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21.
BACKGROUND: Advanced glycation end products (AGEs) have biological properties that may contribute to the premature cardiovascular mortality of haemodialysis patients. This study examines the hypothesis that low molecular weight forms of fluorescent AGEs (LMW fluorescence) predict mortality in haemodialysis patients. METHODS: The LMW fluorescence was measured in 85 patients treated with chronic haemodialysis and prospectively followed for 4 years. The primary outcome of all-cause mortality was assessed using Cox proportional hazards regression model. RESULTS: At the end of the follow-up period 37 (44%) patients died. The median LMW fluorescence level was 24.2 arbitrary units (range: 10.6-148.1 AU) and the receiver operator characteristic (ROC) curve cut-off for mortality was 37.0 AU. The LMW fluorescence predicted death both as a binary variable at the ROC cut-off, and as a continuous log-transformed variable when adjusted for age, albumin and C-reactive protein (CRP). Adjusted for age, albumin and CRP, the hazard ratio for mortality was 3.05 (1.41-6.60, P = 0.005) for LMW fluorescence as a binary variable and 2.71 per log unit (1.37-5.38, P = 0.004) as a continuous log-transformed variable. CONCLUSION: The low molecular weight forms of AGEs predict mortality in patients receiving chronic haemodialysis, and may be important in the mechanisms leading to atherosclerosis and inflammation in such patients.  相似文献   
22.
BACKGROUND: Anthracycline cardiotoxicity is increased by the contemporaneous administration of trastuzumab. The mechanism by which it occurs is as yet unknown. The aim of this study was to evaluate whether trastuzumab modifies the pharmacokinetics of epirubicin and its metabolites. PATIENTS AND METHODS: Women with HER2-positive metastatic breast cancer were treated with epirubicin 75 mg/m(2) i.v. bolus followed by docetaxel 75 mg/m(2) in a 1-h infusion, every 3 weeks for six cycles, and trastuzumab (once at 4 mg/m(2), then 2 mg/m(2) weekly thereafter) in a 30-min infusion. Epirubicin pharmacokinetic data of seven patients were evaluated at the first cycle of therapy (baseline, with trastuzumab administered 24 h after epirubicin), and at the sixth cycle (i.e. 15 weeks after baseline, with trastuzumab administered immediately before epirubicin). RESULTS: No pharmacokinetic change in the parent compound epirubicin was detected. The area under the plasma concentration-time curve (AUC(0-24 h)) was 1230 +/- 318 [mean +/- standard deviation (SD)] at the first cycle and 1287 +/- 385 h. micro g/l at the sixth. The mean (+/-SD) maximum plasma concentration (C(max)) and the terminal elimination half-life at the first cycle (1303 +/- 490 micro g/l and 12.5 +/- 3.1 h, respectively) were similar to those obtained at the sixth cycle (1229 +/- 580 micro g/l and 11.5 +/- 2.9 h, respectively). Pharmacokinetic data of epirubicin metabolites evaluated at the first and sixth cycle of chemotherapy were superimposable without any statistical difference. CONCLUSION: Enhanced anthracycline cardiotoxicity related to trastuzumab administration was not linked to pharmacokinetic interferences with epirubicin and its metabolites.  相似文献   
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目的 探讨高级糖化终产物与糖尿病并发症的关系。方法 采用本实验室自行研制的竞争性酶联免疫吸附分析方法,测定了糖尿病有并发症组病人血浆95例,糖尿病无并发症组人血浆65例,正常对照65例。结果:在糖尿病有并发症组中,高级糖化终产物(AGEs)浓度[(6.625(1.691)U/mL,n=95]明显高于糖尿病无并发症组[(5.904(2.071)U/mL,n=65,P=0.017],也明显高于正常人组[(5.337(1.138,n=65,p〈0.005]。以有无并发症为应变量进行多元logistic回归分析显示,血浆AGEs浓度〉6.085U/ml者,糖尿病并发症发生的危险性增加(OR值为2.989,95%可信限为1.407—6.350)。多元逐步线性回归显示:糖尿病病程、冠心病史与血浆AGEs浓度之间有线性关系。结论血浆AGEs浓度是糖尿病发生并发症的独立危险因素。  相似文献   
25.
