糖尿病大鼠肾脏细胞凋亡与Bax和Bcl-2基因表达

目的　观察糖尿病大鼠肾脏细胞凋亡、Bax和 Bcl- 2表达及二者的相关性。　方法　单侧肾切除大鼠腹腔注射链脲佐菌素诱发糖尿病 ,采用原位末端标记法检测肾脏细胞凋亡 ;流式细胞术和免疫组化检测肾皮质 Bax和 Bcl- 2表达水平 ;原位杂交检测 Bax和 Bcl- 2 m RNA表达 ,并观察尿蛋白、BU N、尿肌酐等反映肾功能的有关指标。　结果　在制模后 2、4、8、12周时 ,糖尿病组大鼠较对照组肾小球、肾小管凋亡细胞数明显增多 ,Bax、Bcl- 2蛋白和 m RNA的表达显著增强 (P<0 .0 5 )。随着大鼠糖尿病病程延长 ,肾功能恶化 ,肾脏凋亡细胞数逐渐增多 ,Bax表达亦逐渐增强 ,Bax/Bcl- 2比增加 ,且肾脏凋亡细胞数与 Bax及 Bax/Bcl- 2比具有相关性 (P<0 .0 5 )。　结论　肾脏凋亡细胞的不断增加可能是糖尿病肾病发生、发展的原因之一 ,Bax和 Bcl- 2可能参与肾脏细胞凋亡的调控。     

缬沙坦对2型糖尿病大鼠肾脏细胞凋亡及调控基因Bcl-2、Bax的影响

目的：观察缬沙坦对2型糖尿病大鼠肾脏细胞凋亡及其调控基因Bcl-2、Bax的影响。方法：随机选择15只SD雄性大鼠，以高糖高脂饲料喂养6周后，腹腔注射STZ30mg／kg；2周后血糖升高≥16mmol／L者12只，随机又分为2型糖尿病组（n=6）和2型糖尿病缬沙坦治疗组（简称治疗组，n=6），治疗8周，另选6只健康SD雄性大鼠为空白对照组，查内生肌酐清除率（Ccr），24h尿白蛋白的排泄率（Uaer）。流式细胞术检测大鼠肾脏细胞凋亡率。免疫组化法检测Bcl-2、Bax的表达。结果：8周后，糖尿病组大鼠肾小球细胞外基质增生，部分肾小管轻度萎缩或管腔扩张，上皮细胞肿胀，胞浆内可见脂肪空泡变性，但治疗组较糖尿病组病变减轻。细胞凋亡率糖尿病组较治疗组高（26．54±2．67VS20．05±2．03，P〈0．05）；Ccr糖尿病组较治疗组低（O．021±0．001VS0．065±0．004ml／min，P〈0．05），Uaer糖尿病组高于对照组和治疗组（O．150±0．004VS0．081±0．001，0．086±0．002mg，P〈0．05）。治疗组和糖尿病组肾小管均较对照组的Bcl-2和Bax阳性表达高（P-40．05），治疗组肾小管Bcl-2较糖尿病组的阳性表达高，而Bax阳性表达低（P〈O．05）。结论：缬沙坦通过增加Bcl-2／Bax在肾小管的比例，使糖尿病大鼠肾脏细胞凋亡率减低，保护肾功能。     

糖尿病大鼠组织非酶糖化、细胞凋亡与糖尿病肾病的关系

目的 探讨非酶糖化、凋亡相关蛋白Bcl-2和Bax与糖尿病肾病(DN)的关系.方法 雄性Wistar大鼠30只,随机平均分为3组,正常对照组、DN组、糖尿病氨基胍(10mg·kg<'-1>·d<'-1>)治疗组,腹腔注射链脲佐菌素(60 mg/kg)诱发糖尿病.16 w后,处死大鼠,分离肾脏,测定组织非酶糖化,观察Bcl-2、Bax的表达,取部分肾皮质电镜细胞计量、观察细胞凋亡的形态学变化.结果 ①与正常对照组相比,DN组肾脏皮质非酶糖化明显升高(P<0.001),氨基胍治疗组非酶糖化明显较DN组降低(P<0.01),而血糖无明显变化.②DN组肾脏Bcl-2蛋白表达减少、Bax蛋白表达增加,治疗组的Bcl-2蛋白表达较DN组增多,而Bax蛋白表达较DN组减少.③透射电镜下见DN组肾脏肾小管上皮细胞呈典型的凋亡形态学改变,治疗组大鼠肾组织细胞凋亡改变明显减轻.④DN组肾小球基底膜增厚,系膜区域扩大,治疗组病变减轻.结论 ①非酶糖化通过调节Bcl-2,Bax蛋白的表达诱导细胞凋亡,而参与DN的发生与发展.②非酶糖化抑制剂可调节Bax,Bcl-2的表达抑制细胞凋亡,明显改善糖尿病大鼠肾脏结构与功能,延缓DN的发展.     

