Zidovudine inhibits telomere elongation, increases the transposable element LINE-1 copy number and compromises mouse embryo development.

Purpose: Millions of pregnant, HIV-infected women take reverse transcriptase inhibitors, such as zidovudine (azidothymidine or AZT), during pregnancy. Reverse transcription plays important roles in early development, including regulation of telomere length (TL) and activity of transposable elements (TE). So we evaluated the effects of AZT on embryo development, TL, and copy number of an active TE, Long Interspersed Nuclear Element 1 (LINE-1), during early development in a murine model.

Impaired reproductive function and fertility preservation in a woman with a dyskeratosis congenita.

Purpose: To determine the impact of accelerated telomere shortening on the fertility parameters and treatment outcomes of a woman with dyskeratosis congenita (DKC).

Methods: A case study of the clinical data, blood, discarded oocytes, and arrested embryos of a woman with DKC and donated cryopreserved embryos from unaffected patients. Mean telomere length in blood cells was analyzed by flow cytometry-fluorescence in situ hybridization (flow-FISH) and qPCR.

Telomere Length and Telomerase Activity in Immature Oocytes and Cumulus Cells of Women with Polycystic Ovary Syndrome.

Metaphase II oocytes (MII) from polycystic ovary syndrome (PCOS) frequently have impaired oocyte competence. Since telomere maintenance is important for folliculogenesis, oocyte maturation, and early embryonic development, we sought to verify the implications of PCOS on telomere length and telomerase activity in immature oocytes and cumulus cells. 43 PCOS and 67 control women were included, and anthropometric, biochemical, and hormonal characteristics were evaluated.

Endometrium-free uterine closure technique and abnormal placental implantation in subsequent pregnancies.

Background: Abnormal placentation can result in massive hemorrhage, which is the leading cause of severe maternal morbidities and mortality in its management. Over the past 50 years, the incidence of placenta previa (PP), abnormal implantation of the placenta, and cesarean scar pregnancy have continued to rise. This coincides with the well-documented parallel rise in the rate of cesarean deliveries, the performance of multiple repeat cesarean deliveries and the adoption of newer uterine closure techniques.

Amyloid-like substance in mice and human oocytes and embryos.

Purpose: To identify and characterize amyloid-like substance (ALS) in human and mouse oocytes and preimplantation embryos.

Methods: An experimental prospective pilot study. A total of 252 mouse oocytes and preimplantation embryos and 50 immature and in vitro matured human oocytes and parthenogenetic human embryos, from 11 consenting fertility patients, ages 18-45.

[Chagas' disease seroprevalence among school-age children in Espírito Santo State, Brazil, 1999-2000].

Although the Brazilian State of Espírito Santo is not considered endemic for Chagas' disease, the sylvatic triatomines occurring there frequently invade houses, increasing the chances of Trypanosoma cruzi transmission to man. The epidemiological pattern of the disease in Espírito Santo was evaluated by a serological survey of 5,243 schoolchildren ages 7 to 14 years, residents of 17 municipalities. Indirect immunofluorescence, indirect hemagglutination, and immunoenzymatic (ELISA) tests were positive in only one person, representing only 0.