In screening programmes it is important to assess a preliminary effectiveness of the screening method as soon as possible in order to forecast survival figures. In March 1981 a controlled single-view mammographic screening trial for breast cancer was started in the south of Stockholm. The population invited for screening mammography consisted of 40,000 women aged 40–64 years, and 20,000 women served as a well-defined control group. The main aim of the trial was to determine whether repeated mammographic screening could reduce the mortality in the study population (SP) compared to the control population (CP).The cumulative number of advanced mammary carcinomas in the screening and the control populations from the first five years of screening have shown a tendency towards more favourable stages in the screened population aged 40–64 years. A breakdown by age suggests an effect in age group 50–59 years, but not yet in age groups 40–49 and 60–64 years.When comparing the rates of stage II+ cancer, an increased number is found in the study group. As the total rate of breast cancer is higher in SP than in CP, there ought to be a concealed group of stage II+ cancers in the CP which makes the comparison biased. A new approach has been designed, where an estimation of the hidden number of stage II+ cancers in CP is added to the clinically detected cases, and in this respect a comparison has shown a decrease in the cumulative number of advanced cancers in the SP in relation to the CP (p<0.05). According to this it could be important to add the estimated number of undetected, hidden cases in the control group in order to utilize the difference in detection rate in the screening- and control group respectively.  相似文献   
26.
目的:探讨终末糖基化产物在糖尿病动脉粥样硬化(AS)形成中的作用机理。 方法: 分离正常人脐静脉内皮细胞(HUVECs),将终末糖基化终产物(AGE)修饰的人血清白蛋白(AGE-HSA)、人血清白蛋白(HSA)与HUVECs在体外共同培养,并用荧光单克隆抗体染色,流式细胞仪定量检测细胞间粘附分子-1(ICAM-1)、血管细胞粘附分子-1(VCAM-1)的表达。 结果: 正常人HUVEC表达ICAM-1和VCAM-1。AGE-HSA能以时间和剂量依赖的方式上调ICAM-1、VCAM-1的表达(P<0.05),而HSA对HUVECs上述粘附分子的表达均无影响。 结论: AGE能上调HUVECs粘附分子的表达,从而促进AS时单核/巨噬细胞的浸润。  相似文献   
27.
目的探讨紫杉醇联合草酸铂、卡培他滨三药方案治疗晚期转移性鼻咽癌的疗效及不良反应。方法2002年1月至2005年1月,110例晚期转移性鼻咽癌病人入组:试验组55例患者.第1天应用紫杉醇135mg/m^2、草酸铂130mg/m。静脉滴注,口服卡培他滨1650mg/m^2/d,连服l-14d,每3周为一个周期,连用2-4个周期;对照组55例患者,第1-5天应用DDP 20mg/m^2、5-Fu 0.5g/m^2静脉注射,3周为一个周期,连用2-4个周期;治疗结束2-4周后评价疗效。结果试验组疗效可评价55例,对照组疗效可评价53例。试验组与对照组有效率分别为(CR+PR)50.9%(28例)和32.1%(17例),两者差异有统计学意义(P〈0.05)。试验组和对照组中位生存时间为10.6个月和8.6个月,两者差异有统计学意义(t〈0.05)。安全性方面:试验组Ⅳ反应主要为手足综合征8例(14.5%)、骨髓抑制2例(3.6%)和消化道毒性4例(7.3%);对照组Ⅳ反应主要为消化道毒性8例(15.1%)、骨髓抑制2例(3.8%)。结论紫杉醇联合草酸铂、卡培他滨三药方案对晚期转移性鼻咽癌的疗效较DDP+5-Fu有优势,且不良反应可以耐受。  相似文献   
28.
