Sex differences in microstructural alterations in the corpus callosum tracts in drug-naïve children with ADHD.

Widespread alterations in the corpus callosum (CC) microstructure and organization have been found in children with attention-deficit/hyperactivity disorder (ADHD); however, few studies have investigated the diffusion characteristics and volume of transcallosal fiber tracts defined by specific cortical projections in ADHD, which is important for identifying distinct functional interhemispheric connection abnormalities. In the current study, an automated fiber-tract quantification (AFQ) approach based on diffusion tensor imaging identified seven CC tracts according to their cortical projections and estimated diffusion parameters and volume among 76 drug-naïve ADHD patients (53 boys and 23 girls) and 37 typically developing children (TDC) (20 boys and 17 girls) matched for age, IQ, and handedness. We found significantly lower fractional anisotropy (FA) in the occipital and superior parietal tracts and higher mean diffusivity (MD) in the posterior, superior parietal and anterior frontal tracts in children with ADHD compared with TDC.

Abnormal functional network centrality in drug-naïve boys with attention-deficit/hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed neurodevelopmental disorder in childhood and is characterized by inattention, impulsivity, and hyperactivity. Observations of distributed functional abnormalities in ADHD suggest aberrant large-scale brain network connectivity. However, few studies have measured the voxel-wise network centrality of boys with ADHD, which captures the functional relationships of a given voxel within the entire connectivity matrix of the brain.

Aberrant white matter properties of the callosal tracts implicated in girls with attention-deficit/hyperactivity disorder.

Aberrant microstructure of the callosal tracts has been found in boys with attention-deficit/hyperactivity disorder (ADHD). However, it is unclear whether the previously identified white matter (WM) alterations in boys with ADHD are also present in girls with ADHD. Thus, we applied diffusion tensor imaging (DTI) to investigate WM alterations in the callosal tracts in girls with ADHD.

Functional Connectivity of Attention-Related Networks in Drug-Naïve Children With ADHD.

This study aimed to explore alterations of seed-based functional connectivity (FC) in dorsal attention network (DAN), ventral attention network (VAN), and default mode network (DMN) in ADHD children. A voxel-based comparison of FC maps between 46 drug-naïve children with ADHD and 31 healthy controls (HCs) and correlation analysis between connectivity features and behavior were performed. Compared with the HCs, children with ADHD were characterized by hyperconnectivity between DAN and regions of DMN and by hyperconnectivity between DMN and a set of regions involved in somatosensory, visual, and auditory cortices.

Facile preparation of calcium phosphate nanoparticles for siRNA delivery: effect of synthesis conditions on physicochemical and biological properties.

Over the past few years, efforts in developing efficient non-viral carriers for the intracellular delivery of siRNA have become increasingly intensive, due to the great potentials exhibited by siRNA-mediated gene silencing. Major challenges existing in the research field of non-viral siRNA delivery are to develop safe and cost effective delivery systems. Calcium phosphate (CaP) is known to be biocompatible and non-cytotoxic.