丹参对缺氧/复氧心肌的保护作用涉及百日咳毒素敏感的G蛋白

目的　研究丹参注射液对缺氧/复氧心肌细胞的保护作用及其机制。方法　采用酶解分离成年大鼠心室肌细胞化学缺氧模型,用视频跟踪计算机系统、细胞内双波长钙荧光系统和光学法分别观察心肌细胞收缩力学、细胞内钙和乳酸脱氢酶(LDH)释放等指标。结果　丹参(3g/L)处理后降低心肌细胞最大收缩和舒张速率、收缩幅度以及电刺激诱导的钙瞬态幅度。缺氧导致细胞收缩力和钙瞬态幅度降低、舒张末细胞长度缩短、舒张末钙水平增高,复氧后各指标有所回复。缺氧/复氧引起LDH释放增多。用3g/L的丹参处理后,缺氧/复氧引起的心肌细胞最大收缩和舒张速率、收缩幅度和电刺激诱导的钙瞬态幅度高于单纯缺氧组,舒张末钙水平低于单纯缺氧组,LDH释放减少。预先用百日咳毒素处理,丹参引起的心肌保护作用被减弱。结论　丹参可能通过百日咳毒素敏感的G蛋白发挥对缺氧/复氧损伤心肌的保护作用     

荭草苷对缺氧-复氧心肌细胞的保护作用

目的探讨荭草苷 (orientin)对缺氧 复氧损伤心肌细胞的保护作用及其机制。方法采用原代培养的新生大鼠心肌细胞建立缺氧 复氧损伤模型 ,实验分为正常细胞培养组、缺氧 复氧损伤模型组、缺氧 复氧损伤 +荭草苷 (3、10、30 μmol·L-1)组、缺氧 复氧损伤 +verapamil(5 μmol·L-1)组。用黄嘌呤氧化酶法测定SOD的活力 ,硫代巴比妥酸显色法测定MDA含量 ,MTT染色法测定线粒体脱氢酶活性改变并测定LDH含量变化 ,荧光法测定细胞内钙浓度的变化。结果荭草苷可显著提高缺氧 复氧损伤心肌细胞内SOD的活性及细胞内线粒体脱氢酶活性 ,并能显著抑制LDH的活性、MDA的生成以及细胞内钙浓度。结论荭草苷具有明显的抗缺氧 复氧损伤 ,保护心肌细胞的作用     

地氟醚、七氟醚和异氟醚预处理增加缺氧复氧心肌细胞ATP的贮存

目的研究地氟醚、七氟醚和异氟醚预处理对缺氧/复氧心肌细胞ATP含量影响及其与细胞损害的关系。方法原代培养乳鼠心肌细胞随机分为对照、单纯缺氧/复氧及1.5肺泡气最低有效浓度(MAC)地氟醚、七氟醚和异氟醚预处理5组。实验结束测定心肌细胞内ATP、心肌酶LDH和CK、细胞存活率。结果1.5MAC地氟醚、七氟醚和异氟醚预处理显著减轻缺氧/复氧引起的ATP含量和细胞存活率下降 ,以及LDH和CK的升高 ;ATP含量变化与LDH和CK呈负相关 (r分别为 -0.87和 -0.82 ,P<0.01) ,与细胞存活率呈正相关 (r为0.83 ,P<0.01)。结论地氟醚、七氟醚和异氟醚预处理可增加缺氧/复氧心肌细胞内ATP ,是其心肌保护机制之一。     

三七二醇对缺氧/复氧心肌细胞的保护机制及HSP70表达影响的研究

目的：探讨三七二醇对缺氧/复氧心肌细胞的保护机制及HSP70表达的影响。方法：选择刚出生的SD大鼠作心肌细胞原代培养及缺氧/复氧模型。将原代培养大鼠心肌细胞分为5组,A组为对照组;B组为缺氧/复氧对照组;C组为三七二醇低浓度组,D组为三七二醇中浓度组,E组为三七二醇高浓度组。用免疫组织化学法检测HSP70的表达,用生化比色法检测LDH活力。结果：三七二醇对SD大鼠缺氧/复氧心肌细胞具有明显保护作用,保护作用与三七二醇浓度有关。随着三七二醇浓度增加,缺氧/复氧心肌细胞HSP70表达增加,同时随时间延长,SD大鼠缺氧/复氧损伤心肌细胞内HSP70表达增加。结论：三七二醇对缺氧/复氧心肌细胞保护作用可能与HSP70表达增加有关。不同浓度的三七二醇对缺氧/复氧心肌细胞的保护均起一定作用。     