甘草酸对糖尿病大鼠肾脏细胞凋亡的影响及防治糖尿病肾病的临床意义

雄性Wistar大鼠30只,随机平均分为3组,正常对照组、糖尿病组、糖尿病甘草酸（30mg／kg／d）治疗组,腹腔注射链脲佐菌素（60mg／kg）诱发糖尿病。16周后,处死大鼠,分离肾脏,观察Bcl-2、Bax的表达,取部允肾皮质电镜病理观察。结果①糖尿病组肾脏Bcl-2蛋白表达减少、Bax蛋白表达增加,甘草酸治疗组的Bcl-2蛋白表达较糖尿病组增多,而Bax蛋白表达较糖尿病组减少,电镜观察糖尿病组呈明显细胞凋亡形态学改变,甘草酸治疗组减轻。②糖尿病肾小球基底膜增厚,系膜区域扩大,甘草酸治疗组病变减轻。结论①糖尿病血糖升高可能调节Bcl-2、Bax蛋白的表达诱导细胞凋亡,而参与DN的发生与发展。②甘草酸可调查Bax、Bcl-2的表达抑制细胞凋亡,明显改善糖尿病大鼠肾脏结构与功能,延缓DN的发展。     

黄芩苷对糖尿病大鼠组织醛糖还原酶活性及肾脏细胞凋亡的影响

目的研究醛糖还原酶(AR)、凋亡相关蛋白Bcl-2和Bax与糖尿病肾病(DN)的关系,探讨醛糖还原酶抑制剂(ARIs)对DN的治疗作用。方法雄性Wistar大鼠40只,随机分为正常对照组、糖尿病组、依帕司他组、黄芩苷组,每组10只。除正常对照组外,其余各组大鼠腹腔注射STZ(60mg/kg),72h后建立糖尿病大鼠模型。依帕司他组灌胃依帕司他10mg.kg-1.d-1,黄芩苷组灌胃黄芩苷150mg.kg-1.d-1。16w后处死大鼠,测定晶体、肾脏组织AR活性,观察Bcl-2、Bax的表达,取部分肾皮质病理观察、电镜观察细胞凋亡的形态学变化。结果与正常对照组相比,糖尿病组晶体、肾脏皮质AR活性明显升高(P<0.001),两治疗组AR活性明显较糖尿病组降低(P<0.01),而血糖无明显变化。糖尿病组肾脏Bcl-2、Bax蛋白表达增加,治疗组的Bcl-2蛋白表达较糖尿病组增多,而Bax蛋白表达较糖尿病组减少。透射电镜下见糖尿病组肾脏肾小管上皮细胞呈典型的凋亡形态学改变,治疗组大鼠肾组织细胞凋亡改变明显减轻。糖尿病组肾小球基底膜增厚,系膜区域扩大,治疗组病变减轻。结论ARIs通过抑制AR活性,调节Bax、Bcl-2的表达抑制细胞凋亡,延缓DN的发展。黄芩苷对AR抑制作用与依帕司他相似。     

氯沙坦对糖尿病大鼠肾脏细胞凋亡及bax／bcl—2表达的影响

目的：探讨血管紧张素受体1拮抗剂（AT1Ra)对糖尿病肾脏细胞凋亡及凋亡相关基因的影响。方法：单侧肾切除大鼠腹腔注射STZ诱发糖尿病模型,每日灌胃给予AT1Ra氯沙坦（40mg/kg),共12周,采用原位末端标记法检测肾脏细胞凋亡情况,流式细胞术和免疫组化检测肾皮质Bax和Bcl-2表达,原位杂交检测bax和bcl-2 mRNA表达。结果：糖尿病组较对照组肾小球、肾小管凋亡细胞数明显增多,bax和bcl-2蛋白及mRNA表达增强,Bax/Bcl-2增高;氯沙坦治疗组较糖尿病组凋亡细胞数减少,bax表达减弱,bcl-2表达增强,Bax/Bcl-2降低。结论：氯沙坦可能通过影响凋亡相关基因bax和bcl-2表达而抑制肾脏细胞凋亡,从而发挥肾脏保护作用。     

