Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Michael Bohnert is active.

Publication


Featured researches published by Michael Bohnert.


International Journal of Legal Medicine | 1999

A quantitative immunohistochemical study on the time-dependent course of acute inflammatory cellular response to human brain injury

R. Hausmann; A. Kaiser; C. Lang; Michael Bohnert; P. Betz

The time-dependent inflammatory cell reaction in human cortical contusions has been investigated during the first 30 weeks after blunt head injury. Immunohistochemical staining was carried out using CD 15 for granulocytes and LCA, CD 3 and UCHL-1 for mononuclear leucocytes. In order to provide reliable data for a forensic wound age estimation, the intensity of the cellular reaction was evaluated with a quantitative image analysis system. CD 15-labelled granulocytes were detectable earliest 10 min after brain injury, whereas significantly increased numbers of mononuclear leucocytes occurred in cortical contusions after a postinfliction interval of at least 1.1 days (LCA), 2 days (CD 3) or 3.7 days (UCHL-1), respectively.


International Journal of Legal Medicine | 2000

Spectrophotometric evaluation of the colour of intra- and subcutaneous bruises.

Michael Bohnert; R. Baumgartner; Stefan Pollak

Abstract Spectrophotometric measurements were performed on intra- and/or subcutaneous bruises occurring in direct temporal connection with peracute fatal trauma. The purpose of these measurements was to determine whether the visual colour impression of a fresh traumatic extravasation can give information on the localisation of the haemorrhage in a certain tissue layer. After visual assessment of the colour of the bruise, the spectral reflectance curves and the CIE-L*a*b* colour values were determined with the help of a diode array spectrophotometer. The localisation and size of the haemorrhages in the cutis and/or subcutis were evaluated morphologically after incision of the skin. It was confirmed that there is a relationship between the colour impression and the localisation of the bruise. Bruises localised near the surface have a more reddish appearance while bruises in deeper layers give a more bluish colour impression. An explanation may be found in the optical characteristics of skin. Blood localised in the subcutis appears blue on the surface due to scattering processes in the dermis (Rayleigh scattering), as the blue wavelengths of the light are scattered (and thus reflected) to a greater extent than the red wavelengths.


Forensic Science International | 2003

Complex suicides by self-incineration

Michael Bohnert; Markus A. Rothschild

Among the few cases of suicidal self-incineration primary or secondary complex suicides are a rarity. Accordingly the number of reports on this subject in the forensic literature is small. In a retrospective analysis of the Freiburg and Berlin autopsy material, four cases were found within an observation period of 11 years. These are described together with seven other cases reported in the literature. Altogether most of these suicides are primary combinations, especially with falls from a height. Other combinations include hanging or the infliction of stabs, cuts or gunshot injuries. The sex and age distribution is similar to that found for suicide by self-incineration alone.


International Journal of Legal Medicine | 2001

Post-mortem detection and identification of sildenafil (Viagra) and its metabolites by LC/MS and LC/MS/MS

Wolfgang Weinmann; Michael Bohnert; Alexander Wiedemann; M. Renz; N. Lehmann; Stefan Pollak

Abstract The highly putrefied corpse of an 80-year-old man was found in the apartment which he had rented to a prostitute. A package of Viagra 25 was found beside the corpse and three tablets were missing. Autopsy revealed severe coronary artery sclerosis as well as signs of previous myocardial infarctions. For the detection and identification of sildenafil and three metabolites in urine and tissue samples, solid-phase extraction, LC/MS and MS/MS methods were developed. Blood was not available for toxicological analysis due to the putrefaction. For method development, urine from a volunteer who had ingested 25 mg sildenafil was collected over 8 h, and three metabolites were identified by MS/MS. These metabolites were also found in the victim’s urine. These findings prove that sildenafil was taken some time prior to death, but the causality of sildenafil intake and fatal cardiac failure could not be proven, since no blood was available for analysis. However, the administration of sildenafil was contraindicated due to several previous myocardial infarctions.


Forensic Science International | 1997

Fractures of the base of the skull in charred bodies — post-mortem heat injuries or signs of mechanical traumatisation?

Michael Bohnert; Thomas Rost; M. Faller-Marquardt; Dirk Ropohl; Stefan Pollak

Based on a recent case, in which an expert opinion had to be prepared, the question was investigated if fractures of the base of the skull can result from the influence of heat on the human skull. Neither the retrospective analysis of autopsy records nor the prospective examination of charred bodies revealed any cases with heat-induced fractures of the base of the skull. Observation of cremations showed that the changes caused by the fire followed certain rules: fractures of the calvaria were seen after approximately 20 min; the base of the skull became exposed after about 45 to 60 min. In none of the 20 cremations watched could any fractures of the base of the skull be detected.


Forensic Science International | 2003

Problems associated with the diagnosis of vitality in burned bodies

Michael Bohnert; Christoph R. Werner; Stefan Pollak

The most important signs of vitality in burned bodies are soot deposits in the respiratory tract, the esophagus and the stomach as well as elevated CO-Hb values in the blood. But these findings show only that a person was exposed to fire fumes while alive; they are no indicator for vital heat exposure. As the external findings in burned bodies are often not very conclusive due to postmortem consumption by the fire, the internal findings are all the more important. Macroscopic signs that hot fumes were inhaled may be edematous swelling and vesicular detachment of the mucosa in the pharynx, the larynx and/or the upper section of the esophagus. As histological changes in the respiratory tract soot deposits, vesicular detachment of the epithelium, hyperemia and edema of the tracheal and bronchial mucosa as well as increased secretion of mucus have been described. These findings may partly be absent although the victim was alive during the fire, which can make diagnosis more difficult. Especially in peracute deaths vitality findings are usually sparse. The significance of the macroscopic and histological parameters of vitality was systematically investigated on the basis of our own autopsy material from the years 1996-2002 (88 cases) and compared with the statements found in the literature. In our study material, the vitality parameters were incomplete in 23% of the burned corpses. In 3% of the cases the question whether there was an antemortem heat exposure could not be answered.


