Interrogation of short tandem repeats using fluorescent probes and melting curve analysis: A step towards rapid DNA identity screening

Current forensic DNA profiling methods rely on the analysis of samples at specialised laboratories with an average turnaround time of several days. The ability to rapidly determine a partial profile of short tandem repeats at the point-of-arrest would be of great benefit to police forces around the world, for example enabling a suspect to be rapidly included or excluded from an investigation. We have developed a homogeneous PCR method for the interrogation of STR loci utilising fluorescent oligonucleotide probes and melting curve analysis. Alleles of the D18S51, TH01 and D8S1179 loci were differentiated and identified on the basis of target length and probe melting temperature. Assay performance was evaluated by comparing melting peak data with the AmpFlSTR^® SGM Plus^® system. The method is compatible with direct analysis of unpurified buccal swab samples, enabling a partial STR profile to be generated within 1 h.     

Chemico-toxicological study of fluoxetine

Selected aspects of chemico-toxicological analysis of the tranquillizer drug fluoxetine are described. Optimal conditions for fluoxetin extraction from internal organs and biological fluids (blood, urine) are specified and methods proposed for its detection and quantitation including TLC, UV SPM, and HPLC. The proposed methods were verified using laboratory animals and materials for expert examination.     

Stature estimation from foot dimensions

Identification of an individual is the mainstay in forensic investigations. The dimensions of the foot have been used for the determination of sex, age, and stature of an individual. The present study examines the relationship between stature and foot dimensions among Gujjars, a North Indian endogamous group. Stature, foot length and foot breadth of 200 subjects comprising 100 males and 100 females were measured. Statistical analyses indicated that the bilateral variation was insignificant for all the measurements except foot breadth in males (p<0.01). Sex differences were found to be highly significant for all the measurements (p<0.01). Linear and multiple regression equations for stature estimation were calculated using the aforementioned variables and multiplication factors were computed. The correlation coefficients between stature and foot dimensions were found to be positive and statistically highly significant. The highest correlation coefficient between stature and foot length in males and foot breadth in females indicates that the foot length provides the highest reliability and accuracy in estimating stature of an unknown male and foot breadth in a female. Prediction of stature was found to be most accurate by multiple regression analysis.     

Comparison of the validity of three dental methods for the estimation of age at death

The aim of the present study was to compare the accuracy, precision, and bias of two macroscopic and one histological age at death estimation methods on human teeth. The sample was comprised of 67 permanent teeth, obtained from 37 individuals aged 20-91 years. Age was predicted according to the methods proposed by Lamendin et al. (LAM), Bang and Ramm (BR), and the quantification of tooth cementum annulations (TCA). TCA was found to be most accurate in all age groups. Its mean absolute error of the estimated age was about half as high as the mean absolute error for both LAM and BR. BR achieved approximately the same mean absolute error as TCA for old adults only. LAM displayed the highest precision in the young and the old age group whereas TCA was more precise in the middle age group. TCA was found to be the most precise method when the precision was calculated for all ages. Considering the bias, all methods displayed a tendency to overestimate age in young and to underestimate it in old specimens. The exception to this rule was TCA, which provided unbiased estimates for young adults. The higher accuracy and precision recommends favouring TCA over LAM and BR, provided that the required know-how and equipment are available.     

Hair analysis to document non-fatal pesticide intoxication cases

We reported two non-fatal cases of intoxication with pesticides namely alachlor and carbofuran. Hair stand samples were collected from two men approximately 1 year after alachlor intoxication for case 1, and 14 days after the last exposure for case 2. Hair analysis was performed using a liquid chromatography-tandem mass spectrometry method. In case 1, alachlor was detected in the 5 analysed hair segments (concentrations between 12 and 136 pg/mg) and its metabolites were not detected. In case 2, carbofuran and its main metabolite (3-hydroxycarbofuran) were detected in the hair strand (global analysis) at the concentrations of 207 and 164 pg/mg, respectively. However, additional data are required in order to interpret such results.     

Fatal intoxication due to tramadol alone: case report and review of the literature

Poisoning may also lead to both coma and multiple organ failure, also in youngsters without a known major medical history. As not all toxic agents are routinely screened when a poisoning is suspected, it is useful to consider less frequently encountered poisons in certain cases. We describe the occurrence of asystole and multiple organ failure which occurred in a young man after a suspected tramadol overdose. The tramadol concentration on admission in the ICU was indeed 8 microg/ml (mg/l), far above the therapeutic range. Subsequently, the patient developed severe acute liver failure, finally leading to death. Post-mortem toxicology did not reveal any other poison responsible for this unfavourable course as only very high serum and tissue tramadol and desmethyltramadol concentrations were found. Only a few fatal poisonings attributable to tramadol alone, as observed in our case, have been reported. An overview of these cases is presented.     

Perceptions of repressed memories: A reappraisal

College students read a trial summary of a sexual abuse case. The victim in the case either claimed that (a) her memory for the abuse had been repressed for 20 years and only recently recovered during therapy, or (b) she consciously remembered the abuse for 20 years but never discussed it until recently in therapy. Participants were significantly more likely to convict the defendant when the testimony was described as nonrepressed (67%) versus repressed (58%). This effect was not modified by the age of the victim at the time the alleged abuse occurred (either 3, 8, or 13 years of age), although the younger and older victims were significantly less believable than the 8-year-old victim. Compared to female participants, male participants were significantly less likely to convict the defendant and rated the victim as significantly less believable. These findings are discussed in the context of recent research on juror reactions to repressed memory testimony.