Effects of Hypothermia on Blood Endogenous Endotoxin Levels During Cardiopulmonary Bypass

A bstract Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24–28°C) and mild (32–34°C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 ± 1.2°C in group 1 and 33.8 ± 0.8°C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered.     

Melatonin ameliorates chronic renal failure-induced oxidative organ damage in rats

Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species (ROS). Melatonin, the chief secretory product of the pineal gland, was recently found to be a potent free radical scavenger and antioxidant. The aim of this study was to examine the role of melatonin in protecting the aorta, heart, corpus cavernosum, lung, diaphragm, and kidney tissues against oxidative damage in a rat model of CRF, which was induced by five of six nephrectomy. Male Wistar albino rats were randomly assigned to either the CRF group or the sham-operated control group, which had received saline or melatonin (10 mg/kg, i.p.) for 4 wk. CRF was evaluated by serum blood urea nitrogen (BUN) level and creatinine measurements. Aorta and corporeal tissues were used for contractility studies, or stored along with heart, lung, diaphragm, and kidney tissues for the measurement of malondialdehyde (MDA, an index of lipid peroxidation), protein carbonylation (PC, an index for protein oxidation), and glutathione (GSH) levels (a key antioxidant). Plasma MDA, PC, and GSH levels and erythrocytic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in CRF. In the CRF group, the contraction and the relaxation of aorta and corpus cavernosum samples decreased significantly compared with controls (P < 0.05-0.001). Melatonin treatment of the CRF group restored these responses. In the CRF group, there were significant increases in tissue MDA and PC levels in all tissues with marked reductions in GSH levels compared with controls (P < 0.05-0.001). In the plasma, while MDA and PC levels increased, GSH, SOD, CAT, and GSH-Px activities were reduced. Melatonin treatment reversed these effects as well. In this study, the increase in MDA and PC levels and the concomitant decrease in GSH levels of tissues and plasma and also SOD, CAT, GSH-Px activities of plasma demonstrate the role of oxidative mechanisms in CRF-induced tissue damage, and melatonin, via its free radical scavenging and antioxidant properties, ameliorates oxidative organ injury. CRF-induced dysfunction of the aorta and corpus cavernosum of rats was reversed by melatonin treatment. Thus, supplementing CRF patients with adjuvant therapy of melatonin may have some benefit.     

Renal cell carcinoma metastases to gallbladder

A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously.     

麦冬多糖对正常和实验性糖尿病小鼠血糖的影响

目的：研究麦冬多糖对正常和实验性糖尿病小鼠血糖的影响。方法：昆明种小鼠４０只，分成４组，分别用麦冬多糖（１００和３００ｍｇ／ｋｇ）、优降糖（２．５ｍｇ／ｋｇ）和等体积生理盐水（２ｍｌ／只）灌胃，测定各组正常小鼠的血糖水平及以葡萄糖（２ｇ／ｋｇ）、四氧嘧啶（７０ｍｇ／ｋｇ）、肾上腺素（０．０２ｍｇ／ｋｇ）所致小鼠高血糖模型的血糖水平。结果：剂量为１００和３００ｍｇ／ｋｇ的麦冬多糖灌胃对葡萄糖、四嘧啶     

Ascorbic acid levels in human tears after photorefractive keratectomy, transepithelial photorefractive keratectomy, and laser in situ keratomileusis

PURPOSE: To investigate the level of ascorbic acid in human tear fluid after photorefractive keratectomy (PRK), transepithelial PRK, and laser in situ keratomileusis (LASIK). SETTING: Departments of Ophthalmology and Biochemistry, School of Medicine, Gazi University, Ankara, Turkey. METHODS: Twenty patients (7 women and 13 men) were included in this study. Traditional PRK with epithelial scraping by a blunt spatula followed by surface ablation (7 eyes), transepithelial PRK (7 eyes), or LASIK (6 eyes) was performed. Tears were collected preoperatively and 1 and 5 days postoperatively. Ascorbic acid levels were measured using 2-4 dinitrophenylhydrazine. RESULTS: Ascorbic acid levels in the tear fluid were decreased significantly 1 day after PRK, transepithelial PRK, and LASIK (P <.05). On the fifth day, the ascorbic acid levels were significantly lower than preoperatively in all groups. CONCLUSION: After PRK, transepithelial PRK, and LASIK, the ascorbic acid levels of the tear fluid decreased significantly. Because ascorbic acid is the major scavenger of superoxide radicals in tears, topical ascorbic acid therapy may help eliminate the harmful effect of free radicals from excimer laser surgery.     

用电化学检测器的高效液相色谱法测定血清及尿中速尿的含量

本文报告了用电化学检测器的高效液相色谱法测定血清及尿中速尿含量的方法。样品予处理方法:血清用乙腈除蛋白,尿用蒸馏水稀释50倍。采用作者合成的FD-Val-OH作为内标物。色谱条件为:反相柱,以含35%乙醇的5mmol/L四丁基铵水溶液为流动相(pH7.50),流速1.0ml/min;用电化学检测器,检测电压0.90V:速尿及内标物的保留时间分别为10和15min。通过计算速尿对内标物的峰高比求得速尿含量。血清及尿中的最低检测浓度分别为16和9ng/ml。标准曲线在0.25～5ng/μl(血清)、0.5～10ng/μl(尿)的浓度范围内呈线性关系。血清及尿中回收率分别为100.5%和100.6%。变异系数在4.6%以下。     

电化学方法研究环丙沙星及其镁、锰络合物与脱氧核糖核酸的相互作用

用电化学的方法,研究环丙沙星(CPFX)及其镁、锰络合物与脱氧核糖核酸(DNA)的相互作用及其极谱伏安行为。结果在0.1mol·L^-1NH₃-NH₄Cl(pH9.2)溶液中,环丙沙星可与DNA作用,产生一新的极谱峰 Ep=-1.72V(vsAg/AgCl),在有Mg²⁺或Mn²⁺存在时则生成三元络合物,产生一电位更负的新峰,峰电位Ep=-1.78V,提示Mg²⁺或Mn²⁺离子参与药物与DNA的作用。对它们的还原峰性质研究表明,电极还原反应是完全不可逆的,电流具有吸附性。本文还探讨了电极还原机理,认为参与电极还原的是三元络合物中的环丙沙星分子,进一步推测CPFX-Mg是嵌入DNA的双螺旋结构中。     

3H-1,2-二氢-1-吡里酮衍生物的合成

发现3 H-1,2-二氢-1-吡咯里嗪酮具有明显的抗炎镇痛作用。用Friedel-Crafts酰化和Dieckmann缩合等反应制备了该酮的一些衍生物,其中五个未见于文献报道。药理实验证明,这些化合物均有不同程度的抗炎镇痛作用。