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161.
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation.  相似文献   
162.
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   
163.
Aminoindanes are a class of novel psychoactive substances (NPSs) that have become more prevalent over the past decade. GC–MS is often utilized for identifying seized drugs and is well regarded for its ability to separate mixtures. However, certain aminoindanes have similar mass spectral data and require specific gas chromatographic stationary phases for separation. Derivatization is an alternative method that can be applied to GC–MS to enhance chromatographic results, providing more selective analysis in seized-drug identification. This study investigates derivatization techniques to provide options for forensic science laboratories in accurately identifying aminoindanes. Three derivatization reagents, N-methyl-bis(trifluoroacetamide) (MBTFA), heptafluorobutyric anhydride (HFBA), and ethyl chloroformate (ECF) were evaluated for the analysis of eight aminoindanes by GC–MS using two common gas chromatographic stationary phases, Rxi®-5Sil MS and Rxi®-1Sil MS. All three derivatization methods successfully isolated eight aminoindanes, including the isomers 4,5-methylenedioxy-2-aminoindane (4,5-MDAI), and 5,6-methylenedioxy-2-aminoindane (5,6-MDAI) that could not be differentiated prior to derivatization. Reduced peak tailing and increased abundance were observed after derivatization for all the compounds, and mass spectra of the derivatives contained individualizing fragment ions that allowed for further characterization of the aminoindanes. This excluded 4,5-MDAI and 5,6-MDAI as they shared the same characteristic ions and were only distinguishable by their retention times. All three derivatization techniques used in this study allow for successful characterization of the aminoindanes and give forensic science laboratories flexibility in their analysis approach when they encounter these compounds.  相似文献   
164.
Caffeine is the most widely consumed psychoactive agent worldwide and has the potential for abuse, but studies monitoring caffeine abuse in China are scarce. This study aims to estimate the prevalence of caffeine abuse in northwest China and investigate the correlation between caffeine and other drugs in hair and nails using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Fingernail clippings were collected from 376 participants in northwest China to detect caffeine and 13 other illicit psychoactive drugs and their metabolites. Paired hair and nail samples were collected from 39 participants to investigate the correlation between caffeine and other drugs in hair and nails. The samples were decontaminated, pulverized, and extracted by a high-throughput nail sample preparation method and analyzed by UPLC-MS/MS. The results showed a risk of caffeine abuse in northwest China, with concentrations ranging from 0.43 to 10.6 ng/mg for healthy volunteers, 0.49–246 ng/mg for caffeine abusers, and 0.25–363 ng/mg for drug addicts in community rehabilitation centers. Caffeine was detected together with other illicit psychoactive drugs and their metabolites. Furthermore, positive detection correlations were found between hair and nail samples. This study provides a current perspective on caffeine abuse in northwest China and demonstrates the practical use of UPLC-MS/MS for the simultaneous detection of caffeine and 13 illicit psychoactive drugs and their metabolites in hair and nails. The results highlight the potential of nails as a supplementary matrix when hair samples are unavailable and emphasize the need for handling caffeine carefully given its potential for abuse.  相似文献   
165.
Vortioxetine is an antidepressant recently licensed in USA and EU for the treatment of major depressive disorder. Neither fatal case due to overdose nor data about postmortem concentrations on blood or other specimens have been reported. The aims of this study were the development and validation of a method for vortioxetine analysis by Liquid Chromatography Tandem Mass Spectrometry (LC–MS/MS) in postmortem samples and its application in an authentic case. The method was validated and applied on blood, vitreous humor, bile, brain, liver, kidney, and gastric content. After protein precipitation, the supernatant was directly injected into LC–MS/MS. Analysis was carried out by Multiple Reaction Monitoring (MRM) mode. The authentic case concerned a 38 years-old woman, affected by depression, who was found hanged at home. The method determined an acceptable sensitivity, selectivity, linearity, precision, and accuracy for all matrices. No interference was shown for all matrices. The matrices do not significantly reduce the peak intensity of vortioxetine. No carryover was shown. Toxicological analysis of the authentic case showed vortioxetine in blood (234 ng/ml), vitreous humor (10.5 ng/ml), brain (490 ng/g), lung (479 ng/g), liver (3751 ng/g), kidney (798 ng/g), bile (2267 ng/ml) and gastric content (253 ng/ml). Our case suggests that even at blood concentrations of vortioxetine equal to 234 ng/ml, the subject was able to stage and carry out the hanging. Vortioxetine concentrations found in the other cadaveric samples (biological fluids, organs, and gastric content) may be helpful to evaluate further similar comparable cases.  相似文献   
166.
Potent synthetic opioids including fentanyl and its analogs are frequently encountered in the field and require detection and identification by first responders to maintain the safety of drug abusers, first responders, health-care providers, and the public at large. Due to the low concentration at which these substances may be encountered and the complicating matrices within which they may be dispersed, the use of portable gas chromatography–mass spectrometry (GC–MS) for their identification in the field offers great potential value. This research established that portable GC–MS is a useful method for the detection and identification of a large number of synthetic opioids, especially fentanyl and its analogs. In this study, 250 synthetic opioids and related substances including 210 fentanyl analogs were analyzed using portable GC–MS. It was concluded that 225 of the 250 (90.0%) opioids analyzed were successfully detected onboard at the time of analysis and identified as either the substance (55.2%) or an analog (34.8%). These outcomes have equivalent benefit for the field analysis of illicit drugs due to both initiating the same subsequent actions by first responders.  相似文献   
167.
The shortage of foster/adoptive parents being licensed to care for children in the public welfare system prompted an evaluation of the Licensure and Home Study Process (LHSP). Ecological systems theory framed the barriers-to-resources interplay among kinship and non-relative caregivers who withdrew or completed the LHSP. This mixed-methods study examined differences in applicant characteristics and types of barriers experienced. Results indicated that applicants responsible for other children in the home paired with welfare system barriers served as a tipping point for withdrawal. Relatives encountered the most barriers and all grandparents withdrew from the LHSP prior to licensure.  相似文献   
168.
正Since its introduction of the one-child policy for most Chinese couples in the late 1970s,China has effectively reined in its rampant population growth.Benef iting from the policy,Chinese women have been liberated from the birth burden to a great degree and their education and employment situation has improved dramatically.To promote long-term,balanced development of the population,China is gradually adjusting its family planning policy.On December 23,2013,a bill to allow couples to have two children if either parent is an only child was approved at the sixth meeting of the Standing Committee of the 12th National People’s Congress.The move marks another major adjustment to China’s family planning policy since the country allowed couples to have two children if both parents are only children.  相似文献   
169.
British local authorities and their partners are increasingly developing new ways of working together with local communities. The nature of this co-working, however, is complex, multi-faceted and little understood. This article argues for greater clarity of thinking on the topic, by analysing this co-working as a form of political co-governance, and drawing attention in particular to issues of scale and democracy. Using evidence from a study of 43 local authority areas, 16 authorities are identified where co-governance is practised, following three main types of approach: service-influencing, service-delivering and parish council developing. It is concluded that strengthening political co-governance is essential for a healthy democracy.  相似文献   
170.
In this article, we compare how administrative and political elites in The Netherlands, the European Union, and the United States perceive and prioritize four key public values—responsiveness, expertise, lawfulness, and transparency. Our data from 94 in-depth interviews show that political elites and administrative elites differ most in their perception and prioritization of expertise and transparency and less in responsiveness and lawfulness. Interestingly, these politico-administrative value differences largely hold across the institutional settings we study. Theorizing on our results, we formulate eight propositions for future studies. Our study contributes to public values research by using qualitative methodology and including politicians.  相似文献   
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