Determination of cocaine and benzoylecgonine in human amniotic fluid using high flow solid-phase extraction columns and HPLC.

A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.     

Polymerase chain reaction (PCR) amplification and human leukocyte antigen (HLA)-DQ alpha oligonucleotide typing on biological evidence samples: casework experience.

The polymerase chain reaction (PCR) method of specific gene amplification was used in casework to synthesize millions of copies of the polymorphic second exon of the human leukocyte antigen (HLA)-DQ alpha (or DQA1) locus from a variety of evidence samples. The HLA-DQ alpha allelic variants in the amplified deoxyribonucleic acid (DNA) were determined in a rapid non-radioactive test by hybridization to sequence-specific oligonucleotide probes in both the dot-blot and reverse dot-blot formats. This genetic typing system has been subjected to blind proficiency testing; the performance of this test in the analysis of experimentally mixed samples was also evaluated. As of August 1990, over 250 cases have been tested and more than 2000 individual evidence (bloodstains, semen stains, individual hairs, bone fragments, and tissue sections) and reference samples have been analyzed. The first 198 of these cases are summarized in this paper; in 65% of the cases with conclusive results a suspect was included, and in 35%, all suspects were excluded. Individual cases as well as some of the general issues relating to forensic science analysis and this genetic typing system are discussed. The high rate of exclusion reported here combined with the ability of PCR to type old evidence samples suggests the relevance of this genetic test for postconviction review; two cases in which the convicted suspect was excluded are discussed.     

An improved method for complement subcomponent C1R typing

An improved method has been developed for the reliable classification of different C1R genetic variant forms from human serum or plasma. The method combines the use of neuraminidase-digested samples followed by monodimensional isoelectric focusing in the pH range 5 to 8 followed by immunoblotting. The method yields a simple pattern, with one major band in homozygote and two major bands in heterozygote cases.     

Finding audiences, changing beliefs: the structure of research use in Canadian health policy

The impact of research information depends on its ability to change beliefs or policy assumptions within the relevant audiences. As a hybrid of American and British systems, Canada's chosen decision-making structure for policy-making and its legislative framework for health insurance make these audiences unclear and not readily accessible. This factor and historical characteristics of the research community which made them only partially responsive to the values of decisionmakers provide an explanation for the limited past use of research information in Canadian health policy. More recently, improved responsiveness by researchers and an emerging definition of the audiences by legislative policymakers are bringing about a gradual increase in the potential impact of research at the levels of administrative and clinical policy. Because of continuing decision-making constraints on legislative policy, however, impact at this level is predicted to remain diffuse, with only cautious acceptance of the changes in beliefs implied by research.     

The Olson ratio and indirectly endogenous rent

Public Choice - We consider an economy where the rent value depends indirectly on value-adding investment of agents (thus indirectly endogenous) and the win-probability is a function of rent...