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Biomedical subjects

S Díaz

Publications and source records attributed to S Díaz.

At least 109 records · Page 6Linked to original sources
PubMed1982

Zinc, prolactin, gonadotropins, and androgen levels in uremic men.

This study correlates plasma levels of Zinc (Zn) and some pituitary and testicular hormones in 20 uremic men (aged 17-58 years) on a weekly peritoneal dialysis program. Patients were compared to 12 healthy male volunteers (aged 28-40 years). In uremic men, plasma androstenedione (A) was elevated, while testosterone (T), dihydrotestosterone (DHT), and Zn were low. On a group basis, plasma follicle stimulating hormone (FSH) and luteinizing hormone (LH) were normal while prolactin was increased. A negative correlation was observed between plasma A and LH levels, as well as between the A/T+DHT ratio and plasma Zn concentrations. Our results suggest a diminished A-to-T conversion and point to the possible role of Zn in the enzyme activity of the 17 beta-hydroxysteroid dehydrogenase.

Adolescent↗
PubMed1982

Endocrine profile in patients with chronic renal failure under zinc replacement.

The plasma levels of androstenedione (A), testosterone (T), dihydrotestosterone (DHT), follicle stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL) were studied in 15 men (aged 24-50 years) with chronic renal failure under periodic peritoneal dialysis, before and after 50 mg of elemental zinc (Zn) orally, twice a day for three weeks. Before treatment, they were divided into three groups: group I, plasma A above normal and PRL less than 100 ng/ml; group II, low or normal A levels with PRL less than 100 ng/ml; and group III, normal or high A levels with PRL greater than 100 ng/ml. After oral Zn, plasma FSH, LH, and PRL were unchanged in all groups; however, in groups I and II plasma A was within normal T and DHT rose significantly, the A/(T+DHT) ratio decreased to normal, and the T/DHT ratio rose above normal. In group III plasma androgens remained low and androgen ratios were unchanged. Oral Zn seems to improve the conversion of A to T and also uncovered the possibility that plasma PRL levels greater than 100 ng/ml might cause a blockade in the 5 alfa-reductase.

Adult↗
PubMed1982

Testicular function in men with chronic renal failure and transplant recipients under bromoergocriptine therapy.

Plasma zinc (Zn), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and androgens concentrations were determined in 15 male patients with chronic renal failure who were successful recipients of kidney transplant. After 25 +/- 8.5 months of the renal transplant, Zn levels were (88 +/- 4 g/dl) lower than in the control group (116 +/- 5 micrograms/dl). Normal concentrations for androstenedione (A) (0.63 +/- 0.05 ng/ml) and testosterone (T) (3.31 +/- 0.15 ng/ml) were found. Dihydrotestosterone (DHT) levels (0.38 +/- 0.01 ng/ml) were lower than normal (1.11 +/- 0.09 ng/ml), suggesting a blockade in the conversion of T to DHT. Eleven of the 15 patients showed higher PRL levels (9.5 +/- 0.8 ng/ml) in contrast with the normal group (3.6 +/- 0.3 ng/ml). Ten patients received orally 2-alpha-bromoergocriptine (BEC) 2.5 mg/day for ten days. Plasma PRL decreased to 2.6 +/- 1.0 ng/ml (p less than 0.001), but A and T levels did not significantly change; however, DHT increased from 0.38 +/- 0.02 ng/ml to 0.72 +/- 0.04 ng/ml (p less than 0.01). All patients showed an increase in both gonadotropins before BEC without significant changes after treatment. The high PRL levels may be responsible for the impaired conversion of T to DHT, possibly by interference with the enzyme 5 alpha-reductase.

Adult↗
PubMed1981

Plasma levels of levonorgestrel in women during longterm use of norplant.

