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Biomedical subjects

A Parra

Publications and source records attributed to A Parra.

At least 19 recordsLinked to original sources
PubMed1992

Esophageal atresia and tracheoesophageal fistula in two infants born to hyperthyroid women receiving methimazole (Tapazol) during pregnancy.

We report on 2 newborn infants with esophageal atresia and tracheoesophageal fistula (EA + TEF) born to hyperthyroid mothers receiving methimazole (Tapazol) before and during their entire pregnancies. Both mothers were euthyroid during gestation and developed hydramnios diagnosed during weeks 34 and 33 of gestation. Premature delivery (36.2 weeks of gestation) occurred in one case, and both newborn infants were small for date with palpable goiter; one of them had other associated malformations. Hypothyroidism was diagnosed by laboratory tests in both cases. Corrective surgery was undertaken, but both newborn infants developed septicemia and renal insufficiency and died in the first week of life. The EA + TEF and a normally placed enlarged thyroid gland were confirmed at necropsy. These cases represent a previously unreported example of the association of maternal ingestion of methimazole during pregnancy and EA + TEF.

Abnormalities, Drug-Induced↗
PubMed1992

[Changes in glucose metabolism during pregnancy: hospital experience].

The clinical heterogeneity of Diabetes Mellitus (DM) is also evident during the gestational period and thus, pregnancy could be complicated by a previously diagnosed DM or by diabetes that is first diagnosed during pregnancy (gestational diabetes or gestational alteration of the oral glucose tolerance test according with the degree of hyperglycemia). Independently of the stage at time of maternal diagnosis, the conceptus is at greater risk (probably since the time of conception) for abortion, genetic malformations, perinatal metabolic complications and death; these risks are apparently directly related with the time at diagnosis, duration and degree of metabolic alteration on the mother (mainly hyperglycemia) and the adaptive mechanisms on the product (hyperinsulinemia). Retrospectively, 412 pregnancies complicated with any type of carbohydrate metabolism alteration were studied in our service. The results demonstrated a high frequency of Gestational diabetes (42.2%) and of type II diabetes (35.9%); there was a good agreement with previous reports regarding the personal and family histories in the patients already known diabetic before pregnancy. The types of obstetric complications were similar to previous reports, but some of them with a greater frequency in our patients, namely hydramnios, toxemia, and urinary tract infection, and ketoacidosis with a minor frequency. We also observed an increased frequency of congenital malformations on the products. On the other hand, the metabolic complications of the newborn were similar to other reports with a slight predominance on the babies of known diabetic mothers prior to gestation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Basal and metoclopramide-stimulated prolactin (PRL) serum levels in users and non-users of a copper intrauterine device (TCu-380 IUD).

The study was undertaken to analyze the basal and metoclopramide-stimulated serum PRL levels in healthy parous women users (group 1, n = 12) and non-users (group 2, n = 12) of a TCu-380 IUD. All women had regular menses and were studied between days 18 to 22 of their cycle; none had lactated nor regularly ingested any type of medication during the last six months. After a 10-12 hour overnight fast, peripheral venous blood samples were obtained through an indwelling catheter at -30, -15 and 0 minutes and at 60, 90 and 120 minutes after oral metoclopramide (10 mg). There were no significant differences in serum PRL between both groups, in basal levels nor throughout the test, whether analyzing the mean values at each sampling time, the sum of PRL levels from 60-120 minutes, or the peak levels. No correlation was observed between PRL levels and any of the clinical or obstetric characteristics of the women in both groups. Serum progesterone was greater than or equal to 4.0 ng/ml in all women. Thus, the use of alpha TCu-380 IUD did not induce any significant changes in basal nor in stimulated serum PRL levels.

Administration, Oral↗
PubMed1991

A computerized system for measuring time perception in human subjects.

We describe an integrated computerized approach to the design, execution and recording of time perception experiments in human subjects. The program is menu driven and runs on an IBM-compatible microcomputer. The method is easy to use, non-obtrusive to the subjects, and flexible enough to allow the investigator to design studies with a wide range of experimental protocols and study parameters. The fact that the results do not depend on proctor bias or subject-proctor interactions are additional advantages. The technique was applied to study the effects of prompt positive feedback on the time perception of normal human subjects who undergo training. The results of this study are reported.

Adult↗
PubMed1991

Differential prolactin response to oral metoclopramide in nulliparous versus parous women throughout the menstrual cycle.

OBJECTIVE: To analyze if serum prolactin (PRL) changed throughout the menstrual cycle and if parous women have lower PRL than nulliparous women. DESIGN: A prospective study of PRL was performed in basal conditions and during oral metoclopramide stimulation on days 7, 14, and 21 of menstrual cycle. SETTING: Instituto Nacional de Perinatología, third level medical institution. PATIENTS: Four parous (group A) and seven nulliparous (group B) healthy volunteer women entered and finished the study. INTERVENTIONS: Women were studied each day before and every 30 minutes during 2 hours after oral metoclopramide (10 mg). MAIN OUTCOME MEASURE: Duplicate PRL determinations were performed by radioimmunoanalysis. Hypothesis was formulated before data collection. RESULTS: Group A and B had similar basal PRL levels and no within group differences existed in response to metoclopramide, regardless of the day studied. Group A had lower PRL increments than group B from 60 to 120 minutes on days 14 and 21 (P less than 0.05); the peak increments also were lower on days 7, 14, and 21 (P less than 0.05). CONCLUSIONS: Parous women had a diminished PRL response. Although the dopaminergic tone was similar throughout the menstrual cycle within each group, two distinct levels of dopaminergic tone existed in parous and nulliparous women.

