冠心病人同型半胱氨酸水平的主要影响因素

目的　分析影响冠心病人血浆同型半胱氨酸水平的主要非遗传因素。方法　 16 4例住院冠心病患者 ,测定血浆同型半胱氨酸水平并分析其与血浆及全血叶酸、血浆维生素B12 、血清雌二醇浓度以及冠心病传统危险因素之间的关系。结果　血浆同型半胱氨酸水平与叶酸、维生素B12 水平呈负相关 ,男性血浆同型半胱氨酸浓度高于女性 [(2 0 74± 13 42 )× 10 -6mol/L比 (15 5 6± 8 16 )× 10 -6mol/L ,P <0 0 5 ],吸烟者高于不吸烟者 [(2 2 2 9± 15 18)× 10 -6mol/L比 (17 2 1± 9 5 4)× 10 -6mol/L ,P <0 0 5 ]。结论　叶酸、维生素B12 、性别和吸烟是影响冠心病患者血浆同型半胱氨酸水平的主要非遗传因素     

甲钴胺对冠心病患者的高同型半胱氨酸血症的影响

目的　研究血浆同型半胱氨酸 (hyperhomocysteinemia ,Hcy)与冠心病 (CHD)的关系及甲钴胺对其的影响。方法　运用高效液相色谱仪和荧光检测仪测定 6 0例CHD患者和 40例健康人血浆Hcy水平 ,并对 36例冠心病合并高Hcy血症的患者用甲钴胺进行干预治疗 ,一次 5 0 0 μg ,每日 3次 ,连用 6周 ,6周后再次测定其血浆Hcy水平。结果　CHD患者血浆Hcy水平 (2 4 0± 5 5 ) μmol/L显著高于正常对照组水平 (9 8± 2 9) μmol/L ,P <0 0 1,在 6 0例CHD患者中有 36例合并高Hcy血症 ,对这些患者进行甲钴胺干预治疗 6周后 ,发现较治疗前明显下降 (11 3± 3 1) μmol/L ,P <0 0 1。 结论　高Hcy血症与冠心病发病有关 ,甲钴胺可显著降低冠心病合并高Hcy血症患者的血浆Hcy水平。     

同型半胱氨酸与冠心病的相关性及其机制探讨

目的　探讨血浆同型半胱氨酸 (HCY)与冠心病 (CHD)的相关性、与CHD传统危险因素的关系及其致CHD的机制。方法　分别测定CHD患者 (10 5例 )及对照组 (32例 )血中HCY、内皮素(ET)、一氧化氮 (NO)、一氧化氮合酶 (NOS)水平及血脂各参数。结果　CHD组高同型半胱氨酸血症(HHCY)的发生率明显高于对照组 (49 5 %比 9 4 % ,P <0 0 1) ,CHD组HCY水平明显高于对照组[(15 2 9± 5 14 ) μmol L比 (10 6 6± 2 78) μmol L ,P <0 0 1]。多元回归分析显示HCY对CHD的相对危险度 (RR)为 1 397(95 %可信区间 :1 137～ 1 6 4 5 ,P <0 0 1) ,表明HCY为CHD的独立危险因素。HCY与年龄、甘油三酯有关 (P <0 0 5 )。HCY与ET呈正相关 (P <0 0 1) ,而与NO、NOS呈负相关 (P <0 0 1)。结论　HHCY是CHD的独立危险因素。HCY可能损伤血管内皮细胞 ,使血管内皮功能失调。     

