PubMed Health⌕ Search

Biomedical subjects

R F Shaw

Publications and source records attributed to R F Shaw.

At least 19 recordsLinked to original sources
PubMed1989

Cocaine- and methamphetamine-related deaths in San Diego County (1987): homicides and accidental overdoses.

Cocaine- and methamphetamine-related homicides and fatal accidental overdoses in San Diego County were studied retrospectively for the 1987 calendar year. Cocaine was involved in 66 cases (39 homicides, 27 accidental overdoses), methamphetamine in 32 cases (23 homicides, 9 accidental overdoses), and a combination of cocaine and methamphetamine in 10 cases (4 homicides, 6 accidental overdoses). The composite for cocaine-related deaths was a 30-year-old black man in whom was also found at least 1 other drug, usually ethanol or morphine. The composite for methamphetamine-related deaths was a 32-year-old Caucasian man who used methamphetamine with at least 1 other drug (usually ethanol). For cases involving both cocaine and methamphetamine, the composite was a 36-year-old Caucasian man in whom was also found at least 1 other drug, usually ethanol, codeine, or morphine. Mean tissue concentrations of cocaine and benzoylecgonine were significantly higher in accidental overdoses than in homicides except for cocaine concentrations in liver, which did not differ significantly between the two groups. For methamphetamine-related deaths there was no significant difference between mean tissue concentrations in accidental overdoses and in homicides. Cocaine or methamphetamine or both were involved in approximately one third of homicides in San Diego County in 1987, and when fatal accidental overdoses were included, cocaine was involved in twice as many cases as methamphetamine.

Accidents↗
PubMed1987

A fatal poisoning from Nicotiana glauca.

A young adult male was found dead in a field. No cause of death was apparent at autopsy, and the only positive toxicological finding was the presence of a nicotine-like alkaloid isolated from the liver. Anabasine, the major, highly toxic alkaloid of the shrub, Nicotiana glauca (tree tobacco) was subsequently identified in all body specimens examined using gas chromatography/mass spectrometry. Concentrations of anabasine in blood, urine and other body organs are reported.

Adult↗
PubMed1985

Effect of sodium fluoride on cholinesterase activity in postmortem blood.

Thirty-two postmortem blood specimens, with and without sodium fluoride as preservative, were analyzed for cholinesterase activity by the Michel method. The fluoridated specimens, which contained from 0.7 to 31 mg/mL (average 6.3) of sodium fluoride, were found to exhibit cholinesterase activities that were 5 to 59% (average 25%) lower than the duplicate unfluoridated specimens. We concluded that, while this decrease is quite significant, a fluoridated postmortem blood specimen may be used for the measurement of cholinesterase activity when a non-fluoridated specimen is unavailable.

Acetylcholinesterase↗
PubMed1977

Hemoglobin and the genetic code. Evolution of protection against somatic mutation.

One-half of the twenty amino acids of the genetic code are just one mutational step away from the chain-terminator codons UAA, UAG, and UGA. It is postulated that somatic mutation to terminator is a hazard to which the organism has and to respond by adjusting certain proteins in the direction of fewer mutable residues. This view is supported by calculations based on the primary structure of five of the human hemoglobin chains. Each chain is scored for mutability to terminator in accord with the numbers and kinds of amino acids present. Among the adult chains, the most essential one, the alpha, has lowest mutability. The beta and delta follow, and in order of the presumed harm to the organism of a shortage of chain copies. Ante-natal chains tend to have higher mutabilities, supporting the view that cumulative mutational change in DNA can do little if the gene ceases to transcribe early in life. Two other predicitons based on the supposition of effective selection against mutability to terminator are also met: chain length of polypeptides is negatively correlated with their scores for mutability to terminator, and examination of the recently determined sequence of beta messenger RNA shows preferential use of codons that are not readily mutable to terminator.

Amino Acid Sequence↗
PubMed1977

Cocaine-related death.

