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The objective of this exploratory study was to assess the changes on lipidome and metabolome profiling of Longissimus lumborum bull muscle with different ultimate pH (pHu) and aging periods. The bull muscles classified as normal, intermediate, or high pHu were collected from a Brazilian commercial slaughterhouse, cut into steaks, individually vacuum-packaged, and aged for 3 days (3-d) or 21 days (21-d) at 2 °C. Muscle extracts were analyzed for the profiles of both lipids, by mass spectrometry (via direct flow-injection), and metabolites, by nuclear magnetic resonance, with downstream multivariate data analysis. As major results, pairwise comparisons identified C12:0 and C14:0 acylcarnitines as potential biomarkers of the intermediate pHu-muscle, which are related to lipid catabolism for alternative energy metabolism and indicate less protein breakage postmortem. Interestingly, the concentration of arginine at early postmortem aging (3-d) may influence the previously reported improved tenderness in normal and high pHu-muscles. Moreover, upregulation of fumarate, formate, and acetate with increased pHu muscle at 21-d aging indicate more intense tricarboxylic acid cycle, amino acid degradation, and pyruvate oxidation by reactive oxygen species, respectively. These three compounds (fumarate, formate, and acetate) discriminated statistically the muscle with high pHu at 21-d aging. The normal pHu-muscle showed higher concentrations of glycogenolysis and glycolysis metabolites, including glucose, mannose, and pyruvate. Hence, our results enhance knowledge of postmortem biochemical changes of beef within different pHu groups aged up to 21 days, which is essential to understand the mechanisms underpinning bull meat quality changes.

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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.

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This study aimed to evaluate for the first time the temporal dynamic changes in early postmortem proteome of normal and high ultimate pH (pHu) beef samples from the same cattle using a shotgun proteomics approach. Ten selected carcasses classified as normal (pHu < 5.8; n = 5) or high (pHu ≥ 6.2; n = 5) pHu beef from pasture-finished Nellore (Bos taurus indicus) bulls were sampled from Longissimus thoracis muscle at 30 min, 9 h and 44 h postmortem for proteome comparison. The temporal proteomics profiling quantified 863 proteins, from which 251 were differentially abundant (DAPs) between high and normal pHu at 30 min (n = 33), 9 h (n = 181) and 44 h (n = 37). Among the myriad interconnected pathways regulating pH decline during postmortem metabolism, this study revealed the pivotal role of energy metabolism, cellular response to stress, oxidoreductase activity and muscle system process pathways throughout the early postmortem. Twenty-three proteins overlap among postmortem times and may be suggested as candidate biomarkers to the dark-cutting condition development. The study further evidenced for the first time the central role of ribosomal proteins and histones in the first minutes after animal bleeding. Moreover, this study revealed the disparity in the mechanisms underpinning the development of dark-cutting beef condition among postmortem times, emphasizing multiple dynamic changes in the muscle proteome. Therefore, this study revealed important insights regarding the temporal dynamic changes that occur in early postmortem of high and normal muscle pHu beef, proposing specific pathways to determine the biological mechanisms behind dark-cutting determination.

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Peckia (Peckia) chrysostoma (Wiedemann, 1830) (Diptera: Sarcophagidae) is a colonizer of cadavers in the Neotropical Region. Nevertheless, data on development for the P. (P.) chrysostoma (e.g., instar duration) and behavioral strategies used by the species for locating and colonizing a corpse are scant. We aimed to explore bionomic and reproductive aspects of the flesh fly P. (P.) chrysostoma, and in this article we: (a) provide quantitative data on the life cycle of P. (P.) chrysostoma; (b) present bionomic measurements (length and weight) of larvae and pupae; (c) describe intrauterine egg and larvae development; and (d) analyze the ovo/larviposition behavior by gravid females. Females showed ovaries with discernible eggs and larvae between 8 and 10 days (x̅ = 23.3 eggs/female). This study reports the first observation of egg deposition, an atypical behavior for the species. The average development time for immature stages was 22.24 h and 21.36 h for 1st and 2nd respectively, and 3rd showed an average development time of 80.47 h. Pupa had the longest duration (x̅ = 295.69 h). A direct increase was observed in weight (P < 0.05) and length (P < 0.05) throughout time. The average survival time of males and females is approximately 30 days. This study expands the knowledge on P. (P.) chrysostoma, such as facultative ovoviviparity under laboratory conditions and the life cycle, which may benefit future studies for accuracy in entomology-based estimation of minimum post-mortem interval (min PMI).

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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.

