急性呼吸窘迫综合征时足三里穴及相关脏腑 组织氧分压变化的实验研究

目的 观察急性呼吸窘迫综合征(ARDS)时经穴组织及相关脏腑组织氧分压变化的特点,阐明ARDS局部组织氧合情况与全身氧合情况的相关性及经穴组织和相关脏腑氧代谢的相关性.方法 选择健康新西兰大白兔20只,按随机数字表法分为ARDS模型组和对照组,每组10只.采用颈静脉注射油酸(0.08~ 0.1 mL/kg)的方法复制ARDS动物模型;对照组仅行气管切开、机械通气、动/静脉置管等操作而不给予油酸.用组织氧测定仪测定吸入氧浓度(FiO2)分别为0.21和1.00时两组足三里穴内、胃和肝组织的氧分压(PtO2),同时行动脉血和混合静脉血血气分析,计算氧摄取率(O2ER).结果 FiO2 0.21时ARDS模型组足三里穴内、胃和肝PtO2均明显高于对照组,动脉血氧分压(PaO2)、混合静脉血氧分压(PvO2)、动脉血氧饱和度(SaO2)、混合静脉血氧饱和度(SvO2)、O2ER均明显低于同期对照组.FiO2 1.00时两组足三里穴内、胃和肝PtO2及PaO2、SaO2、O2ER均较FiO2 0.21时升高,以ARDS模型组足三里穴内、胃和肝PtO2、O2ER水平升高更显著〔PtO2(kPa):足三里穴内:16.75±2.12比13.80±1.83,胃:16.45±1.33比13.35±1.25,肝:16.43±1.45比13.45±1.36, O2ER:(36.14±0.97)%比(30.81±1.01)%〕,PaO2、SaO2、SvO2以对照组升高更显著〔PaO2(mmHg,1 mmHg= 0.133 kPa):682.02±50.32比159.32±40.17,SaO2:1.00±0.00比0.98±0.01,SvO2:0.69±0.01比0.63±0.03,均P<0.05〕.与本组FiO2 0.21时比较,ARDS模型组FiO2 1.00时PvO2升高,对照组则降低,ARDS模型组和对照组比较差异有统计学意义(mmHg:36.00±2.83比42.50±1.70,P<0.05).且足三里穴内和胃PtO2呈正相关(r=0.963,P<0.001).结论 ARDS时在全身性氧输送障碍情况下,脏腑组织氧需求显著增加,但氧利用明显障碍,这可能与细胞线粒体功能障碍有关.经穴组织与相关脏腑组织氧分压有很好的相关性,经穴组织氧测定对脏腑组织氧代谢监测有重要的指导意义.     

血清肌钙蛋白I在急性有机磷农药中毒心肌损伤诊断中的价值

目的：探讨测定血清肌钙蛋白I（ cTnI）对急性有机磷农药中毒（ AOPP）患者心肌损伤诊断的价值及临床意义。方法AOPP患者98例,分别于中毒第1 d、第2 d、第3 d、第5 d、第7 d,测定血清cTnI、肌酸激酶（ CK）、肌酸激酶同工酶（ CK－MB）、乳酸脱氢酶（ LDH）的值,观察峰值出现规律。按中毒的严重程度将其分为轻度中毒组、中度中毒组、重度中毒组。选取在本院体检的25例健康者作为对照组。将各组中毒患者各指标检查结果与对照组进行比较。结果 AOPP患者血清cTnI在中毒第2 d达高峰,第7 d仍显著高于对照组（ P＜0.01）,CK、CK－MB、LDH于中毒后第3 d达高峰;不同程度中毒患者血清cTnI 和心肌酶谱值随着病情的严重增加而增高,但cTnI增幅比CK、CK－MB、LDH更大。结论 AOPP越严重,血清cTnI值升高越明显,血清cTnI测定有助于对AOPP心肌损害的早期诊断,在抢救AOPP患者时,有必要对患者血清cTnI和心肌酶谱值进行动态观察,尤其是血清cTnI 的变化,其对AOPP心肌损伤的诊断比心肌酶谱有更高敏感性,更有价值。     

轮状病毒感染性脓毒症患儿血清CRP、免疫球蛋白水平变化及其与心肌酶谱的相关性研究

目的：分析轮状病毒感染性脓毒症患儿血清CRP、免疫球蛋白水平变化及其与心肌酶谱的关系。方法选择在本院接受住院治疗的56例轮状病毒感染性脓毒症患儿作为观察组,选择同期在本院注射疫苗的56例健康小儿作为对照组,比较两组研究对象的血清CRP、免疫球蛋白水平及心肌酶谱指标值差异,分析血清CRP、免疫球蛋白水平与心肌酶谱相关性。结果(1)观察组患儿血清CRP水平显著高于对照组(P<0.05),但其血清IgG、IgM、IgA等免疫球蛋白水平均显著低于对照组(P<0.05);(2)观察组患儿的血清高敏心肌肌钙蛋白(hs-cTnT)、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)等心肌酶谱指标值明显高于对照组(P<0.05);(3)血清CRP水平与hs-cTnT、CK、CK-MB呈正相关(P<0.05),IgG、IgM、IgA水平与hs-cTnT、CK、CK-MB呈负相关(P<0.05)。结论轮状病毒感染性脓毒症患儿血清CRP、心肌酶谱水平升高,免疫球蛋白水平降低,且心肌酶谱指标值与血清CRP、免疫球蛋白含量具有相关性。     

