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21.
A synthetic 10-kD heat shock protein (hsp10) from Mycobacterium tuberculosis modulates adjuvant arthritis 下载免费PDF全文
S. RAGNO V. R. WINROW P. MASCAGNI P. LUCIETTO F DI PIERRO C. J. MORRIS D. R. BLAKE 《Clinical and experimental immunology》1996,103(3):384-390
The heat shock protein, hsp10, is an abundant protein in Mycobacterium tuberculosis (Mtb), its nucleotide sequence encoding a protein of 99 amino acids with a molecular mass of 10±7kD. This sequence is phylogenetically conserved, being represented by the GroES homologue of Escherichia coli. Hsp 10 and GroES are members of the chaperonin 10 family of molecular chaperones, and GroES is necessary for the optimal activity of GroEL, a member of the chaperonin 60 family and the E coli homologue of mycobacterial hsp65. Since hsp65 has been implicated in both experimental and human rheumatoid arthritis, we aimed to assess the immunomodulatory effects of its co-chaperonin, hsp10, in experimental arthritis. Our results show that an aqueous solution of a mycobacterial hsp10 delayed the onset and severity of adjuvant-induced arthritis in rodents when administered after disease induction but before joint involvement occurred. This biological activity was specific for the hsp10 of Mtb, since neither GroES nor the rat homologue was effective. Using synthetic hsp10 fragments, the activity was localized to the N-terminal region of the molecule. Assessment of circulating antibody levels to mycobacterial hsp10 and hsp65 indicated that all arthritic rats had increased litres to both hsp10 and hsp65: hsp10-treated rats showed further elevation of this humoral response not only to hsp10 but also to hsp65 when compared with the untreated arthritic control. This is the first report of the immunomodulatory activity of mycobacterial hsp10 in experimental arthritis, and exhibits a potential role for this co-chaperonin in pathophysiological situations. 相似文献
22.
糖尿病大鼠心肌NF-κB、iNOS、COX-2表达的研究 总被引:2,自引:3,他引:2
目的:观察核因子-κB(NF-κB)、诱导型一氧化氮合酶(iNOS)以及环氧化酶-2(COX-2)3种炎症因子在糖尿病大鼠心肌组织的表达。方法:30只SD大鼠随机分为正常对照组和糖尿病组,糖尿病组大鼠按60 mg/kg的剂量1次性腹腔注射链脲菌素。实验于24周末结束,观察2组大鼠的体重、平均血糖浓度、心重指数。并取心肌组织石蜡切片分别行NF-κB、iNOS和COX-2免疫组化染色。同时用凝胶电泳迁移率(EMSA)的方法测定心肌组织NF-κB活性。结果:(1)糖尿病大鼠心肌组织NF-κB阳性表达细胞明显多于对照组;(2)EMSA方法显示,糖尿病大鼠心肌组织NF-κB表达强度明显高于对照组;(3)对照组大鼠心肌组织未见iNOS的表达,糖尿病大鼠见明显iNOS的表达;(4)对照组大鼠心肌组织偶见COX-2的表达,糖尿病大鼠见明显COX-2的表达。结论:NF-κB、iNOS和COX-2在糖尿病大鼠心肌组织中表达活性明显增强。 相似文献
23.
C基因截短的HBV复制与包装 总被引:1,自引:0,他引:1
目的 探讨C基因截短型HBV变异体的复制与包装。方法 采用分子克隆、人工定点突变等技术构建C基因截短型HBV变异体质粒,用脂质体法转染HepG2细胞,提取细胞内及培养上清液中DNA分别进行Southem杂交,PCR及实时定量荧光PCR分析。结果 经DNA测序及酶切鉴定证实C基因截短型HBV质粒载体构建成功;C基因截短型HBV为复制缺损型,与辅助质粒共转染HepG2细胞,可在细胞内及培养上清液中检测到HBV各种DNA构型;DNA定量分析提示C基因截短型HBV的包装效率较野生型HBV提高3~40倍。结论 C基因截短型HBV变异体为复制缺损型,单独转染后不能在肝细胞内包装与复制,但在缺失包装信号ε的相应辅助病毒辅助下可有效复制并包装成子代病毒颗粒分泌到胞外,且包装效率大大提高。 相似文献
24.
25.