Levonorgestrel plasma levels were determined by a specific radioimmunoassay in a group of 110 women at various intervals between 1 and 60 months following implantation of six silastic capsules containing levonorgestrel (Norplant). The implants were placed subdermally in the volar aspect of the forearm. Blood samples were taken twice a week for six consecutive weeks in each subject. Blood drawn from the antecubital vein ipsilateral to the implant site contained two to three times more levonorgestrel than contralateral samples. Average systemic plasma levels represented by contralateral samples ranged from 0.35 +/- 0.03 to 0.29 +/- 0.02 ng/ml (Mean +/- S.E.) in the first and fifth year, respectively. The difference between these values is statistically significant at the 5% level. The results of the regression analysis of individual levels suggest that the decline observed throughout the first five years is mainly due to an early decrease taking place in the first two years. When the sampling period was repeated in the same subjects two or three times 10 to 24 months apart, no significant difference was found. A significant negative correlation was found between plasma levonorgestrel levels and body weight and body surface. The data indicate that the contraceptive efficacy of Norplant during the first five years of use is associated with sustained release of levonorgestrel and is in keeping with the estimated life span of Norplant of seven years.

Female↗
PubMed1981

[Changes in the nutritional status of the lactating women during exclusive lactation].

In order to evaluate the influence of breast feeding upon selected nutritional parameters of lactating women, several anthropometric and biochemical measurements were performed during the interval between 40 and 180 postpartum days in 54 women in full and satisfactory nursing. Only one significant change was detected in measurements done for nutritional assessment: loss of body weight. No changes were detected in hemoglobin levels or in serum protein and albumin. There was high variability in body weight changes with a mean loss of 1.5 kg due especially to a loss in fat body mass and, in a lesser proportion, to loss in lean body mass. The mean food intake did not change during the observation period. The mean caloric intake was 2,771 cal/day at the beginning and 2,737 cal/day in the end of the study. A significant correlation was established between the individual energetic intake and the body weight changes of lactating women. The allowance of 2,750 cal/day suggested by FAO/WHO for lactating women seems adequate for the health of women in a normal nutritional condition, but apparently insufficient to overcome undernutrition in women who initiate lactation with this condition. In spite of the small nutritional impact observed, our results support the need for food supplementation programs destined to lactating women, with special orientation to undernourished women of low socioeconomic level.

Adolescent↗
PubMed1980

Studies on the duration of ovum transport by the human oviduct. III. Time interval between the luteinizing hormone peak and recovery of ova by transcervical flushing of the uterus in normal women.

This article deals with attempts to time the onset and duration of the ovum's sojourn in the endometrial cavity of women. Recovery of the ovum from the uterus was attempted by means of transcervical flushing of the cavity 48 to 216 hours after the luteinizing hormone (LH) peak in plasma. A single flushing or repetitive flushings done at 24-hour intervals in the same cycle were performed in different subjects. With both modalities, the adverse effects were mild and few. Of 132 flushings done in 76 subjects, 90 were considered to be technically adequate from the point of view of recovering over 50% of the flushing volume. Twenty ova were recovered. Technically adequate flushings and adequate timing of the LH peak were accomplished in 39 cycles. In this group, 13 ova were recovered between 96 and 168 hours after the LH peak. The highest yield of ova per flushing was obtained from 120 to 168 hours with an average of 37% and a range of 25% to 50%. Limitations of the technique are discussed. Some uncertainties persist which prevent the drawing of definitive conclusions about how soon after the LH peak the egg enters the uterine cavity, how long it stays there, and what is the extent of individual variation. However, recovery rates at various times after ovulation agree with previous data derived from transfundal flushing and indicate that the ovum is usually transferred to the uterus between 96 and 120 hours after the LH peak is retained there for several days.

Adult↗
PubMed1980

Plasma levels of levonorgestrel in women during longterm use of Norplants.

Levonorgestrel plasma levels were determined by a specific radioimmunoassay in a group of 110 women at various intervals between 1 and 60 months following implantation of six silastic capsules containing levonorgestrel (Norplant). The implants were placed subdermally in the anterior aspect of the forearm. Blood samples were taken twice a week for six consecutive weeks in each subject. Blood drawn from the antecubital vein ipsilateral to the implant site contained two to three times more levonorgestrel than contralateral samples. Average systemic plasma levels represented by contralateral samples ranged from 0.35 +/- 0.03 to 0.29 +/- 0.02 ng/ml (Mean +/- S.E.) in the first and fifth year, respectively. The difference between these values is statistically significant at the 6% level. The results of the regression analysis of individual levels suggest that the decline observed throughout the first five years is mainly due to an early decrease taking place in the first two years. When the sampling period was repeated in the same subjects two or three times 10 to 24 months apart, no significant difference was found. A significant negative correlation was found between plasma levonorgestrel levels and body weight and body surface. The data indicate that the contraceptive efficacy of Norplants during the first five years of use is associated with sustained release of levonorgestrel and is in keeping with the estimated life span of Norplants of seven years.