高同型半胱氨酸血症与2型糖尿病慢性并发症的关系

目的　探讨 2型糖尿病患者血浆同型半胱氨酸 (Hcy)水平与慢性并发症的关系。　方法　应用高效液相色谱仪和荧光检测仪测定 2 16例 2型糖尿病患者和 89名正常对照者的血浆总同型半胱氨酸 (tHcy)水平 ,分析患者组血浆tHcy水平与慢性并发症之间的关系。 　结果　 (1)患者组血浆tHcy水平高于正常对照组 [(16 .0± 6 .3) μmol/Lvs (11.7± 2 .2 ) μmol/L ,P <0 .0 1];患者组中35 %存在高Hcy血症 (tHcy >16 .2 μmol/L) ,而正常对照组仅 7% (P <0 .0 1)。 (2 )患者组中的高Hcy组 [n =75 ,tHcy为 (2 3.7± 7.4 ) μmol/L]其慢性并发症的发生率为 6 7% ,而正常Hcy组 [n =14 1,tHcy为 (11.6± 2 .5 ) μmol/L]为 4 0 % (P <0 .0 1)。高Hcy组中高血压、冠心病、脑血管病变、下肢血管病变及肾病的发生率均高于正常Hcy组 ,其中以冠心病发生率差异尤为显著 (43%vs 2 3% ,P <0 .0 0 1) ,而视网膜病变及神经病变的发生率则无明显差异。 (3)相关分析显示 ,2型糖尿病患者血浆tHcy水平与年龄、尿白蛋白排泄率呈正相关 (r =0 .36 ,P =0 .0 0 0 9;r =0 .2 7,P =0 .0 184 ) ,与肌酐清除率、血叶酸水平呈负相关 (r =- 0 .5 3,P =0 .0 0 0 3;r =- 0 .2 5 ,P =0 .0 137)。　结论　高Hcy血症与 2型糖尿病的大血管病变及肾脏病变     

冠心病稳定性心绞痛患者冠状动脉造影术后血浆内皮素-1水平升高意义

目的　观察稳定性心绞痛患者冠状动脉造影时血浆内皮素 - 1水平变化及其临床意义。方法　根据冠状动脉造影结果将 6 4例患者分为两组 ,冠心病稳定性心绞痛组 (SA组 )与冠脉正常组 (正常对照组 )。冠状动脉造影前及冠状动脉造影后即刻抽取血液标本测定血浆内皮素 - 1水平并记录动脉收缩压与舒张压。结果　两组冠状动脉造影所耗时间无明显差异 (P >0 0 5 ) ,冠状动脉造影前及冠状动脉造影后即刻平均动脉压在SA组分别为 137/ 86mmHg和 14 1/ 90mmHg(P <0 0 5 ) ,正常对照组分别为 136 / 85mmHg和 138/ 87mmHg(P >0 0 5 ) ;冠状动脉造影前及冠状动脉造影后即刻血浆内皮素 - 1水平在SA组分别为 5 5 1± 1 2 8ng/L和 6 94± 1 37ng/L(P <0 0 1) ,正常对照组分别为 5 10± 1 13ng/L和 5 14± 1 16ng/L(P <0 0 5 )。 结论　冠状动脉造影可激发冠心病稳定性心绞痛患者的内皮细胞反应 ,导致血浆内皮素 - 1水平升高。     

系统性红斑狼疮与高同型半胱氨酸血症的临床研究

目的　观察系统性红斑狼疮 (SLE)患者血浆中同型半胱氨酸 (Hcy)水平 ,分析影响Hcy的因素和某些心血管因素的变化。 方法　测定 2 7例SLE和 31名正常对照的Hcy、维生素B12 、叶酸、C反应蛋白 (CRP)、氧化低密度脂蛋白 (oxLDL)、一氧化氮 (NO)、丙二醛 (MDA)的水平和亚甲基四氢叶酸还原酶 (MTHFR)基因 6 77位的多态性。结果　①SLE组Hcy水平明显较对照组高 ,其差异有显著性 [SLE组 (19± 7) μmol/L ,对照组 (12± 4 ) μmol/L ,P <0 0 0 1];②Hcy与维生素B12 、叶酸呈负相关 ,相关系数分别为 - 0 76 7和 - 0 6 7,P <0 0 0 0 1;③MTHFR基因 6 77位CT的突变使Hcy水平升高 [CC型 (12 8± 6 2 ) μmol/L ,CT型 (16 0± 2 1) μmol/L ,TT型 (18 9± 5 7) μmol/L ,P<0 0 0 1];TT基因型是高Hcy血症的易感基因 ,相对危险度 (RR) =31 4 9,P <0 0 5 ;TT基因型是SLE的易感基因 ,RR =6 913,P <0 0 5 ;④Hcy水平与NO、MDA、oxLDL呈正相关 ,并与CRP呈正相关。结论　①SLE患者普遍有高Hcy血症。②导致高Hcy血症的原因包括叶酸、维生素B12 的水平降低和MTHFR基因的突变 ,TT型基因是Hcy异常升高的易感基因。③TT型基因也是SLE的易感基因。④高Hcy血症可能通过损伤血管内皮 ,大量产生氧自由基 ,加速低密度     

