Forensic Science, Medicine and Pathology最新文献

The International Consortium Network/Orofacial Pain Special Interest Group focuses on temporomandibular disease diagnosis procedure guidelines as a reference iQAn this scope. Concerning this reference, the aim of this study was to comprehensively analyze injury and sequela frames within European and American approaches to personal damage. A quasiexperimental pilot study of Portuguese orofacial trauma cases in a medico-legal evaluation database was performed with an interrupted time series design. The clinical data were recorded following five criteria of TMJ diagnosis (jaw opening, pain, anatomical deficit, functional deficit, clinical sounds, and occlusal deficit) under three degrees of severity. The injury frame evaluation was recorded in the first-degree stage in all criteria. Pain, as a sequela, was the criterion present in 45% of the sample as spontaneous (20%) or stimulated (25%). Temporomandibular trauma damage evaluation emphasizes the accurate injury diagnosis and sequela framework. Orofacial trauma analysis should focus on the inclusion or exclusion of a TMD diagnosis. This study suggests revising the reference tables on personal damage, considering the inclusion of TMD and its categorization and impact.

Freezing and thawing have the potential to alter the gross and histologic appearance of tissues, causing damage to individual cells and disrupting the overall architecture. In forensic investigations, freezing and thawing can play a crucial role in cases of unknown cause of death. Perpetrators may use freezing preservation to conceal the body or obscure the time of death. Freezing can also occur naturally when a body is exposed to the elements, sometimes even leading to death itself. We present a case report involving an autopsy performed on an infant, who died of natural causes, after undergoing freezing and thawing. The objective of this study was to identify and discuss the histological artifacts observed in different tissues as a result of the freeze-thaw process. Histologically, the infant's tissues exhibited the most common features described in the literature. Ice crystal artifacts, characterized by expansion of the extracellular space and tissue clefts, were found in the heart, brain, liver, lungs, and kidneys. On the contrary, adipose tissue was not affected, likely due to the scarcity of water. Freeze-thaw artifacts should be taken into account whether a body is known to have been frozen or to add further data if found already defrosted.

All major definitions of sudden infant death syndrome (SIDS) specify that a careful pathological examination must be conducted which includes performance of a "complete" autopsy. Unfortunately, there is an increasing trend for cases to be classified as SIDS without fulfilling the required criteria, even including cases where an autopsy has not been performed. Failure to have an experienced pathologist with an understanding of SIDS involved in every step of the investigation and follow-up, with or without subsequent studies, may severely undermine the veracity of the diagnosis and the reliability of subsequent research conclusions.

DNA degradation in biological material needs to be better understood. Bloodstains on washed clothing are disturbed by washing procedures, sometimes transferred to other fabrics, often with latent bloodstains and usually with significantly degraded DNA. The samples (cotton fabric with bloodstains) are divided into six main groups, depending on the washing method regarding water temperature (95, 60, and 30 °C) and the detergent use. After completing the washing process, samples were stored for a certain period (1 day to 6 months) and subsequently analyzed. Analyses were performed using standard protocols and commercial kits to measure the remaining DNA quantity (concentration) and DNA degradation index in the processed samples. Our results revealed that the high washing temperature (60 and 95 °C) and the application of detergent have a synergic action on DNA degradation, while at 30 °C this effect is absent. Furthermore, the effect of detergent on accelerated DNA degradation is observed about a month after the washing. This delayed effect of detergent has no explanation in current literature data. To obtain optimal results from the bloodstains, we recommended that the period from the crime event and attempted cleaning by a perpetrator to the laboratory analysis should be less than 1 month.

Human or time resources can sometimes fall short in medical image diagnostics, and analyzing images in full detail can be a challenging task. With recent advances in artificial intelligence, an increasing number of systems have been developed to assist clinicians in their work. In this study, the objective was to train a model that can distinguish between various fracture types on different levels of hierarchical taxonomy and detect them on 2D-image representations of volumetric postmortem computed tomography (PMCT) data. We used a deep learning model based on the ResNet50 architecture that was pretrained on ImageNet data, and we used transfer learning to fine-tune it to our specific task. We trained our model to distinguish between "displaced," "nondisplaced," "ad latus," "ad longitudinem cum contractione," and "ad longitudinem cum distractione" fractures. Radiographs with no fractures were correctly predicted in 95-99% of cases. Nondisplaced fractures were correctly predicted in 80-86% of cases. Displaced fractures of the "ad latus" type were correctly predicted in 17-18% of cases. The other two displaced types of fractures, "ad longitudinem cum contractione" and "ad longitudinem cum distractione," were correctly predicted in 70-75% and 64-75% of cases, respectively. The model achieved the best performance when the level of hierarchical taxonomy was high, while it had more difficulties when the level of hierarchical taxonomy was lower. Overall, deep learning techniques constitute a reliable solution for forensic pathologists and medical practitioners seeking to reduce workload.

