16 research outputs found

    Espécies crípticas em Pagamea coriacea sensu lato (Rubiaceae): evidências morfológicas, ecológicas e de comportamento reprodutivo em um contexto simpátrico

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    In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an overlap in flowering phases between the two groups, but the pattern of floral maturation differed. Ecologically, plants of group B were found in more shaded habitats and over sandstone bedrocks, while group A was prevalent in deeper sandy soils as canopy plants. The significances of morphological and environmental differences were tested by a multivariate analysis of variance, and a canonical discriminant analysis assessed the importance of variables. The coexistence in sympatry of two discrete morphological groups in the P. coriacea s.l., with different habitat preferences and reproductive behaviors, indicates they represent distinct species.O objetivo deste estudo foi testar se o complexo de espécies Pagamea coriacea inclui múltiplas espécies, usando evidências morfológicas, ecológicas e de comportamento reprodutivo. Um total de 147 árvores foram amostradas e monitoradas em três locais próximos na Amazônia Central, Brasil. Análises multivariadas de dados morfológicos indicaram dois grupos discretos (A e B), que coincidem com diferenças no tipo de casca, cada um por sua vez com subgrupos que representam dimorfismo sexual. Contudo, um indivíduo distintamente hermafrodita foi encontrado no grupo B. Todas as plantas pistiladas produziram frutos, mas também foram observados frutos para 23% das plantas estaminadas do grupo B, e para 5% das estaminadas do grupo A. Essa variação sugere que ambos grupos possuem um sistema sexual entre dioicia e ginodioicia. Houve sobreposição das fases de floração e frutificação entre os dois grupos, mas o padrão de maturação de flores foi diferente. Quanto ao hábitat, o grupo B predominou em situações de sombra e em solos arenosos rasos sobre lajes de pedra, enquanto o grupo A ocorreu em solos arenosos mais profundos e no dossel da vegetação. A coexistência de dois grupos morfológicos discretos no complexo P. coriacea s.l., com diferenças ecológicas e de comportamento reprodutivo, indica que correspondem a duas espécies distintas

    Follow-up of children born after ICSI with epididymal spermatozoa

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    Item does not contain fulltextBACKGROUND: To evaluate the safety of ICSI with epididymal sperm, this study compared children born after ICSI treatment with epididymal sperm and children conceived after IVF and ICSI with ejaculated sperm. Additionally, the results of a multidisciplinary, multicentre follow-up of the children conceived with epididymal sperm at 2 years of age are described. METHODS: This follow-up study included 378 children conceived after ICSI with epididymal sperm (percutaneous epididymal sperm aspiration: PESA group) and a control group of 1192 IVF and 1126 ICSI (with ejaculated sperm) children, all with a gestational age of 20 weeks or more. Questionnaires were sent at birth, 1 year and 4 years of age, collecting data on parental, pregnancy and child factors. A total of 148 PESA children were assessed at 2 years of age for motor performance, mental- and language development and compared with the Dutch norms. RESULTS: PESA children showed no increased risks for stillbirths, total deaths and malformations. They also did not differ from IVF and ICSI children in gender rate, birthweight and gestational age. The mental Bayley score was higher (P < 0.05) for PESA singletons and parents reported fewer (P < 0.05) behavioural problems in the PESA group than the Dutch reference group. The scores for syntactic and lexical development for the PESA singletons were better (P < 0.05) than the Dutch standards. CONCLUSIONS: ICSI with epididymal sperm does not lead to more stillbirths or congenital malformations in comparison to IVF and ICSI with ejaculated sperm and does not lead to poor development in comparison with the Dutch reference group
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