卡维地洛对冠状动脉成形术后患者外周血内皮素及一氧化氮的影响

为探讨卡维地洛对冠心病患者经皮腔内冠状动脉成形术后血中内皮素及一氧化氮的影响 ,本文选择经冠状动脉造影证实有一支或二支以上≥ 70 %狭窄需行经皮腔内冠状动脉成形术的患者 5 1例 ,随机分成卡维地洛组2 8例和常规治疗组 2 3例 ,测定经皮腔内冠状动脉成形术前后及用药前后外周血内皮素及一氧化氮含量。结果发现 ,经皮腔内冠状动脉成形术后血中内皮素 (卡维地洛组为 84 .9± 14 .7μg/L、常规治疗组为 85 .6± 15 .4 μg/L)较术前 (卡维地洛组为 70 .6± 12 .8μg/L、常规治疗组为 71.5± 13.3μg/L)增高 ;一氧化氮 (卡维地洛组为 5 0 .3± 13.4μmol/L、常规治疗组为 5 0 .9± 12 .6 μmol/L)较术前 (卡维地洛组为 6 2 .9± 14 .2 μmol/L、常规治疗组为 6 3.5± 13.1μmol/L)降低 (P <0 .0 5 ) ;卡维地洛组内皮素为 74 .6± 15 .6 μg/L ,较用药前 (84 .4± 14 .9μg/L)降低 ;一氧化氮为 6 2 .7± 12 .8μmol/L ,较用药前 (5 1.6± 12 .5 μmol/L)增高 (P <0 .0 5 ) ,常规治疗组内皮素和一氧化氮观察两周均无显著变化 (P >0 .0 5 )。提示卡维地洛具有改善冠状动脉成形术后血管内皮功能的作用     

正常人餐后甘油三酯动态代谢对血清一氧化氮和血浆内皮素1的影响

为探讨正常人脂肪负荷后甘油三酯动态代谢对血清一氧化氮和血浆内皮素 1浓度的影响 ,取 2 0例正常人标准脂肪餐前 (0h)、餐后 2、4、6和 8h外周静脉血 ,分离血清 ,测定甘油三酯、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、载脂蛋白AⅠ和载脂蛋白B水平 ,放射免疫法测定血浆内皮素 1浓度 ,比色法测定血清一氧化氮相对浓度 ,计算一氧化氮 /内皮素 1比值。结果发现 ,餐后 2h血清甘油三酯浓度显著高于餐前 (2 .19± 0 .16比 1.161.16± 0 .11mmol/L ,P <0 .0 5 ) ,4h达到高峰 (3.34± 0 .37mmol/L) ,8h恢复至餐前水平。餐后 2h血浆一氧化氮浓度存在一过性升高 (61.5 8± 5 .97比 42 .5 0± 7.42ng/L ,P <0 .0 5 ) ,6、8h又显著降低 (37.60± 5 .71比 61.5 8± 5 .97ng/L ;30 .76± 5 .0 1比 61.5 8± 5 .97ng/L ,P <0 .0 5 )。餐后 2h内皮素 1浓度较餐前显著降低(99.0 8± 16.5 5比 114.2 2± 16 .45ng/L ,P <0 .0 5 ) ,餐后 6、8h较 2h显著升高 (113.82± 19.80比 99.0 8± 16 .5 5ng/L ,12 1.0 2± 19.5 5比 99.0 8± 16.5 5ng/L ,P <0 .0 5 ) ,餐后 8h较 4h高 (12 1.0 2± 19.5 5比 10 3.45± 19.87ng/L ,P <0 .0 5 )。同样 ,一氧化氮 /内皮素 1比值在餐后 2h存在高峰 (0 .78± 0 .13比 0 .46±     

