重组人免疫缺陷病毒Ⅰ型逆转录酶的纯化及其动力学性质

目的纯化重组人免疫缺陷病毒Ⅰ型逆转录酶（ＨＩＶ－１ＲＴ），筛选新的ＨＩＶ－１ＲＴ抑制剂。方法在适宜的培养条件下诱导工程菌Ｅ．ｃｏｌｉＪＭ１０９（ＰＫＲＴ２）可高效表达重组人免疫缺陷病毒Ⅰ型（ＨＩＶ－１）逆转录酶（ＲＴ）。应用ＤＥＡＥ－纤维素和磷酸纤维素离子交换柱层析法从细菌裂解液中分离、纯化重组ＲＴ。结果１升细菌培养液可得到１．１ｍｇ产物。ＳＤＳ－聚丙烯酰胺凝胶电泳分析显示所纯化的重组ＲＴ为由两个分子量分别为６６ｋＤ和５１ｋＤ的亚基组成的杂二聚体。酶活性测定结果表明，经纯化的重组ＲＴ具有很高的逆转录酶活性（比活力为１．４×１０４ｕｍｇ）。结论本文通过对ＲＴ反应条件的研究，优化了ＲＴ反应系统，并测定了磷甲酸钠（ＰＦＡ）对重组ＲＴ的抑制效应，结果表明ＰＦＡ对重组ＲＴ的抑制反应动力学机制与天然ＲＴ相同，从而进一步说明用此法纯化的重组ＲＴ可直接用于抗ＨＩＶ药物的筛选与评价。     

Biological properties of HIV-1 variants circulating among drug users in Russia

Human immunodeficiency virus type 1 variants belonging to subtype A, as well as recombinant gaga/engvB variants, derived from HIV-infected patients living in the Moscow and Perm Regions, were isolated and characterized. Intravenous administration of psychoactive drugs was a major risk factor of the infection for all the patients. All the examined isolates of HIV-1 types A and A/B were shown to be characterized by a low virus-specific activity and to be used as secondary CCR5 and CXCR4 protein receptors. The findings suggest that the domination of subtype A variant in this risk group is unassociated with fundamental differences in biological properties between the isolates of this subtype and recombinant viruses.     

Morphologic features of pneumonia in young children of the Northeast USSR]

Post-mortem investigations of the lungs of 160 children below 2 years of age who had died of acute pneumonia in Magadan were carried out with the use of histological, histochemical, histotopographic, macro- and micromorphometric methods. As to duration of the disease, pneumonias were divided arbitrarily into acute (up to 21 days) and protracted one (from 3 weeks to 2 months). It was established that acute pneumonia in children in Magadan were of polysegmentary character, with involvement in the process of 3-7 segments of each lung and with exclusion from the act of breathing up to 80-90% of the lung's surface. Most often the pathological process was localized in the posterior and postero-inferior segments. Along with pneumonia, which was of interstitial, focal or mixed character, atelectasis and acute emphysema developed. Histologically described acute pneumonias were characterized by pronounced lesions of the tracheobronchial tree, drastic circulatory disorders with formation of "garland-like" structures from the expanded capillary network of the lungs, the presence of hyaline membranes and large hyperchromic conglomerates. In protracted pneumonias in addition lesions of the argyrophilic and elastic carcass of the lungs were observed.     

Malignant histiocytosis: a study on clinicopathological features and cell origin]

Thirty-one autopsy cases previously diagnosed as malignant histiocytosis (MH) were studied by means of immunohistochemical staining. Antibodies detecting the formalin resistant epitopes on T-cells, B-cells and those of histiocyte/monocyte origin were used. It was shown that the malignant histiocytes reacted only to the cell markers derived from histiocyte/monocyte, and only a part of lymphocytes showed positive reaction to the T and B cell markers. It is suggested that the histiocyte/monocyte lineage is the possible origin of the malignant proliferating cells in MH. The clinicopathological features and the differentiation of MH from familial erythrophagocytic lymphohistiocytosis, virus-associated hemophagocytic syndrome and malignant lymphoma are described. The pathogenesis, the causes of death and the points for attention in the treatment of MH are also discussed.     

