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Biomedical subjects

G Paz

Publications and source records attributed to G Paz.

At least 73 records · Page 4Linked to original sources
PubMed1984

Serum antibody levels in human paragonimiasis before and after therapy with praziquantel.

Enzyme immunoassays (ELISA) and indirect haemagglutination (IHA) were used to determine IgG and IgE serum antibody levels in 43 patients from Ecuador before and after therapy with praziquantel. ELISA indicated infection more sensitively than IHA. The tendency of increasing antibody levels between the first and second month after therapy was more distinct when measured by IHA, whereas the decreases of antibody levels between the third and sixth month after treatment was more distinct when measured by ELISA. The IgG ELISA for detecting long persisting antibody was more sensitive than IHA.

Antibodies↗
PubMed1982

Prolactin receptors in interstitial cells of testes from rats at different stages of development.

The developmental pattern of prolactin receptors was examined in intact interstitial cells isolated from testes of 19-day old foetuses (F19), 1 to 45-day immature (N1 to N45) and adult animals. The prolactin binding activity in F19 interstitial cells is low, being 27% of that found in cells of the adult. There is an abrupt 60% increase in prolactin binding immediately after birth (N1), followed by a slow, but gradual, increase for the next 34 and adulthood which follows an increment in serum prolactin concentrations after day 24. Equilibrium analysis revealed that the receptors In interstitial cells from N1, N34 and adults have similar affinity (Kd = 2.7 to 3.3 x 10(-10)M) for prolactin. However, cells from adults contain twice as many prolactin receptors per cell as that of immature animals. This increase in prolactin receptors may play a role in the modulation of interstitial (Leydig) cell function during sexual maturation.

Animals↗
PubMed1982

Human sperm penetration into cervical mucus in vitro: correlation between its quality, penetration capacity and velocity.

In vitro penetration tests of human sperm into cervical mucus were introduced in order to study the interaction between sperm and cervical mucus. In the present study the correlation between sperm velocity and penetration value has been assessed. 197 semen samples were run in the in vitro penetration test using semen of different qualities and cervical mucus of good quality. No differences were found either between sperm velocity in cervical mucus (17.3 +/- 0.9 micrometers/s) and in semen (19.9 +/- 0.8 micrometers/s) or at different distances measured along the flat capillary tube (1, 2 and 3 cm). A highly significant correlation was found between sperm velocity and penetration value rates (p less than 0.0001, r = 0.9). Thus, sperm velocity in semen is a variable of great importance in the assessment of the quality of the ejaculate.

Cervix Mucus↗
PubMed1982

Penetration of human ejaculated spermatozoa into human and bovine cervical mucus. II. Pattern and velocity of penetration.

The pattern of penetration of human ejaculated spermatozoa into human cervical mucus (HCM) and bovine cervical mucus (BCM) was studied in an in vitro penetration system by means of plate capillary tubes. Sperm penetrate the HCM in a unique pattern making their way progressively forwards in a one-way direction in between the filaments. In contrast, sperm move preferably forward in BCM. The different patterns are probably due to different organizations of the glycoproteins. The penetration values (PV) were also different in the two systems when studied after short periods of incubation (15 and 30 min), but incubation for 1 h brought both systems to the same rate of PV. Thus, this period is enough to overcome the differences between the patterns of penetration. Sperm velocity in semen, in HCM, and in BCM were the same. Cervical mucus (CM) did not affect sperm velocity. A strong correlation (r = 0.8) was found between sperm velocity in the semen and its PV rate either in HCM or in BCM. The results of this study recommend the use of BCM as a reference CM in cross penetration tests and suggest its establishment as a routine method for assessment of sperm quality.

Animals↗
PubMed1980

Quality of semen obtained from 627 fertile men.

