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61.
BACKGROUND: We have previously demonstrated that the proteolytic activity of Der p 1 selectively cleaves human CD25, the 55 kDa alpha subunit of the IL-2 receptor. As a result of cleavage of surface CD25, peripheral blood T cells produce less IFN-gamma and more IL-4, thereby leading to progressive polarization of the T cells towards a Th2 cytokine profile. Therefore, these observations underline the potential role of the proteolytic activity of Der p 1 in creating a microenvironment conducive for IgE synthesis. OBJECTIVE: To study the effect of T cells that have been conditioned by the proteolytic activity of Der p 1 on IgE synthesis by B cells. METHODS: We have examined this concept in experiments whereby T cells that have been exposed to either proteolytically active or inactive Der p 1 were cocultured with autologous B cells and IgE antibody synthesis was monitored. RESULTS: Here we demonstrate for the first time that coculturing T cells that have been in contact with proteolytically active Der p 1 with autologous B cells leads to augmentation of IgE antibody responses. CONCLUSIONS: The proteolytic activity of Der p 1 conditions human T cells, which then become empowered to trigger enhanced IgE synthesis by B cells. 相似文献
62.
63.
Hiroyoshi Suzuki Taisuke Otsuki Yuzo Iwasaki Ryuichi Katakura Hideshi Asano Mamoru Tadokoro Yoichi Suzuki Fumiaki Tezuka Hidehiro Takei 《Neuropathology》2002,22(1):40-47
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10). 相似文献
64.
目的 :研究cyclinD1 bcl 1和p2 7 kip1在脑胶质瘤中表达及其与病理分级和患者预后的关系。方法 :用免疫法组化技术对 4 8例不同恶性程度 (WHO分类法 )的脑胶质瘤组织和 12例非肿瘤组织中cyclinD1 bc1 1和p2 7 kip1蛋白的表达作了检测 ,用图像分析系统定量分析 ,并与临床资料紧密相联系进行统计学处理。结果 :两种蛋白的免疫反应复合物定位于细胞核。其在脑胶质瘤中的阳性表达都高于非肿瘤组织 (P <0 0 5 ) ,cyclinD1 bcl 1阳性颜色的数量和强度都随肿瘤的恶性程度升高而增加 (P <0 0 5 ) ,相反p2 7 kip1阳性染色的数量和强度都随肿瘤的恶性程度升高而降低 (P <0 0 5 )。cyclinD1 bcl 1的高表达或 和p2 7 kip1的低表达预示着预后差。结论 :CyclinD1 bcl 1和p2 7 kip1的异常表达可能与脑胶质瘤的发生发展密切相关 ,二者可能有协同作用。二者的表达都可作为判断预后的一个指标 相似文献
65.
p38丝裂原活化蛋白激酶在糖尿病大鼠神经病理性痛中的作用 总被引:1,自引:0,他引:1
目的探讨p38丝裂原活化蛋白激酶(p38MAPK)在链脲菌素诱导的糖尿病大鼠神经病理性痛中的作用。方法雌性Wistar大鼠31只,3月龄,体重180~220g,随机分为3组:对照组(C组,n=10)、糖尿病神经病理性痛组(D组,n=11)和p38MAPK抑制剂组(Ⅰ组,n=10)。D组、Ⅰ组单次腹腔注射链脲菌素65mg/kg制备糖尿病模型。糖尿病模型制备成功后,Ⅰ组尾静脉注射p38MAPK抑制剂SB203580 0.5mg/kg,1次/周,连续4周;C组和D组尾静脉注射等体积的生理盐水。给药4周后,测定机械缩足反应阈值(MWT)、左侧坐骨神经传导速率(NCV)、背根神经节(DRG)和脊髓的磷酸化p38MAPK水平。结果与C组比较,D组、Ⅰ组MWT下降,NCV减慢,伴有脱髓鞘现象,DRG和脊髓的磷酸化p38MAPK水平升高;与D组比较,Ⅰ组MWT升高,NCV增快,脱髓鞘程度减轻,DRG和脊髓的磷酸化p38MAPK水平下降。结论p38MAPK信号转导通路参与了糖尿病大鼠神经病理性痛的形成。 相似文献
66.