Epidemiological features of a new strain of the influenza A virus--influenza A (H1N2) circulating in England and its public health implications

The UK influenza season of 2001/2002 was characterized by widespread geographic circulation of a new subtype of influenza A (H1N2) virus throughout the duration of the season. Younger children were predominantly infected, suggesting primary infection. Despite this, the public health impact of this new virus was minimal. It remains to be seen whether influenza A (H1N2) virus will persist and co-circulate with the previously circulating subtypes of influenza A (H1N1 and H3N2), or whether it was a sporadic recombination event that will disappear. Ultimately, the emergence of a new strain highlights the importance of continual surveillance of circulating viruses.     

HIV-1 Nef基因在THP-1细胞的表达和活性检测

目的将HIV-1 Nef基因转染THP-1细胞,获得稳定表达Nef蛋白的细胞克隆,为研究Nef对巨噬细胞生物学活性的影响奠定实验基础。方法将质粒pcDNA3.1(+)-Nef和pcDNA3.1(+()阴性对照)转染THP-1细胞,通过逆转录-聚合酶链反应(RT-PCR)、Western blot、细胞免疫荧光等方法检测目的蛋白在真核细胞内的表达及定位,采用共转染法将荧光报告基因转染THP-1Nef和THP-13.1细胞,通过测定荧光(RLU)值来评价Nef蛋白的生物学活性。结果转染细胞经G418筛选后获得稳定表达Nef的THP-1细胞株,RT-PCR及Western blot结果表明Nef在真核细胞中成功表达,细胞免疫荧光结果显示,THP-1-Nef细胞表达的Nef蛋白主要定位于细胞质中。荧光酶标仪检测转染了HIV-1LTR-Luc和NFκB-Luc荧光报告基因的THP-1-Nef和THP-1-3.1细胞的RLU值。结论成功建立了THP-1-Nef细胞稳定表达细胞株,检测了其生物学活性,为进一步研究其作用机制实验奠定基础。     

The reproduction of the hepatitis A virus in cell cultures]

A comparative analysis of reproduction of 9 strains of hepatitis A viruses (HSA-15, CF-979, MI, MBB 11/5, H-141, KMW-1, GBM, IH-26, WR-61) from different regions of the world in cell cultures (PLC/PRF/5, HEL-240, FRhK-4, MK) revealed the differences in the capacity of the viruses for reproduction in these cell lines. The factors influencing HAV reproduction in cell cultures such as temperature, medium, and sera were studied. In one-cycle infection, accumulation of vRNA and formation of virus particles were analysed.     

Structural variability ofenv andgag gene products from a highly cytopathic strain of HIV-1

Summary The glycoprotein precursor of the highly cytopathic Zairian virus HIV1-NDK synthesized in CEM leukemic cells displayed a molecular mass of 140 kDa (gp 140) as compared to the 160 kDa of gp 160 of HIV1-LAV prototype strain. This precursor was cleaved to produce a smaller than prototype extracellular envelope glycoprotein (gp 100) and a transmembrane component with a usual size (gp 41). Immunoprecipitates from tunicamycin-treated infected cells demonstrated the presence of a non-glycosylated precursor of 100 kDa for HIV1-LAV prototype strain and 90 kDa for HIV1-NDK. Digestion of labeled precipitates with a mixture of endoglycosidase F and glycopeptidase F reduced the size of HIV1-LAV gp 160 and gp 120 to 100 and 60 kDa, respectively, while HIV1-NDK gp 140 and gp 100, after treatment with the same enzymes, displayed an apparent molecular mass of 90 kDa and 55 kDa, respectively. From these data we conclude that HIV1-LAV gp 120 and HIV1-NDK gp 100 differ both in their proteic moiety (60 kDa and 55 kDa, respectively) and in their carbohydrate moiety (60 kDa and 45 kDa, respectively). These differences could not be deduced from the available gene sequences of the two viruses. A chimeric virus containing the first 124 amino acid residues of the envelope glycoprotein coded by HIV1-LAV sequence and the rest by HIV1-NDK displayed normal size envelope glycoproteins, demonstrating the involvement of this N-terminal sequence in the alteration of the molecular mass characteristic of HIV1-NDK gp 140 and gp 100. Finally, characterization of thegag gene products from both strains demonstrated that HIV1-NDK p 18 and p 15 have a slower electrophoretic mobility as compared to its HIV1-LAV counterparts. Therefore, structural properties of HIV1-NDKenv andgag products, reflected by their unusual electrophoretic mobilities, may be responsible for HIV1-NDK biological properties.     

