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1.
Meat Sci ; 215: 109538, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38772311

RESUMO

Mitochondria function and integrity may impact postmortem metabolism and meat quality development. Adaptations in heat tolerant Brahman may persist to limit cellular stress postmortem. Our objective was to evaluate glycolysis, pH decline, and mitochondria function in longissimus lumborum (LL) from Angus and Brahman steers (N = 28) early postmortem (1 to 6 h) and after rigor (24 h). We evaluated metabolites of anaerobic glycolysis, ATP, pH, and temperature, and determined mitochondria oxygen consumption rate (OCR) in permeabilized fibers. The main effects of breed (b) and time (t) and the interaction were tested. Brahman LL contained greater ATP during the first 6 h postmortem; Brahman also tended to exhibit a slower pH decline (b × t, P = 0.07) and more rapid temperature decline (b × t, P < 0.001), but metabolites of anaerobic glycolysis were not different. Mitochondria in Brahman and Angus LL were well-coupled and respired at 1 h postmortem. However, outer membrane integrity became increasingly compromised postmortem (t, P < 0.001). Brahman tended to exhibit greater electron transport system capacity (b, P < 0.1) and had greater capacity for oxidative phosphorylation (complex I and II substrates) at 6 h compared with Angus (P < 0.001). In totality, greater ATP, slower pH decline, and enhanced mitochondria capacity indicate that Brahman possess mitochondrial properties or cellular adaptations that help protect the cell during energy stress postmortem. Slower pH and more rapid temperature decline in LL from Brahman may also help preserve mitochondria function postmortem.

2.
Forensic Sci Int ; 360: 112031, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38723476

RESUMO

PURPOSE: The image contrast of postmortem magnetic resonance imaging (MRI) may differ from that of antemortem MRI because of circulator arrest, changes in postmortem tissue, and low-body-temperature scanning conditions. In fact, we have found that the signal intensity of white matter (WM) on T1-weighted spin-echo (T1WSE) images of the postmortem brain was lower than that of gray matter (GM), which resulted in image contrast reversal between GM and WM relative to the living brain. However, the reason for this phenomenon is unclear. Therefore, the aim of this study is to clarify the reason why image contrast reversal occurs between GM and WM of the postmortem brain. MATERIALS AND METHODS: Twenty-three corpses were included in the study (mean age, 60.6 years; range: 19-60 years; mean rectal temperature at scan, 6.9℃; range: 4-11℃). On a 1.5 T MRI system, postmortem T1W-SE MRI of the brain was conducted in the 23 corpses prior to medico-legal autopsy. Next, T1 and T2 of the GM and WM at the level of the basal ganglia were determined in the same participants using inversion recovery and multiple SE sequences, respectively. The proton density (PD) was also calculated from the T1 and T2 images (in the same slice). RESULTS: T1W-SE image contrast between the GM and WM of all postmortem brains was inverted relative to the living brain. T1 (579 ms in GM and 307 ms in WM) and PD (64 in GM and 44 in WM) of the postmortem brain decreased compared with the living brain. While T1 of WM/GM remained below 1 even postmortem, the PD of WM/GM decreased. T2 (110 ms in GM and 98 ms in WM) of the postmortem brain did not differ from the living brain. CONCLUSION: The decrease in PD of WM/GM in the postmortem brain may be the major driver of contrast reversal between the GM and WM relative to the living brain.

