克拉霉素对糖氧剥离大鼠皮质神经细胞的保护作用及其抑制凋亡的机制研究

目的：研究克拉霉素对大鼠皮质神经细胞糖氧剥离（OGD）后的保护作用及其与抑制凋亡相关的作用机制。方法：提取培养原代大鼠皮质神经细胞,建立皮质神经细胞糖氧剥离模型,OGD前予以克拉霉素（CAM）预处理;通过存活/凋亡检测试剂盒于荧光显微镜下观察各组细胞凋亡情况;LDH试剂盒测定各组培养基LDH含量定量评估细胞凋亡情况;蛋白免疫印迹法测定各组细胞Caspase-3,Bax,Bcl-2的表达情况。结果：OGD处理后皮质神经细胞凋亡及乳酸释放含量较正常组明显增加,差异具有显著统计学意义（76.51±14.92% VS 15.37±3.91%,p＜0.01）,100μM CAM预处理可显著减少OGD造成的细胞凋亡及LDH释放（21.64±7.16% VS 76.51±14.92%,p＜0.01）;OGD处理后皮质神经细胞Caspase-3,Bax/Bcl-2表达显著升高,与Control组相比,均具有显著统计学意义（p＜0.01）,而CAM预处理有效降低了Caspase-3,Bax/Bcl-2表达。结论：克拉霉素对糖氧剥离大鼠皮质神经细胞具有保护作用,其作用可能与促进了Caspase-3,Bax上调,Bcl-2蛋白下调的凋亡相关通路有关。     

rhIGF-1对神经细胞缺血再灌注损伤的保护作用

目的：研究重组人胰岛素样生长因子1（rhIGF-1）对缺血再灌注所致神经细胞损伤的保护作用。方法：自新生大鼠脑组织中分离培养原代神经细胞,^3H—TdR掺入法检测rhIGF-1对神经细胞增殖的影响。将所培养的细胞分为正常对照组、类缺血对照组及损伤后rhIGF-1干预组，对不同组别的细胞进行类缺血-复氧处理，流式细胞检测细胞凋亡情况。结果：rhIGF-1可明显促进原代培养的神经细胞增殖，并降低再灌注损伤所导致的细胞凋亡。结论：rhIGF-1对神经细胞缺血再灌注损伤具有保护及治疗作用。     

黄连解毒汤有效部位对培养大鼠皮层神经元缺糖缺氧损伤的保护作用

目的　观察黄连解毒汤有效部位 (HLJDTAF)对缺糖 /缺氧培养所致大鼠皮层神经细胞损伤的保护作用。方法　体外培养大鼠皮层神经细胞 ,以缺氧加缺糖培养建立神经细胞“缺血”性损伤模型 ,观察HLJDTAF对培养神经细胞“缺血”性损伤的保护作用。结果　HLJDTAF 6 10mg·kg-1能明显增高模型细胞的活性 ;30 5mg·kg-1能显著降低模型细胞乳酸脱氢酶 (LDH)漏出率 ;6 10、30 5、15 3mg·kg-1明显降低上清液中NO含量 ,降低裂解液中MDA含量 ,提高SOD活性。结论　HLJDTAF对正常细胞无明显影响 ,对培养神经细胞“缺血”性损伤具有显著的保护作用 ,其机制可能与其降低NO含量、抗过氧化作用有关     

银杏叶提取物对谷氨酸诱导神经细胞损伤的作用研究

目的：探究银杏叶提取物（EGb）对谷氨酸诱导体外培养神经细胞损伤的保护作用及相关机制,为EGb应用于缺血性卒中提供依据。方法：取孕15～18天SD胎鼠的皮层神经细胞进行原代培养（对照组）,在此基础上,建立谷氨酸诱导神经细胞损伤模型（Glu组）。向Glu组中预先加入4种不同浓度（12．5～100mg·L^-1）EGb作用（研究组）。通过测定神经细胞NO及LDH的释放量来反映神经细胞损伤程度。结果：谷氨酸呈浓度依赖性升高神经细胞NO及LDH释放量;与Glu组相比较,EGb（12．5～100mg·L^-1）能不同程度的抑制NO、LDI-I释放,且EGb浓度为50mg·L^-1时作用最显著（P〈0．01）。结论：谷氨酸通过NO诱导神经细胞损伤,EGb通过抑制NO、LDH释放实现拮抗谷氨酸神经细胞毒性作用。     

栝楼桂枝汤对氧糖剥夺损伤皮层脑片的神经保护作用

目的 观察栝楼桂枝汤对氧糖剥夺损伤皮层脑片的神经保护作用.方法 将培养t4d的皮层脑片行氧糖剥夺损伤45min后,药物干预3d,采用碘化丙啶(PI)染色法检测皮层脑片损伤程度,微量酶标法检测脑片培养液上清中LDH的释放量.结果 与空白对照组比较,模型对照组PI荧光强度、LDH释放量明显升高,栝楼桂枝汤干预后,PI荧光强度、LDH释放量明显减少,呈剂量依赖性.结论 栝楼桂枝汤对皮层脑片氧糖剥夺后的神经损伤具有较好的保护作用.     