Cocaine use and abuse, an ancient custom, is once again commonplace. While severe toxicity appears to be rare, overt poisoning including death can occur. This report documents nine cases of death associated with cocaine use; in three of these cocaine appears to be causative. Toxicologic analysis of body fluids and tissues was affirmative and levels are reported. Cocaine should be considered in serious drug overdose-reactions, especially after illicit injection.

Adolescent↗
PubMed1976

Population genetics of Alport's syndrome. Hypothesis of abnormal segregation and the necessary existence of mutation.

The diagnosis of Alport's syndrome is generally not considered in the absence of a positive family history. Family studies indicate that transmission occures by a rare autosomal dominant gene. The deviation of transmission ratios from the classical Mendelian pattern is best explained by abnormal segregation. Based on observed pedigree data, calculations were made of the expected equilibrium population frequency of Alport's syndrome assuming mutation rates of zero, 10, and 50 per million gametes. Zero mutation rate should result in disappearance of the Alport gene. An equilibrium frequency corresponding to that actually observed in Rhode Island implies a mutation rate of 10 per million gametes. Furthermore, up to 18% of all newborns with the Alport genotype may represent new mutants. Thus, isolated cases of Alport's syndrome may occur in the absence of other affected family members.

Female↗
PubMed1975

Comparison of results for quantitative determination of morphine by radioimmunoassay, enzyme immunoassay, and spectrofluorometry.

The quantitative results (accuracy and precision) for determination of opiates by radioimmunoassay (RIA), enzyme immunoassay (EMIT), and spectrofluorometry on split samples are compared. A variety of physiological samples were studied, including random urine from a methadone maintenance clinic and postmortem urine, blood, bile, brain, and lung tissue from heroin-induced or heroin-related deaths. The opiate concentrations detected by the two immunoassay methods were in good agreement with each other in the absence of interfering substances which are believed to react with the antimorphine antibodies. The immunoassay results were in agreement within the relative standard deviation with the fluorometry results in 55% of the urine samples and 80% of the blood samples. The immunological methods are superior to fluorometry for quantitation of morphine in urine samples due to quenching interferences in fluorometry from urine. They were comparable to fluorometry for quantitation of morphine in blood samples.

Adult↗
PubMedDate not supplied

MS processing.

Explore the source record for details and available documents.

Manuscripts as Topic↗
PubMedDate not supplied

Ethchlorvynol ingestion in San Diego County: a 14-year review of cases with blood concentrations and findings.

Cases of nonfatal (51) and fatal (38) ingestions involving ethchlorvynol over a 14-year period (1975 through 1988) were reviewed in order to evaluate the current status of ingestion of this drug. In both series of cases men and women were involved approximately equally. Sixty-three percent of cases in both series occurred during the period 1975 through 1980. Most (78% of nonfatal and 89% of fatal) ingestions involved other drugs in addition to ethchlorvynol. Physical findings for nonfatal ingestions and causes of death for fatal ingestions are presented. Blood ethchlorvynol concentrations are discussed, and a composite of the average patient for each series is presented. Although ethchlorvynol abuse appears to be decreasing with time, it still occurs, and a search for this sedative-hypnotic agent should be included in the so-called "toxicology screen."

Adolescent↗
PubMedDate not supplied

The question of natural selection against mutable-to-terminator codons.

Codons that differ from a terminator triplet by only a single base are sometimes thought, because of their greater risk of undergoing a harmful mutation, to be kept at a reduced frequency by natural selection. The present study on human genes shows that these codons are infrequent, but their low frequency is not directly related to their risk of mutation to terminator. Rather, it is a consequence of their ending in A or G; comparable A-ending and G-ending codons that are not mutable to terminator are also infrequent. Natural selection does not appear to have depressed the frequency of mutable-to-terminator codons by directly eliminating some of them individually. It may have depressed their frequency indirectly by adjusting mutation rates in the population so that most of the purine-ending codons--and consequently most of the mutable-to-terminator ones as well--are infrequent.

Adenosine↗