3.
NMR Biomed ; : e5171, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757603

RESUMO

Magnetic resonance spectroscopy (MRS) thermometry offers a noninvasive, localized method for estimating temperature by leveraging the temperature-dependent chemical shift of water relative to a temperature-stable reference metabolite under suitable calibration. Consequentially, this technique has significant potential as a tool for postmortem MR examinations in forensic medicine and pathology. In these examinations, the deceased are examined at a wide range of body temperatures, and MRS thermometry may be used for the temperature adjustment of magnetic resonance imaging (MRI) protocols or for corrections in the analysis of MRI or MRS data. However, it is not yet clear to what extent postmortem changes may influence temperature estimation with MRS thermometry. In addition, N-acetylaspartate, which is commonly used as an in vivo reference metabolite, is known to decrease with increasing postmortem interval (PMI). This study shows that lactate, which is not only present in significant amounts postmortem but also has a temperature-stable chemical shift, can serve as a suitable reference metabolite for postmortem MRS thermometry. Using lactate, temperature estimation in postmortem brain tissue of severed sheep heads was accurate up to 60 h after death, with a mean absolute error of less than 0.5°C. For this purpose, published calibrations intended for in vivo measurements were used. Although postmortem decomposition resulted in severe metabolic changes, no consistent deviations were observed between measurements with an MR-compatible temperature probe and MRS thermometry with lactate as a reference metabolite. In addition, MRS thermometry was applied to 84 deceased who underwent a MR examination as part of the legal examination. MRS thermometry provided plausible results of brain temperature in comparison with rectal temperature. Even for deceased with a PMI well above 60 h, MRS thermometry still provided reliable readings. The results show a good suitability of MRS thermometry for postmortem examinations in forensic medicine.

4.
Naturwissenschaften ; 111(3): 30, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758365

RESUMO

Succession patterns of carrion insects on large mammal's carrion has been widely studied, notably to estimate the post-mortem interval in forensic investigations as accurately as possible. However, little attention has been paid to the carrion insects living inside these bones once a carcass is skeletonized. One very recent study documented flies emerging from pig carcasses, and only scarce authors reported the presence of other carrion insects taking advantage of the bone marrow. We, thus, aimed to (1) estimate the frequency of inner-bone space colonization by carrion insects, with particular attention to bone-skipper flies; (2) identify the insects living inside the carrion bones; and (3) determine whether or not carrion insects found within the bones can successfully exit the bones and complete their development. We extensively sampled 185 large mammals' bones collected from twelve vulture feeding stations and four isolated carcasses in southwest France and northern Spain. Sampled bones were opened, and the insects found inside were identified. For two bones, foramen, i.e., the holes providing a natural entrance and exit to the bone's inner cavity, was monitored with a camera to assess the insect's putative exit. We describe the entomofauna, i.e., the set of insect species, living within the bones, and illustrate insects' ability to exit the bones for their subsequent development and maturity. These results are discussed in the framework of carrion insect conservation and forensic entomology perspectives.


Assuntos
Osso e Ossos , Entomologia Forense , Insetos , Mamíferos , Animais , Osso e Ossos/anatomia & histologia , Insetos/fisiologia , França , Espanha , Comportamento Alimentar/fisiologia , Dípteros/fisiologia , Dípteros/anatomia & histologia
5.
Anat Sci Int ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758496

RESUMO

Variations in the arch of the aorta and aortic valves among fetal, cadaveric, and post-mortem specimens present a spectrum of anatomical configurations, posing challenges in establishing a standard norm. While some variations hold surgical significance, many bear little functional consequence but provide insights into embryological origins. The aortic arch exhibits diverse branching patterns, including common trunks and different orders, relevant for endovascular surgeries. Meanwhile, malformations in the aortic valve, affecting the aorta, may lead to ischemia and cerebral infarction, warranting understanding of coexisting arch and valve anomalies to predict complications like aortic dissection. Studies in the Indian population mirror global variations, underscoring the need to explore embryological, clinical, and surgical implications for safer vascular surgeries involving the aortic arch and valves. The study's objectives included examining branching patterns, diameters, and distances between arch branches and exploring aortic valve variations. Employing a cross-sectional design, the study was conducted across Anatomy, Forensic Medicine, and Obstetrics and Gynecology departments. A sample of 100, comprising cadavers, fetuses, and postmortem specimens, were gathered. Specimens ranged from 14 weeks of intrauterine life to 85 years, with intact thoracic cages as inclusion criteria. Methodology involved dissection, specimen fixation, and macroscopic examination for variations and morphological parameters. Results showed aortic diameter increase with age, with significant gender differences. A statistically significant association between arch variations and anomalous valves was observed, suggesting mutual predictability. Individuals with valve anomalies should undergo comprehensive cardiology evaluation to avert complications like aortic dissection during endovascular surgeries. While atheromatous plaques were prevalent in younger groups, their frequency rose with age, necessitating vigilant vascular monitoring. Careful handling during surgeries is paramount, given potential adverse outcomes resulting from variations. Overall, the study underscores the importance of comprehensive anatomical understanding in clinical contexts, guiding effective management strategies and ensuring patient safety in vascular surgeries.

