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Hope, S.

Publications and source records attributed to Hope, S..

3 recordsLinked to original sources

Expression of cell-adhesion molecules in E. coli: a high-throughput method to identify paracellular modulators

Cell-adhesion molecules (CAM) are membrane proteins responsible for cell-cell interactions or cell-extracellular matrix interactions. Among these proteins, claudins (CLDN), occludin (OCLN), and junctional adhesion molecules (JAM) are components of the tight junction (TJ), the single proteic structure tasked with safeguarding the paracellular space. The TJ is responsible for controlled permeability of blood-tissue barriers, regulating the passage of molecule passage by size and charge. Currently there is no translational solution to manipulate the TJ with the exception of Focused Ultra-sound (FUS) and Micro bubbling (MB) techniques, still in clinical trials. Here we describe the expression of TJ proteins in the outer membrane of E. coli and report its consequences. When expression is induced, the unicellular behavior of E. coli is replaced with multicellular aggregations that can be quantified using Flow Cytometry (FC). The adhesion properties of the aggregates are representative of the individual membrane proteins expressed. This method, called iCLASP (inspection of cell-adhesion molecules aggregation through FC protocols), allows the high-throughput interrogation of small-molecules influence on paracellular permeability, enabling for the first time the discovery of its modulators for therapeutic strategies.

synthetic biology↗

Sex differences in the relationship between social difficulties and executive dysfunction in children and adolescents with autism spectrum disorder

The prevalence of autism spectrum disorder (ASD) in boys is nearly four times higher than in girls, and the causes of this sex difference are not fully known. Difficulties in executive function may be involved in development of autistic symptomatology. Here we investigated sex differences in the relationship between executive function in everyday life and social dysfunction symptoms in a sample of 116 children (25 girls) aged 5-19 years with IQ above 70 and with a diagnosis of ASD. They were assessed with the Behavior Rating Inventory of Executive Function (BRIEF) and the Autism Diagnostic Interview Revised (ADI-R). We found no significant differences in BRIEF or ADI-R scores between girls and boys after correcting for multiple testing. Nested linear regression models revealed significant sex differences in the relationship between executive function and both reciprocal social interaction (p<0.001) and communication (p=0.001) over and above the main effects of age, sex, IQ and comorbid attention deficit/hyperactivity disorder diagnosis. We did not find sex differences in the relationship between executive dysfunction and restricted and repetitive behaviors. Altogether, our results provide a greater understanding of the sex-specific characteristics of ASD and may suggest that boys and girls can benefit from different intervention strategies.

neuroscience↗

Common risk variants identified in autism spectrum disorder

Autism spectrum disorder (ASD) is a highly heritable and heterogeneous group of neurodevelopmental phenotypes diagnosed in more than 1% of children. Common genetic variants contribute substantially to ASD susceptibility, but to date no individual variants have been robustly associated with ASD. With a marked sample size increase from a unique Danish population resource, we report a genome-wide association meta-analysis of 18,381 ASD cases and 27,969 controls that identifies five genome-wide significant loci. Leveraging GWAS results from three phenotypes with significantly overlapping genetic architectures (schizophrenia, major depression, and educational attainment), seven additional loci shared with other traits are identified at equally strict significance levels. Dissecting the polygenic architecture we find both quantitative and qualitative polygenic heterogeneity across ASD subtypes, in contrast to what is typically seen in other complex disorders. These results highlight biological insights, particularly relating to neuronal function and corticogenesis and establish that GWAS performed at scale will be much more productive in the near term in ASD, just as it has been in a broad range of important psychiatric and diverse medical phenotypes.

genetics↗