中国株HIV-1 gp120核酸疫苗的实验免疫研究

目的　探讨表达中国株HIV 1gp12 0基因的核酸疫苗在小鼠体内的免疫反应。方法　将表达HIV 1gp12 0的核酸疫苗质粒pVAXP经肌肉注射免疫Balb c小鼠 ,检测免疫小鼠脾CD4 +、CD8+T细胞亚群的数量 ,脾特异性CTL杀伤活性和血清抗体滴度。结果　重组质粒pVAXP免疫组小鼠脾CD4 +、CD8+T细胞亚群的数值均比对照组高 (P <0 .0 5 ) ;免疫组脾特异性CTL杀伤活性与对照组相比差异极显著 (P <0 .0 1) ;血清抗体滴度显著高于对照组 (P <0 .0 5 )。结论　表达HIV 1gp12 0基因的核酸疫苗质粒pVAXP能诱导小鼠产生特异性细胞和体液免疫。     

Rotavirus infection in a maternity home based on virological and serological study data]

The studies carried out in a maternity house, employing a set of virological and serological methods, revealed the facts of introduction of rotavirus infection into the maternity house, and followed the further spread of the infection. Epidemiological surveys evaluated the sources of infection (parturients, newborns, medical personnel), means of spread of rotavirus infection, and analysed the epidemiological advantages of wards for mother and newborn baby staying together.     

Iatrogenic diseases in children based on the data from pathologicoanatomic autopsies]

Iatrogenic diseases were studied on the material of 500 autopsies taken without selection of children who died in 1988-1989. Iatrogenic diseases were found in 185 cases (37%), most frequently at the age of 7-28 days (65.8% of all dead children), least frequently at the age up to 7 days (18.5%). Total number of iatrogenic diseases (270) exceeded the number of observations. Nosological structure is given: complications of reanimation and intensive therapy were most frequent (71.5% of all iatrogenesis), surgical iatrogenesis was 19.2%. Iatrogenic diseases were the only cause of death or an important factor in the death in 13.6% of all autopsies of children born alive.     

尿路致病性大肠杆菌ppk1基因缺失株的构建及其生物学特性研究

目的构建尿路致病性大肠杆菌CFT073的聚磷酸盐激酶1（ polyphosphate kinase , PPK1）基因敲除株,并初步探索其体外生物学特性。方法以CFT073株为研究对象,利用Red同源重组技术敲除CFT073的ppk1基因,构建敲除株△pk1;通过细胞实验即以人膀胱癌上皮细胞5637为体外模型对CFT073野生型菌株、敲除菌株的黏附及侵袭能力进行比较;采用96孔板结晶紫染色法分析CFT073 ppk1基因敲除对其生物膜形成能力的影响。结果成功构建了CFT073 ppk1基因敲除株;敲除ppk1后,细菌对膀胱癌上皮细胞的黏附、侵袭能力较野生株都明显减弱;△pk1在各时间点570 nm处结晶紫吸光度值均较野生株的低。结论利用Red同源重组技术可成功敲除CFT073的ppk1基因,ppk1在尿路致病性大肠杆菌黏附、侵袭尿路上皮及生物膜形成过程中可能发挥了重要作用。     

