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J A Bermudez

Publications and source records attributed to J A Bermudez.

16 recordsLinked to original sources

Correlation study between prolactin and androgens in male patients with systemic lupus erythematosus.

The hypothalamic-pituitary-gonadal axis was studied in 8 male patients with systemic lupus erythematosus (SLE), both before and after intravenous administration of luteinizing hormone-releasing hormone (LH-RH). We provide evidence herein that resting serum levels of estrone are increased and that resting serum testosterone (T) and dihydrotestosterone (DHT) levels are decreased in male patients with SLE. The decreased serum T levels were observed even after the IV administration of 25 micrograms of LH-RH. The high basal serum prolactin (PRL) levels observed in these patients with SLE is a novel finding not previously reported that could explain why serum T and DHT levels are low in this syndrome. We observed a decrease in the pituitary response to LH-RH stimulation; this low response could also be a hormonal manifestation of hyperprolactinemia. Furthermore, it has been suggested that PRL plays a role in immunocompetence, and therefore it could have influence either directly or indirectly in the altered immunoregulation observed in SLE.

Adult↗

A new inherited variant of the 3 beta-hydroxysteroid dehydrogenase-isomerase deficiency syndrome: evidence for the existence of two isoenzymes.

The clinical and endocrine features of a unique form of adrenal insufficiency secondary to an inherited deficiency of 3 beta-hydroxysteroid dehydrogenase-isomerase (3-HSD) were studied. The propositus was a 19-yr-old man with a history of repeated episodes of acute adrenal crisis. Family study disclosed that a 6-yr-old female sibling also was affected, and a third sibling had died during the course of an adrenal crisis. The diagnosis of adrenal insufficiency was established on the basis of extremely low serum cortisol levels and urinary 17-hydroxycorticosteroid excretion with concomitantly elevated serum ACTH levels and lack of cortisol response to ACTH administration. Impairment of C-21 steroid 3-HSD activity was strongly suggested by persistency elevated serum 17-hydroxypregnenolone to 17-hydroxyprogesterone and pregnenolone to progesterone ratios, their significant increase after ACTH administration, and their return to normal during cortisol therapy in both patients. Nevertheless, the serum dehydroepiandrosterone to androstenedione ratio, both basally and after ACTH and/or hCG stimulation, was normal. These findings coupled with the normal phenotypic development and onset of puberty in the two patients indicated intact C-19 steroid 3-HSD activity. The overall results indicate an inherited impairment of 3-HSD activity confined only to C-21 steroid substrates and, thus, suggest the existence of at least two 3-HSD isoenzymes under independent genetic regulation.

3-Hydroxysteroid Dehydrogenases↗

Morphophysiological correlation of boar Leydig cell development during postnatal stage.

To analyze the possible correlation between steroidogenic activity of the Leydig cells and their morphology and ultrastructure in the boar testes at different ages, testes from six Yorkshire boars were obtained by orchidectomy at 8,14,28,40,70,78,86,94 and 100 days of age. Using representative sections of testicular parenchyma, light as well as transmission electron microscopic studies were performed. Homogenized, albuginea-free tissue was further used for quantitative estimation of total proteins and metabolic pools of androstenedione (A), testosterone (T) and 5 alpha-dihydrotestosterone (DHT). Under light microscopy, abundant hyperplastic Leydig cells were observed from 14 to 40 days, thereafter was a decrease in their size and number. Spermatogenesis remained in the spermatogonia stage while the tubules increased in diameter until age 80 days; from 90 days on, pachytene primary spermatocytes could be found. A well developed smooth endoplasmic reticulum was observed in Leydig cells from the 8th postnatal day. Metabolic pools from age 8 to 28 days showed a decrease for T and A from 4.33 to 1.78 and 2.51 to 0.48 microgram/mg protein respectively, maintaining thereafter the same levels throughout the age-span studied. However, DHT was found at low levels from the beginning of neonatal period (from 0.07 to 0.38 microgram/mg protein).

Aging↗

Preliminary characterization of a new androgen-binding protein in human seminal plasma.

In order to obtain comparative analysis between the steroid binding proteins from blood serum and seminal plasma, fresh samples were incubated and assayed in parallel with the following tritiated steroids: dihydrotestosterone, testosterone, cortisol, progesterone and estradiol. Thereafter, and using techniques such as (1) polyacrilamide disk gel electrophoresis with elution of proteins from the gel slices, (2) ammonium sulphate precipitation, (3) enzymatic hydrolysis, and (4) gel filtration on Sephadex G-100, there was a resemblance in the electrophoretic patterns confirming the presence in both fluids of proteins like TeBG, CBG, and Albumin, previously described in blood serum. In seminal fluid, but not in blood serum, another small protein with androgen binding capacity was found and its preliminary characterization demonstrated: disappearance with enzymatic treatment, low molecular weight, negative charge, and precipitation range with ammonium sulphate from 30 to 35%. Its elution profile on Sephadex G-100 was contaminated with albumin.