同型半胱氨酸血症血小板及内皮细胞活性的体内研究

目的　探讨轻中度同型半胱氨酸血症作为心血管疾病新的重要危险因子对血小板活性 ,内皮细胞功能及体内氧化状态的影响。方法　应用安慰剂自身对照交叉设计方法 ,蛋氨酸负荷实验诱导 15个正常个体轻中度同型半胱氨酸血症 ,检测轻中度同型半胱氨酸血症对血小板纤维蛋白原结合及血小板膜P选择素表达 ,内皮细胞依赖的血管舒张 ,内皮细胞因子及体内氧化指标硫巴比妥酸反应物和结合二烯的影响。结果　蛋氨酸负荷后 ,血浆同型半胱氨酸水平显著升高 [(6 5 6±1 83) μmol L比 (15 2 0± 3 0 1) μmol L ,P <0 0 0 1],并伴随范登伯因子 ,血浆凝血酶活化因子抑制剂 1和血浆 β 血栓球蛋白水平的显著升高 [分别为 (6 8± 33) %比 (86± 13) % ,P <0 0 5 ,(35± 11)ng ml比(6 9± 38)ng ml,P <0 0 5 ,(78± 5 0 )U ml比 (12 5± 5 0 )U ml,P =0 0 5 8],而安慰剂负荷后则无变化。然而内皮细胞依赖的血管舒张和氧化状态无论在蛋氨酸负荷还是在安慰剂负荷前后均无变化。结论　轻中度同型半胱氨酸血症可导致人体血小板活性及内皮细胞功能的改变 ,提示同型半胱氨酸血症对动脉粥样硬化的发生、发展起重要作用。     

慢性肾衰竭患者同型半胱氨酸血症与动脉粥样硬化的关系

目的　研究慢性肾功能衰竭 (CRF)患者血浆同型半胱氨酸 (Hcy)水平与动脉粥样硬化及动脉舒张功能障碍的关系。方法　选择CRF患者 197例和健康对照 5 3例 ,采用荧光偏振免疫分析法测定血浆总同型半胱氨酸 (tHcy)水平 ,用高分辨超声技术检测颈总动脉内膜 中层厚度 (IMT)、粥样硬化斑块以及反应性充血后和含服硝酸甘油后肱动脉内径的变化率。结果　CRF患者高同型半胱氨酸血症发生率为 84 4 % ,其血浆tHcy水平 [(2 3 5 6± 11 91) μmol/L]明显高于正常对照组 [(7 97±2 6 5 ) μmol/L](P <0 0 1)。CRF患者平均IMT值和颈动脉粥样斑块检出率均明显高于年龄匹配的正常对照组 ,肱动脉反应性充血后内径增加率 (Dh)为 (4 0 5± 3 81) % ,含服硝酸甘油后内径增加率 (Dn)为 (4 94± 4 2 8) % ,均分别明显低于正常对照组Dh的 (8 81± 6 15 ) %和Dn 的 (11 72± 7 6 4 ) % (P <0 0 1)。按动脉粥样硬化严重程度分级 ,病变越重者血浆tHcy水平越高。多因素逐步回归分析显示 ,影响颈总动脉IMT的因素按影响程度依次为血浆tHcy、透析时间和年龄 (RR =0 4 84 ,P <0 0 0 1) ;影响Dh 的因素为血浆tHcy水平、年龄、透析时间和血清总胆固醇水平 (RR =0 2 6 3,P <0 0 0 1) ;影响Dn 的因素为年龄和血浆tHcy水平 (RR =0 2     

