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A M Jequier

Publications and source records attributed to A M Jequier.

62 records · Page 4Linked to original sources

The isolation of a possible antagglutinin from human semen.

A substance, proteinaceous in nature, with an anti-agglutinic action on clumped sperm has been extracted from human semen. It appears to exist in two forms: an active reduced form and an inactive oxidised form. The protein was extracted from oxidised seminal plasma by salting with saturated ammonium sulphate. The extract was purified by preferential adsorption on a calcium carbonate column, the eluate being collected as fractions. The antagglutinin gave an extinction curve, as determined by ultraviolet spectrophotometry, similar to that as reported for the bull. Extraction recoveries, from semen stored frozen at different temperatures, indicate that the substance is possibly enzyme labile. An effect of the antagglutinin on clumped human sperm is illustrated.

Agglutinins↗

Cyproterone acetate and a small dose of oestrogen in the pre-operative management of male transsexuals. A report of three cases.

The pre-operative treatment of three adult male transsexuals with the anti-androgen and progestogenic compound cyproterone acetate is reported. When used in combination with cyproterone acetate, only a very small dose of oestrogen is needed to induce feminisation. The effect of this treatment on both testicular and epididymal function is described.

Adult↗

A test of the human sperm acrosome reaction following ionophore challenge. Relationship to fertility and other seminal parameters.

Acrosome reaction capacity was tested on semen samples from 53 fertile and 26 subfertile men. Preparations were divided into two aliquots after 3 or 24 hours of culture. One aliquot received 10 mumol/L calcium ionophore A23187 in dimethyl sulfoxide (DMSO) and the other received DMSO alone. Acrosome reactions were scored on ethanol-permeabilized smears using fluorescein isothiocyanate (FITC)-conjugated Pisum sativum lectin. The following factors were analyzed: the spontaneous reaction rates (control); induced reaction rates (ionophore-challenged); and the difference between the two, being the proportion of spermatozoa in the population capable of reacting in response to calcium influx (acrosome reaction to ionophore challenge [ARIC]). While spontaneous reactions bore no relation to fertility, induced reactions and ARICs were significantly reduced or absent in subfertile men, indicating acrosomal dysfunction as a likely cause of fertilization failure. The test was shown to have a predictive value for fertility comparable to that of the hamster ovum sperm penetration assay and to be a simple and cost-effective addition to existing semenology.

Acrosome↗

Congenital absence of the vasa deferentia presenting with infertility.

Congenital absence of both vasa deferentia is not an infrequent cause of sterility. Between April 1975 and December 1981, 11 men out of a total of 749 presenting with infertility were diagnosed as having congenital absence of both vasa deferentia. Subsequent clinical investigations showed that FSH levels were within the normal range (2-10 mIU/ml), blood karyotype (XY) was normal, and testicular histology demonstrated normal spermatogenesis. Seminal volume was markedly reduced in nine patients (range 0.25-1.0 ml). In three out of four patients tested, seminal fructose was found to be completely absent. Of the 11 patients, eight subsequently had exploratory surgery. In four men, the whole epididymis was present on both sides, while the other four had varying parts of one or both epididymides absent. In six of the eight patients explored surgically, no trace of the vasa deferentia could be found, while one other patient had thin fibrous cords in the anatomical site of the vasa deferentia. A possible cause for the abnormality and the importance of seminal fructose estimation are discussed.

Epididymis↗