A Phase III, Double-blind, Placebo-controlled, Multicenter Study on the Efficacy of Recombinant Human Antithrombin in Heparin-resistant Patients Scheduled to Undergo Cardiac Surgery Necessitating Cardiopulmonary Bypass

Background: The study evaluated the efficacy of recombinant human antithrombin (rhAT) for restoring heparin responsiveness in heparin resistant patients undergoing cardiac surgery.

Methods: This was a multicenter, randomized, double-blind, placebo-controlled study in heparin-resistant patients undergoing cardiac surgery with cardiopulmonary bypass. Heparin resistance was diagnosed when the activated clotting time was less than 480 s after 400 U/kg heparin. Fifty-four heparin-resistant patients were randomized. One cohort received 75 U/kg rhAT, and the other received normal saline. If the activated clotting time remained less than 480 s, this was considered treatment failure, and 2 units fresh frozen plasma was transfused. Patients were monitored for adverse events.

Results: Only 19% of patients in the rhAT group received fresh frozen plasma, compared with 81% of patients in the placebo group (P < 0.001). During their hospitalization, 48% of patients in the rhAT group received fresh frozen plasma, compared with 85% of patients in the placebo group (P = 0.009). Patients in the placebo group required higher heparin doses (P < 0.005) for anticoagulation. There was no increase in serious adverse events associated with rhAT. There was increased blood loss 12 h postoperatively (P = 0.05) with a trend toward increased 24-h bleeding in the rhAT group (P = 0.06). There was no difference between the groups in blood and platelet transfusions.     

南阳地区5岁以下儿童社区获得性肺炎病原菌检测分析

目的通过对南阳地区≤5岁儿童社区获得性肺炎(CAP)患儿下呼吸道分泌物病原菌的检测，探讨近年儿童CAP病原菌构成和耐药谱的新特点。 方法选择2003 11—2005 12来自南阳地区各不同社区于南阳医专附院儿科就诊，符合肺炎诊断标准的儿童CAP住院患者1276例，用多平板不同条件对未抗菌治疗采得的标本进行接种培养，分离菌株采用Bio Merieux VITEK 2型全自动微生物仪进行菌种鉴定和药物敏感试验，结果采用WHONET5软件分析处理，得出儿童CAP病原菌种分布构成比及主要致病菌种对常用抗菌药物的耐药率。 结果检出病原菌以革兰阴性菌为主，占68.6%(297/433)，其中前3位分别为大肠埃希菌、肺炎克雷伯菌及铜绿假单胞菌。6种主要革兰阴性菌对氨苄西林、复方磺胺、头孢唑啉显示高抗药性，而对美洛培南、亚安培南高度敏感，对阿米卡星、头孢吡肟较敏感。4种主要革兰阳性菌对万古霉素高度敏感，对利福平、氨苄西林/舒巴坦及左氧氟沙星较敏感。 结论儿童CAP病原菌构成在发生变迁，细菌的耐药性也在发生改变，且各地及不同时期存在差异，故应作好病原及药敏监测并改进检测方法，掌握本地区一定时期内儿童CAP的病原学情况。     

睡眠障碍可能是发生男性心肌梗死的一个危险因素

[俄]/ГаФаров ВВ…//Клин Мед.—2006,84(4).—28～30睡眠是机体的自然生理状态,对保持机体各器官和系统的正常功能十分重要;而睡眠障碍则是影响健康的因素之一。根据世界卫生组织专家委员会关于研究睡眠障碍的资料,美国有36%成年人睡眠不正常,有4千万人患慢性     

Effects of Volatile Anesthetics on Glutamate Transporter, Excitatory Amino Acid Transporter Type 3: The Role of Protein Kinase C

Background: Glutamate transporters play an important role in maintaining extracellular glutamate homeostasis. The authors studied the effects of volatile anesthetics on one type of glutamate transporters, excitatory amino acid transporter type 3 (EAAT3), and the role of protein kinase C in mediating these effects.

Methods: Excitatory amino acid transporter type 3 was expressed in Xenopus oocytes by injection of EAAT3 mRNA. Using two-electrode voltage clamp, membrane currents were recorded before, during, and after application of l-glutamate. Responses were quantified by integrating the current trace and are reported as microcoulombs. Data are mean +/- SEM.

Results: l-Glutamate-induced responses were increased gradually with the increased concentrations of isoflurane, a volatile anesthetic. At 0.52 and 0.70 mm isoflurane, the inward current was significantly increased compared with control. Isoflurane (0.70 mm) significantly increased Vmax (maximum velocity) (3.6 +/- 0.4 to 5.1 +/- 0.4 [mu]C;P < 0.05) but not Km (Michoelis-Menten Constant) (55.4 +/- 17.0 vs. 61.7 +/- 13.6 [mu]m;P > 0.05) of EAAT3 for glutamate compared with control. Treatment of the oocytes with phorbol-12-myrisate-13-acetate, a protein kinase C activator, caused a significant increase in transporter current (1.7 +/- 0.2 to 2.5 +/- 0.2 [mu]C;P < 0.05). Responses in the presence of the combination of phorbol-12-myrisate-13-acetate and volatile anesthetics (isoflurane, halothane, or sevoflurane) were not greater than those when volatile anesthetic was present alone. Oocytes pretreated with any of the three protein kinase C inhibitors alone (chelerythrine, staurosporine, or calphostin C) did not affect basal transporter current. Although chelerythrine did not change the anesthetic effects on the activity of EAAT3, staurosporine or calphostin C abolished the anesthetic-induced increase of EAAT3 activity.     