6.
Diagnostics (Basel) ; 14(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732299

RESUMO

In light of falling global autopsy rates, one of the causes of which is the resulting body disfigurement, it has become crucial to search for new, minimally invasive post-mortem diagnostic tools. One of these methods is videoautopsy, a minimally invasive autopsy technique using endoscopic methods. In the years 2020-2023, 15 videoautopsies were conducted at the Department of Forensic Medicine of the Poznan University of Medical Sciences in order to determine the usefulness of the method in forensic approaches. Each post-mortem examination included laparoscopy and thoracoscopy, followed by a classic autopsy to assess the effectiveness of the method. In total, the endoscopic examination allowed for determining the cause of death in 53.3% of cases, and when the cause of death was located in the abdominal cavity or chest, the percentage increased to 80%. Traumatic lesions had good recognition efficiency. In addition, it was also possible to collect material for histopathological and toxicological tests. Retroperitoneal organs were difficult to assess. The main limitation of the method is the inability to assess the inside of the skull and the structures of the central nervous system. Videoautopsy may become an important tool in post-mortem diagnostics and in forensic cases, especially when the alternative is to not perform an autopsy. Further research is necessary to standardise the examination protocol, optimise the instrumentation, and assess the potential synergistic effect with other methods of minimally and non-invasive post-mortem examination.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38713332

RESUMO

Epicardial adipose tissue (EAT) deposition has been long associated with heart weight. However, recent research has failed to replicate this association. We aimed to determine the association of EAT volume with heart weight in post-mortem cases and identify potential confounding variables. EAT volume derived from post-mortem computed tomography (PMCT) and heart weight were measured in post-mortem cases (N = 87, age: 56 ± 16 years, 28% female). Cases with hypertrophied heart weights (N = 44) were determined from reference tables. Univariable associations were tested using Spearman correlation and simple linear regression. Independence was determined with stepwise regression. In the total cohort, EAT volume (median 66 ± 45 cm3) was positively associated with heart weight (median 435 ± 132 g) at the univariable level (r = 0.6, P < 0.0001) and after adjustment for age, female sex, and various body size metrics (R2 adjusted = 0.41-0.57). Median EAT volume was 1.9-fold greater in cases with hypertrophic hearts (P < 0.0001) but with considerably greater variability, especially in cases with extreme EAT volume or heart weight. As such, EAT volume was not associated with heart weight in hypertrophic cases, while a robust independent association was found in non-hypertrophic cases (R2 adjusted = 0.62-0.86). EAT mass estimated from EAT volume found that EAT comprised approximately 13% of overall heart mass in the total cases. This was significantly greater in cases with hypertrophy (median 15.5%; range, 3.6-36.6%) relative to non-hypertrophied cases (12.5%, 3.3-24.3%) (P = 0.04). EAT volume is independently and positively associated with heart weight in post-mortem cases. Excessive heart weight significantly confounded this association.

