乌头碱对培养新生大鼠心室肌细胞Connexin43蛋白磷酸化的影响

目的建立细胞水平的染毒模型,观察乌头碱对心肌细胞缝隙连接蛋白Connexin43(Cx43)的影响。方法实验分0.25、0.5、0.75、1.0、1.5和2.0μmol/L等6个不同浓度乌头碱染毒组,运用蛋白印迹法和免疫荧光技术,检测各组及对照组心肌细胞Cx43蛋白磷酸化状态的改变。结果蛋白印迹检测显示,不同浓度染毒组心肌细胞中Cx43蛋白总量与正常对照组无显著差异;0.5μmol/L乌头碱染毒后,Cx43开始出现脱磷酸化;当染毒浓度达到1.0μmol/L后,Cx43脱磷酸化显著,且1.5及2.0μmol/L染毒效果和1.0μmol/L染毒组相当。免疫荧光分析结果提示乌头碱作用后,心肌细胞Cx43蛋白在羧基端第368位点丝氨酸残基(Ser368)发生明显的脱磷酸化。结论一定浓度的乌头碱能诱导心肌细胞缝隙连接蛋白Cx43发生显著脱磷酸化。     

A light stabilizer Tinuvin 770-induced toxic injury of adult rat cardiac myocytes

Tinuvin 770/bis(2,2,6,6-tetramethyl-4-piperidinyl)sebacate is a worldwide used light stabilizer for plastic materials like polyolefins. Tinuvin 770 is a biologically active component of polypropylene tubes. Glossmann and his study group managed to extract this compound by aqueous or organic solvents from laboratory plastic tubes, and propose that Tinuvin 770 is a potent blocker of L-type Ca(2+)-channel through the phenylalkylamine and benzothiazepine-selective drug binding domains of the alpha(1) subunit of the receptor [Proc. Natl. Acad. Sci. U.S.A. 90 (1993) 9523].We examined the direct morphological effect of Tinuvin 770 in give 25nmol, 0, 30, 60, 120 minute exposure time in isolated cardiomyocytes from adult rats. Incubation of myocytes with Tinuvin resulted in a progressive decline of rod-shaped and viable cells. It was accompanied by an increase in number of hypercontracted myocytes with microbleb formation compared to control and depletion of ATP level.In summary, our results demonstrate that plasma membrane damage and hypercontraction are manifestations of Tinuvin-induced injury of isolated cardiomyocytes.     

甲基苯丙胺对大鼠认知和脑电图的影响

目的研究甲基苯丙胺（methamphetamine,MA）对脑功能的影响机制,实验设计观察慢性反复使用MA是否同时对大鼠认知行为和脑电活动产生影响。方法 14只雄性SD大鼠（180～200g）随机分为生理盐水注射组（对照组）和MA注射组（实验组5mg/kg体重）每天一次腹腔注射。连续注射7d后进行被动避暗回避行为测试和脑电图检测。结果与对照组相比,实验组大鼠表现为被动避暗回避行为的潜伏期延长,脑电图频谱分析显示δ波相对功率值减小,β波相对功率值增大,差异有统计学意义（P〈0.05）。结论慢性反复使用MA对大鼠被动回避行为和脑电活动均有影响,说明MA滥用造成的认知行为改变与中枢神经系统电生理活性改变有关。     

CI-mass fragmentographic analysis of methamphetamine and amphetamine in human autopsy tissues after acute methamphetamine poisoning

A 22-year-old male methamphetamine abuser was put under police protection owing to his abnormal state of excitation, but died 1 h later. Distribution of methamphetamine and amphetamine in the body was analyzed by the chemical ionization mass fragmentographic method. Amphetamine/methamphetamine concentrations (μmol/100 g) were $\text{0.24}\text{5.59}$ in blood, $\text{0.41}\text{9.43}$ in liver, $\text{0.41}\text{10.02}$ in brain, $\text{0.37}\text{9.80}$ in kidney, $\text{0.18}\text{4.57}$ in muscle, $\text{0.02}\text{0.63}$ in subcutaneous fat and $\text{1.87}\text{1464}$ in gastric contents. Total amount of methamphetamine hydrochloride in stomach contents was about 54 mg. Amphetamine concentrations in tissues ranged from 3.2% to 4.3% of methamphetamine, and was 0.1% in stomach contents. Amphetamine in tissues seems to be a metabolite of methamphetamine, and amphetamine in gastric contents is presumed to result from gastric mucous excretion. The blood concentration of methamphetamine was at a fatal level, and the total amount of the drug in gastric contents indicates that fatal poisoning occurred by ingestion.     

