Studies were performed to evaluate the forensic applicability of multiplex amplification of the loci low density lipoprotein receptor, glycophorin A, hemoglobin G gammaglobin, D7S8, and group-specific component (PM loci) and simultaneous typing of these loci using a reverse dot blot approach where allele specific oligonucleotide probes are immobilized on a nylon membrane strip. These results were obtained by using the AmpliType® PM PCR Amplification and Typing Kit. The experiments included: mixed body fluid studies; chemical contaminant effects on the DNA in body fluid samples; the effect of typing DNA from body fluid samples deposited on various substrates; the effect of microorganism contamination on typing DNA derived from blood and semen; the effect of sunlight and storage conditions on DNA typing; determination of the sensitivity of detection of the PM test kit; determination of cross-reactivity of DNA from species other than human; typing DNA derived from various tissues from an individual; and an evaluation of the hybridization temperature of the assay. The data demonstrate that DNA exposed to a variety of environmental insults yields reliable PM typing results. Allele and genotype frequencies for six loci (PM loci and HLA-DQα) were determined in African Americans, Caucasians, southeastern Hispanics, and southwestern Hispanics. All loci meet Hardy-Weinberg expectations and there is little evidence for association of alleles between the loci. The frequency data can be used in forensic analyses and paternity tests to estimate the frequency of a multiple locus DNA profile in various general United States populations.

The antioxidant capacities of alpha- and gamma-tocopherols (alpha-E and gamma-E) and their quinones (alpha-EQ and gamma-EQ) were determined in non-biological and biological systems. The non-biological system consisted of arachidonic acid [20:4 (n-6)], the oxidant cumene hydroperoxide, and a Fe3+ catalyst to facilitate malondialdehyde (MDA) formation from lipid peroxides. alpha-E and gamma-E had similar antioxidant capacities in this system. alpha-EQ also functioned as an antioxidant, while gamma-EQ exhibited a crossover effect by functioning as an antioxidant at low concentrations and a prooxidant at high concentrations. Biological lipid peroxidation in smooth muscle cells challenged with 20:4 (n-6) was measured both by MDA formation in confluent cultures and by cell growth in proliferating cultures. alpha-E, gamma-E and alpha-EQ had similar antioxidant capacities, but gamma-EQ was highly cytotoxic for cells in both confluent and proliferating cultures. Cellular retention of antioxidants was estimated indirectly from MDA formation when cells were loaded with an antioxidant (preincubation) and then incubated for varying periods of time in fresh media containing 20:4 (n-6). Cellular retention also was measured directly with tritiated alpha-E and tritiated alpha-EQ. These studies showed that cellular retention decreased in the sequence gamma-E greater than alpha-E greater than alpha-EQ. Thus, cellular retention does not explain the enhanced antioxidant capacity of alpha-E compared to gamma-E that has been reported for animal systems. The antioxidant capacity of alpha-E evidently is enhanced by its metabolism to a quinone which, unlike the quinone from gamma-E, functions as a biological antioxidant.

The polymerase chain reaction (PCR) was used to amplify the HLA DQα gene using DNA recovered from evidentiary samples. Amplified HLA DQα DNA was then typed using sequence-specific oligonucleotide probes. Slight modifications of previously published DNA extraction methods improved typing success of bloodstains and semen-containing material. Evidentiary samples, consisting of 206 known bloodstains, 26 questioned bloodstains, and 123 questioned semen-containing evidentiary materials were analyzed from 96 cases previously analyzed by restriction fragment length polymorphism (RFLP) typing in the FBI Laboratory. Of the known bloodstains, 98.5% yielded DQα typing results. Of the questioned samples, 102 of 149 (24/26 bloodstains and 78/123 semen-containing materials), or 68%, produced typing results. Of the 78 cases that were RFLP inclusions, 59 yielded interpretable DQα results and these were all inclusions. The remaining 19 cases could not be interpreted for DQα. Of the 18 RFLP exclusions, eleven were DQα exclusions, four were DQα inclusions, and three could not be interpreted for DQα. It is expected that because of the difference in discrimination potential of the two methods, some RFLP exclusions would be DQα inclusions. Some samples that failed to produce typing results may have had insufficient DNA for analysis. Employment of a human DNA quantification method in DQα casework would allow the user to more consistently use sufficient quantities of DNA for amplification. It also could provide a guide for determining if an inhibitor of PCR is present, thus suggesting the use of a procedure to improve amplification. This study provides support that the HLA DQα typing procedure is valid for typing forensic samples.

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Primary cultures of smooth muscle cells were established from the medial layer of guinea pig aorta. Confluent cells at passage level 4-6 were challenged with arachidonic acid and treated with a number of antioxidants and inhibitors of specific lipid peroxidation pathways. Lipid peroxidation was measured by the thiobarbituric acid test for malondialdehyde (MDA) and the isolation of hydroperoxy fatty acids (HPETE) by high performance liquid chromatography (HPLC). Prostanoids were measured by radioimmunoassay and the separation of labeled compounds by HPLC. MDA, 6-keto-PGF1 alpha, and PGE2 were formed when cells were challenged with arachidonic acid and these cells synthesized small amounts of one HPETE isomer, 15-HPETE. The HPETE isomers characteristic of the lipoxygenase pathway, 12-HPETE and 5-HPETE, were not detected. Furthermore, the lipoxygenase inhibitors, eicosatetraynoic acid (ETYA) and 6,7-dihydroxycoumarin (Esculetin), did not block MDA formation. These data show that MDA is not generated in the cells by a lipoxygenase pathway. The cyclooxygenase inhibitors, indomethacin and ETYA, did not block MDA formation but these agents blocked the formation of 15-HPETE. These data show both that 15-HPETE is generated by a cooxidation pathway and that 15-HPETE and cooxidation are not involved in MDA formation. Three inhibitors of cytochrome P450 linked lipid peroxidation, 2-amino-3-ethoxycarbonyl-6-benzyl-4, 5,6,7-tetrahydrothieno-[2,3-C]-pyridine (Tinoridine), 3-methyl-1,2-di-3-pyridyl-1-propanone (Metyrapone) and phenobarbital, did not block MDA formation. These data support earlier studies that indicated that MDA is not generated by a P450 pathway. Cells contained a bound precursor that decomposed to MDA when cells were treated with Fe3+. The cells exhibited autofluorescence and concentric lamellae in lipid droplets that are characteristic of ceroid-lipofuscin. These observations are consistent with lipid peroxidation through increased peroxisomal activity leading to the generation of MDA and the accumulation of ceroid-lipofuscin. The natural antioxidants, vitamin E and vitamin E quinone (EQ), and the synthetic antioxidants, butylated hydroxytoluene and nordihydroguaiaretic acid (NDGA), alpha-naphthol (alpha-N) and propyl gallate (PrGa), all blocked MDA formation in confluent smooth muscle cells, showing that these antioxidants did not function solely as specific inhibitors of lipoxygenase, cooxidation or P450 pathways. Cell proliferation was measured in cells challenged with arachidonic acid and treated with antioxidants and other inhibitors. The least cytotoxic and most potent antioxidant, EQ, blocked MDA formation in confluent cells and promoted grow