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41.
Wang L Zhu YF Guo XJ Huo R Ma X Lin M Zhou ZM Sha JH 《Journal of molecular medicine (Berlin, Germany)》2005,83(10):812-821
The ovary plays a central role in oogenesis and gonadal hormone secretion. Proteomic analysis is a valuable approach for gaining an increased understanding of the molecular nature of the ovary. In this work, two-dimensional electrophoresis for protein separation followed by matrix-assisted laser desorption/ionization mass spectrometry and database searches, identified 231 protein spots corresponding to 138 individual proteins that were found in gels representing both the follicular and luteal phases. The data were used to construct a database online (). The identified proteins were functionally classified into seven groups: (1) cell signaling/communication, (2) cell division, (3) gene/protein expression, (4) metabolism, (5) cell structure and motility, (6) cell/organism defense, and (7) unclassified. Among the proteins identified, 47% had not been previously reported in the human ovary. In addition, a number of disease-related proteins were identified in this protein map, including some cancer- and polycystic ovarian syndrome-related proteins. Two proteins with phosphorylation were verified by Western blot analysis. Comparison of protein abundance between follicular and luteal stages produced seven protein spots that had been identified in our database. This study provides a preliminary reference map of normal human ovary that will form a basis for comparative studies on normal and pathological conditions of the human ovary and may serve as a potential tool for clinical diagnosis, therapeutics, and prognosis.Electronic Supplementary Material Supplementary material is available in the online version of this article at L. Wang and Y.-F. Zhu contributed equally to this work 相似文献
42.
I.P. Witz Margalit Yaakubowicz Ilana Gelernter Y. Hochberg Romema Anavi Maya Ran 《Immunobiology》1984,166(2):131-145
Serum from young normal BALB/c mice was found to contain IgM antibodies able tomediate complement-dependent lysis of certain syngeneic or allogeneic tumor target cells. The titer of such naturally occurring antitumor antibodies (NATA) was found to increase with aging.A longitudinal serological study comparing the cytotoxicity potential of NATA fromnormal and from urethan-treated BALB/c mice was performed. It was found that urethan-treated mice that did not develop primary lung-adenomas within the duration of the experi-ment had significantly lower NATA titers, against one out of 4 target cells assayed, than urethan-treated animals that developed lung adenomas. This difference was evident in two independent experiments. The results suggested that the lower NATA activity of the urethan-treated mice that did not develop tumors existed even before exposure to the carcinogenic insult. This raises the possibility that certain populations could be segregated according to their natural antibody profile into those individuals which will develop primary tumors within a certain period if exposed to a subthreshold amount of carcinogen, and those which will not. 相似文献
43.
Takasaki Y Kaneda K Matsushita M Yamada H Nawata M Matsudaira R Asano M Mineki R Shindo N Hashimoto H 《International immunology》2004,16(9):1295-1304
Using 2-dimensional electrophoresis and ion-pair chromatography, we have identified elements of proliferating cell nuclear antigen (PCNA) multiprotein complexes that are reactive to antibodies in sera from patients with systemic lupus erythematosus. Among the various elements of the complexes, a 37 kDa protein (PI 8.5) that specifically reacted with SLE sera, but not with sera from patients with other connective tissue diseases, was identified as glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Immunoblot analysis showed that SLE sera reactive with the 37 kDa protein specifically reacted with GAPDH, as did anti-GAPDH mAbs. The purified autoantibodies to GAPDH from lupus serum showed both nuclear speckled and cytoplasmic staining patterns in immunofluorescence on Hep-2 cells. In addition, enzyme-linked immunosorbent assay (ELISA) revealed the presence of anti-GAPDH autoantibodies in 47% of lupus patients. Longitudinal analysis of the reactivity of lupus sera to PCNA complexes showed the autoimmune response to spread from GAPDH to other elements of PCNA complexes, and the presence of anti-GAPDH antibodies was significantly correlated with increased levels of serum PCNA. Taken together, these findings suggest that GAPDH interacting with PCNA in association with its cellular function is a novel autoantigen recognized by lupus sera, and that GAPDH thus plays an important role in the induction of autoimmune responses against the PCNA complex. 相似文献
44.
