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Biomedical subjects

C Cervantes

Publications and source records attributed to C Cervantes.

At least 55 records · Page 3Linked to original sources
PubMed1982

Diurnal variations of pituitary and testicular hormones in paraplegic men.

The effect of the neuro-spinal cord injury upon testicular physiology was evaluated in six adult paraplegic (PPG) men by measuring the circulating levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), androstenedione, testosterone, and dihydrotestosterone every 4 hr throughout a 24-hr period. Three PPG men were studied within the first 3 months (acute period) and the other three patients 39-79 months (stabilized period) after trauma. Hormonal values were compared with eight age-matched normal adult males. Plasma FSH and LH were constantly above normal concentrations regardless of the sampling time and period of observation, whereas prolactin was higher than normal only during the first two months after trauma, returning to normal afterwards. Plasma androgens were consistently below normal during the first 3 months after injury, and returned toward normal thereafter. There may be a direct relationship between the time elapsed after the spinal cord injury and the plasma androgens concentrations. A possible role of PRL in testicular steroidogenesis is suggested.

Adult↗
PubMed1981

The relationship of plasma gonadotrophins and steroid concentrations to body growth in girls.

Plasma concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), 17 alpha-hydroxyprogesterone (17 alpha-OHP), 17 beta-oestradiol (Oe2) and progesterone (P) were measured in 352 healthy girls aged 6.0 to 15.9 years, as a function of age (CA), weight, height and calculated lean body mass (LBM) and total body fat (TBF). The earliest hormonal changes were a fall in mean plasma FSH concentrations together with a small but significant rise in plasma Oe2 well in advance of any sign of pubertal development. The next changes were a progressive rise in plasma FSH and 17 alpha-OHP concentrations without further increments in plasma Oe2; these changes corresponded to a mean body weight of 29.8 kg, a mean height of 132.0 cm (initiation of the adolescent growth spurt), a mean LBM of 24.7 kg and a mean TBF of 5.1 kg. The last events were a progressive rise in plasma LH and Oe2 and less marked in P, which occurred in association with a mean body weight of 40.0 kg, a mean height of 142.0 cm (time of peak velocity of weight and height gain), a mean LBM of 31.8 kg and a mean TBF of 9.1 kg. Significant quadratic equations were disclosed between plasma FSH and LH versus CA, weight, height and LBM, and a significant linear correlation was observed between each gonadotrophin and TBF. These results show an association, not necessarily causal, between a 'critical level' of body composition and hormonal changes at the start of the adolescent growth spurt, as well as with late hormonal events at the time of peak velocity in weight and height gain. On the other hand, LBM rather than TBF seems more closely associated with the initiation and progression of puberty.

Adolescent↗
PubMed1980

Plasma prolactin increase following electric stimulation of the amygdala in humans.

Plasma levels of PRL, GH, FSH, LH, and TSH were studied at various intervals after electric stimulation of the amygdala, in 5 patients in whom electrodes had been chronically implanted in the course of their evaluation for surgical treatment of uncontrollable, temporal lobe seizures. Electric stimulation, but not sham stimulation, elicited in all cases a significant rise in plasma PRL. Plasma GH rose only in 1 patient and TSH in another. No significant changes in plasma FSH or LH were detected. It is suggested that a fine control mechanism of the hypothalamic hypophyseal final common pathway for the control of PRL secretion, may be mediated either by the ventral amygdalohypothalamic pathway or via the stria terminalis.

Adolescent↗
PubMed1980

Immunological studies in breast cancer. Modifying activity of the serum (MSA).

Cancer patients' sera can modify results obtained with cell mediated immune reactions in vitro. We have investigated the modifying activity of breast cancer patients' sera on the inhibition elicited in a leukocyte migration inhibition test with two cellular extracts of breast cancer hepatic metastases (CaMa Hu-2 and CaMa Hu-3). These extracts elicited positive delayed hypersensitivity reactions in vivo in 80% of the patients studied with at least one of the two preparations, and 40% of the patients showed positive results with both preparations. In vitro similar quantitative results were obtained with the leukocyte migration inhibition test. With these antigenic extracts significant statistical differences were obtained between the cancer group compared to the controls with benign breast lesions (p < 0.01) and to the normal controls (p < 0.001). The modifying activity of the sera (MSA) showed three effects: blocking , potentiation and induction of inhibition of leukocyte migration in vitro in 80% of samples of sera tested. Blocking activity was associated mainly with not too advanced clinical stages, while potentiation and induction effects were associated with more advanced clinical stages. These MSA may be explained by assumed presence of tumor antigenic material, antibodies and immune complexes in breast cancer patients' sera.

Antigens, Neoplasm↗
PubMed1979

Body composition in hypopituitary dwarfs before and during human growth hormone therapy.