福辛普利对慢性心力衰竭大鼠心肌细胞凋亡及相关基因表达的影响

目的:探讨福辛普利对慢性心力衰竭大鼠心肌细胞凋亡及相关基因表达的影响。方法:采用肾上腹主动脉缩窄法建立大鼠慢性心力衰竭模型,随机分为假手术组、慢性心力衰竭组、福辛普利组,每组10只大鼠。术后假手术组和慢性心力衰竭组给予生理盐水灌胃,福辛普利组给予福辛普利10 mg/(kg·d)灌胃。8周后,观察各组大鼠左心室舒张末压(LVEDP)、左心室内压最大上升及下降速率(±dp/dtmax)和左心室质量指数(LVMI);脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测大鼠左心室心肌细胞的凋亡指数(AI);SP免疫组织化学染色法检测左心室心肌组织B细胞白血病/淋巴瘤相关抗原2(Bcl-2)、B细胞白血病/淋巴瘤相关抗原相关X(Bax)蛋白的表达;蛋白免疫印记法(Western blotting)检测半胱氨酸天冬氨酸蛋白酶3(Caspase-3)蛋白的表达。结果:慢性心力衰竭组与假手术组相比,大鼠LVEDP、LVMI、心肌细胞凋亡指数、Bax蛋白、Caspase-3蛋白的表达均明显升高(P0.01),±dp/dtmax、Bcl-2蛋白的表达、Bcl-2/Bax比值显著下降(P0.01);与慢性心力衰竭组比较,福辛普利组大鼠LVEDP、LVMI、心肌细胞凋亡指数、Bax蛋白、Caspase-3蛋白的表达均明显降低(P0.01),±dp/dtmax、Bcl-2蛋白的表达、Bcl-2/Bax比值显著升高(P0.01),差异均有统计学意义。结论:慢性心力衰竭过程中发生了心肌细胞凋亡,福辛普利可通过上调Bcl-2的表达及下调Bax及Caspase-3的表达抑制心肌细胞凋亡,改善慢性心力衰竭大鼠心室功能及心肌肥厚。     

早期糖尿病大鼠视网膜神经细胞凋亡及胰岛素样生长因子Ⅰ的作用

早期糖尿病大鼠被随机分为正常组、糖尿病未治疗组，糖尿病胰岛素治疗组，糖尿病胰岛素样生长因子Ⅰ（ⅠGF—Ⅰ）治疗组，6周后处死大鼠，用原位末端标记法（TUNEL法）标记大鼠视网膜凋亡细胞，免疫组化法观察Bcl-2、Bax蛋白表达。结果表明ⅠGF—Ⅰ可增加Bcl-2表达、减少Bax表达，抑制视网膜神经细胞凋亡。     

丝胶对2型糖尿病大鼠胰岛细胞凋亡的保护作用

目的观察丝胶对2型糖尿病大鼠胰岛细胞凋亡的保护作用。方法雄性SD大鼠36随机分为3组:正常对照组、糖尿病模型组和丝胶治疗组。链脲佐菌素(STZ,25 mg/kg,连续3 d)腹腔注射建立2型糖尿病大鼠模型;待模型成功建立后,丝胶治疗组大鼠给予丝胶灌胃(2.4 g.kg-1.d-1)35 d。免疫组织化学染色观察胰岛β细胞Bcl-2和Bax蛋白的表达。结果与正常对照组大鼠相比,模型组大鼠胰岛β细胞Bax蛋白的表达明显升高(P<0.01),Bcl-2蛋白的表达明显降低(P<0.01);与模型大鼠相比,丝胶治疗组大鼠胰岛β细胞Bax蛋白的表达明显降低(P<0.01),Bcl-2蛋白的表达明显升高(P<0.01)。结论丝胶可通过上调胰岛β细胞Bcl-2蛋白的表达、下调胰岛β细胞Bax蛋白的表达,抑制2型糖尿病大鼠胰岛细胞凋亡,对糖尿病时胰岛细胞损伤具有一定的保护作用。     

