Virtopsy in der Unfallrekonstruktion

Mit der Virtopsy hat das Institut für Rechtmedizin der Universität Bern unter Prof. Dr. med. R. Dirnhofer und Prof. Dr. med. M. Thali die Rechtsmedizin über die ganze Welt revolutioniert. Obwohl einzelne Techniken, aus dem klinischen Medizinalltag stammend, bereits zu früherer Zeit im einen oder andere Autopsie-Saal bereits zur Anwendung kamen, waren es die Berner Rechtsmediziner, Radiologen und Ingenieure, welche diese kombinierten. Unter dem Begriff Virtopsy vereint sich die Nutzung von medizinischen bildgebenden Verfahren mit dem Erfassen der Körperoberfläche mittels 3D-Oberflächenscanning. Dadurch hat Virtopsy, nebst den rekonstruktiven Möglichkeiten, ein immenses Potential für die Dokumentation sowohl vom Verstorbenen als auch von Verletzungen von Lebenden. Gerade mittels der räumlichen Darstellung von inneren Verletzungen und Frakturen können diese für den medizinischen Laien optimal dargestellt und verständlich gemacht werden. Bei der Klärung von Verkehrsunfällen, insbesondere bei Kollisionen von Motorfahrzeugen mit Fussgängern oder Zweiradfahrern - gegenüber welchen der Mensch besonders exponiert und verletzlich ist - aber auch zur Klärung von Verletzungen an Fahrzeuginsassen, zeigen sich die rekonstruktiven Möglichkeiten von Virtopsy. Dabei gilt zu beachten, dass die 3D-Dokumentation mittels den erwähnten Verfahren eine Akquisition von digitalen Daten, nicht automatisch eine vollständige Auswertung zur Folge haben muss. Trotzdem zeigt sich, dass viele offene Fragen erst im Nachhinein auftreten, wenn die Befunde und Spuren nicht mehr zugänglich sind. Die mittels Virtopsy erhobenen digitalen Daten lassen sich jedoch zu jedem Zeitpunkt neu befunden oder weiter bearbeiten und können auch in Zukunft zur Klärung eines Unfallereignisses beitragen.

Wer lenkte den PW?

Die Rekonstruktion von Verkehrsunfällen ist ein interdisziplinäres Arbeitsgebiet. Verschiedene Institutionen wie z.B. die Polizei, die Rechtsmedizin oder die Unfallanalyse befassen sich mit der Beantwortung von juristischen Fragestellungen bei Verkehrsunfällen. Die modernen 3D-Dokumentations- und Analysemethoden und der Einsatz der bildgebenden Verfahren in der Rechtsmedizin ermöglichen eine disziplinübergreifende Auswertung der vorhandenen Spuren und Befunde und eröffnen damit ganz neue Horizonte und Dimensionen. Zudem ermöglichen sie es auch dem technischen Laien, eine bildliche Vorstellung der komplexen unfalldynamischen Abläufe zu geben. Im vorliegenden Beitrag wird anhand eines Falles die interdisziplinäre Fallanalyse und morphometrische 3D-Rekonstruktion vorgestellt und erläutert. Dieser Fall wurde Jahre nach dem Ereignis in Auftrag gegeben zur Klärung der Frage, wer den PW zum Unfallzeitpunkt gelenkt hatte. Die morphometrische 3D-Rekonstruktion umfasst die Ermittlung des Unfallhergangs, des biomechanischen Verhaltens der Fahrzeuginsassen und der Entstehung ihrer Verletzungen sowie der Entstehung der Blutspuren und weiterer Spuren und Beschädigungen im Fahrzeuginneren. Die Fahrzeuginsassen werden mittels Photogrammetrie und optischem 3D-Oberflächenscanning dreidimensional dokumentiert. Von verletzten Insassen werden zusätzlich die Daten klinischer radiologischer Untersuchungen von verstorbenen die vor der Obduktion durchgeführte Computertomographie (CT) und Magnetresonanztomographie (MRT) in die 3D-Analyse integriert. Das Fahrzeug und alle unfallrelevanten Objekte werden ebenfalls mittels Photogrammetrie und 3D-Oberflächenscanning erfasst. Ein 3D- Situationsplan der Örtlichkeit mit allen Spuren wird von der Polizei mittels Photogrammetrie und Laserscanning erstellt und in die Auswertung integriert. Anhand dieser 3D-Daten, insbesondere der Spuren am Unfallort und der Beschädigungen des Fahrzeuges, wird der Unfallablauf und daraus resultierend das biomechanische Verhalten der Fahrzeuginsassen rekonstruiert und in der Animationssoftware 3DS Max Design nachgestellt. Basierend auf den gewonnenen Erkenntnissen können morphometrische Vergleiche der Verletzungen mit den relevanten Strukturen im Fahrzeuginneren durchgeführt und so ermittelt werden, wie diese Verletzungen entstanden sind und auf welchen Sitzen die Insassen während des Unfalles sassen. Neben den Verletzungen können auch die Körpergrössen der Insassen Hinweise zur Ermittlung des Lenkers geben. Die Möglichkeiten der morphometrischen Rekonstruktion mittels der 3D-Techniken sind weitreichend und können oft entscheidende Erkenntnisse für das Ermittlungsverfahren liefern.

