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41.
Recent studies suggest that abnormalities occur at the lipid level in malignant hyperthermia susceptible humans and pigs. To test this hypothesis, we first investigated the physical state of plasma membranes of lymphocytes isolated from normal and malignant hyperthermia susceptible swine. In halothane-challenged pigs, malignant hyperthermia susceptibility was also assessed by ryanodine binding assay on purified sarcoplasmic reticulum membranes. The results clearly show that plasma membrane of lymphocytes from malignant hyperthermic pigs are significantly more fluid than controls. We then attempted to apply the same methodology to lymphocytes prepared from human patients previously diagnosed by the halothane and caffeine contracture test. In that case, there was no clear relationship between malignant hyperthermia susceptibility and the fluidity state of lymphocyte plasma membranes. 相似文献
42.
43.
本文收集了我省十年(1974—1983)来诊断为恶性淋巴瘤的病例,按免疫功能分类复查了全部切片,最后确诊为非何杰金氏恶性淋巴瘤(NHL)528例,进行了分析。本组NHL在首发部位、类型分布等方面与国内外有所不同。本组NHL首发于淋巴结外的占64.02%,明显高于国内其它省、市,而滤泡型淋巴瘤则低于国内多数地区。T细胞淋巴瘤占14.84%,较国内、外均低。并提出提高制片质量和广泛开展及应用免疫学技术的重要性。 相似文献
44.
Benjamin Sadlack Ralf Kühn Hubert Schorle Klaus Rajewsky Werner Müller Ivan Horak 《European journal of immunology》1994,24(1):281-284
Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice. 相似文献
45.
在体外试验中研究了azimexon对小鼠脾细胞增殖以及白细胞介素2(IL-2)的影响。IL-2活性采用小鼠胸腺细胞增殖法和CTLL细胞增殖法测定。结果表明:azimexon单独不能增加脾细胞增殖和产生IL-2,但对亚适量ConA或LPS诱导的脾细胞增殖和产生IL-2有明显协同作用。 相似文献
46.
Mitsuhiko Yanagisawa M.D. 《Pediatrics international》1987,29(6):815-823
Using spontaneously established autologous lymphoblastoid B cell lines (LCL), killer cell activities were studied in children with severe infectious mononucleosis (IM), chronic IM, and acute IM, and compared with those in EBV-seropositive normal controls. Natural killer (NK) cell activity of fresh peripheral blood mononuclear cells (PBMC) was normal in acute IM patients, but it was low in four of six patients with severe or chronic IM. Recombinant inter-leukin 2 (rIL-2)-activated PBMC from normal controls showed lymphokine-activated killer (LAK) cell activity against the respective autologous LCL. The levels of LCL lysis by LAK cells were significantly higher in acute IM patients, lower in chronic IM patients, and much lower in severe IM patients. In contrast to the fact that PBMC stimulated in vitro with autologous LCL (IVS cells) from normal controls and acute IM patients showed potent killing of autologous LCL, IVS cells from severe or chronic IM patients showed lower levels of LCL lysis, which were markedly augmented in three patients by rIL-2 addition to the cultures. These killer cell dysfunctions appear to be responsible for the severe or chronic course of EBV infection. 相似文献
47.
Peripheral blood CD3 and CD4 T-lymphocyte reduction correlates with severity of liver cirrhosis 总被引:2,自引:0,他引:2
L. Lombardo A. Capaldi G. Poccardi P. Vineis 《International Journal of Clinical & Laboratory Research》1995,25(3):153-156
Summary Immunological disturbances with impairment of immune function and a higher incidence of lymphoproliferative disorders and
other malignancies have been described in liver cirrhosis patients. To investigate the pathogenetic mechanism(s) involved
in such associated we looked for a possible imbalance in peripheral blood T-lymphocyte subpopulations in patients with liver
cirrhosis of differing severity. Immunophenotyping and counts of peripheral blood T-lymphocyte subpopulations were carried
out using monoclonal antibodies conjugated with different fluorochromes in 31 consecutive cirrhotic patients and 23 matched
healthy volunteers. Univariate and multivariate analyses of lymphocyte phenotype counts were performed and odds ratios were
computed. Statistically significant associations, according to both univariate and multivariate analyses, were found between
case/control status and mean CD3 and CD4 T-lymphocyte counts (P<0.0001). A strong correlation was found between the Pugh’s index and CD3 and CD4 lymphocyte counts, with a clear reduction
of these phenotypes with increasing liver cirrhosis. Median CD3 and CD4 values were 2,283 and 1,329/μl respectively among
controls and 896, 801, and 492/μl and 515, 514, and 307/μl, respectively in categories A, B, and C of Pugh’s classification.
