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991.
本文探讨了5/6肾切除术后慢性肾衰大鼠残肾纤维化的发生机理,发现术后120天,在残肾单个核炎性细胞浸润、残肾显著纤维化和肾功能损害的同时,残肾脂质过氧化物含量显著升高,抗氧化机制功能显著下降,钠钾ATP酶活力显著下降,周围血单个核细胞内游离钙浓度显著升高,单个核细胞培养上清白介素-1活性增高。而摄入大量维生素E的大鼠,上述各指标有不同程度的改善,残肾纤维化显著减轻。提示残肾纤维化可能与单个核白细胞内游离钙浓度升高,进而产生白介素-1增多有关。 相似文献
992.
High frequency of spontaneous interferon-gamma-producing cells in human tonsils: role of local accessory cells and soluble factors. 总被引:1,自引:1,他引:1
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M Quiding G Granstrm I Nordstrm B Ferrua J Holmgren C Czerkinsky 《Clinical and experimental immunology》1993,91(1):157-163
The frequency of mononuclear cells (MNC) spontaneously secreting interferon-gamma (IFN-gamma) has been examined in freshly isolated cell suspensions from human palatine tonsils. Two-site reverse enzyme-linked immunospot (ELISPOT) analyses, involving short term (20 h) incubation of MNC in the absence of any added exogenous stimulus, revealed that tonsillar MNC suspensions contain exceptionally large numbers of cells secreting IFN-gamma. No significant differences were observed when comparing the frequency of IFN-gamma-producing cells between cell suspensions obtained from hyperplastic and tonsillitis specimens. Cell-sorting experiments disclosed that spontaneous tonsillar IFN-gamma production was essentially contributed by CD4+ T cells, and required the presence of accessory cells and/or soluble factors to be detected. Thus, depletion of plastic adherent cells or monocytes from the tonsillar MNC suspensions resulted in reduced numbers of detectable IFN-gamma-secreting cells. Addition of very small numbers of autologous monocytes restored spontaneous IFN-gamma production in tonsillar MNC cultures depleted of monocytes. Neutralization of endogenous IL-1 beta and IL-2, as well as blocking of the IL-2 receptor, also decreased IFN-gamma production from unfractionated tonsillar cells. Addition of exogenous IL-1 beta restored IFN-gamma production in cultures of tonsillar MNC depleted of plastic adherent cells. Furthermore, IL-1 beta synergized with IL-2 by tonsillar MNC depleted of plastic adherent cells. Furthermore, IL-1 beta synergized with IL-2 by increasing intracellular as well as cell-free levels of IFN-gamma in cultures of unfractionated tonsillar MNC. This study further establishes that the tonsils are highly active immunological organs containing large numbers of T cells spontaneously producing IFN-gamma whose detection is contingent upon the presence of functional accessory cells. It also demonstrates that concomitant production of IL-1 beta and IL-2 occurs in tonsils and is necessary to maintain ongoing synthesis and extracellular accumulation of IFN-gamma in these organs. 相似文献
993.
Immunoprecipitation of radiolabeled polypeptides from complex mixtures of proteins was performed in polystyrene microtiter plates using staphylococcus protein A and various antibody preparations. The method is (1) rapid, (2) uses multichannel micropipettor technology, (3) handles large numbers of specimen easily, (4) requires very small volumes of antigen and antibody (5–50 μl), (5) provides replicates for statistical analysis and (6) allows recovery of precipitated proteins for direct SDS-PAGE analysis of precipitated proteins. We have shown it is useful as a test to screen large numbers of sera or to characterize monoclonal antibody-containing samples. 相似文献
994.
P.-Y. Le Pennec F. Noizat-Pirenne M.T. Klein D. Fraval J.M. Lascaux Ph. Rouger 《Transfusion Clinique et Biologique》1996,3(6):401-404
In this paper we chose to emphasize three aspects of our work. First we underlined that “low grade and high grade” D weak red blood cells studied at the DNA level could, when monoclonal antibodies were used, give patterns of positive and negative reactions like partial RH1(D) cells. Secondly, we showed the importance of the technical conditions of the study which are essential for establishing a pattern of reactivity defining an epitope. It appears that the use of papain treated cells at room temperature can be misleading for the definition of epitope especially with IgM antibodies. Lastly we pointed out the interest of Rh variant cells, defined at the gene level, to study the expression of RH1(D) epitopes on the external part of the membrane. 相似文献
995.
