Biomedical subjects

B Karger

Publications and source records attributed to B Karger.

At least 55 records · Page 3Linked to original sources

PubMed1998

Ketoacidosis and lactic acidosis--frequent causes of death in chronic alcoholics?

In clinical medicine, severe keto- or lactic acidosis associated with vomiting, nausea, abdominal pain, tachycardia or pathological respiration, has been described in chronic alcoholics. This study reports on fatalities of chronic alcoholics where the cause of death could not be determined by thorough autopsy, histology and toxicology including determination of alcohol concentration. In a first series, acetone was determined in the blood of such chronic alcoholics (n = 24), diabetics with metabolic decompensation (n = 7), cases of hypothermia (n = 7) and controls (n = 218). Among the 24 chronic alcoholics where the cause of death was unknown, 9 cases showed very high levels of acetone (74-400 mg/l). These comprised 6 cases without additional findings and 3 cases where a second patho-mechanism such as intoxication possibly contributed to the cause of death. In a second series, the sum values according to Traub (lactate/glucose) were determined in cerebrospinal liquor of chronic alcoholics with undetermined cause of death (n = 45), diabetics (n = 6) and controls (n = 39). Among the 45 alcoholics, 17 cases showed very high sum values (294-594 mg/dl) including 8 cases where non-lethal intoxications may have contributed to the final outcome. Other causes of a ketoacidosis or lactic acidosis (e.g. diabetes) were excluded in both groups of alcoholics. Consequently, ketoacidosis and lactic acidosis can be the cause of death of chronic alcoholics in a considerable number of cases where no pathomorphological or toxicological changes are present. A scheme for medical and laboratory examination is described.

Acetone↗

PubMed1998

Morphological findings in the brain after experimental gunshots using radiology, pathology and histology.

The tissue disruption inside the brain after experimental gunshots to the head was investigated with special reference to secondary bone missiles and intracranial pressure effects such as cortical contusion and deep intracerebral haemorrhages. The evidential value of various examination methods is compared. 9 mm Parabellum ammunition was fired to the temporal region of calves (n = 10) from a distance of 0-10 cm. Plain film radiography, CT, MRI, visual inspection and histology were performed on every brain. The tissue disruption of the permanent tract is delineated best by artefact-free MRI. Cortical contusions and deep intracerebral haemorrhages were detected infrequently by visual inspection and imaging techniques although they were present in every brain as verified by histology. These injuries remote from the tract increase cerebral wounding compared to non-confined tissue. In particular, the brain stem and central areas were frequent sites of haemorrhages, which can be expected to have serious and immediate consequences. Ectopic bone fragments were found in all brains using CT scans. Bone fragments were located inside clearly enlarged permanent tracts or were driven into brain tissue. In the latter cases, secondary shot channels up to 4 cm in length could be verified by histology. Cortical contusions and intracerebral haemorrhages can only be detected reliably by histology. The localization of bone fragments requires CT scans. Therefore, a detailed examination is accomplished best by a combination of the methods applied in this study.

Animals↗

PubMed1998

Attempted homicide by electrocution.

Attempted homicide by the application of a high-voltage, low-amperage current is reported in an elderly male. An electrician constructed an apparatus and applied the current to wet towels placed on the abdomen of the victim sleeping next door. The attempt was unsuccessful and resulted in burns only. The victim was hospitalised and died 3 weeks later. A causal connection could not be established between the attempted electrocution and the demise of the victim.

Aged↗

PubMed1998

Multiple entrance wounds from one bullet due to the use of a silencer.

When a bullet strikes an interposed object before entering a body, the bullet may fragment, or particles from the interposed object may be accelerated. Such secondary missiles may cause multiple entrance wounds if a body is located in line with their flight path. In the unusual case reported here, a silencer acted as an interposed object. The bullet disintegrated completely after impact with the central part of the silencer baffles, which were misaligned. Some bullet fragments were retained inside the silencer, and some exited as a collection of missiles, comparable to shotgun pellets. From a distance of several meters, the fragments wounded the victim at seven different anatomic sites. Use of a silencer should be considered when bullet fragments are recovered from a scene or victim but no other appropriate interposed object is found.

Firearms↗

PubMed1998

Experimental arrow wounds: ballistics and traumatology.

OBJECTIVE: To provide information on the ballistics and the wounding potential of different arrows or bolts fired from different weapons and to investigate the suitability of simulant media for experimental arrow wounds. METHODS: A longbow, a compound bow, and a crossbow were used to fire a variety of modern and ancient arrows. Fresh corpses of four adult pigs (47 shots) and blocks of gelatin and soap (48 shots) were used as target media, and the resulting wound tracts were examined. The range of fire was 8 m and the velocity was recorded at a distance of 3 m (and 16 m in additional shots) by light screen devices. RESULTS: The mean velocities recorded ranged from 45 m/s (longbow) to 67 m/s (compound bow). The excellent exterior ballistics of arrows results in only a small initial decrease in velocity of O.10 to 0.18 m x s(-1) x m(-1). The penetration depths were reproducible for the same arrowhead fired into the same simulant medium but differed considerably when compared with those in soft tissue. In nonbone tissue, the penetration depth was substantial (17-60 cm) and depended on velocity and especially on the type of arrowhead. All arrows penetrated deeply into the large body cavities and injured organs as long as no thick bone had to be perforated. Flat bones such as ribs were always perforated. Extraction of arrowheads from thick bone proved to be difficult in some cases. The wounding mechanism was a combination of incision and puncture, which facilitated deep penetration of tissue and produced clean-cut wounds. CONCLUSION: Gelatin and soap are not suitable for experimental arrow wounds. Every arrow wound carries a lethal potential. The severity of the wound depends primarily on the target area and the type of arrowhead. Extraction of arrowheads from thick bone has to be performed carefully.

Animals↗

PubMed1997

Backspatter from experimental close-range shots to the head. II. Microbackspatter and the morphology of bloodstains.

Backspatter is the ejection of biological material from a gunshot entrance wound against the line of fire. Backspatter of blood was investigated experimentally in transverse gunshots to the heads of calves (n = 9) from shooting distances of 0-10 cm. The resulting bloodstains were documented on white paper placed horizontally 60 cm below the impact site. The morphology of bloodstains and the distribution of microstains (diameter < 0.5 mm) is reported. The number of microbackspatter stains per gunshot varied between 39 and 262 and the maximum travelling distance was 69 cm while the vast majority of micro-droplets accumulated between 0 and 40 cm. The direction a single droplet can take comprises every possible angle between the most tangential ones to the skin surface. Microstains exclusively were circular to slightly oval. The morphology of macrobackspatter stains (diameter > 0.5 mm) varied from round to elongated with circular, drop-like and stains in the form of exclamation marks predominating. Small macrostains (0.5-4 mm) made up more than 90% of the macrostains and no systematic relationship between distance travelled and size of the stains could be established. The necessity of appropriate lighting and magnification in the investigation of surfaces for backspatter is stressed because many microstains are located in the proximity of the entrance wound where the firearm and the shooting hand are located in cases of close-range shots.

Blood Stains↗

PubMed1997

Who fired the gun? A casuistic contribution to the differentiation between self-inflicted and non-self-inflicted gunshot wounds.

A fatal gunshot wound to the thorax from a .357 Magnum revolver is reported. The entrance wound was located dorsally at the transition of the right shoulder and the upper arm, the exit wound below the left axilla and a re-entry at the medial aspect of the left upper arm. A friend of the victim, who was present when the gunshot was fired, stated that it was a self-inflicted accident. But the inclusion of both upper arms in the trajectory allowed a comparison between the posture of the upper arms at the moment the gunshot was fired and the posture of the upper arms necessary for a self-inflicted gunshot wound. This reconstruction, which is presented in detail, definitely excluded a self-inflicted wound. The friend then confessed that he had fired the gun accidentally.

Accidents↗

PubMed1997

Prior exposure of the entrance wound region from clothing is uncommon in firearm suicides.

According to an old rule still in use, gunshot suicides will rarely shoot through the clothing but will pull it aside to bare the skin. Thus, a bullet defect in the clothing would be an indicator for homicide or an accident. A total of 138 clearly defined gunshot suicides were analysed with regard to this topic. The thorax, which is commonly covered by textile, was the target for 27 suicides (19.5%). Of these 27 persons, 25 had fired through the clothing and 2 had placed the muzzle directly on the exposed skin, which represents a relative frequency of only 7%. Special features such as thick clothing or an affected state of mind did not appear to influence this behavior. Consequently, the perforation of textile does not suggest homicide or an accident - it is not applicable as a criterion for distinguishing different modes of death. Only in the rare cases when a gunshot victim is found with intact clothing covering the entrance wound can this finding be interpreted as an indication for suicide.

Clothing↗

PubMed1997

Laceration of the thoracic aorta from a .22 lr bullet.

A gunshot wound (.22 long rifle) to the chest including perforation of the aorta ascendens is presented. The small wound tract in soft tissue was characteristic for this type of ammunition and did not show any special peculiarities. However, arterial injury was not restricted to two small perforations, as expected in the light of previous wound ballistic findings. Three large longitudinal ruptures (3.0-4.5 cm in length and two of them independent of the perforations) additionally occurred, which led to rapid exsanguination. This extraordinary extent of vascular injury can be explained by perforation of the artery during the ventricular ejection phase, which causes a considerable dilation of the aorta analogous to a windkessel. The pre-existing dilation enables intraluminal temporary cavitation to have an "explosive" effect despite the high elastic tolerance to the vessel wall. The importance of tissue characteristics in gunshot wounds in general and the possible role of temporary cavitation inside the vessel in vascular gunshot wound production in particular are stressed.