Six hundred and twenty seven men, whose wives conceived within 6 month of their semen analysis, were included in this study. Attention was focused on 516 men where conception occured within 3 months of semen analysis. The quality of the seminal plasma (volume pH, fructose and calcium concentrations) and the spermatozoal characterization (concentration, motility, vitality and morphology) are given in details. It was concluded that spermatozoal motility and morpholoy are the most crucial factors in determining its fertilizing capacity. Measurement of vitality is important only in hypokinetic specimens. Sperm density is a limiting factor only below 10 million/ml. A widely scattered range of sperm concentration was found among the fathered men which may indicate that the incidence of pregnancy is a multifactorial statistical probability which increases when the quality of the semen is high.

Adult↗
PubMed1980

Varicocelectomy and male fertility: comparison of semen quality and recurrence of varicocele following varicocelectomy by two techniques.

Two hundred thirty-eight infertile men aged between 20 and 50 years suffering from left varicocele underwent ligation of the internal spermatic vein. The patients were operated on using Ivanissevich technique IT (210 patients) or the Bernardi technique BT (28 patients). In the BT group recurrences were found in 7.1% as against 28% in the IT group. The low rate of recurrence found in the BT group might be due to the fact that the patients were under local anaesthesia and collaborated with the surgeon. Varicocelectomy was followed by significant improvement in sperm quality 3 to 9 months after operation. Improvement among the fertile men was more rapid than among the infertile men. Sperm concentration improved significantly in 50% of the cases. Sperm motility improved in 37% of the cases, while morphology improved only in 29% of the cases. Sperm vitality was identical in response to that of motility. Varioocelectomy did not cause any change in the seminal plasma constituents (volume, pH, fructose). Improvement in sperm quality was identical in the IT and BT groups, as was the impregnation rate. 94 couples reported pregnancies 39.5%), which occurred within 2 years after operation (12 +/- 1.5 months mean +/- SEM). No correlation was found between size of varicocele and improvement in sperm quality and fertilizing capacity.

Adult↗
PubMed1979

Leydig cell function in streptozotocin-induced diabetic rats.

Streptozotocin diabetic rats were infertile as a result of decreased Leydig cell function of the testes. The major changes found were: decreased number of Leydig cells and their spontaneous secretion of testosterone. No change in the receptors to LH on the Leydig cells was observed. LH was found to be obligatory for the regulation of Leydig cell function and fertility.

Animals↗
PubMed1979

The effect of a combination of prostatic massage and antibiotic plus anticongestive drugs on human semen quality and fertility.

A total of 123 patients suffering from chronic prostatitis and infertility were included in this study. No significant improvement in sperm quality was found following prostatic massage with (90 patients) or without (33) antiobiotic plus anticongestive therapy. There was no apparent change in the relative contribution on the prostate and seminal vesicle of the ejaculate, as judged by the concentration of calcium and fructose. Nor was the pregnancy rate increased. It is concluded that prostatic massage is of little or no therapeutic value in treatment of infertility.

Adult↗
PubMed1978

The cation composition of the seminal plasma and prostatic fluid and its correlation to semen quality.

The concentrations of calcium, magnesium, and zinc were measured by atomic absorption spectrometry. The concentrations of all three cations were found to be strongly correlated with one another and with acidity (pH). Analysis of the relative concentrations in prostatic fluid, split ejaculates, and whole seminal plasma confirmed an almost exclusively prostatic origin of these cations. Semen quality, as judged by motility, vitality, concentration, and morphology of spermatozoa, was inversely related to cation concentrations. Therefore, we recommend adoption of the measurement of seminal divalent cations as part of the routine andrologic examination.

Body Fluids↗
PubMed1978

Effect of diphenylhydantoin on the reproductive function of the male rat.

Male rats were injected with 5, 10, and 20 mg diphenylhydantoin daily for two months and then caged for five days with cyclic females. Thereafter the males underwent necropsy, the organs of the genital tract were examined, and found to be unaffected. Blood testosterone and Leydig cell counts were normal. A significant reduction of fertility was observed which appears to be loss of libido on behavioural grounds. Except for similar behavioural changes described in human epileptics no further reports are available concerning anticonvulsants and fertility. Our findings indicate that there is no reason to suspect that diphenylhydantoin had endocrine-mediated effects on male fertility in the rat.