Immunofluorescence demonstration of digoxin in human myocardial tissue and isolated rat cardiac myocytes with monoclonal antibodies

The aim of the present investigation was to identify the morphological correlates of digoxin binding sites in human heart muscle tissue and isolated viable rat heart myocytes. Cardiac glycoside linked to myocardial cells was demonstrated by monoclonal digoxin specific antibody and by FITC-conjugated anti-mouse immunoglobin serum. This versatile immunofluorescence method can be used in diagnostic and experimental studies of cardiac glycoside binding.     

生物检材中甲基苯丙胺及苯丙胺的分析研究进展

对近几年国内外22篇有关生物检材中甲基苯丙胺及苯丙胺测定的文献进行了综述。介绍了血、尿、毛发等生物检材的收集与预处理方法,比较了生物检材中甲基苯丙胺及苯丙胺的液-液萃取(LLE)、固相萃取(SPE)、固相微萃取(SPME)和顶空固相微萃取(HS-SPME)等提取方法,以及内标的选取、不同的衍生化方法和包括免疫、GC/MS、GC/NPD、GC/ECD、GC/FID、HPLC、HPCE在内的各种检测方法。最后,对分析结果的评定进行了讨论。     

甲基苯丙胺和氯胺酮在家兔体内毒代动力学及相互影响

目的比较家兔单独静脉注射甲基苯丙胺、氯胺酮及二种药物联合静注时的毒物代谢动力学过程,评价二种药物毒代动力学的相互作用。方法单用甲基苯丙胺组以3mg/kg剂量家兔静脉注射甲基苯丙胺,单用氯胺酮组以30mg/kg剂量家兔静脉注射氯胺酮,合用组以相同剂量同时注射两种药物。分别于给药后不同时间点收集血浆标本,测定各时间点药物浓度,WinNonLin软件拟合毒代动力学房室模型并计算参数。结果甲基苯丙胺在家兔体内的毒代动力学过程呈一级动力学特征,符合单室模型,合用氯胺酮后不改变其模型类型。氯胺酮在家兔体内的毒代动力学过程呈一级动力学特征,符合单室模型,合用甲基苯丙胺后符合二室模型。结论甲基苯丙胺和氯胺酮可以相互延缓其在体内的消除过程,增加彼此在体内的吸收,从而延长作用时间。     

Enantiomeric separation of methamphetamine and related analogs by capillary zone electrophoresis: intelligence study in routine methamphetamine seizures

A method for simultaneous enantiomeric separation of ephedrine, pseudoephedrine, and methamphetamine (MA) in a single run by simple capillary zone electrophoresis (CZE) with beta-cyclodextrin as a chiral selector is described. The effects of the buffer pH, phosphate concentration, beta-cyclodextrin concentration, voltage and temperature on the peak resolution were examined. Good enantiomeric resolution was attained for each analyte under our optimized conditions: 15 mM beta-cyclodextrin, 300 mM NaH2PO4 at pH 2.5 with an uncoated capillary (64.5 cm x 50 microm), applied potential at 20 kV and temperature at 30 degrees C. Ultraviolet (UV) detection at a fixed wavelength (200 nm) was employed using a diode array detector. Using phentermine as an internal standard, migration times for all analytes are reproducible within 0.16% for intra-day and 0.6% for inter-day runs. Application of this method to the analysis of confiscated drugs is discussed.     

A study of the metabolism of methamphetamine and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in isolated rat hepatocytes

The metabolism of methamphetamine (MA) and 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in freshly isolated rat hepatocytes was investigated, and compared with in vivo results. A suspended hepatocyte culture, established from male Wistar rats using a collagenase perfusion technique, was incubated in the presence of MA or 2C-B. After enzymatic hydrolysis of the conjugated forms, the metabolites were extracted by liquid-liquid partition and analyzed by gas chromatography/mass spectrometry (GC/MS). Amphetamine, p-hydroxymethamphetamine and p-hydroxyamphetamine were detected in the culture fluids of the rat hepatocytes inoculated with MA. The alcohol derivative, carboxylic acid derivative, 2-O-desmethyl-2C-B, 2-O-desmethyl-N-acetyl-2C-B and 5-O-desmethyl-N-acetyl-2C-B were detected in the case of 2C-B. The major metabolite of MA in rat hepatocytes was p-hydroxymethamphetamine. This is in good agreement with the urinary excretion profile for rats that were fed MA. 2-O-Desmethyl-2C-B and the carboxylic acid derivative were the major recovered metabolites of 2C-B in the rat hepatocyte culture, a slight deviation from the in vivo findings, in which 5-O-desmethyl-N-acetyl-2C-B was found to be the main component. Metabolites with a hydroxy group were largely present in their conjugated forms in the culture fluids, except for 2-O-desmethyl-2C-B. Taking these results into consideration, a primary hepatocyte culture system has the potential to provide a quick and handy method for estimating the in vivo metabolic fate of abused drugs.     

