Use of multiple pharmacodynamic measures to deconstruct the Nix-TB regimen in a short-course murine model of tuberculosis.

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen [bedaquiline-pretomanid-linezolid (BPaL)] during the first 3 weeks of treatment at human equivalent doses. The rRNA synthesis (RS) ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, together with solid culture CFU counts and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time-course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

Use of Multiple Pharmacodynamic Measures to Deconstruct the Nix-TB Regimen in a Short-Course Murine Model of Tuberculosis.

A major challenge for tuberculosis (TB) drug development is to prioritize promising combination regimens from a large and growing number of possibilities. This includes demonstrating individual drug contributions to the activity of higher-order combinations. A BALB/c mouse TB infection model was used to evaluate the contributions of each drug and pairwise combination in the clinically relevant Nix-TB regimen (bedaquiline-pretomanid-linezolid [BPaL]) during the first three weeks of treatment at human equivalent doses. RS ratio, an exploratory pharmacodynamic (PD) marker of ongoing Mycobacterium tuberculosis rRNA synthesis, to-gether with solid culture CFU and liquid culture time to positivity (TTP) were used as PD markers of treatment response in lung tissue; and their time course profiles were mathematically modeled using rate equations with pharmacologically interpretable parameters. Antimicrobial interactions were quantified using Bliss independence and Isserlis formulas. Subadditive (or antagonistic) and additive effects on bacillary load, assessed by CFU and TTP, were found for bedaquiline-pretomanid and linezolid-containing pairs, respectively. In contrast, subadditive and additive effects on rRNA synthesis were found for pretomanid-linezolid and bedaquiline-containing pairs, respectively. Additionally, accurate predictions of the response to BPaL for all three PD markers were made using only the single-drug and pairwise effects together with an assumption of negligible three-way drug interactions. The results represent an experimental and PD modeling approach aimed at reducing combinatorial complexity and improving the cost-effectiveness of in vivo systems for preclinical TB regimen development.

[On the quality of the external post-mortem examination in cases of fatal head trauma : A comparison of death certificate and forensic autopsy]. / Zur Qualität der ärztlichen Leichenschau bei todesursächlichem Schädel­Hirn­Trauma : Ein Vergleich von Todesbescheinigung und gerichtlicher Obduktion.

BACKGROUND: In Germany it is required by law that basically every type of physician needs to be capable of executing a correct external post-mortem examination of a corpse. In recent years, numerous investigations on external post-mortem examinations repeatedly reported systematic mistakes and erroneous procedures in various clinical and medicolegal case groups. Accordingly, the completion of death certificates is frequently performed incorrectly. As one of the typical unnatural death cases, decedents dying from fatal head trauma (FHT) represent a special autopsy case group, which is expected to be correctly recognized during the primary external post-mortem examination because the external injuries are mostly obvious. OBJECTIVE: The present study aimed at investigating the quality of the external post-mortem examination in medicolegal FHT cases by means of comparison of death certificates and autopsy reports from a 10-year period. MATERIAL AND METHODS: In a retrospective study design all autopsy cases from the Institute of Legal Medicine of the University Hospital Münster in the years 2006-2015 (n = 3611) were analyzed as to the presence of FHT. A total of 328 cases with FHT and the concomitant presence of a death certificate filled out before the autopsy were identified. Subsequently, the cause of death according to the death certificate was compared with the cause of death according to the autopsy. The degree of agreement was classified into six different categories from I to VI. While category I represented a complete lack of agreement, category VI was assigned to cases with full agreement. RESULTS: In 58.5% of the cases (category VI) FHT was identified correctly during the external post-mortem examination. In 1.5% of the cases, a completely different cause of death was determined during the external post-mortem examination (category I). In 19.2% of the cases, no cause of death or the statement "unclear" was given as the cause of death in the death certificate (categories II and III). Cross-analyses and intuitive heatmap visualization were generated to identify case constellations with an increased risk for discrepancies. These analyses revealed that among all discrepant cases (categories I-V), falls were found significantly more often than in the nondiscrepant cases (p < 0.01), especially falls of women older than 57 years (median age of women) or falls considered as accidents by the examiner. In addition, traffic-associated FHT of men older than 44.5 years (median age of men) was identified more frequently in the external post-mortem examination. CONCLUSION: Despite the fact that FHT should be a cause of death that is comparably easy to identify during external post-mortem examination, more than one third of the cases were not sufficiently recognized. Therefore, special attention must still be paid to certain case constellations during the external post-mortem examination. Typical examples of such cases are burned bodies, cases of advanced putrefaction and falls.

