[Contribution of the TUNEL method for post-mortem interval estimation: an experimental study]. / Apport de la méthode TUNEL dans l'estimation du délai post-mortem : une étude expérimentale.

The assessment of post-mortem interval is of major importance in forensic pathology. Many methods have been used in the early post-mortem period but remain rough. To test the hypothesis of an increased rate of apoptosis increasing with post-mortem interval, TUNEL method was applied in rats to study the relationship between the number of apoptotic cells in skin samples and the post-mortem interval. Our study showed that the post-mortem processes were associated with apoptosis in skin cells. The apoptosis rate was statistically correlated with post-mortem interval in the early post-mortem (less than 48 hours after death). The application of the TUNEL method for estimating the post-mortem interval in forensic pathology is discussed.

[A potential contribution of virtual slides and automatic image processing to the estimation of the vascularization of cranial sutures]. / Apport potentiel des lames virtuelles et de l'analyse d'images automatique dans l'estimation de la vascularisation des sutures crâniennes.

AIM: Determining age at the time of death is a difficult problem in forensic practice. The study of the vascularization of cranial sutures is an original approach, which may mark the process of synostosis associated with aging. Counting sections of blood vessels on a histological section of cranial suture, raises however a number of practical problems related to the quality of the preparation and to the method of quantification. The purpose of this study is to illustrate the potential contribution of an automatic analysis of virtual slides to overcome these problems. MATERIALS AND METHODS: The proposed method of analysis is illustrated from three samples of frontosphenoidal suture whose vessels were immunostained after decalcification of bone tissue. A high resolution image (x 20 objective and microscopic resolution of 0.5 microm) of each microscopic preparation was acquired through a microscopic scanning device. The automatic image analysis protocol takes advantage of a processing of virtual slides at two resolutions. RESULTS: The chosen strategy ensures the identification of the specific area of interest, the enumeration of blood vessel sections on the whole preparation and the visual control of the detected structures. CONCLUSION: The quantitative estimate of the vascularization of a large structure, such as a cranial suture, can benefit from scanning and fully automatic processing of virtual slides. The automatic analysis requires however an optimal preparation of tissues; decalcification and immunohistochemical staining must be done with great care.

A case in south-eastern France: a review of drug facilitated sexual assault in European and English-speaking countries.

Drug facilitated sexual assaults (DFSA) have been increasingly reported in the medical literature since the 1980s but their legal recognition is more recent, at least in Europe. From a case treated in south-eastern France, whose judicial consequences were known, it seemed of interest to carry out an international study of jurisprudence concerning this type of rape. While from the medical viewpoint the drugs used are well-known and their presence can be clinically verified, the legal consequences of their use in subsequent criminal prosecution is less clear-cut. Some European countries have no jurisprudence in this area, while others consider the use of drugs as an aggravating circumstance. In France, it was only in 2003 that the first case of DFSA was truly punished by the judicial system, with considerable media attention. By contrast, in English-speaking countries, particularly the United States, the use of drugs to facilitate sexual assault has frequently been recognized in legislation and in criminal prosecutions. Prevention is fundamental and is recognised as demonstrated by campaigns in various countries.

Apoptosis of neurons in cardiovascular autonomic centres triggered by inducible nitric oxide synthase after death from septic shock.

BACKGROUND: Results of experimental and clinical studies have shown that septic shock is associated with cardiovascular autonomic failure. Thus, we aimed to investigate the existence of ischaemia and apoptosis within the cerebral autonomic centres that control the cardiovascular system in patients with septic shock. METHODS: In a prospective cohort study, we did post-mortem examinations of supraoptic and paraventricular nuclei, cerebral amygdala, locus coeruleus, and medullary autonomic nuclei in 19 patients with septic shock, seven with non-septic shock and five who died suddenly from extracranial injury. Ischaemic and apoptotic neurons and microglial cells, and expression of tumour necrosis factor alpha (TNFalpha) and inducible nitric oxide synthase (iNOS) were scored. FINDINGS: Ischaemic, neuronal, and microglial apoptosis scores differed between groups (p=0.0007, p<0.0001, and p=0.0037, respectively) and were higher in patients with septic shock than in those with non-septic shock (p=0.0033, p=0.0005, and p=0.0235, respectively), and extra-cranial injury related deaths (p=0.0027, p=0.0007, and p=0.0045, respectively). There was little microglial activation and glial expression of TNFalpha. The scores for endothelial iNOS expression were different between the three groups (p<0.0001), and were higher in septic shock than in non-septic shock (p=0.0009) and than in extracranial injury related deaths (p=0.0007). Vascular expression of iNOS also correlated (Spearman tau=0.57) with autonomic-centre neuronal apoptosis in the combined septic and non-septic shock group. INTERPRETATION: Septic shock is associated with neuronal and glial apoptosis within the autonomic centres, which is strongly associated with endothelial iNOS expression.

Concentrated bleach burns in a child.

After a review of the literature on inflicted burns in children, we present a case of caustic burns in a child aged 6 months. Its interest lies in the causative agent (concentrated bleach) and in discussion of the intentional nature of the burn.

p16INK4a and its regulator miR-24 link senescence and chondrocyte terminal differentiation-associated matrix remodeling in osteoarthritis.

