Psychosis risk candidate ZNF804A localizes to synapses and regulates neurite formation and dendritic spine structure

BackgroundVariation in the gene encoding zinc finger binding protein 804A (ZNF804A) is associated with schizophrenia (SCZ) and bipolar disorder (BP). Evidence suggests that ZNF804A is a regulator of gene transcription and is present in nuclear and extranuclear compartments. However, a detailed examination of ZNF804A distribution and its neuronal functions has yet to be performed.MethodsThe localization of ZNF804A protein was examined in neurons derived from human neural progenitor cells (hNPCs), human induced pluripotent stem cells (hiPSCs) or in primary rat cortical neurons. Additionally, siRNA-mediated knockdown of ZNF804A was conducted to determine its role in neurite formation, maintenance of dendritic spine morphology and responses to activity-dependent stimulations.ResultsEndogenous ZNF804A protein localized to somato-dendritic compartments and co-localized with the putative synaptic markers in young neurons derived from hNPCs and hiPSCs. In mature rat neurons, Zfp804A, the homolog of ZNF804A, was present in a subset of dendritic spines and co-localized with synaptic proteins in specific nanodomains, as determined by superresolution microscopy. Interestingly, knockdown of ZNF804A attenuated neurite outgrowth in young neurons, an effect potentially mediated by reduced neuroligin-4 (NLGN4) expression. Furthermore, knockdown of ZNF804A in mature neurons resulted in the loss of dendritic spine density, and impaired responses to activity-dependent stimulation.ConclusionsThese data reveal a novel subcellular distribution for ZNF804A within somato-dendritic compartments and a nanoscopic organisation at excitatory synapses. Moreover, our results suggest that ZNF804A plays an active role in neurite formation, maintenance of dendritic spines and activity-dependent structural plasticity

Impact of animal strain on gene expression in a rat model of acute cardiac rejection

<p>Abstract</p> <p>Background</p> <p>The expression levels of many genes show wide natural variation among strains or populations. This study investigated the potential for animal strain-related genotypic differences to confound gene expression profiles in acute cellular rejection (ACR). Using a rat heart transplant model and 2 different rat strains (Dark Agouti, and Brown Norway), microarrays were performed on native hearts, transplanted hearts, and peripheral blood mononuclear cells (PBMC).</p> <p>Results</p> <p>In heart tissue, strain alone affected the expression of only 33 probesets while rejection affected the expression of 1368 probesets (FDR 10% and FC ≥ 3). Only 13 genes were affected by both strain and rejection, which was < 1% (13/1368) of all probesets differentially expressed in ACR. However, for PBMC, strain alone affected 265 probesets (FDR 10% and FC ≥ 3) and the addition of ACR had little further effect. Pathway analysis of these differentially expressed strain effect genes connected them with immune response, cell motility and cell death, functional themes that overlap with those related to ACR. After accounting for animal strain, additional analysis identified 30 PBMC candidate genes potentially associated with ACR.</p> <p>Conclusion</p> <p>In ACR, genetic background has a large impact on the transcriptome of immune cells, but not heart tissue. Gene expression studies of ACR should avoid study designs that require cross strain comparisons between leukocytes.</p

Ciliary proteins Bbs8 and Ift20 promote planar cell polarity in the cochlea

Primary cilia have been implicated in the generation of planar cell polarity (PCP). However, variations in the severity of polarity defects in different cilia mutants, coupled with recent demonstrations of non-cilia-related actions of some cilia genes, make it difficult to determine the basis of these polarity defects. To address this issue, we evaluated PCP defects in cochlea from a selection of mice with mutations in cilia-related genes. Results indicated notable PCP defects, including mis-oriented hair cell stereociliary bundles, in Bbs8 and Ift20 single mutants that are more severe than in other cilia gene knockouts. In addition, deletion of either Bbs8 or Ift20 results in disruptions in asymmetric accumulation of the core PCP molecule Vangl2 in cochlear cells, suggesting a role for Bbs8 and/or Ift20, possibly upstream of core PCP asymmetry. Consistent with this, co-immunoprecipitation experiments indicate direct interactions of Bbs8 and Ift20 with Vangl2. We observed localization of Bbs and Ift proteins to filamentous actin as well as microtubules. This could implicate these molecules in selective trafficking of membrane proteins upstream of cytoskeletal reorganization, and identifies new roles for cilia-related proteins in cochlear PCP

Sacral nerve stimulation allows for decreased antegrade continence enema use in children with severe constipation.

BackgroundSacral nerve stimulation (SNS) can be beneficial for children with constipation, but no studies have focused on children with constipation severe enough to require antegrade continence enemas (ACEs). Our objective was to evaluate the efficacy of SNS in children with constipation treated with ACE.MethodsUsing a prospective patient registry, we identified patients &lt;21years old who were receiving ACE prior to SNS placement. We compared ACE/laxative usage, PedsQL Gastrointestinal Symptom Scale (GSS), Fecal Incontinence Quality of Life Scale (FIQL), Fecal Incontinence Severity Index (FISI), and Vancouver Dysfunctional Elimination Syndrome Score (DES) at baseline and progressive follow-up time intervals.ResultsTwenty-two patients (55% male, median 12years) were included. Median ACE frequency decreased from 7 per week at baseline to 1 per week at 12months (p&lt;0.0001). Ten children (45%) had their cecostomy/appendicostomy closed. Laxative use, GSS, FIQL, and DES did not change. FISI improved over the first 12months with statistical significance reached only at 6months (p=0.02). Six (27%) children experienced complications after SNS that required further surgery.ConclusionsIn children with severe constipation dependent on ACE, SNS led to a steady decrease in ACE usage with nearly half of patients receiving cecostomy/appendicostomy closure within 2years.Level of evidenceIV

