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Biomedical subjects

J Smith

Publications and source records attributed to J Smith.

At least 955 records · Page 53Linked to original sources
PubMed1989

tRNA-rRNA sequence matches from inter- and intraspecies comparisons suggest common origins for the two RNAs.

1. Comparisons were made of the results of searches within and among different species of organisms for sequence matches between transfer RNAs and ribosomal RNAs. The purpose was to determine whether the matching sequences might result from selection acting on the two RNAs within a common cellular environment. 2. The results indicate that most matches do not reflect such selection. The matches described were more frequent than those found in searches among randomized sequences and the frequency of intraspecific matches was not significantly higher than that of interspecific matches. 3. The matches are thought to identify conserved vestiges of a molecule or molecules ancestral to both classes of RNAs (Bloch, D.P., McArthur, B. and Mirrop, S. (1985). BioSystems, 17: 209-225). The matching sequences are interpreted as homologies.

Anticodon↗
PubMed1989

Quantitation of high molecular weight protein aggregates in opaque and transparent parts from the same human cataractous lens.

Water soluble proteins from clear and opaque parts of the cortex of the same human cataractous lens were analyzed by high pressure liquid chromatography using a TSK 3000 SW gel filtration column. Studies of the 42 different microdissected parts from 7 different lenses demonstrated that the opaque parts possessed a higher percentage of high molecular weight material eluting with the void volume than did the corresponding clear part from the same lens. These results suggest that increased amounts of high molecular weight protein aggregates accompany the process of opacification in the cortex of the human cataractous lens.

Aged↗
PubMed1989

Effect of diet on [lactate]/[pyruvate] ratios during alcohol metabolism in man.

Ten subjects received alcohol by intravenous infusion on two occasions, after five-day periods on high- or low-carbohydrate diets. Blood [lactate]/[pyruvate] ratios were significantly higher during fasting alcohol metabolism after the low-carbohydrate, high-fat diet. The carbohydrate/fat balance in the diet may affect cytoplasmic-mitochondrial NADH transfer. Dietary composition may modify the metabolic changes caused by alcohol.

Adult↗
PubMed1988

AIDS: publications.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Inelastic neutron scattering analysis of picosecond internal protein dynamics. Comparison of harmonic theory with experiment.

The experimental inelastic neutron scattering spectrum of a protein, the bovine pancreatic trypsin inhibitor (BPTI), in a powder sample is presented together with the generalized density of states, G(omega), as a function of the frequency, omega, derived from the scattering data. The experimental results are compared with calculations from two different normal mode analyses of BPTI. One of these, based on an improved model, gives a calculated spectrum and density of states in general agreement with those obtained experimentally; the other, based on an earlier model, shows considerable disagreement. The important improvements in the newer normal mode analysis are the explicit treatment of all atoms (non-polar as well as polar hydrogens are included) and a modified truncation scheme for the long-range electrostatic interactions. The fact that the inelastic neutron scattering measurements can distinguish between the two theoretical models makes clear their utility for the analysis of protein dynamics.

Animals↗
PubMed1988

The structure of the human skin fibroblast collagenase gene.

Genomic clones containing the complete gene encoding human fibroblast interstitial collagenase were isolated from a lambda phage human DNA library. The gene is comprised from 10 exons and spans 8.2 kilobase pairs. We have mapped the relative positions and determined the DNA sequence of all the exon/intron borders of the gene. The organization of the human interstitial collagenase gene is very similar to that of rabbit collagenase and of two other extracellular matrix (ECM) metalloproteases: rat stromelysin (transin) and rat transin 2. All four genes are organized into 10 exons of virtually identical size while the length of the 3' proximal introns is subject to variation. The protein sequence comprising the putative active center is coded for by exon 5 of all four genes and contains a strongly conserved zinc binding site. This observation suggests that the organization of the ECM metalloprotease genes reflect the structure of the functional domains of the enzyme proteins. The structural data accumulated so far provides evidence for the existence of a gene family coding for secreted ECM metalloproteases and suggests that gene duplication played an important role in its formation.

Animals↗
PubMed1988

Pilot trial of branched-chain aminoacids in amyotrophic lateral sclerosis.

22 patients with amyotrophic lateral sclerosis were entered into a double-blind, randomised, placebo-controlled trial of treatment with branched-chain aminoacids. 11 received daily 12 g L-leucine, 8 g L-isoleucine, and 6.4 g L-valine, by mouth, and the remainder received placebo. During the one-year trial, patients in the placebo group showed a linear decline in functional status consistent with the natural history of the disease. Those treated with aminoacids showed significant benefit in terms of maintenance of extremity muscle strength and continued ability to walk.

Amino Acids, Branched-Chain↗
PubMed1988

Direct demonstration of production of transforming growth factor activity by embryonic chick tissue.

The presence of transforming growth factor activity in early chick embryos was directly demonstrated by the ability of limb and tail buds to induce anchorage independent division in NRK 49 f cells. Colony number increased with limb bud number and developmental stage. Medium conditioned by tail buds contained some stimulating effect, and strongly promoted the action of other transforming growth factors.

Animals↗
PubMed1988

Rapid, sensitive detection of plasma IL-1 by extraction and bioassay.

A method for separating IL-1 from plasma inhibitors by silica extraction has been developed and coupled to a highly sensitive bioassay using the LBRM TG6 cell line and the I1-2 dependent HT2A cell line. Using this assay we have detected IL-1 activity in plasma from patients undergoing elective surgery.

Animals↗
PubMed1988

Motor organization of the spinal accessory nerve in the monkey.

The segmental and topographical organization of motoneurons of the spinal accessory nerve was studied in monkeys with horseradish peroxidase (HRP). The sternomastoid muscle is innervated primarily from the C1-C2 level of the cord and the motor column is medial in the ventral horn. The trapezius muscle, however, is innervated primarily from the C2-C3-C4 levels of the cord and the motor column lies in the ventrolateral region of the ventral horn. The data are discussed with regard to treatment of torticollis.

Animals↗