牛蒡颗粒剂对糖尿病大鼠氧化应激、细胞凋亡的影响及糖尿病心肌病变的防治

目的探讨中药牛蒡对氧化应激和心肌细胞凋亡的影响及对糖尿病大鼠的心肌保护作用和机制。方法雄性Wistar大鼠30只,腹腔内注射链脲佐菌素(60 mg/kg)制备糖尿病大鼠模型,随机平均分为三组,正常对照组、糖尿病组、牛蒡(150 mg·kg-1·d-1)治疗组。切取大鼠心肌组织,检测超氧化物歧化酶(SOD)活性水平变化及丙二醛(MDA)含量,观察心肌细胞凋亡相关蛋白Bcl-2和Bax的表达。取部分心肌组织光镜及电镜下观察细胞凋亡形态学改变。结果①糖尿病组大鼠心肌组织MDA含量均明显增高(P<0.01),SOD活性水平明显降低(P<0.01);牛蒡治疗组较糖尿病组MDA含量降低(P=0.000),SOD活性水平升高(P=0.000)。②糖尿病组Bcl-2蛋白表达减少、Bax蛋白表达增加;与糖尿病组相比,牛蒡治疗组的Bcl-2蛋白表达增多,而Bax蛋白表达减少。③光镜下可见糖尿病组心肌细胞排列紊乱、肿胀,牛蒡治疗组病变减轻。④透射电镜下见糖尿病组心肌细胞呈典型的凋亡形态学改变,牛蒡治疗组心肌细胞凋亡明显减轻。结论氧化应激及细胞凋亡参与了糖尿病心肌病变的发生发展。中药牛蒡对糖尿病大鼠心肌病变具有明显防治作用。改善氧化应激,调节Bcl-2,Bax蛋白的表达而抑制心肌细胞凋亡,可能是牛蒡发挥心肌保护作用的机制之一。     

妊娠时间与肺结核复发的相关性研究及诊治对策

目的 分析肺结核史患者妊娠时间和肺结核复发间相关性.方法 选取我院收治的有肺结核史的妊娠妇女576例作为研究对象,对其妊娠前肺结核治疗、治愈后妊娠时间、妊娠后复发肺结核等进行分析,总结有肺结核史育龄女性的妊娠时间和肺结核复发之间的关系.结果 肺结核治愈后不同时间段妊娠者的结核复发率比较,差异具有显著性（P＜0.05）,停药后间隔时间越久妊娠,肺结核复发的几率越小.结论 加强孕期痰菌检查,及早发现复发肺结核,提高母婴安全.     

我国骨关节结核诊治的回顾与展望

骨关节结核是危害人们健康的严重感染性疾病,近95％由他处结核病继发而来.罹患骨关节结核疾病后几乎均将致残,严重影响人们的健康、工作和生活.建国以来在党和国家的关心和支持下,骨关节结核的诊治水平取得了长足进步.时至今日,由于多种原因,学科发展和被重视程度受到一定的制约,同整个医疗行业的发展不相适应.回顾过去,展望未来,我们需要重新审视骨关节结核的诊治方法,努力推进骨关节结核诊疗技术的科学发展.     

Effect of phosphorylation of MAPK and Stat3 and expression of c-fos and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44~(MAPK), p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44~(MAPK), p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44~(MAPK) and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between P42/44~(MAPK) and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Raf/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44~(MAPK), c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

Overweight and Obesity and Progression of ADPKD

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Effect of phosphorylation of MAPK and Stat3 and expression of c-fas and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44MAPK, p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44MAPK, p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44MAPK and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between p42/44MAPK and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Rat/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44MAPK, c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice

Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology.     

Replication and Inhibitors of Enteroviruses and Parechoviruses

The Enterovirus (EV) and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV). They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.     

