Use In Forensic Cases Research Articles

Determination of indirect heroin biomarkers in biological samples of heroin users

Heroin use is responsible for many drug-related deaths, so the determination of its biomarkers, except for 6-acetylmorphine, in biological samples, is of particular concern in toxicological laboratories worldwide, for a better investigation of these cases. Th use of 6-acetylmorphine as a heroin biomarker has some limitations due to its rapid bioconversion to morphine within a few hours, especially in blood samples. The need for new indirect biomarkers, like the ones that come from the processing of opium during the clandestine production of heroin, becomes imperative. A GC/MS method was developed and validated for the determination of meconin, thebaine, papaverine, acetylcodeine and noscapine, along with morphine, codeine and 6-acetylmorphine, in different biological samples of heroin users. For all analytes and all individual biological samples, the LOD and LOQ were 2.00 and 5.00 ng/mL, respectively, the calibration curves were linear (R2≥0.991) from 5.00 to 500.0 ng/mL, and absolute recoveries were higher than 91.9 %. The method was applied during the toxicological investigation of 34 forensic cases after positive immunoassay screening for opiates. The results indicate that meconin is the most frequently detected indirect biomarker of heroin use, as it was found in 91.2 % of all cases, whilst in 23.5 % of them no 6-acetylmorphine was detected. Papaverine was found in 67.6 % of all cases and is considered to be the second most important indirect biomarker of heroin use. The establishment of detecting meconin and papaverine in biological materials in parallel with the detection of morphine, codeine and 6-acetylmorphine can contribute to more conclusive results concerning heroin use in forensic cases.

Pregabalin Qualitative Detection in Turkish Forensic Cases Between 2017 to 2018

ABSTRACT Pregabalin (PGB) has been commonly subjected to diversion, from being a prescription drug to a recreational drug. In this study, pregabalin use (which is one of the substances subject to control in Turkey) and the concomitant use of other substances in cases admitted to the Izmir Forensic Medicine Institute was evaluated. Samples from 15,259 cases were screened, between June 2017 and December 2018, for the presence of PGB, and PGB positive cases were further analyzed. Of all cases screened, PGB was detected in 3.2% (n = 487). The mean age of PGB positive cases was 29.24 ± 10.34 years old (min: 14, max: 84), and 94% of them were male. Cannabis metabolite THC-COOH was the most common substance detected in the blood samples following PGB. Overall, 8 other substances were commonly used along with PGB. These substances were cannabis, morphine, hydromorphone, codeine, hydrocodone, heroin, paracetamol, and naproxen. Finally, we observed similar results in urine analysis. This research provides systematic data for PGB use in forensic cases in Turkey. The study findings indicate that PGB and multiple drug use increased over time, and providers should be particularly careful when prescribing PGB.

Forensic age assessment of late-term bovine fetuses

BackgroundTransporting pregnant cattle that have passed 90% or more of the expected gestation period (G90 threshold) is prohibited within the European Union. Therefore, there is a need to determine whether this threshold has been exceeded in late-gestation cows sent to slaughter. The aim of this study was to evaluate fetal parameters’ reliability for use in forensic age assessment of late-term Holstein fetuses.ResultsAnalysis of the gestation length of 2734 Holsteins that calved with a single liveborn fetus revealed a median gestation length of 278 days with 99% of parturitions occurring between day 261 and 290, corresponding to G90 thresholds of 235 and 261 days, respectively. The association between gestation length and neonatal body weight had an R2 of 0.27. The influence of fetal sex and cow parity on gestation length was ± 2 days. The eruption of incisor and canine teeth was assessed in preterm calves delivered by caesarean section (n = 52) and full-term neonatal calves (n = 54). Statistical analysis of tooth eruption data showed a statistically significant variation in fetal age at tooth eruption.ConclusionsDefining the G90 threshold for a cow not having reached parturition is challenging. Body weight was not found to be a reliable parameter for identifying fetuses beyond the G90 threshold. Statistical analysis of the association between fetal age and eruption through the gingival mucosa of incisor and canine teeth revealed significant variation, making tooth eruption a challenging parameter to use in forensic cases. Assessment of the evaluated parameters, therefore, cannot be considered a scientifically validated method to conclude definitively and beyond reasonable doubt whether or not a given fetus has passed the G90 threshold.

