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1.
Artículo en Inglés | MEDLINE | ID: mdl-38512708

RESUMEN

Introduction: Δ9-tetrahydrocannabinolic acid A (THCA-A) is one of the main ingredients of cannabis plants and is converted to the psychoactive substance Δ9-tetrahydrocannabinol (THC) by decarboxylation during heating above ∼90°C. During the consumption of cannabis, a varying proportion of THCA-A is absorbed into the body. Therefore, the quantification of THCA-A in serum/plasma might provide additional information on consumption behavior in driving under the influence of cannabis cases. Materials and Methods: In this study, an already established gas-chromatography mass-spectrometry (GC-MS) method for the quantification of THC, 11-OH-THC, and THC-COOH in serum and plasma samples was extended to include THCA-A. This validated method was then applied to 1228 routinely achieved serum/plasma samples from drivers suspected of cannabis consumption in Western Saxony. Two different grouping systems for chronic/occasional consumption, one system for acute/subacute consumption, Huestis formulas, and the cannabis influence factor (CIF) were used for evaluation. Results: Method validation showed appropriate results for forensic toxicological routine analysis. Limit of detection and lower limit of quantification (LLOQ) for THCA-A were 0.3 and 1.0 ng/mL, respectively. Reproducibility was <11% and accuracy ranged between 104% and 107%. THCA-A was stable in native samples at least for 2 weeks at room temperature or 4°C as well as 1 month at -20°C. Freeze-thaw stability for three cycles and processed sample stability over 3 days was proven. A total of 865 cases with a THC concentration above the German analytical cutoff of 1 ng/mL as well as the analytical LLOQs of 0.9 and 2.5 ng/mL for 11-OH-THC and THC-COOH, respectively, were included in further statistical analysis. In 407 (47.1%) of these samples, THCA-A was quantifiable. Different statistical analyses indicated a correlation between THCA-A and THC concentrations in cases of chronic and acute consumption. In addition, an increase of chronic and acute cases with increasing THCA-A concentrations was observed. However, no correlation between THCA-A and CIF was found. Discussion: These data show that THCA-A might be an additional indicative marker to provide information about consumption frequency and acuteness. Additional studies with known consumption frequencies and times are required to verify these findings.

2.
Drug Test Anal ; 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37652872

RESUMEN

The semisynthetic cannabinoid hexahydrocannabinol (HHC) is currently getting a lot of media attention because the legal status in many countries is not clearly specified. In this study, a GC-MS method for the quantification of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC), and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) was extended to (9R)- and (9S)-HHC. The applicability was proven by serum/plasma samples from drivers suspected of cannabis consumption. Limit of detection (LOD) and lower limit of quantification (LLOQ) were 0.15 and 0.25 ng/mL, respectively. Within-run imprecision was <6.5% and between-run imprecision was <10.0%. Inter-injection stability, processed sample stability (3 days), freeze-thaw stability (three cycles), and storage stability (1 week room temperature; 1 month 4°C, -20°C) could be proven. Both HHC diastereomers could be detected in 17 (5.3%) out of 321 analyzed samples from traffic controls in Western Saxony. The mean ratio between (9R)- and (9S)-HHC was 1.99 (CV = 14.6%). Quantification resulted in concentrations between

3.
J Blood Med ; 14: 435-443, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37576590

RESUMEN

Introduction: Reporting of transfusion reactions is good practice and required by many guidelines. Errors in the transfusion chain can also lead to severe patient reactions and depend on active error reporting. We aimed to characterize transfusion incidents and asked whether workup of transfusion reactions may also contribute to revealing logistical errors. Methods: Transfusion medical records from 2011 to 2019 at our tertiary medical centre, as well as forensic autopsy reports, digitized sections, and court records from 1990 to 2019 were analysed. A total of 230,845 components were transfused between 2011 and 2019 at our own institution. Results: Overall, 322 transfusion incidents were reported. Of these, 279 were from our own institution, corresponding to a frequency of 0.12% of all transfusions. The distribution of reaction types is consistent with the literature, with allergic reactions (55.9%), febrile-non-hemolytic reactions (FNHTR, 24.2%), hemolytic reactions (3.4%) and other types at smaller frequencies (<3%). Twenty-nine (10.4%) of the 279 reports revealed logistical errors, including hemoglobin above guideline threshold (4.3%), incorrect or non-performed bedside tests (3.2%), inadequate patient identification (2.5%), laboratory and issuing errors, missed product checks or failure to follow recommendations (1.1% each). Eight of 29 (27.5%) of the logistical errors were detected by serendipity during workup of incident reports. In addition, 8/932 autopsy cases under code A14 (medical treatment errors) were found to be transfusion-associated (0.9%). Conclusion: Systematic workup of transfusion incidents can identify previously undetected errors in the transfusion chain. Passive reporting of errors through the recording of side effects may serve as a tool to assess more closely assess the frequency and quality of handling errors in real life, and thus serve to improve patient safety.

