Forensic case reports of Dermestes maculatus (Coleoptera: Dermestidae) in Santa Catarina state, Southern Brazil.

Only a few cases describing the activity of dermestids on human corpses have been reported in the literature. Dermestes maculatus is a cosmopolitan beetle associated with carcasses at different decomposition stages, usually colonizing skeletonized and mummified remains. In this study, we presented two forensic case reports of D. maculatus associated with human corpses in Santa Catarina State, southern Brazil. In the first case, a human corpse in an advanced stage of decomposition was found hanged in an outdoor urban area. In the other one, a mummified cadaver was found inside of a closed house. In this last case, larvae of D. maculatus were essential to estimate the minimum postmortem interval (PMI) for the first time in Scientific Police of Santa Catarina. Our records highlight the significance of necrophagous beetles in ecological succession and in estimating PMI in cases involving human remains and corpses in advanced stage of decomposition.

Development and intrapuparial characterization of Peckia (Euboettcheria) collusor (Curran and Walley, 1934) (Diptera: Sarcophagidae) for application in forensic entomology.

The family Sarcophagidae is very diverse in Brazil. Due to their living habits, they are the subject of many medical, veterinary, sanitary, and entomological studies. However, Sarcophagidae species are still poorly studied in forensic entomology, although they are frequently reported in carcasses and even human corpses. Thus, this study aims to identify and compare the developmental stages and intrapuparial morphological characteristics of Peckia (Euboettcheria) collusor to serve as an auxiliary tool in forensic entomology. The pupae collected after zero hour at 27 °C and 32 °C were sacrificed every three hours until the first 24 h and then every six hours until the emergence of the first adults, using 30 pupae each time, totaling 1560 for 27 °C and 1290 for 32 °C. The intrapuparial development time of this fly species under laboratory-controlled conditions was 288 h at 27 °C and 228 h at 32 °C. The 2820 pupae were analyzed according to temperature and classified into eight possible stages. This contributed to the selection of 16 key morphological characteristics to identify the age of the pupae. The identified intrapupal morphological characteristics have great potential to help researchers, experts, technical assistants, and forensic entomologists estimate the minimum post-mortem interval (minPMI) of cadavers.

Assessment of water relaxometry of meat under different ageing processes using time domain nuclear magnetic resonance relaxometry.

This study assessed water relaxometry of beef exposed to different ageing techniques by examining the inner and surface regions using time-domain nuclear magnetic resonance (TD-NMR) relaxometry. Beef strip loins were aged under vacuum (Wet), under vacuum using moisture absorbers (Abs), under vacuum using moisture absorbers and with mechanical tenderisation (AbsTend), or without any packaging (Dry). The ageing technique significantly influenced various meat parameters, including dehydration, total loss, and the moisture content of the meat surface. The transverse (T2) relaxation times provided a more sensitive indicator of the changes in meat water relaxometry than the longitudinal (T1) relaxation times. The Dry samples exhibited distinct differences in the T2 signals between the surface and inner regions of the meat. In particular, for the inner region, there were significant differences in signal areas between the Wet and Dry samples, and the Abs and AbsTend samples were positioned closely together between the Dry and Wet samples. The principal component analysis supported these findings: it indicated some differentiation among the ageing techniques in the score plot, but the differentiation was more pronounced when analysing the surface region. Additionally, there was a strong correlation between dehydration and the T2 values, leading to a clustering of the samples based on the ageing technique. The overlap between the Abs and AbsTend samples, situated between the Dry and Wet samples, suggests the potential of these treatments to produce meat with properties that are intermediate to Wet and Dry meat. Furthermore, tenderisation did not lead to greater dehydration.

Development of an innovative analytical method for forensic detection of cocaine, antidepressants, and metabolites in postmortem blood using magnetic nanoparticles.

