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Human but not mouse islets transplanted into immunodeficient NSG mice effectively accumulate lipid droplets (LDs). Because chronic lipid exposure is associated with islet β-cell dysfunction, we investigated LD accumulation in the intact human and mouse pancreas over a range of ages and states of diabetes. Very few LDs were found in normal human juvenile pancreatic acinar and islet cells, with numbers subsequently increasing throughout adulthood. While accumulation appeared evenly distributed in postjuvenile acinar and islet cells in donors without diabetes, LDs were enriched in islet α- and β-cells from donors with type 2 diabetes (T2D). LDs were also found in the islet β-like cells produced from human embryonic cell-derived β-cell clusters. In contrast, LD accumulation was nearly undetectable in the adult rodent pancreas, even in hyperglycemic and hyperlipidemic models or 1.5-year-old mice. Taken together, there appear to be significant differences in pancreas islet cell lipid handling between species, and the human juvenile and adult cell populations. Moreover, our results suggest that LD enrichment could be impactful to T2D islet cell function.
© 2019 by the American Diabetes Association.
In this comprehensive systematic review and meta-analysis of group design studies of nonpharmacological early interventions designed for young children with autism spectrum disorder (ASD), we report summary effects across 7 early intervention types (behavioral, developmental, naturalistic developmental behavioral intervention [NDBI], TEACCH, sensory-based, animal-assisted, and technology-based), and 15 outcome categories indexing core and related ASD symptoms. A total of 1,615 effect sizes were gathered from 130 independent participant samples. A total of 6,240 participants, who ranged in age from 0-8 years, are represented across the studies. We synthesized effects within intervention and outcome type using a robust variance estimation approach to account for the nesting of effect sizes within studies. We also tracked study quality indicators, and report an additional set of summary effect sizes that restrict included studies to those meeting prespecified quality indicators. Finally, we conducted moderator analyses to evaluate whether summary effects across intervention types were larger for proximal as compared with distal effects, and for context-bound as compared to generalized effects. We found that when study quality indicators were not taken into account, significant positive effects were found for behavioral, developmental, and NDBI intervention types. When effect size estimation was limited to studies with randomized controlled trial (RCT) designs, evidence of positive summary effects existed only for developmental and NDBI intervention types. This was also the case when outcomes measured by parent report were excluded. Finally, when effect estimation was limited to RCT designs and to outcomes for which there was no risk of detection bias, no intervention types showed significant effects on any outcome. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
To identify valid measures of vocal development in young children with autism spectrum disorder in the early stages of language learning, we evaluated the convergent validity, divergent validity, and sensitivity to change (across 12 months) of two measures of vocal communication and two measures of vocal complexity through conventional coding of communication samples. Participants included 87 children with autism spectrum disorder (M = 23.42 months at entry). All four vocal variables demonstrated consistent evidence of convergent validity, divergent validity, and sensitivity to change with large effect sizes for convergent validity and sensitivity to change. The results highlight the value of measuring vocal communication and vocal complexity in future studies.
BACKGROUND - CaM (calmodulin) mutations are associated with congenital arrhythmia susceptibility (calmodulinopathy) and are most often de novo. In this report, we sought to broaden the genotype-phenotype spectrum of calmodulinopathies with 2 novel calmodulin mutations and to investigate mosaicism in 2 affected families.
METHODS - CaM mutations were identified in 4 independent cases by DNA sequencing. Biochemical and electrophysiological studies were performed to determine functional consequences of each mutation.
RESULTS - Genetic studies identified 2 novel CaM variants (-E141K in 2 cases; -E141V) and one previously reported CaM pathogenic variant (-D130G) among 4 probands with shared clinical features of prolonged QTc interval (range 505-725 ms) and documented ventricular arrhythmia. A fatal outcome occurred for 2 of the cases. The parents of all probands were asymptomatic with normal QTc duration. However, 2 of the families had multiple affected offspring or multiple occurrences of intrauterine fetal demise. The mother from the family with recurrent intrauterine fetal demise exhibited the -E141K mutant allele in 25% of next-generation sequencing reads indicating somatic mosaicism, whereas -D130G was present in 6% of captured molecules of the paternal DNA sample, also indicating mosaicism. Two novel mutations (E141K and E141V) impaired Ca binding affinity to the C-domain of CaM. Human-induced pluripotent stem cell-derived cardiomyocytes overexpressing mutant or wild-type CaM showed that both mutants impaired Ca-dependent inactivation of L-type Ca channels and prolonged action potential duration.
