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F Porcelli

Publications and source records attributed to F Porcelli.

At least 37 records · Page 2Linked to original sources
PubMed1988

Effects of deep freezing on the energy metabolism of bovine spermatozoa during in vitro capacitation: A cytochemical approach.

In order to study the effects of deep freezing on the energy metabolism of bovine spermatozoa, a cytochemical quantitative study was carried out by a microdensitometric method on cytochrome oxidase and lactate dehydrogenase (LDH) activities. These were evaluated in situ on individual frozen-thawed bull spermatozoa collected at different times during in vitro capacitation. The results showed that in bull spermatozoa both the initiation of motility and capacity to fertilize eggs were associated with the anaerobic rather than aerobic glycolysis. The freezing-thawing processes and storage in liquid nitrogen induced a general enhancement of both the enzymatic activities examined. The high ionic strength treatment gave rise to a significant but reversible decrease in both the cytochrome oxidase and LDH activities in the fresh as well as in the frozen-stored sperm. The findings, based on cytochemical observations of energy metabolism of spermatozoa and evaluated during in vitro capacitation, suggest that the respiration and the anaerobic glycolysis of spermatozoa seem to be slightly impaired by the freezing-thawing and storage processes.

Journal Article↗
PubMed1987

Cytochemical study on human spermatozoa metabolism during in vitro capacitation.

In eutherian mammalian spermatozoa the capacitation is coupled to a specific type of metabolism, that is glycolysis or oxidative respiration. A cytochemical study was carried out on cytochrome oxidase and lactate dehydrogenase in human spermatozoa collected at different times during in vitro capacitation. Human spermatozoa were incubated in Biggers, Whitten and Wittingham's medium supplemented with 15% heat-inactivated human serum. Both histoenzymological reactions based on oxidative polymerization of diaminobenzidine (cytochrome oxidase) or on tetrazolium salts reduction (lactate dehydrogenase) can be quantitated and have been evaluated by microdensitometric method (Vickers M85). The results suggest that human spermatozoa depend almost quite on the anaerobic glycolysis during in vitro capacitation.

Electron Transport Complex IV↗
PubMed1985

Pseudo-precocious puberty associated with mediastinal teratoma and polycystic ovary.

A 10-month-old girl with sexual precocity of recent onset was found to have elevated levels of estrogens, progesterone and androgen precursors, associated with a polycystic left ovary. After ovariectomy, estrogen and androgen levels were normal, and the clinical symptoms began to regress. A few months later, a huge mediastinal mass was unexpectedly discovered. Removal of the mass, identified later as a benign teratoma, was followed by the total normalization of the clinical and hormonal findings. The patient's pseudo-precocious puberty might have been due to an ovarian overproduction of estroprogestins and androgens, associated with a paraneoplastic production of progesterone, or in theory, it might have been due to a gonadotropin-like stimulation of the ovary by the teratoma.

Chorionic Gonadotropin↗
PubMed1984

Clinical applications of the rapid high-performance liquid chromatographic determination of serum cortisol.

We report a rapid and specific analytical method for the measurement of serum cortisol by reversed-phase high-performance liquid chromatography (HPLC). The method allows the diagnostic measurement of cortisol in emergency clinical circumstances of glucocorticoid deficiency or excess. Results obtained by HPLC are comparable to those by radioimmunoassay. The lower limit of sensitivity is 6 ng cortisol per ml of serum.

Chromatography, High Pressure Liquid↗
PubMed1982

Cytochemical behavior of rabbit spermatozoa chromatin in male and female genital tracts.

Cytochemical parameters have been used to investigate the physicochemical modifications of rabbit spermatozoa chromatin in the male and female genital tracts. Analysis of these parameters revealed the progressive condensation of the DNA-protein complex along the male genital tract and its progressive decondensation along the female genital tract.

Animals↗
PubMed1980

Human round-headed spermatozoa: a quantitative and qualitative cytochemical study on chromatin.

A quantitative and qualitative cytochemical study on human round-headed spermatozoa chromatin(Feulgen-DNA content, basic clear protein content, acid-resistance degree of DNP) was carried out. Feulgen-DNA and basic nuclear protein contents showed in different nuclear classes of various sizes within the whole population a variability of behaviour. Our data suggest the occurrence of meiotic malsegregation events followed by production of aneuploid gametes whose chromatin appears to be more compacted than controls.

