Freshwater clam extract decreased hemorrhagic shock-induced liver injury by attenuating TNF-α production

Freshwater clam (Corbicula fluminea), a popular edible shellfish in Asia, is said to have beneficial effects on liver function. However, scientific evidence for such benefit is limited. In this study, the authors aimed to assess the treatment effects of freshwater clam extract (FCE) administration after hemorrhagic shock (HS) in rats. The authors randomly divided animals into three groups. After inducing HS in rats in the HS + FCE (n = 12) and HS groups, the authors fed 20 mg/kg FCE orally to rats in the HS group only. The authors neither induced HS in nor fed FCE to rats (n = 8) in the vehicle group. The authors measured the blood levels of white blood cells (WBC), aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and tumor necrosis factor-alpha (TNF-α) at several time points during the experiment. After 48 hr, the authors sacrificed the rats and harvested the livers for hematoxylin and eosin (HE) staining. The HS significantly decreased mean arterial pressure (MAP), increased blood AST, ALT, and LDH levels and induced liver injury in rats. Treatment with FCE increased MAP level and decreased AST, ALT, LDH, and TNF-α levels after hemorrhage. The HE staining showed diminished organ injury in the FCE-treated group. In conclusion, the administration of posttreatment FCE suppressed the release of pro-inflammatory TNF-α production after HS and decreased the levels of markers of liver injury associated with HS in rats. These beneficial effects suggest that FCE is a potential immunomodulator.     

Influence of rutin treatment on biochemical alterations in experimental diabetes

Dietary antioxidant compounds such as flavonoids may offer some protection against early-stage diabetes mellitus and its complications. Abnormalities in both glucose metabolism and lipid profile constitute one of the most common complications in diabetes mellitus. The present study aimed to evaluate the effect of rutin, through biochemical parameters, on experimental streptozotocin (STZ)-induced diabetes in rats. Male Wistar rats were divided into four groups: untreated controls (GI); normal rats receiving rutin (GII); untreated diabetics (GIII); diabetic rats receiving rutin (GIV). STZ was injected at a single dose of 60 mg kg^-1 to induce diabetes mellitus. The diabetes resulted in increased serum glucose, cholesterol, triacylglycerols and lipoproteins (LDL and VLDL-cholesterol) but decresed serum HDL-cholesterol and insulin. Rutin (50 mg kg^–1) reduced (p < 0.05) blood glucose and improved the lipid profile in STZ-induced diabetic rats. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) activities were significantly augmented in serum of STZ-diabetic rats, while these activities were diminished in hepatic and cardiac tissues compared with the control group. Rutin prevents changes in the activities of ALT, AST and LDH in the serum, liver and heart, indicating the protective effect of rutin against the hepatic and cardiac toxicity caused by STZ. Rutin was associated with markedly decreased hepatic and cardiac levels of tryacylglycerols and elevated glycogen. These results suggest that rutin can improve hyperglycemia and dyslipidemia while inhibiting the progression of liver and heart dysfunction in STZ-induced diabetic rats.     

复方片仔癀肝宝对酒精诱导的慢性肝损伤氧化应激的保护作用研究

目的:探讨复方片仔癀肝宝对酒精性肝病(Aleoholie Liver Disease,ALD)模型大鼠氧化应激的保护作用。方法:60只SPF级SD大鼠,随机分为正常对照组、模型组、阳性药对照组及肝宝低、中、高剂量组,每组10只。除正常对照组外其余各组用酒精联合高脂饲料喂养2周,造ALD模型,连续给药4周后取材。全自动生化仪检测血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、碱性磷酸酶(ALP)、乳酸脱氢酶(LDH)的含量变化;检测肝组织中超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-Px)的表达;HE染色,观察肝组织病理变化。结果 :模型组血清中ALT、AST、ALP、LDH的活性较正常对照组均有明显的上升,且肝组织中MDA水平明显上升,SOD、GSH-Px水平明显下降(P0.01)。与模型组相比,肝宝各组ALT、AST、ALP、LDH的活性及MDA水平明显降低,而SOD、GSH-Px水平明显上升(P0.05)。HE染色结果显示复方片仔癀肝宝不同剂量组对肝组织脂肪变性、肝内脂类聚集有明显的改善作用,并且存在剂量效应关系。结论:复方片仔癀肝宝能显著减轻酒精和高脂诱导的肝损伤,其机制可能与提高肝组织的抗氧化能力有关。     