Cocaine and antidepressants rank high globally in substance consumption, emphasizing their impact on public health. The determination of these compounds and related substances in biological samples is crucial for forensic toxicology. This study focused on developing an innovative analytical method for the determination of cocaine, antidepressants, and their related metabolites in postmortem blood samples, using unmodified commercial Fe3O4 nanoparticles as a sorbent for dispersive magnetic solid-phase extraction (m-d-SPE), coupled with liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis. An aliquot of 100 µL of whole blood and 5 µL of the internal standard pool were added to 30 mg of nanoparticles. The nanoparticles were separated from the sample using a neodymium magnet inserted into a 3D-printed microtube rack. The liquid was then discarded, followed by desorption with 300 µL of 1/1/1 acetonitrile/methanol/ethyl acetate. The sample was vortexed and separated, and 1.5 µL of the organic supernatant was injected into the LC-MS/MS. The method was acceptably validated and successfully applied to 263 postmortem blood samples. All samples evaluated in this study were positive for at least one substance. The most frequent analyte was benzoylecgonine, followed by cocaine and cocaethylene. The most common antidepressants encountered in the analyzed samples were citalopram and fluoxetine, followed by fluoxetine's metabolite norfluoxetine. This study describes the first report of this sorbent in postmortem blood analysis, demonstrating satisfactory results for linearity, precision, accuracy, and selectivity for all compounds. The method's applicability was confirmed, establishing it as an efficient and sustainable alternative to traditional techniques for forensic casework.

Biocultural and social determinants of ill health and early mortality in a New Mexican paediatric autopsy sample.

RESULTS: Hispanic children have higher odds of growth stunting than non-Hispanic White children. Native American children die younger and have higher odds of respiratory diseases and porous lesions than Hispanic and non-Hispanic Whites. Rural/urban location does not significantly impact age at death, but housing type does. Individuals who lived in trailers/mobile homes had earlier ages at death. When intersections between housing type and housing location are considered, children who were poor and from impoverished areas lived longer than those who were poor from relatively well-off areas. CONCLUSIONS: Children's health is shaped by factors outside their control. The children included in this study embodied experiences of social and ELS and did not survive to adulthood. They provide the most sobering example of the harm that social factors (structural racism/discrimination, socioeconomic, and political structures) can inflict.

Wildlife parasitology: sample collection and processing, diagnostic constraints, and methodological challenges in terrestrial carnivores.

Wild terrestrial carnivores play a crucial role as reservoir, maintenance, and spillover hosts for a wide parasite variety. They may harbor, shed, and transmit zoonotic parasites and parasites of veterinary importance for domestic hosts. Although wild carnivores are globally distributed and comprise many different species, some living in close proximity to human settlements, only a few studies have investigated parasites of wild terrestrial carnivores using non-specific techniques. Access to samples of wild carnivores may be challenging as some species are protected, and others are secretive, possibly explaining the data paucity. Considering the importance of wild carnivores' health and ecological role, combined with the lack of specific diagnostic methodologies, this review aims to offer an overview of the diagnostic methods for parasite investigation in wild terrestrial carnivores, providing the precise techniques for collection and analysis of fecal, blood, and tissue samples, the environmental impact on said samples, and the limitations researchers currently face in analyzing samples of wild terrestrial carnivores. In addition, this paper offers some crucial information on how different environmental factors affect parasite detection postmortem and how insects can be used to estimate the time of death with a specific highlight on insect larvae. The paper contains a literature review of available procedures and emphasizes the need for diagnostic method standardization in wild terrestrial carnivores.

Ethical Considerations in Post-Mortem Sperm Retrieval: A Comprehensive Review.

This comprehensive review delves into the moral and ethical dilemmas surrounding post-mortem sperm retrieval (PMSR) and its implications for creating new individuals. The paper examines the challenges posed by unusual requests for sperm retrieval from the deceased's widow and parents, as well as the broader socio-ethical considerations associated with PMSR. These requests have often been denied due to the absence of established laws and guidelines governing posthumous sperm retrieval and subsequent births, which were once deemed impossible. While some countries have implemented institutional policies to regulate its use to some extent, there remains a lack of standardized rules and procedures for the collection and retrieval of sperm after death. It is essential to introduce institutional guidelines to facilitate requests for assisted reproductive technology (ART) following successful sperm retrieval. Additionally, the development of PMSR legislation is necessary to ensure a proper balance between the moral rights and fundamental rights of the deceased, their family, and any current or future offspring, while providing adequate protection for all parties involved.