单纯性心肌桥-壁冠状动脉的双源CT表现与心肌缺血的相关性研究

目的：探讨双源CT在检查单纯性心肌桥-壁冠状动脉(MB-MCA)的临床价值,并讨论单纯性MB-MCA与心肌缺血之间的关系。方法回顾双源CT冠脉成像检出的239例单纯性MB-MCA的临床资料。结果双源CT冠脉成像发现239例单纯性MB-MCA患者中90.16%位于左前降支。其中静息心电图提示心肌缺血者的有50例,24 h动态心电图检查有心肌缺血者19例,其余170例无心电图变化。分析两组检测指标发现, MB厚度、MCA横断面面积及狭窄程度比较差异具有统计学意义(P<0.05),而MCA长度比较则差异无统计学意义(P>0.05)。结论双源CT冠脉成像可用于单纯性MB-MCA的诊断,结合心电图及临床相关资料,有助于单纯性心肌桥引起心肌缺血的诊断。     

PI3K/AKT/GSK-3β信号通路与心肌缺血/再灌注损伤的相关性研究

磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/AKT)信号通路在肿瘤细胞中被发现。随着分子医学的发展,研究发现,该通路通过调控下游的多种效应分子对器官的缺血/再灌注损伤起保护作用,其中糖原合成酶激酶3β(GSK-3β)是主要效应分子,两者联合被称为PI3K/AKT/GSK-3β信号通路。该通路在心肌细胞缺血/缺氧培养、心肌暖缺血/再灌注损伤及离体心脏心肌缺血/再灌注损伤中的保护作用已经得到证实,但在心脏移植中对于心肌缺血冷保护及移植后的再灌注损伤的作用报道较少,需要进一步探讨。     

丹红注射液对脓毒症大鼠心肌组织氧自由基及HMGB1表达的影响

目的观察丹红注射液对脓毒症大鼠心肌损伤的保护作用,探讨其可能作用机制。方法24只雄性Wistar大鼠随机分为正常组、假手术组、模型组、丹红组,每组6只。盲肠结扎并穿孔(CLP)法建立脓毒症大鼠动物模型,观察各组心肌组织超微结构改变,心肌组织丙二醛(MDA)、超氧化物岐化酶(SOD)和高迁移率族蛋白1(HMGB1)含量的变化。结果 CLP术后24h,与手术组比较,模型组、丹红组大鼠心肌组织MDA含量[(5.5706±1.3251)μ/mg prot、(3.9900±1.0559)μ/mg prot比(1.1506±0.1771)μ/mg prot]、HMGB1蛋白表达量(0.6074±0.0504、0.5010±0.1049比0.1427±0.0345)升高,差异有统计学意义(P0.05),而模型组、丹红组大鼠心肌组织SOD活力[(10.5276±3.0568)nmol/mg prot、(15.5129±3.4425)nmol/mg prot比(20.5604±3.1312)nmol/mg prot]降低,差异有统计学意义(P0.05);与模型组比较,丹红组大鼠心肌组织MDA含量表达降低[(3.9900±1.0559)μ/mg prot比(5.5706±1.3251)μ/mg prot,P0.05],SOD活力升高[(15.5129±3.4425)nmol/mg prot比(10.5276±3.0568)nmol/mg prot,P0.05],心肌组织HMGB1表达量降低(0.5010±0.1049比0.6074±0.0504,P0.05);相同时间点心肌超微结构提示模型组大鼠心肌细胞线粒体肿胀,部分空泡变性;丹红组心肌细胞损伤轻于模型组。结论丹红注射液对脓毒症大鼠心肌损伤有一定程度的保护作用,其作用机制可能与清除氧自由基,降低HMGB1含量有关。     

High Recovery of Functional Islets Stored at Low and Ultralow Temperatures

BACKGROUND: Poor recovery of islets upon cryopreservation is the main hurdle in islet banking. Pancreatic islets have a poor antioxidative defense mechanism, and exposure of islets to low temperature leads to oxidative stress. AIM: We aimed to investigate whether known compounds such as metformin, γ aminobutyric acid (GABA), docosahexanoic acid (DHA), or eicosapentaenoic acid (EPA) alone or in combination are capable of reducing oxidative stress for better islet recovery upon storage at suboptimal temperatures. METHODS: Islets isolated from mouse pancreas were stored at low temperature (4°C) for 15 days and at ultralow temperature (-196°C) for 30 days with or without additives. After revival from cold storage, islets were assessed by using three methods: (1) specificity by dithizone (DTZ), (2) viability by fluorescein diacetate/propidium iodide (FDA/PI) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zolium bromide (MTT) assay, and (3) functionality by glucose-stimulated insulin secretion (GSIS). The oxidative status of the islets stored at suboptimal temperatures was determined by both intracellular free radical release (fluorometric analysis) and lipid peroxidation (enzymatic determination). RESULTS: Supplementation with additives led to an improvement in islet survival upon storage at suboptimal temperatures, without depletion of insulin secretory activity, which was comparable to that of controls. The additives acted as cryoprotectants and antioxidants as revealed by high recovery of viable islets and reduction in total reactive oxygen species (ROS) and malonidealdehyde (MDA), respectively. CONCLUSIONS: Our results demonstrate for the first time that supplementation with EPA, DHA, and metformin may lead to higher islet recovery from -196°C storage, enabling proper islet banking.     

Development and course of heart failure after a myocardial infarction in younger and older people

Background Acute myocardial infarction （AMI） is a common cause of heart failure （HF）, which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 （8%）, 68 （23%） and 107 （37%） oc- curred during the index admission, many associated with acute HF. A further 37 （12%）, 63 （21%） and 82 （29%） developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 （24%）, 55 （40%） and 37 （47%） patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 （70%）, 93 （91%） and 107 （85%） in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF.