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Biomedical subjects

G Davenport

Publications and source records attributed to G Davenport.

9 recordsLinked to original sources

Isolation and characterization of canine satellite cells.

Satellite cells were isolated from biopsies of the biceps femoris of adult dogs. Virtually all cells expressed muscle-specific proteins. Proliferation of satellite cells increased as the concentration of fetal calf serum (FCS) was increased from 1 to 10% of the basal medium. The addition of mitogenic growth factors resulted in greater proliferation than that of cells cultured in basal medium alone. Maximum proliferation was obtained when fibroblast growth factor-basic (FGF2) was added to the medium, but differences existed between sources or types. Proliferation did not plateau when the concentration of recombinant human FGF2 was 75 ng/ml but reached maximum levels when 50 ng/ml of bovine FGF2 or 10 ng/ml of growth hormone or insulin-like growth factor-1 were added to the medium. Proliferation of satellite cells decreased when more than 5 ng/ml of transforming growth factor-alpha was included in the medium. Exposure of canine satellite cells to chemically defined media induced greater fusion of total nuclei (ODM-34%; 4F, ITT-CF, and SFG-23%) than exposure to other treatments, such as basal medium plus 2 mg/ml of 1-beta-d-arabinofuranosylcytosine, 5% chick embryo extract, 1% horse serum (average 9% fused nuclei), or 1% FCS (2% fused nuclei). Actin, myosin, desmin, neural cell adhesion molecule, MyoD1, and myogenin were expressed by canine satellite cells, but expression of major histocompatibility complex class II antigen was not detected. Reverse transcriptase-polymerase chain reaction detected expression of messenger ribonucleic acid for interleukin-6 (IL-6), IL-15, and leukemia inhibitory factor by canine satellite cells. Collectively, these data suggest that isolated canine satellite cells display properties of other types of myogenic cells and may be useful for further study of the regulation of postnatal myogenesis.

Animals↗

UK CropNet: a collection of databases and bioinformatics resources for crop plant genomics.

The UK Crop Plant Bioinformatics Network (UK CropNet) was established in 1996 in order to harness the extensive work in genome mapping in crop plants in the UK. Since this date we have published five databases from our central UK CropNet WWW site (http://synteny.nott.ac.uk/) with a further three to follow shortly. Our resource facilitates the identification and manipulation of agronomically important genes by laying a foundation for comparative analysis among crop plants and model species. In addition, we have developed a number of software tools that facilitate the visualisation and analysis of our data. Many of our tools are made freely available for use with both crop plant data and with data from other species.

Crops, Agricultural↗

Developmental components of resting ventilation among high- and low-altitude Andean children and adults.

This paper evaluates the age-associated changes of resting ventilation of 115 high- and low-altitude Aymara subjects, of whom 61 were from the rural Aymara village of Ventilla situated at an average altitude of 4,200 m and 54 from the rural village of Caranavi situated at an average altitude of 900 m. Comparison of the age patterns of resting ventilation suggests the following conclusions: 1) the resting ventilation (ml/kg/min) of high-altitude natives is markedly higher than that of low-altitude natives; 2) the age decline of ventilation is similar in both lowlanders and highlanders, but the starting point and therefore the age decline are much higher at high altitude; 3) the resting ventilation that characterizes high-altitude Andean natives is developmentally expressed in the same manner as it is at low altitude; and 4) the resting ventilation (ml/kg/min) of Aymara high-altitude natives is between 40-80% lower than that of Tibetans.

Adaptation, Physiological↗

Helix-coil stability constants for the naturally occurring amino acids in water. 15 Arginine parameters from random poly(hydroxybutylglutamine-co-L-arginine).

Water-soluble copolymers containing L-arginine and N5-(4-hydroxybutyl)-L-glutamine were prepared by copolymerization of the N-carboxy-alpha-amino acid anhydrides of Ndelta-tert-butyloxycarbonyl-L-ornithine and gamma-benzyl L-glutamate, followed by aminolysis with 4-amino-1-butanol, by removal of the tert-butyloxycarbonyl protecting group, and by treatment with O-methylisourea. The copolymers were fractionated and characterized, and the thermally induced helix-coil transitions of these copolymers were studied in water at neutral pH in the presence and in the absence of KCl. The Zimm-Bragg parameters sigma and s for the helix-coil transition in poly(L-arginine) in aqueous solution were deduced from an analysis of the melting curves of the copolymers in the manner described in earlier papers. The computed values of s indicate that L-arginine is a weak helix-making residue at low temperature and a weak helix-breaking residue at high temperature in aqueous solution. The results were found to be in good agreement with those obtained earlier in conformational analyses of arginyl residues in proteins.

Arginine↗