Concordance testing between Powerplex ESI 16 Fast System and VeriFiler Express.

DNA profiles generated by different STR kits may show different alleles for identical amplified loci. This well-known phenomenon affects the smooth transition of data generated by new STR kits to a database or casework laboratory or cross-laboratory comparison of STR profiles. As in other DNA databases throughout the world, it has become clear that the number of the analyzed loci should be expanded for a variety of reasons, such as partial profiles resulting from low copy-number DNA template or degraded samples, working with mixtures or when prevalence of familial inbreeding. In the course of introducing a new STR kit, VeriFiler™ Express (Applied Biosystems, Foster City, CA, USA), we compared genotyping data of 1568 samples amplified by the VeriFiler™ Express with the data generated on the same samples by the Powerplex™ ESI FAST (Promega, Madison WI, USA) kit. Discordance was noted in 20 samples (1.27%), 14 (0.89%) of them showing allele dropout mismatch and six (0.38%) showing an additional fixed-size third allele. These rates are well above the reported rates of 0.4% for this kit. Since correct genotyping and accurate consistent allele assignment is of paramount importance, it seems timely to recommend for DNA laboratories and genetic-match search systems to take these possible inconsistencies into account.

Functional effects of synthetic cannabinoids versus Δ9 -THC in mice on body temperature, nociceptive threshold, anxiety, cognition, locomotor/exploratory parameters and depression.

Synthetic cannabinoids are psychoactive substances designed to mimic the euphorigenic effects of the natural cannabis. Novel unregulated compounds appear once older compounds become illegal. It has been previously reported that synthetic cannabinoids are different than Δ9 -tetrahydrocannabinol (Δ9 -THC) as they have chemical structures unrelated to Δ9 -THC, different metabolism and, often, greater toxicity. This study aimed to investigate the effects of three novel synthetic cannabinoids and pure Δ9 -THC on body temperature, nociceptive threshold, anxiety, memory function, locomotor and exploratory parameters, and depression. We performed a battery of behavioural and motor tests starting 50 minutes post i.p. injection of each drug to adult ICR mice. The synthetic cannabinoids that were used are AB-FUBINACA, AB-CHMINACA and PB-22. All synthetic cannabinoids and Δ9 -THC caused hypothermia, but only Δ9 -THC induced a clear antinociceptive effect. All synthetic cannabinoids and Δ9 -THC caused decreased anxiety levels, spatial memory deficits and decreased exploratory behaviour as measured in the elevated plus maze, Y-maze and staircase paradigm, respectively. However, all synthetic cannabinoids but not Δ9 -THC demonstrated decreased locomotor activity in the staircase test. Moreover, only AB-FUBINACA and Δ9 -THC affected the gait balance and grip strength of the mice as was assessed by the latency time to fall from a rod. In the forced swimming test, PB-22 caused elevated depression-like behaviour while AB-FUBINACA induced a reversed effect. These results suggest varied effects among different synthetic cannabinoids and Δ9 -THC. Further studies are needed to characterize the overall effects and differences between these synthetic cannabinoids and Δ9 -THC.

2-methiopropamine, a thiophene analogue of methamphetamine: studies on its metabolism and detectability in the rat and human using GC-MS and LC-(HR)-MS techniques.

2-Methiopropamine [1-(thiophen-2-yl)-2-methylaminopropane, 2-MPA], a thiophene analogue of methamphetamine, is available from online vendors selling "research chemicals." The first samples were seized by the German police in 2011. As it is a recreational stimulant, its inclusion in routine drug screening protocols should be required. The aims of this study were to identify the phase I and II metabolites of 2-MPA in rat and human urine and to identify the human cytochrome-P450 (CYP) isoenzymes involved in its phase I metabolism. In addition, the detectability of 2-MPA in urine samples using the authors' well-established gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-linear ion trap-mass spectrometry (LC-MS(n)) screening protocols was also evaluated. The metabolites were isolated from rat and human urine samples by solid-phase extraction without or following enzymatic cleavage of conjugates. The phase I metabolites, following acetylation, were separated and identified by GC-MS and/or liquid chromatography-high-resolution linear ion trap mass spectrometry (LC-HR-MS(n)) and the phase II metabolites by LC-HR-MS(n). The following major metabolic pathways were proposed: N-demethylation, hydroxylation at the side chain and at the thiophene ring, and combination of these transformations followed by glucuronidation and/or sulfation. CYP1A2, CYP2C19, CYP2D6, and CYP3A4 were identified as the major phase I metabolizing enzymes. They were also involved in the N-demethylation of the analogue methamphetamine and CYP2C19, CYP2D6, and CYP3A4 in its ring hydroxylation. Following the administration of a typical user's dose, 2-MPA and its metabolites were identified in rat urine using the authors' GC-MS and the LC-MS(n) screening approaches. Ingestion of 2-MPA could also be detected by both protocols in an authentic human urine sample.

New cathinone-derived designer drugs 3-bromomethcathinone and 3-fluoromethcathinone: studies on their metabolism in rat urine and human liver microsomes using GC-MS and LC-high-resolution MS and their detectability in urine.

