HIV-1感染对T和B细胞核内UNG2 mRNA表达的影响

目的:探讨HIV-1感染是否影响细胞中UNG2的表达.方法:采用四步法SYBR green Ⅰ实时定量RT-PCR,对HIV-1感染者的T和B淋巴细胞,以及HIV-1感染的C8166细胞核内UNG2 mRNA的表达进行测定.结果:UNG2 mRNA的表达在HIV-1感染者的T细胞和HIV-1感染的C8166细胞中被明显上调,分别是对照的8.76倍和8.14倍,而在HIV-1感染者的B细胞中却没有被上调.结论:HIV-1感染导致的UNG2表达上调,可能通过减少TCR的多样性削弱Th的功能,另一方面可能有利于病毒对UNG2的包装.

与植物多糖硫酸酯结合的HIV-1ⅢB灭活病毒免疫小鼠的研究

目的：为了探讨植物多糖硫酸酯（’&&(）与)*+%$ 结合后，能否诱导,-./+#0 的)*+%$ 暴露出中和抗体的表 位，用它作为灭活疫苗以便诱导产生中和抗体。方法：用’&&( 结合的灭活,-./+#0 作为免疫原，与佐剂混和后，免疫 0(102 3 小鼠，制备出免疫血浆。用41-5( 检测血浆内抗,-./+ 特异性-)6 抗体的滴度，用改良的活细胞染色法中和试验检测 免疫血浆的抗,-./+#0 的中和活性。结果：从与’&&( 结合的,-./+#0 免疫组的动物获得的免疫血浆内抗,-./+ 抗体的滴 度（7 组：+8 # 9 +$" ；: 组：+8 # 9 +$" ）比未结合’&&( 的,-./+#0 免疫组（;8 < 9 +$# ）高，雌性小鼠的免疫血浆的特异性抗体滴 度比雄性的高& 倍。所有免疫组获得的免疫血浆均没有抗,-./+ 中和活性。结论：’&&( 与)*+%$ 相互作用不能诱导暴露出 )*+%$ 的中和抗体表位，但’&&( 可以增强机体免疫原的抗体反应强度，提示它可以作为免疫增强剂用于疫苗研究。

Subdivision-stabilised immersed b-spline finite elements for moving boundary flows

An immersed finite element method is presented to compute flows with complex moving boundaries on a fixed Cartesian grid. The viscous, incompressible fluid flow equations are discretized with b-spline basis functions. The two-scale relation for b-splines is used to implement an elegant and efficient technique to satisfy the LBB condition. On non-grid-aligned fluid domains and at moving boundaries, the boundary conditions are enforced with a consistent penalty method as originally proposed by Nitsche. In addition, a special extrapolation technique is employed to prevent the loss of numerical stability in presence of arbitrarily small cut-cells. The versatility and accuracy of the proposed approach is demonstrated by means of convergence studies and comparisons with previous experimental and computational investigations.

银额果蝇的B染色体研究 1: 昆明群体的Bs数目和频率

银额果蝇昆明群体有丝分裂中期核型中存在B染色体, 出现频率为69.1%在已 研究过的来自各个地区的银额果蝇中, 昆明群体的B染色体频率最高。B染色体 数目为1—6条。该群体内单雌系间的B染色体数目不同, 个体间和细胞间的B染色 体数目也不同。在核型中, B染色体最小, 形态稳定, 点状, C-带和G-带呈阳性 。 图版1图2表1参12

银额果蝇的B染色体研究2: 昆明群体的生活力和B染色体的关系

银额果蝇的B染色体在其生长和发育过程中具双重性调节作用。一方面, B染色体以单一的形式存在于单雌系核型中, 即1B或2Bs可刺激生长发育,增强生活力。另一方面, 在单雌系的细胞中存在多条B染色体, 并形成核型多态性, 似乎对生长发育有一定的抑制作用而减弱其生活力。图1表1参5

Stability and molecular modeling of triplex DNA inhibiting DNA binding protein binding to the core promoter of hepatitis B virus.

Two three-dimensional structure models of the 21nt oligodeoxyribonucleotides, CPI (G3TG-2TGT2G5TG2TGT) and CP3 (TGTG2TGST2GTG2TG3), were constructed by InsightII (MSI) software in IRIS Indigo2 (SGI) workstation using the crystal structure of TAT tripler formation as the template. The initial structures subsequently were minimized by molecular mechanics. The final structures were believed as the dominant conformation. The results showed that the energy of CP1 is lower than that of CP3, and the former is more stable than the latter. Moreover, the results further proved that the 21nt oligodeoxyribo-nucleotide CP1 stably combines with the core promoter (Cp) fragment of hepatitis B virus (HBV) to form a tripler DNA, and CP1 specifically inhibits a specific cellular factor (DNA binding protein) binding to Cp fragment. These results indicated that specific repression of gene transcription of HBV DNA might be possible by tripler-formation DNA.

On-going generation of multiple forms of HIV-1 intersubtype recombinants in the Yunnan Province of China

Objectives: To investigate the molecular epidemiology of HIV in China's Yunnan Province, where the initial HIV-1 outbreak among injecting drug users (IDU) occurred in 1989, and to analyse the genesis and interrelationship of the epidemic with that in surrounding areas. Design: A molecular epidemiological investigation was conducted among IDU in three prefectures in Yunnan Province, including Wenshan (east), Honghe (southeast) and Dehong (west). Methods: Thirty-nine specimens were collected from consenting IDU in 2000-2001. The nucleotide sequences of 2.6 kb gag-RT and 340 base pair (bp) env (C2/V3) regions were determined. Phylogenetic tree and recombination breakpoint analyses were performed. Results: The circulating recombinant form (CRF), CRF08_BC, predominated in east Yunnan near Guangxi Province (89% in Wenshan and 81% in Honghe), whereas it was not detected in Dehong(0/14) in the west. In contrast, 71% (10/14) of the Dehong isolates were unique recombinant forms (URF), mostly between subtypes B' (Thailand variant of subtype B) and C, with distinct profiles of recombination breakpoints. The subtype B' accounts for the remaining 29% (4/14) of Dehong isolates. Interestingly, two Honghe isolates (2/16) shared some of the precise B'/C recombination breakpoints with CRF07_BC. Conclusion: New recombinant strains are arising continually in west Yunnan near the Myanmar border. Some appeared to be secondary recombinants derived from CRF07_BC that had further recombined with other strains. The uneven distribution of subtypes, CRF and URF, suggests the presence of independent transmission networks and clusters among IDU in Yunnan. (C) 2002 Lippincott Williams Wilkins.