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991.
Gupta GS Syal N 《American journal of reproductive immunology (New York, N.Y. : 1989)》2000,44(5):303-309
PROBLEM: In a previous study, mouse lactate dehydrogenase-C4 (LDH-C4) after chemical modifications with gossypol (Gossy-LDH-C4) and glucosylation with lactose (Glu-LDH-C4) was found to induce high immunological infertility in allogenic mice. In the present study, the characterization of antibodies and cross reactivity of the antisera produced against Gossy- and Glu-LDH-C4 with purified somatic isozymes are being reported. METHODS: Allo-antisera generated in Balb/c mice (i.r. route) against one primary (50 microg) and two secondary doses (30 x 2 microg) in Al(OH)3 were tested for cross-reactivity by ELISA and antibody avidity using Scatchard plot and Sip's plot. RESULTS: Results suggested that IgG against native LDH-C4 failed to recognize somatic isozyme, while antisera against chemically modified LDH-C4 consistently reacted with purified LDH from kidney and placenta. Scatchard plots and antibody saturation curves of native and complexed LDH supported the presence of heterogenous antibodies with a mean association constant (Ka) of the order of 10(6)-10(7) M(-1), whereas diversity of heterogeneity, defined by diversity constant (a), ranged between 0.89 and 1.23. In general, anti-Glu-LDH-C4 antiserum and native LDH-C4. reacted with higher Ka (low affinity) with a diversity constant of 0.89 compared with interaction between native LDH-C4 and it's antibodies. CONCLUSIONS: It is concluded that LDH-C4 is not an immunochemically sperm-specific protein, in which crossreactive epitopes are hidden within its conformation. Due to the large intake of cotton seed (a source of gossypol) by cattle, its unrefined oil by humans in various parts of the world, and the prevelance of diabetic state all the world over, the present study warns of immunological consequences in situ following gossypol interaction and glucosylation of LDH and conformationally related proteins in circulation. 相似文献
992.
M. E. Morris G. V. Obrocea M. Avoli 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,109(1):71-82
Transient changes in extracellular potassium concentration ([K+]0) and field potentials were evoked by 4-aminopyridine (4-AP; 50–100 M) and recorded with ion-selective microelectrodes in CA1b, CA3b and dentate sectors of adult rat hippocampal slices. Long-lasting field potentials recurred at a frequency of 1/60 s (0.016±0.003 Hz) in association with increases in [K+]0 which were largest and most sustained in the dendritic regions where afferent fibers terminate (dentate>CAl>CA3) and in the hilus. In stratum radiatum of CA1 or stratum moleculare of the dentate these fields had a peak amplitude of 1.4±0.29 mV, duration 8.3±1.6 s, and were accompanied by increases in [K+]0 of 1.8±0.22 mM that lasted 32±5.5 s (n = 17 slices). Interictal epileptiform potentials, which were brief (<0.2 s) and more frequent at 1/3 s (0.30±0.02 Hz) were also present in CA1, CA3 and the hilus and associated with small increases in [K+]0 (0.5 mM, duration 2 s). Interictal activity was blocked by 6-cyano-7-nitroquinoxalone-2,3-dione (CNQX; 5–20 M); the slow, less frequent potentials were resistant to both CNQX and dl-2amino-5-phosphonovaleric acid (APV; 50 M) and reversibly blocked (or attenuated by 80%) by bicuculline methiodide (BMI) (25–100 M). The BMI-sensitive potentials were also abolished by baclofen (100 M), an effect which was reversed by 2-OH-saclofen (100 M). Focal application of KCl or GABA in the absence of 4-AP evoked long-lasting field and [K+]0 potentials which were similar to those evoked by 4-AP but more sustained. The proportional relationship between the amplitudes of field and K+ potentials with GABA closely resembled that observed for 4-AP; in contrast the slope of KCl-evoked responses was lower. Our results demonstrate that in the adult rat hippocampus 4-AP induces in many different regions accumulations of [K+]0 in synchrony with the long-lasting field potentials, which are known to correspond to an intracellular long-lasting depolarization of the pyramidal cells. These changes are smaller than those which occur in the immature rat hippocampus — which may be related to differences in Na-K-ATPase and susceptibility to seizures. These events involve the activation of GABAA receptors, are under the modulatory control of GABAB receptors, and likely arise from the activity of GABAergic interneurons and/or afferent terminals. The long-lasting field potentials appear to reflect mainly the direct depolarizing actions of GABA and to a much more limited extent the associated accumulation of [K+]0. 相似文献
993.
五种免疫相关性心血管疾病的免疫学研究 总被引:4,自引:0,他引:4
对扩张型心肌病、风湿性心脏病,原发性高血压,冠心病及肥厚型心肌病进行外周血清可溶性白细胞介素2受体,T淋巴细胞亚群及自然杀伤细胞活性的检测,并与健康对照组比较,结果显示:DCM组,RHD组及EHT组的sIL-2R明显高于NC组,而DCM、RHD风湿活动组的NK活性低于NC组,EHT组NK活性高于NC组。 相似文献
994.