The clinical characteristics and body composition of eight hypopituitary dwarfs (10.2-21.6 yr) were analyzed before and after 6 and 12 mo of growth hormone therapy. 2 IU 3 times/wk. Before treatment, growth rate was 1.8 +/- 0.7 cm/yr, height age was 2.0-12.8 yr less, and bone age 2.0-11.1 yr less than chronologic age. Total body water (TBW), lean body mass (LBM), extracellular water (ECW), and intracellular water (ICW) were below normal for chronologic age, but normal for height. Muscle mass (MM) was below normal for age and height. During HGH therapy, growth rate was 7.1 +/- 1.6 cm/yr in the first 6 mo and 7.8 +/- 1.4 cm/yr during the next 6 mo; the ratio of change in height age to change in chronologic age was greater than or equal to 1.0 in all patients and the ratio of change in bone age to change in height age was 1.2 in one patient and less than or equal to 1.0 in the others. TBW, LBM, ECW, and ICW increased according to height increments; however, MM increased at a faster rate than expected from the height gains. Also, a relative or absolute loss of total body fat was recorded during the first 6 mo of therapy. It is suggested (1) that among the body composition parameters studied, muscle mass is the tissue most closely reflecting the lack of HGH and also its therapeutic benefits and (2) evaluation of body composition in hypopituitary dwarfs in response to HGH therapy shows striking changes not reflected by the determination of stature or weight alone.

Adolescent↗
PubMed1979

Accumulation of ethinylestradiol in blood and endometrium of women taking oral contraceptives: the sequential therapy.

A radioimmunoassay to quantitate ethinylestradiol (EE-2) in both plasma and endometrium is described. In 29 women under sequential oral contraceptive therapy (chlormadinone acetate, 2 mg, plus mestranol, 80 microgram) for 6 to 84 months, a single blood sample and a single endometrial sample were simultaneously obtained on different days of the pseudomenstrual cycle. In 24 women under 40 years of age the mean plasma EE-2 concentrations were similar during the first (989 +/- 94 pg/ml) and the second half of the cycle (1053 +/- 186 pg/ml) (P greater than 0.05). A similar finding was observed with regard to mean endometrial EE-2 concentrations (3.55 +/- 2.1 and 5.89 +/- 1.7 microgram/gm of wet tissue, respectively). On the other hand, five women over 40 years of age had plasma EE-2 concentrations similar to those of the previous group, but the mean endometrial EE-2 concentrations was 0.9 +/- 0.6 microgram/gm of wet tissue (P less than 0.05). Although plasma follicle-stimulating hormone and luteinizing hormone did not show midcycle peak values, complete suppression of both gonadotropins was not observed. These results show that endometrium has a great ability to concentrate EE-2, and this ability seems to be greater in women below age 40 than above. Whether or not this observation might be related to the known higher incidence of endometrial cancer in women less than 40 years old who have been under chronic sequential oral contraceptive therapy cannot be disclosed from this limited number of determinations.

Adolescent↗
PubMed1978

Effect of paramethasone acetate on women with secondary amenorrhea: a preliminary report.

Twelve women of normal weight (ages 17 to 36 years) with scanty menstrual bleeding were studied. They had no signs of virilization, gynecologic or endocrine pathology, or past history of hormonal treatment. Five women (group 1) experienced withdrawal bleeding after a 3-day course of chlormadinone acetate (2 mg/day) and the other seven did not (group 2). Daily venous blood samples were obtained 10 to 15 days afterward for 5 consecutive days of no treatment (control period) and during the next 5 days while the women received paramethasone acetate (PA), 2 mg/day (treatment period). In each plasma sample the concentrations of 17beta-estradiol (E2) and luteinizing hormone (LH; LER-907) were determined. The mean plasma E2 levels in group 1 were 35 +/- 8 and 86 +/- 10 pg/ml during the control and treatment periods, respectively (P less than 0.001), and the mean plasma LH levels were 28 +/- 6 and 94 +/- 34 ng/ml, respectively (P less than 0.001). No significant changes in plasma E2 and LH levels were observed in group 2 in either period. During the control period, the plasma E2 level in group 2 (14 +/- 2 pg/ml) was lower than that in group 1 (P less than 0.01); however, plasma LH levels were similar in both groups. The administration of PA for 5 months induced monthly ovulation in group 1 but not in group 2. These data suggest that the best results are obtained in women with optimal pretreatment levels of plasma E2.

Adolescent↗
PubMed1978

Hormonal content of plasma and endometrium of women taking oral contraceptives.

A total of 134 women were studied, 75 of whom were using cyclic steroid contraception (ethinyl estradiol, 0.05 mg plus norgestrel, 0.5 mg) and 59 of whom had normal ovaulatory cycles. By radioimmunoassay techniques simultaneous determinations were made of total estrogens (TE) and progesterone (P) in both plasma and endometrium and of FSH and LH in plasma, covering all days of the pseudomenstrual and true menstrual cycles. As expected, the ovulating women showed a midcycle peak of plasma TE and an increase in plasma P thereafter, while no cyclic variations were observed in the treated group. Correlations of endometrial concentrations of TE and P with plasma FSH and LH levels are discussed. In 13 of the 75 treated women elevations of endometrial P concentrations were present, presumably demonstrating the "escape phenomenon." The possible future value of endometrial hormone determinations is suggested.

Adult↗
PubMed1976

Propranolol effect on plasma glucose, free fatty acid, insulin, and growth hormone in Graves' disease.

A 3-hr glucose tolerance test was performed in 12 thyrotoxic patients before and after propranolol treatment for 30 days (120 mg/day). Plasma glucose, free fatty acid, insulin, and growth hormone levels were determined on each test and compared to each other and against nine clinically healthy volunteers. In eight thyrotoxic patients (subgroup A) an improvement in carbohydrate tolerance was observed after propranolol treatment, along with a fall in the previously elevated fasting FFA; no change in plasma insulin levels was observed. Plasma growth hormone levels were higher than normal both before and after propranolol; however, a 46% glucose-induced suppression was seen in both instances. In the other four patients (subgroup B) (who had had a marked and rapid weight loss) a deterioration of the previously normal glucosnificant changes in insulin levels. Elevated fasting plasma free fatty acids remained so despite propranolol treatment. Plasma growth hormone was higher than normal before and after propranolol; a late suppression (at 120 min) and no suppression at all were seen, respectively. After propranolol treatment, subgroup B had higher plasma free fatty acid than subgroup A in the fasting state and at 30 and 180 min. It is proposed that the improvement or deterioration in carbohydrate tolerance after propranolol treatment might be related to whether or not a satisfactory propranolol-induced lipolytic blockade is achieved, leading to a decrease in plasma free fatty acid levels, improved insulin sensitivity, and better peripheral glucose utilization. Therefore, a uniform dose of propranolol will not always be sufficient to obtain adequate lipolytic blockade, particularly if the thyrotoxic patient has had a marked and rapid weight loss.

Adolescent↗
PubMed1976

Familial true hermaphorodism in three siblings: plasma hormonal profile and in vitro steroid biosynthesis in gonadal structures.

The in vitro biosynthesis of estrogens and androgens by gonadal tissues of the ovotestes was studied in three siblings with familial true hermaphrodism and correlated with daily steroid and gonadotropin plasma levels. The probands were 15, 13, and 11 years old with normal male phenotype and external genitalia, grade III hypospadias, bilateral scrotal ovotestes, gynecomastia, and no uterus or fallopian tubes. Their karyotypes were 46XX both in peripheral lymphocytes and in gonadal fibroblasts, and no Y chromosome fluorescence was observed. A fusiform biopsy of each gonad was obtained, and the testicular and ovarian structures were excised and incubated for five days at 37 C with 3.8 muCi of 7alpha3H dehydroepiandrosterone, in Eagle's growth media, 95% O2 and 5% CO2. After standard procedures, four extractions with methylene chloride were performed, and the residue was assayed using Sephadex LH no. 20 chromatography. Testosterone (T), delta4androstenedione (delta 4), 5alphadehydrotestosterone (5alphaDHT), estrone (E1), estradiol-17 beta (E2) and estriol (E3) were measured. Also, during 16 consecutive days daily venous samples were obtained, and FSH, LH, E2, progesterone (P), and testosterone (T) were determined. The predominant steroids formed in vitro were estrogens, mainly E1 by either the testicular or ovarian structures. In the 11-year-old subject, the ovotestes were less active than in his oldest siblings. The patterns of androgen production showed that T was the principal androgen formed, followed by delta4 and minimal amounts of 5alphaDHT. The daily plasma hormonal profile resembled more closely a female pattern, specially in the 15 and 13-year-old patients. It is suggested that the ovotestes of these siblings had the enzymatic mechanisms necessary for estrogen and androgen biosynthesis, mainly E1 and T using a preferential metabolic pathway via androstenedione. Furthermore, it seems that the testicular structures had a greater capability to synthesize estrogens than the ovary.

Adolescent↗
PubMed1976

Improvement of intractable idiopathic epilepsy with chlormadinone acetate. A case report.

A 10-year-old boy with idiopathic epilepsy refractory to treatment from age 4 and with clinical signs of hyperandrogenism was treated with chlormadinone acetate (24 mg/day) during two alternate periods of 3 months. The administration of chlormadinone was associated with a marked clinical and electroencephalographic improvement as well as a concomitant decrease in the levels of plasma testosterone and delta4 androstenedione. No changes in plasma gonadotropins were observed. Placebo had no effect neither in seizures nor in the concentration of hormones in the plasma. Since chlormadinone acetate is not a very potent gonadotropin inhibitor in males, it is suggested that the clinical and electroencephalographic improvement associated with the use of this compound, might be the consequence of a decrease in the plasma levels of androgens, mainly testosterone.

Androstenedione↗