Low interleukin-2 receptor levels in serum of patients with insulin-dependent diabetes 总被引:1,自引:0,他引:1
R. Wagner E. Bonifacio P. J. Bingley S. Genovese D. Reinwein G. F. Bottazzo 《Journal of molecular medicine (Berlin, Germany)》1994,72(7):494-498
Interleukin-2 receptors are released in the circulation in response to antigenic or mytogenic stimulation of T-lymphocytes. Abnormal serum interleukin-2 receptor levels have been found in young children with type 1 diabetes and prediabetes. We measured interleukin-2 receptor levels in 17 patients with newly diagnosed type 1 diabetes, 21 patients with long-standing type 1 diabetes, 19 patients with long-standing type 2 diabetes, 19 islet-cell antibody positive nondiabetic polyendocrine patients, 12 islet-cell antibody-positive first-degree relatives of patients with type 1 diabetes and compared the results to age- and sex-matched normal controls. We found significantly lower interleukin-2 receptor levels in patients with newly diagnosed and long-standing type 1 diabetes compared to normal controls (87 ± 11 and 93 ± 11 vs. 142 ± 25 and 132 ± 40 U/ml, P < 0.001 and P < 0.01). There were no significant differences in interleukin-2 receptor levels between prediabetic groups and normal controls or patients with long-standing type 1 or type 2 diabetes. There was no correlation between glycosylated hemoglobin, blood glucose levels, and interleukin-2 receptor in the groups with long-standing type 1 or type 2 diabetes. We conclude that patients with type 1 diabetes have low interleukin-2 receptor serum levels. This phenomenon is acquired close to disease onset and is unlikely to be an early markers of type 1 diabetes.Abbreviations JDf
Juvenile Diabetes foundation
- ICA+
islet-cell antibody positive
- IDDM
insulin-dependent diabetes mellitus
- IL-2R®
interleukin-2 receptors
- NIDDM
non-insulin-dependent diabetes mellitus
Correspondence to: R. Wagner 相似文献
996.
Malyak Mark Smith Michael F. Abel Ashley A. Arend William P. 《Journal of clinical immunology》1994,14(1):20-30
Journal of Clinical Immunology - The objective of this study was to characterize interleukin-1 receptor antagonist (IL-1ra) and interleukin-1β (IL-1β) production by human peripheral blood... 相似文献
997.
《The Knee》2022
BackgroundIn recent years, transcatheter arterial embolization (TAE) using imipenem/cilastatin (IPM/CS) has attracted attention as a treatment for relieving osteoarthritis (OA) pain. However, IPM/CS is not approved by Japanese medical insurance for use as an embolic material. Therefore, it is necessary to develop new embolic materials for TAE to relieve OA pain. The purpose of this study was to develop a swine model of knee arthritis and embolize abnormal neovessels (ANs) using two different embolic materials. We compared the embolic effects and tissue damage in knees.MethodsKnee arthritis was induced by intra-articular injection of papain into 12 knees in six female swine. The swine were divided into two groups of three swine each (six knees per group) for embolization of ANs in the knees with either IPM/CS or soluble gelatin sponge particles (SGSs). Three days after embolization, we compared the embolic effects using angiography and the tissue damage histopathologically.ResultsANs were observed in all 12 knees at 42 days after papain injection. The ANs disappeared and the patent arteries were recanalized 3 days after TAE in all 12 knees. Histopathological evaluation revealed synovitis changes, such as synovial thickening and inflammatory cell infiltration, in all 12 knees. There was no evidence of skin or muscle necrosis in either group. The appearance of ANs, recanalization of the parent arteries, and histopathological outcomes were not significantly different between the two groups.ConclusionSGSs were as safe as IPM/CS for TAE of ANs in this swine model of knee arthritis. 相似文献
998.
999.
目的: 研究腺病毒介导14-3-3·σ(Ad-14-3-3·σ)对Akt过表达Rat1-Akt细胞增殖的影响,并探讨其作用是否通过调控p27而实现。 方法: 通过5-溴-2′脱氧尿嘧啶(BrdU)实验检测Ad-14-3-3·σ对Rat1-Akt细胞增殖的影响,并通过激酶分析法和免疫荧光实验探讨Ad-14-3-3·σ对p27磷酸化水平及其在细胞内定位的影响。 结果: Ad-14-3-3σ转染的细胞BrdU阳性率(45%)低于PBS处理组(100%)或Ad-β-gal转染的对照组细胞(98%)。14-3-3σ可降低磷酸化p27的水平和减少Akt介导的p27在胞浆中的定位。 结论: 转染14-3-3σ基因能抑制Akt过表达细胞株Rat1-Akt增殖,14-3-3σ通过降低Akt激酶磷酸化p27的活性,阻断Akt介导的p27胞浆错位,从而发挥其抑制Rat1-Akt细胞增殖。 相似文献
1000.