RESUMO
Patterns of diversification in Neotropical plants have been studied intensively over the past decades. Most studies have focused on groups that migrated to and radiated into the Neotropics, however, with little focus on understanding diversification patterns in indigenous Neotropical groups. This study focuses on Solanum section Brevantherum Seithe (Solanaceae), a group of Neotropical nightshade shrubs or treelets defined mostly by terminal inflorescences with long peduncles, plurifoliate sympodial units and porrect-stellate, dendritic-echinoid, or lepidote trichomes. We generated sequences from two nuclear (ITS, waxy) and one plastid marker (trnT-F) to infer phylogenetic relationships under Bayesian and Maximum likelihood approaches. We reconstructed a time-calibrated tree to estimate both the ages of main splits and the ancestral ranges of the lineages. Finally, we carried out a biogeographic stochastic mapping (BSM) analysis to determine the main processes driving current distributions of the group. Results show the non-monophyly of the section as previously recognized and the homoplasy of morphological characters traditionally used to circumscribe it. Two main clades that encompass most species formerly recognized in section Brevantherum are recovered and named as the Erianthum and Abutiloides clades. Divergence time estimates suggest that the Erianthum and Abutiloides clades split around 5.7 Mya in the upper Miocene. Two main dispersal events from the Atlantic rainforest are supported in the Erianthum clade: one dispersal to Mesoamerica and a second dispersal to the Northern Andes. Within the Abutiloides clade, cladogenetic events were restricted to the Andean region. Our BSM analysis suggests within-area speciation and range expansion as the main processes shaping the extant distribution of species of both clades. As no putative morphological synapomorphies can yet be assigned to what could correspond to a new circumscription of Solanum section Brevantherum (with the exclusion of Solanum bullatum Vell. and inclusion of S. inelegans Rusby and four species described since the group last revision) we discourage the continued use of what would be an ambiguous sectional nomenclature.
Assuntos
Filogenia , Filogeografia , Solanum/genética , Teorema de Bayes , Funções VerossimilhançaRESUMO
Resumen: la hormona antimülleriana, inicialmente denominada sustancia inhibitoria mülleriana, es una glicoproteína homodimérica de 12,5 kDa, que pertenece a la familia del factor de crecimiento transformante beta (TGF-ß) y desempeña un papel crucial en la diferenciación sexual masculina al favorecer la regresión de los conductos de Müller. Dado que su producción en el varón es principalmente por las células de Sertoli inmaduras, en las últimas décadas ha crecido su utilidad más allá de la evaluación de la función ovárica y tratamientos de fertilidad en las mujeres, lo que ha permitido evaluar en el varón la función testicular y los estados de hipogonadismo, trastornos de la diferenciación sexual, pubertad patológica, criptorquidia, entre otras condiciones clínicas revisadas en este manuscrito. Además, esta revisión describe el rol fisiológico de la hormona antimülleriana en los testículos prepuberales y las pruebas de laboratorio disponibles para su medición. (AU)
Abstract: The antimullerian hormone, initially referred as mullerian inhibitory substance, is a 12.5 kDa homodimeric glycoprotein, belonging to the transforming growth factor beta (TGF-ß) family that playing a crucial role in male sexual differentiation by favoring regression of the Mullerian ducts. Since their production in the male is mainly by the immature Sertoli cells, in the last decades its usefulness has growth beyond the evaluation of the ovarian function and female fertility treatments, which has allowed evaluating the testicular function in male and affections such as hypogonadism, disorders of sexual differentiation, pathological puberty, cryptorchidism and others clinical conditions reviewed in this manuscript. In addition, this review describes the physiological role of the antimüllerian hormone in the prepubertal testes and the laboratory tests available for its measurement. (AU)
Assuntos
Humanos , Vulnerabilidade SexualRESUMO
Resumen: la hormona antimülleriana es una glicoproteína homodimérica perteneciente a la superfamilia del factor de crecimiento transformantes beta (TGF-ß). Esta hormona desempeña un papel fundamental en la regresión de los conductos müllerianos en el embrión masculino. En los niños se produce en los testículos, por las células de Sertoli, hasta la pubertad y a partir de allí disminuye lentamente a valores residuales por el resto de la vida. En las mujeres la hormona antimülleriana es secretada por las células de la granulosa de pequeños folículos en el ovario, donde sus niveles reflejan con exactitud la reserva folicular ovárica. Por tal motivo, esta hormona es considerada un marcador extremadamente sensible del envejecimiento ovárico y una herramienta valiosa en el diagnóstico y el reconocimiento de la recurrencia de tumores de células de la granulosa. La evaluación de la hormona antimülleriana también es de importancia clínica en la predicción de la respuesta ovárica, el cese de la función ovárica y la reproducción asistida. Además, puede servir como marcador diagnóstico del síndrome de ovario poliquístico, en los casos en que el examen ultrasonográfico no sea posible de realizar. Finalmente, la medición de los niveles séricos de la hormona antimülleriana, durante la vida reproductiva de la mujer, representa una herramienta ideal para la evaluación de la reserva folicular ovárica. En esta revisión se presenta el rol fisiológico de la hormona antimülleriana en las mujeres, al igual que las principales utilidades clínicas de su medición y las pruebas de laboratorio disponibles para este fin. (AU)
Abstract: Anti-mullerian hormone is a homodimeric glycoprotein belonging to the transforming growth factor beta (TGF-ß) super family. Anti-mullerian hormone plays a fundamental role in the regression of mullerian ducts in male embryo. In boys, it is produced by Sertoli cells of the testes until puberty where slowly decreases to residual values for the rest of the life. In female, it is secreted by granulosa cells of small follicles in the ovary where their levels accurately reflect the ovarian follicular reserve. Therefore, anti-mullerian hormone has been considered as extremely sensitive marker of ovarian aging and a valuable tool in the diagnosis and the recognition of recurrence of granulosa cell tumor. Anti-mullerian hormone evaluation is also of clinical importance in predicting of ovarian responsiveness, ovarian function cessation, and in assisted reproduction. In addition, anti-mullerian hormone could be a diagnostic marker of polycystic ovary syndrome in cases in which ultrasonographic examination is not possible. Finally, the measurement of serum anti-mullerian hormone levels during woman's reproductive life represents an ideal tool for the assessment of the ovarian follicular reserve. This review presents the physiological role of anti-mullerian hormone in women, as well as the main clinical benefits of its measurement and the laboratory tests available for this purpose. (AU)