Biomedical subjects
Publications and source records attributed to A Clavert.
A method is reported for collection of sperm by electrostimulation or prostatic massage in order to carry out artificial in utero insemination in Lemur fulvus mayottensis. Using fresh sperm, one success out of 7 attempts was obtained, although it was achieved with a vesiculectomized male.
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Injection of solutions of E. coli leads to vesiculitis which regresses spontaneously, and to interstitial prostatitis. Castration preceding experimental injection of a bacterial solution modifies the progression of the vesiculitis which then becomes chronic. Infection does not seem to diffuse via the lympathic system, even after castration.
Treatment with V.1326 in the rat induces an increase in prostatic secretion. In men with insufficient prostatic secretion, this treatment also induces an increased secretion.
When soluble seminal proteins from different animal species are studied by cellulose acetate electrophoresis, important differences can be observed. These differences may be related to the type of coitus and the storage and migration of spermatozoa in the female genital tract. Seminal fluid can play a role in spermatozoal maturation by affecting the distribution of the surface charge of spermatozoal membranes.
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Glucose and fructose levels were determined enzymatically in liquefied human seminal plasma (whole or collected in three fractions) and in preparations obtained by DEAE ion-exchange chromatography on whole seminal plasma. When these secretions or DEAE-extracted preparations were overloaded with fructose, the level of glucose increased. This increase is greater in fraction I of split ejaculates than in fractions II and III, and is greater in solutions containing elements of prostatic secretion obtained chromatographically than in whole seminal plasma. Using increasing quantities of fructose in the overloading test, glucose levels reached a maximum, suggesting that the process of conversion of fructose into glucose appears to be related to an enzymatic process. Other experiments suggest that the sperm-free fraction I of split ejaculates and compounds obtained from seminal plasma by ion-exchange chromatography contain enzymes of prostatic origin that are involved in the conversion of fructose to glucose.
The efficiency of Pygenum africanum treatment was tested on a population where the acid phosphatase activity was shown to be reduced at two successive examinations. The treatment caused an increase in acid phosphatase activity and total protein secretion. However, the fact that the men who had IgA present in their ejaculate reacted more favorably to the treatment shows that Pygenum africanum is more efficient in cases where there is no prostate gland inflammation.
The injection of E. Coli into the tail of the epididymis in the rat caused epididymitis. In 20% of the cases, the inflammation is spread through the lymphatic system to the testis. The germinal cells are destroyed in 50% of the cases by the second day, and are not reestablished for several months. Signs of testicular inflammation are not found. The destruction seems to be caused by E. Coli toxins, as shown by injections of killed bacteria.
The prostatic fraction of seminal plasma contains components that are involved in the process of transforming fructose into glucose. If a positive correlation can be found between the slope of the decrease of fructose (estimated to be between 30 minutes and 5 hours) and the sperm count, with at the same time the maintenance of a relatively constant glucose level, then we have been able to demonstrate that glucose is more efficient than fructose to keep spermatozoa mobile. The enzyme process involved in transforming fructose into glucose may thus act to maintain definite glyspermia with a maximum value of 1.8 g/l. Aspermia in some circumstances then can be related to the absence or poor function of the transformation process and thus with the absence or decrease in prostatic secretion.
Pathological seminal liquids were studied by using cellulose acetate electrophoresis as well as biochemical doses of proteins, acid phosphatases, reducing sugars, and zinc. It was also possible to show the frequent total absences of vesicular secretion, less frequent than prostatic secretion and less than the two at the same time. It was also shown that reductions were more frequent in prostatic secretion than in vesicular secretion. This method may also be a valuable assistance in the diagnosis of certain urogenital infections. The dissociation between prostatic secretions of acid phosphatases and zinc may lead to the diagnosis of the infection in the posterior or lateral lobes of the prostate.
The study of spermiograms, conducted on patients consulting for sterility, showed relationships between motility and other variable factors of the sperm. Testicular and prostatic factors are involved in immediate asthenospermia, whereas factors are involved in secondary asthenospermia.
Following hemicastration, the epididymis on the non-operated side progressively hypertrophies and remains in this state for an unlimited length of time. This modification is due to an increase in androgens from the remaining testicle via lymphatics and/or lumen. This increase in weight seems to be due to an increase of testicular content by activation of in situ cells.
By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man.
An orderly pattern of cell death accompanies growth of retinal ganglion cell axons through the optic stalk of the chick embryo. In order to determine if the cell death process in this anlage is preprogrammed at earlier stages or if other factors play a role, we cultured optic stalk primordia at a stage prior to retinal differentiation, either alone or in the presence of head or limb bud mesenchyme. When optic stalk was cultured alone, many cells differentiated into neurons. However, when mesenchyme cells of either head or limb bud origin were combined with the stalk, the stalk cells either degenerated, were unrecognizable in the mesenchyme mass, or retained their epithelial arrangement and became pigmented. Mesenchyme and/or neural crest which normally migrate around the stalk at the same time that ganglion cell axons penetrate this structure may therefore be involved in some aspect of the cell death process. Since many optic stalk cells in vitro differentiate into neurons, these cells may represent the population of cells which in situ would normally die.
The pampiniform system plays an important role in the thermoregulation and the concentration of hormones in the testicle. The study of the vascularization of the testicle and of the epididymis shows an independent vascularity in the case of the rabbit. The arteries of the head of the epididymis leave the spermatic artery before the establishment of the particular relationships which exist between the testicular artery and the pampiniform system. Temperature monitoring shows no difference between these two organs. It appears in this case that the thermo regulation is achieved essentially by the scrotum. It is not possible to say if any hormonal exchange takes place between the testicle and the epididymis.