Differentiation of the genital apparatus in juvenile echinoids (Paracentrotus lividus)

info:eu-repo/semantics/published

Hardening of zona pellucida of mouse oocytes and embryos in vivo and in vitro

Objective - To evaluate the effect of in vitro culture on zona pellucida resistance in mouse oocytes and embryos. Method-Zona pellucida resistance was assessed by comparing duration of zona lysis in the presence of alpha- chymotrypsin. The effects of artificial or physiological conditions of development were evaluated by comparing embryos in vitro with those left to reach the same stage of development in vivo. Results - The time required for zona lysis of oocytes increased after 2, 9.4, and 48 hours in vitro (P < .001). The same observation holds true for oocytes left in vivo during 24 hours. Fertilization both in vivo and in vitro induced a major increase in zona resistance. At the two-cell stage, in vitro culture did not harden the zona pellucida. At the morula stage and beyond, enzymatic lysis was slightly longer in vitro as compared to that of similar stages recovered from the genital tract. Conclusions - Our data indicate that in vitro culture conditions do not modify zona hardening in oocytes and only slightly increased zona resistance from the morula stage on.

Syndrome d'immunodéficience acquise (AIDS) révélé par un herpes génital sévère. A propos de deux cas.

The authors present 2 cases of AIDS revealed by severe recurrent genital herpes simplex. The patients are 2 young, previously healthy, African women without histories of homosexuality or drug abuse. The first patient died after 5 months of follow-up (post mortem findings: viral bronchopneumonia with positive cultures for herpes and cytomegalovirus (CMV), viral colitis due to CMV). The second patient survived. She has been treated, during the last 11 months, for filariasis, buccal and vaginal candidiasis and cerebral toxoplasmosis.