CONCLUSIONS - We report 2 families with somatic mosaicism associated with arrhythmogenic calmodulinopathy, and demonstrate dysregulation of L-type Ca channels by 2 novel CaM mutations affecting the same residue. Parental mosaicism should be suspected in families with unexplained fetal arrhythmia or fetal demise combined with a documented CaM mutation.
OBJECTIVE - We describe the risk factors for peri-procedural and spontaneous arterial ischemic stroke (AIS) in children with cardiac disease.
METHODS - We identified children with cardiac causes of AIS enrolled in the International Pediatric Stroke Study registry from January 2003 to July 2014. Isolated patent foramen ovale was excluded. Peri-procedural AIS (those occurring during or within 72 hours of cardiac surgery, cardiac catheterization, or mechanical circulatory support) and spontaneous AIS that occurred outside of these time periods were compared.
RESULTS - We identified 672 patients with congenital or acquired cardiac disease as the primary risk factor for AIS. Among these, 177 patients (26%) had peri-procedural AIS and 495 patients (74%) had spontaneous AIS. Among non-neonates, spontaneous AIS occurred at older ages (median 4.2 years, interquartile range 0.97 to 12.4) compared with peri-procedural AIS (median 2.4 years, interquartile range 0.35 to 6.1, P < 0.001). About a third of patients in both groups had a systemic illness at the time of AIS. Patients who had spontaneous AIS were more likely to have a preceding thrombotic event (16 % versus 9 %, P = 0.02) and to have a moderate or severe neurological deficit at discharge (67% versus 33%, P = 0.01) compared to those with peri-procedural AIS.
CONCLUSIONS - Children with cardiac disease are at risk for AIS at the time of cardiac procedures but also outside of the immediate 72 hours after procedures. Many have acute systemic illness or thrombotic event preceding AIS, suggesting that inflammatory or prothrombotic conditions could act as a stroke trigger in this susceptible population.
Copyright © 2019 Elsevier Inc. All rights reserved.
Germline mutations in SAMD9 and SAMD9L genes cause MIRAGE (myelodysplasia, infection, restriction of growth, adrenal hypoplasia, genital phenotypes, and enteropathy) (OMIM: *610456) and ataxia-pancytopenia (OMIM: *611170) syndromes, respectively, and are associated with chromosome 7 deletions, myelodysplastic syndrome (MDS), and bone marrow failure. In this retrospective series, we report outcomes of allogeneic hematopoietic cell transplantation (HCT) in patients with hematologic disorders associated with SAMD9/SAMD9L mutations. Twelve patients underwent allogeneic HCT for MDS (n = 10), congenital amegakaryocytic thrombocytopenia (n = 1), and dyskeratosis congenita (n = 1). Exome sequencing revealed heterozygous mutations in SAMD9 (n = 6) or SAMD9L (n = 6) genes. Four SAMD9 patients had features of MIRAGE syndrome. Median age at HCT was 2.8 years (range, 1.2 to 12.8 years). Conditioning was myeloablative in 9 cases and reduced intensity in 3 cases. Syndrome-related comorbidities (diarrhea, infections, adrenal insufficiency, malnutrition, and electrolyte imbalance) were present in MIRAGE syndrome cases. One patient with a familial SAMD9L mutation, MDS, and morbid obesity failed to engraft and died of refractory acute myeloid leukemia. The other 11 patients achieved neutrophil engraftment. Acute post-transplant course was complicated by syndrome-related comorbidities in MIRAGE cases. A patient with SAMD9L-associated MDS died of diffuse alveolar hemorrhage. The other 10 patients had resolution of hematologic disorder and sustained peripheral blood donor chimerism. Ten of 12 patients were alive with a median follow-up of 3.1 years (range, 0.1 to 14.7 years). More data are needed to refine transplant approaches in SAMD9/SAMD9L patients with significant comorbidities and to develop guidelines for their long-term follow-up.
Copyright © 2019 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.