首次选用双相成核剂CaF2 和TiO2 为制备遮色瓷的成核剂 ,以SiO2 —Al2 O3 —K2 O—Na2 O系统为其基质成分 ,采用差热分析仪、扫描电镜和x衍射分析仪等实验手段来探讨本体系遮色瓷制备的热处理制度。结果表明阶梯制度的热处理方式适用于本体系的遮色瓷。瓷粉经过如下的热处理制度 :从室温以 8℃ /min的加热速度升温至 75 0℃保温 1h ,然后再以4℃ /min的升温速度升至 96 0℃ ,保温 2h后冷淬 ,其白榴石晶体的析晶行为良好 ,且晶体尺寸较小 (约 1μm左右 )。该热处理制度的确定为改善遮色瓷与金属的热匹配性和提高遮色瓷的理化性能提供了基础 相似文献
45.
Fibroblast growth factor 2 induces differentiation and apoptosis of Askin tumour cells 总被引:7,自引:0,他引:7
Kim MS Kim CJ Jung HS Seo MR Juhnn YS Shin HY Ahn HS Thiele CJ Chi JG 《The Journal of pathology》2004,202(1):103-112
Peripheral primitive neuroectodermal tumour (PNET)/Ewing's sarcoma (ES) and neuroblastoma (NB) are related tumours of neural crest origin with primitive neural characteristics. Fibroblast growth factor 2 (FGF2) is a critical signalling molecule for primitive neural crest cells. The treatment of NB cells with FGF2 variably affects biological characteristics such as growth and differentiation, while in PNET/ES, FGF2 predominantly induces apoptosis. The JK-GMS Askin tumour cell line can be induced to differentiate upon treatment with nerve growth factor (NGF), indicating the integrity of the cellular machinery necessary for differentiation. The present study assesses whether FGF2 can induce differentiation in JK-GMS cells. JK-GMS cells expressed high-affinity FGF receptors (FGFRs), and treatment with FGF2 induced phosphorylation of FGFR1 together with activation of extracellular signal-regulated kinases (ERK1/ERK2) and c-Jun N-terminal kinase (JNK). Subsequent biological effects were growth inhibition, neuronal differentiation, and apoptosis, and these changes were associated with increased expression of neurofilaments, reduction of c-myc and bcl-2 expression, and activation of caspase 3. Treatment of the cells with a specific inhibitor of the MAPK/extracellular signal-regulated kinase (MEK)-1, PD98059, predominantly inhibited the effects of FGF2 on growth, differentiation, and apoptosis, while an inhibitor of JNK reduced apoptosis, indicating that the ERK1/2 and JNK pathways are critical components of FGF2-mediated effects in JK-GMS cells. Additional comparative analyses of FGF2-mediated effects in two ES cell lines (CADO-ES, RD-ES) and a PNET cell line (SK-N-MC) showed pronounced differentiation in SK-N-MC, but not in CADO-ES or RD-ES cells. This study demonstrates that FGF2 can induce neuronal differentiation of PNET including Askin tumour. These findings clearly indicate that the FGF2-mediated signalling pathway plays a critical role in controlling the major properties of PNET cells and may provide a potential therapeutic target for PNET. 相似文献
46.
目的:建立一套合理而便捷的实验体系,为开发新型免疫调节性寡聚脱氧核苷酸(ODN)提供筛选方法。方法:利用含有CpG基序的免疫刺激性寡聚脱氧核苷酸(CpG ODN)作为刺激物,将人外周血单个核细胞(PBMC)作为研究对象,分别以细胞的增殖程度和刺激上清的抗病毒活性作为检测指标,优化各项实验条件,综合评定寡聚脱氧核苷酸的免疫调节活性。结果:成功建立了由阳性免疫调节性ODNA151抑制CpG ODN诱导的人PBMC增殖及抗病毒活性的筛选方法。结论:免疫调节性ODN筛选方法的成功建立,为下一步研究开发新型免疫调节性ODN奠定了基础。 相似文献
47.