Perflubron Emulsion in Prolonged Hemorrhagic Shock: Influence on Hepatocellular Energy Metabolism and Oxygen-dependent Gene Expression

Background: Liver dysfunction as a result of impaired oxygen availability frequently occurs following hemorrhage and contributes to delayed mortality. Artificial oxygen carriers may improve oxygen supply to vital organs while avoiding the need for allogeneic transfusion.

Methods: Rats were subjected to hemorrhagic hypotension (mean arterial pressure = 35-40 mmHg for 120 min) and were subsequently resuscitated with (1) stored whole rat blood, (2) pentastarch, or (3) pentastarch combined with perflubron emulsion (PFE; 2.7 or 5.4 g/kg body weight), a second-generation artificial oxygen carrier. Recovery of liver adenosine triphosphate, hepatocellular injury, and expression of glutamine synthetase 1, a gene that is induced by exposure of hepatocytes to low partial pressure of oxygen, were studied at 4 h of resuscitation.

Results: Stored whole blood or pentastarch failed to restore liver adenosine triphosphate concentrations after prolonged shock as compared to sham controls and resulted in increased gene expression of glutamine synthetase 1. Addition of 2.7 g PFE/kg restored liver adenosine triphosphate to control, whereas 5.4 g PFE/kg resulted in adenosine triphosphate concentrations significantly above control. Improved hepatocellular oxygen supply was also confirmed by restoration of the physiologic expression pattern of glutamine synthetase 1. Serum enzyme concentrations were highest after resuscitation with stored blood, whereas addition of PFE failed to further decrease enzyme concentrations as compared to pentastarch alone.     

糖尿病人的低镁与其心脏并发症的关系

糖尿病患者心血管并发症发生率较高，这与它常伴有镁缺乏有一定关系，在镁缺乏情况下，心肌、平滑肌代谢和生理功能易发矿生异常，还可引起冠状动脉痉挛和心室颤动，导致心脏病患者摔死，故纠正镁代谢紊乱有助于防治糖尿病心脏并发症，有利于糖尿病病人的康复。由于镁离子是血清肌酸激酶激活的必需离子、糖尿病患者镁离子的消耗增加和摄入不足使血浆和肌肉细胞中镁含量降低，肌酸激酶活性下降。当补充镁（15．8mml/L）1个月后，胰岛素的敏感性将增高。我们观察发现：非胰岛素依赖型糖尿病患者每日静注硫酸镁10ml和门冬氨酸钾镁20ml两周后，…     

Colonization of America by Drosophila subobscura: Experiment in natural populations that supports the adaptive role of chromosomal-inversion polymorphism

North America and South America have recently been colonized by the Palearctic species Drosophila subobscura. This double colonization offers a rare opportunity for evolutionary studies. Correlations between chromosomal arrangement frequencies and latitude were calculated for the colonizing populations. Signs of these correlations are highly coincident with those found in the Old World. These results provide experimental support for the adaptive value of the chromosomal-inversion polymorphism; historical and other nonadaptive explanations are thus excluded or relegated to a secondary role.     

In Uruguay, an ethic of care for the dying

The ethics of care for the terminally ill in Uruguay spring from deeply rooted attitudes which invest the physician with sole power to determine the course of treatment, even to prescribe painkilling drugs and to hasten death actively or passively, without collaboration from the patient's family. The paternal function attributed to the physician has not been questioned by any systematic reflection on biomedical ethics. However, conscientious physicians are interested in these issues and are well informed about the concerns of their foreign colleagues.     

Monitoring gamma-aminobutyric acid in human brain and plasma microdialysates using micellar electrokinetic chromatography and laser-induced fluorescence detection

Due to its low electrophoretic mobility, few studies have been able to measure gamma aminobutyric acid (GABA) in biological samples by means of capillary zone electrophoresis. Nevertheless, in micellar electrokinetic chromatography (MEKC) by adding a surfactant to the mobile phase separation can be carried out on the basis of the partition coefficient of the molecules rather than their electrophoretic mobility. In the present study microdialysis coupled to MEKC with laser induced fluorescence detection was used to successfully monitor GABA from cerebrospinal fluid and plasma dialysates. Moreover, we monitored changes in extracellular GABA from a human brain. Microdialysis samples were collected from a Parkinson's disease patient undergoing a thallamotomy as part of her treatment. Significant decreases in extracellular GABA were detected during high frequency electrical stimulation and following a thermolesion of the thalamus. These results demonstrate the feasibility of MEKC coupled to laser-induced fluorescence detection in resolving neutral amino acids, specifically GABA, from different human body fluids.