HIV neuropathogenesis and therapeutic strategies

Abstract Human immunodeficiency virus (HIV)-l neuropathogenesis can be divided into three important components: (i) virus entry into the nervous system; (ii) the role of viral proteins and/or cellular products in neural tissue damage; and (iii) the mechanisms of neuronal injury/death. Both blood derived macrophages or trafficking HIV-1 infected T-lymphocytes have been implicated in viral entry to the central nervous system (CNS). The major cell type harboring productive HIV-1 infection in the nervous system is the perivascular macrophage/ microglia. The HIV-1 infection of brain astrocytes, restricted to the expression of regulatory gene products, may cause astrocyte dysfunction and contribute to neuronal injury or to disruption of the blood-brain barrier (BBB). Studies of cerebrospinal fluid and postmortem tissues reveal chronic inflammation/immune activation in the nervous system during the later stages of HIV-1 infection associated with disruption of BBB integrity. Blood-brain barrier damage may underlie the white matter pallor described in HIV-1 infection and could result in further entry into the CNS of toxic viral or cellular products, or additional HIV-1 infected cells. The HIV infected and activated macrophages/microglia produce excessive amounts of pro-inflammatory cytokines, including tumor necrosis factor alpha, and platelet activating factor. These products are directly toxic to human neurons in vitro. The HIV-1 envelope glycoprotein, gp 120 may stimulate the release of toxic factors from brain macrophages. Blocking N-methyl-D-aspartate (NMDA; or AMPA) glutamate receptors can antagonize candidate toxins of both viral and cellular origin. It has been postulated that (weak) excitotoxicity leads to oxidative stress in neurons and ultimately to apoptosis. Neuronal apoptosis occurs in the brains of both children and adults with HIV-1 infection. This understanding of HIV neuropathogenesis implies that therapeutic strategies should include: (i) anti-retroviral medications to decrease systemic and CNS virus load, and possibly to prevent perinatal transmission of HIV; (ii) anti-inflammatory compounds to decrease the chronic immune activation in microglia and allow the restoration of BBB integrity; and (iii) neuroprotective compounds to reduce neuronal injury and apoptotic death.     

Detection of hepatocellular carcinoma after interferon therapy for chronic hepatitis C: Clinical study of 26 cases

The clinical findings in 26 patients in whom hepatocellular carcinoma (HCC) was detected after the start of interferon (IFN) therapy for chronic hepatitis C were analysed. Histological study before IFN therapy showed that 34.6% of patients were categorized as stage 3 (septal fibrosis with architectural distortion; the 0–4 scale) and 80.8% demonstrated at least some evidence of septal fibrosis or more advanced features. The AFP levels examined before IFN therapy were more than 20 ng/mL in 13 patients (84.6% of those studied). One of 26 patients had a complete response to IFN therapy, while six of 26 patients had only a partial response. HCC was detected within 1 year after the start of IFN therapy in 76.9% of patients. Thus, the possibility of the early occurrence of HCC or its existence at the time of therapy should be seriously considered when IFN therapy is contemplated. Patients with stage 3 or 3–4 histology may already have a small undetectable HCC before IFN therapy. Thus, for this reason, every patient treated with IFN should be examined at short regular intervals for the development of HCC during and after IFN therapy.     

110例嗜酸细胞增多性非变应性鼻炎的液氮冷冻治疗

１１０例嗜酸细胞增多性非变应性鼻炎的液氮冷冻治疗山西医学院第二附属医院（０３０００１）牛玉梅，刘学仁按Ｍｇｇｉｎｄ将常年性鼻炎分为三类：一类常年性变态反应性鼻炎；二类非变态反应性鼻炎伴鼻分泌物嗜酸细胞增多综合征也叫嗜酸细胞增多性非变态反应性鼻炎（Ｅｏｓｉｎｏｐｈｉｌｉｃｎｏｎａｌｌｅｒａｉｃｒｈｉｎｉｔｓ，ＥＮＲ）；三类自主神经性常年性鼻炎［１］。我们将ＥＮＲ中找不到致敏物，而与冷热空气有关与情绪无关的１１０例患者进行了液氮冷冻治疗。临床资料８０２例常年性鼻炎患者进行皮肤激发试验。４３７例找出了致敏物，进行特异性过敏诱因脱敏治疗或抗过敏药物治疗。３６５例试验阳性，其中有１３５例与冷热空气有关。ｌｌ０例行冷冻治疗。１ｌ０例中男５０例，女６０例；年龄最大６５岁，最小１６岁。１１０例均有间歇性的连续喷嚏发作，浆液性或粘液性鼻分泌物增多和鼻粘膜非充血性肿胀引起的堵塞，无因吸入致敏原诱发症状的病史；血清ＩｇＥ值不升高，特异性皮肤试验结果为阳性；鼻分泌物中嗜酸细胞阳性。方法：先将鼻腔内喷入１％地卡因溶液３次粘膜表面麻醉，用卷好的４厘米长、０．４～０．６厘米粗的棉棒沾上液氮在鼻镜直视下迅速插入鼻腔内。时间约１分钟左右（冷     

