腺病毒伴随病毒表达载体表达人乳头瘤病毒18型E6E7基因构建及其转化作用的鉴定

目的：探讨人乳头瘤病毒（HPV）的E6E7基因在细胞恶性转化中所起的作用。方法：将人乳头瘤病毒（HPV）的E6E7基因克隆至腺病毒伴随病毒表达载体中，通过包装的重组病毒感染，将E6E7基因导入并整合到永生293细胞的基因组中。结果：本研究成功地构建了HPV18 E6E7 AAV病毒并感染了永生293细胞，PCR／Southern杂交分析表明E6E7基因在转化细胞293TL中确有表达，转化细胞293TC和293TL具有明显的转化表型，和亲本293细胞相比，生长速度快，接触抑制消失，集落形成率提高20倍，且集落明显增大，形成时间短。结论：成功地构建了HPV18 E6E7 AAV病毒，HPV18 E6E7基因引起永生化人上皮细胞293的恶性转化。此病毒可用于感染正常上皮细胞，研究其致癌机制。     

人癌胚抗原重组痘苗病毒转染树突状细胞体外诱导的抗肿瘤免疫

目的：研究人癌胚抗原重组痘苗病毒（rV-CEA)转染外周血树突状细胞（DC）后在外体诱导的抗CEA分泌性肿瘤免疫。方法：分离晚期结肠癌患者的外周血单核细胞，在体外用人重组粒－巨噬细胞集落刺激因子（GM－CSF）及白细胞介素4（IL－4）培养成DC，再用rV-CEA转染DC后激发自体T细胞，观察其体外激发自体T细胞的增殖能力及其诱导的细胞毒性T淋巴细胞（CTL）对自体CEA分泌性肿瘤细胞的杀伤活性，并与野生型痘苗病毒（W－VV）及无病毒转染的DC所激发的T细胞进行比较。结果：经rV-CEA转染的DC能显著刺激自体T细胞的增殖，其激活的T细胞对CEA分泌性自体肿瘤细胞具有特异性杀伤作用。结论：rV-CEA转染的DC可以诱导体CEA分泌性肿瘤免疫。     

Assessment of thymic output in common variable immunodeficiency patients by evaluation of T cell receptor excision circles

Common variable immunodeficiency (CVID) is a heterogeneous syndrome characterized by repeated infections and hypogammaglobulinaemia. Additionally, T-cell abnormalities including lymphopenia, decreased proliferation to mitogens and antigens, and the reduced production and expression of cytokines, have also been observed. In this study we have investigated the expression of naive, memory and activation markers in T-cell subpopulations in 17 CVID patients in comparison to age-matched normal controls. The numbers of CD4+ T cells, including CD45RA+CD62L+ and, to a lesser extent, CD45RA-CD62L+/RA+CD62L- were significantly reduced in patients, whereas CD8+ T cells were within normal range. In contrast, HLA-DR+ cells were increased both in CD4+ and CD8+ T cells. To assess the thymic output, we analysed the presence of T-cell receptor excision circles (TRECs) in CD4+ and CD8+ T cells by quantitative PCR. TRECs were decreased significantly in patients and the rate of TREC loss was higher with increasing age. TRECs correlated with naive CD4+ T cells, whereas there was an inverse relationship between TRECs and CD8+HLA-DR+ and CD8+CD45RA-CD62L+/RA+CD62L- T cells. Our results suggest the presence of a defect in the naive T cell compartment with origin at the thymic level in CVID, and indicate that TREC may be a useful marker to monitor thymic function in this primary immunodeficiency.     

Soluble IL-2 receptor and tumour necrosis factor-alpha in plasma of haemophilia patients infected with HIV.

We measured plasma concentrations of soluble receptors for IL-2 (sIL-2R) and tumour necrosis factor-alpha (TNF-alpha) in 149 haemophilia patients. Soluble IL-2R levels were elevated in 37% of 62 HIV-seronegative patients (mean 570 +/- 27 U/ml versus 361 +/- 17 U/ml in the control group, P less than 0.0001), in 78% of 68 HIV-seropositive patients (928 +/- 49 U/ml, P less than 0.0001), and in 95% of 19 AIDS/ARC patients (1578 +/- 199 U/ml, P less than 0.0001 compared with controls and with HIV-seronegative patients; P less than 0.005 compared with HIV-seropositive asymptomatic patients). A negative correlation was observed between sIL-2R, relative and absolute numbers of CD4+ cells (P less than 0.0001), and CD4/CD8 ratios (P less than 0.0001). There was also a negative correlation between sIL-2R in plasma and the cellular expression of IL-2R (P less than 0.001). We found a significant association of sIL-2R and plasma neopterin (P less than 0.0001). With progression of the disease from HIV-seronegative to seropositive without symptoms and to full manifestation of AIDS/ARC, sIL-2R plasma levels increased. The highest levels were found at the time of diagnosis of AIDS/ARC, but the levels decreased again during the following 18 months. Eight per cent of HIV-seronegative patients, 32% of HIV-seropositive patients, and 24% of patients with AIDS/ARC had increased plasma TNF-alpha. We conclude that sIL-2R and TNF-alpha plasma levels are elevated in HIV-infected haemophilia patients and that sIL-2R is a marker for disease progression from asymptomatic HIV-seropositive to AIDS/ARC.     