Entomological data from the first year of the Forensic Entomology Division formalization at Santa Catarina Scientific Police

ABSTRACT Forensic entomology has been developing in Brazil in recent years. In cases where traditional forensic methods cannot accurately determine the postmortem interval (PMI), entomological evidence can be crucial. In this novel study, we present the first results of the Forensic Entomology Division at Santa Catarina Scientific Police, southern Brazil, formally established in January 2022. From Jan 2022 to July 2023, minimum PMI was calculated based on entomological evidence in 34 cases. A total of 21 species of insects (16 species of Diptera belonging to 6 families and 5 species of Coleoptera belonging to 4 families) were collected from human bodies at different decomposition stages and in different types of environments. The most abundant and relevant species to estimate PMI were: Chrysomya albiceps (in 38% of the cases), followed by Hermetia illucens (18%), Oxelytrum discicolle (14%), Chrysomya megacephala (12%) and Peckia (Pantonella) intermutans (12%). Some species were reported for the first time colonizing human corpses in Santa Catarina and used for the first time to estimate minimum PMI in Brazil. Understanding the entomofauna present on a human corpse becomes an important tool in death investigations and is essential for forensic entomology applications. Our findings provide better understanding of entomological evidence from Santa Catarina State and have important implications for the advancement of forensic entomology in Brazil.

Willingness toward post-mortem body donation to science at a Mexican university: an exploratory survey.

BACKGROUND: Voluntary post-mortem donation to science (PDS) is the most appropriate source for body dissection in medical education and training, and highly useful for biomedical research. In Mexico, unclaimed bodies are no longer a legal source, but PDS is legally possible, although scarcely facilitated, and mostly ignored by the general population. Therefore, we aimed to evaluate the attitude and willingness for PDS and to identify a sociodemographic profile of people with willingness toward PDS. METHODS: A validated on-line survey was distributed by the convenience method via the social networks of a Catholicism-inspired, private university in northern Mexico. Frequency analyses of all variables and coded free comments were complemented with association studies. RESULTS: Although the responder cohort (n = 143) was too small and biased to be representative of the university community (n = 13,500), willingness to post-mortem organ donation was 90.7% and to PDS 70.7%. In this cohort, PDS willingness had the strongest association with mature age (> 40 years old; P, 0.0008). Among young adults, willingness to PDS was the lowest among volunteers from technical and business schools and the highest among those from the social sciences (P, 0.009). Respondents from the social sciences were also the most consistent between attitude and behavior with respect to organ donation. A free comment option revealed respondents were interested in the unusual taboo topic. CONCLUSIONS: A small, but sufficiently large proportion expressed willingness toward PDS. In our university cohort, which was biased in higher education and altruism, mature age and social interest were associated with PDS willingness.

Accuracy of ultrasound and visual inspection in antral follicular count in crossbred Holstein cows raised under grazing systems at high altitude.

The objective of this research was to investigate the diagnostic accuracy of post-mortem ultrasound in antral follicle count (AFC) determination and compare it with visual AFC in grazing crossbred Holstein cows, at high altitude in Ecuador. Pre-mortem blood from 80 cows was collected, and AFC and ovarian characteristics were analysed post-mortem by ultrasound and visual techniques. AFC counts were stratified as high, medium or low by terciles. Mean AMH concentration in pre-mortem blood was 280.1 ± 15.53 pg/mL. The AFC obtained by visual inspection (26.9 ± 9.49 follicles) was 23.8% higher than by ultrasound (20.5 ± 7.53 follicles) in all ovaries. Body condition score, age and weight of the cattle did not interact with the count technique. In the low AFC group, visual inspection and ultrasound provided similar AFC results. However, in the Medium- and High-AFC groups, AFC by ultrasound was 14.9% lower than AFC by visual inspection. We confirm that ultrasound can be used with great accuracy for AFC >3 mm (close to the resolution limit) in grazing crossbred Holstein cows at high altitude.

Ecological succession of blow flies (Diptera: Calliphoridae) in the decomposition of pig carcasses in Cerrado areas of Brazil.

