The analysis of an intracerebral hematoma for drugs of abuse

Toxicological investigations were performed on an intracerebral hematoma, antemortem blood, and postmortem blood of an individual who was found unresponsive in his home. The hematoma was found to have ethanol at a concentration of 0.05% (w/v), and benzoylecgonine (a cocaine metabolite) was also confirmed at a concentration of 0.43 mg/L by specific analysis using gas chromatography/mass spectrometry (GC/MS). These results enabled the pathologist to record the cause of death as intracerebral hemorrhage due to acute cocaine intoxication.     

The successful DNA typing of samples following a thermal cycler power loss

An approach for generating DNA profiles when critical samples have been consumed and a power outage occurs during the polymerase chain reaction (PCR) amplification reaction is described. This study demonstrates that a complete and accurate DNA short tandem repeat profile can be obtained: (1) when single source DNA samples are amplified for 26, 27, or 28 cycles using the Profiler Plus and COfiler Amplification Kits after an interruption in amplification, (2) from mock samples when PCR amplification has been interrupted early (after five cycles) or late (after 18 cycles) and the sample is subjected to an additional round of amplification, even after incubation of the sample at room temperature overnight, and (3) from nonprobative casework samples interrupted after approximately 18 cycles of amplification, an overnight incubation at room temperature and subjected to one or two additional rounds of PCR amplification for approximately 26 total cycles. Samples interrupted before five completed cycles and subjected to additional PCR cycles yielded variable results.     

The determination of nicotine and sulfate in supermarket ground beef adulterated with Black Leaf 40

In December 2002, approximately 250 lbs. of ground beef was adulterated with nicotine sulfate by a supermarket employee and subsequently sold to the public. Soon afterward, reports of illness associated with ground beef purchased at a single store were identified. Authorities suspected the ground beef was tainted with Black Leaf 40, a banned pesticide containing approximately 40% nicotine as nicotine sulfate. Ground beef submitted to our laboratory was analyzed in concert by high performance liquid chromatography-ultraviolet detection (HPLC-UV), gas chromatography-mass spectrometry (GC-MS), and high performance anion exchange chromatography with suppressed conductivity detection. GC-MS was used to identify the samples that contained nicotine. The nicotine was confirmed and quantitated by HPLC-UV. The sulfate was identified and quantitated by high performance anion exchange chromatography with suppressed conductivity detection. Our analysis revealed that the raw tainted beef contained about 350 mg/kg nicotine free base, a potentially lethal dose of nicotine per serving for an adult. Additionally, we found elevated sulfate levels in the samples that tested positive for nicotine, providing evidence that nicotine sulfate was the probable adulterant.     

A collaborative study of the EDNAP group regarding Y-chromosome binary polymorphism analysis

A collaborative study was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the performance of Y-chromosome binary polymorphism analysis in different European laboratories. Four blood samples were sent to the laboratories, to be analysed for 11 Y-chromosome single nucleotide polymorphisms (SNPs): SRY-1532, M40, M35, M213, M9, 92R7, M17, P25, M18, M153 and M167. All the labs were also asked to submit a population study including these markers. All participating laboratories reported the same results, indicating the reproducibility and robustness of Y-chromosome SNP typing. A total of 535 samples from six different European populations were also analysed. In Galicia (NW Spain) and Belgium, the most frequent haplogroup was R1b*(xR1b1,R1b3df). Haplogroup F*(xK) is one of the most frequent in Austria and Denmark, while the lowest frequency appear in Belgium. Haplogroup frequencies found in this collaborative study were compared with previously published European Y-chromosome haplogroup data.