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Biomedical subjects

J D Gilbert

Publications and source records attributed to J D Gilbert.

At least 73 records · Page 4Linked to original sources
PubMed1989

Health physics measurement of Princeton Tokamaks, 1977-1987.

The Princeton Plasma Physics Laboratory (PPPL) began fusion experiments in 1951. In the early years, the major health physics concerns were associated with x radiation produced by energetic electrons in the plasma. Within the past year, neutron and 3H production from 2H-2H (represented hereafter as D-D) reactions has increased significantly on the larger fusion devices. Tritium retention noted in graphite tiles underscores the significance of material selection in present and future 3H-fueled fusion devices. This paper reports on operational health physics radiation measurements made on various PPPL machines over the past 10 y.

Health Physics↗
PubMed1987

Overabundance of rare-cutting restriction endonuclease sites in the human genome.

A human chromosome 3-specific cosmid library was constructed from a somatic cell hybrid containing human chromosome 3 as its only human component. This library was screened to identify 230 human recombinants which contained an average insert size of 37 kilobases. DNA prepared from 54 of these cosmids, representing 2000 kilobases of human DNA, was then tested for restriction endonuclease sites for EcoRI, HindIII, KpnI, XhoI, and DraI, as well as those of the rare-cutting restriction endonucleases NotI, SfiI, NruI, MluI, SacII, and BssHII. Sites for the latter enzymes were much more abundant than would be expected from theoretical calculations, reflecting non-random clustering of these sites. This has important implications for the use of these enzymes in the construction of physical maps of chromosomes. Some individual cosmids contained large numbers of rare sites, offering an alternative means of physically mapping chromosomes based upon identifying clusters of rare restriction sites. These clusters appear to be spaced an average of 1000 kb apart.

Animals↗
PubMed1984

The pharmacokinetics of meprobamate following its oral and rectal administration as a series of combinations with diphenhydramine, acetylsalicylic acid, codeine and pentaerythritol tetranitrate.

Studies in human volunteers of the pharmacokinetics of the active drugs in the formulations Visano-mini (meprobamate and diphenhydramine HCl), DoloVisano (meprobamate, diphenhydramine HCl, acetylsalicylic acid and codeine phosphate) and VisanoCor (meprobamate, diphenhydramine HCl and pentaerythritol tetranitrate (PETN], have demonstrated systemic absorption of each of the drugs from all of the formulations. Bioequivalence of meprobamate is indicated despite the drug combinations involved. Some differences in diphenhydramine pharmacokinetics are, however, apparent. The bioavailability of meprobamate administered rectally to human volunteers as the marketed preparations DoloVisano Suppositories and Dolo-Visano Suppositories sine codeino, is similar to that observed following oral administration.

Administration, Oral↗
PubMed1982

A study of the plasma levels of pentaerythritol mononitrate following administration of pentaerythritol tetranitrate in combination with meprobamate and diphenhydramine.

The systemic absorption of meprobamate, diphenhydramine and pentaerythritol tetranitrate (PETN) has been demonstrated following oral administration of a formulation containing all three drug substances to human volunteers. A study undertaken in dogs has also been made of the pharmacokinetics of the major nitrated metabolite of PETN when the parent drug is administered with and without meprobamate and diphenhydramine. Pentaerythritol mononitrate shows a six-fold increase in both peak plasma concentrations and area under the 0-12 hour plasma concentration-time curve when PETN is co-administered with a combination of meprobamate, diphenhydramine and nicotinic acid. No such increase is apparent when either meprobamate or diphenhydramine is excluded from the dose. Further increases in pentaerythritol mononitrate plasma levels and AUC 0-12 h are observed when all of the drugs are administered as the formulated coated tablet (VisanoCor).

Adult↗
PubMed1976

Sterols of scallop. Part II. Structure of unknown sterols by combination gas-liquid chromatography and mass spectrometry.

Four sterols, isolated from the scallop Pacopecten magellanicus have been identified as 24-nor-5alpha-cholest-22-en-3beta-ol; 24-norcholest-5-en-3beta-ol; 5alpha-cholest-22-en-3beta-ol; and (E) -24-propylidenecholest-5-en-3beta-ol. These bring to seventeen the total number of sterols identified in this marine mollusc. A fifth newly detected sterol, closely similar in its mass spectrometric properties is 22-cis and trans-cholesta-5, 22-dien-3beta-ol, was clearly distinguished from these by its shorter retention time by GLC.

Animals↗
PubMed1974

The isolation of cholest-5-ene-3beta,26-diol from human brain.

Cholest-5-ene-3beta,26-diol, isolated from human brain, was further characterized by oxidation to 3-oxocholest-4-en-26-ol and to 3-oxocholest-4-en-26-oic acid. Identification was achieved by comparison (by t.l.c., g.l.c. and g.l.c.-mass spectrometry) with corresponding reference compounds derived from kryptogenin.

Brain Chemistry↗