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141.
Pregabalin is a Schedule V controlled substance which is defined as the (S) enantiomer of 3‐(aminomethyl)‐5‐methylhexanoic acid. It is used legitimately to treat neuropathy in patients with diabetes as well as for epilepsy and fibromyalgia. Pregabalin is an amino acid and an amphoteric compound, which makes it difficult to analyze using the conventional GC‐MS instrumentation found in most forensic drug analysis laboratories. Problems associated with the traditional GC‐MS analysis of pregabalin include selective solubility, ring closure to the corresponding lactam in the GC injection port and/or the MS transfer line and difficulty with chiral derivatization due to the presence of a carboxylic acid moiety. Here, we show that these challenges can be overcome by methylating (capping) the carboxylic acid portion of the pregabalin molecule and converting to the corresponding methyl ester. Once the methyl ester is synthesized, chiral derivatization at the amine can be achieved to identify the controlled (S) enantiomer of pregabalin via GC‐MS. 相似文献
142.
Amvrosios Orfanidis M.Sc. Helen Gika Ph.D. Eleni Zaggelidou Ph.D. Orthodoxia Mastrogianni Ph.D. Nikolaos Raikos Ph.D. 《Journal of forensic sciences》2019,64(2):643-646
In several medico‐legal cases, bone samples analysis may provide the only source of toxicological information. This case study reports the analysis of a human bone specimen, belonging to a 46‐year‐old man, found 3 months after his death due to cervical–thoracic injuries in a motorcycle accident. Bone specimen was the only available material for toxicological analysis, among few skull hair and rotten skin. Analysis was performed by a newly developed and validated ultra‐high‐pressure liquid chromatography–mass spectrometry/mass spectrometry (UHPLC‐MS/MS) method, following simple and efficient sample pretreatment. The results were in accordance with the man's medical record: Alprazolam and zolpidem were found at 2.2 and 5.4 ng/g of bone, respectively. Both these drugs were prescribed to the deceased. 相似文献
143.
Akina Nara Ph.D. Chiho Yamada M.D. Ph.D. Kanju Saka B.S. Takanori Kodama M.S. Masaki Yoshida D.D.S. Ph.D. Kaori Iwahara D.D.S. Ph.D. Tetsuya Takagi M.D. Ph.D. 《Journal of forensic sciences》2019,64(6):1936-1942
Fentanyl transdermal patches have been used to treat cancer‐ and noncancer‐related chronic pain. However, its inappropriate or illegal application may cause fatal poisoning. We herein present the case of a Japanese woman in her 40s who was found dead with seven 25‐μg/h fentanyl transdermal patches on her body. We established a detailed toxicological analysis procedure to quantify fentanyl, and its metabolite norfentanyl, and other drugs (acetaminophen, allylisopropylacetylurea, celecoxib, estazolam, promethazine, and sertraline) in human whole blood by ultra‐high‐performance liquid chromatography–tandem mass spectrometry. The measured fentanyl and norfentanyl concentrations in the femoral and cardiac blood were 0.051 and 0.072 μg/mL and 0.033 and 0.076 μg/mL, respectively. The decedent's fentanyl concentrations were consistent with previously reported postmortem blood levels for fatal cases of poisoning by fentanyl transdermal patches. Based on the decedent's case history, autopsy findings, and toxicological analyses, the cause of death was identified as intoxication with transdermal fentanyl. 相似文献
144.
Eileen Peter Stephanie Seidenbecher Bernhard Bogerts Henrik Dobrowolny 《The journal of forensic psychiatry & psychology》2019,30(3):381-400
Personality, psychopathology, and motives of 44 surviving offenders committing mass murder in Germany over 25 years (1984–2009) were analyzed using court files and psychiatric expertises. Initially, 123 mass murders in Germany were detected in the time period 1980–2010 (inclusive deceased offenders). Using a data entry form based on ViCLAS (Violent Crime Linkage Analysis System), we categorized the 44 surviving mass murderers into three prototypes using the ‘TwoStep Cluster’-method (separation of the offenders in different groups depending on their similarity of specific items): 1. Narcissistic or aggressive men suffering from addiction or affective disorder, committing mass murder out of rage/hate when being intoxicated by alcohol, 2. Psychotic offenders with schizophrenia and comorbid substance abuse. 3. Aggressive, narcissistic or anxious adolescents, half of them suffering from affective disorder or ADHD, committing mass murder out of rage/hate. Not included are such events where the offenders died and therefore no court files or psychiatric expertises were available. Classification and subtyping of the offenders’ personalities and psychopathological conditions might help to improve the chances for an early detection of persons at risk. 相似文献
145.
In many Western countries, citizen knowledge of terrorist events is intrinsically shaped by the style of broadcasted messages published by the media. Media discourses regarding terrorist acts raise questions about how such rhetoric elicits fear in people who typically experience such events through news reports. However, we do not fully understand the impact of the media on perceptions of terrorism as clearly as we understand the relationship between the media and fear of crime. This study examines how media sources accessed actively (e.g. through newspapers; Internet) or passively (e.g. through television; radio) influence knowledge and fear of terrorism. We find receiving information about terrorism from multiple media sources increases fear of terrorism, but media sources accessed passively are not as influential as media sources accessed more actively. These results highlight how media consumption from various sources may affect one’s fear of terrorism, and further illustrates how the role of perceived knowledge may exacerbate or mitigate fear. Implications for policy and practice are discussed. 相似文献
146.
