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Biomedical subjects

C Castillo

Publications and source records attributed to C Castillo.

At least 145 records · Page 8Linked to original sources
PubMed1987

Expression, inheritance, and linkage relationships among eight enzyme genes in Dermacentor albipictus (Packard) (Acarina: Ixodidae).

Starch gel electrophoresis was used to examine the inheritance, expression, and linkage relationships among eight enzyme genes in the winter tick, Dermacentor albipictus. A fructose-specific hexokinase (FHK), adenylate kinase (ADK), and two forms of aconitase (ACON-A, ACON-C) appeared to have monomeric quaternary structures. A glycylleucine peptidase (PEP), isocitrate dehydrogenase (IDH), and anodally migrating malate dehydrogenase (MDH-A) were apparently dimers. The quaternary structure of glucose phosphate isomerase (GPI) could not be determined because of the similarity in relative mobility of the two available electromorphs. The genes for GPI, FHK, and ADK are located on the X chromosome in the following order: Adk - 37.4 - Gpi - 24.6 - Fhk, with Adk - Fhk being 46.5 map units apart. The remaining five genes were autosomally inherited. Of the 10 possible paired combinations of these genes, only the data for two pairs, Idh-Mdh (44.5% recombinants) and Acon-A--Acon-C (46.4% recombinants), suggested statistically significant linkage.

Animals↗
PubMed1986

An auxiliary protein for DNA polymerase-delta from fetal calf thymus.

An auxiliary protein which affects the ability of calf thymus DNA polymerase-delta to utilize template/primers containing long stretches of single-stranded template has been purified to homogeneity from the same tissue. The auxiliary protein coelutes with DNA polymerase-delta on DEAE-cellulose and phenyl-agarose chromatography but is separated from the polymerase on phosphocellulose chromatography. The physical and functional properties of the auxiliary protein strongly resemble those of the beta subunit of Escherichia coli DNA polymerase III holoenzyme. A molecular weight of 75,000 has been calculated from a sedimentation coefficient of 5.0 s and a Stokes radius of 36.5 A. A single band of 37,000 daltons is seen on sodium dodecyl sulfate gel electrophoresis, suggesting that the protein exists as a dimer of identical subunits. The purified protein has no detectable DNA polymerase, primase, ATPase, or nuclease activity. The ability of DNA polymerase-delta to replicate gapped duplex DNA is relatively unaffected by the presence of the auxiliary protein, however, it is required to replicate templates with low primer/template ratios, e.g. poly(dA)/oligo(dT) (20:1), primed M13 DNA, and denatured calf thymus DNA. The auxiliary protein is specific for DNA polymerase-delta; it has no effect on the activity of calf thymus DNA polymerase-alpha or the Klenow fragment of E. coli DNA polymerase I with primed homopolymer templates. Although the auxiliary protein does not bind to either single-stranded or double-stranded DNA, it does increase the binding of DNA polymerase-delta to poly(dA)/oligo(dT), suggesting that the auxiliary protein interacts with the polymerase in the presence of template/primer, stabilizing the polymerase-template/primer complex.

Animals↗
PubMed1978

Protein digestion and jejunal dipeptidase activity in rats fed a normal protein alcohol diet during 6 months.

Protein digestion was studied in pair-fed rats receiving an adequate (protein 12% and alcohol 35% of calories) diet during 24 weeks. No differences in fecal nitrogen excretion were observed between the alcohol-treated and control rats. At the 24th week the rats were sacrificed and jejunal mucosa dipeptidase activity was studied. No differences were found either between controls and alcohol-treated animals.

Animals↗
PubMed1976

Fine structure of the small intestinal mucosa in infantile marasmic malnutrition.

The jejunal mucosa was studied in infantile marasmic malnutrition in the early phase after treatment was begun and before the onset of significant weight gain. In 7 infants light microscopy before recovery showed that the mucosa was normal or mildly abnormal in 4, and moderately abnormal in 3 cases. The electron microscope disclosed abnormalities of the brush border, large autophagosomes and residual bodies, and the deposition of collagen, filaments, and a dense, finely granular material below the basal lamella. Three of the infants were studied again during recovery. Although the histology remained unchanged, electron microscopy revealed improvement of the brush border, disappearance of the autophagosomes, and smaller and fewer residual bodies. The dense material below the basal lamella was absent whereas the fibrillar components remained. It is postulated that the fine structural lesions observed may be due to the derangements in cell metabolism caused by the severe, prolonged restriction of protein and caloric intake.

Cell Membrane↗