Uncertainty in Widmark calculations: ABV variation in packaged versions of the most popular beers in the UK

Forensic practitioners regularly use the Widmark equation to determine theoretical blood alcohol concentrations for use in cases involving alcohol. It is important with these calculations to determine the uncertainty associated with any result. Previous work has investigated the uncertainty in percent alcohol by volume (%ABV) from beers produced by small independent breweries in the UK but did not study the top selling beers in the UK. The top selling lagers and ales/bitters in the UK were identified by sales volume and the %ABV determined. These data was then used to determine the percent coefficient of variation (%CV) that should be used by forensic practitioners when constructing alcohol technical defence reports for use in forensic cases. These samples, from what may be described as ‘big’ brewers, were determined to have a smaller root mean square error (RMSE) (±0.1%v/v, n = 35), and %CV than those previously reported for beers produced by small, independent breweries in the UK. The results from this study shows that different RMSE's should be used for %ABV when determining the uncertainty of results from Widmark calculations depending if the drinks consumed have been from either ‘big’ brewers or small, independent breweries.

Enlarging the gene-geography of Europe and the Mediterranean area to STR loci of common forensic use: longitudinal and latitudinal frequency gradients

Background: Tetranucleotide Short Tandem Repeats (STRs) for human identification and common use in forensic cases have recently been used to address the population genetics of the North-Eastern Mediterranean area. However, to gain confidence in the inferences made using STRs, this kind of analysis should be challenged with changes in three main aspects of the data, i.e. the sizes of the samples, their distance across space and the genetic background from which they are drawn.Aim: To test the resilience of the gradients previously detected in the North-Eastern Mediterranean to the enlargement of the surveyed area and population set, using revised data.Subjects and methods: STR genotype profiles were obtained from a publicly available database (PopAffilietor databank) and a dataset was assembled including >7000 subjects from the Arabian Peninsula to Scandinavia, genotyped at eight loci. Spatial principal component analysis (sPCA) was applied and the frequency maps of the nine alleles which contributed most strongly to sPC1 were examined in detail.Results: By far the greatest part of diversity was summarised by a single spatial principal component (sPC1), oriented along a SouthEast-to-NorthWest axis. The alleles with the top 5% squared loadings were TH01(9.3), D19S433(14), TH01(6), D19S433(15.2), FGA(20), FGA(24), D3S1358(14), FGA(21) and D2S1338(19). These results confirm a clinal pattern over the whole range for at least four loci (TH01, D19S433, FGA, D3S1358).Conclusions: Four of the eight STR loci (or even alleles) considered here can reproducibly capture continental arrangements of diversity. This would, in principle, allow for the exploitation of forensic data to clarify important aspects in the formation of local gene pools.

Dynamics of the oral microbiota as a tool to estimate time since death.

The oral cavity harbors one of the most diverse microbiomes in the human body. It has been shown to be the second most complex in the body after the gastrointestinal tract. Upon death, the indigenous microorganisms lead to the decomposition of the carcass. Therefore, the oral cavity and gastrointestinal tract microbiomes play a key role in human decomposition. The aim of the present study is to monitor the microbiome of decaying bodies on a daily basis and to identify signature bacterial taxa, that can improve postmortem interval estimation. Three individuals (one male and two female) donated to the University of Tennessee Forensic Anthropology Center for the W.M. Bass Donated Skeletal Collection were studied. Oral swab samples were taken daily throughout the different stages of cadaveric putrefaction. DNA was extracted and analyzed by next-generation sequencing techniques. The three cadavers showed similar overall successional changes during the decomposition process. Firmicutes and Actinobacteria are the predominant phyla in the fresh stage. The presence of Tenericutes corresponds to bloat stage. Firmicutes is the predominant phylum in advanced decay, but the Firmicutes community is a different one from the predominant Firmicutes of the fresh stage. This study depicts the thanatomicrobiome successional changes in the oral cavity, and highlights its potential use in forensic cases as a quantitative and objective approach to estimate postmortem interval, from an ecological rationale.

Cytochrome c oxidase subunit 1-based human RNA quantification to enhance mRNA profiling in forensic biology

RNA analysis offers many potential applications in forensic science, and molecular identification of body fluids by analysis of cell-specific RNA markers represents a new technique for use in forensic cases. However, due to the nature of forensic materials that often admixed with nonhuman cellular components, human-specific RNA quantification is required for the forensic RNA assays. Quantification assay for human RNA has been developed in the present study with respect to body fluid samples in forensic biology. The quantitative assay is based on real-time reverse transcription-polymerase chain reaction of mitochondrial RNA cytochrome c oxidase subunit I and capable of RNA quantification with high reproducibility and a wide dynamic range. The human RNA quantification improves the quality of mRNA profiling in the identification of body fluids of saliva and semen because the quantification assay can exclude the influence of nonhuman components and reduce the adverse affection from degraded RNA fragments.

