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The ability to perform successful DNA analysis on biological evidence obtained at a crime scene or during a sexual assault examination depends very much on the first step--how specimens are collected and preserved. Body fluids and their wet or dry stains, are often recovered using dry cotton swabs or cotton swabs moistened with sterile water or saline. In order to prevent decomposition and deterioration of a specimen, resulting in degradation or loss of DNA, it is recommended to either air dry or freeze these swabs as soon as possible after collection. We designed a simple, foldable cardboard box, which is suitable for the drying and storage of biological evidence collected on cotton swabs. Immediately after collection swabs are placed into the drying racks within the cardboard box, which is subsequently folded, labeled, sealed and initialed. At room temperature swabs completely air dry within the sealed box within 6-9 hours. In this box the evidence is properly packed, labelled and sealed, thus preventing cross contamination, degradation and sample switch. It is a valuable device for the collection of biological evidence at a crime scene, during sexual assault examinations, and for the collection of buccal swabs for PCR-based databasing and paternity testing.

Two vital tasks have to be taken into account in the examination of a victim and, if necessary, of one or more suspects also: Firstly, medical evidence must be reliably obtained, and secondly, the knowledge based on the findings obtained must, as soon as the victim has decided to notify the police, be interpreted in an expert form so that apart from explaining the criminal matters to an examining judge, i.e. a medical layman, it allows a legal assessment of the incident. Doctors in general practice and working in hospitals may occasionally be entrusted with the examination of sexual assault victims. As a rule, a forensic examination is only performed if a victim has notified the police and this examination and opinion are requested by the police or court. The most pressing medical task in such examinations is to confirm the assault and to undertake correct documentation and exhibition of biological traces. As has been shown by regular questioning of doctors, there is considerable uncertainty concerning the nature and method of correct documentation of the findings as well as the techniques for preparing exhibits. Each institute of forensic medicine in Switzerland maintains a flying service and keeps doctors available for advice round the clock; they can best be contacted through the emergency numbers of the local police forces.

This paper describes the first use of multiplex PCR amplification kits for the analysis of DNA extracted from cigarette butts in a criminal case. Two suspects could be excluded as potential contributors to the samples, whereas the multi locus PCR-based DNa profile derived from the cigarette butts was consistent with a DNA profile derived from a third suspect. For identity testing in criminal cases where cigarette butts are involved, commercially available PCR amplification kits provide currently the most powerful tool. Furthermore this PCR-based analysis can be implemented into most application orientated laboratories.

Genetic characterization of biological material in criminal cases and for parentage testing at the DNA level has gained wide acceptance. This paper describes the basic methodology of restriction fragment length polymorphism (RFLP) and the methodology based on the polymerase chain reaction (PCR). RFLP typing is performed in all cases where larger quantities of DNA are available because of its high discrimination power. PCR is used when only limited quantities of DNA or degraded DNA are available. There is a lot of applicabilities for the gynecologist, primarily in the investigation of sexual assault cases and in parentage testing of newborns, which is shown by several examples of forensic cases.

Nonoxinol 9 effectively inactivates high titres of HIV in vitro, which suggest its use for reducing HIV-transmission via sexual intercourse. Therefore, the suggestion has been made for the treatment of sexual assault victims with a topical anti-HIV agent such as nonoxinol 9 as soon as possible after a sexual assault has occurred. From the forensic point of view it becomes pertinent to determine whether or not nonoxinol 9 would have an adverse effect on the high-molecular weight deoxyribonucleic acid (DNA) in vaginal swabs and thereby impact RFLP results. The study demonstrates that nonoxinol 9 does not have a negative effect on the ability to produce RFLP patterns. Therefore, the early administration of the topical anti-HIV agent nonoxinol 9 has to be considered as an important step in the medical treatment of sexual assault victims.

For many years, the resolution of disputed paternity cases by genetic means relied on laboratory blood tests of red cell antigens and red cell and serum protein electrophoresis. These systems are generally characterized as lacking polymorphism and having low powers of exclusion, therefore it was necessary to use a panel of up to 23 marker systems. Over the past five years, a variety of DNA restriction fragment length polymorphism (RFLP) systems have been developed that characterize individuals at the DNA level. In this paper we describe the implementation of a Hae III RFLP system utilized in our laboratory for the resolution of disputed parentage cases as well as forensic casework. Since the analysis of highly polymorphic VNTR loci has proven to be the most powerful method to date for the determination of biological relatedness the utilization of the conventional methodologies should be completely replaced.

DNA from unrelated individuals (Caucasians; n = 200-271) from Switzerland were digested with Hae III and successively hybridized to the DNA probes D1S7, D2S44, D4S139, D10S28, D14S13, D17S26 and D17S79. An allele frequency distribution was determined for each locus. Furthermore, from the same individuals (n = 200) after amplification of DNA the allele and genotype frequencies at the HLA-DQ alpha locus were determined. The allele frequency distribution in Swiss Caucasians is statistically similar to American Caucasian population samples. In criminal cases a DNA-profile derived from four single-locus probes always leads to a very high value of discrimination and in paternity testing the probability of paternity always exceeds 99.9% regardless to the reference population used for biostatistical evaluation. Therefore for use in forensic analysis and paternity testing pooled caucasian databases might be used for the determination of the frequency of occurrence of a DNA-profile.