参麦与葛根素注射液联合应用对肝缺血再灌注早期损伤的影响

目的：探讨参麦、葛根素注射液联合应用对大鼠肝缺血再灌注早期损伤的影响。方法：SD雄性大鼠50只,复制肝缺血再灌注损伤模型。随机分为：假手术组,模型组,参麦注射液干预组（5mL／kg）,葛根素注射液干预组（35mg／kg）及参麦、葛根素注射液联合应用干预组（3mL／kg和25mg／kg）,每组10只。于再灌注后1h检测肝组织丙二醛（MDA）含量及血清谷丙转氨酶（ALT）、谷草转氨酶（AST）和乳酸脱氢酶（LDH）的含量;光镜下比较各组肝组织形态学的变化。结果：模型组血清ALT,AST,LDH含量及肝组织MDA含量均明显高于假手术组（P〈0．05）;参麦、葛根素注射液干预组及二者联合应用干预组血清ALT,AST,LDH及肝组织MDA含量均低于模型组（尸〈0．05）;参麦、葛根素注射液联合应用组血清ALT,AST,LDH及肝组织MDA含量的下降程度仅较单独使用二者时稍低,组问差异不明显,无统计学意义（P〉0．05）;光镜下参麦、葛根素注射液干预组及联合应用干预组的肝细胞损伤程度均较模型组明显减轻,但二者联合应用干预组的肝细胞损伤程度并未较单独使用二者时明显改善。结论：参麦、葛根素注射液对肝缺血再灌注损伤具有一定的保护作用,但二者联合应用不能进一步改善肝缺血再灌注所致的早期损伤。     

蛋白酶抑制剂对肝缺血-再灌注损伤的保护作用

目的：探讨蛋白酶抑制剂及中性粒细胞在肝缺血－再灌注损伤中的作用。方法：采用大鼠部分肝缺血－再灌注模型，将健康雄性SD大鼠32只随机分为4组，手术对照组（A组），肝缺血90分钟组（B组），肝缺血90分钟，再灌注120分钟组（C组），肝缺血90分钟，再灌注120分钟加缺血前30分钟静注乌司他丁组（D组），观察动物肝组织病理切片；分别测定血浆中天冬氨酸转氨酶（AST），丙氨酸转氨酶（ALT），乳酸脱氢酶（LDH）浓度，测定肝组织中髓过氧化物酶（MPO）含量，结果：光镜下B，C2组与A组比较，肝小叶结构紊乱，肝血窦和中央静脉有程度不同的淤血，有的肝血窦变窄，内皮细胞及肝细胞普遍水肿变性；C组肝细胞坏死较B组明显；D组上述改变明显减轻，血浆中肝功能酶学指标显著升高（B，C组与A组比较，P均＜0．05），肝组织中MPO活性升高，以再灌注120分钟组为著（C组与A组比较，P＜0．01），D组血浆中ALT，AST，LDH和MPO含量均较C组明显下降，结论：肝缺血－再灌注时，聚集，黏附在肝组织中的大量中性粒细胞通过释放蛋白酶造成肝损伤，蛋白酶抑制剂乌司他丁能明显减轻这种损伤，保护肝功能。     