S. E. RICKSTEN T. YAO G. F. DI BONA P. THORN 《Acta physiologica (Oxford, England)》1981,112(2):161-167
Exaggerated natriuresis upon volume loading occurs in both human and animal hypertension and is mainly due to suppressed tubular reabsorption. To explore whether altered renal sympathetic activity contributes to this response, conscious male spontaneously hypertensive rats (SHR) were exposed to isotonic saline loading in comparison with normotensive male Wistar Kyoto rats (WKR). After a 60 min control hydropenic period, during which mean arterial pressure, heart rate, renal sympathetic nerve activity and urinary sodium excretion were followed, a 60 min period of intravenous volume expansion with isotonic saline (0.2 ml/minx 100 g b. w.) was started followed by a 60 min hydropenic recovery period. Already during the control period sodium excretion was significantly higher in SHR. During the volume load and subsequent recovery period a clearly exaggerated natriuresis occurred in SHR compared with WKR. Further, volume loading reduced renal sympathetic nerve activity in all animals, but significantly more in SHR. Moreover, volume loading reduced mean arterial pressure and heart rate in both groups. It is suggested that the accentuated reflex inhibition of renal sympathetic activity in SHR upon volume loading emanates from cardiac mechanoreceptors and partly explains the exaggerated natriuresis in SHR. This augmented ‘volume’ reflex response is probably due to reduced systemic venous compliance in SHR with a consequently increased central filling and cardiac receptor activation. 相似文献
26.
目的制作兔肝纤维化模型,观察血管活性物质与门静脉压力变化的关系。方法40只家兔采用口服硫代乙酰胺方法造模,分别于造模第8、12、16、20周时检测内皮素(ET-1)及NO浓度,超声观察胆囊壁及肝脏血流动力学指标,直接穿刺测量不同时期门静脉压力。分析血管活性物质与肝脏血流动力学指标及门静脉压力变化间的关系。结果胆囊壁增厚是肝纤维化阶段的二维超声表现;随着纤维化程度的加重,血清ET-1、NO浓度逐渐增加,且以ET-1/N0比值增加更为明显;门静脉内压力、肠系膜上动脉、脾动脉搏动指数(PI)随纤维化程度逐渐增加,实验组与对照组间差异有统计学意义(P〈0.05),且与ET-1/NO值呈正相关(P〈0.01)。结论通过超声可无创检测肝脏血流动力学变化,对肝纤维化临床诊断及治疗效果的观察,具有积极的作用。 相似文献
27.
目的:研究碘化钾、碘酸钾对大鼠甲状腺形态学结构的影响。方法:将Wistar大鼠随机分为4组,低碘组(LI)、正常组(NI)、碘化钾组(KI)、碘酸钾组(KIO3),3个月后观察形态学变化,并做体视学分析,获得定量参数后进行统计学处理。结果:LI组滤泡及滤泡腔的平均体积VQ、平均表面积SQ、体积密度VV、表面积密度SV均明显小于NI组,而数密度NV及比表面积S/V均明显高于NI组;经治疗3个月后,KI组和KIO3组的上述指标均有明显恢复,但尚未完全恢复正常。KI组和KIO3组之间无显著性差异。结论:低碘可致大鼠甲状腺形态典型的小滤泡增生性改变,而KI和KIO3在治疗缺碘性甲状腺肿方面均有很好的疗效,且在本实验期间两者的疗效无显著性差异。 相似文献
28.