HIV-1蛋白诱导T细胞产生IFN-γ反应特征及对HIV-1感染者病情进展的影响

目的 探讨HIV-1特异性T细胞反应特征及对HIV-1感染者病情进展的影响.方法 通过合成重叠肽技术及ELISPOT技术,采用队列研究方法对37名HIV-1感染者的病毒特异性T细胞免疫反应进行分析.结果 83.78%(31/37)的HIV-1感染者对1个或多个合成肽反应(反应强度大于50 SFU/106 PBMCs).HIV-1B型病毒不同蛋白均可激发HIV-1感染者的特异性T细胞反应,其中HIV-1 Gag蛋白被识别的频率最高,81%的HIV-1感染者识别HIV-1 Gag而且HIV-1 Gag蛋白诱导的T细胞反应强度最高,相对强度达到28.25%,明显高于其他蛋白,差异具有统计学意义(F=17.969,P<0.001);重叠肽诱导T细胞分泌IFN-γ反应频率、反应强度在HIV-1感染无症状期和艾滋病期无明显区别,但是HIV-1 Gag蛋白诱导的T细胞反应强度在无症状期明显高于艾滋病期.结论 HIV-1B型病毒不同基因编码蛋白激发T细胞分泌IFN-γ反应小同,其中HIV-1 Gag蛋白特异性T细胞在控制病情进展方面发挥了重要作用.     

HIV-1 Subtype distribution in morocco based on national sentinel surveillance data 2004-2005

Background

Use of dietary supplements is common among people living with HIV/AIDS. Because dietary supplements are used in the context of other health behaviors, they may have direct and indirect health benefits. However, supplements may also be associated with vulnerability to medical misinformation and unfounded health claims. We examined use of dietary supplements among people living with HIV/AIDS (PLWH) and the association between use of dietary supplements and believing medical misinformation.

Methods

A convenience sample of 268 men and 76 women living with HIV was recruited from AIDS services and clinics in Atlanta, GA. Participants completed measures of demographic and health characteristics, dietary supplement use, beliefs about dietary supplements, internet use, and an internet evaluation task designed to assess vulnerability to medical misinformation.

Results

One out of four PLWH currently used at least one dietary supplement product excluding vitamins. Dietary supplement use was associated with higher education and greater use of the internet for health-related information. Dietary supplement users also endorsed greater believability and trust in unfounded claims for HIV cures.

Conclusions

Dietary supplement use is common among PLWH and is associated with a broad array of health information seeking behaviors. Interventions are needed to reduce the vulnerability of PLWH, particularly dietary supplement users, to medical misinformation propagated on the internet.     

The expression of a fragment of the HIV-1 Nef gene in Escherichia coli bacteria]

The presence of antibodies to p27, the product of gene Nef, may be an important diagnostic sign since some sera from subjects of the risk groups negative to HIV-1 structural proteins may contain antibody to p27. The study resulted in construction of a hybrid plasmid determining in E coli bacteria the synthesis of a hybrid protein the N-terminus part of which is represented by full-size beta-galactosidase and the C-terminus by a part of protein p27 with the main immunoreactive epitopes. The resulting polypeptide specifically interacts with sera of the infected subjects and may be used for detection of antibodies to the protein Nef in the blood of virus-carriers.     

Comparative study of antigens specific for hepatitis B in transfected cell cultures]

A comparative study of antigens detected in the livers of patients with hepatitis B. in the mesonephros of the human tissue--chick embryo system infected with the agents isolated from the blood of hepatitis patients, as well as antigens detectable in cell cultures transfected by the DNA isolated from these tissues was carried out. The results are in favour of the hypothesis on the integrational nature of serum hepatitis.