates to ROS-generation and ROS-mediated neurological dysfunction.     

Difluoromethylornithine (DFMO), an Inhibitor of Polyamine Biosynthesis,and Antioxidant N-Acetylcysteine Potentiate Immune Response in Mice to the Recombinant Hepatitis C Virus NS5B Protein

Hepatitis C virus (HCV) is one of the main triggers of chronic liver disease. Despite tremendous progress in the HCV field, there is still no vaccine against this virus. Potential vaccines can be based on its recombinant proteins. To increase the humoral and, especially, cellular immune response to them, more effective adjuvants are needed. Here, we evaluated a panel of compounds as potential adjuvants using the HCV NS5B protein as an immunogen. These compounds included inhibitors of polyamine biosynthesis and urea cycle, the mTOR pathway, antioxidants, and cellular receptors. A pronounced stimulation of cell proliferation and interferon-γ (IFN-γ) secretion in response to concanavalin A was shown for antioxidant N-acetylcysteine (NAC), polyamine biosynthesis inhibitor 2-difluoromethylornithine (DFMO), and TLR9 agonist CpG ODN 1826 (CpG). Their usage during the immunization of mice with the recombinant NS5B protein significantly increased antibody titers, enhanced lymphocyte proliferation and IFN-γ production. NAC and CpG decreased relative Treg numbers; CpG increased the number of myeloid-derived suppressor cells (MDSCs), whereas neither NAC nor DFMO affected MDSC counts. NAC and DFMO suppressed NO and interleukin 10 (IL-10) production by splenocytes, while DFMO increased the levels of IL-12. This is the first evidence of immunomodulatory activity of NAC and DFMO during prophylactic immunization against infectious diseases.     

High Monocyte Count Associated with Human Cytomegalovirus Replication In Vivo and Glucocorticoid Therapy May Be a Hallmark of Disease

Cytomegalovirus (CMV) syndrome and infectious disease are defined as pathogen detection with appropriate clinical symptoms, but there are not pathognomonic signs of CMV disease. Although the prodrome of acute minor viral infections leukopenia (lymphopenia and neutropenia) is noted with onset of fever, followed by monocytosis, the role of monocytosis in CMV disease has not been described. Furthermore, under influence of corticosteroid therapy, CMV reactivation and monocytosis are described, but without a strict relationship with steroids dose. In the study, the monocyte level was investigated during the CMV infectious process. Regrettably, a non-selected group of 160 patients with high CMV viremia showed high dispersion of monocyte level and comparable with the median value for healthy subjects. Therefore, we investigated monocyte level in CMV-infected patients in relation to the logarithmic phase of the infectious process. Samples from patients with active CMV replication (exponential growth of CMV viremia) were tested. Significant monocytosis (above 1200/µL) during the logarithmic phase of CMV infection (with exponent between 3.23 and 5.77) was observed. Increased count and percentage of monocytes correlated with viral replication in several clinical situations except when there was a rapid recovery without relapse. Furthermore, glucocorticoids equivalent to 10 and 20 mg of dexamethasone during a 2–3-week period caused monocytosis—significant increase (to 1604 and 2214/µL, respectively). Conclusion: In light of the logarithmic increase of viral load, high monocytosis is a hallmark of CMV replication. In the COVID-19 era, presence of high virus level, especially part of virome (CMV) in the molecular technique, is not sufficient for the definition of either proven or probable CMV replication at any site. These preliminary observations merit additional studies to establish whether this clinical response is mediated by monocyte production or by decrease of differentiation to macrophages.