乌司他丁对大鼠肝缺血-再灌流损伤的保护作用

目的研究乌司他丁对肝缺血再灌流损伤的保护作用。方法将45只成年雄性SD大鼠随机分成3组:假手术对照组(A组)、肝缺血30min、再灌流90min组(B组)、缺血前30min静脉注射乌司他丁+肝缺血30min、再灌流90min组(C组)。分别测血浆中天冬氨酸转氨酶(AST)、丙氨酸转氨酶(ALT)、乳酸脱氨酶(LDH)浓度;测定肝组织中髓过氧化物酶(MPO)含量,并取肝组织作光镜及电镜观察。结果再灌流90min时C组的血浆ALT、AST、LDH值及肝组织MPO含量均低于B组(P<0.01),且C组的肝细胞显微、超微结构损害的改变较B组的轻。结论乌司他丁能抑制肝缺血再灌流时中性粒细胞在肝组织中的聚集,从而对大鼠肝缺血再灌流所致肝细胞的结构和功能损伤有保护作用。     

哌唑嗪抑制脂多糖诱导的磷脂酶A2活性 及肝细胞内钙离子超载

目的：研究α－肾上腺素受体拮抗剂哌唑嗪对脂多糖（LPS）诱导的大鼠血清中磷脂酶A2活性及肝细胞内钙离子浓度[Ca^2 ]i超载的抑制及其对内毒素性肝损害的保护作用及机制。方法：用腹腔注射LPS（2mg/kg)复制急性肝损害型，用哌唑嗪（4mg/kg)灌胃为保护组；检测了处置6小时后各组大鼠肝细胞内[Ca^2 ]i，24小时后血清丙氨酸转氨酸转氨酶、天冬氨酸转氨酶、乳酸脱氨酶、γ－谷氨酰转肽酶及肝脏病理切片；并对各组血清中分泌型磷脂酶A2（sPLA2)活性，前列腺素E2（PGE2）肿瘤坏死因子－α（TNF-α）的含量进行了动态测定。结果：哌唑嗪明显降低了由LPS诱导的肝细胞[Ca^2 ]i升高和肝功能损害，减轻了肝细胞坏死程度和炎性浸润，同时对LPS所引起的血清中sPLA2,PGE2和TNF－α的升高均有不同程度的抑制。结论：哌唑嗪可通过降低LPS诱导的肝细胞内Ca^2 超载、减少TNF－α的产生从而抑制sPLA的过度激活及炎症介质的产生，对肝脏具有明显的保护作用。     

盐酸戊乙奎醚对大鼠肝脏缺血再灌注损伤的保护作用

【目的】探讨盐酸戊乙奎醚对大鼠肝脏缺血再灌注损伤的影响及作用机制。【方法】通过大鼠肝脏缺血再灌注损伤模型,检测大鼠血清丙氨酸氨基转移酶（ALT）和天冬氨基酸转移酶（AST）,肝组织匀浆丙二醛（MDA）的变化。观察光镜下肝脏病理形态改变。【结果】经盐酸戊乙奎醚处理的C组血清ALTAST和MDA的浓度明显低于B组（对照组）而高于A组（假手手术组）;C组光镜下肝脏病理形态改变较B组轻微。【结论】盐酸戊乙奎醚对大鼠肝脏缺血再灌注损伤有保护作用。     

加贝酯对大鼠肝脏缺血再灌注损伤细胞因子的作用和影响

【目的】观察细胞因子在大鼠肝脏缺血再灌注损伤中的变化和加贝酯（GM）对其的作用、影响及可能的机制。【方法】采用Pringle＇s法建立大鼠肝脏缺血再灌注模型,将40只SD大鼠随机分成四组,每组10只：A组（手术对照组）、B组（缺血再灌注组）、C组（加贝酯处理组）、D组（盐水对照组）。光镜观察肝脏病理组织学变化,测定血清中天冬氨酸氨基转移酶（AST）、丙氨酸氨基转移酶（ALT）、肿瘤坏死因子－α（TNF-α）及白介素6（IL－6）的含量。【结果】肝脏缺血再灌注损伤时,AST、ALT、TNF-α、IL－6含量显著地升高,并出现明显的病理学改变;而加贝酯处理后上述改变均明显减轻,其差异有显著性（P〈0．05）。【结论】肝缺血再灌注损伤后,产生大量的炎性细胞因子,而加贝酯通过其细胞保护作用、减少炎性细胞因子的产生及减轻炎症反应而产生肝保护作用。     