995.
L. J. Butler A. V. Palmer T. Spencer R. Tabios-Broadway W. J. Wall 《Clinical genetics》1987,31(4):199-205
A female child is described with multiple anomalies including epicanthus, frontal bossing, short sternum, polydactyly, cleft of the larynx, renal cysts, and unusual dermatoglyphics. She died aged 3 months and was found to have a unique de novo deletion of chromosome No. 4 (q22-q25). This case is compared with other long arm deletions of 4q and reference made to assignment of genetic markers to chromosome No. 4. 相似文献
996.
白细胞介素4基因转移的肿瘤细胞体外生物学特性及体内致瘤性的研究 总被引:2,自引:1,他引:2
观察了白细胞介素4(IL-4)基因转移的肿瘤细胞体内致瘤性的变化。构建了含500bp的小鼠IL-4cDNA的真核表达载体BMGNeo-IL-4.用该表达载体将IL-4基因转移至小鼠B16黑色素瘤细胞,通过G418抗性筛选、有限稀释法及IL-4活性检测,获得了高分泌IL-4的黑色素瘤细胞克隆株并经Northern印迹鉴定,将其接种于小鼠皮下后观察到肿瘤生长缓慢、小鼠存活期延长,表明高分泌IL-4的细胞克隆株体内致瘤性显著下降。该结果为进一步研究肿瘤的IL-4基因治疗打下了基础。 相似文献
997.
998.
目的:探讨半叶马尾藻多糖(SHP)拮抗辐射损伤小鼠造血系统的机制。方法:流式细胞术检测小鼠骨髓细胞周期和Westernblotting测定细胞周期相关蛋白质CDK4的表达。结果:[60Co]γ射线(5Gy)导致小鼠骨髓细胞G0/G1期阻滞,而S期和G2/M期细胞百分率下降。SHP(10-40mg/kg)可以减轻小鼠骨髓细胞G0/G1期阻滞,增加S期和G2/M期细胞百分率,表现为SHP加照射组小鼠G0/G1期骨髓细胞百分率明显低于单纯照射组,S期和G2/M期骨髓细胞百分率显著高于单纯照射组。小鼠骨髓细胞CDK4蛋白质表达照射组明显低于正常对照组,SHP加照射组小鼠骨髓细胞CDK4蛋白质表达显著高于单纯照射组。结论:SHP拮抗[60Co]γ射线损伤小鼠骨髓细胞的机制与其调节骨髓细胞周期和增加CDK4蛋白质表达密切相关。 相似文献
999.
以4型腺病毒疫苗株感染A549细胞,提取病毒DNA,将EcoRI消化的D片段(70.5-83.0基因图谱单位)克隆入pUC18质粒,得pAd4(70.5-83)质粒,质粒pAd4(70.5-83)和pAd4C1-25经酶切、系列亚克隆、加接头等方法得到大部分和部分缺失E3区的重组质粒。聚合酶链反应(PCR)法获得poly(A),构建约800bP腺病毒晚期表达盒,在所构建的腺病毒重组质粒E3缺失区或E4与ITR间插入表达盒,得到可同时表达2个或2个以上外源基因和保留了E3区编码分子量为19300糖蛋白基因的3种Ad4载体。将lacZ基因插入载体表达区,与Bell消化的Ad4DNAA片段共转染A549细胞,ONPG法检测证实所构建的载体和表达盒功能良好。本项工作对于在国内研究口服活疫苗及开展基因治疗均具有重要意义。 相似文献
1000.
Functional expression of 4-1BB (CD137) in the inflammatory tissue in Crohn's disease 总被引:2,自引:0,他引:2
Maerten P Geboes K De Hertogh G Shen C Cadot P Bullens DM Van Assche G Penninckx F Rutgeerts P Ceuppens JL 《Clinical immunology (Orlando, Fla.)》2004,112(3):239-246
4-1BB ligand (L) expressed on antigen presenting cells (APC) interacts with 4-1BB, expressed on activated T cells and this interaction costimulates T cells to secrete cytokines and to proliferate. We investigated whether 4-1BB/4-1BBL interactions might be involved in the pathogenesis of Crohn's disease (CD). In immunohistochemistry, we found 4-1BB expression on lamina propria (LP) cells in inflamed and to a lesser extend in non-inflamed gut tissue from CD patients. mRNA levels for 4-1BB were also elevated in intestinal CD tissue. In contrast, only few 4-1BB-expressing cells were found in inflamed tissue from ulcerative colitis (UC) patients and almost no positive cells were found in control intestinal tissue. 4-1BB expression was better sustained on in vitro activated lamina propria T cells from CD patients compared to controls. Finally, agonistic anti-4-1BB antibody enhanced interferon-gamma (IFN-gamma) production and proliferation of lamina propria T cells from CD patients. Taken together, our data suggest that 4-1BB/4-1BBL interactions contribute to the persistence of gut inflammation in CD. 相似文献