Analyzing and Interpreting Lime Burials from the Spanish Civil War (1936–1939): A Case Study from La Carcavilla Cemetery 下载免费PDF全文
Eline M. J. Schotsmans Ph.D. Almudena García‐Rubio M.Sc. Howell G. M. Edwards Ph.D. Tasnim Munshi Ph.D. Andrew S. Wilson Ph.D. Luis Ríos Ph.D. 《Journal of forensic sciences》2017,62(2):498-510
Over 500 victims of the Spanish Civil War (1936–1939) were buried in the cemetery of La Carcavilla (Palencia, Spain). White material, observed in several burials, was analyzed with Raman spectroscopy and powder XRD, and confirmed to be lime. Archaeological findings at La Carcavilla's cemetery show that the application of lime was used in an organized way, mostly associated with coffinless interments of victims of Francoist repression. In burials with a lime cast, observations made it possible to draw conclusions regarding the presence of soft tissue at the moment of deposition, the sequence of events, and the presence of clothing and other evidence. This study illustrates the importance of analyzing a burial within the depositional environment and taphonomic context. 相似文献
147.
Identification of Eight Synthetic Cannabinoids,Including 5F‐AKB48 in Seized Herbal Products Using DART‐TOF‐MS and LC‐QTOF‐MS as Nontargeted Screening Methods 下载免费PDF全文
Katherine N. Moore M.S. Demetra Garvin Pharm.D. Brian F. Thomas Ph.D. Megan Grabenauer Ph.D. 《Journal of forensic sciences》2017,62(5):1151-1158
Synthetic cannabinoids are sprayed onto plant material and smoked for their marijuana‐like effects. Clandestine manufacturers modify synthetic cannabinoid structures by creating closely related analogs. Forensic laboratories are tasked with detection of these analog compounds, but targeted analytical methods are often thwarted by the structural modifications. Here, direct analysis in real time coupled to accurate mass time‐of‐flight mass spectrometry (DART‐TOF‐MS) in combination with liquid chromatography quadruple time‐of‐flight mass spectrometry (LC‐QTOF‐MS) are presented as a screening and nontargeted confirmation method, respectively. Methanol extracts of herbal material were run using both methods. Spectral data from four different herbal products were evaluated by comparing fragmentation pattern, accurate mass and retention time to available reference standards. JWH‐018, JWH‐019, AM2201, JWH‐122, 5F‐AKB48, AKB48‐N‐(4‐pentenyl) analog, UR144, and XLR11 were identified in the products. Results demonstrate that DART‐TOF‐MS affords a useful approach for rapid screening of herbal products for the presence and identification of synthetic cannabinoids. 相似文献
148.
Chengzhi Li Ph.D. Dong Ma Ph.D. Kaifei Deng B.Sc. Yijiu Chen M.Sc. Ping Huang Ph.D. Zhenyuan Wang Ph.D. 《Journal of forensic sciences》2017,62(5):1345-1350
Estimating the postmortem interval (PMI) is very important in the forensic sciences. Although many approaches have been used for estimating the PMI, accurate PMI calculations are still difficult. In this study, four Sprague Dawley (SD) rats were sacrificed by suffocation, and muscle samples were collected by dissection at various time intervals (0, 48, 96, and 144 h) after death. All samples were probed using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) to obtain molecular images and data for principal component analysis (PCA). The results showed that the peaks at m/z 1511, 1543, 1564, 1586 clearly decreased in intensity from 0 to 144 h postmortem and that the time groups were separated from each other on the PCA score plot. The prediction model showed high recognition capability (95.93%) and cross‐validation (83.72%). Our work suggests that MALDI‐TOF MS can be used to determine the PMI. 相似文献
149.
Using Cluster Analysis and ICP‐MS to Identify Groups of Ecstasy Tablets in Sao Paulo State,Brazil 下载免费PDF全文
Camila Maione M.Sc. Vanessa Cristina de Oliveira Souza M.Sc. Loraine Rezende Togni M.Sc. José Luiz da Costa Ph.D. Andres Dobal Campiglia Ph.D. Fernando Barbosa Ph.D. Jr. Rommel Melgaço Barbosa Ph.D. 《Journal of forensic sciences》2017,62(6):1479-1486
The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples. 相似文献
150.
Ken‐ichiro Nakao Ph.D. Yuki Tatara M.S. Kazuhiko Kibayashi M.D. 《Journal of forensic sciences》2017,62(6):1554-1558
Bone samples are used for analysis of drugs in decomposed or skeletonized bodies. Toxicological analyses of buried bones are important for determining the causes and circumstances of death. In this study, methamphetamine and amphetamine concentrations in heart blood, thigh muscles, and thighbones were analyzed using solid‐phase extraction with liquid chromatography–tandem mass spectrometry. Methamphetamine concentrations in heart blood, thigh muscle, and thighbone ranged from 0.041 to 0.873 μg/mL, 0.649 to 2.623 μg/g, and 56.543 to 643.371 μg/g, respectively. Thighbone concentrations were significantly higher than those in heart blood or thigh muscles were. Methamphetamine concentrations in buried thighbone (4.010–45.785 μg/g) were significantly lower than those of unburied thighbones were (56.543–643.371 μg/g). Methamphetamine and amphetamine were detected in thighbones buried for 7–180 days. These findings indicate that the methamphetamine concentrations in bone are higher and decrease after burial in soil. 相似文献