What is medical ethics consultation?

What happens when the field of ethics consultation meets the hermeneutics of suspicion.     

Post-injection hybridization of complementary DNA strands on capillary electrophoresis platforms: A novel solution for dsDNA artifacts

Several laboratories have reported the occurrence of a split or n − 1 peak at the vWA locus in PowerPlex^® 16 and PowerPlex^® ES amplification products separated on 4- and 16-capillary electrophoresis instruments. The root cause of this artifact is post-PCR reannealing of the unlabeled, unincorporated vWA primer to the 3′-end of the tetramethylrhodamine (TMR)-labeled strand of the vWA amplicon. This reannealing occurs in the capillary post-electrokinetic injection. The split peak is eliminated by incorporation into the loading cocktail of a sacrificial hybridization sequence (SHS) oligonucleotide that is complementary to the vWA primer. The SHS preferentially anneals to the primer instead of the TMR-labeled strand of the vWA amplicon. In addition, the n − 10/n − 18 artifact that may be seen at the vWA locus was determined to be due to double-stranded amplicon formed post-electrokinetic injection into the capillary. This was also eliminated by adding in two Complementary Oligo Targets (COT1 and COT2) in addition to the SHS oligonucleotide into the loading cocktail. These three oligonucleotides are complementary to the 33 bases at the 5′-end of the unlabeled vWA amplicon strand and the 60 bases at its 3′-end and therefore compete for hybridization to the TMR-labeled amplicon strand. Incorporation of these three oligonucleotides in the Internal Lane Standard 600 (ILS600) eliminate both the split peak and n − 10/n − 18 artifact in PowerPlex^® 16 and PowerPlex^® ES amplification products without affecting sizing of alleles at the vWA locus or any locus in the PowerPlex^® 16, PowerPlex^® Y, PowerPlex^® ES, AmpFlSTR^® Profiler Plus^® ID, AmpFlSTR^® Cofiler^®, and AmpFlSTR^® SGM Plus^® kits.     

Blood group frequencies of the population of Trinidad and Tobago, West Indies.

The results of grouping tests performed on blood samples collected over a five-year period at the Trinidad and Tobago Forensic Science Centre are presented. The samples were tested using the ABO, PGM, EAP and GLO blood group systems. Phenotypic frequencies and allele frequencies for each system were calculated for the two major ethnic groups of the population, the African and East Indian. Matching probabilities, which can be used in the interpretation of physical evidence in forensic cases, were also calculated.     

PROSTITUTION,IV DRUG USE,AND SEXFOR-CRACK EXCHANGES AMONG SERIOUS DELINQUENTS: RISKS FOR HIV INFECTION*

There is mounting evidence that HIV infection among adolescents is increasing, particularly among minorities and inner-city youths involved in certain high-risk activities, such as multiple sex partners and intravenous drug use. Interviews conducted “on the street” with 611 seriously delinquent male and female adolescents (ages 12–17) included questions about their involvement in prostitution, intravenous drug use, and sex-for-crack exchanges. Findings included high percentages of youths engaged in these HIV-risk activities and a consistent association between all of them and greater illicit drug use. This would suggest that these risk behaviors may be surprisingly prevalent among some inner-city adolescent groups. Special AIDS prevention/intervention targeting these groups is warranted and urgently needed. Drug treatment should be a central focus of such programs.     

Application of a simple extraction procedure using aqueous ammonia to the analysis of basic drugs in blood by gas chromatography

A simple and reliable previously reported extraction procedure has been extended to the analysis of a wide range of basic and neutral drugs in postmortem blood and other tissues. The method employs 200 microliters of blood treated with water and ammonia and extracted with diethyl ether. The concentrated extract is generally sufficiently clean for direct analysis by gas chromatography and high pressure liquid chromatography. Recovery, precision and linearity data are presented for selected drugs.