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71.
内皮细胞生长因子诱导大鼠血管内皮细胞增殖过程中FKBP12的表达 总被引:1,自引:1,他引:0
目的探讨内皮细胞生长因子(Endothelial cell growth factor,ECGF)诱导的血管内皮细胞(Vascular endothelial cell,VEC)增殖过程中FK506结合蛋白12(FK506 binding protein 12,FKBP12)表达的变化,为VEC的鉴定提供新的方法。方法培养大鼠VEC并传代。倒置显微镜下观察其在ECGF作用下的增殖情况,检测Ⅷ因子相关抗原、FKBP12和不同时期FKBP12 mRNA水平的表达。结果VEC表达FKBP12;VEC传代后第4天FKBP12 mRNA表达水平达到最高,6—8d下降。结论FKBP12既可作为VEC的标志物,又可反映VEC的增殖情况。 相似文献
72.
白细胞介素-12基因修饰对树突状细胞表面分子表达及细胞因子分泌的影响 总被引:1,自引:0,他引:1
目的 观察白细胞介素(IL)-12基因修饰对树突状细胞(DC)表面分子及细胞因子分泌的影响.方法 采用重组逆转录病毒介导IL-12基因修饰人外周血单个核细胞(PBMC)来源的Dc;ELISA法检测各组DCs和各组T细胞上清中IL-12、IL-10、IFN-γ因子的分泌水平;流式细胞仪(FACS)分析各组DC表面CD83、CD86的表达;MTT法检测DC刺激同源T淋巴细胞增殖的能力;统计学分析比较各组间的差异.结果 IL-12基因修饰使得DC高表达CD83和CD86分子,分泌高水平IL-12及IFN-γ,但对IL-10因子的分泌无明显影响,刺激同源T淋巴细胞增殖明显,诱导激活的T细胞上清中IFN-γ水平显著增高、IL-10分泌水平显著降低.结论 经IL-12基因修饰后的DC表型成熟,分泌IL-12及IFN-γ的能力增强,对IL-10因子的分泌无影响,能抑制T细胞分泌IL-10因子,优化抗原提呈的微环境. 相似文献
73.
Tetsuji Fujita Katsuhiko Yanaga 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(2):127-130
BACKGROUND: Although there is increasing evidence suggesting that the vagus nerve functions as a connector between the nervous and immune systems in animals, little is known about the role of the vagus nerve in postoperative acute phase response in humans. MATERIALS AND METHODS: The extent of fever and acute phase protein response and the production of inflammatory cytokine during the early postoperative period were compared among the patients who had undergone total gastrectomy including truncal vagotomy (n = 13), those having distal gastrectomy with division of vagal branches (n = 14), and the patients with vagal nerve preserving gastrectomy (n = 12). RESULTS: There was no significant difference in serum levels of C-reactive protein, alpha-1-antirypsin, and interleukin-6 among the three groups. Also, postoperative maximum body temperature was similar. CONCLUSIONS: Vagotomy did not influence acute phase response after gastric cancer surgery. A multipathway mechanism for acute phase response including the induction of fever is suggested. 相似文献
74.
Biological properties of interleukin-12 and its therapeutic use in persistent hepatitis B virus and hepatitis C virus infection 总被引:2,自引:0,他引:2
Summary. Interleukin (IL)-12 is a pleiotropic cytokine produced by antigen-presenting cells in response to diverse stimuli. IL-12 is a key molecule in the regulation of host's immune responses. In particular, IL-12 influences the balance between the T-helper cells type 1 (TH1 ) and type 2 (TH2 ); it modulates macrophage responses through the control of interferon-gamma synthesis by TH1 cells; and, suppresses IgE class antibody production (has a suppressive effect on allergic reactions) and promotes a shift in the IgG subclasses. IL-12 enhances resistance to several infectious diseases, is a powerful antitumor agent in vivo , and acts as a vaccine adjuvant. The biological properties of IL-12 point to the potential therapeutic use in persistent hepatitis B virus and hepatitis C virus infection. 相似文献
75.
Marlon Normandin Joel Gagn Julie Bernard Robert lie Dom Miceli Michel Baudry Guy Massicotte 《Brain research》1996,730(1-2):40-46
Low-frequency stimulation is associated with long-term depression (LTD) of synaptic efficacy in various brain structures. Like long-term potentiation (LTP), homosynaptic LTD in area CA1 of the hippocampus appears to require NMDA receptor activation, changes in postsynaptic calcium concentration and phospholipase A2 (PLA2) activation. Arachidonic acid (AA) is released after the activation of calcium-dependent phospholipases and free AA is rapidly metabolized to a family of bioactive products (the eicosanoids) which are thought to be both intracellular and extracellular messengers. In the present study, we investigated the involvement of the cyclooxygenase and lipoxygenase pathways of AA metabolism in the formation of homosynaptic LTD in the rat hippocampus. Stimulation at 1 Hz for 15 min was used to produce homosynaptic depression in area CA1 of hippocampal slices. LTD induction was partially blocked by bromophenacyl bromide (50–100 μM), a selective PLA2 inhibitor, and by the a nonselective lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA; 100 μM). In contrast, the specific cyclooxygenase blocker indomethacin (100 μM) did not significantly reduce hippocampal LTD. Since NDGA interferes with LTD formation, we examined whether specific inhibitors of 5- and 12-lipoxygenases were capable of blocking LTD expression. The 12-lipoxygenase inhibitor baicalein at a concentration of 50 μM reduced LTP formation when given in the bath, an effect that was less pronounced with the 5-lipoxygenase inhibitor AA-861. These data suggest that the activation of endogenous PLA2 and the formation of 12-lipoxygenase metabolites of AA may be important factors controlling the expression of hippocampal LTD. 相似文献
76.
Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established
model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with
regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders
like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin
cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors.
One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The
experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the
putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed:
(1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic
sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla.
Accepted: 21 August 1996 相似文献
77.
L. Szereday p. Varga J. Szekeres-Bartho 《American journal of reproductive immunology (New York, N.Y. : 1989)》1997,38(6):418-422
PROBLEM: In the presence of progesterone lymphocytes of pregnant women release a 34- kDa protein named the progesterone-induced blocking factor (PIBF). PIBF mediates the immunomodulatory and anti-abortive effects of progesterone and its presence is related to the outcome of pregnancy. PIBF induces production of Th2 type cytokines by activated lymphocytes. The in vivo relationship between PIBF- and cytokine production of pregnancy lymphocytes and the outcome of pregnancy was investigated. METHOD OF STUDY: Interleukin (IL)-12 and IL-10 production and PIBF expression in peripheral lymphocytes of 111 healthy pregnant women and 120 women at risk for premature pregnancy termination were detected by immunocytochemistry. RESULTS: We found increased IL-12 and low PIBF and IL-10 expression on lymphocytes of “risk” patients, and a high rate of IL-10 and PIBF positivity on lymphocytes from healthy pregnant women. The cytokine production pattern of the lymphocytes was related to the presence or absence of previous abortions as well as to the outcome of pregnancy. CONCLUSION: These data suggest the involvement of an altered cytokine production pattern in the immunologic effects of progesterone. 相似文献
78.
Decorin, a collagen-binding small proteoglycan, is considered to have a specific function in the organization or stability of the collagen network. Therefore, alteration of its molecular properties may be of pathophysiological relevance during the development of cartilage damage. It is shown here that normal cartilage from rabbit knee-joint contains glycosaminoglycan chain-bearing core protein fragments of 39, 23, and 18 kDa, each one amounting to approximately 5-6% of the intact decorin core protein. Continuous infusion of human recombinant interleukin-1 alpha for 14 days (200 ng/day) into a knee-joint led in condylar cartilage to a reduction in the amount of intact core protein from 2 micrograms/mg wet tissue to about 1.1 micrograms/mg. The increase in its quantity found after infusion of heat-inactivated interleukin-1 was not statistically significant. The concentration of all three core protein fragments became reduced to a similar extent as the intact core protein under the influence of the cytokine, and additional fragments were not found. Surprisingly, there was a much smaller response to interleukin-1-treatment in patellar cartilage. 相似文献
79.
Shi Yong Ryu Chong-Kyo Lee Chong Ock Lee Hae Soo Kim Ok Pyo Zee 《Archives of pharmacal research》1992,15(3):242-245
Two triterpenes 1 and 2 with antiviral activity againstHerpes simplex virus type 1in vitro were isolated fromPrunella vulgaris. Each compound caused a significant reduction in viral cytopathic effect whenvero cells were exposed to them for 72 hours after viral challenge. They were identified asbetulinic acid(1) and 2α, 3α-dihydroxyurs-12-en-28-oic acid(2) on the basis of their spectroscopic properties. The antiviral activity of them was estimated as EC50=30 μg/ml(1) and 8 μg/ml(2), respectively by plaque reduction assay. 相似文献
80.
《Movement disorders》2003,18(11):1240-1249
The identification of disease genes using family‐based approaches has provided important insights into the pathogenesis of Parkinson's disease (PD) demonstrating the importance of genetic studies on monogenic forms of the disease. We studied a large Cuban family with typical, late‐onset PD and probable autosomal dominant inheritance. Mean age at onset was 61.2 years (±12.53, 45–76). Other phenotypes such as essential tremor and atypical parkinsonism were observed in this family. We carried out a genome‐wide scan and linkage analyses. The genetic data were analyzed using a conservative model in which only patients with clinically definite or likely PD were considered affected, other phenotypes were regarded as “unknown.” Multipoint analyses yielded a maximum LOD of 2.26 between markers D19S221 and D19S840. Haplotype analysis showed a region on chromosome 19 shared by six of seven PD patients. The essential tremor phenotype and the atypical parkinsonism do not segregate with this haplotype, suggesting a different etiology. Our findings suggest the presence of a novel locus for PD on chromosome 19p13.3–q12. We propose that an oligogenic model with moderate contribution of two or three genes rather than a “pure” monogenic model might explain better the wide range in age at onset, the reduced penetrance and the phenotypical variability observed in PD families. © 2003 Movement Disorder Society 相似文献