Excess of serotonin affects neocortical pyramidal neuron migration

The serotonin transporter (SERT) is a key molecule involved in the homeostasis of extracellular levels of serotonin and is regulated developmentally. Genetic deletion of SERT in rodents increases extracellular levels of serotonin and affects cellular processes involved in neocortical circuit assembly such as barrel cortex wiring and cortical interneuron migration. Importantly, pharmacological blockade of SERT during brain development leads to phenotypes relevant to psychiatry in rodents and to an increased risk for autism spectrum disorders in humans. Furthermore, developmental adversity interacts with genetically-driven variations of serotonin function in humans and nonhuman primates to increase the risk for a variety of stress-related phenotypes. In this study, we investigate whether an excess of serotonin affects the migration of neocortical pyramidal neurons during development. Using in utero electroporation combined with time-lapse imaging to specifically monitor pyramidal neurons during late mouse embryogenesis, we show that an excess of serotonin reversibly affects the radial migration of pyramidal neurons. We further identify that the serotonin receptor 5-HT6 is expressed in pyramidal neuron progenitors and that 5-HT6 receptor activation replicates the effects of serotonin stimulation. Finally, we show that the positioning of superficial layer pyramidal neurons is altered in vivo in SERT knockout mice. Taken together, these results indicate that a developmental excess of serotonin decreases the migration speed of cortical pyramidal neurons, affecting a fundamental step in the assembly of neural circuits. These findings support the hypothesis that developmental dysregulation of serotonin homeostasis has detrimental effects on neocortical circuit formation and contributes to increased vulnerability to psychiatric disorders

The program for biodiversity research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes

Mortalidade materna por eclâmpsia Eclampsia as a cause of maternal mortality

OBJETIVO: analisar fatores associados à mortalidade materna causada por eclâmpsia. MÉTODOS: estudo de coorte retrospectivo revisando-se prontuários médicos dos partos assistidos no Conjunto Hospitalar de Sorocaba (janeiro/1995 a dezembro/2005). Variáveis pesquisadas: ano do parto, características sócio-demográficas maternas, antecedentes familiares, pessoais e obstétricos, características da gestação, parto, puerpério, atendimento realizado, evolução e condições de alta. A análise estatística incluiu teste exato de Fisher, correlação de Pearson, e regressão múltipla de Poisson. RESULTADOS: registraram-se 35.973 partos, 179 casos de eclâmpsia, 52 com sérias complicações, 23 com maior permanência no tratamento intensivo e 8 evoluíram para óbito. A proporção de eclâmpsia decresceu no período (0,90% para 0,37%; r= - 0,746; p=0,008), mas mantendo a proporção de casos com sérias complicações (0,25% para 0,17%, r= - 0,45; p=0,162). A proporção de óbitos foi maior entre pacientes não brancas (RR=9,10; IC95%=1,83-45,23; p=0,007) e menor entre as tratadas com sulfato de magnésio (RR=0,08; IC95%=0,02-0,35; p= 0,001). CONCLUSÕES: reduziu-se a proporção de eclâmpsia entre os partos assistidos no Conjunto Hospitalar de Sorocaba, porém, a eclâmpsia continua sendo importante causa de óbito materno na região. Este estudo revela que é fundamental o aperfeiçoamento das medidas de diagnóstico precoce e tratamento da pré-eclâmpsia e eclâmpsia pela rede de atenção à saúde.<br>OBJECTIVE: to assess the factors associated with maternal mortality resulting from eclampsia. METHODS: a retrospective cohort study reviewing the medical records of deliveries carried out at the Sorocaba Hospital Compound (between January 1995 and December 2005). The variables included were: year of delivery, social and demographic characteristics of mother, personal, family and obstetric history, characteristics of the pregnancy, delivery and puer-perium, the kind care given, the evolution of the case, and the conditions for release from hospital. The statistical analysis involved the use of Fisher 's exact test, the Pearson correlation and Poisson 's multiple regression. RESULTS: 35 973 deliveries were registered, 179 of which involved cases of eclampsia, 52 of them with serious complications, twenty-three resulting in a longer stay in intensive care and eight in death. The incidence of eclampsia decreased over the period (from 0.90% to 0.37%; r= -0.746;p= 0.008), although the proportion of cases with serious complications remained unchanged (0.25% compared with 0.17%, r= - 0.45; p=0.162). The proportion of patients who died was larger among non-white patients (RR=9.10; CI95%= 1.83-45.23; p= 0.007) and lower among those treated with magnesium sulfate (RR=0.08; CI95%= 0.02-0.35; p= 0.001). CONCLUSIONS: the incidence of eclampsia among deliveries performed at the Sorocaba Hospital Compound decreased, although the disease still represents a significant cause of maternal death in the region. This study shows that it is essential that early diagnostic measures and treatment of preeclampsia and eclampsia be perfected by the health care system

Freqüência e critérios para indicar a episiotomia Frecuencia y criterios para indicar la episiotomía Frequency and criteria for the indication of episiotomy

Trata-se de estudo exploratório com o objetivo de identificar a freqüência, os tipos e os critérios adotados para indicar a episiotomia. Foram entrevistados 12 médicos e 12 enfermeiras que prestam assistência à parturiente no Hospital Universitário da Universidade de São Paulo. A episiotomia ocorreu em 76,2% dos partos normais; as indicações mais freqüentes foram: rigidez perineal (28,7%), primiparidade (23,7%), feto macrossômico (11,9%), prematuridade (10,2%). O tipo mais citado foi médio-lateral direito (92,0%), justificado por: aprendizado durante a formação acadêmica (25,9%), ser adotada rotineiramente (19,4%), menor chance de lesar o esfíncter anal (16,1%), menor risco de complicações (16,1%). É necessário rever as práticas de atendimento à parturiente, considerando as evidências científicas e condutas individualizadas.<br>Trata-se de estudo exploratório com o objetivo de identificar a freqüência, os tipos e os critérios adotados para indicar a episiotomia. Foram entrevistados 12 médicos e 12 enfermeiras que prestam assistência à parturiente no Hospital Universitário da Universidade de São Paulo. A episiotomia ocorreu em 76,2% dos partos normais; as indicações mais freqüentes foram: rigidez perineal (28,7%), primiparidade (23,7%), feto macrossômico (11,9%), prematuridade (10,2%). O tipo mais citado foi médio-lateral direito (92,0%), justificado por: aprendizado durante a formação acadêmica (25,9%), ser adotada rotineiramente (19,4%), menor chance de lesar o esfíncter anal (16,1%), menor risco de complicações (16,1%). É necessário rever as práticas de atendimento à parturiente, considerando as evidências científicas e condutas individualizadas.<br>This is an exploratory study aimed at identifying the frequency, the types and the criteria adopted to recommend episiotomy. Twelve doctors and 12 nurses who attend women giving birth at the University of São Paulo's Hospital Universitário were interviewed. Episiotomy was performed in 76.2 percent of the normal births; the most frequent indications were: perineal rigidity (28.7 percent), primiparity (23.7 percent), macrossomic infant (11.9 percent) and prematurity (10.2 percent). The most mentioned type was the right medium-lateral (92.0 percent), and the justifications were: it was learned during academic formation (25.9 percent); it is adopted routinely (19.4 percent); with it there is a lesser chance for causing lesions to the anal sphincter (16.1 percent); with it there is a lesser risk of complications (16.1 percent). The practices for attending women giving birth must be revised taking into account scientific evidences and individualized conducts