Modulating Glutathione Thiol Status Alters Pancreatic β-cell Morphogenesis in the Developing Zebrafish (Danio rerio) Embryo

Emerging evidence suggests that redox-active chemicals perturb pancreatic islet development. To better understand potential mechanisms for this, we used zebrafish (Danio rerio) embryos to investigate roles of glutathione (GSH; predominant cellular redox buffer) and the transcription factor Nrf2a (Nfe2l2a; zebrafish Nrf2 coortholog) in islet morphogenesis. We delineated critical windows of susceptibility to redox disruption of beta-cell morphogenesis, interrogating embryos at 24, 48 and 72 h post fertilization (hpf) and visualized Nrf2a expression in the pancreas using whole-mount immunohistochemistry at 96 hpf. Chemical GSH modulation at 48 hpf induced significant islet morphology changes at 96 hpf. Pro-oxidant exposures to tert-butylhydroperoxide (77.6 mu M; 10-min at 48 hpf) or tert-butylhydroquinone (1 mu M; 48-56 hpf) decreased beta-cell cluster area at 96 hpf. Conversely, exposures to antioxidant N-acetylcysteine (bolsters GSH pools; 100 mu M; 48-72 hpf) or sulforaphane (activates Nrf2a; 20 mu M; 48-72 hpf) significantly increased islet areas. Nrf2a was also stabilized in beta-cells: 10-min exposures to 77.6 mu M tert-butylhydroperoxide significantly increased Nrf2a protein compared to control islet cells that largely lack stabilized Nrf2a; 10-min exposures to higher (776 mu M) tert-butylhydroperoxide concentration stabilized Nrf2a throughout the pancreas. Using biotinylated-GSH to visualize in situ protein glutathionylation, islet cells displayed high protein glutathionylation, indicating oxidized GSH pools. The 10-min high (776 mu M) tert-butylhydroperoxide exposure (induced Nrf2a globally) decreased global protein glutathionylation at 96 hpf. Mutant fish expressing inactive Nrf2a were protected against tert-butylhydroperoxide-induced abnormal islet morphology. Our data indicate that disrupted redox homeostasis and Nrf2a stabilization during pancreatic beta-cell development impact morphogenesis, with implications for disease states at later life stages. Our work identifies a potential molecular target (Nrf2) that mediates abnormal beta-cell morphology in response to redox disruptions. Moreover, our findings imply that developmental exposure to exogenous stressors at distinct windows of susceptibility could diminish the reserve redox capacity of beta-cells, rendering them vulnerable to later-life stresses and disease

Developmental exposures to perfluorooctanesulfonic acid (PFOS) impact embryonic nutrition, pancreatic morphology, and adiposity in the zebrafish, \u3cem\u3eDanio rerio\u3c/em\u3e

Perfluorooctanesulfonic acid (PFOS) is a persistent environmental contaminant previously found in consumer surfactants and industrial fire-fighting foams. PFOS has been widely implicated in metabolic dysfunction across the lifespan, including diabetes and obesity. However, the contributions of the embryonic environment to metabolic disease remain uncharacterized. This study seeks to identify perturbations in embryonic metabolism, pancreas development, and adiposity due to developmental and subchronic PFOS exposures and their persistence into later larval and juvenile periods. Zebrafish embryos were exposed to 16 or 32 μM PFOS developmentally (1–5 days post fertilization; dpf) or subchronically (1–15 dpf). Embryonic fatty acid and macronutrient concentrations and expression of peroxisome proliferator-activated receptor (PPAR) isoforms were quantified in embryos. Pancreatic islet morphometry was assessed at 15 and 30 dpf, and adiposity and fish behavior were assessed at 15 dpf. Concentrations of lauric (C12:0) and myristic (C14:0) saturated fatty acids were increased by PFOS at 4 dpf, and PPAR gene expression was reduced. Incidence of aberrant islet morphologies, principal islet areas, and adiposity were increased in 15 dpf larvae and 30 dpf juvenile fish. Together, these data suggest that the embryonic period is a susceptible window of metabolic programming in response to PFOS exposures, and that these early exposures alone can have persisting effects later in the lifecourse