Deaths due to external causes, mainly suicide, are a severe public health problem in Brazil. Evidence shows that the tendency to impulsive behavior is exacerbated after alcohol consumption. The relationship between alcohol and suicide is poorly described in the medical literature. The study aims to analyze the relationship between victims' blood alcohol levels and suicides in some municipalities in Greater São Paulo, Brazil. We reviewed the data from the medical records of 805 necropsies performed at the Medical Legal Institute of Sao Paulo in Franco da Rocha, Brazil, from 2001 to 2017. The manner of death was established based on the result of police inquiry. Deaths due to suicide (n=41) were selected for the study. Descriptive statistics and Student t-test was applied when appropriate. The variables studied were sex, age, suicide mechanism, and blood alcohol level (BAC). In all cases we could not determine how much time the deceased consumed alcohol before suicide. Of the individuals analyzed, 85.36% were male, and 14.64% were female. The most prevalent age range for males was between 18 and 23 (19.5%). For females, it was between 12 and 23 years (33.2%). Most suicides (48.78%) were due to hanging, followed by self-poisoning (22.08%) and firearms (17.1%). 38 victims (92.68%) presented a positive BAC, over 0.3 mg/dl. The higher levels were in the group of suicide by hanging (2.3 mg/ml). Thus, alcohol intoxication is common among suicide victims, and it can contribute to the fatal outcome as a risk factor. Further studies are necessary for a better comprehension of the effect of alcohol on suicide victims.

Dimethyl sulfate (DMS) is a highly toxic chemical that appears innocuous and is commonly used as a methylating agent in industry. It can be readily absorbed leading to poisoning or death through the skin or mucous membranes of the respiratory tract in the process of production or transportation. Although there are some articles on treatment for DMS poisoning, reports of death resulting from acute fatal DMS poisoning are very rare. Here, we present a case of a 50-year-old Chinese man who died accidentally from DMS poisoning after he broke a plastic storage tank full of DMS during transportation. The patient complained of eye irritation. In addition, the corrosive damage could be seen in his corneas and skin. The autopsy revealed erosions and ulcers in the respiratory tract, as well as massive congestion, necrosis, edema, and pseudomembrane formation on the mucous layer of the trachea and main bronchi. Histopathological examination confirmed extensive pulmonary edema, multifocal hemorrhages, whole-cell swelling in the brain, as well as disintegration of the neuronal cell. We inferred that DMS poisoning caused the symptoms resulting from the production of methanol and sulfate through hydrolysis, including respiratory toxicity and neurotoxicity, and these symptoms had temporal continuity. Toxicological analysis revealed no DMS or methanol, but formic acid was detected in the brain, both qualitatively and quantitatively. In this report, we also present a retrospective study of 8 similar cases of DMS poisoning in literature in China, including some clinical data and autopsy information.

Pheniramine is an over-the-counter antihistamine drug. Its accessibility and low cost made it more popular among drug abusers in Pakistan. In this study, pheniramine was quantified in both conventional and alternative specimens of twenty chronic drug abusers, aged 16-50 years, who were positive for pheniramine in comprehensive toxicological screening for drugs by gas chromatography with mass spectral detection in positive electron impact mode. Pheniramine was extracted from biological specimens using solid phase extraction and liquid chromatography tandem mass spectrometry was employed for quantification. Chromatographic separation was carried out on a Poroshell120EC-18 (2.1 mm × 50 mm × 2.7 µm) column using water-acetonitrile in formic acid (0.1%) mobile phase in gradient elution mode with 500 μL/min flow rate. Positive electrospray ionization mode and multi-reaction monitoring with ion transitions m/z 241.3 → 195.8 and 167.1 for pheniramine and m/z m/z 247.6 → 173.1 for pheniramine-d6 were employed. The quantification method showed good linear ranges of 2-1000 ng/mL in blood, urine, and oral fluid; 2-1000 ng/mg in hair and 5-1000 ng/mg in nail with ≥ 0.985% coefficient of linearity. The retention time of pheniramine was 3.0 ± 0.1 min. The detection and lower quantification limits were 1 ng/mL and 2 ng/mL for blood, urine, oral fluid and hair whereas 2.5 ng/mg and 5 ng/mg for nail, respectively. Mean extraction recovery and ionization suppression ranged 86.3-95.1% and -4.6 to -14.4% in the studied matrices. Intra-day and inter-day precision were 4.1-9.3% and 2.8-11.2%, respectively. Pheniramine levels in specimens of drug abusers were 23-480 ng/mL in blood, 72-735 ng/mL in urine, 25-379 ng/mL in oral fluid, 10-170 ng/mg in hair and 8-86 ng/mg in nail specimens. Alternative specimens are of utmost significance in clinical and medico-legal cases. In this study, authors compared matrix-matched calibration curves to blood calibration curve and obtained results within ± 10%; thereby justifying the use of blood calibration curve for urine, oral fluid, hair, and nail specimens.

On roadways in the USA, the highest risk of death and the highest economic costs result from alcohol-impaired driving. The National Academies of Sciences Engineering and Medicine has the stated goal, "Lowering the BAC limits set by state law is an evidence-based, poplulation-level intervention with widespread impact that could help reach a bold goal: zero deaths from drinking and driving." I provide scientific, empirical evidence from around the world that: (a) documents benefits from lowering the per se blood alcohol from 0.08% to 0.05%; and (b) I support this conclusion with a novel, graphical comparison showing logically that failing to support 0.05% BAC is based on giving priority to non-scientific criteria.