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31.
For several years, the misuse of stimulant substances is increasingly observed both in the field of sport, to improve the functions of the body and therefore to be more performant, and also by non-athletes to make life more tolerable on a daily basis. Adrafinil, 2-((diphenylmethyl)sulfinyl)-N-hydroxyacetamide, is a drug designed for the treatment of narcolepsy by promoting an awakened state, and to treat alertness and neurological symptoms in the elderly. It is primarily metabolized in vivo to an active form, i.e. modafinil, 2-((diphenylmethyl)sulfinyl)acetamide. The World Anti-Doping Agency (WADA) banned these two drugs in sports in 2004. The authors report an authentic case involving adrafinil and modafinil. The laboratory was requested to test for adrafinil in a hair strand collected from a woman found in possession of vials of adrafinil and suspected of trafficking. A specific method was developed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Unlike modafinil (varying from 6.8 to 13.9 ng/mg), adrafinil was not identified in the strand. The interpretation of the results was difficult because this is the first case describing human hair analysis. In order to be able to interpret the results, a self-administration study was conducted after an oral administration to a volunteer (200 mg) whose beard hair was collected 10 days after administration. The analysis of this specimen highlighted the presence of adrafinil at 0.8 ng/mg and modafinil at 0.5 ng/mg. These results demonstrate the dual identification of both compounds after a single consumption, even after administration of a low dose. According to these results, the analysis of the hair strand from the authentic case does not match with a consumption of adrafinil, in accordance with abuse of modafinil alone. Intelligence considered that this was a trafficking case of adrafinil, with no self-consumption.  相似文献   
32.
The illegal use of formalin (commercial formaldehyde) in cosmetic products harms the health of individuals exposed to this substance. Over the last years, the commercial availability of these products, especially those containing irregular dosage of formaldehyde, has increased in Brazil. This work analyzes some products for hair treatment available in the Brazilian market and verifies their safety. The adopted analytical methodology involved sample derivatization with 2,4‐dinitrophenylhydrazine, followed by high‐performance liquid chromatography with ultraviolet detection (UV–VIS) at λ = 365 nm. The limit of quantification is 2.5 × 10?3% w/w, and the recovery tests were around 93%. Some of the samples contained high and illegal formaldehyde levels ranging from 9% to 19% (w/w) and others presented suitable concentrations of the analyte. On the basis of the results, this work discusses the efficiency and practicality of this analytical method for forensic purposes.  相似文献   
33.
A fatal case of 1,4-butanediol (1,4-BD) oral ingestion is reported here, in which a 51-year-old man was found dead in his bed. According to the police report, the deceased was a known drug user. A glass bottle labeled (and later confirmed to be) “Butandiol 1,4” (1,4-BD) was found in the kitchen. Furthermore, the deceased's friend stated that he consumed 1,4-BD on a regular basis. The autopsy and histological examination of postmortem parenchymatous organ specimens did not revealed a clear cause of death. Chemical-toxicological investigations revealed gammahydroxybutyrat (GHB) in body fluids and tissues in the following quantities: femoral blood 390 mg/L, heart blood 420 mg/L, cerebrospinal fluid 420 mg/L, vitreous humor 640 mg/L, urine 1600 mg/L, and head hair 26.7 ng/mg. In addition, 1,4-BD was qualitatively detected in the head hair, urine, stomach contents, and the bottle. No other substances, including alcohol, were detected at pharmacologically relevant concentrations. 1,4-BD is known as precursor substance that is converted in vivo into GHB. In the synoptic assessment of toxicological findings, the police investigations and having excluded other causes of death, a lethal GHB-intoxication following ingestion of 1,4-BD, can be assumed in this case. Fatal intoxications with 1,4-BD have seldom been reported due to a very rapid conversion to GHB and, among other things, non-specific symptoms after ingestion. This case report aims to give an overview to the published of fatal 1,4-BD-intoxications and to discuss the problems associated with detection of 1,4-BD in (postmortem) specimens.  相似文献   
34.
The results are reported of a study to examine case factors associated with 732 wrongful convictions classified by the National Registry of Exonerations as being associated with “False or Misleading Forensic Evidence.” A forensic error typology has been developed to provide a structure for the categorization and coding of factors relating to misstatements in forensic science reports; errors of individualization or classification; testimony errors; issues relating to trials and officers of the court; and evidence handling and reporting issues. This study, which included the analysis of 1391 forensic examinations, demonstrates that most errors related to forensic evidence are not identification or classification errors by forensic scientists. When such errors are made, they are frequently associated with incompetent or fraudulent examiners, disciplines with an inadequate scientific foundation, or organizational deficiencies in training, management, governance, or resources. More often, forensic reports or testimony miscommunicate results, do not conform to established standards, or fail to provide appropriate limiting information. Just as importantly, actors within the broader criminal justice system—but not under the purview of any forensic science organization—may contribute to errors that may be related to the forensic evidence. System issues include reliance on presumptive tests without confirmation by a forensic laboratory, use of independent experts outside the administrative control of public laboratories, inadequate defense, and suppression or misrepresentation of forensic evidence by investigators or prosecutors. In approximately half of wrongful convictions analyzed, improved technology, testimony standards, or practice standards may have prevented a wrongful conviction at the time of trial.  相似文献   
35.
