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Spermatogenesis was investigated in the Adriatic sturgeon, Acipenser naccarii, by light and electron microscopy. The testis of the unrestricted type had a germinal compartment composed of lobules containing germ cells and Sertoli cells, and separated by a basal lamina from the interstitial compartment, in which Leydig and myoid cells were detected for the first time in Acipenseridae. Spermatogenesis occurred in spermatocysts produced when Sertoli cells became associated with type A spermatogonia of subsequent generations, which produced a clone of synchronized aligned spermatogonia. In primary spermatocytes at zygo-pachytene stage, the large spherical nucleus contained synaptonemal complexes. The smaller secondary spermatocytes were ovoid with a central round nucleus and scarce cytoplasm. Spermatids were interconnected by cytoplasmic bridges until early spermiogenesis. Chromatin initially condensed as long, twisted, and nonhomogeneous fibers and finally as a compact structure made of thick filaments. Early spermatids showed the flagellum, the primordia of centriole complex and of "implantation fossa," followed by the acrosomal vesicle formed by Golgi complexes and a fibrous body associated to centriole complex. The spermatozoan head had 10 postero-lateral projections and a trapezoidal nucleus, a cylindrical midpiece with six to eight mitochondria, the centriole complex, and a "9 + 2" flagellum with a pair of lateral fins. Three helical endonuclear canals crossed the nucleus from the acrosome base to the implantation fossa; their spiralization and that of chromatin fibers suggest a spiral twisting of the nucleus during spermiogenesis. The Sertoli cells performed phagocytosis of degenerating spermatids and spermatozoa. Significant interindividual differences were detected in most morphological parameters of spermatozoa. Data on spermatogenesis in A. naccarii and morphometric measurements on mature spermatozoa provide information about the reproductive biology of the species useful not only for phylogenetic studies but also for evaluation of sperm quality for artificial reproduction projects and restocking of this and other critically endangered sturgeon species., (© 2018 Wiley Periodicals, Inc.)

Objective: The objective of this study is to evaluate genetic risks already present before pregnancy in a cohort of pregnant women referred for prenatal genetic counseling exclusively for advanced maternal age (AMA)., Method: We retrospectively reviewed the records of 1353 women referred over 1 year (2010) for pre-test genetic counseling with the only indication of AMA at three Italian Clinical Genetic Services., Results: Of the 1353 women fulfilling the inclusion criteria of the study, 87 (6.4%) had cumulatively 94 genetic risk factors not previously identified (one risk factor in 80 patients and two risk factors in seven). Twenty-six risk factors (27.7%) concerned heterogeneous or multifactorial conditions and 68 (72.3%) Mendelian or chromosomal disorders and consanguinity.In nine out of these 87 women, the estimated risk for the offspring of a genetic disease or a significant structural anomaly was >5%. Additional testing according to the identified risks was performed in 36 of these 87 women/families., Conclusions: The proportion of cases with additional risk factors is smaller than reported in previous studies, but it remains substantial and confirms the need for strategies to increase awareness of the public and health professionals responsible for the care of women in childbearing age.