PubMed Health⌕ Search

Biomedical subjects

J Oster

Publications and source records attributed to J Oster.

13 recordsLinked to original sources
PubMed1991

Growth hormone regulation in primary fetal and neonatal rat pituitary cell cultures: the role of thyroid hormone.

GH is first detectable in the fetal rat pituitary between gestational days 18 and 19. The reasons for the GH surge soon after birth and subsequent postnatal decline to adult levels remain unclear. We therefore determined whether GH gene regulation in the developing pituitary could be distinguished from adult rat somatotroph function. In primary cultures of fetal and neonatal rat pituitary cells, GH secretion was detected by the 20th gestational day. These cells were stimulated by GH-releasing hormone (GHRH), but not by T3 or the morphogen retinoic acid. The stimulatory effect of T3 (0.25 mM) on GH secretion was detected only on the 2nd neonatal day and was similar to that seen in mature rat pituitary cell cultures. GHRH (10 nM) treatment for 24 h caused a 5-fold induction of GH secretion in pituitary cells derived from 2-, 5-, and 12-day-old neonatal rats. The presence or absence of T3 in the culture medium did not alter the response to GHRH. In contrast, only 2-fold induction of GH was observed in adult male pituitary cells during the same time course. Insulin-like growth factor-I (IGF-I; 6.5 nM), the peripheral target hormone for GH, resulted in a modest (20%) attenuation of GH secretion from pituitary cells derived from 20-day-old fetuses. IGF-I, however, produced a 70% reduction in GH levels in adult male pituitary cells grown under similar conditions. The effects of IGF-I on adult pituitary cells grown in T3-depleted medium were blunted. Addition of T3 partially restored the responsiveness of these cells to IGF-I. The results suggest that the high circulating GH levels in the fetal and neonatal rat may be secondary to relative insensitivity of the immature somatotroph to the inhibitory actions of IGF-I in addition to enhanced responsiveness to GHRH compared with the adult rat pituitary. Relative thyroid hormone deficiency in the immature rat may be contributory to this early transient state of pituitary IGF-I resistance.

Aging↗
PubMed1976

The G syndrome. A four-generation family study.

A male infant with hypertelorism, hypospadias, swallowing difficulties with tendency to regurgitation and cough, high arched palate, and a delicate voice, consistent with the G syndrome, is reported. In the family the same symptoms in addition to cleft lip and palate were known in several family members through four generations. In the females only slight manifestations of the syndrome were found, and in the males variable expression of symptoms was observed. Autosomal dominant inheritance is likely, but X-linked inheritance cannot be ruled out.

Abnormalities, Multiple↗
PubMed1975

[Anencephalus].

Explore the source record for details and available documents.

Anencephaly↗
PubMed1975

A girl with karyotype 46,XX,del(7)(qter-p 15:).

A girl with partial deletion of the short arms of one chromosome 7 is described. Among many other symptoms she has craniosynostoses. Early closure of cranio-sutures has previously been described in 2 of 3 patients with partial deletion 7. Investigation of a number of genetic marker systems shows that the HL-A, MN, AcP, and GPT loci are not located in the deleted segment.

Adult↗
PubMed1975

Mortality and life-table in Down's syndrome.

The causes of death in 130 patients with Down's Syndrome and mortality rates from a material of 524 patients were tabulated; a life-table for the ages over 5 years was constructed. An overall death rate of 5-7 times the general population rate was found. No sex difference was observed. The excess mortality was expecially high for heart disease and respiratory disease. Also infectious diseases, others than pneumonia and tuberculosis, showed high mortality rates.

Adolescent↗
PubMed1975

A 21-year psycho-social follow-up of 524 unselected cases of down's syndrome and their families.

The death rate was followed, and a life table has been constructed. Three crucial events were examined: 1. the period of diagnosis, 2. the problem of institutionalization versus homecare, 3. the ageing and death of the parents and its consequences for the person with D.S. Several other medical problems, psychological implications and social consequences for the person with D.S., for his parents and siblings are highlighted. The worst problem for parents with the child at home was social isolation; for the parents with the child at an institution it was the very existence of the child. To both groups the most encouraging fact was that their child was happy, friendly and in good spirits. Finally, emphasis is laid upon the medical and paramedical problems which must be discussed and solved to make a harmonious and social life for the person with D.S., for his normal siblings, and for the parents.

Adolescent↗