阿米替林对谷氨酸损伤中枢神经细胞的保护作用

目的：研究阿米替林（Ami)对谷氨酸损伤培养大鼠皮层神经细胞的保护作用。方法：分离培养15－18d胎龄的大鼠神经细胞，加入谷氨酸（Glu)，造成神经细胞的损伤，测定乳酸脱氢酶，一氧化氮，丙二醛及超氧化物歧化酶的含量，观察谷氨酸对神经细胞的损伤作用及阿米替林的保护作用。结果：加入谷氨酸后，神经细胞出现明显损伤性变化，死亡率升高，培养上清液中乳酸脱氢酶（LDH），一氧化氮（NO）含量增加，细胞匀浆中丙二醛（MDA）生成增加，超氧化物歧化酶（SOD）含量明显减少，Ami10^-8-10^-6mol/L^-1能不同程度地减轻上述损伤性变化。结论：Ami对谷氨酸所致的神经细胞损伤具有保护作用。其作用机制可能与抗脂质过氧化作用有关。     

淫羊藿苷对血管紧张素Ⅱ诱导人脐静脉内皮细胞损伤的保护作用

探讨淫羊藿苷对血管紧张素Ⅱ（AngⅡ）诱导损伤人脐静脉内皮细胞株（ECV-304）的影响。培养内皮细胞，淫羊藿苷作用24h后，采用AngII诱导制备内皮细胞损伤模型，测定细胞存活率（MTT法）、培养液中乳酸脱氢酶（LDH）释放量、NO值、清除超氧阴离子自由基（O2^-）和羟自由基（·OH）的能力，测定胞内超氧化物歧化酶（SOD）活性、T-NOS、iNOS以及eNOS的含量。与AngⅡ单独处理组相比，淫羊藿苷能明显提高细胞存活率，提高SOD、T-NOS和cNOS活力，提高NO含量，增强清除O2^-和·OH的能力，降低LDH和iNOS的量。结果表明淫羊藿苷对AngⅡ损伤的内皮细胞有一定的保护作用。     

银杏叶提取物对缺氧复氧诱导的大鼠皮层神经元凋亡和Bcl-2蛋白表达的影响

目的 观察银杏叶提取物（EGb）及其活性成份银杏总内酯（Gin）对缺氧复氧诱导的大鼠皮层神经元凋亡的保护作用。方法 选用胎龄14～16d的SD胎鼠的大脑皮层细胞进行原代培养,建立缺氧复氧（H／R）神经元损伤模型。实验分为正常组、缺氧复氧（H／R）组、药物实验（EGb、Gjn）组、阳性对照（MK-801）组。应用MTF、TUNEL及Western blot方法。结果 EGb和Gin均能提高皮层神经元缺氧复氧后的存活率,EGb和Gin组神经元的凋亡率低于H／R组且Bcl-2蛋白表达量较H／R组升高。结论 EGb和Gin可部分拮抗缺氧复氧条件下体外培养的皮层神经元的凋亡,该保护作用与其诱导Bcl-2蛋白表达有关。     

芍药内酯苷对高糖诱导的人脐静脉内皮细胞损伤的保护作用

目的 研究芍药内酯苷对高糖损伤的人脐静脉内皮细胞（HUVECs）的保护作用及机制.方法 采用33mmol·L-1的高糖培养基建立HUVECs损伤模型,并在造模前给予不同浓度的芍药内酯苷进行预保护,采用MTT法检测细胞活力,流式细胞术检测细胞凋亡,采用试剂盒检测细胞中内源性一氧化氮合酶（eNOS）和半胱天冬酶-3（Caspase-3）活性以及培养液中一氧化氮（NO）和乳酸脱氢酶（LDH）含量.结果 芍药内酯苷能够剂量依赖性增强细胞活力,降低Caspase-3活性和细胞凋亡率（P＜0.05）,并能增强eNOS的活性和NO的释放量（P＜0.05）.结论 芍药内酯苷对高糖诱导的HUVEs损伤具有保护作用,其机制可能与促进eNOS活性提高、NO释放量增加和抑制Caspase-3活性有关.     

左旋丁基苯酞对低糖氧造成神经元损伤的保护作用

目的探讨新药左旋丁基苯酞（1-NBP）对低糖低氧造成的神经细胞坏死和凋亡的保护作用，并从线粒体和细胞内钙角度对其可能的作用机制进行研究。方法：以低糖低氧造成原代培养神经细胞的损伤模型，采用Hoeehest 33824（Hoe）、Ppropidium iodide（PI）、Fluo-3／AM和Rhodamine-123（Rhod）对细胞进行荧光染色，分别测定不同损伤条件下神经细胞的坏死、凋亡、细胞内游离钙和线粒体膜电位的变化，并对1-NBP的保护作用进行观测。结果原代培养神经元的的坏死和凋亡的发生率在低糖氧处理3h后即出现明显升高，     

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.     

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.     

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     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

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.     

Tramadol concentrations in blood and in cerebrospinal fluid in a neonate

Based on blood and cerebrospinal fluid samples collected in a full-term neonate, the penetration of tramadol in the central nervous system is described. Following intravenous administration of tramadol, a lag time of about 4 h was observed until full blood–brain equilibration was achieved. This pharmacokinetic observation is in line with a recent pharmacodynamic evaluation of the central opioid effects of tramadol in adults.     

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.