Revista Espanola de Medicina Legal最新文献

Introduction

Sex estimation is a fundamental aspect of forensic work as a mandatory step for the identification of human remains of unknown origin. The methodological analysis of the dentition as a sexual estimator is important due to its high degree of preservation. Considering the need for specific information regarding the potential of dentition for sex estimation in forensic cases from Argentina, the aim of this study is to evaluate the proposal previously developed by Luna (2019) in a local sample of human skeletal remains.

Materials and methods

A sample of 152 permanent canines belonging to 98 individuals of both sexes was selected- The individuals belong to the Prof. Dr. Rómulo Lambre osteological collection (La Plata, Argentina). Luna's proposal (2019) was applied to estimate sex from canine crown and neck metrics, which considers direct measurements and different types of discriminant functions and logistic regressions.

Results

Only the cervical mesiodistal diameter showed acceptable results (> 75%) for sex estimation. Moreover, discriminant function 1 showed a posteriori probabilities of correct classifications greater than 0.75 and logistic regressions 1 and 3 offered acceptable overall results.

Conclusions

This proposal based on the metric recording of permanent canines constitutes an adequate methodological alternative in situations in which the diagnostic bone elements of sex are deteriorated or absent.

Introduction

Involuntary admissions due to mental disorders occur with relative regularity in hospital admission units in our country. This work will study the socio-demographic and clinical characteristics found in relation to this type of patients, in order to have more information, both clinical and legal, with which to work and perform a better function, administration of resources and development of necessary skills in these situations.

Material and methods

Retrospective descriptive observational study, in which different variables will be analyzed, previously selected, present in the population of psychiatric patients involuntarily admitted to the Doctor Negrín Hospital in a period of 2 years, 2019 and 2020, thus determining, the degree of prevalence of each of them.

Results

Among the variables most associated with involuntary admission are, being a man, in the fourth decade of life, single, without children, or employment, with a diagnosis of major psychotic or affective disorder who has most likely abandoned treatment.

Discussion

It would be advisable to carry out a special follow-up of patients who meet the profile described above in order to minimize involuntary occurrence. It is necessary to develop educational, follow-up and adherence programs within the reach of the population of psychiatric patients in order to minimize the need for involuntary admissions in our environment.

Y-chromosome-specific short tandem repeat (Y-STR) markers reside on the non-recombinant portion of the Y chromosome, their inheritance is paternal, they are not detectable in female DNA. These properties make Y-STRs a useful tool in forensic investigations such as sexual assault, parenting, and other violent crimes; likewise they are also useful in genealogical and evolutionary studies. The objective of the research is to expand the scientific evidence of the distribution by region or country of the Y sex chromosome haplotypes. Similar studies in Peruvian populations are scarce due to the smaller number of Y-STR polymorphisms frequently used in Forensic and Population Genetics.

Material and method: In the investigation, 141 DNA samples from the jungle of Peru were analyzed, of which comprised of 104 samples from Iquitos region (Loreto), 29 samples from Awajun (Amazonas) and 8 samples from Tambopata (Madre de Dios). The samples were processed using direct PCR with the Yfiler™ Plus PCR Amplification kit for 27 STRs, the amplified products were analyzed by capillary electrophoresis on the Applied Biosystem™ 3500XL Genetic Analyzer, and the data obtained was imported into the GeneMapper® ID-X v1.5 software to generate the genetic profiles. With the results obtained, the statistical analysis and the population structure were carried out.

Results: Of the 141 samples, 106 unique haplotypes were observed. Gene diversities for each Y-STR marker ranged from 0.317 to 0.919. The haplotype diversity for the total sample was 0.9906. This study supports that the Y-STR haplotypes in this population are highly polymorphic in the analyzed population and, therefore, are very useful in forensic studies of human identification, as well as in population genetics when investigating groups or individuals from Latin America.

Introduction

The aim of this paper is to analyze the characteristics of the victims and the circumstances of sexual violence related with the risk of physical lesions, as well as to determine the frequency and severity of the injuries.

Material and methods

Descriptive study of 702 cases of sexual assault attended at the Institute of Legal Medicine and Forensic Sciences of Alicante between the years 2016–2020. A comparative study was carried out between victims with and without injuries, to identify the variables associated to their presentation.

Results

314 victims attended showed physical injuries (44,8%). Profile of the victims with injuries were women (95.5%), aged 18 to 27 years (31.3%), and previous alcohol consumption (50%). Injuries physical were mainly extragenital (38.6%), anogenital (15%), or both, and most cases were mild in severity (97.5%). Recovery was less to one week (83.4%) and without aftermath (97.1%). When the victim showed aftermath (9 cases), the most frequent were psychological type (1.6%).

Conclusions

Physical injuries in sexual violence is related with circumstances of victim vulnerability: women, age between 18 to 27 years, and previous alcohol consumption.

Our study shows that anogenital lesions are absent in a significative number of victims of sexual assault, so this absence cannot exclude sexual violence. The lesions found are mild in severity, and the absence of physical aftermath in most of the victims may be conditioned by the scarce follow-up of them.

Introduction

The extraction techniques of deoxyribonucleic acid (DNA) from old bone samples are based on the use of complex methodologies, which deal with the degradation of the sample, the low amount of DNA and the presence of inhibitors that can be extracted simultaneously.

Objective

To compare the efficiency in obtaining DNA from the methods: organic extraction, commercial kit and previous total demineralization, to obtain STR profiles of old bone samples from three taphonomic processes (alkaline, acid and moist mitotic).

Materials and methods

29 skeletal remains from three different taphonomic contexts were processed: acidic, alkaline and wet-fungal. The amount of DNA obtained from three methodologies was evaluated in a comparative manner: organic extraction method (phenol-chloroform-isoamyl alcohol) (SO), extraction by silica column KIT QIAamp® DNA Investigator of QIAgen® (KC) and the methodology of extraction by previous total demineralization (DP). Finally, the obtaining of the STR profiles from the methodology of greater performance was tested.

Results

The following quantification values were obtained: i) alkaline medium: 0.068 ± 0.07 ng/μL (SO), 0.021 ± 0.01ng/μL (KC) y 0.073 ± 0.052 ng/μL (DP); ii) acidic medium: 0.098 ± 0.064 ng/μL (SO), 0.041 ± 0.029 ng/μL (KC) y 0.068 ± 0.042 ng/μL; iii) Wet-mitotic medium: 0.25 ± 0.061 ng/μL (SO), 0.04 ± 0.027 ng/μL (KC) y 0.15 ± 0.072 ng/μL (DP). Likewise, using the DNA samples obtained by the SO method, complete profiles were obtained for the wet taphonomic context while the alkaline taphonomic process proved to be the most drastic for DNA degradation, presenting a greater number of incomplete profiles.

Conclusions

The methodology of organic extraction was optimal in obtaining DNA from the three taphonomic processes evaluated. On the other hand, the wet-fungal taphonomic process is the one that produces the least negative impact on the preservation of DNA from skeletal remains.