Using C. elegans to decipher the cellular and molecular mechanisms underlying neurodevelopmental disorders

Prova tipográfica (uncorrected proof)Neurodevelopmental disorders such as epilepsy, intellectual disability (ID), and autism spectrum disorders (ASDs) occur in over 2 % of the population, as the result of genetic mutations, environmental factors, or combination of both. In the last years, use of large-scale genomic techniques allowed important advances in the identification of genes/loci associated with these disorders. Nevertheless, following association of novel genes with a given disease, interpretation of findings is often difficult due to lack of information on gene function and effect of a given mutation in the corresponding protein. This brings the need to validate genetic associations from a functional perspective in model systems in a relatively fast but effective manner. In this context, the small nematode, Caenorhabditis elegans, presents a good compromise between the simplicity of cell models and the complexity of rodent nervous systems. In this article, we review the features that make C. elegans a good model for the study of neurodevelopmental diseases. We discuss its nervous system architecture and function as well as the molecular basis of behaviors that seem important in the context of different neurodevelopmental disorders. We review methodologies used to assess memory, learning, and social behavior as well as susceptibility to seizures in this organism. We will also discuss technological progresses applied in C. elegans neurobiology research, such as use of microfluidics and optogenetic tools. Finally, we will present some interesting examples of the functional analysis of genes associated with human neurodevelopmental disorders and how we can move from genes to therapies using this simple model organism.The authors would like to acknowledge Fundação para a Ciência e Tecnologia (FCT) (PTDC/SAU-GMG/112577/2009). AJR and CB are recipients of FCT fellowships: SFRH/BPD/33611/2009 and SFRH/BPD/74452/2010, respectively

Antibiotic prophylaxis for the prevention of recurrent urinary tract infection in children with low grade vesicoureteral reflux: results from a prospective randomized study.

International audiencePURPOSE: Antibiotic prophylaxis is given to children at risk for urinary tract infection. However, evidence concerning its effectiveness in grade I to III vesicoureteral reflux is lacking. The objective of this study was to determine whether antibiotic prophylaxis reduces the incidence of urinary tract infection in young children with low grade vesicoureteral reflux. MATERIALS AND METHODS: Children 1 month to 3 years old with grade I to III vesicoureteral reflux were assigned randomly to receive daily cotrimoxazole or no treatment, and followed for 18 months. A urinary tract infection constituted an exit criterion. Infection-free survival rates were calculated using the Kaplan-Meier method and compared using the log rank test. RESULTS: A total of 225 children were enrolled in the study. Distribution of gender, age at inclusion and reflux grade were similar between the 2 groups. There was no significant difference in the occurrence of urinary tract infection between the 2 groups (17% vs 26%, p = 0.2). However, a significant association was found between treatment and patient gender (p = 0.017). Prophylaxis significantly reduced urinary tract infection in boys (p = 0.013), most notably in boys with grade III vesicoureteral reflux (p = 0.042). CONCLUSIONS: These data suggest that antibiotic prophylaxis does not reduce the overall incidence of urinary tract infection in children with low grade vesicoureteral reflux. However, such a strategy may prevent further urinary tract infection in boys with grade III reflux

Diagnosis of cardiac disease in pediatric end-stage renal disease

Background. Cardiac disease is a significant cause of morbidity and mortality in children with end-stage renal disease (ESRD). This study aimed to report the frequency of cardiac disease diagnostic methods used in US pediatric maintenance hemodialysis patients

Development and validation of a predictive model for death in acquired severe ADAMTS13 deficiency-associated idiopathic thrombotic thrombocytopenic purpura: the French TMA Reference Center experience.

International audienceBackground. Acquired thrombotic thrombocytopenic purpura is still associated with a 10-20% death rate. So far, early prognostic factors of death could not be clearly identified. To identify prognostic factors associated with 1-month death in thrombotic thrombocytopenic purpura patients with acquired severe (=10N. A 3-level risk score for early death was defined and confirmed in the validation cohort using these variables, with higher values corresponding to increased risk of early death.Conclusions. A risk score for early death was defined in patients with thrombotic thrombocytopenic purpura and validated on an independent cohort. This score should help to stratify early treatment and intensify patients with a worse prognosis