Evaluation of ephedrine, pseudoephedrine and phenylpropanolamine concentrations in human urine samples and a comparison of the specificity of DRI amphetamines and Abuscreen online (KIMS) amphetamines screening immunoassays

The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common.     

Systematic differences in electropherogram peak heights reported by different versions of the GeneScan software

DNA profiling using STRs on the 310 and 3100 Genetic Analyzers routinely generates electropherograms that are analyzed with the GeneScan software available from the instrument's manufacturer, Applied Biosystems. Users have been able to choose from three different smoothing options that have been known to result in significant differences in the peak heights that are reported. Improvements in the underlying algorithm of the most recent version of the software also result in significant and somewhat predictable differences in peak height values. Laboratories that have performed validation studies using older versions of GeneScan should either reanalyze the data generated in those validation studies with the newest version of the software or otherwise take into consideration the systematically higher peak height values obtained as they begin following the recommendation of the manufacturer and use the new algorithm.     

Does the expert witness fit the crime? Injury to a child by starvation--a dietitian's testimony

After the death of their four-month-old infant, the parents were charged with injury to a child by starvation. The medical examiner documented blunt force trauma and severe malnutrition at autopsy, but the cause of death was undetermined. The legal team hired a neonatal dietitian who was able to determine that impaired growth only occurred when the infant was in the care of his parents. This information, along with other testimony, established that the lack of nutrition compromised this infant's ability to grow and develop normally, and thus contributed to the infant's death. A jury found the father guilty of injury to a child with intent, and was sentenced to 50 years in prison. The mother agreed to a plea bargain serving 25 years. The purpose of this report is to offer insight, information, and facts from this case for the benefit of others.     

Tramadol (Ultram) concentrations in death investigation and impaired driving cases and their significance

We reviewed a series of 66 deaths in Washington State between 1995-2000 in which tramadol (Ultram and Ultracet, Ortho-McNeil) was detected in the decedent's blood, in order to assess the role tramadol was determined to have played. Additionally, we reviewed a series of 83 impaired driving cases in which tramadol was detected in order to establish a non-lethal blood tramadol concentration reference range. In both populations, tramadol was consistently found together with other analgesic, muscle relaxant, and CNS depressant drugs. Death was rarely attributable to tramadol alone. However, tramadol may be a significant contributor to lethal intoxication when taken in excess with other drugs, via the potential interaction with serotonergic antidepressant medications, as well as the potential for increased CNS depression. Although the incidence of tramadol detection has increased consistently over the last eight years, there is no evidence of a corresponding increase in the number of cases in which death was attributed solely to tramadol. Blood drug concentrations in many deaths exceeded the therapeutic serum range of 0.28-0.61 mg/L; however, the concentrations overlapped almost completely with the range identified in living subjects arrested for impaired driving. These findings suggest caution in the interpretation of blood tramadol concentrations outside of the recognized therapeutic range. It also suggests that the drug, even when used in moderate excess, is not a principle cause of death in suicidal or accidental deaths.     

Use of MDA (the "love drug") and methamphetamine in Toronto by unsuspecting users of ecstasy (MDMA)

It has recently been reported that purity of illicit tablets of ecstasy (MDMA) is now high. Our objective was to confirm whether hair of drug users, who request only ecstasy from their supplier, contains MDMA in the absence of other drugs. GC-MS analysis of scalp hair segments disclosed the presence of MDMA in 19 of 21 subjects and amphetamine/methamphetamine in eight subjects. Surprisingly, seven subjects had hair levels of the MDMA metabolite, MDA, equal to or greater than those of MDMA, suggesting use of MDA in addition to that of MDMA. These amphetamine derivatives might be included by clandestine laboratories to enhance effects of the drug cocktail or because of a perception that MDA synthesis might be simpler than that of MDMA. Drug users and investigators examining possible brain neurotoxic effects of MDMA need to consider that "ecstasy" tablets can contain MDA and methamphetamine despite no demand for the drugs.     

A genetic basis for anomalous band patterns encountered during DNA STR profiling

Since 1995 the Forensic Science Service (FSS) has carried out DNA profiling of reference samples for the UK National DNA Database and in forensic casework using two multiplex STR profiling systems. During this period, profiles with anomalous banding patterns, although comparatively rare, have been encountered regularly. The FSS has collected instances of triallelic patterns and aberrant diallelic patterns. A systematic examination of these patterns has provided insight into their underlying genetic cause. The triallelic patterns could be classified into two types based on the relative intensities of their component alleles. In the Type 1 pattern the alleles were of uneven intensity, whereas in the Type 2 pattern, all three alleles were of even intensity. Evidence is presented that the more frequent Type 1 pattern is the result of somatic mutation at a heterozygous locus, and the Type 2 pattern is the result of a localized chromosomal rearrangement at a heterozygous locus. Directly from the Type 1 pattern, it was possible to deduce the size difference between the progenitor and mutated allele. All mutational changes were found to be multiples of four nucleotides, suggesting the loss or addition of one or more tetrameric repeat units. Aberrant diallelic patterns were identified by analysts due to an unexpectedly large difference in intensity between alleles at a heterozygous locus. While some of these diallelic patterns are likely caused by the same genetic phenomena described above occurring at a homozygous locus, others are demonstrated to be caused by a mutation in the primer binding sequence, leading to a reduction in amplification efficiency of one allele. It is concluded that based on a visual inspection of a profile, it is possible to infer a likely genetic basis directly from the triallelic pattern. By contrast, the aberrant diallelic patterns can be due to any one of a number of possible genetic effects.     

Y-SNP typing of U.S. African American and Caucasian samples using allele-specific hybridization and primer extension

Multiplex analysis of genetic markers has become increasingly important in a number of fields, including DNA diagnostics and human identity testing. Two methods for examination of single nucleotide polymorphisms (SNPs) with a potential for a high degree of multiplex analysis of markers are primer extension with fluorescence detection, and allele-specific hybridization using flow cytometry. In this paper, we examined 50 different SNPs on the Y-chromosome using three primer extension multiplexes and five hybridization multiplex assays. For certain loci, the allele-specific hybridization method exhibited sizable background signal from the absent alternate allele. However, 100% concordance (>2000 alleles) was observed in ten markers that were typed using both methods. A total of 18 unique haplogroups out of a possible 45 were observed in a group of 229 U.S. African American and Caucasian males with the majority of samples being assigned into 2 of the 18 haplogroups.     

Interpretation of postmortem change in cadavers in Spain

Estimating time since death is especially difficult in the examination of poorly preserved cadavers and depends on the experience of the examiner and comparison with previously documented cases showing similar characteristics. The present study reports on information obtained over the past ten years through the work of the Laboratorio de Antropología y Odontología Forense (LAF) of the Instituto Anatómico Forense de Madrid, Spain, in particular evaluating how the type of fracture influences postmortem change. From the original 225 forensic cases examined between 1992 and 2002 in the LAF, a sample of 29 cases were selected from various regions of the Spanish mainland. A data collection protocol was established to reflect factors which the existing specialized literature, documenting the relation existing in the sample analyzed between time since death and the extent of postmortem change, which in the environments examined are distributed into the following phases: Phase 1 (putrefaction): one week to one month on the surface and two months in water. Phase 2 (initial skeletonization): two months on the surface and five to six months in water. Phase 3 (advanced skeltonization): six months to 1.5 years on the surface and 2.5 years buried. Phase 4 (complete skeletonization): about one year on the surface and three years buried. This paper also provide useful information on the impact of carrion insect activity, location, climate, seasonality, and predator.