8.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38712198

RESUMO

The hippocampus contains many unique cell types, which serve the structure's specialized functions, including learning, memory and cognition. These cells have distinct spatial topography, morphology, physiology, and connectivity, highlighting the need for transcriptome-wide profiling strategies that retain cytoarchitectural organization. Here, we generated spatially-resolved transcriptomics (SRT) and single-nucleus RNA-sequencing (snRNA-seq) data from adjacent tissue sections of the anterior human hippocampus across ten adult neurotypical donors. We defined molecular profiles for hippocampal cell types and spatial domains. Using non-negative matrix factorization and transfer learning, we integrated these data to define gene expression patterns within the snRNA-seq data and infer the expression of these patterns in the SRT data. With this approach, we leveraged existing rodent datasets that feature information on circuit connectivity and neural activity induction to make predictions about axonal projection targets and likelihood of ensemble recruitment in spatially-defined cellular populations of the human hippocampus. Finally, we integrated genome-wide association studies with transcriptomic data to identify enrichment of genetic components for neurodevelopmental, neuropsychiatric, and neurodegenerative disorders across cell types, spatial domains, and gene expression patterns of the human hippocampus. To make this comprehensive molecular atlas accessible to the scientific community, both raw and processed data are freely available, including through interactive web applications.

9.
J Biophotonics ; : e202400017, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714530

RESUMO

We utilize Laser Speckle Contrast Imaging (LSCI) for visualizing cerebral blood flow in mice during and post-cardiac arrest. Analyzing LSCI images, we noted temporal blood flow variations across the brain surface for hours postmortem. Fast Fourier Transform (FFT) analysis depicted blood flow and microcirculation decay post-death. Continuous Wavelet Transform (CWT) identified potential cerebral hemodynamic synchronization patterns. Additionally, non-negative matrix factorization (NMF) with four components segmented LSCI images, revealing structural subcomponent alterations over time. This integrated approach of LSCI, FFT, CWT, and NMF offers a comprehensive tool for studying cerebral blood flow dynamics, metaphorically capturing the 'end of the tunnel' experience. Results showed primary postmortem hemodynamic activity in the olfactory bulbs, followed by blood microflow relocations between somatosensory and visual cortical regions via the superior sagittal sinus. This method opens new avenues for exploring these phenomena, potentially linking neuroscientific insights with mysteries surrounding consciousness and perception at life's end.

10.
Cereb Cortex ; 34(13): 121-128, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696601

RESUMO

Previous studies in autism spectrum disorder demonstrated an increased number of excitatory pyramidal cells and a decreased number of inhibitory parvalbumin+ chandelier interneurons in the prefrontal cortex of postmortem brains. How these changes in cellular composition affect the overall abundance of excitatory and inhibitory synapses in the cortex is not known. Herein, we quantified the number of excitatory and inhibitory synapses in the prefrontal cortex of 10 postmortem autism spectrum disorder brains and 10 control cases. To identify excitatory synapses, we used VGlut1 as a marker of the presynaptic component and postsynaptic density protein-95 as marker of the postsynaptic component. To identify inhibitory synapses, we used the vesicular gamma-aminobutyric acid transporter as a marker of the presynaptic component and gephyrin as a marker of the postsynaptic component. We used Puncta Analyzer to quantify the number of co-localized pre- and postsynaptic synaptic components in each area of interest. We found an increase in the number of excitatory synapses in upper cortical layers and a decrease in inhibitory synapses in all cortical layers in autism spectrum disorder brains compared with control cases. The alteration in the number of excitatory and inhibitory synapses could lead to neuronal dysfunction and disturbed network connectivity in the prefrontal cortex in autism spectrum disorder.


Assuntos
Proteínas de Membrana , Córtex Pré-Frontal , Sinapses , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Humanos , Masculino , Feminino , Sinapses/patologia , Sinapses/metabolismo , Adulto , Pessoa de Meia-Idade , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/patologia , Adulto Jovem , Adolescente , Criança , Transtorno Autístico/metabolismo , Transtorno Autístico/patologia , Inibição Neural/fisiologia , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo
11.
BMC Ophthalmol ; 24(1): 219, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783230