Coexposure of lead- and lipopolysaccharide-induced liver injury in rats: involvement of nitric oxide-initiated oxidative stress and TNF-alpha

In this study, we investigated the interaction between lipopolysaccharide (LPS) and lead (Pb) and the involvement of tumor necrosis factor-alpha (TNF-alpha) and oxidative stress in Pb-plus-LPS (Pb/LPS)-induced liver damage in rats. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), TNF-alpha, nitric oxide (NO), and lipid peroxidation (LPO) were determined in rats treated with Pb and/or LPS. Pb ranging from 0 to 15 mg/kg dose dependently increased AST, ALT, NO, or LPO in LPS-treated rats. Pretreatment with iNOS inhibitor 1400W reduced NO, LPO, TNF-alpha, AST, and ALT in Pb/LPS-treated rats. Thus, Pb increased LPS-induced liver damage, which might be associated with increased NO-initiated oxidative stress and TNF-alpha in rats.     

芍药苷预处理对肝缺血再灌注大鼠肝功能及线粒体损伤的影响

目的探讨芍药苷预处理对肝缺血再灌注大鼠肝功能及线粒体损伤的影响。方法健康雄性SD大鼠64只,按照随机区组设计法分为假手术组(S组)、肝缺血再灌注组(I-R组)、芍药苷组(PF组)和生理盐水组(NS组),每组16只。I-R组、PF组和NS组采用肝脏缺血60min进行再灌注的方法制备70%肝脏缺血再灌注损伤模型。PF组于模型制备前7d通过尾静脉连续注射芍药苷30mg/(kg·d),共7d;NS组于模型制备前7d通过尾静脉连续注射0.9%Nacl注射液30mg/(kg·d),共7d。于再灌注6h后经心脏采集血液标本测定血清丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)水平;取肝组织测定肝细胞凋亡情况,计算肝细胞凋亡指数(AI);制备肝细胞单细胞悬液,测定线粒体膜电位(△Ψm);提取肝组织线粒体,测定线粒体三态呼吸速率和四态呼吸速率(氧浓度降低值/实际时间),计算呼吸控制率(三态呼吸速率/四态呼吸速率)和磷氧比。结果与S组比较,I-R组和PF组大鼠AI、ALT、AST和四态呼吸速率水平明显升高,三态呼吸速率、呼吸控制率、磷氧比和△Ψm水平明显降低,差异有统计学意义(P<0.05);与I-R组比较,PF组大鼠AI、ALT、AST和四态呼吸速率水平明显降低,三态呼吸速率、呼吸控制率、磷氧比和△Ψm水平明显升高,差异有统计学意义(P<0.05)。结论芍药苷预处理可减轻大鼠肝缺血再灌注损伤,其机制可能与保护线粒体有关。     

聚合人脐带血血红蛋白预处理对肝缺血/再灌注损伤的保护作用

目的探讨聚合人脐带血血红蛋白(PolyPHb)预处理对SD大鼠肝脏缺血/再灌注(I/R)损伤的保护作用。方法采用随机分组对照研究的方法,将30只成年雄性SD大鼠平均分为假手术(Sham)组、I/R组和PolyPHb预处理(PolyPHb)组;采用大鼠70%肝I/R损伤模型,缺血前I/R组和PolyPHb组动物分别静脉推注生理盐水和PolyPHb(0.3 gHb/kg)预处理,然后缺血60 min,再灌注3 h。检测术前及术后丙氨酸转氨酶(ALT)和谷草转氨酶(AST)活性,并采集术后肝脏组织标本行HE染色和TUNEL染色。结果 PolyPHb组、I/R组的肝酶释放ALT、AST分别为(350.9±80.8)U/L vs(830.5±85.7)U/L(P<0.01)和(446.1±97.10)U/L vs(1 096.2±135.6)U/L(P<0.01),肝细胞凋亡发生率分别为(15.62±8.58)%vs(35.21±9.62)%(P<0.01)。结论 PolyPHb预处理对大鼠肝脏I/R损伤具有明显的保护作用。     

