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Biomedical subjects

G Frajese

Publications and source records attributed to G Frajese.

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

Oxygen consumption of human seminal plasma: relationships with semen characteristics.

It is possible to determine oxygen consumption rate in human seminal plasma through voltammetric measurements. The seminal fluid of the sterile patients in this investigation was characterized by an anomalous sperm motility. Also studied was a control group of proven fertile subjects. The mean value of oxygen consumption resulted greater in the reduced sperm motility group than in the control group. The polyaminoxidase system is the most important factor in oxygen consumption in seminal plasma; however, it is likely that the high toxicity of polyamine degradation products is the cause of reduced and/or anomalous sperm motility in some seminal fluids.

Adult↗
PubMed1980

Preparation of pure fractions of human sperm membranes.

A procedure to isolate plasmalemma and outer acrosomal membranes from human spermatozoa provides reasonably purified fractions. Based on the shaking of samples in conditions that are not damaging for spermatozoa, this procedure excludes the use of chemical reagents or other chemicophysical methods harmful to sperm structure. The isolation of fractions is carried out by means of ultracentrifugation. The efficacy of the methodology has been verified by electron microscopy and by enzymological assays. The proposed method is easy to perform and gives good recoveries.

Acrosome↗
PubMed1980

Prolactin release in polycystic ovary.

Ten normoprolactinemic and 10 hyperprolactinemic patients, all with polycystic ovary syndrome (PCO), were subjected to prolactin (PRL) stimulatory tests with thyrotropin-releasing hormone (TRH), 200 microgram intravenously, and haloperidol (a dopamine-blocking agent), 1 mg intramuscularly. The results were compared with those of 8 women with idiopathic hyperprolactinemia and 10 normal female volunteers. Distinctive features of PCO were elevated plasma concentrations of luteinizing hormone, estrone, and testosterone in the presence of normal estradiol, whereas in idiopathic hyperprolactinemia estradiol was reduced. Both groups of patients with PCO exhibited responses to TRH and haloperidol significantly higher than the controls (P less than .001), whereas only the hyperprolactinemic PCO patients reacted with an excessive PRL discharge (P less than .001). As expected, the response to both secretagogue agents was blunted in patients with idiopathic hyperprolactinemia. The present report discusses the possible implication of estrogen and the dopaminergic system in the mechanisms leading to hyperprolactinemia and enhanced PRL release in PCO.

Estrogens↗
PubMed1979

Free amino acids in semen: measurement and significance in normal and oligozoospermic men.

Measurement of free amino acids in seminal plasma from fertile and infertile oligozoospermic subjects revealed a quantitative reduction of these molecules in infertile patients. Study of the effect of acidic media on seminal plasma appears to suggest the primary role of free amino acids in the "protection" of spermatozoa in the vagina, and the failure of sperm progression in the female genital tract may be due to a decrease of these molecules in semen of infertile patients.

Adult↗
PubMed1978

Influence of hyperprolactinaemia due to metoclopramide on gonadal function in men.

Five clinically normal male volunteers were given metoclopramide, 10 mg t.d.s. for 6 weeks. During treatment prolactin concentrations were elevated (over 50 ng/ml) in all. LH, FSH, testosterone and cortisol concentrations were not altered. No change was observed in LH or FSH responses to LHRH testing 4 weeks after the beginning of therapy, compared with pre-treatment values. A reduction in seminal volume and total sperm count were observed in each subject. Four noticed a decrease in libido and three lost spontaneous erections. While the metoclopramide-induced hyperprolactinaemia could be the cause of the observed changes in semen and erectile activity, it is possible that this dopamine receptor blocking drug might directly affect central or peripheral mechanism of erection, the testes or accessory organs.

Adult↗
PubMed1978

Arginine evaluation to verify sperm maturation in man.

A modified version of Sakaguchi's histochemical reaction is proposed for the evaluation of arginine content in spermatozoa as an index of sperm maturation. Results obtained with this procedure, compared with DNA and basic nuclear proteins determinations in the sperm cells from normal subjects and from patients with oligospermia, appear to confirm the usefulness of this technique.

Adult↗
PubMed1976

High deoxyribonucleic acid content of spermatozoa from infertile, oligospermic human males.

A study has been carried out, by means of an indole microchemical technique, of the DNA content of spermatozoa from a group of 13 normal subjects and 13 patients affected by infertility, characterized by oligospermia with a clinical, hormonal, and testicular picture peculiar to "idiopathic spermatidic arrest." The DNA content of spermatozoa from the infertile, oligospermic patients was nearly double that of normal subjects. This finding can be explained tentatively on the basis of genetic and/or cytologic events occurring during meiosis.

Adult↗
PubMed1976

Histones instead of protamines in terminal germ cells of infertile, oligospermic men.

A study was carried out, by means of polyacrylamide gel electrophoresis, of the nucleoproteins of spermatozoa from infertile, oligospermic patients affected by partial idiopathic spermatidic arrest. Results in a normal group of men, in agreement with previous reports, showed the presence of protamines in mature spermatozoa. Data relative to nucleoproteins in "spermatozoa" from the infertile patients showed that, in these cells, no protamines were detectable, but histones exclusively. These findings suggest that in our patients a maturational defect of spermatogenesis exists both at the meiotic level (a DNA content double that of spermatozoa) and during spermatidic maturation (no substitution of histones by protamines). Therefore, the nuclear maturation of these terminal germ cells is that typical of that of primary spermatocytes.

Adult↗