附子多糖对缺氧/复氧乳鼠心肌细胞的保护机制

目的以细胞凋亡的线粒体信号通路为着眼点,对附子多糖对缺氧/复氧后心肌细胞的保护机制进行探讨。方法建立乳鼠心肌细胞缺氧/复氧模型,将乳鼠心肌细胞分为正常对照组、缺氧/复氧组、缺氧后适应组和附子多糖组。缺氧/复氧组给予心肌细胞缺氧3 h后复氧6 h;缺氧后适应组在细胞缺氧3 h后,复氧前即给予3个循环的5 min复氧/5 min缺氧,随后复氧6 h;附子多糖组在缺氧3 h后,将心肌细胞换入含附子多糖浓度为10 g.L?1的培养液中常规培养6 h。流式细胞仪测定心肌细胞凋亡率和线粒体膜电位,进行凋亡诱导因子(AIF)的Western blotting分析,检测心肌细胞内SOD活性和MDA含量。结果与缺氧/复氧组相比较,附子多糖后处理可以保护心肌细胞SOD活性,减少MDA的生成,阻止线粒体膜电位的下降,抑制AIF自线粒体向胞浆的释放,减少心肌细胞凋亡率。结论附子多糖后处理对缺氧/复氧后心肌细胞的保护机制与其抗氧化损伤,抑制细胞凋亡的线粒体信号途径有关。     

JAK2/STAT3调节抗增殖蛋白表达在H_2S后处理心肌细胞中的保护作用

目的探讨JAK2/STAT3信号通路是否通过调节抗增殖蛋白而在硫化氢(H2S)后处理中减轻缺氧/复氧(H/R)心肌细胞的损伤。方法体外培养的原代新生大鼠心肌细胞建立缺氧/复氧损伤模型。随机分为6组:正常对照组(Normal组)、缺氧/复氧组(H/R组)、硫化氢后处理组(NP组)、硫化氢后处理+AG490组(N+A组)、AG490组(AG组)、溶媒组(DMSO组)。分别在缺氧前、复氧2 h检测心肌细胞的存活率、培养液中LDH的释放;复氧末,采用流式细胞术观察各组心肌细胞的凋亡情况;应用Western blot方法检测tSTAT3、p-STAT3、PHB蛋白的表达情况。结果缺氧前,组间各个指标检测值差异未见统计学意义(P>0.05)。复氧2h,与H/R组比较,NP组心肌细胞存活率明显提高了(P<0.05),LDH的释放以及细胞凋亡率明显降低(P<0.05);同时p-STAT3、PHB蛋白表达水平明显升高。AG490逆转了H2S后处理产生的心肌保护效应,使N+A组细胞活力及pSTAT3、PHB的表达水平降低(P<0.05),细胞凋亡率明显增加(P<0.05)。结论 JAK2/STAT3信号通路可能通过上调抗增殖蛋白的表达而在硫化氢(H2S)后处理中减轻心肌细胞缺氧/复氧损伤。     

丹参水提物对乳鼠心肌细胞缺氧-复氧损伤的保护作用

本文研究丹参水提物对乳鼠心肌细胞缺氧-复氧损伤的保护作用。以乳鼠心室肌进行心肌细胞培养并建立缺氧-复氧损伤模型,检测不同浓度丹参水提物预处理后细胞的存活率,乳酸脱氢酶(LDH)、肌酸激酶(CK)、天冬氨酸转移酶(AST)的泄漏量及Akt的磷酸化水平。丹参水提物对缺氧-复氧损伤的心肌细胞具有明显的保护作用,这可能与它激活PI3K/Akt信号通路有关。     

川芎嗪对复氧后损伤心肌细胞的影响

目的：观察川芎嗪对大鼠心室肌细胞缺氧－复氧损伤的作用,方法：在缺氧－复氧条件下,测量对照组和不同浓度川芎嗪组对杆形心肌细胞百分比,心肌细胞释放乳酸脱氢酶（LDH）和心肌细胞类脂过氧化产物－丙二醛（MDA）含量。结果：缺氧－复氧对大鼠心室肌细胞有损伤作用。浓度为4umol/L的川芎开始对缺氧－复氧损伤细胞有保护作用,它能抑制损伤细胞挛缩,提高损伤细胞生存率,抑制细胞LDH的释放,减少MDA的生成,且剂量越大,保护作用越好,即川芎嗪对缺氧－复氧损伤细胞的保护呈剂量依赖性,结论：川芎嗪对缺氧一复氧损伤的心肌细胞具有保护作用。它能显著地对抗缺氧－复氧对心室肌细胞的损伤。     