Electrochemical Recovery and Behaviors of Rare Earth (La,Ce, Pr,Nd, Sm,Eu, Gd,Tb, Dy,Ho, Er,Tm, and Yb) Ions on Ni Sheets

The electrochemical behaviors of rare earth (RE) ions have extensively been studied because of their high potential applications to the reprocessing of used nuclear fuels and RE-containing materials. In the present study, we fully investigated the electrochemical behaviors of RE(III) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) ions over a Ni sheet electrode in 0.1 M NaClO₄ electrolyte solution by cyclic voltammetry between +0.5 and −1.5 V (vs. Ag/AgCl). Amperometry electrodeposition experiments were performed between −1.2 and −0.9 V to recover RE elements over the Ni sheet. The successfully RE-recovered Ni sheets were fully characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The newly reported recovery data for RE(III) ions over a metal electrode provide valuable information on the development of the treatment methods of RE elements.     

Clinical trials update: highlights of the scientific sessions of The American College of Cardiology 2002: LIFE,DANAMI 2, MADIT-2, MIRACLE-ICD,OVERTURE, OCTAVE,ENABLE 1 & 2, CHRISTMAS,AFFIRM, RACE,WIZARD, AZACS,REMATCH, BNP trial and HARDBALL

This article continues a series of reports updating recent research developments of particular interest to personnel involved in the treatment and management of patients with heart failure. This is a summary of selected presentations made at the American College of Cardiology 51st Annual Scientific Session held in Atlanta on 17-20 March 2002. Reports of the following clinical studies are included: LIFE, DANAMI 2, MADIT-2, MIRACLE-ICD, OVERTURE, OCTAVE, ENABLE 1 & 2, CHRISTMAS, AFFIRM, RACE, WIZARD, AZACS, REMATCH, BNP trial and HARDBALL.     

Prevalence,Self-Awareness,Treatment, and Control of Hypertension in Lhasa,Tibet

To investigate the prevalence, self-awareness, and treatment of hypertension in Lhasa, Tibet, a total of 1370 native Tibetan aged ≥18 years were selected, using stratified proportional sampling. The study showed that the prevalence of hypertension was 51.2%, significantly higher in men (56.0%) than in women (48.0%) (P = .004). The hypertension prevalence increased with increasing age (77.8% in 60–74 y and 82.5% in ≥75 y groups) and was higher in urban, suburban, or agricultural area than in pastoral area (P < .001). The self-awareness, treatment, and control rate of hypertension were 63.5%, 24.3% and 7.7%, respectively. In multivariable regression analysis, age, urban residence, amount of daily intake of fat and oil, and body mass index <18.5 kg/m² were independently associated with hypertension. In conclusion, hypertension was highly prevalent among native Tibetan people in Lhasa, and the rates of self-awareness, treatment, and control of hypertension were low.     

Lack of effect of colesevelam HCl on the single-dose pharmacokinetics of aspirin,atenolol, enalapril,phenytoin, rosiglitazone,and sitagliptin

Aims

Drug interactions with bile acid sequestrants are primarily due to the potential of these agents to bind to concomitant drugs. Six clinical studies were performed to determine the effects of colesevelam on the pharmacokinetics of aspirin, atenolol, enalapril, phenytoin, rosiglitazone, and sitagliptin.

Methods

All six studies enrolled healthy subjects aged 18–45 years. The phenytoin study used a single-dose, three-period crossover design (phenytoin alone, phenytoin simultaneously with colesevelam, and phenytoin 4 h before colesevelam). The other studies used a two-period crossover design (test drug alone and test drug simultaneously with colesevelam). Colesevelam (3750 mg once daily) was dosed throughout the pharmacokinetic sampling period. After each single dose of the test drug, serial blood samples were collected for determination of plasma drug concentrations and calculation of pharmacokinetic parameters.