This research aims to describe the process of ecological succession by associating the decomposition stages of pig carcasses with flies from the Calliphoridae family (Diptera). For this, 6 pig carcasses were exposed in Maranhão's Cerrado, utilizing metal cages with sawdust trays to catch immature specimens and "suspended traps" to capture adults. Adults of the Hemilucilia benoisti Séguy, and Hemilucilia townsendi Shannon species were only associated with the swelling stage. Chrysomya megacephala (Fabricius) was associated with 2 stages (black putrefaction and fermentation). The species Chloroprocta idioidea (Robineau-Desvoidy), Chrysomya albiceps (Wiedemann), Cochliomyia macellaria (Fabricius), and Lucilia eximia (Wiedemann) were associated with 4 of the 5 stages of decomposition, the latter being the only 1 associated with the initial stage. The larvae abandoned the carcasses to pupate from the second stage of decomposition, with L. eximia being the only 1 leaving the carcasses in the swelling stage, and C. albiceps the only 1 associated with both the fermentation and dry stages. Our findings indicate that calliphorid species can help forensic investigators estimine the post-mortem interval of cadavers in situations similar to those detailed in this study. Since there was a link between adult and immature species and certain stages, they can be used as indicators in future forensic investigations.

Mapping of SARS-CoV-2 in Waldeyer's lymphatic ring and visceral biopsies: the age and the illness duration's impact.

OBJECTIVE: To study the impact of age and the interval between disease diagnosis and death on the organotropism of SARS-CoV-2. METHOD: Patients underwent post-mortem biopsies from lungs, Waldeyer ring, heart, liver, kidneys and bone marrow between 2020‒2021. SARS-CoV-2 organotropism was mapped by using molecular RT-PCR analyses for SARS-CoV2 targeting the Envelope gene (E), the RNA Polymerase Gene (RdRp), and the Nucleocapsid gene (N). Statistical and linear regression analysis was performed to study the impact of age and illness duration in SARS-CoV-2 organotropism. RESULTS: We performed 158 postmortem biopsies in 21 patients, with a mean age of 76 years old. The mean interval between the diagnosis of the infection to the death was 23 days. The RNA of the SARS-CoV-2 was detected in 100% of lung biopsies, 76%‒82% of Waldeyer's ring biopsies, 55% of heart biopsies, 40% of kidney biopsies, 33% of liver and 25% of bone marrow biopsies. Patients who died before the day 9, presented extensive visceral dissemination of SARS-CoV-2 RNA. Most of the patients older than 80 years (90%) presented visceral dissemination of SARS-CoV-2 RNA, while among younger patients, only 3/11 patients presented visceral dissemination of the virus. The relationship between "age" and "illness duration" and multitropism of the virus was statistically significant (p<0.001). CONCLUSION: Disease interval and age were factors that were significantly associated with RT-PCR positive results in multiple organs. Critical COVID-19 patients have multiorganic viral dissemination in early stages. In the critical older patients, multiorganic viral dissemination is the rule.

Post-mortem toxicological analysis of cocaine: main biological samples and analytical methods.

This scoping review intends to identify the most used analytical methods and biological samples in the post-mortem forensic toxicological analysis of cocaine and its metabolites. A scoping review was performed based on the question "What are the analytical methods and types of biological samples most frequently used to identify and quantify cocaine in post-mortem forensic toxicology?" The studies were selected from five databases and, after exclusions, the data were tabulated, analyzed, and reported. Twenty-one articles published between 2012 and 2022 were filtered from five different databases to be studied. The collected data indicate that the most used biological samples were blood and hair. The most used sample preparation technique was solid phase extraction, while the most mentioned chromatography method was liquid chromatography with mass spectrometry. This review presents and discusses the state of the art regarding methods for the detection sensitivity spectrum, why limits of quantification are so important for these methods, and what are the most suitable biological samples to be utilized in each case. Cocaine and metabolites are important in forensic toxicologic post-mortem analysis. However, there is little concern in the development of miniaturized and automated sample preparation in this field. Besides, there is not enough understanding of post-mortem redistribution, tolerance, drug-drug interactions, and pre-existing medical conditions.

