ABSTRACT
Background: Genome-wide association studies (GWASs) have identified numerous genetic variants associated with attention-deficit/hyperactivity disorder (ADHD), which is considered highly genetically heritable. However, because most of the variants located in the non-coding region of the human genome, the onset of ADHD requires further exploration. Methods: The risk genes involved in ADHD were identified by integrating GWAS summary data and expression quantitative trait locus (eQTL) data using summary-data-based Mendelian randomization (SMR) method. We then used a stratified linkage disequilibrium score regression (LDSR) method to estimate the contribution of ADHD-relevant tissues to its heritability to screen out disease-relevant tissues. To determine the ADHD-relevant cell types, we used an R package for expression-weighted cell type enrichment (EWCE) analysis. Results: By integrating the brain eQTL data and ADHD GWAS data using SMR, we identified 247 genes associated with ADHD. The LDSR applied to specifically expressed genes results showed that the ADHD risk genes were mainly enriched in brain tissue, especially in the mesencephalon, visual cortex, and frontal lobe regions. Further cell-type-specific analysis suggested that ADHD risk genes were highly expressed in excitatory neurons. Conclusion: The study showed that the etiology of ADHD is associated with excitatory neurons in the midbrain, visual cortex, and frontal lobe regions.
ABSTRACT
OBJECTIVE: To investigate the efficacy of gastroscopic treatment in the treatment of membranous duodenal stenosis. METHODS: We performed a retrospective study of 6 patients with membranous duodenal stenosis, aging from 7days to 37months, who underwent gastroscopic balloon dilatation in a children's hospital between January 2012 and December 2013. All surgical procedures of balloon dilatation were performed under direct gastroscopic vision. The balloon dilators with diameter 8mm and 10mm for neonates and children aged over one month, respectively, were placed through the foramen of the membranous stenosis. The septum in the membranous stenosis was gradually extended by increasing diameter of the balloon dilator. The residual septum was removed by gastroscopic electrocauterization. RESULTS: The membranous stenosis in duodenum of all children was successfully expanded by gastroscopic balloon dilatation, and only one case with residual septum received gastroscopic electrocauterization. No complications such as bleeding, intestinal perforation, etc., were observed. Postoperative radiography using iodine-based contrast media showed that the gastrointestinal tract was unobstructed. During a follow-up period ranging from 3 to 24months, all patients ate normally without vomiting and abdominal distension and grew normally. CONCLUSION: Gastroscopic balloon dilatation is an effective method in the treatment of membranous duodenal stenosis in children. For the patients with residual septum, they can be cured by using gastroscopic electrocauterization.
