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991.
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
992.
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
993.
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
994.
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
995.
《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
996.
997.
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
998.
999.
1000.
Daniel F. Legler Marcel Loetscher Simon A. Jones Clemens A. Dahinden Michel Arock Bernhard Moser 《European journal of immunology》1996,26(4):753-758
The proteolytic cleavage product of complement component 3, (C3a), like C4a and C5a, is a potent anaphylatoxin and induces the production of inflammatory mediators in phagocytes. Notably, mast cells respond to C3a with the release of vasoactive substances, including histamine. We have examined the function and receptor binding of C3a in a human leukemic mast cell line, HMC-1. Similar to chemoattractant agonists in leukocytes, C3a induced rapid cytosolic free calcium concentration increases in HMC-1 cells. EGTA did not diminish this response, indicating that mobilizable Ca2+ was from intracellular stores. Receptors for C3a in HMC-1 cells couple in part to Bordetella pertussis toxin-sensitive G-proteins and, therefore, appear to belong to the family of serpentine receptors that require G-proteins for signal transduction. HMC-1 cells express two types of C3a receptors, C3aR1 and C3aR2, that were shown to bind 125I-C3a with high-(Kd1 = 2.1–4.8 nM) or low-affinity (Kd2 = 30–150 nM), and both receptors are expressed at high level: 3 × 105–6 × 105 C3aR1/cell and 5 × 105–2.3 × 106 C3aR2/cell. Results from cross-linking experiments with 125I-C3a fully agree with the presence of two different classes of C3a receptors in HMC-1 cells. Two membrane proteins with apparent molecular masses of 54–61 kDa (p57) and 86–107 kDa (p97) could be covalently modified with 125I-C3a, and this cross-linking was inhibited with an excess of unlabeled C3a. Many of the known agonists for leukocytes including 13 chemokines (IL-8, NAP-2, GROα, ENA-78, IP10, PF4, MCP-1, 2 and 3, RANTES, MIP-1α, MIP-1β and 1309), three neuropeptides (neuropeptide Y, somatostatin and calcitonin), as well as C5a, did not activate HMC-1 cells, indicating that C3a is one of a few protein ligands for which this cell line expresses specific receptors. The apparent selectivity for C3a and the abundant expression of C3a receptors make the HMC-1 cell line an excellent choice for the cloning of the receptor genes. 相似文献