Quantitative HIV-1 proviral DNA detection: a multicentre analysis

Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients.     

中国蜘蛛抱蛋属一新记录种——合瓣蜘蛛抱蛋

首次报道中国蜘蛛抱蛋属一新记录种——合瓣蜘蛛抱蛋Aspidistra connata H.-J.Tillich,该种与辐花蜘蛛抱蛋A.subrotata Y.Wanet C.C.Huang相似,但叶片长椭圆形至长卵状椭圆形,花被顶端8～10裂,裂片线形,顶端联合不分开,形成一个笼状包围着雌蕊可与后者区别。凭证标本存放于广西植物标本馆(IBK)。     

矮晚柚的组织培养与快速繁殖

以矮晚柚种子萌发的无菌苗为实验材料,利用茎尖和上胚轴诱导丛生芽的发生,利用丛生芽获得再生植株。实验表明:矮晚柚成熟和未成熟种子在1/2MS、MS上均能萌发,萌发率最高可达96%,成熟种子萌发的无菌苗更利于后期的分化。最适外植体为无菌苗的上胚轴,筛选出丛生芽最佳增殖培养方案为MS+6-BA 2.0 mg·L~(-1)+NAA 0.1 mg·L~(-1)+蔗糖40 g·L~(-1)+靠近茎尖上胚轴,最高增殖系数达8.4,最佳生根培养基为1/2MS+NAA 0.2 mg·L~(-1)+IBA 0.2 mg·L~(-1)+活性炭0.2 g·L~(-1),生根率达90%以上。移栽至蛭石+珍珠岩+营养土(1:1:2)的营养砵上,成活率可达80%。     

Laboratory and Clinical Predictors of Disease Progression following Initiation of Combination Therapy in HIV-Infected Adults in Thailand

BACKGROUND: Data on determinants of long-term disease progression in HIV-infected patients on antiretroviral therapy (ART) are limited in low and middle-income settings. METHODS: Effects of current CD4 count, viral load and haemoglobin and diagnosis of AIDS-defining events (ADEs) after start of combination ART (cART) on death and new ADEs were assessed using Poisson regression, in patient aged ≥18 years within a multi-centre cohort in Thailand. RESULTS: Among 1,572 patients, median follow-up from cART initiation was 4.4 (IQR 3.6-6.3) years. The analysis of death was based on 60 events during 6,573 person-years; 30/50 (60%) deaths with underlying cause ascertained were attributable to infections. Analysis of new ADE included 192 events during 5,865 person-years; TB and Pneumocystis jiroveci pneumonia were the most commonly presented first new ADE (35% and 20% of cases, respectively). In multivariable analyses, low current CD4 count after starting cART was the strongest predictor of death and of new ADE. Even at CD4 above 200 cells/mm(3), survival improved steadily with CD4, with mortality rare at ≥500 cells/mm(3) (rate 1.1 per 1,000 person-years). Haemoglobin had a strong independent effect, while viral load was weakly predictive with poorer prognosis only observed at ≥100,000 copies/ml. Mortality risk increased following diagnosis of ADEs during cART. The decline in mortality rate with duration on cART (from 21.3 per 1,000 person-years within first 6 months to 4.7 per 1,000 person-years at ≥36 months) was accounted for by current CD4 count. CONCLUSIONS: Patients with low CD4 count or haemoglobin require more intensive diagnostic and treatment of underlying causes. Maintaining CD4≥500 cells/mm(3) minimizes mortality. However, patient monitoring could potentially be relaxed at high CD4 count if resources are limited. Optimal ART monitoring strategies in low-income settings remain a research priority. Better understanding of the aetiology of anaemia in patients on ART could guide prevention and treatment.     

车轮虫分类与系统发育研究进展

车轮虫属一大类寄生性纤毛虫原生动物，可不同程度地给宿主造成危害，故对其研究既具有理论意义，又具有经济价值。文中简单回顾了车轮虫的分类研究和系统发育研究的历史。在分类学研究领域方面，全面介绍了目前车轮虫科已发现属的寄生部位和地理分布等；而系统发育研究领域方面，则介绍了车轮虫研究在萌芽期、探索期和发展期这三个时期的进展，包括形态学和分子生物学两方面的研究内容。并对该领域今后应进行的研究提出了建议。     

Genetic analysis of fluvastatin response and dyslipidemia in renal transplant recipients

The Assessment of Lescol in Renal Transplantation clinical trial demonstrated the efficacy of fluvastatin in reducing cardiovascular (CV) disease in renal transplant recipients. The study included a voluntary pharmacogenetic component, enrolling 1,404 patients, which allowed association testing of baseline measures and longitudinal analysis of the 707 fluvastatin-treated and 697 placebo-treated individuals. A candidate gene approach, examining 42 polymorphisms in 18 genes, was used to test for association between selected polymorphisms and major adverse cardiac events, graft failure, change in LDL and HDL cholesterol, and baseline LDL and HDL cholesterol. Reported associations between cholesteryl ester transfer protein (CETP) and baseline HDL cholesterol were replicated, with four previously implicated single nucleotide polymorphisms significantly associated in males and one in females; tests of reported associations between CETP and CV disease yielded varying results. We found no evidence for genetic factors affecting fluvastatin response. Polymorphisms in 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) previously reported to affect the efficacy of pravastatin did not show a similar effect on the reduction of LDL cholesterol by fluvastatin.     

Complete Genomic Sequence Analysis of a New SV40 Isolate

The genome of a new SV40 strain (SV-IMB) isolated from a rhesus monkey was completely sequenced and compared with other isolates. The results showed that the whole genome contains 5246bp, and the average identity of SV-IMB was 98.1% as compared to other SV40 isolates. Its regulatory region is composed of a complete enhancer and a defective enhancer. Amino acid changes occurred to some extent in both the large T antigen (T-Ag) and VP1 region. The findings demonstrate that the SV-IMB is a new SV40 isolate.     

冻融作用对陆地生态系统氮循环关键过程的影响效应及其机制

冻融作用是中、高纬度及高海拔地区土壤普遍存在的一种自然现象,是非生长季陆地生态系统氮循环的重要影响因素.冻融作用主要通过改变土壤的理化性质及生物学性状来影响氮素在土壤中的迁移与转化.目前,冻融作用对陆地生态系统氮循环各个过程影响的研究结果不尽一致,理论机制尚不明晰,研究方法也需进一步地探索与创新,因此有必要对现有成果进行梳理和分析,以更好地把握冻融作用下的氮循环过程.本文结合国内外已有研究成果,论述了冻融作用对陆地生态系统氮循环关键过程（氮矿化、固持、硝化与反硝化过程、氮淋溶及气态损失）的影响效应及其主要机制,对目前研究中存在的不足进行了剖析,并对未来研究中迫切需要关注的重点研究方向进行了探讨与展望.     

薇甘菊可溶性蛋白和抗氧化酶活性对田野菟丝子不同寄生密度的响应

为探求利用寄生植物田野菟丝予对入侵杂草薇甘菊进行生物控制的有效措施,研究了薇甘菊对0、1、2、4和8棵田野菟丝子幼苗寄生在可溶性蛋白和一些抗氧化酶活性方面的响应.寄生后30 d,1棵田野菟丝子/株薇甘菊（以下简称棵/株）以上的寄生密度导致薇甘菊可溶性蛋白含量显著降低.和对照相比,在寄生密度为1棵/株时,超氧物歧化酶(S...