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81.
目的:利用核因子κBp65特异性小干涉核糖核酸抑制肿瘤坏死因子α诱导的关节滑膜细胞中一氧化氮合酶2和环氧合酶2的表达,探讨基因治疗类风湿性关节炎的新方法。方法:实验于2005-03/2006-03在北京大学医学部中心实验室(国家级)完成。①实验材料:清洁级健康近交系SD大鼠10只;一氧化氮合酶2,环氧合酶2,3-磷酸甘油醛脱氢酶引物(由北京奥科生物公司合成);肿瘤坏死因子α(Sigma公司);核因子κBp65特异性小干涉核糖核酸和转染条件由北京大学运动医学研究所陈连旭博士提供。②实验干预:切取大鼠髋关节和膝关节的滑膜体外培养滑膜细胞。利用脂质体siPORTTMLipid将核因子κBp65特异性小干涉核糖核酸转染滑膜细胞,再加入肿瘤坏死因子α刺激。阴性对照为任意编码的小干涉核糖核酸,阳性对照为针对3-磷酸甘油醛脱氢酶的小干涉核糖核酸。③实验评估:提取滑膜细胞中的核蛋白,利用电泳迁移率试验检测核因子κB的活性;提取滑膜细胞的核糖核酸和总蛋白,利用反转录聚合酶链反应和蛋白质免疫印记法从信使核糖核酸和蛋白质两水平检测一氧化氮合酶2和环氧合酶2的表达。结果:①肿瘤坏死因子α和核因子κBp65特异性小干涉核糖核酸对核因子κB转录活性的影响:与正常滑膜细胞相比,肿瘤坏死因子α可以显著提高核因子κB的结合能力,而事先转染小干涉核糖核酸48h,再用肿瘤坏死因子α刺激,核因子κB的结合能力又显著降低。②核因子κBp65特异性小干涉核糖核酸对核因子κB下游因子的影响:在培养的滑膜细胞中,肿瘤坏死因子α可以显著增加一氧化氮合酶2和环氧合酶2的表达;在转染小干涉核糖核酸抑制核因子κBp65的表达后再用肿瘤坏死因子α刺激,一氧化氮合酶2和环氧合酶2的表达被抑制。结论:①核因子κBp65特异性小干涉核糖核酸可降低肿瘤坏死因子α诱导的滑膜细胞中核因子κB的转录活性,抑制其下游因子一氧化氮合酶2和环氧合酶2的表达。②核因子κBp65特异性小干涉核糖核酸可用于基因治疗类风湿性关节炎的试验研究。  相似文献   
82.
尼莫地平对烫伤大鼠脑内ZO-1 mRNA及血脑屏障通透性的影响   总被引:2,自引:0,他引:2  
目的:观察尼莫地平对严重烫伤大鼠脑内紧密连接相关蛋白ZO-1mRNA及血脑屏障通透性的影响。方法:实验于2005-04/10在南昌大学基础医学院应用解剖实验室完成。①取健康SD大鼠132只分为正常对照组12只、烫伤组60只,尼莫地平组60只,后两组又设烫伤后1,3,6,12,24h5个时间点,每个时间点12只,其中6只用于脑组织伊文思蓝含量的测定,剩余6只用于ZO-1mRNA的检测。②烫伤组和尼莫地平组大鼠100℃开水烫伤15s,造成背部30%体表总面积Ⅲ度烧伤。尼莫地平组大鼠于烫伤后即刻腹腔注射尼莫地平(0.5mg/kg),其他2组不给药。③各组大鼠于相应的时间点麻醉并处死动物取材,应用化学定量方法检测大鼠脑组织内伊文思蓝含量,运用RT-PCR方法检测大鼠脑内ZO-1mRNA的表达变化。结果:经补充后132只大鼠进入结果分析。①大脑伊文思蓝含量:正常对照组为(10.18±1.79)μg/g,烫伤组伤后1,3,6,12h均高于正常对照组(P<0.05),其高峰在烫伤后6h,为(20.00±0.58)μg/g;尼莫地平组伤后1,6,12h均低于烫伤组(P<0.01),烫伤后6h时为(16.74±0.78)μg/g。②小脑伊文思蓝含量:正常对照组为(12.90±1.32)μg/g,烫伤组伤后1,3,6,12h均高于正常对照组(P<0.05),其高峰在烫伤后6h,为(31.3±1.47)μg/g;尼莫地平组伤后1,3,6,12h均低于烫伤组(P<0.01),烫伤后6h时为(21.05±2.36)μg/g。③脑组织ZO-1mRNA的表达:烫伤组烫伤后3,6,12,24h分别为正常对照组的(0.1235±0.0158),(0.1890±0.0531),(0.2014±0.0412),(0.1555±0.0163)倍(P<0.01);尼莫地平组较烫伤组高,以烫伤后3,6h最为明显,分别为烫伤组的3.96及1.81倍(P<0.01).结论:①严重烫伤后血脑屏障通透性增高,脑内ZO-1mRNA表达下降。②烫伤后早期应用尼莫地平能防止脑内ZO-1mRNA表达下降,并能起到保护血脑屏障功能的作用。  相似文献   
83.