荣宝和氯硝柳胺灭螺效果比较及成本分析

目的 评价新型灭螺药物荣宝杀灭钉螺的效果,探讨其推广应用价值.方法 按目前推荐的荣宝灭螺剂量,喷洒法为30 g/m2,浸杀法为50 g/m3;氯硝柳胺喷洒法和浸杀法分别采用2 g/m2和2 g/m3杀螺剂量,分别在室内和现场进行灭螺试验,观察两种药物的灭螺效果并初步分析评估其成本.结果 在现场气温22～30℃条件下,荣宝50 g/m3浸杀3、5、7 d后,螺袋内钉螺校正死亡率均达到100.0%,与氯硝柳胺2 g/m3灭螺效果相似;荣宝30 g/m2剂量喷洒3、5、7、15 d后,钉螺校正死亡率分别为54.5%、58.0%、69.0%、79.1%,氯硝柳胺喷洒组钉螺校正死亡率分别为61.0%、69.4%、76.7%、77.9%.在室温18℃条件下,荣宝以30 g/m2喷洒3、5、7、15 d后,钉螺校正死亡率分别为72.9%、87.2%、91.5%、76.1%;而相应2 g/m2氯硝柳胺喷洒后的钉螺校正死亡率分别为81.3%、95.7%、97.9%、80.4%.同样完成1000 m2的喷洒灭螺任务,荣宝所需灭螺药物和人力资费成本比氯硝柳胺多支出0.114元/m2;完成72 m3的浸杀灭螺任务,荣宝所需灭螺药物和人力资费成本比氯硝柳胺多支出0.127元/m3.50 g/m3荣宝浸杀灭螺剂量,对成鱼(＞250 g)的活力不会造成影响,但对鱼类幼苗仍具较强毒性.结论 荣宝与氯硝柳胺灭螺效果相似,由于其成本较高,氯硝柳胺仍然是目前首选灭螺药物,但荣宝的鱼类毒性低,可作为氯硝柳胺之外有益的补充灭螺药物.     

心电图、心电向量图与冠状动脉造影结果对比分析

目的:通过分析心电图(Electrocardiogram,ECG)和心电向量图(Vectorcardiogram,VCG)的改变与冠脉造影（CAG）结果进行对比,探讨ECG、VCG在冠状动脉病变中的诊断价值。方法: 选择2008年1月~2009年12月临床拟诊断为冠心病患者108例,行常规ECG、VCG检查,并于1周内进行CAG,对检查结果依据各自的诊断标准进行判定,以CAG为标准诊断法,利用四格表法,计算相关评价真实性的指标并进行比较。结果: ①VCG检测的灵敏度、特异度、准确度显著高于ECG(P<0.05,P<0．01)。②ECG、VCG阳性率与冠脉病变支数组间比较:在单支病变、双支病变中,VCG阳性率明显高于ECG(P<0.05),左主干或三支病变无统计学意义;组内比较:ECG组左主干或三支病变组较单支病变、双支病变阳性率高(P<0.05,P<0.01);VCG组左主干或三支病变组较单支病变阳性率高(P<0.05);与双支病变阳性率比较无统计学意义;③ECG、VCG阳性率与冠脉病变程度组间比较:冠脉病变狭窄50%～69%的VCG阳性率明显高于ECG (P<0.05),其他两组阳性率比较无统计学意义;组内比较:ECG组冠脉病变狭窄≥90%较50%～69%、70%～89%的阳性率高(P<0.05,P<0.01); VCG组狭窄≥90%较50%～69%阳性率高（P<0.01),其他无统计学意义。结论: VCG对冠心病检测价值显著高于ECG。     

Detection and characterization of the product of hydroethidine and intracellular superoxide by HPLC and limitations of fluorescence

Here we report the structural characterization of the product formed from the reaction between hydroethidine (HE) and superoxide (O(2)(.-)). By using mass spectral and NMR techniques, the chemical structure of this product was determined as 2-hydroxyethidium (2-OH-E(+)). By using an authentic standard, we developed an HPLC approach to detect and quantitate the reaction product of HE and O(2)(.-) formed in bovine aortic endothelial cells after treatment with menadione or antimycin A to induce intracellular reactive oxygen species. Concomitantly, we used a spin trap, 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide (BMPO), to detect and identify the structure of reactive oxygen species formed. BMPO trapped the O(2)(.-) that formed extracellularly and was detected as the BMPO-OH adduct during use of the EPR technique. BMPO, being cell-permeable, inhibited the intracellular formation of 2-OH-E(+). However, the intracellular BMPO spin adduct was not detected. The definitive characterization of the reaction product of O(2)(.-) with HE described here forms the basis of an unambiguous assay for intracellular detection and quantitation of O(2)(.-). Analysis of the fluorescence characteristics of ethidium (E(+)) and 2-OH-E(+) strongly suggests that the currently available fluorescence methodology is not suitable for quantitating intracellular O(2)(.-). We conclude that the HPLC/fluorescence assay using HE as a probe is more suitable [corrected] for detecting intracellular O(2)(.-).