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101.
Identification and characterization of a DR4-restricted T cell epitope within chlamydia heat shock protein 60 总被引:11,自引:0,他引:11 下载免费PDF全文
K H O DEANE R M JECOCK J H PEARCE J S H GASTON 《Clinical and experimental immunology》1997,109(3):439-445
An epitope within the 60 kD Chlamydia trachomatis heat shock protein (hsp) 60, recognized by a HLA-DRB1*0401-restricted T cell clone from a reactive arthritis patient, has been characterized. Stimulatory peptides contained a nine amino acid sequence (residues 38–46) predicted by algorithm to confer strong binding to DRB1*0401, with valine in the P1 position. The overall length of the peptide was critical for efficient recognition; peptides with at least one residue N-terminal to the putative P1 position were markedly more stimulatory than a peptide whose N-terminal is the P1 valine. Optimal responses were seen with 14mer peptides having two to three amino acids N- and C-terminal to the core 9mer. The sequence of the defined epitope is identical in hsp60 from both C. trachomatis and C. pneumoniae. Since the latter is a common respiratory pathogen, patients infected with C. trachomatis may already be primed for responses to hsp60 by prior infection with C. pneumoniae. Such secondary responses are important in the pathogenesis of chlamydia-induced inflammatory diseases such as trachoma. Priming by infection with enteric organisms was considered because of the similarity of the epitope sequence in Escherichia coli hsp60. However, although an E. coli-related peptide was recognized, intact E. coli hsp60 was not, suggesting that the epitope is cryptic in E. coli hsp60. Human hsp60 has six amino acid differences from chlamydial hsp60 in the epitope sequence and was not recognized. Thus cross-reactive recognition of self hsp60 could not be implicated in the pathogenesis of chlamydia-induced reactive arthritis in this patient. 相似文献
102.
Objective: To compare the safety and efficacy of two compounds of dihydroartemisinin(DHA) -Artekin and Artekin (T) in the treatment of uncomplicated falciparum malaria. Methods:The regimen of 8-tablet for 2 days of Artekin and Artekin (T) were applied to 100 patients with uncomplicated falciparum malaria, who were randomly divided into two groups. Each group contained 50 cases. The cure rate, the mean parasites clearance time, the mean fever clearance and side-effects were observed to assess the safety and efficacy of the compounds used. Results: The mean parasites clearance time was 31. 7±9.0 hours in the Artekin group and 32. 8±8. 8 hours in Artekin (T) group respectively; the mean fever clearance time was 12. 7±7. 2 hours in Artekin group and 16. 5±7. 9 hours in Artekin (T) group; there were no recrudescence case in both groups within the 28 days of follow-up, the cure rates in Artekin group and Artekin (T) groups were 100%. It indicated that the tolerability of both compounds were very good, the 相似文献
103.
粉被虫草提取物对巨噬细胞吞噬功能及CTL活性的影响 总被引:2,自引:0,他引:2
研究粉被虫草菌丝体提取物在体外对小鼠腹腔巨噬细胞吞噬功能和脾细胞免疫功能的影响,结果表明:粉被虫草提取物在正常情况下不仅能够促进小鼠腹腔巨噬细胞的吞噬功能,而在免疫抑制的情况下,一定浓度的粉被虫草菌丝体提取物还能恢复提高吞噬功能;它不仅能促进正常脾活化T细胞的增殖,而且能恢复环磷酰胺和氢化可的松抑制免疫小鼠脾活化T细胞的增殖;在较高浓度下能增高小鼠脾细胞毒T淋巴细胞(CTL)活性,同时在一定浓度下能恢复免疫抑制小鼠脾CTL活性。 相似文献
104.
本文收集了我省十年(1974—1983)来诊断为恶性淋巴瘤的病例,按免疫功能分类复查了全部切片,最后确诊为非何杰金氏恶性淋巴瘤(NHL)528例,进行了分析。本组NHL在首发部位、类型分布等方面与国内外有所不同。本组NHL首发于淋巴结外的占64.02%,明显高于国内其它省、市,而滤泡型淋巴瘤则低于国内多数地区。T细胞淋巴瘤占14.84%,较国内、外均低。并提出提高制片质量和广泛开展及应用免疫学技术的重要性。 相似文献
105.