A descriptive analysis of aspartate and alanine aminotransferase rise and fall following acetaminophen overdose

Context: Risk prediction following acetaminophen (paracetamol, APAP) overdose is based on serum APAP, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels. One recently proposed risk stratification tool, the APAPxAT multiplication product, uses either AST or ALT, whichever is higher, yet their interrelation is not well known following APAP-induced hepatic injury. Objective: To describe the kinetics of AST and ALT release into and disappearance from the circulation following APAP overdose. Materials and Methods: An observational case series of adult patients with peak AST or ALT > 100 IU/L attributable to APAP toxicity. Cases were identified by electronic search of hospital laboratory database and by discharge diagnosis corroborated by structured explicit medical record review. Results: Of 68 cases identified (mean age (SD): 39 (18) years, 63% female, and 21% ethanol co-ingested), 28 (41%) developed hepatotoxicity (peak AST or ALT > 1000 IU/L), 28 (41%) coagulopathy (international normalized ratio or INR > 2), and 21 (31%) both. Three patients (4%) were transferred for liver transplantation and ultimately six (8.8%) died. Serum AST and ALT activity rose in a closely aligned 1:1 AST:ALT ratio, but fell at distinctly different rates: AST activity fell with a half-life (interquartile range [IQR]) of 15.1 (12.2, 19.4) hours, and ALT 39.6 (32.9, 47.6) hours. Using an aminotransferase falling to below 50% of peak as the basis for discontinuing acetylcysteine would have resulted in antidotal treatment being stopped 24 (IQR: 9.6, 40) hours earlier (and in no cases later) using AST rather than ALT. Only six patients had an AST:ALT ratio greater than 2:1 at the time of acetylcysteine administration; of these six, four died and one survivor developed coagulopathy. Discussion: AST and ALT release into the circulation appears tightly linked and numerically similar, except in the sickest patients. Once the aminotransferases peak, AST returns to baseline more quickly. Conclusion: Either AST or ALT can be used for early risk stratification tools when only one is known. Any criterion for N-AC discontinuation should be based on the decline of AST rather than ALT, with a potential benefit measured in days.     

Cardioprotective effect of Nerium oleander flower against isoproterenol-induced myocardial oxidative stress in experimental rats

Nerium oleander Linn (NOL) an evergreen shrub belonging to the Apocynaceae family has been reported to have a wide spectrum of bioactivities. In in vitro study, the free radical scavenging potential of the hydroethanolic extract of N oleander Linn (ENO) flower and its fractions (glycosidic and nonglycosidic) were studied using 2, 2(')-azino-di [3-ethylbenzthiazoline sulphonate] (ABTS(*+) ) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH*) scavenging assay. ENO exhibited better radical scavenging activities than its fractions. Furthermore, the cardioprotective role of ENO (10, 30, 100 mg/kg, per oral [po]) was tested against isoproterenol-induced myocardial toxicity (ISO, 120 mg/kg per day, subcutaneously [sc], for 2 days at 48 hours interval) in experimental rats when compared to propranolol (5 mg/kg, po) which was the standard. Pretreatment with ENO (10, 30, and 100 mg/kg) and propranolol for 2 weeks followed by ISO challenge in rats prevented the elevation of marker enzymes such as lactate dehydrogenase (LDH), γ-glutamyl transferase (GGT), creatine kinase (CK-MB and creatine phosphokinase [CPK]), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) in plasma. In addition, pretreatment with ENO and propranolol significantly attenuated the lipid peroxidation by maintaining the levels of enzymatic (superoxide dismutase and glutathione peroxidase) and nonenzymatic antioxidants (reduced glutathione and nitrite), which was also confirmed histologically. Taken together, the current study indicates that the hydroalcoholic extract of N oleander Linn flowers aid in cardioprotection probably by improving the antioxidant defense system during experimental myocardial necrosis.     