Adult↗
PubMed1979

Histochemical studies on the autonomic innervation of the femoral artery and vein.

The innervation of the femoral artery and vein in the dog was studied using: a) glyoxylic acid fluorescence (for the histochemical localization of adrenergic nerve fibers); b) acetylcholinesterase (for the histochemical localization of cholinergic nerve fibers). -Andrenergic nerve fibers and related terminals in both vessels are confined to the adventitial-medial transitional zone and the outer layers of the media. Acetylcholinesterase containing nerve fibers are localized in the adventitial-medial transitional zone of the femoral artery. These findings may indicate the presence of a cholinergic vasodilatator system in the control of the circulation in the femoral artery.

Acetylcholinesterase↗
PubMed1979

Cholinergic nerves in blood vessels of the female reproductive system.

Cholinergic innervation of the blood vessels of the female reproductive system was investigated in human by the cholinesterase method. The following results were obtained: 1. The uterine and vaginal arteries are provided with a rich cholinergic innervation. 2. The ovarian, tubaric and ovarian-uterine artery are poorly innervated. 3. The ovarian and uterine vein are not provided with a cholinergic innervation.

Acetylcholinesterase↗
PubMed1979

Tests to localize free proteolytic enzymes in vivo by 14C-cysteine-aprotinin.

Aprotinin, a polyvalent protease inhibitor from bovine organs, has been labelled with 14C-cysteine in 6 M urea to produce a radioactive conjugate, without effect on the inhibitor activity. 138x10(3) dpm of radioactive product, containing 5 mg of protein (20.000 kal. inhibitor units) in 5 ml of Locke's solution were perfused in anesthetized rabbits via ascending aorta. Then the anesthetized rabbit was killed and specimens of some organs were admitted to autoradiographic analysis. Small intestine, ischiatic nerve and testis have been the most rich radiolabelled organs (+++). In kidney, stomach, large intestine, liver and eye the radiolabelled aprotinin was found in fair amounts (++); while in pancreas, spleen, spinal cord, brain, cava vein and aorta of rabbit the 14C-cysteine-Aprotinin was practically undetectable by autoradiography.

Animals↗
PubMed1979

Leucine aminopeptidase (LAP) activity and sexual dimorphism in rat exorbital lacrimal gland.

Leucine amonopeptidase (LAP) activity was histochemically studied in the rat exorbital lacrimal gland. The enzyme is present in the secreting cells of both male and female prepuberal rats, in vivo and in monolayer cultures, while in the adult rat it is demonstrable only in the female. Furthermore, LAP is influenced by the sex hormones, disappearing in the female gland after testosterone treatment and appearing in the adult male gland after administration of estradiol or cyproterone acetate. These results show that the behaviour of LAP can be considered as another character of sexual dimorphism of the rat exorbital gland. Furthermore, our findings, showing an inverse relationship between LAP activity and the PAS positivity of the secretion products, suggest the hypothesis that the presence of this exopeptidase could induce qualitative modifications of one or more secreted glycoprotein.

Aging↗
PubMed1978

Cholinergic nerves in the thyroid gland.

The cholinergic innervation of the thyroid gland has been studied in the human. AChE positive nerve fibers are localized in the wall of the thyroid artery, arranged in two plexuses, a superficial (adventitial) and a deep one (medial). The glandular tissue is provided with cholinergic nerve fibers, localized between and around thyroid follicles. The present results suggest that the endocrine activity of the thyroid gland is also under the control of the autonomic nervous system.

Acetylcholinesterase↗
PubMed1977

Effect of antiblastokinin on rabbit pregnancy.

On different days following coitus, i.e., during the first stages of pregnancy, adult female rabbits were treated with antiblastokinin obtained from a chicken. A high prenatal mortality was observed and a reduction of the weight in the stillborn of the rabbits treated. The antiblastokinin produces evident biological effect about the 4th day following coitus, during the period of maximum production of blastokinin by the endometrium in vivo.

Animals↗