Minimally invasive post-mortem CT-angiography in a case involving a gunshot wound

Non-contrast post-mortem computed tomography (pm-CT) is useful in the evaluation of bony pathologies, whereas minimally invasive pm-CT-angiography allows for the detection of subtle vascular lesions. We present a case of an accidentally self-inflicted fatal bullet wound to the chest where pm-CT-angiography revealed a small laceration of the anterior interventricular branch of the left coronary artery and a tiny disruption of the right ventricle with pericardial and pleural effusion. Subsequent autopsy confirmed our radiological findings. Post-mortem CT-angiography has a great potential for the detection of vascular lesions and can be considered equivalent to autopsy for selected cases in forensic medicine.

Civilian gunshot wounds to the genitourinary tract: incidence, anatomic distribution, associated injuries, and outcomes

Gunshot wounds (GSW) affecting the genitourinary (GU) system in civilians are uncommon. This study describes the incidence, anatomic distribution, demographics, associated injuries, management, and outcomes after civilian GU GSW.

A case of homicidal intraoral gunshot and review of the literature

Determination of the manner of death in case of intraoral firearm wounds can be a challenge, especially if the circumstances of the incident are unclear and crime scene investigation is inadequate. It is a well-known fact that the mouth is one of the selected sites for suicide with firearms. Homicidal shooting through the mouth is said to be rare, but does occur, and can be mistaken for a suicide. For discrimination between suicide and homicide in cases of intraoral firearm wounds, some useful points are the site of entry wound, the direction of the internal bullet path, the range of fire and the circumstances of death. We demonstrate these points in a case of a homicidal gunshot to the mouth assessed by both classical autopsy and post-mortem CT (PMCT).

Gunshot energy transfer profile in ballistic gelatine, determined with computed tomography using the total crack length method

By measuring the total crack lengths (TCL) along a gunshot wound channel simulated in ordnance gelatine, one can calculate the energy transferred by a projectile to the surrounding tissue along its course. Visual quantitative TCL analysis of cut slices in ordnance gelatine blocks is unreliable due to the poor visibility of cracks and the likely introduction of secondary cracks resulting from slicing. Furthermore, gelatine TCL patterns are difficult to preserve because of the deterioration of the internal structures of gelatine with age and the tendency of gelatine to decompose. By contrast, using computed tomography (CT) software for TCL analysis in gelatine, cracks on 1-cm thick slices can be easily detected, measured and preserved. In this, experiment CT TCL analyses were applied to gunshots fired into gelatine blocks by three different ammunition types (9-mm Luger full metal jacket, .44 Remington Magnum semi-jacketed hollow point and 7.62 × 51 RWS Cone-Point). The resulting TCL curves reflected the three projectiles' capacity to transfer energy to the surrounding tissue very accurately and showed clearly the typical energy transfer differences. We believe that CT is a useful tool in evaluating gunshot wound profiles using the TCL method and is indeed superior to conventional methods applying physical slicing of the gelatine.

Pistol thrown to the ground by shooter after fatal self inflicted gunshot wound to the chest

We report the case of a 46-year-old man found dead in his apartment in a chair with a gunshot wound in his chest. All circumstances pointed to suicide as the manner of death. Finding the weapon, a SIG Sauer P228 pistol, about 2 m away from the decedent with an obstacle between weapon and corpse however generated speculation about third party involvement. Scene investigations and ballistic calculations showed that with a high probability the weapon must have been purposefully thrown away by the decedent after he fired the lethal gunshot.

A residue close to ?1 loop F disrupts modulation of GABAA receptors by benzodiazepines while their binding is maintained

Benzodiazepines act at the major isoforms of GABA type A receptors where they potentiate the current evoked by the agonist GABA. The underlying mechanism of this potentiation is poorly understood, but hypothesized to be related to the mechanism that links agonist binding to channel opening in these ligand activated ion channels. The loop F of the ?(1) and the ?(2) subunit have been implicated in channel gating, and loop F of the ?(2) subunit in the modulation by benzodiazepines. We have identified the conservative point mutation Y168F located N-terminally of loop F in the ?(1) subunit that fails to affect agonist properties. Interestingly, it disrupts modulation by benzodiazepines, but leaves high affinity binding to the benzodiazepine binding site intact. Modulation by barbiturates and neurosteroids is also unaffected. Residue ?(1) Y168 is not located either near the binding pockets for GABA, or for benzodiazepines, or close to the loop F of the ?(2) subunit. Our results support the fact, that broader regions of ligand gated receptors are conformationally affected by the binding of benzodiazepines. We infer that also broader regions could contribute to signaling from GABA agonist binding to channel opening.

