Injecting drug use and blood-borne viruses: a comparison of rural and urban Victoria, 1990-95

Most studies of injecting drug users (IDUs) have included only urban IDUs; information about rural IDUs is scarce. Recognizing this, the Victorian Injecting Drug Users Cohort Study (VICS) recruited IDUs from rural Victoria as well as Melbourne (population 3.2 million in 1995), capital city of the state of Victoria, Australia. Examination of data collected from IDUs living in M elbourne and the Western District (largest city: Warrnambool, pop. 27 734) revealed numerous differences in behaviour and serology. The primary drug for most Western District IDUs was amphetamines while Melbourne IDUs preferred heroin. Injecting and sharing frequencies were much lower in the rural sample. Hepatitis C antibody prevalence at first test was significantly higher in M elbourne IDUs, although this was clearly related to the difference in primary drugs; conversely, incidence among Western District amphetamine injectors was 16.2 per 100 person-years (py) (during 18.5 py), yet no conversions occurred in metropolitan amphetamine injectors in 29.8 py. Western District IDUs were less educated and more likely to be unemployed and of aboriginal descent than metropolitan IDUs. Variation between populations of Victorian IDUs has implications for the delivery of IDU-related health services; of particular concern is the possibility that hepatitis C has been spreading relatively rapidly among rural IDUs. \[Aitken C, Brough R, Crofts N. Injecting drug use and blood-borne viruses: a comparison of rural and urban Victoria, 1990-95. Drug alcohol Rev 1999;18:47-52]     

Molecular strategies for the treatment of malignant glioma—genes, viruses, and vaccines

The standard treatment paradigm of surgery, radiation, and chemotherapy for malignant gliomas has only a modest effect on survival. It is well emphasized in the literature that despite aggressive multimodal therapy, most patients survive approximately 1 year after diagnosis, and less than 10% survive beyond 2 years. This dismal prognosis provides the impetus for ongoing investigations in search of improved therapeutics. Standard multimodal therapy has largely reached a plateau in terms of effectiveness, and there is now a growing body of literature on novel molecular approaches for the treatment of malignant gliomas. Gene therapy, oncolytic virotherapy, and immunotherapy are the major investigational approaches that have demonstrated promise in preclinical and early clinical studies. These new molecular technologies each have distinct advantages and limitations, and none has yet demonstrated a significant survival benefit in a phase II or III clinical trial. Molecular approaches may not lead to the discovery of a “magic bullet” for these aggressive tumors, but they may ultimately prove synergistic with more conventional approaches and lead to a broadening of the multimodal approach that is the current standard of care. This review will discuss the scientific background, therapeutic potential, and clinical limitations of these novel strategies with a focus on those that have made it to clinical trials.     

Attempted isolation of viruses from myasthenia gravis thymus

A systematic study of thymus homogenates and cell suspensions from 13 patients with myasthenia gravis (MG) of recent onset, and 6 non-myasthenic controls, has failed to detect or isolate virus by cell culture with 'rescue techniques', electron microscopy, or intracerebral inoculation into neonatal mice. These results do not support the case for persistent viral infection in the thymus, and impose constraints on hypotheses of a viral aetiology of MG.     

Genetic Evidence for a Tacaribe Serocomplex Virus, Mexico

We isolated arenavirus RNA from white-toothed woodrats (Neotoma leucodon) captured in a region of Mexico in which woodrats are food for humans. Analyses of nucleotide and amino acid sequence data indicated that the woodrats were infected with a novel Tacaribe serocomplex virus, proposed name Real de Catorce virus.     

The epidemiology of febrile illness in sub-Saharan Africa: implications for diagnosis and management

BackgroundFever is among the most common symptoms of people living in Africa, and clinicians are challenged by the similar clinical features of a wide spectrum of potential aetiologies.AimTo summarize recent studies of fever aetiology in sub-Saharan Africa focusing on causes other than malaria.SourcesA narrative literature review by searching the MEDLINE database, and recent conference abstracts.ContentStudies of multiple potential causes of fever are scarce, and for many participants the infecting organism remains unidentified, or multiple co-infecting microorganisms are identified, and establishing causation is challenging. Among ambulatory patients, self-limiting arboviral infections and viral upper respiratory infections are common, occurring in up to 60% of children attending health centres. Among hospitalized patients there is a high prevalence of potentially fatal infections requiring specific treatment. Bacterial bloodstream infection and bacterial zoonoses are major causes of fever. In recent years, the prevalence of antimicrobial resistance among bacterial isolates has increased, notably with spread of extended spectrum β-lactamase-producing Enterobacteriaceae and fluoroquinolone-resistant Salmonella enterica. Among those with human immunodeficiency virus (HIV) infection, Mycobacterium tuberculosis bacteraemia has been confirmed in up to 34.8% of patients with sepsis, and fungal infections such as cryptococcosis and histoplasmosis remain important.ImplicationsUnderstanding the local epidemiology of fever aetiology, and the use of diagnostics including malaria and HIV rapid-diagnostic tests, guides healthcare workers in the management of patients with fever. Current challenges for clinicians include assessing which ambulatory patients require antibacterial drugs, and identifying hospitalized patients infected with organisms that are not susceptible to empiric antibacterial regimens.     

