PubMed Health⌕ Search

Biomedical subjects

M E Escobar

Publications and source records attributed to M E Escobar.

24 records · Page 2Linked to original sources
PubMed1987

Hormonal profile in pubertal females with chronic renal failure: before and under haemodialysis and after renal transplantation.

The effects of chronic renal failure on the hypothalamic-pituitary-ovarian axis in 25 girls, aged 9.1 to 20.9 years (mean 13.8) were studied. Twelve patients on conservative treatment (group A) had serum creatinine values between 176.8 and 1502.8 mumol/l; 9 patients were on haemodialysis (group B); and 12 patients had received a renal transplant (group C). Tanner stage of breast development was delayed relative to chronological age in 5 out of 18 patients. Serum oestradiol was normal or low when related to pubertal stages in all groups. Serum LH was elevated in group A and B patients, but normal in group C patients. Serum FSH was elevated in 6 out of the 21 patients in group A plus B, and in 2 out of the 12 patients in group C. Serum PRL was elevated in 12/12, 6/8, and 4/11 patients in group A, B, and C respectively. After GnRH administration to 4 patients in group A, 3 showed delayed or absent gonadotropin response; all 4 patients studied in group C showed normal gonadotropin response. The data indicate a decreased E2 secretion, abnormal gonadotropin and PRL levels and a blunted gonadotropin response to GnRH in girls with chronic renal failure. These results seem to indicate an alteration of the hypothalamic-pituitary unit that can be reversed after successful renal transplantation.

Adolescent↗
PubMed1982

Inhibition of follicle-stimulating hormone receptor binding by circulating immunoglobulins.

We have characterized a circulating inhibitor of FSH receptor binding found in two patients with hypergonadotropic amenorrhea and myasthenia gravis. The inhibitor behaves as an immunoglobulin according to several criteria, including precipitation by 30% ammonium sulfate, migration on DEAE-cellulose chromatography, specific binding to protein A-Sepharose, characterization as a 7S protein in sucrose density gradients, and immunoprecipitation with specific antihuman immunoglobulin G. Evidence suggests that these antibodies are directed at determinants on or near the FSH receptor, and they may be responsible for the observed clinical FSH resistance.

Adolescent↗
PubMed1982

Development of the gonadotrophic resistant ovary syndrome in myasthenia gravis: suggestion of similar autoimmune mechanisms.

A woman with myasthenia gravis who developed hypergonadotrophic amenorrhoea was studied. This patient fulfilled all accepted criteria for the diagnosis of the gonadotrophin resistant ovary syndrome: high levels of serum LH and FSH by radioimmunoassay and urinary gonadotrophin excretion by bioassay, low serum oestradiol, lack of response to exogenous gonadotrophin and ovaries with multiple non-stimulated primordial follicles. The serum of this patient contained a substance which behaving like a gamma globulin, inhibited FSH specific binding to receptors in an in vitro system. This inhibitor was looked for in further patients with hypergonadotrophic amenorrhoea, other immunological diseases or myasthenia gravis with normal menses. Ovarian biopsy was not available in these patients. In all except one who also had the association of myasthenia gravis and hypergonadotrophic amenorrhoea, the inhibitor was not detected. It is suggested that development of antibodies directed against gonadotrophin receptors or a receptor related membrane domain may play a role in the mechanism of failure of gonadotrophin stimulation in some patients with the gonadotrophin resistant ovary syndrome.

Adolescent↗
PubMed1976

Plasma concentration of oestradiol-17beta in premature thelarche and in different types of sexual precocity.

Plasma Oe2 concentration was measured by radioimmunoassay in patients with premature thelarche, with precocious puberty and in 29 normal controls. The mean plasma Oe2 was 1.5 pg/ml (0-7.2) in normal prepubertal girls, 23.8 +/- 17.8 (SD) in pubertal girls, 50.2 (+/- 19.4) in the follicular phase, and 94.2 (+/- 19.5) in the luteal phase of normal adult females. Ten girls with premature thelarche had a mean of 7.7 +/- 6.6 pg/ml. Three of them showed higher values than the other 7, suggesting that in these cases, elevated levels of plasma Oe2 might have played a role in the development of breast tissue. Ten untreated girls with idiopathic precocious sexual development had a mean of 51.6 +/- 42.9 pg/ml while 6 patients treated with 150 mg per week of medroxyprogesterone acetate had a mean of 11.4 +/- 2.5 pg/ml. Two patients with Down's syndrome, hypothyroidism and sexual precocity had plasma Oe2 of 144 and 31.5 which fell to 24.7 and 8 pg/ml, respectively, after thyroid replacement. One girl with a granulosa cell tumour had a basal value of 304 pg/ml and a concentration of 27 pg/ml after surgery.

Adolescent↗