Injury-international Journal of The Care of The Injured | 2002

A comprehensive classification of craniofacial fractures: postmortem and clinical studies with two- and three-dimensional computed tomography

Carlos H. Buitrago-Téllez; Wilfried Schilli; Michael Bohnert; Kurt W. Alt; Martin Kimmig

A comprehensive classification of midfacial/craniofacial fractures, based on two- and three-dimensional computed tomography (2D and 3D-CT) is presented. We performed a postmortem analysis of 24 patients who had died from trauma with signs of craniofacial fractures, based on 2D and 3D-CT studies with pathoanatomical findings. In addition, CT findings for 100 patients with craniofacial injuries requiring an emergency CT were correlated with surgical findings and follow-up results. On the basis of the analysis of a total of 377 fractures a classification system is proposed. The system is based on the use of the AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation) scheme, defining three types (A, B, C), three groups within each type (e.g. A1, A2, A3) and three subgroups within each group (e.g. A1.1, A1.2, A1.3) with increasing severity from A1.1 (lowest) to C3.3 (highest). The craniofacial region is divided into three units: the lower midface (I), the upper midface (II) and the craniobasal-facial unit (III). Lateral and central fractures are also distinguished. Type A fractures are non-displaced fractures, type B are displaced fractures and type C are complex/defect fractures. Groups A1, B1 and C1 comprise fractures of an isolated unit; groups A2, B2 and C2, combined fractures without involvement of the skull base; and groups A3, B3 and C3 are those combined fractures with involvement of the skull base. A correlation between the severity of the fracture and (i). the number of posttraumatic functional limitations (Spearman rank test, correlation coefficient r=0.42), (ii). the need for bone grafting or dural plastic (r=0.39) and (iii). facial asymmetry (r=0.37), was observed. The proposed classification system allows standardised documentation of midfacial and craniofacial fractures, including those not precisely defined by the Le Fort classification scheme.


Forensic Science International | 1998

Lethal monointoxication by overdosage of MDEA

Wolfgang Weinmann; Michael Bohnert

A 19-year-old man died after the intake of ten tablets of Ecstasy containing 3,4-methyl-enedioxy-N-ethylamphetamine (MDEA) as the main active ingredient. According to an eyewitness the symptoms of intoxication were strong sweating, sudden aggressiveness followed by hallucinations, subsequent failure of motoric coordination, severe spasms of arms and back, complete depression of the respiratory system, unconsciousness, and collapse. Resuscitation by an emergency doctor failed. Major autopsy findings were severe vascular congestion of all internal organs, liquid post-mortem blood, numerous subpleural and subepicardial petechial haemorrhages. By GC/MS analysis, MDEA was found in large amounts in serum (12 mg/l in femoral vein, 22 mg/l in heart blood serum), urine (201 mg/l), brain (18 to 28 mg/l) and in other tissue samples. Scalp-hair was highly positive for MDEA (17 ng/mg). Besides MDEA and its metabolites only trace amounts of MDMA could be found in urine and blood; no other drugs were detected. It can be concluded that the cause of death was a monointoxication by overdosage of MDEA.


Forensic Science International | 1999

Spectrophotometric evaluation of postmortem lividity

Michael Bohnert; Wolfgang Weinmann; Stefan Pollak

Under low ambient temperatures normally bluish postmortem lividity adopts a bright red or pink colour due to resaturation of haemoglobin with O2. The most important differential diagnosis in the presence of pink hypostasis is carbon monoxide poisoning. To answer the question if objective measuring methods allow differentiation of hypostasis with regard to cold exposition or carbon monoxide poisoning, spectrophotometric measurements were performed and the colorimetric measures as well as the spectral reflectance curves of the postmortem lividity were determined. The colorimetric measures CIE-L*a*b* showed similar values for all bright red livores mortis; differentiation between CO intoxication and cold exposition was not possible. Reflectance curves of pink hypostasis after cold storage showed the typical pattern of O2-rich blood with reflectance minima at wavelengths 541 nm and 576 nm and a reflectance maximum at 560 nm. Pink hypostasis because of carbon monoxide poisoning showed a shift of the reflectance maximum toward 555 nm and a flattened curve in all cases with COHb concentrations exceeding 52%, whereas these changes were not regularly observed with lower COHb levels.


International Journal of Legal Medicine | 2006

Expression of heat-shock protein 70 (Hsp70) in the respiratory tract and lungs of fire victims

S. Marschall; Markus A. Rothschild; Michael Bohnert

Immunohistochemical investigation of the respiratory tract and lungs of 63 fire victims revealed a statistically significant enhanced expression of heat-shock protein 70 (Hsp70) in the epiglottis, the trachea, and the main and the peripheral bronchi compared with a control group. In the fire victims, a strong expression of Hsp70 was discernible not only particularly in the vessels but also in seromucous secretory cells, ciliated epithelial cells, smooth muscle cells, and alveolar cells. The results suggest a vital or supravital reaction due to the inhalation of hot fire fumes.

Collaboration


Dive into the Michael Bohnert's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Dirk Ropohl

University of Freiburg

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Vera Sterzik

University of St. Gallen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Vera Sterzik

University of St. Gallen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge