Quantification of secondary dentine formation from orthopantomograms--a contribution to forensic age estimation methods in adults

The accuracy of most age determination methods in adults is unsatisfactory and therefore more precise methods are required. Teeth provide several useful points about an individuals age. With advancing age secondary dentine is deposited along the wall of the dental pulp chamber leading to a reduction in the size of the pulp cavity. These age-related changes can be determined and measured from dental radiographs. The aim of this study was to explore if measurements of the size of the pulp cavity performed on orthopantomograms can be used for individual age estimation. Measurements were made digitally for 6 types of teeth from orthopantomograms of 168 individuals aged between 14 and 81 years old. To compensate for errors due to the technique of radiography-for instance differences in angulation-ratios of distances were calculated: pulp/root length, pulp/tooth length and pulp/root width at three different root levels. The width ratios of the pulp cavity showed significant correlation to the chronological age and the coefficient of determination (r(2)) was highest in the upper lateral incisors (r(2)=0.913) when an exponential or a logistic regression model was constructed. At the same distance with a linear regression model the coefficient of determination (r(2)) reached 0.839.

A comparative study on the immunohistochemical detection of early myocardial damage

The study was undertaken to evaluate the kinetics and distribution patterns of several immunohistochemical markers in ischemically and hypoxically damaged myocardium. The myocardium of 8 cases of acute myocardial infarction (AMI), 8 cases of diagnosed acute cardiac death (ACD) and 12 cases of acute exogenic hypoxia (AEH) due to CO poisoning or hanging were analysed for depletion of the cardiac antigens FABP, troponin C and T, desmin and myoglobin, loss of CD59 and deposition of the plasma antigens fibrinogen, fibronectin and the terminal complement complex C5b-9. The visualisation of the terminal complement complex was positive as early as 30 min after onset of symptoms of AMI. Depletion of cellular antigens started earlier than the deposition of plasma antigens. The deposition of fibronectin and fibrinogen began earlier than the detection of C5b-9 but later than the depletion of the cellular antigens. Our findings indicate that for the immunohistochemical detection of very early myocardial damage, the depletion of myoglobin is at least of the same rank or better than depletion of FABP and troponin.

Expanding the forensic German mitochondrial DNA control region database: genetic diversity as a function of sample size and microgeography

Mitochondrial DNA control region sequences were determined in 109 unrelated German Caucasoid individuals from north west Germany for both hypervariable regions 1 (HV1) and 2 (HV2) and 100 polymorphic nucleotide positions (nps) were found, 63 in HV1 and 37 in HV2. A total of 100 different mtDNA lineages was revealed, of which 7 were shared by 2 individuals and 1 by 3 individuals. The probability of drawing a HV1 sequence match within the north west Germans or within published sets of south Germans and west Austrians is similar (within a factor of 2) to drawing a sequence match between any two of these three population samples. Furthermore, HV1 sequences of 700 male inhabitants of one village in Lower Saxony were generated and these showed a nearly linear increase of the number of different haplotypes with increasing number of individuals, demonstrating that the commonly used haplotype diversity measure (Nei 1987) for population samples tends to underestimate mtDNA diversity in the actual population.

Results of a collaborative study of the EDNAP group regarding mitochondrial DNA heteroplasmy and segregation in hair shafts

A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the distribution of mitochondrial DNA (mtDNA) heteroplasmy amongst the hairs of an individual who displays point heteroplasmy in blood and buccal cells. A second aim of the exercise was to study reproducibility of mtDNA sequencing of hairs between laboratories using differing chemistries, further to the first mtDNA reproducibility study carried out by the EDNAP group. Laboratories were asked to type 2 sections from each of 10 hairs, such that each hair was typed by at least two laboratories. Ten laboratories participated in the study, and a total of 55 hairs were typed. The results showed that the C/T point heteroplasmy observed in blood and buccal cells at position 16234 segregated differentially between hairs, such that some hairs showed only C, others only T and the remainder, C/T heteroplasmy at varying ratios. Additionally, differential segregation of heteroplasmic variants was confirmed in independent extracts at positions 16093 and the poly(C) tract at 302-309, whilst a complete A-G transition was confirmed at position 16129 in one hair. Heteroplasmy was observed at position 16195 on both strands of a single extract from one hair segment, but was not observed in the extracts from any other segment of the same hair. Similarly, heteroplasmy at position 16304 was observed on both strands of a single extract from one hair. Additional variants at positions 73, 249 and the HVII poly(C) region were reported by one laboratory; as these were not confirmed in independent extracts, the possibility of contamination cannot be excluded. Additionally, the electrophoresis and detection equipment used by this laboratory was different to those of the other laboratories, and the discrepancies at position 249 and the HVII poly(C) region appear to be due to reading errors that may be associated with this technology. The results, and their implications for forensic mtDNA typing, are discussed in the light of the biology of hair formation.

