Considerable attention has currently been focused on bisphenol A (BPA), an environmental endocrine disrupting chemical that has oestrogenic activity. In vitro and in vivo short-term assays have shown that BPA is weakly estrogenic. In addition, the issue of species- and strain-differences in susceptibility to BPA was raised. The treatment of ovariectomized (OVX) Wistar rats with BPA at doses of 11-250 mg/kg per day, s.c., for 7 days, resulted in significant dose-dependent regrowth of uterus in uterotrophic assay. Additionally, the stimulation of anterior pituitary gland growth and induction of hyperprolactinaemia, as determined by wet organ weight and radioimmunoassay (RIA), respectively, were also dose-dependent (at 128 and 250 mg/kg per day, P < 0.05). Prolactin immunostaining of anterior pituitary glands revealed that BPA at a dose of 250 mg/kg per day increased the number of prolactin-immunopositive cells by 63% compared to OVX rats. These results demonstrate that the reproductive tract and neuroendocrine axis of Wistar rats are able to respond to BPA. Furthermore, the pituitary gland hypertrophy and hyperprolactinaemia can be mediated, at least partly, by increase in number of prolactin-immunoreactive cells. The long-term consequences of this proliferation are yet unknown but neoplasm formation is an obvious possibility.
Adolescents comprise approximately 20% of all gestational trophoblastic disease patients and have high adhesion to follow up. The disease did not affect their reproductive capacity, and chances of a normal subsequent gestation were high.
RESUMOEvidências acumuladas indicam que a saúde dos seres humanos, animais e espécies selvagens pode sofrer conseqüências adversas da exposição a produtos químicos presentes no meio ambiente e que interagem com o sistema endócrino, tais como bifenilas policloradas, dioxinas, estrogênios de ocorrência natural e sintéticos. Por outro lado, permanecem incertezas científicas com respeito aos dados relatados e, também, quanto à hipótese de haver níveis suficientemente elevados de exposição a estes agentes, a ponto de exercer efeito estrogênico generalizado sobre a população. Este trabalho revisa os principais tópi-cos relacionados a um dos xenoestrogênios que vem sendo mais recentemente estudado: o Bisfenol A (BFA), um monômero de plástico policarbonato, com pouca homologia estrutural com o estradiol (E 2 ) mas semelhante ao dietilestilbestrol (DES), hexestriol e componente bisfenóli-co do tamoxifeno. O presente trabalho comenta e analisa criticamente os efeitos do BFA sobre o trato reprodutivo e função lactotrófica em animais de experimentação, à luz das informações disponíveis e experiên-cia do grupo nesta área, e recomenda algumas necessidades de pesquisa. ABSTRACTSome evidences indicate that humans and domestic and wildlife species might suffer adverse consequences from exposure to environmental chemicals that interact with the endocrine system, including polychlorinated biphenyls, dioxins, synthetic and naturally occurring plant estrogens. However, considerable scientific uncertainty remains regarding the causes of these reported effects and whether sufficiently high levels of endocrine-disrupting chemicals exist in the ambient environment to exert adverse effects on the general population. This review summarizes the principal issues related to bisphenol A, an environmental endocrine disrupting chemical with estrogen activity. Bisphenol A is a monomer of plastics and has little structural homology with estradiol, sharing similarity with synthetic estrogens such as diethylstilbestrol and with the bisphenolic component of tamoxifen. In the light of available information and our laboratory experience in this field of research, this work comments and critically analyses the effects of BPA on the reproductive tract and lactotroph function in several rat strains, and also offers some recommendations for additional research.
Background. An evaluation of the performance of a Referral Center in the diagnosis, treatment and follow up of adolescents with gestational trophoblastic disease. Methods. In a 13-year prospective cohort study, between March 1987 and March 2000, 124 adolescents with gestational trophoblastic disease were followed up and/or treated by a multidisciplinary team. Adolescents underwent strict clinical and laboratory control after mole evacuation to guarantee adhesion to follow up, early diagnosis, and prompt treatment of persistent disease. The Student-Fischer t-test and the chi-square test were used for the statistic analysis of the results. Results. Adolescents represented 21.3% of the 583 patients with gestational trophoblastic disease: 102 (82.3%) had uncomplicated hydatidiform moles, and 22 (17.7%) underwent chemotherapy for persistent gestational trophoblastic disease or a gestational trophoblastic tumor. Complications were diagnosed earlier (p Ͻ 0.001) in patients managed and treated at the referral center. Of the adolescents with complications, 81.8% were low risk, 54.5% were at the International Federation of Gynecology and Obstetrics stage I, and 90.9% were treated with chemotherapy only. Time to remission and follow up were shorter for uncomplicated hydatidiform moles (9.8 ∫ 3.4 weeks and 8.8 ∫ 1.8 months, respectively) than for persistent disease (16.2 ∫ 5.8 weeks and 45 ∫ 24.5 months, respectively). Adhesion to follow up was similar in the two groups (84.2% and 91.8%). To this date, 50% of the adolescents have had one or more gestations, and 82% of these pregnancies were normal. Conclusions. Adolescents comprise approximately 20% of all gestational trophoblastic disease patients and have high adhesion to follow up. The disease did not affect their reproductive capacity, and chances of a normal subsequent gestation were high.
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