Adult↗

PubMed1997

STR analysis on perforating FMJ bullets and a new VWA variant allele.

In three separate shooting incidents involving multiple gunshots, two FMJ bullets and one bullet fragment found at the scene (one from each case) were investigated for the presence of biological material from the victim after perforation. The surface of the missiles, which did not show obvious tissue traces when examined under a macroscope, was swabbed. PCR typing of up to five STR loci was performed on the small amounts of DNA extracted, which were seen below the detection limit of the slot blot quantification in one case. Nevertheless, individualisation of cellular material from the perforating projectiles was successful in each of the three cases presented. Consequently, identification of the victim wounded by a perforating bullet can reliably be achieved if contamination or removal of evidentiary material by improper handling is prevented. This technique is especially useful in cases where more than one person has fired a gun because the bullet carrying DNA can be linked to the firearm by investigation with a comparison microscope. As a by-product of this investigation, a variant allele 14 (14+4) at the VWA locus was detected.

Alleles↗

PubMed1997

Multiple gunshot suicides: potential for physical activity and medico-legal aspects.

Out of 138 clearly defined gunshot suicides which were autopsied, 11 persons (8%) fired two or more gunshots to the body. From these 11, 5 cases involved 2 gunshots to the head where the bullets fired first had missed the brain. The trajectories were restricted to the chest in three cases and a combination of gunshots to the head and chest including two perforating heart wounds without immediate incapacitation occurred in three more cases. Reliable incapacitation is based on physiological effects (tissue disruption) and can only be achieved by decreasing the functioning capability of the CNS. This can be accomplished by direct disruption of brain tissue or indirectly by cerebral hypoxemia from massive bleeding. Targets of immediate incapacitation are restricted to certain CNS areas and targets of rapid incapacitation include the heart, the (thoracic) aorta and the pulmonary artery. Other major blood vessels and major organs (lungs, kidneys, liver, spleen) constitute targets of delayed incapacitation. This general classification can be derived from the literature and is illustrated by the cases presented. A thorough post mortem can exclude or quantify the potential for physical activity. Typical features of single gunshot suicides such as contact shots, classical entrance wound sites and soot/backspatter on a hand also occur in multiple gunshot suicides.

Adult↗

PubMed1997

Unusual self-inflicted injuries simulating a criminal offence.

A total of 14 cases with self-inflicted injuries intended to simulate a criminal offence are reported. Typical characteristics of self-infliction such as superficiality, localisation at the anterior aspect, parallel course or avoidance of areas with high sensitivity to pain are substantiated by most of the cases analysed. However, the majority of cases also comprised atypical features including large hematomas of the extremities, a gaping cut wound, lip laceration, hematoma of the eyelids, concussion of the brain, large burn injuries and signs of bonding. Therefore, atypical injuries, which are either found in isolation or in combination with typical injury patterns, cannot exclude self-infliction. Initially, most "victims" did not intend to report the matter to the police but the persons whose affection was to be obtained made the report. Psychopathological motivations are predominant but rational motives such as attempted insurance fraud also occur.

Adolescent↗

PubMed1997

Pulmonary myelomonocyte subtypes in drowning and other causes of death.

Three immunohistochemically different myelomonocytic subtypes, i.e. MRP8, MRP14 and 27E10 were quantitatively evaluated in the intraalveolar, alveolar-interstitial and alveolar-intracapillary lung compartments. Lung sections from 5 major groups with defined causes of death, i.e. drowning and death during immersion (DI), cerebral/intracranial haemorrhages (CH), sudden cardiac deaths (SCD), hanging and throttling (HT) and immediate trauma deaths (ITD) were stained and the positive cells counted. The results show clear differences of the cell numbers on average. Among the different compartments the intracapillary cell count exhibits the highest numbers. If the cell counts are compared to the different causes of death, DI shows the highest values and ITD the lowest. The individual values, however, show considerable variations in all compartments and especially in the low cell count range. Within the DI group two subgroups can be differentiated, one having low and the other one having high cell numbers. This can be due to the type of agony, i.e. drowning versus immersion/hydrocution, or to resuscitation attempts or to a combination of both factors.

Adult↗

PubMed1997

Two cases of exenteration of the brain from Brenneke shotgun slugs.

A case of extended suicide resulted in two fatalities due to craniocerebral gunshots from a 12-gauge shotgun firing Brenneke shotgun slugs. In each case, the gunshot shattered the skull and the brain and in one case, large parts of the brain including a complete hemisphere were ejected similar to a "Krönlein shot". The location of the trajectory close to the base of the skull, the muzzle gases and the ballistic characteristics of the missile contributed to this rare form of head injury. The high mass and the large diameter of the lead missile do not necessitate a high muzzle velocity to crush large amounts of tissue or to produce an explosive type of head injury. The wadding material and the metal screw attached to the Brenneke slug can be of forensic significance.