RESUMO

PURPOSE: Vitreous humor (VH) is used for postmortem biochemical studies because it is well protected in an uncontaminated state even after death. The goal of this research was to investigate electrolyte concentrations in the VH from human eyes with and without a history of vitrectomy surgery. METHODS: We analyzed the sodium (Na), potassium (K), chloride (Cl) and magnesium (Mg) concentrations from 34 VH samples from 34 patients. Eleven samples were from eyes with a history of vitrectomy, and the remaining 23 eyes had no history of vitrectomy. The correlations of Na, K, Cl and Mg concentrations with patient age, interval between first and second vitrectomy, and lens status (history of cataract surgery) were also evaluated. RESULTS: The Na, K, Cl and Mg concentrations in VH from vitrectomized eyes were 134.1 ± 7.9 mmol/L, 3.7 ± 0.2 mmol/L, 99.7 ± 6.7 mmol/L and 0.59 ± 0.09 mmol/L, respectively; all were significantly lower than the corresponding concentrations in VH from control eyes (lower by 5.0%, 11.0%, 11.7%, and 22.6%, respectively). Na, K, Cl and Mg concentrations in VH from vitrectomized eyes did not show significant correlations with patient ages or the interval between their first and second vitrectomies. There were no significant differences in Na, K, Cl and Mg concentrations in VH between phakic eyes and intraocular lens-implanted eyes. CONCLUSIONS: With the increasing number of vitrectomies being performed, it is necessary to consider the history of vitrectomy when using a subject's VH in forensic examination.


Assuntos
Vitrectomia , Corpo Vítreo , Humanos , Corpo Vítreo/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto , Eletrólitos/análise , Medicina Legal/métodos , Sódio/análise , Potássio/análise , Magnésio/análise
12.
Biomolecules ; 14(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38785943

RESUMO

In the present study, we conducted a scoping review to provide an overview of the existing literature on the carbocyanine dye DiI, in human neuroanatomical tract tracing. The PubMed, Scopus, and Web of Science databases were systematically searched. We identified 61 studies published during the last three decades. While studies incorporated specimens across human life from the embryonic stage onwards, the majority of studies focused on adult human tissue. Studies that utilized peripheral nervous system (PNS) tissue were a minority, with the majority of studies focusing on the central nervous system (CNS). The most common topic of interest in previous tract tracing investigations was the connectivity of the visual pathway. DiI crystals were more commonly applied. Nevertheless, several studies utilized DiI in a paste or dissolved form. The maximum tracing distance and tracing speed achieved was, respectively, 70 mm and 1 mm/h. We identified studies that focused on optimizing tracing efficacy by varying parameters such as fixation, incubation temperature, dye re-application, or the application of electric fields. Additional studies aimed at broadening the scope of DiI use by assessing the utility of archival tissue and compatibility of tissue clearing in DiI applications. A combination of DiI tracing and immunohistochemistry in double-labeling studies have been shown to provide the means for assessing connectivity of phenotypically defined human CNS and PNS neuronal populations.


Assuntos
Técnicas de Rastreamento Neuroanatômico , Humanos , Técnicas de Rastreamento Neuroanatômico/métodos , Carbocianinas/química , Sistema Nervoso Central , Sistema Nervoso Periférico , Corantes Fluorescentes/química
13.
Ultrasound Med Biol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38724329

RESUMO

OBJECTIVE: To compare the effectiveness of positive pressure (PP) and negative pressure (NP) for reducing gas inclusions in biological tissues in preparation for acoustic imaging. METHODS: Eighteen pieces of porcine liver in degassed saline were included in this study. For the PP group (n = 9 samples), a wristwatch waterproof tester was used to pressurize samples to 0.41 MPa (59 psi) for 10 min. For the NP group (n = 9 samples), a desiccator at -0.08 MPa (-12 psi) was used for 30 min. Backscatter coefficients (BSCs) were calculated over the central frequency range of the backscattered spectra and paired-samples t-tests were performed. RESULTS: Utilization of PP resulted in a decrease in BSC for all samples, indicating less gas post-PP (pre-PP -13.0 ± 4.3 dB [mean ± SD], post-PP -18.9 ± 5.0 dB, p = .001). Utilization of NP resulted in an increase in BSC for the majority of samples (pre-NP -14.6 ± 6.0 dB, post-NP -13.1 ± 5.3 dB, p = .177). CONCLUSION: Utilization of a simple PP chamber consistently resulted in a decrease in tissue gas, at lower pressures than previously reported. The vacuum method is ineffective, may result in a paradoxical increase in tissue gas, and may not be recommended for tissue degassing.