BACKGROUND AND PURPOSE - The purpose of the study is to characterize diffusion tensor imaging indices in the developing spinal cord, evaluating differences based on age and cord region. Describing the progression of DTI indices in the pediatric cord increases our understanding of spinal cord development.
MATERIALS AND METHODS - A retrospective analysis was performed on DTI acquired in 121 pediatric patients (mean, 8.6 years; range, 0.3-18.0 years) at Monroe Carell Jr. Children's Hospital at Vanderbilt from 2017 to 2018. Diffusion-weighted images (15 directions; = 750 s/mm; slice thickness, 5 mm; in-plane resolution, 1.0 × 1.0 mm) were acquired on a 3T scanner in the cervicothoracic and/or thoracolumbar cord. Manual whole-cord segmentation was performed. Images were masked and further segmented into cervical, upper thoracic, thoracolumbar, and conus regions. Analyses of covariance were performed for each DTI-derived index to investigate how age affects diffusion across cord regions, and 95% confidence intervals were calculated across age for each derived index and region. Post hoc testing was performed to analyze regional differences.
RESULTS - Analyses of covariance revealed significant correlations of age with axial diffusivity, mean diffusivity, and fractional anisotropy (all, < .001). There were also significant differences among cord regions for axial diffusivity, radial diffusivity, mean diffusivity, and fractional anisotropy (all, < .001).
CONCLUSIONS - This research demonstrates that diffusion evolves in the pediatric spinal cord during development, dependent on both cord region and the diffusion index of interest. Future research could investigate how diffusion may be affected by common pediatric spinal pathologies.
© 2019 by American Journal of Neuroradiology.
Purpose The impact of home use of a remote microphone system (RMS) on the caregiver production of, and child access to, child-directed speech (CDS) in families with a young child with hearing loss was investigated. Method We drew upon extant data that were collected via Language ENvironment Analysis (LENA) recorders used with 9 families during 2 consecutive weekends (RMS weekend and no-RMS weekend). Audio recordings of primary caregivers and their children with hearing loss obtained while wearing and not wearing an RMS were manually coded to estimate the amount of CDS produced. The proportion of CDS that was likely accessible to children with hearing loss under both conditions was determined. Results Caregivers produced the same amount of CDS when using and when not using the RMS. However, it was concluded that children with hearing loss, on average, could potentially access 12% more CDS if caregivers used an RMS because of their distance from their children when talking to them. Conclusion Given our understanding of typical child language development, findings from this investigation suggest that children with hearing loss could receive auditory, speech, and language benefits from the use of an RMS in the home environment.
Purpose The purpose of this study was to evaluate if higher quantity, diversity, and grammatical informativeness of verb phrases in parent follow-in utterances (i.e., utterances that mapped onto child attentional leads) were significantly related to later expressive verb vocabulary in children with autism spectrum disorder (ASD). Method We examined these associations in a sample of 31 toddlers with ASD and their parents in a longitudinal correlational study. Key aspects of parents' verb input were measured in 2 video-recorded 15-min parent-child free-play sessions. Child expressive verb vocabulary was measured using parent report. Results An aggregate variable composed of the quantity, diversity, and grammatical informativeness of parent verb input in follow-in utterances across the 2 parent-child sessions strongly and positively predicted later child expressive verb vocabulary, total R = .25, even when early child expressive verb vocabulary was controlled, R change = .17. Parent follow-in utterances without verbs were not significantly related to later child expressive verb vocabulary, R = .001. Conclusions These correlational findings are initial steps toward developing a knowledge base for how strong verb vocabulary skills might be facilitated in children with ASD.
The relation between caregiver follow-in utterances with verbs presented in different states of dyadic engagement and later child expressive verb vocabulary in children with autism spectrum disorder (ASD) was examined in 29 toddlers with ASD and their caregivers. Caregiver verb input in follow-in utterances presented during higher order supported joint engagement (HSJE) accounted for a significant, large amount of variance in later child verb vocabulary; R= .26. This relation remained significant when controlling for early verb vocabulary or verb input in lower support engagement states. Other types of talk in follow-in utterances in HSJE did not correlate with later verb vocabulary. These findings are an important step towards identifying interactional contexts that facilitate verb learning in children with ASD.