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41.
饮食性缺铜、缺锌对小鼠细胞因子产生的影响 总被引:1,自引:0,他引:1
3周龄小鼠饲用6周缺铜饮食后,出现胸腺萎缩、肝脏肿大以及明显的缺铜指征,包括血清Cp活性、肝Cu含量、CCO和Cu,Zn-SOD活性明显下降。缺钢小鼠产生的TNF-α、IL-1和IL-6水平明显低于正常组小鼠。小鼠饲予7周缺锌饮食后,出现明显脱毛,虽然肝Zn含量降低不明显,但TNF-α、IL-1和IL-6活性明显降低,说明上述细胞因子是小鼠缺锌的敏感指征之一。本文结果显示正常Cu、Zn水平对TNF-α、IL-1和IL-6产生的重要性,并提示这些细胞因子的改变可能是缺铜、缺锌引起的免疫功能损害的细胞、分子学机理之一。 相似文献
42.
目的构建α干扰素基因家族定向文库。方法利用D NAshuffling技术对人、鸡和猪α干扰素基因进行人工改造,结合噬菌体展示技术构建噬菌体基因改组文库,并对文库进行验证。结果构建了α干扰素基因家族定向文库,其容量为3.5×10^7pfu;测序得到了3条与猪、人α干扰素基因高度同源的序列。结论得到了1个高质量的α干扰素基因家族定向文库,为今后筛选高效的α干扰素奠定了基础。 相似文献
43.
Influence of antibody and complement components on phagocytosis and chemiluminescence of macrophages
Macrophages are known to release reactive oxygen species (O2?, 1O2, H2O2, OH·) in response to various membrane stimuliHowever, our studies show that phagocytic stimulation of macrophages is not necessarily accompanied by a stimulation of the oxidative burstWhereas IgG-opsonized erythrocytes were capable to induce phagocytosis and a chemiluminescence response, both being dependent on the number of IgG bound per erythrocyte, C3b-bearing erythrocytes were well ingested but failed to induce any chemiluminescence reactionFurthermore, stimulation of macrophages, via the Fc-receptors, seems to alter their functional state in regard to the activation of a receptor, which enables them to recognize membrane lesions on the target erythrocyteThe presence of IgG and membrane lesions, e.gthe C5b-9-complex of complement, induced a marked increase in chemiluminescence compared with stimulation by IgG-bearing particles aloneThe augmented response of macrophages was at least in part due to an additional release of H2O2, which was not liberated in response to IgG-bearing erythrocytesThis «Alesion recognizing receptor» in the macrophage membrane could not be activated by stimulation of C3b-receptors, indicating its functional linkage to the Fc-receptors. 相似文献
44.
Increased Mycobacterium tuberculosis growth in HIV-1-infected human macrophages: role of tumour necrosis factor-alpha 下载免费PDF全文
Imperiali FG Zaninoni A La Maestra L Tarsia P Blasi F Barcellini W 《Clinical and experimental immunology》2001,123(3):435-442
Synergism between Mycobacterium tuberculosis (M. tuberculosis) and HIV-1 infections was demonstrated in several in vitro models and clinical studies. Here, we investigated their reciprocal effects on growth in chronically HIV-1-infected promonocytic U1 cells and in acutely infected monocyte-derived macrophages (MDM). Phagocytosis of M. tuberculosis induced HIV-1 expression in U1 cells, together with increased TNF-alpha production. M. tuberculosis growth, evaluated by competitive PCR, was greater in HIV-1-infected MDM compared to uninfected cells. M. tuberculosis phagocytosis induced greater TNF-alpha and IL-10 production in HIV-1-infected MDM than in uninfected cells. In uninfected MDM, addition of TNF-alpha and IFN-gamma decreased, whereas IL-10 increased M. tuberculosis growth. On the contrary, in HIV-1-infected MDM, addition of TNF-alpha and IFN-gamma increased, whereas IL-10 has no effect on M. tuberculosis growth. TNF-alpha seems to play a pivotal role in the enhanced M. tuberculosis growth observed in HIV-1-infected MDM, being unable to exert its physiological antimycobacterial activity. Here, for the first time we demonstrated an enhanced M. tuberculosis growth in HIV-1-infected MDM, in line with the observed clinical synergism between the two infections. 相似文献
45.
A distinct pattern of cytokine production from blood mononuclear cells in multitransfused patients with β-thalassaemia 下载免费PDF全文
The unstimulated and induced production of granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), IL-3, IL-6, stem cell factor (SCF), IL-1β, tumour necrosis factor-alpha (TNF-α), TNF-β, interferon-gamma (IFN-γ) and transforming growth factor-beta (TGF-β) was determined after culture of blood mononuclear cells from 22 patients with severe β-thalassaemia in a regular transfusion programme, five non-regularly transfused patients with β-thalassaemia intermedia and nine normal persons. A distinct pattern of cytokine production in thalassaemic patients was detected, namely a low unstimulated production of all cytokines and a significant increase in the stimulated production of IFN-γ, TNF-α and IL-1β; these abnormalities were more pronounced in the more heavily transfused older patients. The increased production of the above cytokines, which usually characterize the acute response to infectious agents and have a negative effect on erythropoiesis, may explain the deterioration of anaemia found in thalassaemic patients during acute infections. 相似文献
46.
