黄芪总黄酮对急性心肌梗死大鼠心脏血流动力学及心肌细胞钙电流的作用

目的探讨黄芪总黄酮（TFA）对急性心肌梗死（AMI）大鼠心脏血流动力学及心肌细胞钙电流的作用。方法大鼠开胸左前降支结扎造成AMI，开胸前5min实验组大鼠舌静脉注射剂量为（20mg／kg）TFA溶液50μl，并设正常对照组，AMI组及TFA实验组，后行血流动力学检查；酶解分离心室肌细胞，采用全细胞膜片钳记录技术记录左前降支供血区心外膜细胞的L型Ca^2＋电流（L—Ica）的作用。结果①应用TFA（20mg／kg）后与AMI组比较，血流动力学指标明显改善（P〈0．05，n=7）。与正常对照组相比差异无统计学意义（P〉0．05，n=7）。②应用TFA（20mg／kg）后与AMI对照组比较，L-型钙电流（L—ICa）由给药前的（0．31±1．09）nA增加到给药后的（0．49±0．89）nA（P〈0．01，n=7）。结论TFA可以明显改善AMI大鼠心脏血流动力学，增加心室肌细胞L-型钙电流的幅值。     

Effects of calcium ions on adenine nucleotide translocase from cardiac muscle

The properties of a specific adenosine nucleotide translocase from rat and pigeon heart mitochondria are similar to those of the system from liver. In particular, the K_m for external ADP is very low, i.e. about 7 μm. The maximum activity of the translocase system, which was measured by following the exchange of adenine nucleotides across the mitochondrial membrane, or the K_m of the system for ADP or ATP were not affected by Ca²⁺ concentration in the range 0.001 to 10 μm. Consequently the concentration change in sarcoplasmic Ca²⁺ that modifies the activities of several key metabolic enzymes plus the myofibrillar ATPase is unlikely to affect the activity of the translocase. However, in confirmation of previous work, higher concentrations of Ca²⁺ (up to 400 μm) increased considerably the exchange of the adenine nucleotides. There is some recent evidence that heart muscle mitochondria possess high affinity binding sites for Ca²⁺ in the mitochondrial membrane, which bind up to 300 nmol Ca²⁺ per g of heart muscle. It is emphasized that, if the adenine nucleotide translocase and the high affinity binding sites for Ca²⁺ are adjacent (or identical), the effects of the higher concentrations of Ca²⁺ on the translocase could be of considerable importance in control of the rate of translocation in heart muscle.     

应激性溃疡的发生及川芎嗪的防治效应

本实验观察了家兔创伤后胃粘膜损伤情况及川芎嗪的防治效应。发现动物创伤后目粘膜损伤严重．出现应激性溃疡．同时血浆和胃粘膜组织中脂质过氧化物商二醇含量增加，且胃粘膜细胞有明显的钙积聚。而应用川芎嗪防治的动物．脂质过氧化反应被明显地抑制，钙超载现象显著减轻．胃粘膜损伤轻微。提示，应激性溃疡的发生与自由基反应和细胞内钙超载有关，川芎嗪对应激性溃疡具有防治作用。     

The effect of orlistat on body weight and coronary heart disease risk profile in obese patients: the Swedish Multimorbidity Study

OBJECTIVE: To assess the effect of orlistat on body weight and cardiovascular risk amongst obese patients at high coronary risk. DESIGN: After screening, patients entered a two-week single-blind placebo lead-in period, during which they followed a mildly hypocaloric diet, before being randomized to double-blind treatment with either orlistat 120 mg or placebo three times daily, in conjunction with dietary intervention for 1 years. SETTING: The study was conducted at 33 primary care centres in Sweden. SUBJECTS: A total of 382 obese adults (body mass index 28-38 kg m-2) with type 2 diabetes, hypercholesterolaemia and/or hypertension were recruited, of whom 376 were randomized to orlistat (n = 190) or placebo (n = 186). MAIN OUTCOME MEASURES: Change in body weight, waist and hip circumferences, blood pressure, serum lipid profile, fasting glucose and HbA1c. RESULTS: After 1 years, mean weight loss was significantly greater with orlistat compared with placebo (5.9% vs. 4.6%; P < 0.05). Moreover, significantly more orlistat-treated patients than placebo recipients maintained weight loss of > or = 5% (54.2% vs. 40.9%; P < 0.001). Orlistat was also associated with significantly greater improvements than placebo in total serum cholesterol (- 3.3% vs. -0.5%; P < 0.05), LDL-cholesterol (- 7.0% vs. -1.1%; P < 0.05), fasting glucose (5.1% vs. -0.1%; P < 0.01) and HbA1c (- 2.7% vs. -0.5%; P < 0.05). Similar results were reported for the subgroup of patients with type 2 diabetes. Orlistat was well tolerated. CONCLUSIONS: Treatment with orlistat in conjunction with diet promotes significantly greater weight loss and cardiovascular risk factor reduction than diet alone amongst obese patients at high risk of future coronary events.     

Effect of a toxic in vivo dose of ouabain on guinea-pig heart mitochondria

The effects of toxic doses of ouabain on two parameters of mitochondrial activity, oxidative phosphorylation and calcium uptake were examined. Ouabain was injected intraperitoneally into guinea-pigs until signs of severe intoxication appeared. State 3 oxygen consumption (Q_O2, State 3, in natom oxygen/mg/min) of isolated heart mitochondria was 314 ± 16 and 281 ± 16 (glutamate-malate) for treated and control group, respectively; 225 ± 21 and 207 ± 23 (pyruvate-malate), and 251 ± 12 and 230 ± 13 (succinate), respectively. The rate of calcium uptake was 411 nmol Ca²⁺/min/mg for treated and 329.6 nmol Ca²⁺/min/mg for control. The rate of calcium release was the same in control and treated groups.The data suggest that increases of respiration and calcium uptake in vitro, if they reflect similar increases in vivo, may contribute to digitalis intoxication by intracellular redistribution of calcium.     

Dietary weight loss in insulin-resistant non-obese humans: Metabolic benefits and relationship to adipose cell size

Background and Aims

Overweight and obesity increase risk for diabetes and cardiovascular disease, largely through development of insulin resistance. Benefits of dietary weight loss are documented for obese individuals with insulin resistance. Similar benefits have not been shown in overweight individuals. We sought to quantify whether dietary weight loss improves metabolic risk profile in overweight insulin-resistant individuals, and evaluated potential mediators between weight loss and metabolic response.

Circulating interleukin-6 is associated with disease progression,but not cachexia in pancreatic cancer

Background

Cachexia is a wasting syndrome characterized by involuntary loss of >5% body weight due to depletion of adipose and skeletal muscle mass. In cancer, the pro-inflammatory cytokine interleukin-6 (IL-6) is considered a mediator of cachexia and a potential biomarker, but the relationship between IL-6, weight loss, and cancer stage is unknown. In this study we sought to evaluate IL-6 as a biomarker of cancer cachexia while accounting for disease progression.

Impacto de la puntuación de calcio en la concordancia entre la tomografía computarizada con multidetectores y la coronariografía invasiva

Introduction and objectives

Multidetector computed tomography (MDCT) has been demonstrated as a feasible alternative to invasive coronary angiography (ICA). However, contradictory results have been reported regarding the effect of coronary artery calcium score (CS) on the diagnostic accuracy of MDCT. Our aim was to assess the agreement of MDCT and ICA and to evaluate the influence of CS on this agreement.