Androgen-Binding Protein↗

[Quick radioimmunoassay method for the determination of estrogens].

The aim of this report is to describe a quick method for measuring plasma estrogens by radio immunoassay in one day. Briefly, 1000 cpm of estradiol-3-H were added to 0.1 to 1.5 ml of plasma or serum to calculate losses during the procedure. After ether extraction and without any purification step, aliquots for tracer recoveries and the radioimmunoassay were taken. The antiserum working dilution was 1:100,000. The incubation of the antiserum at 37degreesC with the tritiated and cold estradiol lasts one hour. The free and bound fractions were separated with charcoal/dextran. With this method, 95% of estradiol, 16% of estrone and 6% of estriol are quantified. Other steroids normally present in plasma produce no interference. The minimal detectable level is 10 pg. Pasma and water blanks are indistinguishable of zero (C.V. 1%). Intra-analysis coefficient of variation is 6.1%. Mass recovery of estradiol (5 ng), estrone (5 ng) and estriol (5ng) are 4.75, 0.83 and 0.31 ng, respectively. Tracer recoveries are 92.6%. When plasma levels of estradiol are determined during menstrual cycle, normal and/or pathological pregnancy, by either the method described herein or measured selectively, the results show no significant differences. Finally, practical usefulness of this method is stressed, inasmuch results are obtained in six hours and one person can easily perform 200 samples in one week.

Blood Specimen Collection↗

Blood levels and production rate of 17-hydroxypregnenolone in man.

A reliable radio-ligand assay has been developed for the measurement of 17-hydroxypregnenolone in human peripheral vein plasma. The mean plasma concentration of 17-hydroxypregnenolone was, in men, 1.9 mmug/ml; and in women, 3.5 mmug/ml. These means were not significantly different from each other, and the levels were the same in the follicular and luteal phases of the menstrual cycle. In women, the adrenal cortex was the source of the 17-hydroxypregnenolone; in men, 40% was produced by the testis. Since the metabolic clearance rate was about 2000 liters/24 hr production rate estimates were 4-7 mg/24 hr. The conversion of blood 17-hydroxypregnenolone to blood 17-hydroxyprogesterone and dehydroepiandrosterone was measured. This varied from 5 to 20%. Thus, in women during the follicular phase, 17-hydroxyprogesterone derived from blood 17-hydroxypregnenolone could be the major fraction of the 17-hydroxyprogesterone production rate. Blood 17-hydroxypregnenolone is a minor precursor of blood dehydroepiandrosterone.

17-alpha-Hydroxypregnenolone↗

[Thalidomide in Brazil: monitoring with shared responsibility?].

This paper discusses issues related to the regulation and rational use of thalidomide in Brazil, by means of a historical approach comprising three different stages. The first part is a historical review of the controversial drug since it was first synthesized, then marketed and subsequently banned during the 1950s and 60s, until the present, when an apparently irreversible process of rehabilitating the drug is under way. Brazilian experience with the use of thalidomide is described, emphasizing legal, political, and institutional work led by two social movements, the Brazilian Association of People with Thalidomide Syndrome (ABPST) and the Movement for Reintegration of People with Hansen's Disease (Morhan). The article describes the results and analyzes an active search of new cases in what is a second generation of thalidomide syndrome in Brazil. Finally, based on clinical and scientific evidence of thalidomide's therapeutic efficacy, the growth of social movements struggling both for and against authorization of the drug, and a restrictive regulation proposed by the Ministry of Health, the article discusses the implementation of policies for the regulation and rational use of thalidomide in Brazil.

Adolescent↗

[Pharmaceutical care in primary health care: the experience of 3 Brazilian States].

In the context of recent changes in the Brazilian drug supply system at the national level, mainly the deactivation of CEME (a government agency under the Ministry of Health that dealt with drug supply policy) and the increasing decentralization of activities under the Unified National Health System (SUS), three Brazilian States - Paraná, São Paulo, and Minas Gerais - have established programs for the distribution of essential drugs for primary health care. A nationwide program for the procurement and supply of 32 drugs for primary health care (the so-called "Basic Pharmacy Program") is currently being implemented by the Ministry of Health, to be decentralized subsequently. This article discusses the establishment of State-level drug policies for primary health care through the analysis of the three pioneering programs encompassing drug selection, procurement, storage, distribution, and use.

Brazil↗