PI3K/Akt/FoxO3a/Bim信号通路介导硫化氢后处理对缺氧H9c2心肌细胞的保护作用

目的探讨硫氢化钠(Na HS)后处理是否通过PI3K/Akt/Fox O3a/Bim信号通路调节细胞凋亡发挥减轻心肌细胞缺氧/复氧(H/R)损伤的作用。方法 H9c2大鼠心肌细胞缺氧3 h/复氧6 h,建立缺氧/复氧损伤模型。将细胞随机分为5组:空白组(Control组)、缺氧/复氧组(H/R组)、硫氢化钠后处理组(H/R+Na HS组)、抑制剂LY294002组(H/R+LY组)、硫氢化钠后处理+LY294002组(H/R+Na HS+LY组)。分别在缺氧前、复氧末检测H9c2心肌细胞的存活率以及LDH释放;流式细胞术检测各组的细胞凋亡率;应用Western blot检测Akt、p-Akt、Fox O3a、p-Fox O3a、Bim蛋白的表达水平;免疫荧光检测Fox O3a的分布情况。结果缺氧前各组心肌细胞存活率、LDH释放量差异无统计学意义(P>0.05)。复氧末,Na HS组与H/R组相比,心肌细胞存活率明显提高(P<0.05),LDH释放量与细胞凋亡率明显降低(P<0.05);p-Akt、p-Fox O3a蛋白表达水平升高,Bim表达降低,同时Fox O3a在细胞质的表达升高。LY294002逆转了Na HS后处理产生的心肌细胞保护作用,使得H/R+Na HS+LY组的心肌细胞存活率降低(P<0.05)、LDH释放和细胞凋亡率升高(P<0.05),p-Akt、p-Fox O3a蛋白表达降低(P<0.05),Bim表达升高(P<0.05),FoxO 3a在细胞质的表达水平降低。结论硫氢化钠(NaH S)后处理通过PI3K/Akt/FoxO 3a/Bim信号通路调控细胞凋亡,减轻心肌细胞缺氧/复氧(H/R)损伤。     

缺氧-复氧对心室肌细胞的损伤及川芎嗪的保护作用

目的观察缺氧_复氧对大鼠心室肌细胞的损伤及川芎嗪的保护作用。方法在缺氧_复氧条件下 ,测量对照组和不同浓度川芎嗪组对杆形心肌细胞百分比、心肌细胞内K /Na 浓度比及Ca2 浓度的影响。结果缺氧_复氧对大鼠心室肌细胞有损伤作用 ,浓度为4μmol·L -1 的川芎嗪对缺氧_复氧损伤细胞有保护作用 ,它能抑制损伤细胞挛缩 ,提高损伤细胞生存率 ,抑制心肌细胞内K /Na 浓度比的降低、增加细胞内Ca2 浓度 ,且剂量越大 ,保护作用越好 ,即川芎嗪对缺氧_复氧损伤细胞的保护呈剂量依赖性。结论川芎嗪对缺氧_复氧损伤的大鼠心肌细胞具有保护作用 ,它能显著地对抗缺氧_复氧对心室肌细胞的损伤作用     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

Polymorphisms in genes involved in neurotransmission in relation to smoking

Smoking behavior is influenced by both genetic and environmental factors. The genetic contribution to smoking behavior is at least as great as its contribution to alcoholism. Much progress has been achieved in genomic research related to cigarette-smoking within recent years. Linkage studies indicate that there are several loci linked to smoking, and candidate genes that are related to neurotransmission have been examined. Possible associated genes include cytochrome P450 subfamily polypeptide 6 (CYP2A6), dopamine D₁, D₂, and D₄ receptors, dopamine transporter, and serotonin transporter genes. There are other important candidate genes but studies evaluating the link with smoking have not been reported. These include genes encoding the dopamine D₃ and D₅ receptors, serotonin receptors, tyrosine hydroxylase, trytophan 2,3-dioxygenase, opioid receptors, and cannabinoid receptors. Since smoking-related factors are extremely complex, studies of diverse populations and of many aspects of smoking behavior including initiation, maintenance, cessation, relapse, and influence of environmental factors are needed to identify smoking-associated genes. We now review genetic polymorphisms reported to be involved in neurotransmission in relation to smoking.     