Results

For all six test drugs, 90% CIs for geometric least-squares mean ratios of AUC and C_max for the measured analytes were within specified limits, indicating no interaction between the test drug and colesevelam.

Conclusions

Aspirin, atenolol, enalapril, rosiglitazone, and sitagliptin may be taken with colesevelam. Although the phenytoin study indicated no pharmacokinetic interaction, phenytoin should continue to be taken ≥4 h before colesevelam in accordance with current prescribing information.     

Biliary microlithiasis,sludge,crystals,microcrystallization,and usefulness of assessment of nucleation time

BACKGROUND:The process of microcrystallization,its sequel and the assessment of nucleation time is ignored.This systematic review aimed to highlight the importance of biliary microlithiasis,sludge,and crystals,and their association with gallstones,unexplained biliary pain,idiopathic pancreatitis, and sphincter of Oddi dysfunction.DATA SOURCES:Three reviewers performed a literature search of the PubMed database.Key words used were"biliary microlithiasis","biliary sludge","bile crystals","cholesterol crystallisation","bile microscopy","microcrystal formation of bile","cholesterol monohydrate crystals","nucleation time of cholesterol","gallstone formation","sphincter of Oddi dysfunction"and"idiopathic pancreatitis".Additional articles were sourced from references within the studies from the PubMed search.RESULTS:We found that biliary microcrystals account for almost all patients with gallstone disease,7%to 79%with idiopathic pancreatitis,83%with unexplained biliary pain, and 25%to 60%with altered biliary and pancreatic sphincter function.Overall,the detection of biliary microcrystals in gallstone disease has a sensitivity ranging from 55%to 87%and a specificity of 100%.In idiopathic pancreatitis,the presence of microcrystals ranges from 47%to 90%.A nucleation time less than 10 days in hepatic bile or ultra-filtered gallbladder bile has a specificity of 100%for cholesterol gallstone disease.CONCLUSIONS:Biliary crystals are associated with gallstone disease,idiopathic pancreatitis,sphincter of Oddi dysfunction, unexplained biliary pain,and post-cholecystectomy biliary pain.Pathways of cholesterol super-saturation,crystallisation, and gallstone formation have been described with scientificsupport.Bile microscopy is a useful method to detect microcrystals and the assessment of nucleation time is a good method of predicting the risk of cholesterol crystallisation.     

Clinical trials update from the American College of Cardiology 2008: CARISMA, TRENDS, meta-analysis of Cox-2 studies, HAT, ON-TARGET, HYVET, ACCOMPLISH, MOMENTUM, PROTECT, HORIZON-HF and REVERSE

This article provides information and a commentary on trials relevant to the pathophysiology, prevention and treatment of heart failure, presented at the American College of Cardiology. Unpublished reports should be considered as preliminary data, as analyses may change in the final publication. CARISMA investigated the use of implantable loop recorders for detecting life-threatening arrhythmias in patients with LVSD after MI and found that brady- and ventricular tachy-arrhythmias predicted an adverse prognosis. The TRENDS study showed that the burden of atrial fibrillation detected by pacemakers or defibrillators predicted the risk of embolic events but not with sufficient precision to justify changes in anti-thrombotic management. A meta-analysis of six trials reported an increased cardiovascular risk associated with celecoxib, particularly for heart failure, which was related to dose and baseline cardiovascular risk. The HAT study failed to show a benefit of providing post-MI patients with a home defibrillator. MOMENTUM, a study of a device designed to augment aortic blood flow, was stopped early due to increased bleeding risk. Results from PROTECT support the use of rolofylline 30 mg/day in acute heart failure, a definitive study is now underway. Istaroxime, an agent that appears to have both inotropic and lusitropic effects, improved haemodynamics when added to standard therapy in patients stabilised after admission with heart failure in HORIZON-HF. The REVERSE study suggested that CRT improves ventricular function and reduces morbidity even in patients with few or no symptoms of heart failure and may delay or prevent worsening heart failure.