Forensic casework samples often include human hairs, teeth, and bones. Hairs with roots are routinely processed for DNA analysis, while rootless hairs are either not tested or processed using mitochondrial DNA. Bones and teeth are submitted for human remains identifications for missing persons and mass disaster cases. DNA extraction from these low templates and degraded samples is challenging. The new InnoXtract DNA extraction method utilizes magnetic beads that are optimized to bind small DNA fragments, as small as 100 base pairs, to purify high-yield DNA from compromised samples. This validation study evaluates InnoXtract's ability to obtain amplifiable DNA from samples such as rootless hairs and skeletal remains. Studies performed include sensitivity, stability, repeatability, reproducibility, non-probative samples, and comparison to standard organic extractions. Sensitivity studies demonstrate average yield recoveries ranging from 53% to 100% and 73% to 85% for the InnoXtract hair and bone methods, respectively. Studies demonstrate consistent results across a range of sample types, such as insulted and un-insulted bone and teeth, as well as hair shafts from donors of various ages, gender, race, and hair characteristics. The InnoXtract bone method outperformed organic extraction. The method was successfully automated on a MagMAX™ Express-96, with recoveries over 70% relative to the manual version. InnoXtract has the potential as an automated high-throughput, high-yield bone extraction method with 6 h of total extraction time for up to 96 samples. The validation study results demonstrate that the InnoXtract kits produce high-yield and high-quality DNA from compromised bone, teeth, and hair shaft samples.  相似文献   
36.
HS-SPME-GC/MS法检测尿液及毛发中苯丙胺类毒品   总被引:1,自引:1,他引:0  
目的采用顶空固相微萃取(HS-SPME)、GC/MS分析方法,对生物样品中苯丙胺(AM)、甲基苯丙胺(MAM)、3,4-亚甲二氧基苯丙胺(MDA)和3,4-亚甲二氧基甲基苯丙胺(MDMA)4种苯丙胺类毒品进行定性定量分析。方法在碱性和饱和盐处理状态下,采用100μm聚二甲基硅氧烷(PDMS)萃取纤维,于顶空瓶中进行生物样品AM、MAM、MDA、MDMA 4种毒品萃取,以2-甲基苯乙胺为内标,经气-质联用选择离子检测(GC/MS/SIM)模式进行定性定量分析。对HS-SPME条件优化,对方法的精密度、准确度和检出限进行测定。结果 AM、MAM、MDA、MDMA 4种毒品尿液中的最低检出限为5ng/mL,毛发中的最低检出限为0.5ng/mg。尿液中线性关系范围为0.05μg/mL~5μg/mL,r〉0.991,回收率为82%~108%,RSD为2.6%~6.1%(n=5);毛发中线性关系范围为5ng/mg~500ng/mg,r〉0.992,回收率为80%~113%,RSD(%)为1.4%~6.8%(n=5)。结论 HS-SPME-GC/MS各项定量参数符合分析要求。该方法简单、灵活、经济、快速、无溶剂,适用于生物检材中该类毒品的分析。  相似文献   
37.
38.
A rapid colorimetric method for detection of p‐phenylenediamine (PPD) in various biological samples is developed. The o‐cresol test for acetaminophen detection has been modified to detect PPD in blood, urine, gastric contents, and liver. After precipitating protein with trichloroacetic acid solution (2 mL, 10% w/v), biological specimens were required to convert PPD metabolites to PPD by acid hydrolysis. Finally, o‐cresol solution (1 mL, 1% w/v), hydrogen peroxide (200 μL, 3%v/v), and concentrated ammonium hydroxide (0.5 mL) were added in the biological samples. The presence of PPD was indicated by formation of violet color which was turned to bluish green color within 10–15 min. The limit of detection was found to be 2 mg/L in blood, urine, and gastric contents and 2 mg/Kg in liver. This method is also free from any potential interference by p‐aminophenol, acetaminophen, and other amine drugs under test conditions. This method was successfully employed to thirteen fatal cases of PPD poisoning.  相似文献   
39.
目的通过分段分析头发中的氯硝西泮,对药物辅助犯罪案件中受害人的摄药频度及摄药史进行推断。方法采用液氮冷冻研磨技术联合超声浴技术,以液相色谱-串联质谱法,对6名不同案件中受害人的头发分段分析,并测定各头发段中的氯硝西泮及7-氨基氯硝西泮的含量。结果 6名受害人的部分头发段中均检出氯硝西泮及其代谢物7-氨基氯硝西泮,且头发中药物峰值浓度的出现时间与受害人自述摄药时间相一致。结论头发分段分析可提供摄药频度与摄药时间信息,在药物辅助犯罪案件中具有独特的证据价值。  相似文献   
40.
Since July 2004, Mitotyping Technologies has been amplifying and sequencing a approximately 150 base pair fragment of mitochondrial DNA (mtDNA) that codes for 12S ribosomal RNA, to identify the species origin of nonhuman casework samples. The approximately 100 base pair sequence product is searched at http://www.ncbi.nlm.nih.gov/BLAST and the species match is reported. The use of this assay has halved the number of samples for which no mtDNA results are obtained and is especially useful on hairs and degraded samples. The availability of species determination may aid forensic investigators in opening or closing off lines of inquiry where a highly probative but challenging sample has been collected.  相似文献   
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