Transforming training into practice with the conflict management framework: a mixed methods study

Objective To implement and evaluate the use of the conflict management framework (CMF) in four tertiary UK paediatric services. Design Mixed methods multisite evaluation including prospective pre and post intervention collection of conflict data alongside semistructured interviews. Setting Eight inpatient or day care wards across four tertiary UK paediatric services. Interventions The two-stage CMF was used in daily huddles to prompt the recognition and management of conflict. Results Conflicts were recorded for a total of 67 weeks before and 141 weeks after implementation of the CMF across the four sites. 1000 episodes of conflict involving 324 patients/families across the four sites were recorded. After implementation of the CMF, time spent managing episodes of conflict around the care of a patient was decreased by 24% (p < 0.001) (from 73 min to 55 min) and the estimated cost of this staff time decreased by 20% (p < 0.02) (from £26 to £21 sterling per episode of conflict). This reduction occurred despite conflict episodes after implementation of the CMF having similar severity to those before implementation. Semistructured interviews highlighted the importance of broad multidisciplinary leadership and training to embed a culture of proactive and collaborative conflict management. Conclusions The CMF offers an effective adjunct to conflict management training, reducing time spent managing conflict and the associated staff costs

Genomic analyses in Cornelia de Lange Syndrome and related diagnoses: Novel candidate genes, <scp>genotype–phenotype</scp> correlations and common mechanisms

Cornelia de Lange Syndrome (CdLS) is a rare, dominantly inherited multisystem developmental disorder characterized by highly variable manifestations of growth and developmental delays, upper limb involvement, hypertrichosis, cardiac, gastrointestinal, craniofacial, and other systemic features. Pathogenic variants in genes encoding cohesin complex structural subunits and regulatory proteins (NIPBL, SMC1A, SMC3, HDAC8, and RAD21) are the major pathogenic contributors to CdLS. Heterozygous or hemizygous variants in the genes encoding these five proteins have been found to be contributory to CdLS, with variants in NIPBL accounting for the majority (&gt;60%) of cases, and the only gene identified to date that results in the severe or classic form of CdLS when mutated. Pathogenic variants in cohesin genes other than NIPBL tend to result in a less severe phenotype. Causative variants in additional genes, such as ANKRD11, EP300, AFF4, TAF1, and BRD4, can cause a CdLS‐like phenotype. The common role that these genes, and others, play as critical regulators of developmental transcriptional control has led to the conditions they cause being referred to as disorders of transcriptional regulation (or “DTRs”). Here, we report the results of a comprehensive molecular analysis in a cohort of 716 probands with typical and atypical CdLS in order to delineate the genetic contribution of causative variants in cohesin complex genes as well as novel candidate genes, genotype–phenotype correlations, and the utility of genome sequencing in understanding the mutational landscape in this population

Clinical Sequencing Exploratory Research Consortium: Accelerating Evidence-Based Practice of Genomic Medicine

Despite rapid technical progress and demonstrable effectiveness for some types of diagnosis and therapy, much remains to be learned about clinical genome and exome sequencing (CGES) and its role within the practice of medicine. The Clinical Sequencing Exploratory Research (CSER) consortium includes 18 extramural research projects, one National Human Genome Research Institute (NHGRI) intramural project, and a coordinating center funded by the NHGRI and National Cancer Institute. The consortium is exploring analytic and clinical validity and utility, as well as the ethical, legal, and social implications of sequencing via multidisciplinary approaches; it has thus far recruited 5,577 participants across a spectrum of symptomatic and healthy children and adults by utilizing both germline and cancer sequencing. The CSER consortium is analyzing data and creating publically available procedures and tools related to participant preferences and consent, variant classification, disclosure and management of primary and secondary findings, health outcomes, and integration with electronic health records. Future research directions will refine measures of clinical utility of CGES in both germline and somatic testing, evaluate the use of CGES for screening in healthy individuals, explore the penetrance of pathogenic variants through extensive phenotyping, reduce discordances in public databases of genes and variants, examine social and ethnic disparities in the provision of genomics services, explore regulatory issues, and estimate the value and downstream costs of sequencing. The CSER consortium has established a shared community of research sites by using diverse approaches to pursue the evidence-based development of best practices in genomic medicine

Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201

“A Wound That Was Already Festering”: The Burdens of a Racial Justice Program on Teachers of Color

Background:: Research that documents the influence of anti-racism programs on teacher practice shows some desired outcomes, including developing critical consciousness to support students of color and educate others about stereotyping; understanding how racial bias affects one’s teaching and relationships with students; and implementing anti-racist approaches in schoolwide policies and practice. At the same time, research on anti-racist professional development (PD) also highlights the challenges of engaging in this work when white teachers, in particular, respond defensively or dismissively. Studies have shown how these responses can reinforce stereotyping behavior among white participants and reinscribe unequal social relationships. Research Questions:: This article aims to answer the following questions: (1) How do white educators, if they do at all, display resistance to racial justice work? (2) How does resistance among white educators, if it does so at all, shape the experiences of educators of color? (3) How can schools reduce the potential burden of racial justice work on educators of color? Research Design:: This article draws on data from a case study of a New York City elementary school that participated in a yearlong racial justice program. Data sources include semi-structured interviews with school and program leaders; focus groups with members of the racial equity committee and other teachers; observations of professional development sessions, racial equity committee meetings, and other program activities; and artifacts related to the implementation of the program to deepen our understanding of the program’s implementation and responses from multiple stakeholders. Recommendations:: Grounded in critical race theory (CRT), the findings from this study paint a complex picture of the behaviors that white teachers may employ that derail racial justice work, the emotional and professional burden of that resistance on educators of color, and promising approaches for confronting resistance in order to advance racial equity. Beyond identifying the potential costs of engaging in racial justice work, our findings also offer schools and educators promising approaches for challenging white resistance while not perpetuating racial harm. We propose an implementation model that intentionally shields educators of color from the remonstrations of white resistors and the additional toll they can take on their time and well-being. Moreover, given what we know about the outsized role school leaders play in shaping school environments and professional cultures, it is essential that school leaders show commitment to organizational transformation, while developing the skills required to confront varying degrees of white resistance

The relationship between diabetes mellitus and exfoliation syndrome in a United States Veterans Affairs population: a case-control study

Earlier studies suggest that an inverse relationship exists between diabetes mellitus and exfoliation syndrome (ES). We evaluated the relationship between diabetes mellitus and ES while controlling for important covariates. In addition, we investigated whether glucose control, as measured by glycosylated hemoglobin (HbA1c) levels, differed between the subset of diabetic patients with and without ES. This retrospective case-control study included outpatients seen in Veterans Affairs Boston Healthcare System eye clinics. Exfoliation cases (n=328) and controls (n=328) were drawn from the same clinic and matched for age. For all participants, we ascertained diabetes status, sex, race, body mass index, and glaucoma status. Among patients with diabetes mellitus, we collected the 5 most recent HbA1c levels and type of diabetes control. Diabetes mellitus was present in 96 (29.2%) cases and in 114 (34.8%) controls. In multivariate analysis, no statistically significant relationship between diabetes mellitus and ES (OR=0.77; 95% CI, 0.55-1.07) was identified. When glaucoma status was added as a covariate, the results were essentially unchanged (OR=0.81, 95% CI, 0.57-1.14). Adjusted mean HbA1c levels were similar in diabetic patients with (6.85%; 95% CI, 6.66-7.04) and without (7.05%; 95% CI, 6.87-7.22) ES (P=0.14). In this predominately white male population, we did not observe a statistically significant relationship between diabetes mellitus and ES. In addition, HbA1c levels did not vary among diabetic patient based on exfoliation status