INTRODUCTION: Recent evidence suggests that tissue accumulation of senescent p16INK4a-positive cells during the life span would be deleterious for tissue functions and could be the consequence of inherent age-associated disorders. Osteoarthritis (OA) is characterized by the accumulation of chondrocytes expressing p16INK4a and markers of the senescence-associated secretory phenotype (SASP), including the matrix remodeling metalloproteases MMP1/MMP13 and pro-inflammatory cytokines interleukin-8 (IL-8) and IL-6. Here, we evaluated the role of p16INK4a in the OA-induced SASP and its regulation by microRNAs (miRs). METHODS: We used IL-1-beta-treated primary OA chondrocytes cultured in three-dimensional setting or mesenchymal stem cells differentiated into chondrocyte to follow p16INK4a expression. By transient transfection experiments and the use of knockout mice, we validate p16INK4a function in chondrocytes and its regulation by one miR identified by means of a genome-wide miR-array analysis. RESULTS: p16INK4a is induced upon IL-1-beta treatment and also during in vitro chondrogenesis. In the mouse model, Ink4a locus favors in vivo the proportion of terminally differentiated chondrocytes. When overexpressed in chondrocytes, p16INK4a is sufficient to induce the production of the two matrix remodeling enzymes, MMP1 and MMP13, thus linking senescence with OA pathogenesis and bone development. We identified miR-24 as a negative regulator of p16INK4a. Accordingly, p16INK4a expression increased while miR-24 level was repressed upon IL-1-beta addition, in OA cartilage and during in vitro terminal chondrogenesis. CONCLUSIONS: We disclosed herein a new role of the senescence marker p16INK4a and its regulation by miR-24 during OA and terminal chondrogenesis.

Value of histological study in the fronto-sphenoidal suture for the age estimation at the time of death.

The macroscopic study of cranial sutures is one of the methods that may be used in forensic anthropology to estimate age at the time of death. The present study aims at assessing the value of a microscopic analysis of the fronto-sphenoidal suture (FSS) sampled at autopsy, to determine both the physiological mechanisms responsible for the FFS closing during ageing and its value in the estimation of age at the time of death. We assessed the vascular capital as well as the apoptosis of conjunctive cells intervening as parameters in the physiological mechanism involved in cell ageing, in a population of individuals, whose gender and age was known. The FSS analysis was performed after decalcification and standard histological study, respectively with immunohistochemistry (Factor Von Willebrand antibody) VWF and (TdT-mediated dUTP nick end labelling) TUNEL method and caspase-3 immunohistochemical expression. In this study we found a significant reversed correlation between the degree of vascular expression of VWF and age at the time of death. There was also a significant positive correlation between the degree of apoptosis in the conjunctive cells of the FSS and age at the time of death. According to these results, suture closing during ageing can be explained by these two combined mechanisms of conjunctival apoptosis and vascular involution. Thus, the findings justify the study of closing sutures to estimate age at the time of death. Besides, it also enabled us to establish linear regressions. The vascular expression of the VWF enables to estimate an individual's age at the time of his death more or less at about 1.55 years, offering an interesting perspective both in forensic pathology and anthropology.

Age-at-death estimation based on the study of frontosphenoidal sutures.

Determination of age at the time of death based on the observation of cranial sutures has led to numerous studies with sometimes contradictory results. The initial hypothesis being that suture closure is part of an age-related physiological process, the conflicting results have been interpreted by various authors as secondary to the choice of sutures, under the co-existing influence of pathological factors or genetic factors, or even independent of age. Despite these differences, macroscopic methods remain much used in anthropology and in forensic medicine. In our work, we evaluated the value of the degree of closure of the frontosphenoidal suture in estimating age at death of mature subjects, with the secondary objective of establishing a linear regression which could be used in routine practice. The study concerned bone specimens from individuals whose age, sex and medical history were known. Macroscopic observation was carried out on the ectocranial and endocranial sides according to four stages of closure previously defined. 290 sutures were taken from a population of whom two-thirds were men. The method can be repeated and reproduced and the regression established shows the confidence range for average error to be +/-1.5 years. While this result is of interest in terms of precision in prediction for a group of people, the prediction range is too great (+/-23 years) to be applicable to a single individual as part of a forensic procedure.

Improvement in proximal aortic endograft fixation: an experimental study using different stent-grafts in human cadaveric aortas.

PURPOSE: To compare the proximal fixation characteristics of different types of stent-grafts (SG) and the adjunctive effect of a proximally placed Palmaz stent. METHODS: Human cadaveric aortas were obtained at autopsy and cut into 30 aortic segments. Appropriately oversized (10% to 20%) commercial stent-grafts (Zenith, Ancure, Excluder, Talent) and 4 configurations of homemade Palmaz-based stent-grafts (polytetrafluoroethylene or polyester coverings each with no uncovered proximal edge or a 20-mm bare section of stent) were implanted 20 mm into an aortic segment and balloon dilated. Each segment was placed in an experimental apparatus to measure the dislodgment force. Bare Palmaz stents were used to reinforce the proximal fixation of the commercial stent-grafts, and the measurements were repeated. Manual anastomoses were made and their dislodgment force tested for comparison. RESULTS: The median dislodgment force ranged from 6.5 N for the Excluder to 26.5 N for the Zenith (8.0 N for the Talent, 11.8 N for the Ancure, and 8.1 to 10.7 N for the various Palmaz stent-graft designs). There was no significant difference between the Zenith and the Ancure groups or between the Excluder and the Talent groups. However, the Zenith and Ancure devices required significantly higher (p=0.0004) force (approximately 25%) to displace them than the other stent-grafts tested. With the Palmaz stent added to the proximal attachment site, the median dislodgment force for the different commercial endografts was significantly improved for all devices (p<0.03): 34% for the Zenith device, 69% for the Ancure, 73% for the Talent, and 80% for the Excluder endoprosthesis. CONCLUSIONS: The Zenith stent-graft had the best resistance to dislodgment. An additional Palmaz stent placed at the proximal attachment site greatly improves endograft fixation regardless of the type of stent-graft. For complex aneurysm necks or for intraoperative type I endoleak management, an adjunctive Palmaz stent could be used.