Distinct arbuscular mycorrhizal fungal communities associate with different manioc landraces and Amazonian soils.

Manioc (Manihot esculenta Crantz) is an important tropical crop that depends on arbuscular mycorrhizal (AM) association for its nutrition. However, little is known about the richness and species composition of AM fungal communities associating with manioc and possible differences across soils and manioc landraces. We studied the diversity and composition of AM fungal communities present in the roots of different manioc landraces and surrounding soils in indigenous shifting cultivation fields on different Amazonian soil types. A total of 126 AM fungal virtual taxa (VT; phylogenetically defined taxonomic units) were recovered from soil and root samples using 454 sequencing of AM fungal SSU rRNA gene amplicons. Different AM fungal communities occurred in different soil types. Minor differences occurred in the composition of AM fungal community associating with different manioc landraces, but AM fungal richness was not different among them. There was a low similarity between the AM fungal communities colonizing manioc roots and those recorded in the soil, independently of differences in soil properties or the manioc landrace evaluated. Rhizophagus manihotis and Glomus VT126 were the most abundant AM fungal species colonizing manioc roots. Contrasting with the results of earlier spore-based investigations, all the AM fungi identified as indicator species of particular manioc landraces were morphologically unknown Glomus species. In conclusion, different manioc landraces growing in common conditions associated with distinct AM fungal communities, whereby AM fungal communities in soils did not necessarily reflect the AM fungal communities colonizing manioc roots.

Impact of alien pines on local arbuscular mycorrhizal fungal communities-evidence from two continents.

The introduction of alien plants can influence biodiversity and ecosystems. However, its consequences for soil microbial communities remain poorly understood. We addressed the impact of alien ectomycorrhizal (EcM) pines on local arbuscular mycorrhizal (AM) fungal communities in two regions with contrasting biogeographic histories: in South Africa, where no native EcM plant species are present; and in Argentina, where EcM trees occur naturally. The effect of alien pines on AM fungal communities differed between these regions. In South Africa, plantations of alien EcM pines exhibited lower AM fungal richness and significantly altered community composition, compared with native fynbos. In Argentina, the richness and composition of local AM fungal communities were similar in plantations of alien EcM pines and native forest. However, the presence of alien pines resulted in slight changes to the phylogenetic structure of root AM fungal communities in both regions. In pine clearcut areas in South Africa, the richness and composition of AM fungal communities were intermediate between the native fynbos and the alien pine plantation, which is consistent with natural regeneration of former AM fungal communities following pine removal. We conclude that the response of local AM fungal communities to alien EcM pines differs between biogeographic regions with different histories of species coexistence.

The composition of arbuscular mycorrhizal fungal communities in the roots of a ruderal forb is not related to the forest fragmentation process.

Land-use changes and forest fragmentation have strong impact on biodiversity. However, little is known about the influence of new landscape configurations on arbuscular mycorrhizal fungal (AMF) community composition. We used 454 pyrosequencing to assess AMF diversity in plant roots from a fragmented forest. We detected 59 virtual taxa (VT; phylogenetically defined operational taxonomic units) of AMF - including 10 new VT - in the roots of Euphorbia acerensis. AMF communities were mainly composed of members of family Glomeraceae and were similar throughout the fragmented landscape, despite variation in forest fragment size (i.e. small, medium and large) and isolation (i.e. varying pairwise distances). AMF communities in forest fragments were phylogenetically clustered compared with the global, but not regional and local AMF taxon pools. This indicates that non-random community assembly processes possibly related to dispersal limitation at a large scale, rather than habitat filtering or biotic interactions, may be important in structuring the AMF communities. In this system, forest fragmentation did not appear to influence AMF community composition in the roots of the ruderal plant. Whether this is true for AMF communities in soil and the roots of other ecological groups of host plants or in other habitats deserves further study.

Transplante renal e gravidez / Renal transplantation and pregnancy

Pacientes com insuficiência renal crônica são frequentemente inférteis e a taxa (tasa) de gravidez gira em torno de 1:200. Perda da libido, disfunção ovariana, amenorréia e elevados níveis de prolactina contribuem para a infertilidade. Após (luego) o transplante, entretanto,a fertilidade pode retornar rapidamente e a as taxas de gravidez passam (alcanzan) para 1:50. Não há dúvidas de que essas mulheres constituem um grupo de alto risco e de elevadas taxas de problemas tanto maternos quanto perinatais. Desde a primeira gravidez de sucesso em uma portadora de transplante renal relatada em 1963, diversas publicações têm focado maiores incidências de síndromes hipertensivas, anemia, perda da função renal, pré-eclâmpsia, prematuridade, ruptura prematura de membranas, restrição de crescimento fetal e óbito perinatal. Nosso grupo, na Universidade Federal de SãoPaulo - Brasil tem acumulado experiência nesses casos en este trabalho relatamos nossa experiência comparando com os dados obtidos na literatura. Nós enfatizamos que somente o acompanhamento multiprofissional levará aos melhores resultados. Por fim, gostaríamos de manifestar o nosso desejo (deseo) de entrar em contato com outros grupos para discussão desses (de estos) casos e então aprendermos juntos.

Patients with chronic renal insufficiency are frequentlyinfertile and the incidence of pregnancy is 1:200. Loss oflibido, ovarian dysfunction, anovulatory vaginal bleeding, amenorrhea and high prolactin levels, all contribute to thisinfertility. However, after renal transplantation fertility canreturn rapidly with the chances of pregnancy increasingto about 1:50. There is no doubt that these women are aspecial high risk group with the potential for both maternaland perinatal problems. Since the first successfulpregnancy was reported in 1963 many other publication shave emphasized the increased incidence of hypertension,anaemia, renal function deterioration, pre-eclampsia,preterm delivery, preterm rupture of membranes, fetal growth restriction and stillbirths. At the Federal University of Sao Paulo - Brazil, we have emphasized that a multidisciplinary team approach is essential for their careand in this article we document and analyze the lessonslearnt from our significant single centre experience. We would be happy in contacting other groups of specialists interested in this special group of patients to exchangepoints of view and learn together.