Search PubMedSearch

Biomedical subjects

J K Townsend

Publications and source records attributed to J K Townsend.

4 recordsLinked to original sources

Mother and daughter perceptions of their relationship: the influence of adolescent pregnancy status.

This investigation focused on the perceived relationships between 95 mothers and their adolescent daughters. It sought to determine if there was a significant difference in the mother-daughter relationship as perceived by pregnant versus nonpregnant adolescents, and whether the mothers of these two groups, when compared to each other, differed in their feelings for their daughters. In contrast to other investigations, no striking differences between the groups in intimacy, attachment, and strength of feeling as indicated by a questionnaire were found, though results were generally in the predicted direction. Nevertheless, a strong correlation between daughters' and mothers' answers was found, indicating an overall positive perception by both toward their relationship.

Adolescent

Bioautographic visualization of dihydrofolate reductase in enzyme overproducing BHK mutants.

A bioautographic procedure has been developed for the visualization of the isozymes of dihydrofolate reductase (DHFR, E.C. 1.5.1.3). In addition to detecting electrophoretically separated enzymes, bioautography was utilized to visualize DHFR after isoelectric focusing on polyacrylamide gels. Both zone electrophoresis and isoelectric focusing were used to compare wildtype BHK cells to mutants which overproduce dihydrofolate reductase. In agreement with other physical data, the BHK-A5 overproduction mutant appears to produce more dihydrofolate reductase of the same electrophoretic mobility and isoelectric point as wild type cells.

Animals

Characterization of naturally occurring auxotrophic mammalian cells.

In a previous study, several cultured cell lines were detected which are naturally occurring auxotrophs. In this investigation, the enzyme deficienceis involved are described. It is demonstrated that the Chinese hamster cell lines CHO(K1), YH21, RJK-36, and CHW-1102 are deficient in cystathionase and argininosuccinate synthetase. In addition, CHO (K1) and CHW-1102 were found to lack argininosuccinate lyase. CHW-1102 cells were also found to be unable to proliferate in medium containing branched-chain alpha-keto acids in place of the corresponding L-amino acids since CHW-1102 cells lack branched-chain aminotransferase.

Amino Acid Isomerases