14.
J Forensic Sci ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38736208

RESUMO

Researchers have observed that rainfall may re-initiate decomposition in desiccated tissue; however, no conclusive research-based evidence exists on the specific effects of rehydration on decomposition. Therefore, this study aimed to assess the effects of artificial rehydration on the progression of decomposition following the advanced stage of decomposition. Twelve adult pig cadavers (8 experimental; 4 controls) were placed in the central Highveld of South Africa during cooler (April-July 2021) and warmer (August-November 2021) months. Decomposition was scored approximately biweekly to obtain the total body score, and accumulated degree days (ADD) were calculated for each pig. All pig cadavers were covered by chicken wire cages with transparent tarps to control for natural rehydration and scavenging. Once the experimental pig cadavers reached a three-visit stasis in the advanced phase of decomposition, they were artificially rehydrated, and changes in the progression of decomposition between the control and experimental groups were plotted (ADD against TBS) for observation. The rehydrated experimental pig cadavers showed re-initiation of decay and insect re-colonization, while the control cadavers mainly remained in a state of stasis with insect activity ceased altogether. Greater cadaver decomposition islands and a color change post-rehydration were also noted in some experimental cadavers. This supports the need for future research on the impact of rehydration, including associated soil moisture on decomposition rates, progression, and invertebrate colonization, which will enhance our understanding of the effects these environmental factors have on the accuracy of post-mortem interval estimation.

15.
Forensic Sci Int ; 359: 112001, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38714107

RESUMO

BACKGROUND: Cardiac implantable electronic devices (CIED) are a heterogeneous group of medical devices with increasingly sophisticated diagnostic capabilities, which could be exploited in forensic investigations. However, current guidelines are lacking clear recommendations on the topic. The first aim of this systematic review is to provide an updated assessment of the role of postmortem CIED interrogation, and to give practical recommendations, which can be used in daily practice. Secondly, the authors aim to determine the rates of postmortem CIED interrogation and autopsy investigations, the type of final rhythm detected close to death (with a focus on the significance of documented arrhythmias), as well as the role of postmortem CIED interrogation in the determination of final cause/time of death, and any potentially fatal device malfunctions. METHODS: A systematic search in MEDLINE and Scopus aiming to identify reports concerning postmortem human CIED interrogation was performed, including a systematic screening of reference lists. Case reports, letters to the editors, commentaries, review articles or guidelines were excluded, along with studies related to cardiac devices other than CIED. All data were pooled and analyzed using fixed-effects meta-analysis models, and the I2 statistic was used to assess heterogeneity. RESULTS: A total of 25 articles were included in the systematic review, enrolling 3194 decedent CIED carriers. Ten studies (40%) had a 100% autopsy rate, whereas in further 6 studies autopsy findings were variably reported; CIED interrogation was available from 22 studies (88%), and it was never performed prior to autopsy. The overall rate of successful postmortem CIED interrogation was 89%, with high heterogeneity among studies, mainly due to device deactivation/battery discharge. Twenty-four percent of CIED carriers experienced sudden cardiac death (SCD), whereas non-sudden cardiac and non-cardiac death (NSCD, NCD) were reported in 37% and 30% of decedents, respectively. Ventricular tachyarrhythmias were recorded in 34% of overall successfully interrogated CIED, and in 62% of decedents who experienced a SCD; of all ventricular tachyarrhythmias recorded, 40% was found in NSCD or NCD. A clear interpretation of the etiological role of recorded arrhythmias in the causation of death required integration with autopsy findings. Overall, potentially fatal device malfunctions were detected in 12% of cases. CONCLUSIONS: Postmortem CIED interrogation is a valuable tool for the determination of the cause of death, and may complement autopsy. Forensic pathologists need to know the potential utility, pitfalls, and limitations of this diagnostic examination to make this tool as much reliable as possible.