4.
Talanta ; 253: 123965, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36208557

RESUMEN

The sensitive and simultaneous measurement of multiple neurotransmitters in microdialysate (MD) of freely moving mice is a prerequisite to study neurochemical imbalances in specific brain regions. The quantitative analysis of 16 neurotransmitters and metabolites, including serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), melatonin (ME), dopamine (DA), levodopa (l-DOPA), 3-methoxytyramine (3-MT), norepinephrine (NE), epinephrine (EP), homovanillinic acid (HVA), acetylcholine (ACh), deoxy carnitine (iso-ACh), choline (Ch), and É£-aminobutyric acid (GABA), adenosine (ADE), glutamine (Gln), and glutamic acid (Glu) was achieved within a chromatographic separation time of 6.5 min by the application of a biphenyl column coupled to an API-QTrap 5500 (AB SCIEX) mass spectrometer. Optimized chromatographic separation as well as high sensitivity allow the simultaneous analysis and precise quantification of 16 neurotransmitters and metabolites in artificial cerebrospinal fluid (CSF). Sample preparation procedure consisted of simply adding isotopically labeled internal standard solution to the microdialysis sample. The limits of detection in aCSF ranged from 0.025 pg (Ch) to 9.75 pg (Gln) and 85.5 pg (HVA) on column. Recoveries were between 83 and 111% for neurotransmitter concentrations from 0.6 to 45 ng/ml or 200 ng/ml with a mean intra-day and inter-day coefficient of variation of 7.6% and 11.2%, respectively. Basal extracellular concentrations of the following analytes: 5-HT, 5-HIAA, ME, DA, 3-MT, HVA, ACh, iso-ACh, Ch, GABA, ADE, Gln, and Glu were determined in the striatum of mice with a MD flow rate of 0.5 µl/min. This LC-MS/MS method leads to an accurate quantification of ACh and its isobaric structure iso-ACh, which were detected in the MD samples at ratios of 1:8.6. The main advantage of the high sensitivity is the miniaturization of the MD protocol with short sample collection times and volumes down to 5 µl, which makes this method suitable for pharmacological intervention and optogenetic studies to detect neurochemical changes in vivo.


Asunto(s)
Serotonina , Espectrometría de Masas en Tándem , Animales , Ratones , Cromatografía Liquida , Neurotransmisores , Ácido gamma-Aminobutírico
5.
Sci Justice ; 62(5): 520-529, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36336445

RESUMEN

Human-driven biodiversity loss is progressively becoming a problem with dramatic consequences for the conservation of vital ecosystems. The increasing number of illegal killings of the grey wolf (Canis lupus, Linnaeus, 1758), a threatened species, displays the need for investigation and prosecution of such offences. Forensic entomology makes use of the knowledge about necrophagous insects to estimate a minimum time-since-death interval of the deceased person or animal, which can give important information on a possible perpetrator. The cadaver fauna along five decomposition stages of wolves in Germany was investigated in the period 2014-2021. The insects from 70 wolf cadavers, originating from all over Germany, were provided by the Leibniz Institute for Zoo and Wildlife Research Berlin. The accumulated degree day (ADD) model was applied for the post-mortem interval estimation on wolf cadavers for the first time. A total of 20 coleopteran species and 14 different dipteran species were discovered and identified. Almost 99 % of all insect specimens were from the order of Diptera, and beetles (Coleoptera) accounted for only 1 % of the cadaver fauna. The blowflies (Calliphoridae) are of particular importance for forensic issues, accounting for about 66 % of all families. Carrion beetles (Silphidae) were found as the second most abundant family (about 21 %). In addition, combining all cases, a steadily increasing insect species richness S was detected from early decay to advanced decay (fresh S = 8; bloated S = 12; active decay S = 21; advanced decay S = 34). In the following remains stage, the species number decreased again (S = 24). However, no significant difference in the number of species was found between the stages of decay when the cases were considered individually. The temporal pattern of insect appearance was found to be congruent with those of previous studies. Furthermore, a time of death was determined for each case and compared to the pathologist's estimates. This study provides insights into the arthropod fauna of wolf remains for the first time, applies the ADD-Model for post-mortem interval estimation, and discusses the suitability of forensic entomology for wildlife death investigations.