Estudio retrospectivo sobre equinococosis quística en animales de granja en el norte de Türkiye

RESUMEN Objetivo. Este estudio se realizó retrospectivamente para evaluar el estado de equinococosis quística de los animales de granja, analizando las muestras enviadas al Instituto de Control Veterinario de Samsun de la República de Türkiye, Ministerio de Agricultura y Silvicultura, entre el Enero de 2016 y el Diciembre de 2022. Materiales y Métodos. Un total de 818 ovejas, 160 cabras y 990 materiales de necropsia de ganado bovino se examinaron macroscópicamente e histopatológicamente de acuerdo con las directrices de la Organización Mundial de Sanidad Animal (WOAH). Los quistes se detectaron en 61 materiales de todos los materiales examinados. Resultados. Se encontró que la tasa de positividad de equinococosis quística total en animales de granja era del 3,1% en el norte de Türkiye. Se detectaron quistes en al menos uno de los hígados y pulmones. Se detectó en hígado en 24 casos (39.3%), pulmón en 23 casos (37.7%) y tanto pulmón como hígado en 11 casos (18%). Además, se encontraron quistes tanto en pulmón como en bazo (1 caso), riñón e hígado (1 caso) y corazón e hígado (1 caso). La tasa de positividad fue mayor en ovejas que en otros rumiantes, y la diferencia con otras especies de rumiantes fue estadísticamente significativa. (p<0.001). Se encontró que la diferencia entre las tasas de prevalencia por años era estadísticamente significativa (p=0.001). Conclusiones. Türkiye se define como una región altamente endémica para Echinococcus granulosus y Echinococcus multilocularis. La vigilancia debe realizarse regularmente para implementar programas de control. La información presentada en este estudio contribuirá a obtener una idea sobre el estado de la equinococosis quística en el ganado en el norte de Türkiye y al desarrollo de estrategias de prevención y control.

ABSTRACT Objective. This study was conducted retrospectively to assess the cystic echinococcosis status of farm animals from the samples sent to Samsun Veterinary Control Institute of the Republic of Türkiye, Ministry of Agriculture and Forestry, between January 2016 and December 2022. Materials and Methods. A total of 818 sheep, 160 goats, and 990 cattle necropsy materials were examined macroscopically and histopathologically according to World Organisation for Animal Health (WOAH) guidelines. Cysts were detected in 61 of examined materials. Results. The rate of total cystic echinococcosis positivity in farm animals was found to be 3.1% in northern Türkiye. Cysts were detected in at least one of the liver and lungs. It was detected in the liver in 24 cases (39.3%), the lung in 23 cases (37.7%), and both the lung and liver in 11 cases (18%). In addition, cysts were found in both of lung and spleen (1 case), kidney and liver (1 case), and heart and liver (1 case). The positivity rate was higher in sheep than in other ruminants, and the difference with other ruminant species was statistically significant. (p<0.001). The difference between prevalence rates by years was found to be statistically significant (p=0.001). Conclusion. Türkiye is defined as a highly endemic region for Echinococcus granulosus and Echinococcus multilocularis. Surveillance should be done regularly to implement control programs. The information presented in this study will contribute to gaining an idea about the status of cystic echinococcosis in livestock in northern Türkiye and to the development of prevention and control strategies.

Seasonal distribution of Calliphoridae and Mesenbrinellidae (Diptera) associated with the decomposition of a clothed animal model in a forest reserve in the Central Amazon.

We evaluated the effects of seasonality on the richness and abundance of dipterans of the families Calliphoridae and Mesembrinellidae associated with the decomposition of a clothed Large White swine Sus scrofa domesticus(Artiodactyla: Suidae) carcass. Experiments were carried out in less rainy, rainy, and intermediate periods between 2010 and 2011 at Reserva Florestal Ducke, Manaus, Amazonas. Two pig carcasses, each weighing approximately 40 kg, were used in each period. A total of 63,872 individuals of 18 species of Calliphoridae and Mesembrinellidae were collected. The abundance and richness of these dipteran families were influenced by the interaction between period and decomposition stage. The compositions of the Calliphoridae and Mesembrinellidae assemblages differed among periods, with the fauna of the less rainy period being less similar to those of the intermediate and rainy periods than they were to each other. Three species were selected as indicators for the less rainy period, namely Paralucilia pseudolyrcea (Mello, 1969) (Diptera, Calliphoridae), Paralucilia nigrofacialis (Mello, 1969) (Diptera, Calliphoridae), and Eumesembrinella randa (Walker, 1849) (Diptera,Mesembrinellidae) while Chloroprocta idioidea (Robineau-Desvoidy, 1830) (Dipetra, Calliphoridae) was selected as an indicator species for the rainy period; no taxon was selected as an indicator of the intermediate period. Among decomposition stages, only fermentation and black putrefaction had indicator taxa, with Hemilucilia souzalopesi Mello, 1972 (Diptera, Calliphoridae and Chysomya putoria(Wiedemann, 1830) (Diptera, Calliphoridae), respectively. Clothes did not prevent the laying of eggs and became a kind of protection for immature stages. The clothed model presented a delay in decomposition compared to other studies developed in the Amazon region.

