Biomedical subjects

A Zarate

Publications and source records attributed to A Zarate.

At least 37 records · Page 2Linked to original sources

PubMed1976

Long-acting luteinizing homone-releasing hormone (LH-RH) analogs in the treatment of female infertility.

Induction of ovulation in 20 infertile women was attempted by the use of two synthetic analogs of LH-RH, D-ALA6-Des-Gly10-ethylamide and D-Leu6-Des-Gly10-ethylamide. Ovulation was obtained in five out of the 16 in whom D-Leu6-Des-Gly10-LH-RH ethylamide was administered intramuscularly. Two of the five women received the LH-RH analog additioned of polysaturated gelatines as carrier medium. None of these women got pregnant. It is concluded that better therapeutic results might be expected when a suitable LH-RH vehicle allowing a gradual release of LH-RH analog is obtained.

Adolescent↗

PubMed1976

Clinical use of the LH-RH in assessing gonadotropic reserve in children with idiopathic precocious puberty, premature thelarche and premature adrenarche.

Serum LH and FSH were assayed in 31 girls with normal pre puberty, precocious puberty, premature thelarche, and premature adrenarche, aged 2 to 9 years. The effect of synthetic luteinizing hormone-releasing hormone (LH-RH) on serum gonadotropins was evaluated in eleven of them. In all girls with precocious puberty, serum LH was increased up to high levels. The mean releasable LH in two girls with idiopathic precocious puberty was significantly greater than in normal prepubertal or pubertal children. Basal FSH in children with precocious puberty was within the limits of normal prepuberal children, and FSH secretion in response to LH-RH was not significantly greater than in the group of normal prepubertal and pubertal girls. In children with premature thelarche and premature adrenarche, basal levels of LH and FSH, as well as gonadotropin response to LH-RH were in the prepubertal range. These preliminary results show that the LH-RH test might be of clinical value in differenitating abnormal puberal development.

Age Factors↗

PubMed1976

[Secretion of prolactin in normal anencephalic newborn infants].

Serum prolactin (PRL) was measured by radioimmunoassay in pregnant women at term and in newborns. In 38 newborns of gestational age 39--40 weeks, concentration of PRL in umbilical venous blood was 280.8 +/- 11.2 ng/ml; in maternal venous blood, concentration of PRL was 347.0 +/- 20.1 ng/ml. In the newborn it was found a significant difference in PRL values between both sexes (p less than 0.05), being higher in males than in females (290.0 +/- 14.6 vs. 260.0 +/- 17.1 ng/ml). In three anencephalic infants, PRL ranged from 92.6 to 369.0 ng/ml; 400 mug of thyrotropin-releasing hormone (TRH) administered as bolus injection evoked a rise in PRL in two out of the three, while synthetic luteinizing hormone releasing hormone (LH-RH) elicited no response of FSH secretion. These observations in the fetus and anencephalic infants confirm that the fetus produces high levels of PRL and that this function is independent of any hypothalamic control. The high levels of gestational estrogens seem to be the direct stimulus on the lactotropes to induce synthesis and secretion of PRL. The role of PRL during gestation has not been elucidated.

Anencephaly↗

PubMed1975

Geophagia. A cause of life-threatening hyperkalemia in patients with chronic renal failure.

Geophagia has been associated with life-threatening hyperkalemia in five patients with chronic renal failure. All five patients were black and had been born in the southeastern United States. Four had had frequent hyperkalemia requiring at least one hospitalization, and two had had hyperkalemia with serum potassium concentration as high as 9.8 mEq/liter, resulting in cardiac arrest in one and paralysis, disorientation, and cardiac arrythmia in the other. Since riverbed clay contains as much as 100 mEq of potassium in 100 gm of clay, much of which is exchangeable at acid pH, the mechanism of geophagia-induced hyperkalemia appears to be the absorption of potassium released from clay after ingestion. After discontinuing geophagia, no new hyperkalemic episodes occurred in these patients.

Adult↗

PubMed1975

Increased and prolonged LH-RH/FSH-RH activity of synthetic (D-Ala6, Des-Gly-NH210)-LH-RH-ethylamide in normal women.

A synthetic LH-RH analogue (D-Ala6, Des-Gly-NH210)-LH-RH ethylamide exhibited an increased and prolonged LH-RH/FSH-RH activity in normal women. The integrated amounts of LH and FSH levels for this LH-RH analogue were about nine and five times greater than for the same doses of synthetic LH-RH. It is expected that this synthetic LH-RH analogue might yield more positive results than with LH-RH when used in infertility problems.

Adolescent↗

PubMed1975

Pituitary hormonal reserve in patients presenting hyperprolactinemia, intrasellar masses, and amenorrhea without galactorrhea.

The pituitary release of gonadotropins, prolactin, and TSH after the simultaneous intravenous administration of 50 mug LH-RH was 400 mug TRH was evaluated in 7 amenorrheic women with sellar enlargement and hyperprolactinemia. It was found that only minimal amounts of LH and FSH were released by LH-RH. All patients had elevated serum prolactin levels but TRH administration elicited negligible release of prolactin. This was in contrast to the normal TSH response to TRH in most of these women. It is concluded that intrasellar masses may be associated with hyperprolactinemia which does not necessarily cause galactorrhea and that impaired gonadotropin reserve correlates with the presence of amenorrhea.

Adult↗

PubMed1974