1,721,041 research outputs found
From drug identification to systems toxicology
No full textBiomedical sciences are at the edge of an extraordinary transformation in the conduct of toxicological evaluations using modern biomolecular analysis techniques to elucidate mechanisms of toxicity. To this transformation have contributed the increasing power and availability of molecular measurement tools, the possibility of probing biological networks inside organisms, organs, tissues, and cells, the affordability of high-throughput characterization tools, and the availability of potent bioinformatic tools. The classical toxicant-by-toxicant approach, that has been applied to solve clinical and forensic toxicology challenges for decades, has now turned to a multidisciplinary approach. The application of the newest biomolecular measurements to the field of toxicology led to the emergence of new sub-disciplines, such as toxicogenetics, toxicoproteomics, and systems toxicology. The leading approaches are briefly reviewed, with a special focus on technological advances, the omics era, systems toxicology and the toxome
Guidelines for Testing Drugs under International Control in Hair, Sweat and Oral Fluid
No full textThe present Manual is a revision of the United Nations Office on Drugs and Crime (UNODC) manual Guidelines for Testing Drugs Under International Control (ST/NAR/30/Rev.2). This version has been prepared taking into account recent developments in analytical technology to detect conventional and new, unconventional drugs and is based on up-to-date scientific knowledge of the physiology and pharmacology
of the so-called “alternate” biological specimens, which today may offer important information, complementary to the analysis of the traditional biological specimens (blood and urine)
Prevalence and concentrations of sedative-hypnotic drugs in blood of drivers involved in road traffic crashes in the Padova region of Italy – not so easy to interpret
No full textBackground & Objectives: This study reports the prevalence and concentrations of sedative-hypnotic drugs as exemplified by benzodiazepines (BZD) and zolpidem (Z-hypnotic) in blood samples from drivers involved in road traffic accidents (RTA) in the Padova region of Italy. Another aim of the study was to estimate the prevalence of these drugs with concentrations in blood above the therapeutic intervals and above specific per se limits. Methods: A total of 4066 blood samples collected from drivers involved in RTA were analysed for the presence of alcohol, drugs of abuse and medicinal drugs with sedative-hypnotic properties. Prevalence of drivers positive for BZDs and zolpidem were reported according to the reporting limit of our laboratory (1 ng/mL) in a sort of zero tolerance approach and compared with the prevalence according to analytical cut-offs used in the “European Union's research project on Driving Under the Influence of Drugs, Alcohol and Medicines” (DRUID). The impairment-based, per se limits adopted in Norway and in England and Wales and the values used to define “therapeutic ranges” in blood and in plasma/serum were also applied to the case study. Results: 175 blood samples were positive for sedative-hypnotics above 1 ng/mL, with the following prevalence: diazepam 44%, nordazepam 41.8%, lorazepam 32.6%, zolpidem 28%, oxazepam 25.6%, alprazolam 16%, delorazepam 11,6%, lormetazepam 11,6%, temazepam 11.6%, clonazepam 11.6%, triazolam 6.9%, N-desalkylflurazepam 4.6%, bromazepam 2.3%. When applying DRUID analytical cut-offs, the prevalence of BZDs and zolpidem sharply decreases. Applying the impairing cut-offs used in Norway, 56% of positive samples were above the limits equivalent to a BAC of 0.2 g/L, 39% above the limits corresponding to 0.5 g/L, and 23% above the cut-off corresponding to 1.2 g/L. Only 1% of the drivers had drug concentrations above the per se concentration limits adopted in England and Wales [26]. When comparing blood levels with therapeutic ranges in plasma, bromazepam, lormetazepam and delorazepam were often found above the highest limits. The adjustment of the concentrations with the plasma-to-blood ratios causes a significant increase of cases above the therapeutic ranges in plasma. Conclusions: Sedative-hypnotic drugs are medicinal substances frequently identified in drivers involved in RTA, commonly in concentrations associated with driving impairment. Besides the concentrations of drugs in blood, several factors have to be considered to conclude that a driver was impaired. The frequent association with alcohol, cocaine and other BZDs, confirms the abuse potential of these medications
Photodegradation of Drugs of Abuse in Hair
No full textHair analysis is a valuable tool in clinical and forensic toxicology to demonstrate drug exposure when cases of chronic intoxication, use, abuse, or single dose consumption need to be diagnosed in the context of facilitated crimes, withdrawal controls, doping controls, or workplace drug testing, with a large window from weeks to months/years for drug detection. However, scalp hair is exposed to sunlight and/or artificial light for many hours per day; hence, the action of light on hair could alter the content of drugs/illicit drugs and/or metabolites and the xenobiotics can gradually disappear from the hair shaft or be transformed into other compounds having a different structure from the parent molecule. Thus, light exposure should be considered as a potential confounder in studies investigating xenobiotics in hair giving rise to reduced drug concentrations or even false negative results. On the other hand, the formation of new photodegradation products could lead to the identification of new markers of abuse useful in forensic evaluations. Although the importance of the potentially detrimental effect of light on the exogenous molecules present in the hair shaft is being recognized, very few studies are actually present in the literature about the photodecomposition of illicit drugs in this valuable biological specimen
Curie-point pyrolysis/GC/MS in the art field. 2 - The characterization of proteineaceous binders
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