Understanding Subdural Collections in Pediatric Abusive Head Trauma.

Life-threatening physical abuse of infants and toddlers is frequently correlated with head injuries. A common variant of the abusive head trauma is the shaken baby syndrome. The present review article sheds light on subdural collections in children with abusive head trauma and aims at providing a recent knowledge base for various medical disciplines involved in diagnostic procedures and legal proceedings. To this end, the different subdural collection entities are presented and illustrated. The pathophysiologic background is explained. Differential and age-diagnostic aspects are discussed and summarized by tabular and graphic overviews. Two problematic constellations frequently occurring during initial CT investigations are evaluated: A mixed-density subdural collection does not prove repeated trauma, and hypodense subdural collections are not synonymous with chronicity. The neuroradiologic analysis and assessment of subdural collections may decisively contribute to answering differential diagnostic and forensic questions. In addition to more reference data, a harmonization of terminology and methodology is urgently needed, especially with respect to age-diagnostic aspects.

Subdural hygromas in abusive head trauma: pathogenesis, diagnosis, and forensic implications.

Are subdural hygromas the result of abusive head trauma? CT and MR imaging represent important tools for the diagnosis of abusive head trauma in living infants. In addition, in-depth understanding of the pathogenesis of subdural hygromas is increasingly required by neuroradiologists, pediatricians, and forensic physicians. Therefore, the current knowledge on subdural hygromas is summarized and forensic conclusions are drawn. The most important diagnostic pitfalls, benign enlargement of the subarachnoid space, and chronic subdural hematoma, are discussed in detail. Illustrative cases from forensic practice are presented. Literature analysis indicates that subdural hygromas can occur immediately or be delayed. If other infrequent reasons can be excluded, the presence of subdural hygromas strongly suggests a posttraumatic state and should prompt the physician to search for other signs of abuse. To differentiate subdural hygromas from other pathologies, additional MR imaging of the infant's head is indispensable after initial CT scan.

A glass fragment for a dagger--never mind your own hand.

A case of homicide is reported where a woman was killed by her boyfriend. He used a dagger-like fragment of a broken window glass to cause 10 atypical stab wounds to the neck and face and several incised wounds in other body regions. The cause of death was exsanguination, mainly from a severed internal jugular vein. The morphology of glass fragment injuries, both in the victim and perpetrator, is discussed and the possibility of homicide in such cases, which commonly represent accidents, is stressed. The use of an unsuited sharp force weapon carrying a high potential for self-injury can be explained by an excited state of mind.

Self-inflicted gunshot injury simulating a criminal offence.

An extraordinary case of a young woman with a gunshot wound to her left hand is presented. A typical near-contact entrance wound at the palm of the hand, extensive soft tissue destruction including nerve and vessel injury and a large stellate exit wound at the back of the hand were diagnosed and surgically treated. The woman initially stated that she had tried to repulse the pistol when a man shot her from close-range, which is consistent with the injury findings. After questioned thoroughly, however, she confessed self-infliction using a 8 mm blank pistol. This case demonstrates that a self-inflicted injury simulating a criminal offence can be present even if very atypical features such as the use of a firearm and mutilating or defence-like injuries clearly speak against it.

The morphology of cutaneous burn injuries and the type of heat application.

The morphology of burn injuries in 120 consecutive patients from the Department of Plastic and Reconstructive Surgery, CHR, Hospital B in Lille was correlated to the etiology and type of heat. Analysis identified five typical patterns of cutaneous burn injuries. Jet of flame-pattern from methylated spirits and gasoline detonations: superficial burn injuries; sparing of skin wrinkles and the submental region; absence or small amounts of soot; preference of exposed body regions, esp. the face and hands. Explosion-pattern from explosions and electrothermal injuries: superficial burn injuries; sparing of skin wrinkles but not of the submental region; soot; preference of exposed body regions. Alveolar soot arrangement and metallisation in electrothermal injuries. Considerable third-degree burns in dust explosions. Flame-pattern from direct flame effects due to burning gasoline or oil, open fires or ignited clothing: nonuniform depth including large third-degree burns; no sparing of the submental region; soot; preference of body regions covered by clothing. Immersion-pattern: superficial (bullous) injuries; blurred junction between scalded and unscalded areas; extremities, buttocks, and back are favourite sites; cave child abuse: waterlines and zebra-burns. Spilling-pattern: superficial injuries; sharp junction between scalded and unscalded areas; head, anterior trunk, and upper extremities are favourite sites; running off and splashing stains. Consideration of these patterns can assist the reconstruction in fire investigations or unclear scaldings. In cases of suspected arson, a typical burn injury pattern or a single finding not compatible with the rest of the pattern can disprove a suspect or raise the level of suspicion.