目的:探讨阿魏酸钠(SF)对糖尿病(DM)大鼠肾脏非酶糖基化和氧化的影响。方法:对链脲佐菌素(STZ)诱导的DM大鼠灌胃给予SF 110 mg·kg-1·d-1,治疗8周,测定各组大鼠肾重/体重、肌酐清除率(Ccr)、24 h尿蛋白定量、血清和肾皮质果糖胺(FMN)、血清和肾皮质丙二醛(MDA)含量及抗氧化酶活性,并分别测定肾皮质糖基化终产物(AGEs)含量,观察肾脏病理改变。结果:糖尿病对照组(DM组)大鼠肾重/体重、Ccr、24 h尿蛋白定量、血清FMN、肾皮质FMN和AGEs显著高于正常对照组(N组);SF治疗组(SF组)肾重/体重、Ccr、24 h尿蛋白定量、血清FMN和肾皮质AGEs显著低于DM组;DM组大鼠肾皮质和血清超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性显著低于N组,MDA含量显著高于N组,SF治疗组大鼠肾皮质和血清SOD、CAT活性显著高于DM组,MDA含量显著低于DM组:DM组大鼠肾脏病理改变异常显著,SF组的肾脏病理学改变轻于DM组大鼠。结论: SF通过保护肾脏抗氧化酶,减轻氧化应激,抑制AGEs在肾脏的沉积对DM大鼠肾脏产生保护作用。  相似文献   
29.
目的探讨晚期氧化蛋白(AOPP)在急性有机磷农药中毒(AOPP)患者中的临床意义。方法采用酶联免疫分析法(ELISA)动态检测90例有机磷农药中毒患者和30例健康对照者血清晚期氧化蛋白的含量,并探讨其与病情的相关性。结果AOPP患者血浆中晚期氧化蛋白含量发病后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。血清CRP的含量在患者中毒后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。在发病的第1天,AOPP患者血清晚期氧化蛋白和CRP的含量重度中毒组〉中度中毒组〉轻度中毒组与健康对照组比较,P均〈0.01。在第1天,AOPP患者的病情程度即MODS的评分值与血清晚期氧化蛋白和CRP的含量均呈明显的正相关性(r1=0.590和r2=0.627,P均〈O.01),而血清晚期氧化蛋白和CRP的含量之间也呈明显的正相关性(r3=0.792,P〈0.01)。结论晚期氧化蛋白的含量随急性有机磷农药中毒患者的病情和炎症反应加重而升高。晚期氧化蛋白可能参与了有机磷农药中毒患者发生多脏器功能障碍的病理生理过程。  相似文献   
30.
The available data on the association between micronutrients in the blood and non-alcoholic fatty liver disease (NAFLD) are limited. To investigate the clinical implications of this relationship, we sought to identify the difference in the serum levels of vitamins A and E according to NAFLD status using data from the seventh Korea National Health and Nutrition Examination Survey. In this cross-sectional study of the Korean population, NAFLD and its severity were defined using prediction models. Differences in the prevalence and severity of NAFLD were analyzed according to serum retinol (vitamin A) and alpha (α)-tocopherol (vitamin E) levels. Serum levels of retinol and α-tocopherol were positively correlated with the prevalence of NAFLD. In most prediction models of the NAFLD subjects, serum retinol deficiency was significantly correlated with advanced fibrosis, while serum α-tocopherol levels did not differ between individuals with or without advanced fibrosis. Similar trends were also noted with cholesterol-adjusted levels of α-tocopherol. In summary, while circulating concentrations of retinol and α-tocopherol were positively associated with the presence of NAFLD, advanced liver fibrosis was only correlated with serum retinol levels. Our findings could provide insight into NAFLD patient care at a micronutrient level.  相似文献   
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