生物检材中甲基苯丙胺分析方法研究进展

甲基苯丙胺(MAM)是国内、外药物滥用最为广泛且因此,发展快速、准确的MAM检测方法对法医学研究、打击犯罪等方面都有重要的意义。本文对近年来国内外有关在生物检材中进行甲基苯丙胺测定的薄层色谱法、气相色谱法、高效液相色谱法、毛细管电泳法、免疫分析法等方法进行了归纳和综述,并提出了甲基苯丙胺分析方法的发展方向。     

小鼠各脏器及血中甲基苯丙胺的分布

目的通过给小鼠腹腔注射甲基苯丙胺(MAMP),建立小鼠急性染毒模型。方法运用GC/NPD技术,系统地进行了染毒小鼠模型各脏器及血中甲基苯丙胺(MAMP)的定性定量测定。采用1-萘胺作为内标,样品处理时采取加盐酸成盐后,又碱化,用有机溶剂萃取浓缩挥发。结果回收率高于80%。血、各脏器中最低检出限为2～5ng/ml。结论脑、肾、脾组织可以用于法庭科学分析。     

The effects of marital status on adult female homicides in the United States

With data from the 1992 Mortality Detail File, we examine the effects of marital status on female homicide victimization in the United States. Multivariate logistic regression was fitted to all female homicide deaths occuring in 1992. Results indicate that, controlling for race, education, nativity, city size, region of the country, occupation, age, day of the week, and month of the year, divorced females were 55.3% more likely to be homicide victims than married females. Notably, single women did not differ from married women with respect to homicide risk. Finally, widowed women were significantly less likely to be homicide victims than married women. The results suggest a complicated relationship between marital status and female homicide victimization.     

血,尿中甲基苯丙胺以及代谢产物苯丙胺的分析研究

介绍了血、尿中甲基苯丙胺及其代谢产物苯丙胺的GC/MS，GC/FID和GC/NPD的定性定量分析方法．样品以4-苯基丁胺为内标，用200μl环己烷直接提取进样或提出物经微波照射快速衍生化后分析．方法简便、快速，回收率高于80％．检出限为2～5ng/ml．建立了体内甲基苯丙胶和苯丙胺的d/l光学对映体测定方法，可用于判断毒品来源及毒作用．     

大鼠皮质神经细胞缺氧缺糖损伤后MAP-2表达变化规律

目的观察原代培养大鼠大脑皮质神经细胞缺氧缺糖（OGD）损伤24h内的形态学及微管相关蛋白2（MAP-2）表达变化。方法使用出生1-2d的Wistar大鼠,取大脑皮质神经细胞进行原代培养,用连二亚硫酸钠加低糖培养基制作神经细胞OGD损伤模型,损伤后应用倒置显微镜观察形态学变化,Western印迹法观察MAP-2蛋白表达变化。结果原代培养大鼠大脑皮质神经细胞OGD损伤后1h,少数神经细胞突起缩短;伤后6-12h神经细胞胞体明显皱缩,多数细胞突起缩短或消失;伤后24h神经细胞形态部分恢复,部分突起重新出现。Western印迹法显示,MAP-2在神经细胞OGD损伤后1h表达降低,伤后12h达低谷,24h表达升高。结论 OGD损伤后,原代培养大鼠大脑皮质神经细胞的形态及MAP-2表达随时间呈现一定的规律性变化。     

Oxygen-Glucose deprivation-induced dynamic changes of MAP-2 in cultured rat cortical neuronsCSCD

Objective: To study the expression of microtubule-associated protein-2 (MAP-2) and morphological changes of cultured rat cortical neurons after oxygen-glucose deprivation (OGD) injury. Methods: Cortical neurons were isolated from P1 ∼ 2 neonatal Wistar rat cerebral cortices and cultured in OGD medium. MAP-2 expression and morphological changes of the cultured neurons were investigated by Western Blotting and under inverted microscope. Results: Without OGD injury, the cultured neuron had round or elliptical cell body with long intact dendrites. The neurons remained round with short dendrites at 1h post-OGD, while wrinkled with few dendrites at 6h and 12h post-OGD; the neurons partly recovered and some dendrites reappeared at 24h post-OGD. Western Blotting showed MAP-2 protein decreased 1h post-OGD, reached the minimal level at 12h, and then increased at 24h post-OGD. There was no significant difference between MAP-2 expressed at 6h post-OGD and 12h post-OGD. Conclusion: After moderate OGD injury, cultured rat cortical neurons demonstrate time-dependent MAP-2 expression and morphological changes.     