Medium conditioned by tumor necrosis factor alpha (TNF-alpha)-stimulated polymorphonuclear leukocytes (PMN) (CM-TNF) suppresses PMN migration. Therefore, we wished to identify the agent(s) in CM-TNF that mediated antichemotactic activity. CM-TNF was fractionated by high-performance liquid chromatography, and one fraction with antichemotactic activity contained the bactericidal protein human neutrophil protein 1 (HNP-1). We showed that HNP-1 suppresses PMN migration to formyl-methionyl-leucyl-phenylalanine but not to interleukin 8.  相似文献   
84.
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions.  相似文献   
85.
Alcohol use disorders (AUDs) impact millions of individuals and there remain few effective treatment strategies. Despite evidence that neuronal nicotinic acetylcholine receptors (nAChRs) have a role in AUDs, it has not been established which subtypes of the nAChR are involved. Recent human genetic association studies have implicated the gene cluster CHRNA3–CHRNA5–CHRNB4 encoding the α3, α5, and β4 subunits of the nAChR in susceptibility to develop nicotine and alcohol dependence; however, their role in ethanol-mediated behaviors is unknown due to the lack of suitable and selective research tools. To determine the role of the α3, and β4 subunits of the nAChR in ethanol self-administration, we developed and characterized high-affinity partial agonists at α3β4 nAChRs, CP-601932, and PF-4575180. Both CP-601932 and PF-4575180 selectively decrease ethanol but not sucrose consumption and operant self-administration following long-term exposure. We show that the functional potencies of CP-601932 and PF-4575180 at α3β4 nAChRs correlate with their unbound rat brain concentrations, suggesting that the effects on ethanol self-administration are mediated via interaction with α3β4 nAChRs. Also varenicline, an approved smoking cessation aid previously shown to decrease ethanol consumption and seeking in rats and mice, reduces ethanol intake at unbound brain concentrations that allow functional interactions with α3β4 nAChRs. Furthermore, the selective α4β2* nAChR antagonist, DHβE, did not reduce ethanol intake. Together, these data provide further support for the human genetic association studies, implicating CHRNA3 and CHRNB4 genes in ethanol-mediated behaviors. CP-601932 has been shown to be safe in humans and may represent a potential novel treatment for AUDs.  相似文献   
86.
Fibroblast activation protein-α (FAP) is a cell surface, serine protease of the post-prolyl peptidase family that is expressed in human breast cancer but not in normal tissues. Previously, we showed that FAP expression increased tumor growth rates in a mouse model of human breast cancer. Here the role of the proteolytic activities of FAP in promoting tumor growth, matrix degradation and invasion was investigated. Mammary fat pads of female SCID mice were inoculated with breast cancer cells that express FAP and the mice treated with normal saline or Val-boroPro (talabostat); Glu-boroPro (PT-630); or 1-[[(3-hydroxy-1-adamantyl)amino]acetyl]-2-cyano-(S)-pyrrolidine (LAF-237) that inhibit prolyl peptidases. Other mice were injected with breast cancer cells expressing a catalytically inactive mutant of FAP and did not receive inhibitor treatment. PT-630 and LAF-237 did not slow growth of tumors produced by any of the three cell lines expressing FAP. Talabostat slightly decreased the growth rates of the FAP-expressing tumors but because PT-630 and LAF-237 did not, the growth retardation was likely not related to the inhibition of FAP or the related post-prolyl peptidase dipeptidyl peptidase IV. Breast cancer cells expressing a catalytically inactive mutant of FAP (FAPS624A) also produced tumors that grew rapidly. In vitro studies revealed that cells expressing wild type FAP or FAPS624A degrade extracellular matrix (ECM) more extensively, accumulate higher levels of matrix metalloproteinase-9 (MMP-9) in conditioned medium, are more invasive in type I collagen gels, and have altered signaling compared to control transfectants that do not express FAP and form slow growing tumors. We conclude that the proteolytic activity of FAP participates in matrix degradation, but other functions of the protein stimulate increased tumor growth.  相似文献   
87.