Assuntos
Desfibriladores Implantáveis , Marca-Passo Artificial , Humanos , Marca-Passo Artificial/efeitos adversos , Arritmias Cardíacas , Falha de Equipamento
16.
J Pharm Biomed Anal ; 245: 116176, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701535

RESUMO

Pesticides play an important role in forensic toxicology and are usually classified as a single class of chemicals. Despite their commonly perceived unity, pesticides encompass a spectrum of compounds, including organophosphates, carbamates, pyrethroids or organochlorines, among others, each with varying degrees of toxicity. Pesticide analysis in post-mortem samples can be difficult due to the complexity of the samples and to the high toxicity of these compounds. The aim of this study was to develop and validate an easy to use, sensitive, and robust method, using ultra-performance liquid chromatography-tandem mass spectrometry to be incorporated in the routine flow for pesticide analysis in post-mortem blood samples. Described herein is a streamlined, expeditious, yet highly efficient method facilitating the screening, qualitative assessment, and quantitative confirmation of 15 pesticides, including acetamiprid, azinphos-ethyl, bendiocarb, carbofuran, chlorfenvinphos, dimethoate, imidaclopride, malathion, methiocarb, methomyl, parathion, pirimicarb, strychnine, tetrachlorvinphos, and thiacloprid in post-mortem blood, recognizing the pivotal role blood plays in forensic investigations. The developed method was linear from 10 to 200 ng/mL; limits of detection were between 1 and 10 ng/mL, depending on the compound; it was successfully evaluated a dilution ratio of 1-2, 5 and 10; and 8 substances showed maximum stability for the time interval studied. This UHPLC-MS/MS method is useful and a powerful tool in a toxicology lab because it is fast, simple, effective, and trustworthy. The results of this validation highlight the robustness of the analytical method, providing a valuable tool for the accurate and sensitive detection of pesticides in post-mortem blood. Poised for routine implementation, this method has already found success in suspected intoxication cases, promising to elevate the standards of forensic pesticide analysis.


Assuntos
Autopsia , Toxicologia Forense , Praguicidas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Praguicidas/análise , Praguicidas/sangue , Toxicologia Forense/métodos , Reprodutibilidade dos Testes , Autopsia/métodos , Limite de Detecção
17.
Toxicol Rep ; 12: 542-545, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38778799

RESUMO

Intentional overdose with insulin preparations is rare. However, fatal consequences due to severe hypoglycemia could occur. Postmortem toxicology screening of insulin is a challenge, given the chemical characteristics of this protein and the difficulty of distinguishing between endogenous and exogenous insulin in blood. Here, we describe two cases of patients with diabetes using insulin and oral anti-diabetics. The main question in both cases was whether or not disturbance in glucose metabolism contributed to death. In case A, there was strong evidence that self-poisoning with insulin and subsequent hypoglycemia caused the death. However, this could not be confirmed due to lack of adequate forensic toxicology tests. In case B, no hypoglycemia was observed. Though, compared with case A, additional forensic examination was performed to investigate whether glycemic disturbances could have contributed to the death. In this report, we focus on the most appropriate analytical methods for the detection of exogenous insulin in the human body and give recommendations for toxicology testing of glucose levels and insulin in postmortem specimens.