双调控溶瘤腺病毒介导超抗原SEA基因靶向膀胱肿瘤表达

目的 构建携带SEA基因的选择性增殖腺病毒,体外实验观察SEA基因的表达及其刺激淋巴细胞对肿瘤的杀伤功能.方法 构建一种由端粒酶(hTERT)和缺氧反应元件(HIF)双重启动的携带SEA的选择性增殖腺病毒,通过逆转录-聚合酶链反应(RT-PCR)检测SEA在肿瘤细胞内mRNA表达,免疫荧光定位SEA表达于肿瘤细胞,Western blot测定蛋白表达,显微镜下动态观测淋巴细胞与肿瘤细胞共培养.酶联免疫吸附试验(ELISA)检测白细胞介素(IL)-4分泌.结果 琼脂糖电泳252 bp处可见清晰条带;免疫荧光及Western blot用考马斯亮蓝染色显示在27 kDa附近可见蛋白清晰表达;淋巴细胞与肿瘤细胞共培养12、24、48 h实验组肿瘤细胞明显少于对照组,ELISA检测IL-4分泌量实验组均高于对照组(t=2.585 P＜0.05).结论 携带SEA基因的选择性腺病毒成功构建并表达目的基因,证明对肿瘤细胞的杀伤作用.     

重症手足口病患者气管插管吸出液中肠道病毒71型的分离与鉴定

目的分离鉴定重症手足口病患者气管插管吸出液标本的EV71病毒株。方法将采集的标本过滤除菌接种于MA104细胞,出现细胞病变效应(CPE)后提取培养上清液中的RNA,用国家标准检测引物进行RT-PCR鉴定;用特异性引物进行PCR获得VP1全序列,测序后以MEGA4软件与各血清型代表株VP1序列进行分析并构建分子进化树。结果接种标本3 d后细胞出现CPE,经RT-PCR鉴定为EV71,对其VP1全序列进行测定分析后,确定其为C4亚型,并绘制了分子进化树。结论手足口病患者下呼吸道分泌物EV71的分离鉴定,为手足口病肺损伤发病机制的研究提供了依据。     

表达端粒酶逆转录酶siRNA的溶瘤腺病毒对裸鼠肾癌移植瘤的治疗作用

目的 观察表达针对端粒酶逆转录酶(hTERT)基因的小干扰RNA(hTERT siRNA)的溶瘤腺病毒(ZD55-hTERT)抑制肾癌移植瘤生长作用.方法 荷肾癌裸鼠随机分4组,每组8只.瘤体内分别注射ZD55-hTERT、增殖缺陷型腺病毒(Ad-hTERT)、溶瘤腺病毒ZD55-EGFP及磷酸盐缓冲液(PBS),每次注射病毒7×108pfu/只,连续注射3 d.注射后第7天,每组处死3只取肿瘤组织,免疫组织化学检测肿瘤hTERT、E1A表达及凋亡.第50天时处死动物测量肿瘤体积.结果 ZD55-hTERT、Ad-hTERT、ZD55-EGFP及PBS处理组肿瘤体积(mm3)分别为:124.1±27.5、609.0±102.5、499.8±77.1、1552.1±206.4,ZD55-hTERT处理组与各组之间差异有统计学意义(P<0.01).Ad-hTERT处理组肿瘤无E1A表达,ZD55-hTERT处理组E1A大量表达,表明病毒复制.ZD55-hTERT处理组肿瘤hTERT表达显著低于Ad-hTERT处理组,凋亡细胞阳性率均显著高于Ad-hTERT处理组.结论 表达hTERT siRNA的溶瘤腺病毒ZD55-hTERT具有更强的抑制肾癌生长作用.