HCV HVR1准种在不同基因型丙型肝炎患者中的分布

目的:通过研究丙型肝炎病毒高变区1(HCV HVR1)准种复杂性与基因型之间的关系,探讨不同基因型HCV致病性差异的机制.方法:采用C区型特异性引物PCR法进行HCV基因分型,采用单链构象多态性聚合酶链反应法(SSCP法)检测HCV HVR1准种.结果:68例丙型肝炎患者中,Ⅱ型49例(72%),Ⅲ型13例(19%),Ⅱ、Ⅲ混合型6例(9%).Ⅱ型和Ⅱ、Ⅲ混合型HCV感染患者的HCV HVR1准种复杂性(SSCP条带数)明显高于Ⅲ型感染的患者,且与疾病严重程度关系密切.结论:HCV HVR1准种复杂性的差异可能是导致不同基因型HCV致病性差异的因素之一.     

丙型肝炎病毒E1E2蛋白原核表达载体的构建及表达产物的鉴定

目的 :构建丙型肝炎病毒 (HCV)包膜糖蛋白 (E1E2 )基因的原核表达载体 ,为研究HCVE1E2蛋白属性及基因免疫奠定基础。方法 :设计HCVE1E2区基因上、下游引物 ,分别引入BglⅡ及EcoRI酶切位点 ,以含有HCVH株基因序列的质粒pBRTM/HCV1- 30 11为模板 ,通过PCR扩增获得HCVE1E2区基因片段 ,将其克隆入原核表达载体pRSETA ,然后通过酶切和序列测定对其进行鉴定 ;将此表达载体转化入表达菌BL2 1(DE3)pLySs诱导表达 ,并采用SDS -PAGE对表达产物进行鉴定。结果 :经酶切及序列测定分析表明 ,成功地构建了重组原核表达载体pRSETA -HCVE1E2 ;SDS -PAGE显示目的蛋白大量表达 ,且呈非溶状态。结论 :HCVE1E2融合蛋白可以在大肠杆菌中大量表达 ,为HCVE1E2蛋白的制备及基因疫苗的研制奠定了基础。     

伤风净喷鼻液体外抗病毒作用的实验研究

目的　观察伤风净喷鼻液在体外的抗病毒作用。方法　先测定药物对细胞的毒性 ,观察细胞病变Cy topathceffect(CPE) ,找出最大无毒浓度 ;再测定流感病毒FM1株、合胞病毒Long株的病毒滴度。最后测定伤风净喷鼻液抑制各病毒对细胞产生细胞病变 (CPE)的作用。结果　实验表明伤风净喷鼻液抗流感病毒FM1株的最低有效浓度为1∶10 2 4,相当于伤风净喷鼻液原药浓度 1.0 5 5mg/ml ,抗合胞病毒Long株的最低有效浓度为 1∶40 96,相当于伤风净喷鼻液原药浓度 0 .2 64mg/ml。 结论　根据实验结果证明伤风净喷鼻液具有明显的抗流感病毒FM1株、合胞病毒Long株作用     