Animals↗
PubMed1978

Evaluation of semen quality following kallikrein treatment.

30 asthenozoospermic subfertile men were treated parenterally for 30 months with kallikrein. 20 men showed a significant increase in sperm motility, 66% (responders), while the other 10 men, 34% (non-responders), did not respond to this treatment. A striking decrease in sperm concentration (by 32%) was found in most patients. No latent period was found following kallikrein treatment. Thus, semen quality did not differ if examined immediately following the cessation of treatment or a few weeks afterwards. A poor pregnancy rate was recorded, i.e. 20% among the responders and 10% among the non-responders. In conclusion, kallikrein is a useful drug in the treatment of asthenozoospermia only when the sperm concentration is not decreased below the optimal value.

Clinical Trials as Topic↗
PubMed1978

Establishment of an albino sand rat (Psammomys obesus colony and comparison with the natural coloured animal.

The lifespan and fertility of albino sand rats were found to be severely reduced in comparison with a laboratory colony of brown sand rats. The albinos were also much more susceptible to diabetes, as judged by their glucose tolerance. In fact, untreated albinos had a higher incidence of diabetic response than coloured sand rats fed a diabetogenic diet. The albino sand rats reproduced poorly because of a reduction in male fertility. Circulating testosterone levels and seminal vesicle weights were reduced in the albinos. It is speculated that the reduction in reproductive capacity is related to diabetes.

Albinism↗
PubMed1978

Improvement in the fertility of streptozotocin-diabetic male rats following treatment with insulin and human chrionic gonadotropin.

Diabetes was produced in male rats with streptozotocin. Some of them were subsequently treated with exogenous insulin, human chorionic gonadotropin (hCG) or both. The rats were tested six weeks later for fertility, testosterone secretion and spermatogenesis. Diabetes was found to inhibit all three parameters of fertility. Accessory gland atrophy was restodred following the treatment with insulin and much improved with insulin plus hCG. In a diabetic control group on restricted food intake, insulin alone did not significantly improve fertility, whereas hCG enhanced steroidegenesis and spermatogenesis but not fertility. Treatment with both hCG and sinulsin gave the best results.

Animals↗
PubMed1978

Effect of caffeine on sperm penetration rate into cervical mucus in-vitro.

A system for determination of sperm penetration into cervical mucus in a glass capillary tube is described. Repeated counts are made of the number of sperm at fixed horizontal distances from the semen reservoir. The yields indices for total numbers of spermatozoa entering the mucus per unit time and the rate migration of the sperm through the mucus. It was found that the rate of entry was sensitive to changes in motility such as those induced by caffeine, and differences in cervical mucus quality. The system allowed quantitation of these differences.

Caffeine↗
PubMed1977

Immunoreactive insulin in serum and seminal plasma of diabetic and nondiabetic men and its role in the regulation of spermatozoal activity.

Concentrations of immunoreactive insulin (IRI) and, in some cases, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured in serum and seminal plasma (SP). IRI levels were usually higher in SP. They were unaffected by masturbation; circulating testosterone, LH, and FSH levels were also unaffected. The IRI concentration was higher in the second (vesicular) fraction of split ejaculates. Semen quality was unrelated to IRI in SP in normal and diabetic (chlorpropamide-maintained) men. The addition of insulin in vitro to washed spermatozoa from diabetic and nondiabetic men had no effect on oxygen and glucose uptake or on lactate production and spermatozoal motility. Furthermore, administration of L-arginine to infertile men for 3 months (4 gm/day) was followed in four of seven men by significant increases in IRI concentrations in blood and SP. However, neither semen quality nor fertility was improved.

Adult↗