Bloodstain pattern analysis--casework experience.

The morphology of bloodstain distribution patterns at the crime scene carries vital information for a reconstruction of the events. Contrary to experimental work, case reports where the reconstruction has been verified have rarely been published. This is the reason why a series of four illustrative cases is presented where bloodstain pattern analysis at the crime scene made a reconstruction of the events possible and where this reconstruction was later verified by a confession of the offender. The cases include various types of bloodstains such as contact and smear stains, drop stains, arterial blood spatter and splash stains from both impact and cast-off pattern. Problems frequently encountered in practical casework are addressed, such as unfavourable environmental conditions or combinations of different bloodstain patterns. It is also demonstrated that the analysis of bloodstain morphology can support individualisation of stains by directing the selection of a limited number of stains from a complex pattern for DNA analysis. The complexity of real situations suggests a step-by-step approach starting with a comprehensive view of the overall picture. This is followed by a differentiation and analysis of single bloodstain patterns and a search for informative details. It is ideal when the expert inspecting the crime scene has also performed the autopsy, but he definitely must have detailed knowledge of the injuries of the deceased/injured and of the possible mechanisms of production.

Fatalities related to medical restraint devices-asphyxia is a common finding.

A total of seven detailed death investigations is reported where death occurred while being restrained by a belt or a protective cover. The casualties were elderly persons who mostly showed considerable pre-existing diseases, especially dementia and coronary atherosclerosis. Concerning the cause of death, three groups were differentiated: (I) mechanical asphyxia from strangulation. (II) Mechanical asphyxia from thoracic/abdominal compression. (III) Compression of thorax/abdomen without clear signs of asphyxia. Subgroups II and III each involved one case of rib fractures without preceding resuscitation. In subgroup III, the presence of considerable compression of the trunk and the absence of a natural cause of death strongly indicate a causal connection between compression and death, e.g. from a shortened course of fatal asphyxia, endocrine stress reactions or a head-down-position: cardiac arrest in a helpless situation. The method of restraint was inadequate in most cases in that only one device was used which did not restrict the capability to move sufficiently. A good clinical documentation including medical indication, duration and method of restraint and a description/photograph of the original on-site appearance is essential but was not present in most cases. Therefore, prophylaxis is based on a clear medical indication, the proper use of restraint devices, detailed instructions of the nursing personnel and close monitoring. The forensic investigation should aim at a complete reconstruction based on autopsy, histology, toxicology and inspection of the scene and the medical records.

Sudden death due to giant cell coronary arteritis.

An 89-year-old woman was found dead lying in her bed. Autopsy demonstrated a pronounced thickening of all coronary arteries except for the first 2-4 cm. Death was due to a recent myocardial infarction. Microscopically, the coronary arteries showed a substantial concentric thickening of all three layers with 90% narrowing. There was a dense transmural inflammatory infiltration with lymphocytes, macrophages, and numerous multinucleated giant cells. The CD68 positive giant cells were mostly located at the media-intima border in the vicinity of fragmented fibers of the lamina elastica interna. The aorta and its major branches including the carotid arteries, however, were free of inflammation and thickening. The findings were characteristic for giant cell arteritis, the equivalent of temporal Horton arteritis, but isolated involvement of the coronary arteries is exceptional.

High-throughput axial MALDI-TOF MS using a 2-kHz repetition rate laser.

