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51.
Novel synthetic opioids contribute considerably to the opioid epidemic, especially with the frequent emergence of structurally similar compounds. This case report describes a fatal intoxication involving 2-methyl AP-237. A 54-year-old Caucasian male was found deceased from an apparent drug overdose. A plastic container labeled “2MAP” and a cut straw were found in the decedent's backpack at the scene. A white substance found in the container tested positive for fentanyl by field testing. According to his medical history, the decedent was treated for a drug overdose 3 years prior to his death. With no diagnostic findings at autopsy, the case was submitted for toxicological analysis. An unknown substance was detected in peripheral blood and urine using gas chromatography with nitrogen phosphorous detection (GC-NPD). Further testing was conducted using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) which confirmed the presence of 2-methyl AP-237 and potential metabolites in blood and urine. Quantitation by GC-NPD revealed concentrations of 2-methyl AP-237 in blood and urine at 480 ng/mL and 4200 ng/mL, respectively. The toxicological analysis also identified and quantitated alprazolam in the blood at 55 ng/mL. Additionally, the metabolism of 2-methyl AP-237 was investigated and three hydroxylated metabolites were identified in peripheral blood and urine. Limited literature is available for the detection and quantitation of 2-methyl AP-237 in postmortem specimens. Given the toxicological findings with unremarkable autopsy findings, this case is an example of a fatal intoxication involving 2-methyl AP-237.  相似文献   
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The secondary dentin deposition that occurs after the tooth formation process results in a decrease in pulp cavity volume in adolescents and adults. The purpose of this critical review was to correlate pulpal and/or dental volume on cone-beam computed tomography (CBCT) with chronological age approximation. A subobjective was to investigate which methodology and CBCT technical parameters would be most appropriate to evaluate this correlation. This critical review followed the PRISMA guidelines, and it was conducted by a search through PubMed, Embase, SciELO, Scopus, Web of Science, Cochrane Library databases, as well as gray literature. Primary studies that used pulp volume, or pulp chamber to tooth volume ratio measured using CBCT were included. Seven hundred and eight indexed and 31 non-indexed records were identified. A qualitative analysis was performed including 25 selected studies with a total of 5100 individuals, age ranging from 8 to 87 years without sex predilection. The most used method was pulp volume/tooth volume. CBCT voxel size ranged between 0.09 and 0.5. Manual segmentation associated with threshold algorithms was used in most of the studies. Correlation between the pulp volume/tooth volume ratio was moderate: −0.66 for the upper central incisors, −0.59 for upper canines and −0.56 for lower canines. High heterogeneity was observed among the studies. It is concluded that pulp volume should be used with caution in age estimation. Evidence supports the preferable use of upper incisors with pulp volume/tooth volume ratio for age estimation. There is not enough evidence that voxel size interferes in age estimation by pulp volume.  相似文献   
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Angle grinders are one of the most dangerous and frequently used tools in industrial settings. Angle grinder injuries range from superficial cuts to deep penetrating injuries with underlying fracture-dislocation and vascular trauma. The injuries caused by angle grinders mostly involve the head, face, or upper limbs, while the lower limb is an unusual site. The high-speed rotating disc of the angle grinders does not respect anatomical boundaries or structures; therefore, the injuries caused may be disfiguring, permanently incapacitating, or even fatal. We report a fatal case of an angle grinder injury to the lower limb. The victim sustained a sharp cut over the left thigh while woodworking in an industrial setup. The rotating disc of an angle grinder had transected the skin, subcutaneous fat and muscles, and both the femoral vessels of the left side, which led to fatal exsanguination within 10 min of the incident.  相似文献   
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DNA extraction from and DNA typing of fresh water-exposed aged bone specimens poses a challenging task and is not very well examined. This study presents a new method to extract typable DNA from such problematic bone specimens. The procedure comprises low-heat drilling and cryogrinding, mild lysis conditions, and silica-column-based DNA cleaning. DNA quantity is assessed by quantitative PCR prior to short tandem repeat (STR) amplification. The procedure was employed with a 67-year-old tibia bone fragment recovered from a fresh water lake and succeeded to produce a full STR profile using the MPX-SP1 and MPX-SP2 mini-STR kits and a partial profile with 12 successfully amplified STRs using the Identifiler STR kit. The new method for the extraction of DNA from aged fresh water-exposed bone specimens presented herein was successfully applied to prepare DNA of sufficient quality and quantity to generate a full STR profile.  相似文献   
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In 2009 cutoff values of assessment criteria to testify abstinence control in order to estimate driving ability were standardized in Germany. The cutoff values are lower than required in existing guidelines like SAMHSA and there is critical discussion about detection of low concentrations by using immunoassay, especially concerning amphetamines in urine (50 ng/ml). In this study Direct ELISA kits were tested for their applicability to identify the absence of amphetamines, cannabinoids, opiates, cocaine, methadone and benzodiazepines in urine. Results were confirmed by LC/MS or GC/MS analyses. Sensitivity, specificity, predictive values (positive as well as negative) and overall misclassification rates were evaluated by contingency tables and were compared to ROC-analyses. Sensitivity results as well as specificity results were satisfying showing sensitivity values higher than 96% for each analyte. The amphetamine test we used showed sensitivity and specificity of 100% and 88%, respectively, even if amphetamine tests usually react with high cross-reactivity. Our study results include high discrimination at required cutoff values between positives and negatives for each drug group and demonstrate that immunological tests complying with requirements of current decreased urine cutoff values for assessment of driving ability do exist.  相似文献   
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Postmortem biochemical examination of synovial fluid--a preliminary study   总被引:2,自引:0,他引:2  
Vitreous humor chemistry is used for postmortem analysis since serum values of many components are thought to be reflected in vitreous humor and to be stable for a prolonged postmortem interval (pmi). A similar isolated compartment to vitreous humor is synovial fluid which up to now was hardly used for postmortem chemistry.The aim of the present examination was to compare the values of various analytes in both fluid compartments to get first hints for the reliability of the examination of synovial fluid. Therefore, in 74 cases of sudden death both fluids were taken and analysed for natrium, potassium, calcium, chloride, urea, creatinine, and glucose. The results show that the examination of synovial fluid as compared to vitreous humor is a reliable method to get hints on the premortal metabolic status since most analytes are stable postmortem. The range of all values is comparable in both fluids. The time course of glucose concentrations and, much more important, potassium concentrations is nearly similar. If no vitreous humor is available synovial fluid may be used with all precautions in diagnosis known from vitreous humor.  相似文献   
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