Galanin receptors in the post-mortem human brain. Regional distribution of I-galanin binding sites using the method of in vitro receptor autoradiography

The distribution of putative receptors for the peptide galanin was studied in the normal post-mortem human brain by using ¹²⁵I-galanin (0.5 nM) in combination with in vitro receptor autoradiography. Specific binding of ¹²⁵I-galanin was found in a large number of brain areas throughout the neuraxis. Highest binding densities occurred in the basal forebrain and hypothalamus, while the basal ganglia, major parts of the thalamus and the tectum were found to be poor in binding sites. All cortical areas harboured ¹²⁵I-galanin binding, and in the visual cortex a laminated pattern was present. In the hippocampus, ¹²⁵I-galanin binding occurred in layer 2 of the entorhinal cortex, in the uncus and in the hippocampal-amygdala area. In the brain-stem, ¹²⁵I-galanin binding was found in serotoninergic and noradrenergic cellgroups as well as in the reticular formation and in the parabrachial nuclei. Galanin receptors may, thus, mediate the response of galanin in numerous structures in the human brain.     

The gap effect and inhibition of return: interactive effects on eye movement latencies

Three experiments are reported with two types of manipulations that are known to affect the latency with which subjects can initiate saccadic eye movements. The first manipulation involves the temporal relation between the offset of a visual fixation point and the onset of a peripheral target (the gap effect). The second manipulation involves the prior allocation and removal of visual attention (inhibition of return). In two experiments, the gap effect was smaller for saccades to previously attended locations than to previously unattended locations. The results suggest an important link between the two phenomena and provide new insights into the brain mechanisms underlying visual attention and eye movements.     

聚合酶链反应检测疱疹Ⅱ型病毒先天性宫内感染的研究

以人工合成的单纯疱症Ⅱ型病毒DNA多聚基因片段为引物，采用聚合酶链反应技术(PCR)检查早孕绒毛标本中疤疹I型病毒感染，以80例自发和人工流产的早孕绒毛组织标本进行基因扩增，31例绒毛标本中检出HSV—Ⅱ，并与同一绒毛标本的免疫组织化学结果进行比较，PCR技术免除了昂贵繁杂的分子杂交过程，具有极高的敏感和特异性，为早期、快速产前诊断HSV先天性宫内感染的最佳技术。     

Modelling HA protein-mediated interaction between an influenza virus and a healthy cell: pre-fusion membrane deformation.

We present a mathematical model for pre-fusion interaction between an influenza virus and a healthy cell. Our model describes the role played by hemagglutinin (HA) protein clusters in bringing the viral membrane into close contact with the host cell membrane as a first step of the fusion process between the two membranes. The viral membrane is modelled as a lipid bilayer with bending rigidity. Using the calculus of variations, we compute the deformation of the viral membrane under the influence of HA protein clusters. Our numerical results support the hypothesis of dimple formation in the fusion site proposed in the literature. The asymmetric nature of the protein molecules due to various reasons such as tilting is the primary cause for the dimple formation. We discuss the effects of spontaneous curvature, the protein cluster radius, fusion-site size and the bending moment exerted by the protein cluster. We also examine the effects of membrane tension and the presence of a host cell on the dimple shape. Our results support previous experimental observations.     

RESPONSE CONTINGENCY AND HUMAN GASTRIC ACIDITY

The purpose of this study was to investigate the relationship between avoidance behavior of human subjects and gastric acid changes. An intragastric radio transmitter was employed to record stomach acid secretion rates. The subjects were divided into two groups. The members of the Response-Contingent (RC) group were led to believe that they would be able to avoid a strong electric shock during the Test phase of their session. In the No-Response (NR) group, subjects were correctly told that they would be without means of avoiding shock. The results demonstrated that (a) subjects could not be differentiated according to gastric acid secretion rate strictly on the basis of whether or not they made an avoidance response to an aversive stimulus; (b) a non-significant majority of subjects in both groups exhibited decreased gastric acid secretion rates during the Test phase; and (c) both groups showed a significantly faster rate of gastric acid secretion during the Post-Test phase than during the Test condition.