Importance of 3D-CT imaging in single-bullet cranioencephalic gunshot wounds

PURPOSE: The aim of this paper is to demonstrate that computed tomography (CT) and three-dimensional (3D) CT imaging techniques can be useful tools for evaluating gunshot wounds of the skull in forensic medicine. Three purposes can be achieved: (1) identifying and recognising the bullet entrance wound - and exit wound, if present; (2) recognising the bullet's intracranial course by studying damage to bone and brain tissue; (3) suggesting hypotheses as to the dynamics of the event. MATERIALS AND METHODS: Ten cadavers of people who died of a fatal head injury caused by a single gunshot were imaged with total-body CT prior to conventional autoptic examination. Three-dimensional-CT reconstructions were obtained with the volume-rendering technique, and data were analysed by two independent observers and compared with autopsy results. RESULTS: In our experience, CT analysis and volumetric reconstruction techniques allowed the identification of the bullet entrance and exit wounds and intracranial trajectory, as well as helping to formulate a hypothesis on the extracranial trajectory to corroborate circumstantial evidence. CONCLUSIONS: CT imaging techniques are excellent tools for addressing the most important questions of forensic medicine in the case of gunshot wounds of the skull, with results as good as (or sometimes better than) traditional autoptic methods.

Mutagenesis and computer modeling studies of a GPCR conserved residue W5.43(194) in ligand recognition and signal transduction for CB2 receptor

W5.43(194), a conserved tryptophan residue among G-protein coupled receptors (GPCRs) and cannabinoid receptors (CB), was examined in the present report for its significance in CB2 receptor ligand binding and adenylyl cyclase (AC) activity. Computer modeling postulates that this site in CB2 may be involved in the affinity of WIN55212-2 and SR144528 through aromatic contacts. In the present study, we reported that a CB2 receptor mutant, W5.43(194)Y, which had a tyrosine (Y) substitution for tryptophan (W), retained the binding affinity for CB agonist CP55940, but reduced binding affinity for CB2 agonist WIN55212-2 and inverse agonist SR144528 by 8-fold and 5-fold, respectively; the CB2 W5.43(194)F and W5.43(194)A mutations significantly affect the binding activities of CP55940, WIN55212-2 and SR144528. Furthermore, we found that agonist-mediated inhibition of the forskolin-induced cAMP production was dramatically diminished in the CB2 mutant W5.43(194)Y, whereas W5.43(194)F and W5.43(194)A mutants resulted in complete elimination of downstream signaling, suggesting that W5.43(194) was essential for the full activation of CB2. These results indicate that both aromatic interaction and hydrogen bonding are involved in ligand binding for the residue W5.43(194), and the mutations of this tryptophan site may affect the conformation of the ligand binding pocket and therefore control the active conformation of the wild type CB2 receptor. W5.43(194)Y/F/A mutations also displayed noticeable enhancement of the constitutive activation probably attributed to the receptor conformational changes resulted from the mutations.

Gunshot wounds to the acetabulum

To classify the fracture patterns of gunshot wounds to the acetabulum; identify the associated injuries and complications; determine the predictors of poor outcome and deep infection; and propose a treatment algorithm based on the results.

Evaluation of the chemical residue monitoring in animal-derived products in Switzerland

This paper evaluates whether the Swiss monitoring programme for foreign substances in animal products fulfils basic epidemiological quality requirements, and identifies possible sources of bias in the selection of samples. The sampling was analysed over a 4-year period (2002-05). The sampling frame in 37 participating abattoirs covered 51% of all slaughtered pigs, 73% of calves, 68% of beef and 36% of cows. The analysis revealed that some sub-populations as defined by the region of origin were statistically over-represented while others were under-represented. The programme that is in accordance with European Union requirements contained some relevant bias. Patterns of under-sampled regions characterized by management type differences were identified. This could lead to an underestimate of the number of contaminated animals within the programme. Although the current sampling was stratified and partially risk-based, its efficiency could be improved by adopting a more targeted approach.

Gunshot-related displacement of skin particles and bacteria from the exit region back into the bullet path

In previous studies, it was shown that there is a gunshot-related transport of skin particles and microorganisms from the entrance region into the depth of the bullet path. The present study deals with the question of whether gunshots may also cause a retrograde transport of skin particles and microorganisms from the bullet exit region back into the bullet path. For this purpose, we used a composite model consisting of rectangular gelatin blocks and pig skin. The skin pieces were firmly attached to the gelatin blocks on the side where the bullet was to exit. Prior to the test shots, the outer surface of the pig skin was contaminated with a thin layer of a defined bacterial suspension. After drying the skin, test shots were fired from a distance of 10 m using cartridges calibre .38 spec. with different bullet types. Subsequent analyses showed that in all shots with full penetration of the composite model, the bullet path contained displaced skin particles and microorganisms from the skin surface at the exit site. These could be regularly detected in the distal 6-8 cm of the track, occasionally up to a distance of 18 cm from the exit hole. The distribution of skin particles and microorganisms is presented and the possible mechanism of this retrograde transport is discussed.