A miRNome analysis at the early postmortem interval.

The postmortem interval (PMI) is the time elapsing since the death of an individual until the body is examined. Different molecules have been analyzed to better estimate the PMI with variable results. The miRNAs draw attention in the forensic field to estimate the PMI as they can better support degradation. In the present work, we analyzed the miRNome at early PMI in rats' skeletal muscle using the Affymetrix GeneChip™ miRNA 4.0 microarrays. We found 156 dysregulated miRNAs in rats' skeletal muscle at 24 h of PMI, out of which 84 were downregulated, and 72 upregulated. The miRNA most significantly downregulated was miR-139-5p (FC = -160, p = 9.97 × 10-11), while the most upregulated was rno-miR-92b-5p (FC = 241.18, p = 2.39 × 10-6). Regarding the targets of these dysregulated miRNAs, the rno-miR-125b-5p and rno-miR-138-5p were the miRNAs with more mRNA targets. The mRNA targets that we found in the present study participate in several biological processes such as interleukin secretion regulation, translation regulation, cell growth, or low oxygen response. In addition, we found a downregulation of SIRT1 mRNA and an upregulation of TGFBR2 mRNA at 24 h of PMI. These results suggest there is an active participation of miRNAs at early PMI which could be further explored to identify potential biomarkers for PMI estimation.

Viable SARS-CoV-2 Omicron sub-variants isolated from autopsy tissues.

Introduction: Pulmonary and extrapulmonary manifestations have been described after infection with SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19). The virus is known to persist in multiple organs due to its tropism for several tissues. However, previous reports were unable to provide definitive information about whether the virus is viable and transmissible. It has been hypothesized that the persisting reservoirs of SARS-CoV-2 in tissues could be one of the multiple potentially overlapping causes of long COVID. Methods: In the present study, we investigated autopsy materials obtained from 21 cadaveric donors with documented first infection or reinfection at the time of death. The cases studied included recipients of different formulations of COVID-19 vaccines. The aim was to find the presence of SARS-CoV-2 in the lungs, heart, liver, kidneys, and intestines. We used two technical approaches: the detection and quantification of viral genomic RNA using RT-qPCR, and virus infectivity using permissive in vitro Vero E6 culture. Results: All tissues analyzed showed the presence of SARS-CoV-2 genomic RNA but at dissimilar levels ranging from 1.01 × 102 copies/mL to 1.14 × 108 copies/mL, even among those cases who had been COVID-19 vaccinated. Importantly, different amounts of replication-competent virus were detected in the culture media from the studied tissues. The highest viral load were measured in the lung (≈1.4 × 106 copies/mL) and heart (≈1.9 × 106 copies/mL) samples. Additionally, based on partial Spike gene sequences, SARS-CoV-2 characterization revealed the presence of multiple Omicron sub-variants exhibiting a high level of nucleotide and amino acid identity among them. Discussion: These findings highlight that SARS-CoV-2 can spread to multiple tissue locations such as the lungs, heart, liver, kidneys, and intestines, both after primary infection and after reinfections with the Omicron variant, contributing to extending knowledge about the pathogenesis of acute infection and understanding the sequelae of clinical manifestations that are observed during post-acute COVID-19.

Evaluation of multi-channel phase reconstruction methods for quantitative susceptibility mapping on postmortem human brain.

Quantitative Susceptibility Mapping (QSM) is an established Magnetic Resonance Imaging (MRI) technique with high potential in brain iron studies associated to several neurodegenerative diseases. Unlike other MRI techniques, QSM relies on phase images to estimate tissue's relative susceptibility, therefore requiring a reliable phase data. Phase images from a multi-channel acquisition should be reconstructed in a proper way. On this work it was compared the performance of combination of phase matching algorithms (MCPC3D-S and VRC) and phase combination methods based on a complex weighted sum of phases, considering the magnitude at different powers (k = 0 to 4) as the weighting factor. These reconstruction methods were applied in two datasets: a simulated brain dataset for a 4-coil array and data of 22 postmortem subjects acquired at a 7T scanner using a 32 channels coil. For the simulated dataset, differences between the ground truth and the Root Mean Squared Error (RMSE) were evaluated. For both simulated and postmortem data, the mean (MS) and standard deviation (SD) of susceptibility values of five deep gray matter regions were calculated. For the postmortem subjects, MS and SD were statistically compared across all subjects. A qualitative analysis indicated no differences between methods, except for the Adaptive approach on postmortem data, which showed intense artifacts. In the 20% noise level case, the simulated data showed increased noise in central regions. Quantitative analysis showed that both MS and SD were not statistically different when comparing k = 1 and k = 2 on postmortem brain images, however visual inspection showed some boundaries artifacts on k = 2. Furthermore, the RMSE decreased (on regions near the coils) and increased (on central regions and on overall QSM) with increasing k. In conclusion, for reconstruction of phase images from multiple coils with no reference available, alternative methods are needed. In this study it was found that overall, the phase combination with k = 1 is preferred over other powers of k.

Effect of diazinon (organophosphate) on the composition and succession of Calliphoridae assemblages in rabbit carcasses in the Eastern Amazon.

Fatal poisonings with diazinon may occur both accidentally or intentionally in suicide cases. Forensic entomotoxicology can aid in understanding these deaths by detecting and analyzing the interference of toxic substances in the biology of necrophagous insects. Hence, this study sought to evaluate diazinon's effect on the composition and succession of calliphorid species in the tropical savannas of the Amazon. Nine rabbit carcasses were divided into three groups: one control and two diazinon treatments (100 mg/kg and 300 mg/kg); each group had three replicates. Three fragments of the Amazon tropical savanna were selected for the experiments. Daily collections of adult and immature calliphorids were performed. Five decomposition stages were observed: fresh, bloated, active decay co-occurring, advanced decay, and dry. Eight species of Calliphoridae were identified among the collected adults: Chloroprocta idioidea (0.1%), Chrysomya albiceps (58.3%), Chrysomya megacephala (14.2%), Chrysomya putoria (2.6%), Cochliomyia hominivorax (1.3%), Cochliomyia macellaria (0.5%), Lucilia eximia (19.8%), and Paralucilia paraensis (3.3%). The adult specimens in the control group with the highest abundance were observed only from the advanced decay stage onward. In the dry stage, abundance was higher in control than in treated carcasses. From the sampled 941 Calliphorid immatures, three species were identified: C. albiceps (76,3%), C. putoria (1%), and L. eximia (22,7). The number of immatures was higher in control than in treated carcasses. Therefore, diazinon interferes with the putrefaction timeframe in carcasses, slowing the decomposition stages and affecting their colonization by immature forms of Calliphoridae.

Histological changes in lingual striated muscle tissue of human cadavers to estimate the postmortem interval.

Although there are physiological methods to determine the postmortem interval (PMI), interval forensic histopathology can be applied to obtain accuracy. The aim was to describe the histological changes in human lingual striated musculature at different PMI. Seven groups were formed according to increasing PMI of 6, 12, 24, 48, 72, 96 and 120 h postmortem (PM). Each group was made up of 16 samples of tongues from each cadaver. The samples were fixed in buffered formaldehyde at 10% and processed for embedding in paraplast. Section 5 µm thick were cut and dyed with H&E for analysis. The study was approved by the Bioethics Committee of the Universidad San Francisco de Quito, Ecuador. The histological changes in the striated muscle cells of the tongue were associated with the different PMI. From 6 to 24 h PM, there were initial changes in the cellular and nuclear morphology. At 48 h PM, at least 50% of the samples presented poorly conserved and reduced muscle striations. At 72 h PM, 100% of the cases presented myofibers with altered morphology, cytoplasmic vacuoles (93.75%), edema (68.55%) and pyknosis (93.75%). At 96 and 120 h PM, the myofibers presented pyknotic nuclei, and they were absent in the rest. The changes in the histology of the human lingual striated muscle make it possible to estimate the PMI, either in the early phase (0-72 h) or the late phase (92-120 h). However, further research is needed to verify, refine and expand on these results.