Adult↗
PubMed1980

Ectopic pregnancies associated with low dose progestagen-releasing IUDs.

Dimethyl-polysiloxane capsules containing pure progestagens were attached to Tatum's T IUDs and tested in 594 fertile women for contraceptive performance. The control group was represented by 71 women who received identical devices containing barium sulphate instead of steroid and 100 women who received a Copper T-200. The progestagens and the doses tested were megestrol acetate (4.8, 19.2, 26 and 32 micrograms/day; levonorgestrel (2.1, 3.4 and 8.5 micrograms/day); norethindrone (18 micrograms/day); R2323 (28.6 and 45 micrograms/day); and norgestrienone (26 micrograms/day). Twelve pregnancies were diagnosed during 5201 woman-months of exposure accumulated within the first year of use among users of the steroid-bearing IUDs. Five of these were ectopic gestations. Ten pregnancies, all uterine, were detected during 1701 woman-months of exposure in the control group. Intrauterine delivery of progestagens by means of a carrier IUD is effective in decreasing the pregnancy rate but it might effect postovulatory events in a way which increases the rate of tubal implantation. Because of this property, progestagen-releasing IUDs should be limited to doses that assure maximal effectiveness to avoid increasing the risk of ectopic pregnancy.

Adolescent↗
PubMed1980

PMN cell phagocytic function in malnourished patients with zinc uptake.

Zinc effects on phagocytic activity depend upon its serum concentration. According to certain experimental findings, a decrease in zinc serum concentration is parallel to a deficiency in host defense mechanisms and thus we were interested in studying the effect of zinc sulphate in the phagocytic function of polymorphonuclear cells of 15 zinc deficient patients with III degree malnourishment. In all patients, zinc serum determinations were made before and after zinc intake and chemotaxis, phagocytosis and NBT reduction tests were made at 7, 14 and 30 days. Results are compared with an eight patient group with similar clinical and nutritional characteristics observing an improvement in PMN cell phagocytic activity in patients with zinc uptake (p < 0.001). No differences were observed in a chemotaxic phagocytosis and NBT reduction tests in regard to the time during which patients did not receive zinc uptake.

Child, Preschool↗
PubMed1978

Studies on the duration of egg transport by the human oviduct. II. Ovum location at various intervals following luteinizing hormone peak.

The location of ova in the genital tract between 24 and 144 hours following the LH peak was determined in 23 normal women. Nineteen eggs were found in the Fallopian tubes between 24 and 96 hours and five eggs were recovered from the endometrial cavity between 96 and 144 hours following the LH peak. According to the present data and considering that ovulation occurs in the human subject nearly 17 hours after the LH peak, it is concluded that the transport of unfertilized ova in women is characterized by a period of retention in the ampulla, which lasts approximately 72 hours, followed by rapid transit through the isthmus and appearance of the ovum in the endometrial cavity around 80 hours after ovulation.

Adult↗
PubMed1978

[Intestinal amebiasis in children II. Evaluation of various diagnostic technics and different therapeutic regimens].

The diagnostic usefulness of different laboratory tests was evaluated in 20 cases of invasive intestinal amebiasis: the direct coproparasitoscopic exam in mucus obtained by rectoscopy was positive in 90.0 per cent of cases; the same exam done in mucus obtained by the spoon technique was positive in 40.0 per cent. The serum antibodies investigated by the counterimmunoelectrophoresis technique were found in 40.0 per cent of the cases in the first blood sample obtained at the hospital admisssion, and 15 days later this percentage increased to 66.6 percent. The fecal antigen studied by the ELISA technique was positive in 70.0 per cent of the cases. Simultaneously, the therapeutic effectiveness of emetine and metronidazol was evaluated, and with both therapeutic programs total recovery was obtained in 100.0 per cent of the cases; there were no significative differences in the symptoms duration after the start of therapy, and side effects were not observed. The results must be considered preliminary, because the calculated full sample has not been concluded.

Adolescent↗