目的:建立湿热内蕴证候大鼠模型,研究具有降血尿酸作用的清利湿热方的中医功效,以证测效揭示清利湿热降血尿酸作用机制。方法:将48只SD大鼠随机分为空白组、模型组、四妙丸组以及清利湿热方低、中、高剂量组,每组8只。采用饲喂高脂高糖饲料,自由饮用蜂蜜水,并隔天灌胃猪油脂或酒,建立湿热内蕴证候大鼠模型,观察清利湿热方对大鼠一般状态的影响。采用酶联免疫吸附试验检测血清热激蛋白70(HSP70)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β),促胃液素(GAS)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)含量以及血浆胃动素(MTL)、肝脏组织Na+-K+-ATP酶含量,免疫组织化学法检测胃肠组织水孔蛋白3(AQP3)、水孔蛋白4(AQP4)含量,采用蛋白质印迹法检测结肠组织中TOLL样受体4(TLR4)、核因子κBp65表达量。结果:模型组体质量下降(P<0.05,P<0.01),HSP70、TNF-α、IL-1β升高(P<0.05,P<0.01,P<0.001),胃肠组织中AQP3表达量下降(P<0.05),AQP4表达量上升(P<0.01,P<0.001),GAS含量下降(P<0.01),IgM含量升高(P<0.01),结肠组织TLR4表达量增加(P<0.01)。清利湿热方能增加大鼠体质量,降低HSP70、TNF-α、IL-1β含量(P<0.05,P<0.01,P<0.001),升高胃肠组织AQP3表达量(P<0.05,P<0.01,P<0.001),降低AQP4表达量(P<0.05),升高GAS、Na+-K+-ATP酶含量(P<0.05,P<0.001),降低IgM含量(P<0.05,P<0.01)。结论:饲喂高脂高糖饲料,自由饮用蜂蜜水,并隔天灌胃油脂/酒,可以成功建立高尿酸血症湿热内蕴证候模型,清利湿热方可以从大鼠一般状态、体质量、热激蛋白以及炎症介质、水孔蛋白、胃肠激素、免疫等多方面改善大鼠湿热状态,发挥清利湿热功效。清利湿热方具有降血尿酸作用,其作用机制可能与下调TLR4,核因子κBp65有关。 相似文献
29.
目的 探讨尘肺合并肺结核的发病特点。方法 对历年来职业病档案中的现患及死亡病例逐个核实统计。结果 ①单纯尘肺560例,尘肺合并肺结核156例,合并率为21.79%。②退伍工程兵合并结核病死亡率高于厂矿企业工人。③尘肺合并肺结核死亡高于其他疾病。结论 ①尘肺合并肺结核率随期别的增加而显著增高;②尘肺合并肺结核发病率随年代的增加而降低;③尘肺合并肺结核死亡率高于单纯尘肺死亡率,随尘肺期别的增加而增高;④尘肺合并肺结核死亡所占比例随年代的增加而显著降低。 相似文献
30.
Exogenous insulin-like growth factor II enhances post-infarction regional myocardial function in swine 总被引:1,自引:0,他引:1
BATTLER A.; HASDAI D.; GOLDBERG I.; OHAD D.; DI SEGNI E.; BOR A.; VARDA-BLOOM N.; VERED Z.; KORNOWSKI R.; LAKE M.; NASS D.; SAVION N. 《European heart journal》1995,16(12):1851-1859
OBJECTIVES: Insulin-like growth factor II (IGF-II) promotes cardiac myocytegrowth and contractility in vitro. This study was designed toinvestigate the effect of exogenous IGF-II on regional myocardialfun ction at the area of infarct in the pig. METHODS: Myocardial infarction was induced in 12 female anoesthetizedpigs by affigel blue beads, embolizing microvessels of the leftanterior descending coronary artery distribution. In the experimentalgroup (n=6), IGF-II (0.12 µg. kg1 in two animalsand 0.6 µg. kg1 in four) was incorporated intothe beads and delivered by them to the infarct area. Myocardialfunction was followed echocardiographically, and the excisedheart was analysed immunohistochemically and histopathologically. RESULTS: Myocardial function in injured zones, inversely related to anechocardiographic segmental wall motion score (mean ±SEM), was similar between the two groups at baseline, but at4 weeks post-infarction was significantly (P=0.008) reducedin the control group (0.58± 0.38 vs 3.42 ± 0.84),in contrast to nearly baseline values in the experimental group(0.58 ± 0.33 vs 1.17 ± 0.42, P=0.41). Cardiacperformance in injured segments was sign better after myocardialinjury in the experimental group (P=0.04). Tissue samples fromboth groups (4 weeks post-infarction), stained with haematoxylinand eosin demonstrated pen-infarct myocyte hypertrophy, correspondingto regions selectively stained by an antibody for CD56, whichhighlights growing cardiac myocytes. By image analysis semi-quantification,staining for CD56 was significantly (P=0.04) higher in the peri-infarctregion of the experimental group, as compared with controls(106.5 ± 2.8 vs 92 ± 4.4 gray level units). Microvesselsstained for von-Willebrand factor were similar in nwnber inboth groups (P=0.8), as were mesenchymal cells stained for vimentin(P=0.7). CONCLUSIONS: Exogenous IGF-II, delivered to the infarct area amelioratesregional cardiac function in the pig, perhaps by inducing peri-infarctmyocyte growth. 相似文献