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J F Guerin

Publications and source records attributed to J F Guerin.

At least 55 records · Page 3Linked to original sources
PubMed1981

Enzymes in the seminal plasma from azoospermic men: correlation with the origin of their azoospermia.

Semi-quantitative estimations of the activities of 65 enzymes were studied for cases of azoospermia in an attempt to correlate the seminal enzyme profile with the origin of the azoospermia. One single enzyme--alpha-glucosidase--showed variation. All other specificities tested gave identical results for all the azoospermic samples and for normal controls. The alpha-glucosidase activity that is present in normal semen was absent from samples from patients with azoospermia associated with a complete obstruction of the genital tract, and also from all semen samples from vasectomized subjects. This enzyme appears to be secreted by the epididymis, and the activity present in azoospermic semen can provide information concerning the origin of the azoospermia and the functional state of the epididymis. Positive but reduced alpha-glucosidase activity appears to be frequently associated with inflammatory disease. The consequences of these findings are discussed.

Follicle Stimulating Hormone↗
PubMed1981

[Congenital or acquired obstructions of the human epididymis: study of the motility of the spermatozoa above the obstruction].

Azoospermia is frequently due to an obstruction of genital pathways. In this work, concerning 22 patients submitted to surgical investigation for sterility, we made a systematic histological investigation of the lesions, and we studied the motility of epididymal spermatozoa. We observed with an unexpected frequency abnormalities of junctions either between seminiferous tubules and efferents ducts - leading to disappearance of rete testis - or between efferent ducts and epididymis. In each case a fibrosis of the epididymis was discovered, the consequence was either an interruption or, more frequently a simple narrowing of the lumen of the epididymal duct. The presence of spermiophages which destroyed all spermatozoa, was also systematically observed. The origin of the lesions (congenital, inflammatory, ischemic... ) could not be determined by simple histological study. Motility of spermatozoa was generally observed in the initial portion of the epididymal duct, but motile spermatozoa were sometimes still observed in the efferent tubules. Motility could be initiated by caffeine while other compounds as albumin, seminal plasma and different organic substrates, had no effects.

Epididymis↗
PubMed1980

Individual characteristics of human spermatozoa.

We have investigated the variability of some characteristics of a sperm sample in 18 young volunteers in good health who were examined twice per month over a period of two years, and in about one hundred men undergoing treatment for sterility and for whom more than 4 spermiograms had been established during the past three years. The results of statistical analysis indicate that the most characteristic individual feature is the concentration of spermatozoa.

Humans↗
PubMed1980

[Energy metabolism of spermatozoa: present status of the subject].

The energetic metabolism of the human sperm is characterized by the predominant importance of glycolytic pathway, with the probable participation of the pentose shunt. The participation of the aerobic pathway is very small since the oxidative phosphorylation seems to be partially uncoupled at time of ejaculation. There is no correlation between the respiratory activity and the mobility of the sperm. The effects of several physicochemical conditions were studied, indicating that the spermatozoon is indeed very resistant to variations of its environment. Seminal plasma seems to be a rather unsuitable medium for investigations of the glycolytic pathway, with the probable participation of the pentose shunt.

Adenosine Triphosphate↗
PubMed1979

Effects of ions and K+:Na+ ratio on motility and oxygen consumption of human spermatozoa.

Variations in the osmolarity of the medium altered motility, velocity, and oxygen consumption of human spermatozoa. Variations in the K+:Na+ ratio also altered their motility and velocity. These alterations, which reflect both the composition of the medium and individual characteristics of the donor, are discussed in relation to the diversity of milieu through which the sperm are transported.

Humans↗
PubMed1979

Enzyme comparative study of spermatozoa and seminal plasma in normal and subfertile man.

A semiquantitative colorimetric micromethod (APIZYM) was used to study the enzyme profiles of seminal plasma and of spermatozoa. Reactions with 65 different substrates are simultaneously tested in a single specimen. These substrates (principally naphtolic) allow the detection of hydrolytic enzymes (esterases, phosphatases, and peptidases) and of dehydrogenases potentially involved in sperm metabolism and in the process of fertilization. The usual sperm enzymes were regularly observed: C3-C4 esterases, amino acid arylamidases, acrosine, phosphatases, glutamyl transpeptidase, and various osidases. Among the dehydrogenases we observed a striking predominance of the enzymes of the hexose monophosphate shunt and of LDH. Seminal plasma has an enzyme pattern very similar to that of spermatozoa except for the absence of acrosine and of some dehydrogenases. This unexpected similarity is discussed. The gametes from subfertile donors do not at first sight differ in their enzyme pattern from those from fertile donors. Moreover, we found no marked differences between zymograms of seminal plasma from normal, subfertile, or even azoospermic patients. Deep freezing does not modify the hydrolytic enzymes of human sperm either quantitatively of qualitatively, but the dehydrogenases of the hexose monophosphate shunt are adversely affected (60% loss of activity for G 6 PDH, and 30% for 6 PGDH); LDH is not affected. The consequences on fertilizing capacity of frozen semen are discussed.