我院2004年门急诊处方及抗菌药物合理应用分析

目的了解我院抗菌药物使用状况,为临床合理用药提供参考依据。方法随机抽取2004年门急诊处方样本2444份,依据统计学方法归纳制表并进行综合分析。结果2004年门急诊每张处方药品数平均为3.24种;注射给药处方数占西药总处方数的33.43%,高于北京三甲医院水平(约10%);抗菌药物使用率为43.54%,高于上海、武汉等城市水平(约35%);一线抗菌药物使用率为70.56%,二线抗菌药物使用率为29.37%,抗菌药物分级使用状况总体符合规定;抗菌药物联合用药比率为26.22%,单一用药比率达73.78%,属基本合理范围。结论我院抗菌药用药以一线抗菌药物为主,合理用药是主流,但也存在一定问题,宜制定相应措施,提高用药合理性和安全性。     

Enteroviral meningitis in children in Turkey

In the indexed medical literature, there have been a very limited number of studies to investigate the epidemiologic and clinical features of enteroviral meningitis in Turkey. The aim of the present retrospective study is to update the actual situation to recognize the spectrum and magnitude of this important clinical entity. Between June 1999 and December 2004, 612 cases of aseptic meningitis were followed up at our hospital. Enteroviral meningitis was defined by isolation of enteroviruses from cerebrospinal fluid (CSF) and/or stool samples. Mumps virus was detected in 310 cases (50.7%) and enteroviruses were the etiologic agents in 104 (17%) of the patients with aseptic meningitis. Most of the enteroviral meningitis cases (36 cases, 34.6%) were diagnosed in August and 70 (67.3%) of them were male. The mean age was 5.6 ± 3.4 years. The most common initial symptoms were fever (81.7%), vomiting (77.9%) and headache (57.7%). In the physical examination, 46.2% of the cases had neck stiffness and 38.5% had pharyngitis. Echovirus 30 was the most frequently (38 cases, 36.5%) isolated enterovirus with peaks in 1999, 2002 and 2004. The other frequently isolated enteroviruses were Coxsackie virus type B (17 cases, 16.3%), echovirus 6 (11 cases, 10.6%), echovirus 11 (6 cases, 5.8%), and echovirus 13 (4 cases, 3.8 %). Mean hospitalization time was 6.2 ± 2.4 days. All patients recovered without any sequelae. Enteroviruses have an important role in childhood aseptic meningitis cases in Turkey too, and the predominant serotypes vary according to years.     

Disease control in asthmatic children seen in private practice in Switzerland

ABSTRACT

Background: Asthma is the most common chronic childhood disease in Switzerland with a prevalence of 10%. Asthma has a high economic burden accounting for high medical costs. Assessment of disease control is likely to be of help in the implementation of strategies to improve asthma. Therefore, we aimed to evaluate asthma control and therapy regimens among children in private practice.

Methods: We assessed asthma control as well as therapy regimens in 575 asthmatic children in an experience programme in Switzerland by using an abbreviated questionnaire based on the asthma control questionnaire and the child health questionnaire on Visit 1 and Visit 2.

Results: Good asthma control at Visit 1 was only present in 25.7% of asthmatic children. Occasional asthma symptoms, limitation of physical activity, nocturnal awakening and anxiety of the parent was present in 80.5%, 41.2%, 46.8% and 57% of the children, respectively. After adjustment of therapy regimens at Visit 1, mainly by adding a leukotriene receptor antagonist, asthma control was reported to be much better in 53.4% of the children at Visit 2.

Conclusions: As asthma control is inadequately achieved within a major portion of asthmatic children, it is imperative to find measures to improve asthma control and hence, to reduce the burden of disease.     

纳米材料在止血方面的研究进展

纳米材料因其独特的微观结构优势,已被广泛应用于材料制备、微电子与计算机技术、医学与健康、环境与能源等领域。与传统止血材料相比,纳米材料在一定程度上能提高传统止血药物的生物利用度和稳定性,增强药物的缓控与靶向释放,为现代化新型止血材料的发展奠定了良好的基础。对脂质体、纳米粒、自组装纳米肽、纳米纤维等多种纳米止血材料的前沿设计和应用进展进行了综述,最后简述纳米止血材料存在的问题和发展前景。     

药物非临床毒代动力学研究进展

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