抗戊型肝炎病毒重组蛋白单克隆抗体的制备和初步应用

目的:制备抗-戊型肝炎病毒的单克隆抗体,并将其用于分析戊型肝炎病毒不同毒株结构蛋白的抗原表位。方法:采用来自墨西哥株(Mexicanstrain)的戊型肝炎病毒重组蛋白(p166Mex)免疫Balb/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞进行融合,经酶联免疫吸附试验(ELISA)法筛选阳性克隆,并将获得的单克隆抗体与戊型肝炎病毒缅甸株(Burmastrain)和美国株(USAstrain)的重组蛋白(p166Bur、p166US)进行交叉反应测定。结果:最终获得4株能稳定分泌抗-p166Mex的杂交瘤细胞株,即D8G10、E5E12、D4A3、B7E6。其中D8G10,E5E12和B7E6细胞株的培养上清液,还能分别与p166Bur和p166US重组蛋白发生阳性反应。结论:利用已获得的抗-p166Mex单克隆抗体,初步确定3种不同的戊型肝炎病毒重组蛋白(p166Bur、p166US、p166Mex)含有一种共同的抗原表位。     

湖南省乙肝病毒基因型分布及临床意义

目的 :研究湖南省乙肝病毒 (HBV)基因型分布及临床意义。方法 :选择湖南省HBVDNA阳性慢性乙肝病人共 185例 ,其中病毒携带者 (ASC) 4 2例 ,慢性轻、中度肝炎 (CH) 38例 ,重型肝炎 (FHF) 80例 (伴有肝硬化者 4 9例 ) ,肝细胞癌 (HCC) 2 5例 ,采用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法检测HBV基因型。结果 :基因型B136例 (73.5 % ) ,基因型C 4 9例 (2 6 .5 % )。基因型B在FHF中占绝对优势 (83.7% ) ,其次为HCC(76 % ) ,与ASC(5 7.1% )比较 ,差异有显著性 (P <0 .0 1)。与基因型B相比 ,基因型C在垂直传播感染者中多见 (38.8%与 13.2 % ,P <0 .0 0 1) ;HBeAg阳性率明显增高 (5 7.1%与 30 .9% ,P <0 .0 0 1) ;抗HBe阳性率明显下降 (36 .9%与 6 6 .2 % ,P <0 .0 0 1)。与基因型C相比 ,基因型B感染者ALT水平明显增高 (2 6 4 .5± 2 5 6 .5与 10 0± 12 0 .6 ,P <0 .0 0 1)。结论 :湖南省存在乙肝病毒基因型B和基因型C ;基因型B为优势基因型并与肝脏疾病活动性相关 ,基因型C与母婴垂直传播感染有关     

皮肤T细胞淋巴瘤患者的人类T淋巴细胞白血病病毒Ⅰ型感染

目的　研究皮肤T细胞淋巴瘤 (CTCL)患者中是否存在人类T淋巴细胞白血病病毒Ⅰ型 (HTLV Ⅰ )的感染。方法　检测CTCL患者血清中的HTLV Ⅰ抗体以及患者外周血细胞和活检标本中的前病毒DNA。结果　PCR法检测CTCL患者外周血样 5 7例 ,其中HTLV Ⅰ前病毒DNA阳性患者 6例 ;ELISA法检测CTCL患者 5 4例 ,其中 1例为可疑阳性 ;Western印迹法检测CTCL患者 18例 ,其中HTLV Ⅰ抗体阳性者 4例 ,此 4例患者前病毒DNAPCR结果也为阳性。结论　皮肤T细胞淋巴瘤患者存在HTLV Ⅰ病毒感染 ,CTCL与HTLV Ⅰ有一定的关系。HTLV Ⅰ病毒感染可能是CTCL发病的诱因之一。     

Naturally occuring antibodies against nerve growth factor in human and rabbit sera: comparison between control and herpes simplex virus-infected patients

Antibodies against nerve growth factor (NGF) in sera were detected by enzyme-linked immunosorbent assays (ELISA), by their isolation after passage of sera through NGF immunoadsorbent columns and by their specificity to bind and immunoprecipitate mouse NGF as well as to stain by immunohistochemical methods cellular sites of NGF synthesis. Increased levels of anti-NGF antibodies were found in sera of herpes simplex virus (HSV)-infected patients but not in HSV-inoculated rabbits. As HSV latency is known to be promoted by NGF in vitro, these results may suggest that anti-NGF antibodies modulate the cytokine function of NGF and thus might play a role in HSV infection. The biological function of circulating antibodies against NGF, in general, is now open to future investigation.