3-Bromomethcathinone (3-BMC) and 3-Fluoromethcathinone (3-FMC) are two new designer drugs, which were seized in Israel during 2009 and had also appeared on the illicit drug market in Germany. These two compounds were sold via the Internet as so-called "bath salts" or "plant feeders." The aim of the present study was to identify for the first time the 3-BMC and 3-FMC Phase I and II metabolites in rat urine and human liver microsomes using GC-MS and LC-high-resolution MS (HR-MS) and to test for their detectability by established urine screening approaches using GC-MS or LC-MS. Furthermore, the human cytochrome-P450 (CYP) isoenzymes responsible for the main metabolic steps were studied to highlight possible risks of consumption due to drug-drug interaction or genetic variations. For the first aim, rat urine samples were extracted after and without enzymatic cleavage of conjugates. The metabolites were separated and identified by GC-MS and by LC-HR-MS. The main metabolic steps were N-demethylation, reduction of the keto group to the corresponding alcohol, hydroxylation of the aromatic system and combinations of these steps. The elemental composition of the metabolites identified by GC-MS could be confirmed by LC-HR-MS. Furthermore, corresponding Phase II metabolites were identified using the LC-HR-MS approach. For both compounds, detection in rat urine was possible within the authors' systematic toxicological analysis using both GC-MS and LC-MS(n) after a suspected recreational users dose. Following CYP enzyme kinetic studies, CYP2B6 was the most relevant enzyme for both the N-demethylation of 3-BMC and 3-FMC after in vitro-in vivo extrapolation.

The influence of a possible contamination of the victim's clothing by gunpowder residue on the estimation of shooting distance.

A study was conducted to assess the influence of a possible contamination of the victim's clothing by gunpowder residue on the estimation of shooting distance. The study was focused on the scenario in which the contamination might be caused by the surface on which the shot victim could fall. Contamination of two types of textile was examined after contact with two types of surfaces. One round was fired above those surfaces (the line of firing parallel to the surface) prior to the contact. It was found that few gunpowder residue particles could be transferred to the clothing. These findings should be taken into account when interpreting results for shooting distance estimation in cases when a minute quantity of gunpowder residue particles is found around the bullet entrance hole.

Recovery and detection of urea nitrate in traces.

Urea nitrate (uronium nitrate, UN) is a powerful improvised explosive, frequently used by terrorists in the Israeli arena. It was also used in the first World Trade Center bombing in New York in February 1993. It is difficult to identify UN in postexplosion debris, because in the presence of water it readily decomposes to its original components, urea and nitric acid. A method for the recovery and detection of urea nitrate in traces is described. The residues are extracted with hot acetone, and the extract chromatographed on chromosorb G-HP. The eluent is analyzed by liquid chromatography mass spectrometry using atmospheric pressure chemical ionization (APCI). By applying this technique, we were able to identify urea nitrate in actual exhibits. It was found that UN can be also formed during the analytical procedure, by certain combinations of urea, nitrate ions, and a source of protons and, hence, the presence of the characteristic adduct ion does not necessarily indicate an "authentic" urea nitrate. Several solutions are suggested to overcome this ambiguity.

A novel method for the analysis of discharged smokeless powder residues.

A novel method for the estimation of intermediate-long firing distance range is proposed. The method is based on the characterization and chemical analysis of the smokeless powder particles on the target. An adhesive lifter is applied to collect the suspected gunshot residues (GSRs) from the surface of an object, and a Modified Griess Test (MGT) is carried out after alkaline hydrolysis on the adhesive lifter. Visualized particles are removed from the adhesive lifter under a microscope. Two systems are used for the analysis of organic discharge residues from the smokeless powder: (1) gas chromatography/thermal energy analysis (GC/TEA) for the analysis of nitroglycerine (NG) and 2,4-dinitrotoluene (2,4-DNT), (2) gas chromatography/mass spectrometry (GC/MS) for the identification of organic components such as DNT, NG, and some stabilizers. By using this procedure and confirming that the suspected particles are indeed GSR, one can estimate the intermediate-long firing distance of c. 0.75-3 m in the presence of very few particles and provide information for the classification of ammunition type in casework.

A possible source of reference DNA from archived treated adhesive lifters.

During the course of a double murder trial, it became apparent that the two adhesive lifters from the two cadavers had been mislabeled before being presented in court. The question was raised whether DNA testing from the biological material remaining attached to the lifters could resolve this mix-up. In fatal shooting cases where a bullet has been fired through a body surface, an adhesive lifter is applied directly to the entrance wound. The total nitrite residues, as well as biological material surrounding the wound (blood, hair, tissue) are transferred to the adhesive lifter. The nitrite residues are used for estimating firing distance. In a worst-case scenario, the biological material on the lifter may be the only remaining reference material from a victim. In this paper, we examined whether the biological material retrieved from adhesive lifters could be used for DNA typing after the lifters had been treated for GSR pattern. In as much as the biological material found on the lifters can be typed and profiled following physical and chemical treatment, we submit that archived adhesive lifters can be used as a future source of reference DNA from cadavers where no other sample is available.