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La coloración rosa de los dientes puede originarse por diferentes factores. En el ámbito forense se ha descrito al fenómeno denominado post mortem pink teeth como un signo asociado a muertes violentas de etiología diversa. En la práctica clínica también es posible observar pacientes con dientes rosados, fre-cuentemente ocasionados por traumatismos o iatro-genia proveniente de ortodoncia, cuyo mecanismo de producción obedece a distintas etiopatogenias, destacándose las reabsorciones dentinarias inter-nas, cemento-dentinarias externas y calcificaciones dentinarias. El presente artículo expone el caso de un individuo adulto con antecedente de trauma óseo-dentario por accidente vial que, luego de un prolon-gado tiempo, asiste al Servicio de Urgencias Odon-tológicas y Orientación de Pacientes de la Facultad de Odontología de la Universidad de Buenos Aires, en donde se le detecta, a modo de hallazgo exploratorio, una ostensible coloración rosada en el canino infe-rior derecho. La situación motivó un pormenorizado abordaje clínico y radiográfico, indagando respecto a los probables factores que intervinieron en su ge-neración y desarrollo (AU)

The pink coloration of the teeth can be caused by dif-ferent factors. In the forensic field, the phenomenon called post mortem pink teeth has been described as a sign associated with violent deaths of various etiology. In clinical practice, it is also possible to ob-serve patients with pink teeth, frequently caused by trauma or iatrogenesis from orthodontics, whose production mechanism is due to different etiopatho-genesis, highlighting internal dentin resorption, ex-ternal cemento-dentinal resorption and dentin calci-fications. This article presents the case of an adult individual with a history of bone-dental trauma due to a road accident who, after a long time, attends the Dental Emergency and Patient Guidance Service of the Faculty of Dentistry of the University of Bue-nos Aires, where an ostensible pink coloration was detected in the lower right canine as an exploratory finding. The situation motivated a detailed clinical and radiographic approach, inquiring about the probable factors that intervened in its generation and development (AU)

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La identificación humana genera continuos desafíos técnicos y científicos para los equipos de expertos forenses en sus múltiples contextos de intervención. Uno de los más complejos, está representado por el hallazgo de cadáveres quemados o carbonizados, donde las huellas dactilares resultan inviables. En tales situaciones, los tejidos de la cavidad oral han demostrado elevada tolerancia a la injuria térmica, aportando información decisiva, muchas veces com-plementada por estructuras protésicas recupera-das del occiso. El presente artículo reporta dos ca-sos donde las prótesis dentales acrílicas y de cromo cobalto exhibieron notable indemnidad pese a la gran pérdida orgánica sufrida por los cuerpos de las víc-timas ante la acción vulnerante del fuego, otorgando valor probatorio para contribuir en el establecimien-to de su identidad (AU)

Human identification generates continuous technical and scientific challenges for teams of forensic experts in their multiple contexts of intervention. One of the most complex is represented by the discovery of burned or charred corpses, where fingerprints are unviable. In such situations, the tissues of the oral cavity have shown high tolerance to thermal injury, providing decisive information, often complemented by prosthetic structures recovered from the deceased. This article reports two cases where the acrylic and cobalt chrome dental prostheses presented notable indemnity despite the great organic loss suffered by the bodies of the victims before the damaging action of fire, granting probative value to contribute to the establishment of their identity (AU)

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Proteomics has been widely used to study muscle biology and meat quality traits from different species including beef. Beef proteomics studies allow a better understanding of the biological processes related to meat quality trait determination. This study aimed to decipher by means of two-dimensional electrophoresis (2D-PAGE), mass spectrometry and bioinformatics the changes in post-mortem muscle with a focus on proteins differentially expressed in the Longissimus thoracis (LT) muscle of immunocastrated young heifers and steers. Carcass traits, chemical composition, pH, instrumental color (L*, a*, b*), cooking loss and Warner-Bratzler shear force (WBSF) of meat from F1 Montana-Nellore cattle were also evaluated. Backfat thickness (BFT) and intramuscular fat content (IMF) were 46.8% and 63.6% higher in heifers (p < 0.05), respectively, while evaporation losses (EL) were 10.22% lower compared to steers. No differences (p > 0.05) were observed for tenderness evaluated by WBSF (3, 10, and 17 days post-mortem), pH, and color traits (L*, a* and b*) between the experimental groups. The study revealed several proteins to be differentially expressed proteins in heifers compared steers (p < 0.05). In heifers, proteins involved in nutrient transport (TF, ALB, and MB), energy metabolism (ALDOA, GAPDH, and PKM), and oxidative stress and response to stress (HSPA8 and CA3) were associated with a greater BFT and IMF deposition. The higher expression of these proteins indicated greater oxidative capacity and lower glycolytic activity in the LT muscle of heifers. In steers, there was greater abundance of protein expression related to muscle contraction and proteins of structure (ACTA1, TPM2 and TNNT3), energy metabolism (ENO1, ENO3, PYGM, PGM1 and TPI1) and ATP metabolism (ATP5F1B, PEBP1 and AK1), indicating greater glycogenolysis in LT muscle, suggesting a shift in the glycolytic/oxidative fibers of steers.