A Retrospective Evaluation of Psychiatric Comorbidity and Substance Use in Forensic Cases Admitted to Emergency Service

Objectives: Forensic cases are commonly encountered cases with high legal responsibility. In addition to low socio-economic status and level of income, psychiatric diagnoses such as substance and alcohol abuse, personality disorders, some axis 1 disorders have been reported to increase violent behavior. In this retrospective study, we evaluated substance abuse, psychiatric comorbidity, and relationship between type of forensic report and psychiatric diagnoses in forensic cases. Methods: Data regarding sociodemographic characteristics, forensic circumstances and psychiatric history of forensic cases admitted to Van Military Hospital Department of Emergency between January 2012-April 2014 recruited from hospital database. Results: One hundred and four(23.6%) of the 441 patients had a psychiatric history. There was no significant difference in terms of injury severity score between the group with psychiatric diagnose history and the group with no psychiatric history(p=0.06). Adjustment disorder and B cluster personality disorder were the most prevalent psychiatric diagnoses in study population. Assault(52.9%), intoxication(26%) and firearm/sharp object injuy (17.3%) were the most encountered forensic circumstances in those with psychiatric history as assault and intoxication were found to be significantly higher than other events in this population(p<0.05). Assessment of relationship between type of forensic event and psychiatric diagnoses showed assault, firearm/sharp object injuy, and intoxication were statistically significant in B cluster disorder patients while intoxication was found to be significant in anxiety diagnosed patients(p<0.05). Substance use was determined in fourty-six patients(44.2%) of those with psychiatric history while a significant relationship was found between substance use and firearm/sharp object injuy in this population(p=0.03). Conclusion: Detailed evaluation of psychiatric comorbidity and substance use with appropriate psychiatric therapeutic interventions could have a positive impact on management of forensic cases.

Anthropological facial approximation in three dimensions (AFA3D): computer-assisted estimation of the facial morphology using geometric morphometrics.

This study presents Anthropological Facial Approximation in Three Dimensions (AFA3D), a new computerized method for estimating face shape based on computed tomography (CT) scans of 500 French individuals. Facial soft tissue depths are estimated based on age, sex, corpulence, and craniometrics, and projected using reference planes to obtain the global facial appearance. Position and shape of the eyes, nose, mouth, and ears are inferred from cranial landmarks through geometric morphometrics. The 100 estimated cutaneous landmarks are then used to warp a generic face to the target facial approximation. A validation by re-sampling on a subsample demonstrated an average accuracy of c. 4mm for the overall face. The resulting approximation is an objective probable facial shape, but is also synthetic (i.e., without texture), and therefore needs to be enhanced artistically prior to its use in forensic cases. AFA3D, integrated in the TIVMI software, is available freely for further testing.

The inflammatory cellular constituents of foetal and infant leptomeninges: a survey of hospital-based autopsies without trauma

ObjectivesNotwithstanding the lack of definitive evidence from studies conducted to date, inflammatory infiltrates and iron deposition in the leptomeninges are routinely used as forensic markers of traumatic brain injury. We investigated the presence of these forensic markers of trauma in neonates and infants, with the objective of determining their suitability for use in forensic cases.MethodsLeptomeninges derived from non-traumatic deaths were studied. Thirty-three cases were divided into groups 1 and 2, according to set age groups. Inflammatory cells and iron in these groups were quantified.ResultsCD45, CD68 and CD163 positive inflammatory cells were identified in the leptomeninges of sections of the cerebellum, brain stem and cortex of all 33 cases of non-traumatic infant deaths surveyed in this study. There were no significant differences between the two groups. Iron was found in the leptomeninges in several cases, even those without recent haemorrhage. Overall within the two subgroups, the numbers of inflammatory cells and iron containing cells were not significantly different.ConclusionThese findings demonstrate that inflammatory cells and iron in the leptomeninges can be found in natural and non-traumatic conditions. Further, two cases with no reported neuropathology demonstrated the presence of inflammatory cells and iron. Thus, cautious interpretation of the presence of inflammatory cells and iron containing cells in forensic paediatric cases is recommended.