通过对母料载体树脂的筛选,无机填料的选择,添加性能优良的耐辐射助剂,制成了具有耐辐射性能、加工性能良好的母料,该母料的制备工艺简单。本文所述的填充级HDPE专用料是将HDPE与填充母料经过简单掺混制成的。经测试专用料满足国家医药标准YY 0114—93《医用输液、输血、注射器聚乙烯专用料》的要求。制品厂试验表明:该填充级的HDPE专用料加工性能良好,用该填充级HDPE专用料注射成型的注射器芯杆装配成一次性注射器满足国家专业标准ZBC 31009—87《一次性无菌注射器》的要求。该填充母料的加入可大大降低材料的成本,100份HDPE 7006A可添加67份填充母料,该填充级专用料的价格比HDPE树脂降低约1500元/吨,因此该填充级HDPE专用料的推广和使用具有良好的经济效益。 相似文献
48.
This study was performed to investigate the effects of behavior modification on body image, depression and body fat in obese elementary school children. Sixty-two elementary students of the 4th to 6th grade were selected from two different Seoul schools. Thirty-four children in one school were designated as the experimental group, and 28 children from the other school as the control group. The experimental group received 60 - 70 minutes of behavior modification, once a week, for 8 weeks. The control group received neither management nor treatment. The results indicated a significant improvement of body image and a reduction in the increase rate of body fat for the experimental group. This finding strongly supports the theory that behavior modification can be used as an effective strategy in the treatment of obese children. 相似文献
49.
为了探讨趋化性细胞因子在体外对人Tc1和Tc2亚群细胞内Ca2 + 浓度变化的影响 ,从PBMC中分离纯化CD8+ T细胞 ,在特定细胞因子及细胞因子抗体作用下 ,体外定向诱导出能长期培养的Tc1和Tc2细胞系 ,用免疫荧光染色结合流式细胞术分析对其进行鉴定后 ,通过流式细胞术检测在趋化性细胞因子刺激前后 ,细胞内Ca2 + 浓度的变化。发现受SDF 1作用后 ,Tc1及Tc2细胞内Ca2 + 浓度变化均不明显 ,而IP 10刺激后 ,Tc1及Tc2细胞内Ca2 + 水平在短时间内明显上调 ,且在Tc1胞内的上升幅度远高于Tc2细胞 ,在MIP 1β刺激后 ,也观察到类似趋势 ;受Eotaxin刺激后 ,Tc1及Tc2细胞内Ca2 + 水平均有微小上升 ,在Tc2细胞内的上升幅度略高于Tc1细胞。说明Tc1和Tc2细胞受趋化性细胞因子作用后 ,细胞内Ca2 + 浓度有不同程度的变化 ,且与趋化性细胞因子受体的表达呈现一定的相关性。 相似文献
50.
目的: 探讨单磷酸腺苷(AMP)激活的蛋白激酶(AMPK)对心肌肥厚的影响及可能涉及的作用机制。方法: 通过对大鼠行腹主动脉缩窄术(TAC)引起压力负荷增加,造成心肌肥厚的模型。术后24 h起经皮下注射AMPK的特异性激活剂AICAR(0.5 mg·kg-1·d-1)直至术后7周。处死动物前,对大鼠进行超声心动学指标的检测和血清游离脂肪酸浓度测定;处死动物,取心脏称重后计算心脏重/体重比值,测量心肌细胞的平均直径、心肌中的游离脂肪酸含量、过氧化体增殖物激活型受体α(PPARα)和肉碱棕榈酰转移酶(CPT-I)的mRNA表达。结果: (1)心肌肥厚+AICAR组大鼠的心脏重/体重比值、心肌细胞平均直径、血清及心肌中游离脂肪酸的浓度明显低于心肌肥厚对照组;(2)心肌肥厚+AICAR组大鼠心肌PPARα及CPT-I的mRNA表达明显高于心肌肥厚对照组;(3) 心肌肥厚+AICAR组大鼠心脏超声心动学指标:左室后壁舒张末期厚度、左室舒张、收缩末期内径 (PWT, LVDD, LVSD) 低于心肌肥厚对照组,左室短轴缩短率 (FS%) 则高于心肌肥厚对照组。结论: 活化的AMPK可能通过增强心肌脂肪酸氧化从而抑制压力负荷增加引起的心肌肥厚。 相似文献