Subdural hygromas in abusive head trauma: pathogenesis, diagnosis, and forensic implications

Are subdural hygromas the result of abusive head trauma? CT and MR imaging represent important tools for the diagnosis of abusive head trauma in living infants. In addition, in-depth understanding of the pathogenesis of subdural hygromas is increasingly required by neuroradiologists, pediatricians, and forensic physicians. Therefore, the current knowledge on subdural hygromas is summarized and forensic conclusions are drawn. The most important diagnostic pitfalls, benign enlargement of the subarachnoid space, and chronic subdural hematoma, are discussed in detail. Illustrative cases from forensic practice are presented. Literature analysis indicates that subdural hygromas can occur immediately or be delayed. If other infrequent reasons can be excluded, the presence of subdural hygromas strongly suggests a posttraumatic state and should prompt the physician to search for other signs of abuse. To differentiate subdural hygromas from other pathologies, additional MR imaging of the infant's head is indispensable after initial CT scan.

Evaluating depressive symptoms and their impact on outcome in schizophrenia applying the Calgary Depression Scale

OBJECTIVE

To examine depressive symptoms, their course during treatment, and influence on outcome.

METHOD

Weekly Calgary Depression Scale for Schizophrenia ratings were performed in 249 inpatients with schizophrenia. Early response was defined as a 20% reduction in the total score of the Positive and Negative Syndrome Scale for Schizophrenia from admission to week 2, response as a 50% reduction in the total score of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) from admission to discharge and remission according to the consensus criteria.

RESULTS

Thirty six per cent of the patients were depressed at admission, with 23% of them still being depressed at discharge. Depressed patients scored significantly higher on the PANSS negative and general psychopathology subscore, featured more impairments in subjective well-being (P < 0.0001) and functioning (P < 0.0001). They suffered from more suicidality (P = 0.0021), and had greater insight into their illness (P = 0.0105). No significant differences were found regarding early response, response, and remission.

CONCLUSION

Patients with depressive symptoms should be monitored closely, given the burden of negative symptoms, their impairments in well-being and functioning and the threat of suicidality.

Mitochondrial DNA typing from human axillary, pubic and head hair shafts - success rates and sequence comparisons

The analysis of mitochondrial DNA (mtDNA) from shed hairs has gained high importance in forensic casework since telogen hairs are one of the most common types of evidence left at the crime scene. In this systematic study of hair shafts from 20 individuals, the correlation of mtDNA recovery with hair morphology (length, diameter, volume, colour), with sex, and with body localisation (head, armpit, pubis) was investigated. The highest average success rate of hypervariable region 1 (HV 1) sequencing was found in head hair shafts (75%) followed by pubic (66%) and axillary hair shafts (52%). No statistically significant correlation between morphological parameters or sex and the success rate of sequencing was found. MtDNA sequences of buccal cells, head, pubic and axillary hair shafts did not show intraindividual differences. Heteroplasmic base positions were observed neither in the hair shafts nor in control samples of buccal cells.

Sonographic examination of the apophysis of the iliac crest for forensic age estimation in living persons

The present study examines the applicability of ultrasound diagnostics in assessing the ossification processes of the apophysis of the Crista iliaca of the pelvis for the purposes of forensic age diagnostics in living persons. To this end, the apophyseal ossification stages were determined in 307 female and 309 male study participants aged between 10 and 25 years. In females, ossification stage I was identifiable at an age of 10.1 years at the earliest (x¯=11.8), ossification stage II at 11.2 years at the earliest (x¯=14.6), ossification stage III at 14.7 years at the earliest (x¯ =18.6), and ossification stage IV at 17.9 years at the earliest (x¯=22.7). In males, ossification stage I was observable from an age of 10.0 years (x¯=11.8), ossification stage II from 10.5 years (x¯=14.9), ossification stage III from 15.6 years (x¯=18.9), and ossification stage IV from 17.4 years (x¯=22.6). In forensic age estimation procedures in living persons, sonographic examination of the iliac crest apophysis makes it possible to minimise exposure of the individual to radiation in accordance with the existing legal basis for the use of X-rays on humans. In application areas with no legal basis to justify X-ray examinations, the accuracy of an age diagnosis can be improved by integrating skeletal maturity as a criterion.

Phylogenetic resolution of complex mutational features at Y-STR DYS390 in aboriginal Australians and Papuans

Y-chromosomal short tandem repeats (STRs) are used for the study of male aspects of human evolution as well as for forensic applications and paternity testing. Both applications require an understanding of the underlying mutational mechanisms that create variability. We describe complex mutations at the substructured DYS390 STR locus in 97 natives of the New Guinea/Australian region. Sequencing of short alleles in these populations indicates multirepeat deletions. All samples are further characterized using the five additional Y-STR loci DYS19, DXYS156-Y, DYS391, DYS392, and DYS393. Phylogenetic analysis of the resulting haplotypes yields ethnically specific clusters predating the settlement of Australia and Papua New Guinea (although archaic Homo sapiens or Homo erectus lineages are absent). The phylogeny confirms that DYS390 violates the stepwise mutation model and demonstrates that the DYS390 locus mutates relatively rapidly and retains its variability after structural change.