Benzodiazepine derivates can cause transient global amnesia even when administered in therapeutical doses. As amnesia seems to be more frequent than supposed, it is relevant for traffic medicine. We shall discuss forensic cases in which Midazolam amnesia was suspected with special attention to the interpretation of toxicological data.

The application of the rectal temperature time of death nomogram at the scene of death by 11 authors from 6 lego-medical institutes resulted in a standard deviation of the differences between nomographic and real death time of +/- 1.3 h in 46 cases (group I) with met requirements and clearly defined points of contact, nevertheless, including 9 cases with a more progressive cooling (0.5 greater than Q greater than or equal to 0.2). In cases with a real death time of more than 4h (N = 26) the standard deviation was +/- 1.0 hours corresponding to permissible variation of 95% of +/- 2.0 hours. Consequently, the permissible variation of 95% was much smaller than that suggested by the nomogram. The nomographic death time interval did not agree with the real one in 5 cases out of additional 30 cases with recognizably unsure points of contact (group II).

When tablet residues are found in the gastrointestinal tract during autopsy, this does not only indicate the possible presence of intoxication, but may also provide indications with the regard to the kind of intoxication (e.g. suicide) if the amount of tablets is considered. If tablets have already dissolved and thus large portions can no longer be detected with the naked eye, a definitive appraisal with regard to the presence of tablet residues is often difficult or even impossible on the autopsy table. A polarization microscopic screening method is described which enables identification of characteristic tablet auxiliary substances (maize starch, sodium carboxymethyl starch, microcristalline cellulose or sodium carboxymethyl cellulose) to be identified immediately and simply in the gastrointestinal contents. It also enables a rapid orientative screening for tablet residues in glasses found or the fluid these contained as well as in aspirated material and vomit. If the active agent of the tablet can be detected by chemical toxicology, the polarization microscopic diagnosis of abundant tablet auxiliary substances is compatible with intake of large amounts of drugs, which makes self-administration highly probable.

We report on an intraoperative lethal fat embolism and bone marrow embolism of the lung caused by implantation of hip endoprosthesis using acrylic bone cement. Autopsy revealed massive fat embolism of the lung and multiple bone marrow emboli within branches of the pulmonary arteries. It is concluded that there is a close relationship between implantation of hip endoprosthesis and death because fat embolism and bone marrow embolism was the only available evidence on post mortem examination.

We report a "crowsfoot-like" pattern in the smoke marks around the entrance of a close-range bullet wound in the center of the forehead; the weapon in this homicide was a revolver. This pattern only occurs if the facial muscles that form expression are completely contracted at the moment the shooting occurs and if the victim expects the event. The wrinkles gather around the entrance of the bullet, and this wound pattern may indicate that the shot was expected by the victim and represent a piece of the mosaic that might help clarify the circumstances in a case.

A 43 year-old female patient was admitted on account of severe dyspnoea of several months' duration and thrombocytopenia. The clinical symptomatology was compatible with pulmonary embolism, but no source of embolization was found and heparin therapy did not lead to clinical improvement. Angiography of the pulmonary artery revealed multiple filling defects. Symptoms improved after treatment with cortisone and so a malignant process was assumed. The patient died from right ventricular failure before the diagnosis could be established. At autopsy a sarcoma of the pulmonary artery, obviously originating from the pulmonary trunk was found. Thrombocytopenia most probably resulted from consumption of platelets by a mechanism corresponding to the Kasabach-Merritt syndrome. The difficulties in the diagnosis of pulmonary artery sarcomas are discussed and the 69 previously published cases are reviewed.

The case is reported of a 26 year-old man with a colloid cyst of the third ventricle (paraphyseal cyst; neuroepithelial cyst), which gave rise to a fatal increase in intracranial pressure. Despite repeated hospitalisation the diagnosis was not established prior to death. This report serves as a reminder that this rare disorder must be considered in the differential diagnosis of conditions causing increased intracranial pressure in view of the life-saving therapeutic management required to avert a fatal outcome.

Mustard gas or Yperite, an old and formerly well known chemical warfare agent was recently used against human beings in the Middle east. Some of the victims were transferred to European University Hospitals for intensive treatment. They all showed vesication of the skin and also the typical symptoms of severe damage of the respiratory mucosa. The macroscopical and microscopical observations after war gas exposure and the detection of mustard gas in biological material are reported.

Development, rearrangement and reaction to pressure on post-mortem lividity were investigated by using different shackle-instruments. The behaviour of post-mortem lividity at the shackle-point and its surrounding areas in some cases may allow to draw a conclusion, if shackle occurred during life or after death.

The autopsy of a newborn child that was found wrapped up in a plastic bag revealed a biparietal fracture of the skull. Only after knowing all circumstances it was possible to explain the origin of this fracture. A plausible reconstruction was possible after the inspection of the scene, the autopsy and by taking into consideration the statement of the mother. Thus it is could be decided that the death of the newborn child occurred by an accident while an infanticide, birth injury or labor precipitate causing the fracture was excluded.