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31.
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   
32.
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   
33.
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   
34.
Background The role of the single nucleotide polymorphisms (SNPs) on positions 2677G>T/A and 3435C>T of the multi-drug-resistance gene 1 (MDR1) in inflammatory bowel disease (IBD) remains unclear. Aims To further elucidate the potential impact of MDR1 two-locus genotypes on susceptibility to IBD and disease behaviour. Patients and methods Three hundred eighty-eight German IBD patients [244 with Crohn’s disease (CD), 144 with ulcerative colitis (UC)] and 1,005 German healthy controls were genotyped for the two MDR1 SNPs on positions 2677G>T/A and 3435C>T. Genotype–phenotype analysis was performed with respect to disease susceptibility stratified by age at diagnosis as well as disease localisation and behaviour. Results Genotype distribution did not differ between all UC or CD patients and controls. Between UC and CD patients, however, we observed a trend of different distribution of the combined genotypes derived from SNPs 2677 and 3435 (χ2 = 15.997, df = 8, p = 0.054). In subgroup analysis, genotype frequencies between UC patients with early onset of disease and controls showed significant difference for combined positions 2677 and 3435 (χ2 = 16.054, df = 8, p = 0.034 for age at diagnosis ≥25, lower quartile). Herein the rare genotype 2677GG/3435TT was more frequently observed (odds ratio = 7.0, 95% confidence interval 2.5 – 19.7). In this group severe course of disease behaviour depended on the combined MDR1 SNPs (χ2 = 16.101, df = 6, p = 0.017 for age at diagnosis ≥25). No association of MDR1 genotypes with disease subgroups in CD was observed. Conclusions While overall genotype distribution did not differ, combined MDR1 genotypes derived from positions 2677 and 3435 are possibly associated with young age onset of UC and severe course of disease in this patient group.  相似文献   
35.
不同补锌方法对儿童免疫功能的影响   总被引:2,自引:0,他引:2  
研究不同补锌方法(补锌,补充微量营养素,补充锌加微量营养素)改善缺锌儿童免疫功能的作用,结果显示:实验10wk后,三个实验组缺锌儿童血清锌浓度明显升高,同时淋巴细胞刺激指数明显高于对照组,流式细胞仪检测细胞周期显示对照组G0/G1期细胞增多,而实验组S+G0/G1期细胞增多,细胞处于增殖活化状态。三组中又以锌+微量营养素作用效果最好。表明:锌和微量营养素单独使用均增强缺锌儿童的免疫功能,但锌和微量  相似文献   
36.
A 36 year-old infertile female developed a stage IV (FIGO) ovarian carcinoma consisting of a poorly differentiated Sertoli-Leydig cell tumour after receiving one course of ovulation induction with follicle stimulating hormone (FSH), human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG) followed by gonadotrophin-releasing hormone analogue (GnRHa). The patient died of liver metastasis and hepatic failure 4 1/2 months after first diagnosis, despite aggressive treatment consisting of debulking surgery and aggressive adjuvant chemotherapy.   相似文献   
37.

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.  相似文献   
38.
We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken.  相似文献   
39.
We have previously described a unique type of delta beta-thalassemia in a Chinese family characterized by increased expression of the G gamma and A gamma fetal globin genes in the absence of a large deletion in the beta-globlin gene cluster. Our earlier study of the beta-globin gene on this delta beta-thalassemia chromosome showed a promoter mutation in the TATA box. In this report, we describe the results of our study of the fetal globin domain of this delta beta-thalassemia chromosome. We have cloned a 13-kb DNA fragment that includes the G gamma and the A gamma genes and the 3' A gamma enhancer element of this delta beta-thalassemia chromosome. DNA sequence analysis of the G gamma and A gamma-globin genes including their promoters did not show any mutations, but analysis of the putative enhancer element downstream from the A gamma-globin gene showed a C to T substitution 2,401 nucleotides downstream from the A gamma cap site. We performed DNA linkage analysis to determine if this mutation is unique to this chromosome or represents a common polymorphism. Our linkage analysis showed that this mutation is not a common polymorphism and that it is also not an intrinsic part of the haplotype of the chromosome on which it was found. We also studied the interaction of nuclear proteins from erythroid and nonerythroid cells with the DNA sequences surrounding this mutation. We have shown by in vitro DNase I footprinting that this mutation falls within a region that is occupied by a novel DNA-binding protein that binds to this site in nuclear extracts from erythroid, but not nonerythroid cells. The binding of this nuclear protein to DNA appears to be dependent on GATA-1 binding to an adjacent GATA-1 site. We have also developed a new functional assay to compare the activity of the normal and mutant A gamma enhancer elements in erythroid cells. Analysis of the activity of the mutant enhancer shows that the mutation completely eliminates all enhancer activity in this assay. These findings suggest that this mutation of the A gamma enhancer on a chromosome that carries a partially inactivated beta-globin gene may be responsible for the increased expression of both gamma-globin genes seen in this condition.  相似文献   
40.
Interaction of platelet plasma membranes with thrombin-activated platelets   总被引:1,自引:0,他引:1  
Prasanna  HR; Edwards  HH; Phillips  DR 《Blood》1981,57(2):305-312
This study described the binding of platelet plasma membranes to either control or thrombin-activated platelets. Glycoproteins in plasma membranes isolated from human platelets were labeled by oxidation with periodate followed by reduction with [3H]NaBH4. Labeled membranes were incubated with either control or thrombin-activated platelets. The amount of membranes bound was measured by separating platelets with bound membranes from solution by rapid centrifugation through 27% sucrose and determining the amount of radioactivity associated with platelets. Five- to sevenfold more membranes bound to thrombin- activated platelets than to control platelets. This enhanced binding of labeled membranes was completely inhibited by an excess of unlabeled platelet membranes. Human erythrocyte membranes had little affinity for either washed or thrombin-activated platelets and therefore did not compete for platelet-membrane binding. Binding of platelet membranes to thrombin-treated platelets was inhibited by prior incubation of the platelets with PGI2 suggesting that the enhanced binding of membranes was to activated platelets. This study demonstrates that the purified platelet membranes have functional sites that can mediate membrane binding to platelets and that quantitation of membrane binding appears to reflect the increased aggregation capability of activated platelets.  相似文献   
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