Background Gene therapy by adenovirus-mediated wild-type p53 gene transfer has been shown to inhibit lung cancer growth in vitro, in animal models, and in human clinical trials. The antitumor effect of selective cyclooxygenase (COX)-2 inhibitors has been demonstrated in preclinical studies. However, no information is available on the effects of p53 gene therapy combined with selective COX-2 inhibitor on COX-2 gene expression and growth inhibition of human lung cancer cells. Methods We evaluated the effects of recombinant adenovirus-p53 (Adp53) gene therapy combined with selective CADX-2 inhibitor on the proliferation, apoptosis, cell cycle arrest of human lung adenocarcinoma A549 cell line, and the effects of tumor suppressor exogenous wild type p53 on COX-2 gene expression. Results Ad-p53 gene therapy combined with selective COX-2 inhibitor celecoxib shows significant synergistic inhibition effects on the growth of human lung adenocarcinoma A549 cell line. Exogenous p53 gene can suppress COX-2 gene expression. Conclusions Significant synergistic inhibition effects of A549 cell line by the combined Ad-p53 and selective COX-2 inhibitor celecoxib may be achieved by enhancement of growth inhibition, apoptosis induction and suppression of COX-2 gene expression. This study provides first evidence that the administration of p53 gene therapy in combination with COX-2 inhibitors might be a new clinical strategy for the treatment or prevention of NSCLC. 相似文献
67.
Molecular staging of head and neck squamous carcinoma 总被引:3,自引:0,他引:3
The staging system of head and neck cancer is a Tumor-Node-Metastases system that was developed by the American Joint Committee on Cancer. The stage of the head and neck cancer defines the extent of the lesion and is determined by physical examination, radiologic studies, and pathologic examination. Accurate staging of head and neck cancer is critical since it will determine the treatment modalities used to cure the disease. Recent advances in the field of molecular genetics have allowed clinicians to detect occult cancer cells previously missed by physical examination and standard histopathologic techniques. Molecular assays are 500 times more sensitive in identifying cancer cells than standard techniques and provide more objective analyses with fewer sampling errors. Consequently, these techniques are currently being used to perform molecular staging of head and neck cancer patients. Preliminary results show that molecular staging will accurately identify those patients at significantly increased risk for recurrence of their head and neck cancer. 相似文献
68.
Anthonie J. van Essen Coen J. F. Schoots Richard A. van Lingen Marian J. E. Mourits Joep H. A. M. Tuerlings Bieke Leegte 《American journal of medical genetics. Part A》1993,47(1):85-88
We report on the clinical and pathologic findings in a girl with isochromosome 18q (46, XX,i(18q)) who had combined manifestations of monosomy 18p and trisomy 18q. Major congenital anomalies included premaxillary agenesis, alobar holoprosenphaly, double Outlet right ventricle, DiGeorge anomaly and streak ovaries. The clinical spectrum in i(18q) is very broad. © 1993 Wiley-Liss, Inc. 相似文献
69.
Rawatmal B. Surana Syed K. Rafi Kevi L. Christopher Thomas J. Reid Raymond B. Weiss 《Clinical genetics》1995,47(6):321-323
An apparently balanced de novo reciprocal translocation t(5;21) (q13;q22) was demonstrated in a girl with acrobrachycephaly, ventriculomegaly, pulmonary stenosis and anal malformation. The possible relationships between her karyotype and malformations are discussed. 相似文献
70.
应用抗增殖细胞核抗原和抑癌基因p53蛋白的单克隆抗体对37例放疗或化疗后的肺癌进行了检测,并与未经术前治疗的肺癌组织进行对照,部分组织进行了超微结构观察。结果发现:(1)放疗或化疗对肺癌组织细胞浆及胞核有不同程度的破坏。(2)放、化疗后组织(除分化型腺癌外)PCNA指数下降明显(P<0.01或P<0.05)。(3)放疗后肺癌组织p53表达率减低,但化疗后变化不明显。 相似文献