Whole genome sequencing for the diagnosis of neurological repeat expansion disorders in the UK: a retrospective diagnostic accuracy and prospective clinical validation study

BACKGROUND: Repeat expansion disorders affect about 1 in 3000 individuals and are clinically heterogeneous diseases caused by expansions of short tandem DNA repeats. Genetic testing is often locus-specific, resulting in underdiagnosis of people who have atypical clinical presentations, especially in paediatric patients without a previous positive family history. Whole genome sequencing is increasingly used as a first-line test for other rare genetic disorders, and we aimed to assess its performance in the diagnosis of patients with neurological repeat expansion disorders. METHODS: We retrospectively assessed the diagnostic accuracy of whole genome sequencing to detect the most common repeat expansion loci associated with neurological outcomes (AR, ATN1, ATXN1, ATXN2, ATXN3, ATXN7, C9orf72, CACNA1A, DMPK, FMR1, FXN, HTT, and TBP) using samples obtained within the National Health Service in England from patients who were suspected of having neurological disorders; previous PCR test results were used as the reference standard. The clinical accuracy of whole genome sequencing to detect repeat expansions was prospectively examined in previously genetically tested and undiagnosed patients recruited in 2013-17 to the 100 000 Genomes Project in the UK, who were suspected of having a genetic neurological disorder (familial or early-onset forms of ataxia, neuropathy, spastic paraplegia, dementia, motor neuron disease, parkinsonian movement disorders, intellectual disability, or neuromuscular disorders). If a repeat expansion call was made using whole genome sequencing, PCR was used to confirm the result. FINDINGS: The diagnostic accuracy of whole genome sequencing to detect repeat expansions was evaluated against 793 PCR tests previously performed within the NHS from 404 patients. Whole genome sequencing correctly classified 215 of 221 expanded alleles and 1316 of 1321 non-expanded alleles, showing 97·3% sensitivity (95% CI 94·2-99·0) and 99·6% specificity (99·1-99·9) across the 13 disease-associated loci when compared with PCR test results. In samples from 11 631 patients in the 100 000 Genomes Project, whole genome sequencing identified 81 repeat expansions, which were also tested by PCR: 68 were confirmed as repeat expansions in the full pathogenic range, 11 were non-pathogenic intermediate expansions or premutations, and two were non-expanded repeats (16% false discovery rate). INTERPRETATION: In our study, whole genome sequencing for the detection of repeat expansions showed high sensitivity and specificity, and it led to identification of neurological repeat expansion disorders in previously undiagnosed patients. These findings support implementation of whole genome sequencing in clinical laboratories for diagnosis of patients who have a neurological presentation consistent with a repeat expansion disorder. FUNDING: Medical Research Council, Department of Health and Social Care, National Health Service England, National Institute for Health Research, and Illumina

Infants with esophageal atresia and right aortic arch: Characteristics and outcomes from the Midwest Pediatric Surgery Consortium

Purpose Right sided aortic arch (RAA) is a rare anatomic finding in infants with esophageal atresia with or without tracheoesophageal fistula (EA/TEF). In the presence of RAA, significant controversy exists regarding optimal side for thoracotomy in repair of the EA/TEF. The purpose of this study was to characterize the incidence, demographics, surgical approach, and outcomes of patients with RAA and EA/TEF. Methods A multi-institutional, IRB approved, retrospective cohort study of infants with EA/TEF treated at 11 children's hospitals in the United States over a 5-year period (2009 to 2014) was performed. All patients had a minimum of one-year follow-up. Results In a cohort of 396 infants with esophageal atresia, 20 (5%) had RAA, with 18 having EA with a distal TEF and 2 with pure EA. Compared to infants with left sided arch (LAA), RAA infants had a lower median birth weight, (1.96 kg (IQR 1.54–2.65) vs. 2.57 kg (2.00–3.03), p = 0.01), earlier gestational age (34.5 weeks (IQR 32–37) vs. 37 weeks (35–39), p = 0.01), and a higher incidence of congenital heart disease (90% vs. 32%, p  0.29). Conclusion RAA in infants with EA/TEF is rare with an incidence of 5%. Compared to infants with EA/TEF and LAA, infants with EA/TEF and RAA are more severely ill with lower birth weight and higher rates of prematurity and complex congenital heart disease. In neonates with RAA, surgical repair of the EA/TEF is technically feasible via thoracotomy from either chest. A higher incidence of anastomotic strictures may occur with a right-sided approach

Understanding the Value of Tumor Markers in Pediatric Ovarian Neoplasms

Purpose The purpose of this study was to determine the diagnostic accuracy of tumor markers for malignancy in girls with ovarian neoplasms. Methods A retrospective review of girls 2–21 years who presented for surgical management of an ovarian neoplasm across 10 children's hospitals between 2010 and 2016 was performed. Patients who had at least one concerning feature on imaging and had tumor marker testing were included in the study. Sensitivity, specificity, and negative and positive predictive values (PPV) of tumor markers were calculated. Results Our cohort included 401 patients; 22.4% had a malignancy. Testing for tumor markers was inconsistent. AFP had high specificity (98%) and low sensitivity (42%) with a PPV of 86%. The sensitivity, specificity, and PPV of beta-hCG was 44%, 76%, and 32%, respectively. LDH had high sensitivity (95%) and Inhibin A and Inhibin B had high specificity (97% and 92%, respectively). Conclusions Tumor marker testing is helpful in preoperative risk stratification of ovarian neoplasms for malignancy. Given the variety of potential tumor types, no single marker provides enough reliability, and therefore a panel of tumor marker testing is recommended if there is concern for malignancy. Prospective studies may help further elucidate the predictive value of tumor markers in a pediatric ovarian neoplasm population