Brain Injuries↗

PubMed1996

[Differentiation of hunting accident and suicide with rifles].

Criterias for the differentiation between hunting accidents and suicides are explained and discussed. A thorough investigation of this kind should always include autopsy, examination of the firearm, determination of the shooting distance and examination of the scene including an effort to reconstruct the events. Typical findings in suicides are contact shots, entrance wounds of the head, chest or upper abdomen, downward trajectories and evidence (gunshot residue, backspatter) suggesting a hand had been used to steady the muzzle. Typical findings in hunting accidents are entrance wounds of the extremities, the lower abdomen or the back, worn out or defective safety devices, upward trajectories and trajectories that are incompatible with possible and intended positions of the firearm. Each case has to be examined individually and the findings should be interpreted as an entity.

Accidents↗

PubMed1996

Backspatter from experimental close-range shots to the head. I. Macrobackspatter.

Backspatter is the ejection of biological material from a gunshot entrance wound against the line of fire. This phenomenon was investigated experimentally in transverse gunshots to the heads of calves (n = 9) using two types of 9 mm Parabellum ammunition from shooting distances of 0-10 cm. The resulting bloodstains were documented on white paper placed horizontally 60 cm below the impact site. In this report the analysis was restricted to stains with a diameter > 0.5 mm. Backspatter was documented after every gunshot. The number of stains varied from 31-324 per gunshot and appeared to be independent of the shooting distance. The maximum distance droplets travelled varied from 72-119 cm. The majority of droplets accumulated between 0 and 50 cm. The number of droplets and the distances travelled should be higher in man for anatomical reasons. The direction a single droplet can take comprises every possible angle between the most tangential ones to the skin surface. This resulted in a semi-circle of 180 degrees covered with stains. Skin ruptures of the entrance wound were not observed. The succession of events was documented on high speed film and started with the recoil of the firearm, immediately followed by a blow-out effect of the skin. Large droplets exited approximately 0.7-4 ms after the bullet impacted the skin. The calculated minimum initial velocity of these droplets was 13-61 m/s. Backspatter from gunshots to the head likely is caused by the hot gases expanding subcutaneously and by cavitation-related intracranial overpressure and tail splashing. In three out of nine gunshots, secondary backspatter additionally occurred as a result of droplets produced by a stream of blood from the entrance wound impacting the paper surface.

Animals↗

PubMed1996

On the physics of momentum in ballistics: can the human body be displaced or knocked down by a small arms projectile?

Shooting incidents are often portrayed as resulting in a sometimes violent backwards displacement of the victim. This opinion is also not infrequently held by expert witnesses. The physical force responsible for this would be momentum (mass x velocity). The physics of momentum in ballistic injury is explained in detail. The maximum momentum transferred from different small arms projectiles including large calibre rifles and a 12-gauge shotgun only results in a backwards motion of a 80 kg target body of 0.01-0.18 m/s, which is negligible compared to the velocity of a pedestrian (1-2 m/s). Furthermore, counterbalance is constantly maintained by neurophysiological reflexes. So the effect of the momentum transferred from the missile is virtually zero and there is no backwards motion of the person shot. Empirical evidence verifying these calculations can be obtained from hunting big game, from human gunshot victims and from a video documentary demonstrating the lack of any backwards motion of a person wearing body armour after hits from a centre fire rifle. So the alleged backwards hurling of a person shot is nothing but a myth which should be refuted not only because it is incorrect but also because it can result in miscarriages of justice.

Expert Testimony↗

PubMed1996

DNA typing of cellular material on perforating bullets.

DNA typing of cellular debris from perforating bullets was investigated following shooting experiments. A total of 14 perforating gunshots were fired into 9 calves. PCR typing of tissue fragments was done using bovine-specific primers flanking a 247 bp segment within the bovine lactoglobulin gene. Positive amplification results were obtained for all 9 hollow point (HP) and all 5 full metal jacket (FMJ) bullets. In contrast to HP bullets the smooth surfaces of the FMJ bullets did not have visible biological material, which resulted in weaker bands in the DNA analysis compared to HP bullets. Tissue seemed to accumulate at the base of the projectiles. Due to the lack of a suitable marker in bovines, only a species identification was carried out on the DNA from tissue on the bullets. The small amount of DNA extract (up to 5%) required for specification is promising for the successful application of a set of short tandem repeat (STR) systems for individualization in humans. By individualizing tissue on perforating bullets, the bullet and the victim it passed through can be linked. This can assist the investigation of gunshot deaths, especially when several persons are involved in a gun fight.

Animals↗