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41.
The effectiveness of decontamination procedures used for the removal of external drug contamination in forensic hair analysis is an ongoing debate. This investigation evaluated wash methods complying with Society of Hair Testing (SoHT) guidelines and their capacity to remove cocaine (COC) and methamphetamine (MA) from artificially contaminated hair. The most effective decontamination method was determined using a systematic approach, involving (1) an initial washing solvent screen, (2) optimization of wash duration, (3) comparison of sequential wash methods, and (4) reanalysis of clinical hair samples. For analysis, hair was subjected to micro‐pulverized methanolic extraction prior to quantitation by ultra‐high performance liquid chromatography?tandem mass spectrometry (UHPLC?MS/MS). Methanol (MeOH) and 0.1 M phosphate buffer (pH 6) were the most effective organic and aqueous solvents, respectively, removing 28%–38% of COC and 16%–31% of MA. Wash durations longer than 30–60 minutes did not remove additional amounts, and a more efficient sequential wash method was subsequently developed. Despite this, the interpretation of reportable results relative to the SoHT cut‐off levels was unchanged for most clinical hair samples reanalyzed after washing by agitation for 30 minutes with MeOH. These findings highlight the inability of decontamination solvents to completely remove external COC and MA contamination from hair, including wash methods adhering to SoHT guidelines.  相似文献   
42.
噻诺啡对小鼠甲基苯丙胺行为敏化的影响   总被引:1,自引:0,他引:1  
目的:探讨新型阿片受体部分激动剂-噻诺啡对小鼠甲基苯丙胺行为敏化过程的影响。方法:测定小鼠的自主活动,观察噻诺啡对小鼠的自主活动及急性甲基苯丙胺处理所致小鼠活动增强效应的影响。小鼠腹泻注射甲基苯丙胺2mg·kg~(-1)·d~(-1),连续7d,建立甲基苯丙胺诱导的小鼠行为敏化模型,观察噻诺啡对小鼠行为敏化的影响。结果:单次皮下注射噻诺啡(0.0625~1.0mg·kg~(-1))可剂量依赖性地抑制小鼠的自主活动(P<0.05),连续给药7d,噻诺啡对小鼠自主活动的抑制作用不产生敏化,而耐受。噻诺啡对急性甲基苯丙胺处理所致小鼠的高活动性无明显影响。噻诺啡对甲基苯丙胺诱导的小鼠行为敏化的形成和表达无显著作用,但可剂量依赖性地抑制敏化的转化(P<0.05或P<0.01)。结论:噻诺啡对中枢神经系统具有抑制作用,并且可以阻止甲基苯丙胺诱导小鼠产生行为敏化的转化过程,提示噻诺啡可能对甲基苯丙胺的成瘾行为具有一定的干预作用。  相似文献   
43.
归元片对小鼠甲基苯丙胺行为敏化的影响   总被引:3,自引:0,他引:3  
目的:探讨中药复方制剂归元片对甲基苯丙胺行为敏化的影响.方法:测定小鼠的自主活动,观察归元片对小鼠自主活动及甲基苯丙胺急性活动增强效应的影响.小鼠慢性甲基苯丙胺处理,建立甲基苯丙胺诱导的行为敏化小鼠模型,观察归元片对甲基苯丙胺行为敏化获得和表达的影响.结果:归元片呈剂量依赖性降低小鼠的活动性,对甲基苯丙胺的急性高活动效应有抑制作用.归元片阻断小鼠甲基苯丙胺行为敏化的获得和表达.结论:归元片对中枢神经系统功能具有抑制作用,能抑制甲基苯丙胺行为敏化的获得和表达,提示归元片能抑制甲基苯丙胺的奖赏效应,可能对防治甲基苯丙胺的滥用和成瘾有效.  相似文献   
44.
The analysis of organic impurities plays an important role in the impurity profiling of methamphetamine, which in turn provides valuable information about methamphetamine manufacturing, in particular its synthetic route, chemicals, and precursors used. Ultra‐high‐performance liquid chromatography – tandem mass spectrometry (UHPLC – MS/MS) is ideally suited for this purpose due to its excellent sensitivity, selectivity, and wide linear range in multiple reaction monitoring (MRM) mode. In this study, a dilute‐and‐shoot UHPLC – MS/MS method was developed for the simultaneous identification and quantitation of 23 organic manufacturing impurities in illicit methamphetamine. The developed method was validated in terms of stability, limit of detection (LOD), lower limit of quantification (LLOQ), accuracy, and precision. More than 100 illicitly prepared methamphetamine samples were analyzed. Due to its ability to detect ephedrine/pseudoephedrine and its high sensitivity for critical target markers (eg, chloro‐pseudoephedrine, N‐cyclohexylamphetamine, and compounds B and P), more impurities and precursor/pre‐precursors were identified and quantified versus the current procedure by gas chromatography – mass spectrometry (GC – MS). Consequently, more samples could be classified by their synthetic routes. However, the UHPLC – MS/MS method has difficulty in detecting neutral and untargeted emerging manufacturing impurities and can therefore only serve as a complement to the current method. Despite this deficiency, the quantitative information acquired by the presented UHPLC – MS/MS methodology increased the sample discrimination power, thereby enhancing the capacity of methamphetamine profiling program (MPP) to conduct sample‐sample comparisons.  相似文献   
45.
Introduction and Aims. Cigarette smoking occurs frequently among individuals with methamphetamine (MA) dependence. Preclinical and clinical evidence has suggested that the common co‐abuse of MA and cigarettes represents a pharmacologically meaningful pattern. Methods. The present study is a secondary analysis of a randomised, placebo‐controlled trial of bupropion treatment for MA dependence (bupropion n = 36; placebo n = 37). A hierarchical logistic modelling approach assessed the efficacy of bupropion for reducing MA use separately among smokers and non‐smokers. Among smokers, relations between cigarettes smoked and MA use were assessed. Results. Smoking status did not affect treatment responsiveness in either the bupropion condition or the placebo condition. In the placebo condition, increased cigarette use was associated with an increased probability of MA use during the same time period. This effect was not observed in the bupropion condition. Discussion and Conclusions. Initial smoking status did not impact treatment outcomes. Among smokers, results suggest that bupropion may dissociate cigarette and MA use. The effect was modest and a precise pharmacological mechanism remains elusive. Cholinergic systems may be relevant for MA use outcomes. Future studies should continue to assess the role of smoking in MA treatment outcomes.[Brensilver M, Heinzerling KG, Swanson A‐N, Telesca D, Furst BA, Shoptaw SJ. Cigarette smoking as a target for potentiating outcomes for methamphetamine abuse treatment. Drug Alcohol Rev 2013;32:96–99]  相似文献   
46.
OBJECTIVE: To describe the use of crystal methamphetamine hydrochloride "ice," a powerful, synthetic stimulant drug associated with rapid weight loss. METHOD: We report the first three cases of young women "ice" users requiring admission to a specialized eating disorders unit. RESULTS: Case one had no prior history of an eating disorder and became emaciated following regular use of "ice"; she regarded weight gain positively. Case 2 had polysubstance abuse since early adolescence and commenced binge eating and vomiting in response to weight gain when not using "ice"; she learned to maintain her weight without weight losing behaviors. Case 3 developed anorexia nervosa in early adolescence, required numerous inpatient admissions and commenced using stimulant drugs for weight loss in her late teens; she discharged prematurely. All patients had features of personality disorder on interview and drug abuse had impaired their work and social adjustment. DISCUSSION: "Ice" use may be associated with the onset of disordered eating or used as an efficient weight losing behavior in an established eating disorder.  相似文献   
47.
目的:探讨经皮穴位电刺激对气郁质甲基苯丙胺依赖者戒断后焦虑抑郁情绪及心理渴求的影响.方法:将70例受试者随机分为治疗组和对照组,各35例.治疗组予经皮穴位电刺激治疗,对照组予模拟经皮穴位电刺激治疗,刺激的穴位均相同.采用汉密尔顿抑郁量表(HAMD)、汉密尔顿焦虑量表(HAMA)、视觉模拟评分(VAS)评估患者治疗前及治...  相似文献   
48.