The categorical underpinnings of the current diagnostic nomenclature have been the subject of repeated criticism. Recently, researchers have proposed several alternatives to the current system, including hybrid models of combined diagnostic categories and symptom dimensions. In the present study, we investigated the symptoms associated with a hybrid model of social phobia. The study included (a) the development of the initial set of symptom dimensions, generation of an item pool, and review by an expert panel, and (b) data collection and component analysis of the item pool to determine the structure of the symptoms. Six separate theoretically relevant symptom dimensions were identified. Implications of these findings on the development of a new hybrid model of social phobia were discussed.  相似文献   
88.
89.
Aim: To describe the establishment of a multicomponent, phase‐specific, early intervention service for young people experiencing psychosis. Methods: The Recovery and Prevention of Psychosis Service commenced streamed clinical service delivery in November 2004, providing comprehensive case management for up to 3 years within Victoria's largest metropolitan health service. It delivers phase‐oriented treatment focusing on early detection, recovery and relapse prevention, and minimizing disability and secondary comorbidity. The combined programme covers training and professional development, data collection and evaluation, specialist intervention services, group programme work and community development. Results: Of the first 151 clients, 70.2% were male, the average age at first presentation was 20.9 years, 15% were under 18 at first contact and 67% required inpatient admission at least once. Mean age at first contact was 20.84 years for those requiring inpatient services and 70% admitted were male. The average length of stay was 25.69 days and 23% were secluded, with an average of 2.1 seclusions. A large percentage of Recovery and Prevention of Psychosis Service clients (81%) required involuntary treatment, a significantly greater proportion of admitted patients were on Community Treatment Orders compared to those never admitted (22.5% cf. 4.1%; P = 0.04) and 92% of those admitted subsequently relapsed compared to 8% of those not admitted (P = 0.02). Conclusions: Recovery and Prevention of Psychosis Service is successfully developing a fully integrated first episode service. Recent developments include expanding the period of care up to 5 years for selected patients, the recruitment of a health promotions officer and planning for the development of a youth inpatient unit.  相似文献   
90.
Carrizo GJ  Wu R  Cui X  Dwivedi AJ  Simms HH  Wang P 《Surgery》2007,141(2):245-253
BACKGROUND: Recent studies have shown that adrenomedullin (AM) and AM-binding protein-1 (AMBP-1) possess anti-inflammatory properties in sepsis. We hypothesized that administration of AM/AMBP-1 after gut ischemia-reperfusion (I/R) downregulates inflammatory cytokines and attenuates tissue injury. METHODS: Male Sprague-Dawley rats (275-325 g) were used. Gut ischemia was induced by placing a microvascular clip across the superior mesenteric artery (SMA) for 90 minutes. Upon release of the SMA clamp, the animals were treated by AM (12 microg per kilogram of body weight) and AMBP-1 (40 microg per kilogram of body weight) in combination, or vehicle (1 mL 0.9% NaCl) over 30 minutes via a femoral vein catheter. The animals undergoing sham operation or ischemia for 90 minutes only, did not receive AM/AMBP-1 treatment. At 60 minutes after the completion of the treatment (ie, 90 minutes after reperfusion), blood samples were collected. Plasma AM and AMBP-1 were measured by radioimmunoassay and Western blot analysis, respectively. Serum levels of TNF-alpha, interleukin (IL)-1beta, IL-6, IL-10, transaminases (ie, alanine aminotransaminase, aspartate aminotransaminase), lactate, and creatinine were determined with the use of enzyme-linked immunosorbent assay and other standard methods. In additional groups of animals, the 10-day survival rate was recorded after gut I/R. RESULTS: Ischemia alone was sufficient to downregulate both AM and AMBP-1. Unlike AMBP-1 that remained decreased, AM levels increased significantly after reperfusion. I/R but not ischemia alone significantly increased serum levels of inflammatory cytokines. Moreover, I/R-induced tissue injury was evidenced by increased levels of transaminases, lactate, and creatinine. Administration of AM/AMBP-1 after ischemia, however, markedly reduced cytokine levels, attenuated tissue injury, and improved survival. CONCLUSIONS: AM/AMBP-1 may be a novel treatment to attenuate the reperfusion injury after gut ischemia.  相似文献   
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