Polymorphisms analysis and evaluation of five non-CODIS STR loci in a population sample of immigrants living in Northern Italy

ENFSI recently introduced in forensic DNA typing five new STRs loci (D10S1248, D22S1045, D2S441, D1S1656, D12S391) not included in CODIS. It is necessary to obtain data regarding allele frequencies for these five loci in different populations, allowing their use in forensic cases. In this study two groups of individuals of two of the main ethnic groups living in Northern Italy, the Albanians and the Indo-Pakistanis, were typed using the commercial kit AmpFlSTR® NGM; allelic frequencies and forensic parameters were calculated.

Validation of a 17-locus Y-STR multiplex system

Internal validation of a commercial 17-locus Y-STR system (AmpFlSTR ® Yfiler™, Applied Biosystems) has been performed on the ABI PRISM ® 3130 Genetic Analyzer for use in forensic cases. The Yfiler™ kit was validated according to SWGDAM guidelines. Our results show that it is possible to obtain full profiles with as little as 30 pg of male DNA even in the presence of 20,000-fold amounts of female DNA. Reaction volume was optimized for 10 μl. Male–male mixtures yielded full profiles of the minor contributor with 10-fold excess of the major contributor. Stutter values for each locus were determined from data generated for the population study which included Y-STR profiles from 156 caucasian males from the Montreal and Lac St.-Jean areas of Québec, Canada. The study recorded 141 different haplotypes of which 131 were unique with a haplotype diversity of 0.9965. A number of non-probative forensic samples from rape kit epithelial fractions and fingernail scrapings were also successfully tested.

A new 39-plex analysis method for SNPs including 15 blood group loci

A novel 39-plex typing system for single nucleotide polymorphisms (SNPs) has been developed. This multiplex approach has the advantage of being able to type 38 autosomal SNPs and one sex-discriminating base exchange site on the X and Y chromosomes rapidly and simultaneously. The SNP loci on the autosomes, which we examined, contain 15 loci distributed on blood type genes: three on RhCE, two each on Km and Gc, and one each on Duffy, AcP1, Tf, MN, GPT, EsD, PI, and Kidd genes. Thirty-seven genomic DNA fragments containing a total of 38 SNPs and one sex-discriminating site were amplified in one multiplex PCR reaction. Following the reaction, single nucleotide primer extension reaction was performed by dividing these SNP loci into five groups. The SNP type of each of the 39 loci was determined at one time by capillary electrophoresis using the newly designed multi-injection method. The combined PD (power of discrimination) of this typing system was (1–1.1)×10 −14, and the MEC (mean exclusion chance) was 0.9990. We applied this system to forensic cases, including 16 paternity testing cases (13 non-exclusion and three exclusion cases) and one personal identification case. For the paternity testing cases, the highest Essen–Möller’s W-value was 0.9999995. The pM (matching probability) of the personal identification case was 2.22×10 −17. These data showed that this system was an excellent tool for use in forensic cases of paternity testing and personal identification.

Analysis of Morphine by RIA and HPLC in Fingernail Clippings Obtained from Heroin Users

Heroin is abused around the world and is frequently reported as the cause of death in overdose cases. Analysis of morphine in hair has been used in the past in forensic toxicology to study the addiction history of heroin addicts. The purpose of the present study was to evaluate the usefulness of the nail as an analytical specimen in the identification and quantification of morphine in fingernail clippings of known heroin users. Fingernail clippings were obtained from 26 consenting patients of the Glasgow Drug Problem Service. At the time of sampling, the participants provided answers to a questionnaire regarding their drug use patterns. Samples were decontaminated by sonication in SDS, deionized water and methanol, and the methanolic washes were screened for analyte presence. The washed nail clippings were then hydrolyzed and extracted. RIA was used for the screening and HPLC for the confirmation of morphine. Positive RIA results were obtained with nail clippings from 25 of the 26 heroin users. The levels ranged from 0.06 to 4.69 ng/mg with a mean morphine concentration of 1.67 ng/mg. HPLC results were positive for 22 of the 26 nail samples. The mean morphine level by HPLC was 2.11 ng/mg with a range from 0.14 to 6.90 ng/mg. Based on these results, we suggest that nails have the potential of becoming a powerful alternative to hair for the detection of past heroin use in forensic cases.