目的:研究针刺对多囊卵巢综合征(PCOS)大鼠卵巢转化生长因子α(TGF-α)、表皮生长因子受体(EGFR)表达的影响,探讨针刺促排卵的作用机制。方法:24日龄雌性大鼠颈背部皮下注射脱氢表雄酮(DHEA)的油溶液制作(PCOS)模型,对照组同期皮下注射油剂。PCOS大鼠随机分为模型组和针刺组。模型组不作处理,针刺组大鼠从80日龄起针刺关元、中极、双侧三阴交、双侧子宫穴,1次/天,15min/次,连续6周。治疗结束后各组大鼠断头处死,迅速取血并分离血清,-20℃冰箱保存,待测性激素水平。摘取双侧卵巢,称重,4%多聚甲醛固定,作HE染色和免疫组织化学染色。结果:与模型组相比,针刺组卵巢湿重、卵巢TGF-α、EGFR表达及血清睾酮(T)、雌二醇(E2)水平均显著降低(P<0.01),而卵泡刺激素(FSH)、黄体生成素(LH)、孕酮(P4)水平差异无统计学意义(P>0.05)。结论:针刺能显著降低PCOS大鼠卵巢TGF-α及EGFR的表达,抑制TGF-α对卵巢和激素合成的作用,改善PCOS大鼠多囊样变和高雄激素血症,促进排卵。 相似文献
47.
Kokkali G Vrettou C Traeger-Synodinos J Jones GM Cram DS Stavrou D Trounson AO Kanavakis E Pantos K 《Human reproduction (Oxford, England)》2005,20(7):1855-1859
PGD is a well accepted reproductive choice for couples at genetic risk and involves the diagnosis and transfer of unaffected IVF embryos. PGD for monogenetic diseases is most commonly accomplished by the biopsy of one or two blastomeres from cleavage stage embryos, followed by PCR-based protocols. However, PCR-based DNA analysis of one or two cells is subject to several problems, including total PCR failure, or failure of one allele to amplify. Trophectoderm biopsy at the blastocyst stage enables the removal of more than two cells for diagnosis while being non-invasive to the inner cell mass which is destined for fetal development. The aim of this study was to develop a safe, reliable technique for the biopsy of trophectoderm cells from human blastocysts. This case report demonstrates that removal of trophectoderm cells prior to blastocyst transfer is compatible with implantation and development to term. Here we report successful PGD for beta-thalassaemia following trophectoderm cell biopsy from blastocysts and the birth of a healthy infant. 相似文献
48.
Expression of alpha-methylacyl-CoA racemase (P504s) in various malignant neoplasms and normal tissues: astudy of 761 cases 总被引:3,自引:0,他引:3
Jiang Z Fanger GR Woda BA Banner BF Algate P Dresser K Xu J Chu PG 《Human pathology》2003,34(8):792-796
Alpha-methylacyl CoA racemase (AMACR), also known as P504S, plays an important role in peroxisomal beta-oxidation of branched-chain fatty acids. It has recently been shown that AMACR is highly expressed in prostate cancer and that it may be an important diagnostic marker for prostate carcinoma. However, little is known about expression of AMACR in normal tissues and other malignant tumors. In this study, we investigated expression of AMACR in 539 malignant tumors and 222 normal human tissues of various types by immunohistochemical analysis. mRNA levels of AMACR in normal organs and in selected tumors were assessed by real time PCR. In normal tissue, high expression of AMACR mRNA was identified in liver, kidney and salivary gland, while AMACR protein was detected in liver (hepatocytes), kidney (tubular epithelial cells), lung (only bronchial epithelial cells), and gallbladder (only mucosal epithelial cells). High expression of AMACR mRNA was found in prostate, liver, and kidney cancers but rarely in stomach and bladder cancers. A high percent of adenocarcinomas arising from these organs express AMACR, including 17 of 21 (81%) of hepatocellular carcinomas and 18 of 24 (75%) of renal cell carcinomas. In addition, carcinomas arising from tissues normally not expressing AMACR were also positive for the antigen, including 17 of 18 (94%) prostate carcinomas, 9 of 29 (31%) of urothelial carcinomas, and 4 of 15 (27%) of gastric adenocarcinomas. Two hundred and fifty cases of adenocarcinomas from lung, breast, pancreas, bile duct, adrenal gland, salivary gland, ovary, thyroid and endometrium were negative or rarely positive for AMACR. Neuroendocrine carcinomas rarely expressed AMACR. Melanomas, squamous cell carcinomas, basal cell carcinomas, soft tissue tumors (including epithelioid sarcomas and synovial sarcoma), thymomas, and germ cell tumors were negative for AMACR. Our data provide important baseline information for using AMACR in clinical practice and also are valuable in furthering understanding of the pathogenic role of AMACR in malignant neoplasms. 相似文献
49.
Juvenile dermatomyositis (JDM) is the most common pediatric inflammatory myopathy. In patients with JDM, the A --> G polymorphism in the tumor necrosis factor alpha (TNFalpha)-308 promoter region (TNFalpha-308A) is associated with prolonged disease course and increased production of TNFalpha by peripheral blood mononuclear cells (Arthritis Rheum. 43, 2368-2377, 2000). Magnetic resonance imaging directed biopsies from 21 white children with untreated JDM were evaluated for TNFalpha expression. Using monoclonal antibody to TNFalpha, fresh frozen sections were processed by the standard immunohistochemical technique. We investigated the association among the expression of TNFalpha by muscle fibers, disease activity, duration of untreated disease, and the TNFalpha-308 polymorphism. Untreated children with JDM who had the TNFalpha-308A allele had an increased number of TNFalpha stained muscle fibers than children with the TNFalpha-308G allele (P = 0.001). There was no association with disease activity or duration of untreated disease. We speculate that muscle fiber production of TNFalpha provides a microenvironment in which TNFalpha acts synergistically with other mediators to prolong muscle fiber damage. 相似文献
50.