A high-throughput axial MALDI-TOF mass spectrometer utilizing a laser with a 2-kHz pulse repetition-rate was constructed and tested. This fast mass spectrometer provided a data acquisition rate 10 times faster than a commercially available (200 Hz) axial mass spectrometer, while maintaining comparable limits of detection (200 amol of Glu fib peptide). Mass resolution, only slightly less than the commercial instrument (10 000 vs 14 000), was sufficient for baseline resolution of isotopic clusters of peptides with m/z <2700. A new method of mass calibration, which combined a limited number of internal and external standards, provided the same 15 ppm mass accuracy over the entire sample plate on either instrument. Implementing the 2-kHz laser required a faster data acquisition system and high-voltage pulse electronics, together with a novel strategy for rapid sample plate movements during acquisition, to achieve a sample analysis rate of up to 2 spots/s (with 800 shots/spot). The overall performance of the fast MALDI-TOF MS instrument was demonstrated by the acquisition, in 12 min, of an LC-MS data set from a plate of 625 fractions collected during LC separation of an 16O/18O differentially labeled proteomic sample of a tryptic digest of an E. coli lysate.

Two unusual stab injuries to the neck: homicide or self-infliction?

A 31-year-old woman was found dead by her daughter, lying in the living room which showed a large pool of blood, secondary droplets and stains from arterial blood spatter, dropping and contact. This bloody scene and two puncture wounds at the anterior aspect of the neck, one of them transecting the left common carotid artery leading to exsanguination, arose suspicion of homicide. However, the wound morphology including notches and a parallel skin incision as well as microradiography demonstrated that the two puncture wounds had been produced by glass. At the scene, a broken wine glass with two dagger-like tips had been standing on a table in front of a sofa where the woman had been sitting, and she most likely sustained the injury when she suddenly moved her head downwards, thus moving into the protruding tips. This self-inflicted accident demonstrates that inspection of the scene and synthesis of autopsy and scene findings can be crucial for a successful medico-legal reconstruction. The mechanism of producing the accidental injury is very extraordinary, in that the woman actively moved into a shattered wine glass instead of falling into an intact architectural glass surface.

Suffocation and poisoning--the hard-hitting side of Munchausen syndrome by proxy.

Munchausen syndrome by proxy (MSBP) is a severe and difficult to diagnose form of child abuse characterised by the simulation, aggravation or production of symptoms of illness in a child by an adult. MSBP often leads to multiple hospitalisations and has a high mortality and long-term morbidity. This study describes the cases of 5 families with 8 children affected who presented with unexplained neurological or gastrointestinal symptoms or even loss of consciousness. All were victims of poisoning or suffocation by their mothers. Two of those children died and were initially diagnosed as SIDS or natural death, respectively. They were only recognised as MSBP victims after another sibling had fallen ill with similar symptoms. The cases are discussed in consideration of the relevant literature. In addition warning signs of this forensically relevant syndrome and a strategy for the management of suspected MSBP cases are described.

Fatal hepatic haemorrhage in a child-peliosis hepatis versus maltreatment.

A 2.5-year-old boy with known myotubular myopathy (Spiro-Shy-Gonatas syndrome) and gonadorelin intake 9 months ante-mortem was found dead in his bed at home. At autopsy a ruptured subcapsular haematoma of the liver with resulting haemoperitoneum (600 ml) was found. Both lobes of the liver showed numerous circular blood foci <1 mm-2 cm in diameter. Signs of mechanical trauma such as bruising of the abdominal wall were absent. Histologically, the blood cysts were commonly connected to the sinusoids but did not have an endothelial lining and the reticular fibres showed ruptures. These pathomorphological findings are characteristic for peliosis hepatis and the cause of death was therefore determined to be exsanguination due to hepatic haemorrhage from peliosis hepatis instead of from mechanical trauma. To our knowledge this is the youngest casualty from peliosis reported so far.

Crossbow homicides.

A total of eight cases of homicide by crossbow are reported, including six intentional, assault-like killings and one hired killer. The bolts showed a high penetration capacity despite the rather low kinetic energy (<100 J): a field-tip traversed one upper arm and the thorax (36 cm) and two broadheads caused perforating injuries of the thorax (25-26 cm). This was due to the high sectional density and the split-like penetration mechanism. Wound morphology was especially important if the perpetrator had extracted the bolt, which occurred in half of the cases. The shape of the entrance wound depended on the type of arrowhead: broadheads produced star-shaped to triangular wounds, field-tips caused circular, oval or slit-like injuries. Foreign material from the arrowhead was found inside two injuries. In assaults, the crossbow was used to hunt the victim down from a short distance which does not require practice but still has the advantage of a distance weapon. However, immediate incapacitation occurred rarely so that additional violence was frequently applied. The noiseless character of the weapon explains why many victims were taken by surprise and why the corpses initially remained unnoticed. Crossbows can therefore be considered ideal weapons for man hunting and some were bought for the very purpose of the killing.

