Localisation of two classes of acetylcholine receptor-like molecules in sperms of different animal species.

The distribution of different classes of acetylcholine (ACh) receptor-like molecules in sperms of different invertebrate and vertebrate species is described. ACh receptor molecules belong to one of two classes: muscarinic receptors (mAChRs), associated with signal transduction mechanisms in the inner domain of the cell, and nicotinic receptors (nAChRs), capable of opening Na+ channels when activated by the ligand. Molecules immunologically related to mAChRs and to ACh can be identified by specific antibodies, and revealed by immunofluorescent or immunogold staining; the nicotinic receptor-like molecules are localised as curare-sensitive affinity sites for alpha-bungarotoxin.

Notulae seminologicae. 5. Mathematical evaluation of interdependent submicroscopic sperm alterations.

This paper concerns the mathematical evaluation of sperm quality as examined by electron microscopy. Proceeding with a Bayesian technique, we have developed a formula considering all statistical possibilities for defects of the examined sperm to be present in a sperm cell, the total number of affected spermatozoa, and, as consequence, that of sperm devoid of defects, also considering the probability of association characteristics of some of them. The formula has been studied in three applications.

Notulae seminologicae. 4. Mathematical evaluation of submicroscopical alterations in spermatozoa of sterile men with varicocele.

In this paper the mathematical formula recently proposed by Baccetti & Mirolli in this journal is used for the quantitative electron microscopical evaluation of six submicroscopical defects frequently present in the spermatozoa ejaculated by patients affected by various degrees of varicocele. All these characteristics are independent from each other and are in some way related to imperfect sperm maturation. They concern the shape and position of the acrosome, the status of the chromatin, of the mitochondria, of the axoneme, the individuality of the cell.

HIV-particles in spermatozoa of patients with AIDS and their transfer into the oocyte.

By immunocytochemistry and in situ hybridization at the electron microscopy level, and by the PCR technique, we have shown that HIV-1 binds and enters normal sperm; that viral particles, their antigens, and nucleic acid are present in sperm from HIV-1 infected men; and that such sperm can transfer HIV-1 like particles to normal human oocytes. We also present evidence that a galactosylceramide-like compound is present on the sperm membrane and could function as an alternative receptor for HIV.

Notulae seminologicae. 2. The 'short tail' and 'stump' defect in human spermatozoa.

In this note several cases of stunted tails involving the total sperm population in sterile humans are described. Half of the cases are classified as 'short tailed' spermatozoa, the other half as 'stump defect' previously described in bulls. Both defects are referred in details at electron microscopical level.