Forensic miRNA: potential biomarker for body fluids?

In forensic investigation, body fluids represent an important support to professionals when detected, collected and correctly identified. Through many years, various approaches were used, namely serology-based methodologies however, their lack of sensitivity and specificity became difficult to set aside. In order to sidetrack the problem, miRNA profiling surged with a real potential to be used to identify evidences like urine, blood, menstrual blood, saliva, semen and vaginal secretions. MiRNAs are small RNA structures with 20-25 nt whose proprieties makes them less prone to degradation processes when compared to mRNA which is extremely important once, in a crime scene, biological evidences might be exposed to several unfavorable environmental factors. Recently, published studies were able to identify some specific miRNAs, however their results were not always reproducible by others which can possibly be the reflection of different workflow strategies for their profiling studies. Given the current blast of interest in miRNAs, it is important to acknowledge potential limitations of miRNA profiling, yet, the lack of such studies are evident. This review pretends to gather all the information to date and assessed a multitude of factors that have a potential aptitude to discrediting miRNA profiling, such as: methodological approaches, environmental factors, physiological conditions, gender, pathologies and samples storage. It can be asserted that much has yet to be made, but we pretend to highlight a potential answer for the ultimate question: Can miRNA profiling be used as the forensic biomarker for body fluids identification?

Assessment of drug addiction. The experience of the Medico Legal Institute of Oporto.

Since 1993 in Portugal, it is possible, by legal enforcement, to request forensic examination to study possible conditions of drug addiction. On the basis of examinations carried out in the Medico Legal Institute of Oporto, we present a study of 494 cases involving the relation to the demographic data of the examined individuals, their family background, legal situation, age at which drug consumption began, consumption profile at the beginning and at time of forensic examination and our conclusions.

Child sexual abuse: a preliminary study.

In 1997, 52 child victims of sexual abuse were examined at Oporto Institute of Forensic Medicine. The authors analysed the data concerning these cases in an attempt to contribute to the elucidation of child sexual abuse, particularly in the north of Portugal.

Sexual abuse within the marital relationship.

The authors aim to characterise sexual abuse within the marital relationship. They analyzed the reports of the clinical examinations performed at the Institute of Legal Medicine of Oporto on victims of sexual abuse from January 1990 until December 1994. They also randomly interviewed victims of physical abuse at the Institute to determine if sexual abuse was performed by their partners. This study shows that complaints are rarely reported by victims of sexual abuse in marital relationships, and in all the cases studied where sexual abuse was verified it was accompanied by other forms of abuse.

Occupational handicap in victims of limb injuries.

The authors analysed 115 victims of limb injuries due to traffic accidents, to compare the medico-legal assessment by the rate of permanent disability (PD) with a tridimensional evaluation of the damage (lesion, function and situation), from a professional aspect. There was a high correlation between PD and lesional and functional sequelae. However, in professional situations only with those who were working full-time was there a high correlation with PD. PD gives only a lesional assessment. The authors propose a professional damage evaluation which considers the handicap of the individual in her/his ordinary work besides the lesion and function, as long as the assessment is personal and it is meant to reintegrate the victim completely in her/his professional life.

Detection of viable myocardium by dobutamine and dipyridamole stress echocardiography.

The basic aspect of cell behaviour that is the clue for viability recognition by stress echo is regional function. By definition, the function is depressed both in viable and in necrotic segments. However, only viable segments retain a contractile reserve; which can be evoked by an inotropic challenge, either cathecolaminic or flow-mediated, as consistently shown by several experimental studies. This is the basis of viability recognition by pharmacological stress echocardiography. Both dobutamine and dipyridamole exploit the same pathophysiological principle: viable tissue has a residual contractile reserve, which can be elicited by an appropriate inotropic stimulus. With dobutamine, the stimulus is a beta-receptor mediated effect on myocardial cell, which is later matched by an increase in flow. With dipyridamole, the primary stimulus is an adenosine A2-receptor mediated effect on the coronary arteriole smooth muscle cell, leading to an increase in flow. At that point, the increase in function is to be expected on the basis of the known relationship between myocardial contractility and coronary perfusion. From the technical point of view, the "viability window" is dose-related with dobutamine, and time-related with dipyridamole--where the same dose is associated to an early inotropic phase followed by a later ischemic response. In spite of the different pathophysiological background and technical modalities, dobutamine and and dipyridamole have shown a similar sensitivity and specificity for prediction of viability, with an overall accuracy only marginally lower than resting thallium. The practical, clinical impact of these observations is still blunted by relatively small numbers of observations in highly selected populations including a limited number of patients and studies in very few centers.(ABSTRACT TRUNCATED AT 250 WORDS)