三种临床血清酶国际、国内实验室比对结果分析及其参考方法的评估

目的分析2006年度至2007年度连续2年参加国际临床化学联合会（IFCC）的参考实验室丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、乳酸脱氢酶（LDH）的室间质评（RELA）结果及卫生部临床检验标准委员会（以下简称卫生部）的酶学室间比对结果,评估其所用测定参考方法的检测质量及其完善程度。方法根据IFCC公布的ALT、AST、LDH的测定参考方法的标准操作程序（SOP）进行测定,根据《分析测量中不确定度的量化》（QUAM2000）计算合成标准不确定度,用日本临床检验标准协议会（JCCLS）旭化成株式会社认证酶标准物质评估参考方法的分析性能（准确度与不精密度）。结果2006年度的国际RELA与卫生部酶学室间比对结果室内变异系数（CV）均在1．5％～2．1％,2007年度的国际RELA结果与卫生部酶学室问比对结果室内CV均在1．1％以下,且本实验室与总体均值的偏倚整体低于2006年度,除2006年度卫生部酶学室间比对结果有3个值与总体均值的偏倚（7．99％,-7．02％,-13．97％）超过允许偏倚外,其余值均在允许偏倚范围内。ALT、AST、LDH标准物质室内CV均在1％以下,且均值偏倚靶值均低于1％。结论本实验室所用测定ALT、AST、LDH的参考方法已比较成熟稳定,2007年度的实验室比对结果优于2006年度。     

染料木素对肝损伤后促进肝功能恢复的实验研究

目的探讨染料木素对硫代乙酰胺（TAA）所致肝损伤的保护作用，并分析其可能的临床他用价值。方法Wistar雄性大鼠腹腔给予硫代乙酰胺法建立急性肝损伤模型。肝损伤的同时，治疗组皮下给予溶于DMSO的染料木素，对照组皮下给予二甲基亚砜（DMSO），正常组由同样途径给予生理盐水。在最后一次注射硫代乙酰胺36h后分析大鼠外周血中肝功能指标，并进行肝病理学分析。结果在建使1周内对照组死亡4只（病死率33．33％），治疗组和正常组未出现死亡（P〈0．05）。治疗组和对照组大鼠体重显菩减轻（P〈0．01），在停止注射TAA 36h后，三组行非参数统计比较，发现除乳酸脱氢酶（LDH）差异无统计学意义外，谷丙转氨酶（ALT）、谷草转氨酶（AST）、总胆红素（TBIL）、谷氨酰转移酶（γ-GT）、碱性磷酸酶（ALP）、胆汁酸（TBA）均存在明显差异（P〈0．05）。治疗组与对照组比较，除AST、γ-GT无统计学差异外，ALT、TBIL、ALP、TBA、LDH都存在不同程度的降低（P〈0．05）。但各组病理学检查术发现有明显差异．结论染料木素对肝损伤后肝功能恢复有一定的促进作用。     

Aminotransferase as a prognostic index in infants with liver disease

To assess the utility of the serum aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio in a group of infants with liver disorders, we retrospectively analyzed the charts of 73 infants with chronic liver disorders. Patients were considered as having either a good outcome (n = 40) or a poor outcome (n = 33), based upon the clinical course. AST and ALT in serum were measured simultaneously at the time of initial presentation and at various follow-up visits during the first 13 months after birth. At presentation (mean age 1.65 months), there was no difference in the AST/ALT ratios between the good (1.61 +/- 0.62; mean +/- SD) and poor (1.65 +/- 0.78) outcome groups (P = 0.81). However, over time, the AST/ALT ratio increased in patients in the poor-outcome group and decreased in patients in the good-outcome group. Calculating the AST/ALT ratio appears to be an easy, early, and reliable prognostic indicator for infants with hepatic disease, and may be a useful measure for evaluating liver-disease patients.     