Adult↗
PubMed1989

Learned immobility explains the behavior of rats in the forced swimming test.

The rat forced-swimming test (FST) is widely used for screening substances with a potential antidepressant effect. The rat immobility shown in the FST has been interpreted as "behavioral despair" and has been suggested as an animal model of human depression. In the following series of experiments it is shown that measuring rat mobility by an automatic recording device is more accurate than measuring immobility time by direct observation (Experiment 1 and 5). The automatic recording procedure was tested with imipramine and mianserin showing similar results to those reported in the literature using a direct observation procedure by the researcher (Experiment 2). In Experiment 3 it was demonstrated that: (a) rat mobility decreased with experience, (b) switching water depth on Day 2 of the test increased mobility and (c) anisomycin acts as a false positive. In Experiment 4 the possible state dependent effect of imipramine in the FST was studied. The effect of imipramine on rat behavior in the FST is not state dependent. The imipramine-saline group shows greater mobility than the saline-saline group and does not differentiate from the imipramine-imipramine group. Thus, it was suggested that imipramine could interfere with the acquisition and/or consolidation processes. In Experiment 5, it is shown that a single dose of 25 mg/kg of imipramine, administered before or immediately after training on Day 1, increases rat's mobility on Day 2, thus suggesting that imipramine alters the consolidation process. From these results it is suggested that the behavioral process involved in the FST is "learning to be immobile" instead of "behavioral despair" as previously suggested in the literature.

Animals↗
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

Effect of prolactin on the calcium binding and/or transport of ejaculated and epididymal human spermatozoa.

The prolactin concentration in human seminal plasma and in human epididymal cauda fluid was assessed by radioimmunoassay. The prolactin concentration in cauda plasma was found to be similar to that found in male blood serum (5.5 to 9.1 ng/ml) and significantly lower than the concentration of the hormone found in seminal plasma obtained either from euspermic (48 +/- 12 ng/ml) or from vasectomized volunteers (50 +/- 10.2 ng/ml) (P less than 0.001). Calcium binding and/or transport in ejaculated spermatozoa were found to be little (0.29 +/- 0.08 nmoles/10(8) cells) and dependent on a quickly saturable process. The addition of 200 ng of human prolactin/ml induced a 60% increase in this parameter, while 50 ng of prolactin/ml were ineffective. Epididymal human spermatozoa differ from ejaculated sperm cells in showing greater, time-dependent, calcium binding and/or transport under basal conditions (2.00 +/- 0.35 nmoles/10(8) cells/hour), and in being more susceptible to the stimulating action of prolactin (4.4 +/- 0.68 nmoles/10(8) cells/hour in the presence of 50 ng of prolactin/ml).

Binding Sites↗
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↗
PubMed1979

Effect of hemodialysis on glucose tolerance in children with chronic renal failure.

Five uremic (7.0 - 15.2 years), non-dialyzed children treated medically (group 1) had an intravenous glucose tolerance test (0.5 g/kg). Blood samples were obtained at frequent intervals and duplicate determinations of plasma glucose (glucose-oxidase method on Somogyi-Nelson protein-free filtrates), insulin and free fatty acids were performed. The same study was performed in eleven children (12.3 - 18.0 years) with chronic renal failure undergoing long-term hemodialysis (group 2), before and two hours after dialysis. Results were compared to a group (group 3) of eight healthy children (7.5 -- 17.5 years). In group 1 a "normal" insulin response was observed in the presence of hyperglycemia and the plasma glucose clearance was in the diabetic range. Twice weekly hemodialysis produced no beneficial acute effects on group 2, based on absolute glucose values or plasma glucose clearance rates, on groups as well as on individual basis; however, a clear hyperinsulinemia was present which was of even higher magnitude three and six months after the initial study. These results demonstrated that chronic hemodialysis had no beneficial acute effects on plasma glucose concentration or plasma glucose clearance rate. However, it may have obvious long term beneficial effects on glucose tolerance by enhancing pancreatic insulin release (to overcome peripheral insulin resistance) to such an extent as to maintain a normal carbohydrate tolerance.

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

Suprahypophyseal dysfunction in a patient with asexual ateleiosis.

The neuroendocrine function of a 19 years old female dwarf with primary amenorrhoea and lack of sexual development (asexual ateleiosis) was studied. Undetectable fasting plasma levels of growth hormone (GH) and a lack of response to three different provocative stimuli was observed. Oestrogen administratin did not modify the GH response. Thyroid and adrenal function were within normal limits. Undetectable plasma levels of immunoreactive oestradiol and lack of oestrogenic activity in vaginal smears indicated absence of ovarian function. Low levels of circulating gonadotrophins with a significant rise after synthetic LH-RH administration was demonstrated, while clomiphene citrate failed to induce ovulation. Following 6 months of continuous GH administration a significant increase in the growth rate was evident, whereas no pubertal development was observed. These data are interpreted as demonstrating the suprahypophyseal origin of the sexual infantilism in a patient with inappropriate GH secretion. It is suggested that a combined deficiency of LH-RH and GH-RH may account for the aetiology of this disorder.

Adrenocorticotropic Hormone↗
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↗