One hundred and fifty-six teeth were extracted from corpses aged between 15 and 79 years. Of these, 101 teeth were selected for measurement of the mineral content of the root by photon beam absorption. Six or seven cross-sections were measured in each root, and the mean values calculated for the apical, medial, and coronal part within each decade. Further, 20 selected teeth were embedded in methacrylate and the length of the zone of transparency determined in longitudinal sections. There was no significant age dependency of the root's mineral content. There was no correlation between the extent of transparency and the mineral content.

Adolescent↗

PubMedDate not supplied

Report of a European collaborative exercise comparing DNA typing results using a single locus VNTR probe.

A collaborative exercise was carried out in 1989 among 12 European forensic laboratories using the single locus VNTR probe pYNH24, the restriction enzyme HinfI, the same set of human genomic DNA samples, and a standardized DNA size marker. The objectives of the exercise were: (1) to study the degree of variation within and between laboratories, (2) to obtain information on requirements for technical standardization allowing the exchange of typing results and (3) to compare different approaches for the identification of allelic DNA fragments of unknown size. Each laboratory carried out up to 10 independent typing experiments using the same DNA samples. The results were analysed independently by two laboratories using three different methods. The results of the exercise demonstrate the correlation of typing that can be achieved within and between laboratories under conditions of minimal standardization.

Alleles↗

PubMedDate not supplied

Polymorphism at the tetranucleotide repeat locus DYS389 in 10 populations reveals strong geographic clustering.

Several short tandem repeat polymorphism loci at the non-recombining part of the Y chromosome have been described recently and are now widely used for the investigation of the history and the diversity of man. The tetranucleotide repeat polymorphism at the DYS389 locus consists of two repetitive stretches with different numbers of (TCTG)n (TCTA)m repeat units. To study the overall variability of this locus, 768 alleles from males from 10 human populations (two sub-Saharan African, four Caucasoid and four Asian/Amerind populations) were investigated. The alleles found in the populations of different geographic origin exhibited remarkable differences in the number and arrangement of repeats in the two repetitive stretches and up to nine different sequence variants for a single fragment length have been detected. So far 53 different alleles, i.e. haplotypes, have been observed. Analysis of molecular variance (AMOVA) indicates that at least 24.5% of the total genetic variance was found between the populations and that these differences were significant in most pairwise comparisons. We propose a model, in which both founder effects and genetic drift together with single step replication slippage mutations explain the picture of haplotype diversity observed with this single locus.

Alleles↗

PubMedDate not supplied

LC-MS determination of oxydemeton-methyl and its main metabolite demeton-S-methylsulfon in biological specimens--application to a forensic case.

A sensitive method for the identification and quantitation of the organophosphate insecticide oxydemeton-methyl and its metabolite demeton-S-methylsulfon from human blood and various tissue samples has been established. After solid-phase extraction using C18 cartridges the extracts were analyzed by high-performance liquid chromatography with mass selective detection (Finnigan MAT LCQ). The method was completely validated. The limit of detection is 1 ng/g blood for the parent substance oxydemeton-methyl and 2 ng/g blood for the metabolite demeton-S-methylsulfon. This method was applied for the analysis of blood and tissue samples of a 58-year-old man who died after the intake of Metasystox R-Spezial, a product from Bayer containing oxydemeton-methyl. Because of a prolonged interval between the ingestion and death, the concentrations of oxydemeton-methyl and demeton-S-methylsulfon were very low. Although the body was already putrefied when the autopsy was performed, the chromatograms of blood and tissue samples were free of interfering peaks.

Autopsy↗

PubMedDate not supplied

[Forensic identification value of roentgen images in determining tooth-colored dental filling materials].

UNLABELLED: Identification of unknown bodies is mainly made by dental examination and comparison with accurate dental records. Therefore it is necessary to examine the jaws carefully and to locate every tooth-coloured dental restoration. Overlooking dental fillings can make positive identification impossible. The paper presented here evaluates the usefulness of radiographs to locate tooth coloured dental restorations. RESULTS: 40% of the dental materials tested here could not be detected radiographically with a sensitivity that is demanded. A radiographic examination is not sufficient and must be supplied by other techniques.

Acrylic Resins↗

PubMedDate not supplied

[Possibilities for using bedside cards as secondary comparison in trace element studies with the PCR technique].

When fresh blood is not available as a control in stain investigations extracted teeth, hair, preserved tissue samples, histological slides, cigarette butts or used stamps can also be used. This paper reports on a stain investigation performed 7 months after the death of the victim, where a bedside card from the medical records was successfully employed as a control blood sample. In a series of 10 bedside cards up to 9 years old, the investigation with the PCR method showed recognizable patterns in the STR systems SE 33 and TC 11. Matching patterns could be found from the 4 sections of each card (anti A, anti B, anti AB and anti D). A comparison of the oldest card with a fresh blood sample of the patient also showed matching patterns. AMPFLPs were successful with more recent cards. Using the PCR method typing of bedside cards from medical records up to 10 years old can be used in stain investigations.

Adult↗

PubMedDate not supplied

[Preservation of stab and cut wounds of the skin].

The authors compare different methods of fixation of stab and cut wounds of the skin. Fixation in formalin has more disadvantages than advantages despite its vast application. In our opinion fixation in formalin-free solution leads to better results especially with regard to subsequent investigations carried out later on. The best results were found with a modification of the Dietrich-Ratnewski fixing solution. This contains acetic acid, absolute alcohol, glycerin and water in the volume ratios 10: 15: 5: 70.

Fixatives↗

PubMedDate not supplied

[Unusual suicides with chain saws].

Two cases of suicide with bandsaws, undertaken by workers in carpenters' workshops are reported and discussed. Their choice of this method was based on the fact that they knew how dangerous such machines were. Both cases were watched by witnesses, who could not intervene due to the speed of the events. It was possible to exclude accident or homicide.

Adult↗