Twelve-month psychosis-predictive value of the ultra-high risk criteria in children and adolescents

Objective The validity of current ultra-high risk (UHR) criteria is under-examined in help-seeking minors, particularly, in children below the age of 12 years. Thus, the present study investigated predictors of one-year outcome in children and adolescents (CAD) with UHR status. Method Thirty-five children and adolescents (age 9–17 years) meeting UHR criteria according to the Structured Interview for Psychosis-Risk Syndromes were followed-up for 12 months. Regression analyses were employed to detect baseline predictors of conversion to psychosis and of outcome of non-converters (remission and persistence of UHR versus conversion). Results At one-year follow-up, 20% of patients had developed schizophrenia, 25.7% had remitted from their UHR status that, consequently, had persisted in 54.3%. No patient had fully remitted from mental disorders, even if UHR status was not maintained. Conversion was best predicted by any transient psychotic symptom and a disorganized communication score. No prediction model for outcome beyond conversion was identified. Conclusions Our findings provide the first evidence for the predictive utility of UHR criteria in CAD in terms of brief intermittent psychotic symptoms (BIPS) when accompanied by signs of cognitive impairment, i.e. disorganized communication. However, because attenuated psychotic symptoms (APS) related to thought content and perception were indicative of non-conversion at 1-year follow-up, their use in early detection of psychosis in CAD needs further study. Overall, the need for more in-depth studies into developmental peculiarities in the early detection and treatment of psychoses with an onset of illness in childhood and early adolescence was further highlighted.

Association of long-term nicotine abstinence with normal metabotropic glutamate receptor-5 binding

BACKGROUND Nicotine addiction is a major public health problem and is associated with primary glutamatergic dysfunction. We recently showed marked global reductions in metabotropic glutamate receptor type 5 (mGluR5) binding in smokers and recent ex-smokers (average abstinence duration of 25 weeks). The goal of this study was to examine the role of mGluR5 downregulation in nicotine addiction by investigating a group of long-term ex-smokers (abstinence >1.5 years), and to explore associations between mGluR5 binding and relapse in recent ex-smokers. METHODS Images of mGluR5 receptor binding were acquired in 14 long-term ex-smokers, using positron emission tomography with radiolabeled [11C]ABP688, which binds to an allosteric site with high specificity. RESULTS Long-term ex-smokers and individuals who had never smoked showed no differences in mGluR5 binding in any of the brain regions examined. Long-term ex-smokers showed significantly higher mGluR5 binding than recent ex-smokers, most prominently in the frontal cortex (42%) and thalamus (57%). CONCLUSIONS Our findings suggest that downregulation of mGluR5 is a pathogenetic mechanism underlying nicotine dependence and the high relapse rate in individuals previously exposed to nicotine. Therefore, mGluR5 receptor binding appears to be an effective biomarker in smoking and a promising target for the discovery of novel medication for nicotine dependence and other substance-related disorders.

High-resolution MALDI-FT-ICR MS imaging for the analysis of metabolites from formalin-fixed, paraffin-embedded clinical tissue samples.

We present the first analytical approach to demonstrate the in situ imaging of metabolites from formalin-fixed, paraffin-embedded (FFPE) human tissue samples. Using high-resolution matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry imaging (MALDI-FT-ICR MSI), we conducted a proof-of-principle experiment comparing metabolite measurements from FFPE and fresh frozen tissue sections, and found an overlap of 72% amongst 1700 m/z species. In particular, we observed conservation of biomedically relevant information at the metabolite level in FFPE tissues. In biomedical applications, we analysed tissues from 350 different cancer patients and were able to discriminate between normal and tumour tissues, and different tumours from the same organ, and found an independent prognostic factor for patient survival. This study demonstrates the ability to measure metabolites in FFPE tissues using MALDI-FT-ICR MSI, which can then be assigned to histology and clinical parameters. Our approach is a major technical, histochemical, and clinicopathological advance that highlights the potential for investigating diseases in archived FFPE tissues.

Bufferless Compression of Asynchronously Sampled ECG Signals in Cubic Hermitian Vector Space.