T cell responses to orbital antigens in thyroid-associated ophthalmopathy. 总被引:3,自引:1,他引:2 下载免费PDF全文
K Arnold N Tandon R S McIntosh R Elisei M Ludgate A P Weetman 《Clinical and experimental immunology》1994,96(2):329-334
Thyroid-associated ophthalmopathy (TAO) is most likely to be a T cell-mediated disease, in which cytokines released in the extraocular muscles activate fibroblasts, increasing glycosaminoglycan production. The nature of the orbital antigen recognized by the infiltrating T cells is unclear, although it is possible that there is cross-reactivity between this and a thyroid autoantigen to explain the close association with thyroid autoimmunity. We have tested the ability of human and porcine eye muscle antigen preparations to stimulate proliferation of circulating T cells from healthy subjects and patients with TAO or Graves' disease without clinical TAO. Occasional responses were seen, particularly after depletion of CD8+ T cells, and two out of 10 TAO patients responded to eye muscle proteins of 25-50 kD after fractionation of antigens on gels and subsequent elution. There was no disease-specific response of T cells to R1, R14, D1 and 1D3, recombinant proteins identified from screening an eye muscle cDNA library with sera from patients with autoimmune thyroid disease. We have also found that interferon-gamma (IFN-gamma) production by T cells from TAO patients was not stimulated by eye muscle membrane antigens or by 1D3. These results suggest that the frequency of circulating T cells responding to eye muscle antigens in TAO is low, and that several candidate orbital antigens, including the 64-kD protein 1D3, are unlikely to be important T cell autoantigens in this condition. 相似文献
106.
A case of sclerosing epithelioid fibrosarcoma and its appearance on MRI is presented. The tumor showed a zonal architecture
on MRI with a large central core of very low signal intensity and a peripheral rim of intermediate to high signal intensity
on T1- and T2-weighted spin echo pulse sequences. The core showed decreased cellularity with dense collagen deposition on
histologic examination, and the peripheral zone increased cellularity with increased nuclear atypia. The presence of a prominent
region of very low signal intensity on T1- and T2-weighted images can be seen with neural tumors, giant cell tumor of the
tendon sheath, aggressive fibromatosis, and, in rare instances, with soft tissue sarcomas rich in collagen. 相似文献
107.
急性心肌梗死静脉溶栓后cTnT浓度比值对判断冠脉再通的价值 总被引:1,自引:0,他引:1
目的 探讨血清心肌肌钙蛋白T(cTnT) 3h 2h的浓度比值对急性心肌梗死 (AMI)溶栓后判定冠状动脉再通的价值。方法 采用ELISA法动态检测了 5 7例接受尿激酶静脉溶栓治疗的AMI患者和 31例正常健康对照血清cTnT ,CK MB及CK水平 ,并计算溶栓后 3h与 2h血清cTnT浓度比值。结果 ①cTnT释放呈现两种特征 ,再通组呈双峰型 ,未通组呈单峰型 ,且再通组后期峰值较未通组峰值低 (P <0 .0 1)。②cTnT浓度 3h 2h比值再通组明显高于未通组 (P <0 .0 1) ,以该比值 >1.4 8作为判定再通的标准 ,其对判定冠状动脉再通的敏感性、特异性、预测值分别为 83.3% ,90 .5 % ,93.8%。与峰值时间判定冠脉再通比较差异无显著性 (P >0 .0 5 )。结论 cTnT的动态检测可有效地判定对AMI溶栓后再通与否 ,特别是溶栓后 3h 2h浓度比值 >1.4 8可作为早期判定冠脉再通的标准 ,且具有迅速、省时等优点 ,值得推广应用 相似文献
108.
109.
Richard W. Bowtell Andrew Peters Jonathan C. Sharp Peter Mansfield Edward W. Hsu Nanci Aiken Anthony Horsman Stephen J. Blackband 《Magnetic resonance in medicine》1995,33(6):790-794
NMR microimages of single neural cells were acquired at 500 MHz using a conventional spin echo pulse sequence and a line-narrowing sequence that eliminates susceptibility effects. The data show that any contribution to the measured T2 relaxation rate arising from diffusion in local field inhomogeneities using spin echo sequences at high fields and high spatial resolution is relatively small. We conclude that the measured T2 difference between the nucleus and cytoplasm in these cells represents primarily a true T2 relaxation effect arising from the interactions of water with macromolecules in the two compartments and does not result from microsusceptibility differences. These observations have implications regarding water compartmentation in single cells and the interpretation of the MR characteristics of tissues in vivo. 相似文献
110.
T2毒素在灌流大鼠肠肝中的首过效应和代谢动力学 总被引:3,自引:0,他引:3
建立并用大鼠在体肠-肝灌流标本研究了T2毒素在大鼠肠肝中的首过效应和代谢转化动力学,T2毒素在大鼠肠肝中的主要代谢产物是HT2,3′-OHHT2和其葡萄糖醛酸结合物,T2毒素具有显著的肠肝首过效应,当毒素(42μg·ml~(-1))由上肠系膜动脉恒速单次灌流(8 ml·min~(-1))肠-肝标本时,穗态肝、肠抽提率分别为0.978和0.454,总有效清除率为7.91 ml·min~(-1),T2毒素在循环灌流大鼠肠-肝标本中的消除半衰期为6.5min,主要代谢产物HT2,3′-OHHT2的生成半衰期分别为8.5和38.5 min,结果表明,T2毒素经消化道中毒后,在肠和肝的首过代谢下能很快地转化为产物,因此,毒素在体内的毒效作用主要由其代谢产物表现出来。 相似文献