Immunoglobulin A Vasculitis With Intussusception in Children.

BACKGROUND: Immunoglobulin A (IgA) vasculitis with intussusception is acute and severe vasculitis combined with acute abdomen in children. The diagnosis of the disease depends on the results of imaging examinations, and its treatment mainly includes enema and surgery. The literature summarized the detailed diagnosis and treatment data in previous literature reports. METHODS: We described the clinical manifestations, ultrasonic features, and treatment of patients admitted to a single center and reviewed previous literature regarding cases with detailed clinical data in the PubMed database within the past 20 years. RESULTS: The review included 36 patients, including 22 boys and 14 girls. A total of 32 patients were diagnosed using ultrasound (88.9%). The main sites of intussusception were the ileum and ileocolon in 16 (44.4%) and 11 (30.6%) cases, respectively. Thirteen patients (36.1%) were treated with enema, with 6 responding to the treatment. 26 patients (72.2%) underwent surgical treatment. Patients with ileal intussusception were more likely to be treated with surgery than those with colonic intussusception (P < .05). The single-center clinical data of 23 patients showed that there was no significant difference in laboratory test findings between patients with and without surgical treatment (P > .05). Patients with long insertion lengths were more likely to require surgery and resection (P < .05). CONCLUSIONS: Ultrasonography is the first-line investigation for diagnosis. The main sites of intussusception were ileum and ileocolon. The length of intubation was related to surgery; treatment is according to the intussusception site. Air enema is not suitable for intussusception of the small intestine.

Aberrant outputs of cerebellar nuclei and targeted rescue of social deficits in an autism mouse model.

The cerebellum is heavily connected with other brain regions, sub-serving not only motor but also non-motor functions. Genetic mutations leading to cerebellar dysfunction are associated with mental diseases, but cerebellar outputs have not been systematically studied in this context. Here, we present three dimensional distributions of 50,168 target neurons of cerebellar nuclei (CN) from wild-type mice and Nlgn3R451C mutant mice, a mouse model for autism. Our results derived from 36 target nuclei show that the projections from CN to thalamus, midbrain and brainstem are differentially affected by Nlgn3R451C mutation. Importantly, Nlgn3R451C mutation altered the innervation power of CN→zona incerta (ZI) pathway, and chemogenetic inhibition of a neuronal subpopulation in the ZI that receives inputs from the CN rescues social defects in Nlgn3R451C mice. Our study highlights potential role of cerebellar outputs in the pathogenesis of autism and provides potential new therapeutic strategy for this disease.

Purkinje-cell-specific MeCP2 deficiency leads to motor deficits and autistic-like behavior due to aberrations in PTP1B-TrkB-SK signaling.

Patients with Rett syndrome suffer from a loss-of-function mutation of the Mecp2 gene, which results in various symptoms including autistic traits and motor deficits. Deletion of Mecp2 in the brain mimics part of these symptoms, but the specific function of methyl-CpG-binding protein 2 (MeCP2) in the cerebellum remains to be elucidated. Here, we demonstrate that Mecp2 deletion in Purkinje cells (PCs) reduces their intrinsic excitability through a signaling pathway comprising the small-conductance calcium-activated potassium channel PTP1B and TrkB, the receptor of brain-derived neurotrophic factor. Aberration of this cascade, in turn, leads to autistic-like behaviors as well as reduced vestibulocerebellar motor learning. Interestingly, increasing activity of TrkB in PCs is sufficient to rescue PC dysfunction and abnormal motor and non-motor behaviors caused by Mecp2 deficiency. Our findings highlight how PC dysfunction may contribute to Rett syndrome, providing insight into the underlying mechanism and paving the way for rational therapeutic designs.