Analysis of 155 consecutive forensic exhumations with emphasis on undetected homicides.

A total of 155 consecutive forensic exhumations performed in Münster, Germany from 1967 to 2001 were evaluated retrospectively on the basis of the autopsy report, the police report and the death certificate. Histology and toxicology were performed in most cases. The postmortem intervals varied from 8 days to 8 years. Compared to other countries, the autopsy rate was low (1.2-1.4%) and the exhumation rate high (0.016%): principle of reciprocity. The cause of death could be clearly determined in 103 cases (66.5%) and histology or toxicology were decisive in 40%. Some findings were discernable using immunohistochemistry after considerable postmortem intervals, such as acute myocardial infarction after 1 year and pneumonia after 2 years and a diazepam intoxication was determined after 4.5 years. Major deviations between the cause of death as stated on the death certificate and as diagnosed after autopsy existed in 57 cases (37%). A more detailed analysis revealed five subgroups. 1. primary suspicion of intoxication (n=18) confirmed in 6 cases including 3 homicides (with parathion, clozapin, diazepam) which are described in more detail. 2. primary suspicion of homicide other than poisoning (n=51) confirmed in 19 cases. There was a serial killing of 15 patients by injection of air. In the remaining 4 cases, a shaken infant, craniocerebral injuries from blows with beer bottles, a craniocerebral gunshot and a multiplicity of blunt force injuries were diagnosed. The latter two cases are described in more detail. Superficial external examinations and the low autopsy rate were 2 common reasons for the occurrence of "buried homicides" (n=22)-not a single forensic autopsy had been performed directly after the death of the victims. 3. primary suspicion of medical malpractice (n=39). 4. accidents including traffic accidents (n=30). 5. clarification of the cause of death, circumstances or identity (n=17). Exhumations were frequently successful for recovering evidence which should better have been collected immediately after the death of an individual. Exhumations can also be regarded as an instrument to evaluate the quality of death certificates and death investigations.

Evaluation of the Reid index in infants and cases of SIDS.

The Reid index is an instrument for the evaluation of chronic bronchitis. The thickness of the mucosa and of its gland layer are measured and the relationship is expressed as a gland/wall ratio. Specimens were obtained from 124 autopsies from the German National Study on SIDS (GeSID). The cases were divided into three groups: group 1 typical SIDS ( n=47), group 2 SIDS with signs of mild inflammation of the respiratory tract ( n=50) and group 3 unnatural death controls ( n=23). The Reid index was measured in sections from the trachea, bifurcation/main bronchi and bronchioli (staining HE and PAS). The Reid index was remarkably constant throughout the different levels of the respiratory tract (standard deviation range 0.06-0.10). A comparison of the three groups did not show statistically significant differences. Group 1: mean Reid index trachea 0.37, bifurcation/main bronchi 0.38, bronchioli 0.39. Group 2: mean Reid index trachea 0.40, bifurcation/main bronchi 0.38, bronchioli 0.38. Group 3: mean Reid index trachea 0.39, bifurcation/main bronchi 0.38, bronchioli 0.41. It can be concluded that the dimensions of bronchial glands do not vary in cases of SIDS as compared to controls. This demonstrates that the Reid index has no significance in the vast majority of SIDS cases and that acute inflammation commonly does not produce an elevated Reid index. In addition, the Reid index was confirmed to be a valid instrument to study the respiratory tract including the trachea due to its stability and it was found that the Reid index is age-dependent: compared to adults, the ratios in infants were higher.

Fatal cerebro-renal oxalosis after appendectomy.

A case of a 24-year-old male with fatal cerebro-renal oxalosis assumed to be due to infusions of the sugar surrogate xylitol after appendectomy is reported. The diagnosis was established only after intensive histological investigations following the autopsy. The clinical picture was characterized by an acute seizure, coma and renal failure 2 days after the first xylitol infusion. Death occurred due to cerebral dysregulation as a very rare complication after parenteral administration of xylitol. Subendothelial double refractive calcium oxalate crystals were found in the walls of cerebral blood vessels, in particular in the stem ganglion regions and in the cortical renal tubules. The most common type of primary oxalosis was excluded by sequencing analysis. The young age, the minor surgical intervention and the otherwise unremarkable history are special features of this case. Since the genetic background of xylitol intolerance is still unclear, it is suggested that it should be banned as a sugar surrogate in clinical practice.