Asynchronous level crossing sampling analog-to-digital converters (ADCs) are known to be more energy efficient and produce fewer samples than their equidistantly sampling counterparts. However, as the required threshold voltage is lowered, the number of samples and, in turn, the data rate and the energy consumed by the overall system increases. In this paper, we present a cubic Hermitian vector-based technique for online compression of asynchronously sampled electrocardiogram signals. The proposed method is computationally efficient data compression. The algorithm has complexity O(n), thus well suited for asynchronous ADCs. Our algorithm requires no data buffering, maintaining the energy advantage of asynchronous ADCs. The proposed method of compression has a compression ratio of up to 90% with achievable percentage root-mean-square difference ratios as a low as 0.97. The algorithm preserves the superior feature-to-feature timing accuracy of asynchronously sampled signals. These advantages are achieved in a computationally efficient manner since algorithm boundary parameters for the signals are extracted a priori.

NO2-induced nitrate reductase activity in needles of Norway spruce (Picea abies) under laboratory and field conditions

The induction of activity of the enzyme nitrate reductase (NR, EC 1.6.6.1, 1.6.6.2) in needles of Norway spruce (Picea abies[L.] Karst.) by nitrogen dioxide (NO2) was studied under laboratory and field conditions. In fumigation chambers an increase in nitrate reductase activity (NRA) was detected 4 h after the start of the NO2 treatment. During the first 2 days with 100 µg NO2 m−3, NRA reached a constant level and did not change during the following 4 days. At the same level of NO2, NRA was lower in needles from trees grown on NPK-fertilized soil than on non-fertilized soil. After the transfer of spruce trees from fertilized soil to NPK-rich nutrient solution, NRA was transiently increased. This effect was assigned to root injuries causing nitrate transport to the shoot and subsequent induction of NRA. Neither trees on fertilized soil nor trees transferred to NPK-poor nutrient solution had increased NRA unless NO2 was provided. The NO2 gradient in the vicinity of a highway was used to test the long-term effect of elevated levels of NO2 on needle NRA of potted and field-grown spruce trees. Compared with less polluted sites, permanently increased NRAs were detected when NO2 concentrations were above 20 µg m−3. Controls of field measurements some 10 years after the introduction of catalytic converters in cars showed no significant change neither in NO2 levels nor in the decreasing NRA of spruce needles with the distance from the highway.

Characterization of the cholesterol 7$\alpha$-hydroxylase promoter in hypercholesterolemia -resistant rabbits

Our laboratory has developed and partially characterized a strain of New Zealand white rabbits that are resistant to the hypercholesterolemia which typically occurs in normal rabbits when fed a cholesterol-enriched diet. This phenotype is most likely attributed to an increase in bile acid excretion by hypercholesterolemia-resistant (CRT) rabbits as a result of elevated enzyme activity of cholesterol 7$\alpha$-hydroxylase (C7$\alpha$H), the rate-limiting enzyme in bile acid synthesis. Northern analysis revealed that CRT rabbits, in comparison to normal rabbits, have a 7-fold greater steady-state C7$\alpha$H mRNA levels irrespective of dietary regimen. The C7$\alpha$H gene in both phenotypes was determined to be a single copy gene. The hypothesis was that the elevated C7$\alpha$H mRNA levels in CRT rabbits, in comparison to normal animals, was due to an increase in the transcription rate of the C7$\alpha$H gene as a result of a mutation in a cis-acting element and/or a trans-acting factor within the hepatocyte. To isolate the C7$\alpha$H gene from both normal and CRT rabbits, genomic libraries were prepared from both phenotypes into $\lambda$GEM12 vectors using conventional techniques. Three CRT and one normal phage clones that contained the C7$\alpha$H gene were identified by screening the library with a series of probes located within different exons of the C7$\alpha$H cDNA. Sequencing analysis confirmed that approximately 1100 bp of the C7$\alpha$H 5'-flanking region from both normal and CRT phenotypes was identical. The increase in C7$\alpha$H mRNA levels was not attributed to a cis-acting mutation within this region. Liver nuclear extracts were prepared from normal and CRT rabbits maintained either on a basal or 0.25% cholesterol-enriched diet and incubated with several radiolabeled DNA fragments from the C7$\alpha$H gene. A 37 basepair region, located between nucleotides $-$452 to $-$416 was identified that had altered binding patterns between normal and CRT rabbits as a function of diet. Two additional regions, $-$747 to $-$575 and $-$580 to $-$442, produced banding patterns which were identical, irrespective of phenotype or diet. In conclusion, these studies suggested that the increase in C7$\alpha$H mRNA in CRT rabbits was due to differences in binding of a cholesterol-responsive transcription factor to the C7$\alpha$H promoter. ^

Colonización, Inmigración y Etnicidad en la Provincia de Misiones, Argentina. Etapa III Migraciones transnacionales y confluencias fronterizas e interétnicas en la provincia de Misiones-Argentina. 16H329

Actividades desarrolladas durante el período: Revisión bibliográfica; Investigación de archivos; Diseño del Trabajo de Campo. A partir de la primera puesta en práctica del Diseño, en los próximos años se volverá a revisar su pertinencia; Entrevista a informantes claves, observación participante; Sistematización, procesamiento y análisis de datos; Redacción de artículos y/o ponencias; Actividades académicas, difusión y transferencia.