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Introducción: El "diente rosado" es un fenómeno post mortem. Se caracteriza por una tonalidad rosa, rojiza y hasta púrpura, que puede observarse en los dientes. Su primera referencia se remite a 1829, cuando Thomas Bell lo describió, y genera polémica desde hace casi dos siglos. La temática plantea varias interrogantes: ¿sería más lógico nombrarlo "red teeth" o "purple teeth"?, ¿qué provoca esa tonalidad más intensa?, ¿la coloración rosada indica determinada causa de muerte?, ¿queda para siempre o puede desaparecer por diversos factores? Objetivo: Describir los indicadores de que el "diente rosado" o "pink teeth" pueda aún ser considerado un elemento importante para la investigación forense actual. Comentarios principales: Luego de la experiencia acumulada con los casos trabajados durante los últimos 20 años y la revisión bibliográfica realizada, se evidencia que el fenómeno aparece sobre todo en las piezas dentales anteriores y premolares monorradiculares. Además, puede verse tanto ante mortem como post mortem. Por causas diferentes el post mortem necesita de varios días para instaurarse y es un evento tafonómico, evidenciable tanto en muertes violentas como naturales, aunque la variación en su tonalidad depende de diversos factores. Consideraciones globales: Teniendo en cuenta la experiencia obtenida por los autores, y lo referido en la bibliografía sobre el tema, se evidencia que este signo, fenómeno o hallazgo (al aclararse las interrogantes planteadas) aún puede ser muy significativo y orientador en el contexto forense actual(AU)

Introduction: "Pink teeth" are a post-mortem phenomenon characterized by a rose, reddish and even purple shade of color which may be observed in teeth. Their first reference dates back to 1829, when Thomas Bell described them. They have been a topic of debate for almost two centuries. The subject poses several questions: Would it be more logical to name them "red teeth" or "purple teeth"? What causes the increase in color intensity? Does the pink shade signal a specific cause of death? Does it remain forever or may it disappear for a variety of reasons? Objective: Describe the indicators that "pink teeth" may still be considered an important element in current forensic research. Main remarks: Based on the experience gathered from the cases analyzed in the last 20 years and the bibliographic review conducted, it is evident that the phenomenon appears mainly in anterior teeth and single-rooted premolars. On the other hand, pink teeth may be observed ante mortem as well as post mortem. For a number of reasons, post mortem pink teeth take several days to form, and they are a taphonomic phenomenon, present in violent as well as natural deaths, though their change in tone depends on various factors. General considerations: Founded on the experience obtained by the authors and the bibliography about the topic, it is evident that this sign, phenomenon or finding (upon clarification of the questions posed) may still be very significant and enlightening in the current forensic context(AU)

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Given the growing demands for standardization of procedures for collection, preservation, and identification of insect specimens, this study aimed to identify how forensic entomology is used in Brazil and the perceptions of professionals involved in this process. We conducted: (1) bibliometric survey of the scientific production of forensic specialists from 2001 to 2020; (2) questionnaire applied to forensic professionals to verify their perceptions about the use of entomological evidence in practice. An increase in publications on Forensic Entomology was noticed in the last 5 years, mainly in the South and Northeast regions. Of the 82 respondents to the questionnaire, 62.8% deal with cadavers at least once a week, but 89.0% of the professionals who examine cadavers weekly find less than 10.0% colonized by insect larvae. Using entomological evidence to estimate PMI was mentioned by only 36.6% of the professionals. Most respondents stated no procedures related to collecting, handling, or identifying necrophagous insects in their daily practice. Regarding the chain of custody, 64.6% said they were aware of the changes in the regulations involving the collection and maintenance of forensic evidence. We emphasize the importance of collaboration between scientists at universities and crime scene examiners. Although the use of entomological evidence in criminal investigations in Brazil is still scarce, a growing interest in this area can be detected among forensic experts.

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