Asunto(s)
Escarabajos , Dípteros , Lobos , Animales , Humanos , Cambios Post Mortem , Ecosistema , Entomología , Cadáver , Insectos , Conducta Alimentaria
8.
Int J Legal Med ; 134(6): 2187-2193, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32372233

RESUMEN

Traumatic brain injury is among the leading causes of death in individuals under 45 years of age. However, since trauma mechanisms and survival times differ enormously, the exact mechanisms leading to the primary and secondary injury and eventually to death after traumatic brain injury (TBI) remain unclear. Several studies showed the versatile functions of microglia, the innate macrophages of the brain, following a TBI. Earlier being characterized as rather neurotoxic, neuroprotective capacities were recently demonstrated, therefore, making microglia one of the key players following TBI. Especially in cases with only short survival times, immediate microglial reactions are of great forensic interest in questions of wound age estimation. Using standardized immunohistochemical methods, we examined 8 cases which died causatively of TBI with survival times between minutes and 7 days and 5 control cases with cardiovascular failure as the cause of death to determine acute changes in microglial morphology and antigen expression after TBI. In this pilot study, we detected highly localized changes in microglial morphology already early after traumatic damage, e.g., activated microglia and phagocyted erythrocytes in the contusion areas in cases with minute survival. Furthermore, an altered antigen expression was observed with increasing trauma wound age, showing similar effects like earlier transcriptomic studies. There is minute data on the direct impact of shear forces on microglial morphology. We were able to show localization-depending effects on microglial morphology causing localized dystrophy and adjacent activation. While rodent studies are widespread, they fail to mimic the exact mechanisms in human TBI response. Therefore, more studies focusing on cadaveric samples need to follow to thoroughly define the mechanisms leading to cell destruction and eventually evaluate their forensic value.


Asunto(s)
Lesiones Traumáticas del Encéfalo/patología , Macrófagos/citología , Microglía/citología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Cambios Post Mortem
10.
Sci Rep ; 9(1): 11771, 2019 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-31417126

RESUMEN

Knowledge on trauma survival time prior to death following a lethal traumatic brain injury (TBI) may be essential for legal purposes. Immunohistochemistry studies might allow to narrow down this survival interval. The biomarkers interleukin-6 (IL-6) and glial fibrillary acidic protein (GFAP) are well known in the clinical setting for their usability in TBI prediction. Here, both proteins were chosen in forensics to determine whether neuronal or glial expression in various brain regions may be associated with the cause of death and the survival time prior to death following TBI. IL-6 positive neurons, glial cells and GFAP positive astrocytes all concordantly increase with longer trauma survival time, with statistically significant changes being evident from three days post-TBI (p < 0.05) in the pericontusional zone, irrespective of its definite cortical localization. IL-6 staining in neurons increases significantly in the cerebellum after trauma, whereas increasing GFAP positivity is also detected in the cortex contralateral to the focal lesion. These systematic chronological changes in biomarkers of pericontusional neurons and glial cells allow for an estimation of trauma survival time. Higher numbers of IL-6 and GFAP-stained cells above threshold values in the pericontusional zone substantiate the existence of fatal traumatic changes in the brain with reasonable certainty.


Asunto(s)
Astrocitos/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Interleucina-6/metabolismo , Neuronas/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Traumáticas del Encéfalo/etiología , Lesiones Traumáticas del Encéfalo/mortalidad , Lesiones Traumáticas del Encéfalo/patología , Muerte Celular , Femenino , Expresión Génica , Proteína Ácida Fibrilar de la Glía/genética , Humanos , Inmunohistoquímica , Interleucina-6/genética , Masculino , Persona de Mediana Edad , Curva ROC , Adulto Joven
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