High-throughput sequencing to evaluate the effects of methamphetamine on the succession of the bacterial community to estimate the postmortem interval

In forensic medical examinations, estimating the postmortem interval (PMI) is an important factor. Methamphetamine (MA) is a synthetic stimulant that is commonly abused, and estimation of the PMI after MA abuse has become one of the main tasks in forensic investigation. Microorganisms play a vital role in carrion decomposition. Analysing the bacterial succession patterns can be used as a forensic tool to estimate the PMI. The present study aimed to analyse bacterial succession changes during the decomposition of MA to estimate the PMI. We analysed bacterial communities in rabbits treated with three different concentrations of MA (0, 22.5, and 90 mg/kg) under the natural conditions of 20 °C and 70% humidity by sequencing 16S rRNA gene amplicons using the Illumina MiSeq system. We obtained 2 374 209 high-quality sequences and 2 937 operational taxonomic units (OTUs). The relative abundances of the bacterial communities varied markedly in response to different MA concentrations. Interestingly, in response to the different concentrations of MA, Bacteroidetes became disparate in the rectum in the late PMI. Increased numbers of bacterial taxa were identified in the rectum and buccal cavity samples, except at the highest concentration of MA in the rectum samples when PMI was 0–h, than were present in live rabbits. Meanwhile, the PMI correlated significantly with bacterial succession at different taxonomic levels. Our results suggested that bacterial community succession could be used as a “microbial clock” to estimate the PMI in cases of MA-related death; however, further study is required to gain a deeper understanding of this concept.     

甲基苯丙胺和乙醇在染毒大鼠体内联用的实验研究

目的研究甲基苯丙胺（MA）和乙醇联合应用在急性、亚急性染毒大鼠体内的情况。方法以MA1.0 mg/kg剂量对慢性自由饮酒大鼠多次腹腔注射,分别建立急性、亚急性染毒大鼠模型;处死后即时检测血中乙醇浓度、体液和组织样品中MA的浓度。结果多次注入MA药后,亚急性中毒大鼠体内的MA浓度高于急性中毒大鼠;急性和亚急性联合中毒大鼠体内MA浓度均高于急性和亚急性单一药物组。结论无论是否联用乙醇,14d内增加注射次数会在大鼠体内产生不同程度的MA残留;与乙醇联用可加速MA在大鼠体内的吸收,其药物浓度的升高程度随生物样品不同存在差异。     

The effects of sarin-like and soman-like organophosphorus agents on MAPK and JNK in rat brains

One sarin-like and one soman-like organophosphorus agent [bis(isopropyl methyl)phosphonate, BIMP and bis(pinacolyl methyl)phosphonate, BPMP] were injected intravenously (iv) in rats. An increase in the tyrosine phosphorylation of several proteins in the cytosol fraction of the brain was observed. Activation of c-Jun N-terminal kinase (JNK) and slight activation of mitogen-activated protein kinase (MAPK) in the cytosol were also observed. The activation of these enzymes may be related to the high toxicity of these nerve agents.     

毛发中甲基苯丙胺及代谢产物苯丙胺的分析研究

介绍了毛发中甲基苯丙胺（ MAMP）及代谢产物苯丙胺（ AMP）的 GC/NPD、 GC/MS的定性定量分析方法。毛发用 0.1 mol/L HCl水解, 4－苯基丁胺（ 4－ PBA）为内标,液－液提取,三氟乙酸酐（ TFA）衍生化。毛发用量为 10mg,检出限为 GC/NPD 0.5ng/mg, GC/MS 0.1ng/mg,回收率大于 78％。该方法成功应用于染毒豚鼠毛发中 MAMP及其代谢产物 AMP浓度变化过程的测定。     

Comparison of extraction methods for methamphetamine and its metabolites in tissue

Five extraction methods were examined for analysis of methamphetamine and its major metabolites in tissue samples. The extraction methods studied were an acetone extraction method, an ethanol extraction method, an ammonium sulfate method, dialysis, and a direct solvent extraction. Acetone, ethanol, and dialysis methods showed no interference from endogenous components using thin-layer chromatography and gas chromatography, and gave satisfactory recovery of methamphetamine, amphetamine, and p-hydroxymethamphetamine when added to rabbit liver. These methods, however, proved time-consuming. The ammonium sulfate method and direct solvent extraction method were simple and more rapid, but recovery of the polar metabolite was poor.