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Biomedical subjects

S M Guo

Publications and source records attributed to S M Guo.

24 records · Page 2Linked to original sources
PubMed1980

Radioimmunoassay for mouse nerve growth factor (NGF). Effects of thyroxine administration on tissue NGF levels.

A sensitive and specific radioimmunoassay (RIA) has been developed for beta-nerve growth factor (NGF) purified from the submaxillary gland of the adult male mouse. The RIA is sensitive to 13 pg/assay tube with an intra-assay coefficient of variation of 7% and an interassay coefficient of variation of 11.8%. Of the substances tested for immunological cross-reactivity in the RIA, only mouse epidermal growth factor caused significant displacement of the radiolabeled ligand; 11% at a dose of 10 microgram/ml. Mouse tissue extracts diluted out parallel to the standard curve. The effects of altered thyroid function on tissue NGF concentration in adult male mice were studied using the RIA. Thyroxine administration (25 microgram T4 i.p. daily for 12 days) caused significant increases in submaxilllary gland and liver NGF content and concentration (P less than 0.001) compared to controls but had no significant effect on heart and kidney NGF levels. Propylthiouracil treatment (0.05% PTU in the drinking water for 21 days) led to a marked increase in thyroid gland weight (550% of control) but had no significant effect on NGF concentration in any of the organs studied with the exception of kidney where a 75% reduction in NGF concentration was observed. These studies indicate that thyroid hormones increase NGF content and concentration in the submaxillary gland and liver of adult male mice and are suggestive of increased NGF synthesis. Thyroid hormones may therefore play an important regulatory role in NGF metabolism in peripheral tissues of the adult mouse.

Animals↗
PubMed1979

Thyroxine increases nerve growth factor concentration in adult mouse brain.

The effects of thyroxine and propylthiouracil on nerve growth factor concentrations in cerebral cortex, cerebellum, and brainstem of adult male mice were assessed by using a sensitive radioimmunoassay for the beta-subunit of mouse nerve growth factor. Thyroxine administration significantly increased the concentration of nerve growth factor in all three brain areas compared to control values, whereas propylthiouracil was without effect. These results suggest that thyroid hormones stimulate nerve growth factor synthesis in the mature central nervous system, and raise the possibility that the influence of thyroid hormones on central nervous system development might be mediated or influenced by nerve growth factor.

Animals↗
PubMedDate not supplied

Monthly growth status from a longitudinal study of Canadian infants.

Reference data for weight, recumbent length and head circumference at 1-month intervals from 1 through 18 months have been developed from measurements of 351 healthy infants born at term in Montreal or Toronto. Each infant was measured serially from 1 to 18 months. A 3-parameter mathematical model was fitted to the serial data for each infant. The model fitted the serial data well for almost all the infants as evaluated by the residual mean square errors. Subsequently, values were estimated for each month of age from 1 through 18 months for each infant. These estimated values allowed the development of reference data that have been presented in tables and in graphs.

Adult↗