胸部开放伤后海水浸泡对实验犬肝功能及形态学的影响

目的：探讨胸部开放伤后海水浸泡对实验犬肝功能及其病理形态学的影响。方法：实验动物伤后随机分为对照组（n=10)和海水浸泡组(n=10)。对照组为单纯胸外伤,海水浸泡组的动物于致伤后置入人工配制的海水中。致伤前及入水15、30、45分钟以及1、2、3和4小时取血测定总胆红素、丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）、乳酸脱氢酶（LDH）和碱性磷酸酶（AKP）,同时对肝组织进行光镜及透射电镜检查。结果：海水浸泡组血液总胆红素、ALT、AST和LDH明显升高并且出现时间早,肝脏有明显的病理形态学改变,而对照组肝功能改变轻微且出现时间晚。结论：海水浸泡可导致实验犬的肝功能损伤和肝细胞病理形态学变化。     

Mitochondrial and cytoplasmic isoenzymes of aspartate aminotransferase in sera of patients after myocardial infarction

Mitochondrial and cytoplasmic isoenzymes of aspartate aminotransferase (AST) were studied in the sera of 42 patients following acute myocardial infarction and compared to creatine kinase (CK), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT). Mitochondrial AST( ASTm ) was detected in 93% (39/42) of patients. Maximum recorded ASTm activity was 59.5 +/- 8.8 U/l and was found 39.4 +/- 3.5 hours after the onset of symptoms (chest pain) of myocardial infarction. In contrast the maximum recorded cytoplasmic AST ( ASTc ) activity was greater (327 +/- 23 U/l) and it occurred earlier (33.5 +/- 2.2 hours) after onset of infarction compared to ASTm . ASTm correlated significantly (p less than 0.05) with ASTc , LDH and ALT but not with total CK or CK-MB. ASTc correlated significantly (p less than 0.05) with total CK, CK-MB and LDH but not ALT. Maximum recorded ASTm activity was significantly associated with the clinical assessment of left ventricular failure ( Killip classification) but not with ventricular arrhythmias. In a subset of 15 patients evaluated with invasive hemodynamic measurements of cardiac output and pulmonary capillary wedge pressure. ASTm correlated significantly (p less than 0.05) and better than CK-MB with the hemodynamic assessment of left ventricular dysfunction. Thus ASTSm can be readily identified in sera of patients after acute myocardial infarction and may be of value in the evaluation of patients with acute myocardial infarction.     

异氟醚预处理对缺血/再灌注复合内毒素大鼠肝脏损伤的影响

目的 观察再灌注期腹腔注射内毒素脂多糖(LPS)对大鼠肝脏缺血/再灌注(I/R)损伤的影响以及异氟醚(ISO)预处理的干预作用.方法 将32只SD大鼠随机均分为4组:假手术(Sham)组、单纯肝脏I/R组、肝脏I/R复合LPS损伤(I/R+LPS)组及ISO预处理组.I/R+LPS组吸氧预处理后间隔0.5 h进行肝脏缺血1 h、再灌注4 h,再灌注开始时腹腔内注入LPS;ISO预处理组以ISO吸入预处理0.5 h,间隔0.5 h后进行I/R损伤操作,再灌注开始时腹腔内注入LPS.再灌注4 h处死各组动物,留取肝脏及血液标本;观察各组肝组织病理学改变,血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、肿瘤坏死因子-α(TNF-α)的变化以及肝组织TNF-α、髓过氧化物酶(MPO)活性的改变.结果 与Sham组比较,损伤各组血清ALT、AST、TNF-α及肝组织TNF-α、MPO活性均显著升高(P均＜0.01);与I/R组比较,I/R+LPS组肝脏损伤和炎症细胞因子反应明显较重(P＜0.05或P＜0.01)l与I/R+LPS组比较,ISO预处理组肝脏的病理损伤明显较轻,血清ALT、AST、TNF-α水平及肝组织MPO活性和促炎细胞因子TNF-α的表达水平均显著降低(P均＜0.05).结论 再灌注期复合LPS腹腔注射明显加重了肝脏的损伤和炎症细胞因子反应,ISO预处理可明显减轻复合损伤介导的炎症反应,保护肝脏.