Objectives

Curcumin, a major active component of Curcuma longa, possesses antidepressant effects that are mediated by the 5-HT system. However, little is known about the effect of curcumin on the behavioral consequences of methamphetamine (METH).

Methods

The subjects were male, adult Sprague-Dawley rats. In Experiment 1, the effects of 20 and 40 mg/kg curcumin (i.p.) on response rates and breakpoints of 0.06 mg/kg/infusion METH were evaluated. In Experiment 2, rats were self-administering METH for 10 days followed by a 14-day abstinence period. During the abstinence period, the animals were treated with DMSO, 20 or 40 mg/kg curcumin. All rats were then tested for extinction responding and cue-induced reinstatement. In Experiment 3, rats were treated with DMSO, 20, or 40 mg/kg curcumin15 min before a METH-induced locomotor activity test for 14 consecutive days. In Experiment 4, rats were pretreated with DMSO or curcumin (20 mg/kg or 40 mg/kg) for 13 days and were subsequently tested for METH-induced locomotor activity on the 14th day. In Experiment 5, three groups were tested for locomotor activity after an injection of DMSO, 20, or 40 mg/kg curcumin. The test was repeated for 14 days.

Results

Curcumin produced little effect on response rates and breakpoints maintained by METH. Chronic treatment of only 40 mg/kg curcumin during the abstinence phase enhanced cue-induced reinstatement of METH self-administration. Chronic administration of curcumin increased METH-induced sensitization of locomotor activity at the lower (20 mg/kg) but not higher (40 mg/kg) dose. However pretreatment of curcumin alone showed no significant effect on acute locomotor responses to METH and locomotor responses per se.

Conclusions

Curcumin enhanced, rather than inhibited the behavioral effects of METH.  相似文献   
49.
Abstract

There are no studies of African Americans', methamphetamine use in the South where it is widespread among whites. We describe factors that inhibit or facilitate the diffusion of methamphetamine use among African Americans based on qualitative interviews with 86 drug users in rural Arkansas and Kentucky. Results suggest low prevalence of methamphetamine use among African Americans, and interviewees cited several barriers to its diffusion which were linked to the drug's ingredients, psychoactive and physiological effects, difficulty in accessing distribution networks, and established African-American preference for cocaine. Fourteen African Americans reported methamphetamine use and discussed pathways to it. Possible increases in African-American methamphetamine use merits further investigation.  相似文献   
50.
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