Identification of biological samples in a case of contamination of a cytological slide preparation

Here we report a case where a discrete section of the cytological slide preparation of a female individual was obviously contaminated with pleura liquid of a female tumor patient. Analysis of the cancerous pleura liquid and the healthy cells of the slide preparation showed different DNA profiles, indicating that the material originated from two different female individuals. The DNA profile of the cell mixture revealed a heterogenous pattern whereby the alleles could be assigned to the healthy and the tumor patient. Loss of heterozygosity (LOH) was observed in four of eight short tandem repeat systems for the pleura liquid and the cell mixture. Despite the low amount of DNA on the slide preparation and the occurrence of LOH, it was possible to clarify the case and to support the assumption that a drop of cancerous pleura liquid contaminated the cytological slide.     

Medical negligence in drug associated deaths

According to epidemiological studies adverse drug events are one of the most frequently encountered complications during medical treatment, a leading cause of hospitalisation and frequent cause of death. However, medical malpractice claims due to medication errors seem to be relatively rare. Based on a retrospective multicentre study on medical malpractice cases with lethal outcome (n = 4450), drug related cases (n = 575) were further evaluated. In 50% of cases a causal connection between drug therapy and death could be ruled out already after autopsy. In 232 cases a causal connection between drug therapy and death could be approved (drug allergies, relative overdose, wrong application, mix-up of drugs and sepsis after injection abscess). However, within the legal context only in 70 cases a medication error was approved which was in 42 cases causal for death, in 28 not. Administration of contraindicated drugs, incorrect application and relative overdose in renal insufficiency are the prevalent mistakes. Concerning the frequency of ADE in epidemiological studies medication errors are underreported in all data sources on medical malpractice; this seems to be due to the fact that even doctors and attending physicians rarely recognize an ADE; furthermore approving the connection between drug effect and death is extremely difficult for the expert witness.     

Comparison of the Plexor HY System, Quantifiler and Quantifiler Duo kits using the Roche LightCycler 480 System and the ABI 7900 real time PCR instrument

In this study, we used two real time PCR platforms (Roche LightCycler 480 System and the ABI 7900 real time PCR instrument) to compare three commercial kits for DNA quantification. Special emphasis was put on PCR efficiency, detection limit and detection range. Furthermore, we tested the influence of the calibrator DNA included in the different kits on the absolute values. 40 artificial stain samples as well as 40 reference saliva samples were tested and compared. Two main observations could be made: the kits had a strong influence on the amount of DNA determined (Quantifiler^® < Quantifiler Duo^® < Plexor^® kit) whereas the real time PCR platforms showed no significant influence on the outcome.     

Driving under the influence of amphetamine-like drugs

Scientific opinions differ whether the use of stimulants causes deterioration in driving skills. In 1857 of 8709 cases of driving under the influence of drugs, amphetamine-like drugs (amphetamine, methamphetamine, and methylendioxyamphetamine) were present either alone or together with other licit or illicit drugs. In 338 cases, amphetamines were the only psychoactive substance group in plasma at mean, median, and highest concentrations of 0.18, 0.12, and 1.05 mg/L, respectively. A widespread opinion is that after the consumption of amphetamines, centrally stimulating effects with corresponding consequences on safe driving are expected. In contrast, many cases were observed that rather suggested an influence of centrally sedating substances when considering the psycho-physical conditions. Relations between concentration and effect could not be established. The apparent sedation is probably the consequence of sleep deprivation during an amphetamine binge and the after-effects of the drug.     

Suicide by self-immolation

In the Western world, self-incineration is a rare event compared with the Asian countries. The circumstances of death are often unusual, and differentiation from homicide is sometimes possible only after evaluating all the investigation results and findings. In many cases of self-cremation, a fire accelerant is used. In our study material at least 30% of the body surface were burned. Unaffected skin was predominantly found on the back of the body. The cases presented by us are inhomogenous as to the motive and differ from those reported in the literature with regard to gender distribution, scene, motivational situation and psychological constitution.     

New trends in hair analysis and scientific demands on validation and technical notes

This review focuses on basic aspects of method development and validation of hair testing procedures. Quality assurance is a major issue in drug testing in hair resulting in new recommendations, validation procedures and inter-laboratory comparisons. Furthermore recent trends in research concerning hair analysis are discussed, namely mechanisms of drug incorporation and retention, novel analytical procedures (especially ones using liquid chromatography-mass spectrometry (LC-MS) and alternative sample preparation techniques like solid-phase microextraction (SPME)), the determination of THC-COOH in hair samples, hair testing in drug-facilitated crimes, enantioselective hair testing procedures and the importance of hair analysis in clinical trials. Hair testing in analytical toxicology is still an area in need of further research.     

Case histories in forensic medicine

Case histories make up a great part of publications in forensic medicine, especially forensic pathology, although considered low on the hierarchy of evidence based medicine because of its inherent anecdotal nature. Meanwhile some journals exclude case histories categorically from publication. The boom of case histories in forensic medicine has not only opportunity reasons (easily [even mental] and cheap to do) but also structural reasons: due to its tasks in case work many items of forensic medicine can not be simulated experimentally for ethical reasons (violent death, traumatic injuries, sexual assault, poisonings, influence of alcohol and drugs on driving ability and legal responsibility, medical malpractice, adverse events during medical care). In these fields the role of case histories is mainly the augmentation of experience based knowledge. However, quality aspects have to be considered and case histories should be the basis for systematic or hypothesis based research.