18.
Forensic Sci Int Synerg ; 8: 100478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779309

RESUMO

Aim: Postmortem Computed Tomography (PMCT) is gradually introduced at forensic institutes. Image reconstruction software can increase diagnostic potential in CT by increasing distinction between structures and reduction of artifacts. The aim of this study was to develop and evaluate novel image reconstruction parameters for postmortem conditions, to increase image quality and diagnostic potential of CT scans. Method: Twenty PMCT scans of deceased hereof two in severe decay were subjected to four reconstruction techniques: a standard reconstruction algorithm, the detail reconstruction algorithm and two novel algorithms based on the standard algorithm, but with different Hounsfield settings. Image quality was evaluated by visual grading analysis (VGA) by four forensic radiologist observers. Results: The VGA did not prove that any of the reconstruction techniques were superior to the others. For standard and detail, the two pre-defined reconstruction algorithms, VGA scores were indiscernible and were superior to the equally indiscernible Hounsfield reconstructions on parameters translated into Sharpness and Low Contrast Resolution. The two alternative Hounsfield settings were superior with respect to Noise and Artifacts/Beam Hardening. Conclusion: The study elucidates the possiblity for multiple reconstructions specialized for PMCT conditions, to accommodate the special conditions when working with the deceased. Despite the lack of clear improvements in the tested reconstructions, this study provides an insight into some of the possibilities of improving PMCT quality using reconstruction techniques.

19.
Metabolites ; 14(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38786738

RESUMO

Japanese Brown (JBR) cattle have moderately marbled beef compared to the highly marbled beef of Japanese Black (JBL) cattle; however, their skeletal muscle properties remain poorly characterized. To unveil interbreed metabolic differences over the previous results, we explored the metabolome network changes before and after postmortem 7-day aging in the trapezius muscle of the two cattle breeds by employing a deep and high-coverage metabolomics approach. Using both capillary electrophoresis (CE) and ultra-high-performance liquid chromatography (UHPLC)-Fourier transform mass spectrometry (FT/MS), we detected 522 and 384 annotated peaks, respectively, across all muscle samples. The CE-based results showed that the cattle were clearly separated by breed and postmortem age in multivariate analyses. The metabolism related to glutathione, glycolysis, vitamin K, taurine, and arachidonic acid was enriched with differentially abundant metabolites in aged muscles, in addition to amino acid (AA) metabolisms. The LC-based results showed that the levels of bile-acid-related metabolites, such as tauroursodeoxycholic acid (TUDCA), were high in fresh JBR muscle and that acylcarnitines were enriched in aged JBR muscle, compared to JBL muscle. Postmortem aging resulted in an increase in fatty acids and a decrease in acylcarnitine in the muscles of both cattle breeds. In addition, metabolite set enrichment analysis revealed that JBR muscle was distinctive in metabolisms related to pyruvate, glycerolipid, cardiolipin, and mitochondrial energy production, whereas the metabolisms related to phosphatidylethanolamine, nucleotide triphosphate, and AAs were characteristic of JBL. This suggests that the interbreed differences in postmortem trapezius muscle are associated with carnitine/acylcarnitine transport, ß-oxidation, tricarboxylic acid cycle, and mitochondrial membrane stability, in addition to energy substrate and AA metabolisms. These interbreed differences may characterize beef quality traits such as the flavor intensity and oxidative stability.

20.
Med Leg J ; : 258172241230210, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690614

RESUMO

Post-mortem examination of the eye provides valuable forensic information yet is often overlooked. This brief review focuses on determining the cause/manner of death and post-mortem interval. External eye findings like corneal haziness and tache noire, combined with post-mortem changes in the iris, lens, retina and vitreous humour, can help estimate time since death. Ocular biometrics (iris/retinal scans) may facilitate identification. Age-related ocular changes can provide insights. The eye offers clues into personality (corneal tattooing, trichotillomania) and cause of death (petechiae in strangulation, retinal haemorrhages in abusive head trauma). Ocular trauma and underlying eye disease may be evident. Toxicology of vitreous humour can detect drugs/poisons. As a window into systemic disease and age-related changes, the eye aids pathology interpretations and, accordingly, post-mortem examinations have value. Ocular findings should not be overlooked in forensic examinations as they provide distinct information in determining cause/manner of death and post-mortem interval.

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