Humans↗
PubMed1976

[Modifications of motility and respiratory activity of human spermatozoa following congelation in liquid nitrogen].

By using a polarographic technique it has been noticed that the respiratory activity of human sperms was increased after addition of cryoprotector medium to semen. But this activity was markedly reduced after freezing in liquid nitrogen. We suppose that freezing causes a damage of some metabolic structures of cells which affects more severely their respiratory activity than their motility.

Cell Survival↗
PubMed1976

[Influence of temperature on the motility of human spermatozoa].

The mean swimming speed of a suspension of human sperms has been estimated by applying a kinetic theory and using an image analysing computer. This technique allowed the study of the evolution of motility in terms of temperature: the global swimming speed significantly increases from 22 degree C to 31 degrees C, and then remains rather constant. However the percentage increases are very varying according to samples.

Humans↗
PubMedDate not supplied

Alpha-glucosidase as a specific epididymal enzyme marker. Its validity for the etiologic diagnosis of azoospermia.

Azoospermic semen was obtained from 39 vasectomized men and 93 patients consulting for infertility. The latter underwent bioclinical investigations including measurement of plasma FSH and testicular biopsies. Carnitine content and alpha-glucosidase activity in semen samples were measured. The activity of alpha-glucosidase was determined systematically by a semiquantitative microtechnique and was verified by a spectrophotometric assay. A positive correlation was observed between carnitine and alpha-glucosidase activity. Both parameters were severely diminished in semen from the vasectomized men and the patients suffering from a complete obstruction of the genital tract. Enzyme activity was the most discriminant parameter in terms of sensitivity and specificity. The measurement of alpha-glucosidase in semen is a simple and sensitive method for determining the origin of azoospermia when used in conjunction with assays for plasma FSH.

Carnitine↗
PubMedDate not supplied

Evaluation of sperm motility by optical diffractometry of spermatograms.

Evaluation of sperm motility based on analysis of spermatograms by optical diffractometry was performed. Spermatograms are defined as images of sperm tracks obtained on microphotographs by dark field illumination with long exposure time. Single track analysis proved that the details concerning single tracks are "seen" and recognized by the technique of optical diffractometry. Normal "linear", as well as abnormal "irregular", including "circular", tracks were numerically described. Multitrack analysis: The general pattern of all tracks contained in particular spermatograms derived from two groups of semen classified by hospital laboratory as "high" (control) and "low" ("mediocre") motility of spermatozoa, respectively, were analysed by optical diffractometry. The hospital laboratory was asked to provide for diffractometric analysis samples of the "mediocre" semens of quality similar enough to the "control" ones what concerns the percentage of motile spermatozoa (40 percent) and spermatozoan concentration. Diffraction patterns of 102 spermatograms of control sperm and of 103 spermatograms of sperm qualified as "mediocre" by subjective microscopic evaluation of sperm motility, were analysed and compared. Using discriminant analysis based on parameters describing radial distribution of light intensity in diffraction patterns of control and "mediocre" spermatograms, it was possible to classify correctly 71 cases as high motility sperms out of 102 spermatograms evaluated beforehand by hospital laboratory criteria as control ones. In the group of 103 spermatograms classified as "mediocre" sperms by hospital laboratory criteria 69 cases were correctly recognized as "mediocre" by diffractometric analysis. The overlapping of the analysed two groups of sperm by 30 percent might be explained by the fact that in the control spermatograms many trajectories are formed by inefficient, slow moving spermatozoa.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMedDate not supplied

Effect of spermatozoa selection on a simplified Percoll gradient in case of asthenozoospermia.

Two methods for preparing semen (Swim-up migration and centrifugation on a two step density Percoll gradient) were tested in 21 cases of asthenozoospermia (motility less than 30%). The parameters of sperm movement were studied through automated videomicrographic analysis. In 9 cases out of 21 swim-up migration failed while centrifugation on a Percoll gradient failed in only 1 case out of 21.

Cell Separation↗