Very high odds ratios were found using the median values of CD3 and CD4 as a threshold. There was a statistically significant
decrease for each of the T-cell phenotypes studied (CD2, CD3, CD4, CD8, CD16, CD19, CD20, CD56, CD57) between patients and
controls (P<0.0001). The progressive and severity-related decrease in mean peripheral blood CD3 and CD4 counts in liver cirrhosis suggests
a progressive impairment of protective immune function and may be a factor facilitating malignancy in cirrhotic patients. 相似文献
48.
研究了辐射诱发的人外周血淋巴细胞凋亡生成,以及水溶性维生素E类似物-Trolox对辐射诱导人外周血淋巴细胞凋亡的抑制作用。照后30分钟内Trolox能有效地阻抑DNA片段形成,而在照前或受照中加入Trolox均不能抑制DNA片段形成,揭示Trolox并不是通过清除照射过程中产生的自由基而起作用。照后30分钟内加Trolox,2小时后撤去,同样能抑制DNA片段形成,表明Trolox能不可逆地阻抑细胞凋亡早期的"关键"事件。 相似文献
49.
Yannick Poquet Patricia Constant Franck Halary Marie-Alix Peyrat Martine Gilleron François Davodeau Marc Bonneville Jean-Jacques Fournié 《European journal of immunology》1996,26(10):2344-2349
The stimulation of human γδ T cells by mycobacteria occurs through recognition of four distinct nonpeptide phosphorylated antigens termed TUBag1–4. Among these latter, TUBag4 has already been biochemically characterized as a γ-X derivative of 5′-deoxythymidine triphosphate (Constant, P., Davodeau, F., Peyrat, M. A., Poquet, Y., Puzo, G., Bonneville, M. and Fournié, J.-J., Science 1994. 264: 267). However, despite chemical synthesis of weakly stimulatory nucleotide-containing analogs, these mycobacterial compounds remained the sole nucleotide-containing antigens actually isolated from natural sources. Here, we present the complete isolation of the TUBag3 antigen from Mycobacterium fortuitum and demonstrate that this nonpeptide molecule contains a 5′-UTP nucleotide moiety. On selected Vγ9/Vδ2 clones, T cell responses can be triggered with nanomolar concentrations of TUBag3. Like crude mycobacterial extracts, this purified nucleotide conjugate elicits a strong polyclonal response of γδ PBL from healthy donors. Furthermore, we present evidence that this compound is distinct from the recently synthesized γ-isopentenyl 5′-UTP, a nucleotide conjugate of isopentenyl pyrophosphate that was found to be stimulatory for human γδ T cells (Tanaka, Y., Morita, C. T., Tanaka, Y., Nieves, E., Brenner, M. B. and Bloom, B. R., Nature 1995. 375: 155). Since it appears that both mycobacterial nucleotide antigens are molecules structurally related to peculiar precursors of nucleic acid synthesis, we propose that TUBag-reactive T cells might be specifically devoted to surveillance of proliferating cells. 相似文献
50.
Choremi-Papadopoulou H Tsalimalma K Dafni U Dimitracopoulou A Kordossis T 《Journal of medical virology》2004,73(2):235-243
Long-term (3.5 years) immune reconstitution in relation to viral load response was determined. Plasma HIV-1 RNA was suppressed in 40 patients (full responders) up to 42 months, and 17 patients achieved partial response. The measurements of CD4+ and CD8+ T lymphocyte subsets (CD45RA, CD45RACD62L, CD45RO, CD28, CD38) were carried out by flow cytometry. Full responders had a significant increase of CD4+ and all CD4+ T subsets both up to 6 and from 6 to 42 months, while the increase for partial responders was only up to 6 months. By 6 months, higher slopes were observed in full versus partial responders in the % of CD28 on CD4+ and the % of CD4+ memory subset and in both naïve and memory CD4+ subsets from 6 to 42 months. The percentage of CD8+ and its subsets was decreased significantly in full responders both up to 6 and from 6 to 42 months (except for an increase in the CD8+CD45RA+ CD62L+ cells), while in partial responders this decrease was only up to 6 months. Lower slopes were observed in full versus partial responders from 6 to 42 months in the percentages of CD8+, CD8+CD45RO+, CD8+CD28−, and CD8+CD38+ T cells. In conclusion, full responders have a stronger long-term naive CD4+ T cell subset reconstitution than partial responders. J. Med. Virol. 73:235–243, 2004. © 2004 Wiley-Liss, Inc. 相似文献