The deubiquitinating enzyme USP7 regulates the transcription factor Nrf1 by modulating its stability in response to toxic metal exposure.

The nuclear factor E2-related factor 1 (Nrf1) transcription factor performs a critical role in regulating cellular homeostasis as part of the cellular stress response and drives the expression of antioxidants and detoxification enzymes among many other functions. Ubiquitination plays an important role in controlling the abundance and thus nuclear accumulation of Nrf1 proteins, but the regulatory enzymes that act on Nrf1 are not fully defined. Here, we identified ubiquitin specific protease 7 (USP7), a deubiquitinating enzyme, as a novel regulator of Nrf1 activity. We found that USP7 interacts with Nrf1a and TCF11-the two long protein isoforms of Nrf1. Expression of wildtype USP7, but not its catalytically defective mutant, resulted in decreased ubiquitination of TCF11 and Nrf1a, leading to their increased stability and increased transactivation of reporter gene expression by TCF11 and Nrf1a. In contrast, knockdown or pharmacologic inhibition of USP7 dramatically increased ubiquitination of TCF11 and Nrf1a and reduction of their steady state levels. Loss of USP7 function attenuated the induction of Nrf1 protein expression in response to treatment with arsenic and other toxic metals, and inhibition of USP7 activity significantly sensitized cells to arsenic treatment. Collectively, these findings suggest that USP7 may act to modulate abundance of Nrf1 protein to induce gene expression in response to toxic metal exposure.

Integrating health, education and culture in predicting Pacific children's English receptive vocabulary at 6 years: A classification tree approach.

AIM: Pacific children fare poorly on health and educational outcomes, including literacy. Early interventions are considered critical in reducing educational disparities. A prediction model was constructed to analyse the factors associated with Pacific children's English receptive vocabulary, an important component of English language development. METHODS: A birth cohort study of Pacific children was used to construct a classification tree model and predict the proportions of Pacific children who performed strongly in a standardised test of English receptive vocabulary at 6 years of age (n = 1019). Classification trees were constructed using 10-fold cross-validation (CV) and pruned using the one-standard-error rule. Prediction errors were directly estimated using leave-one-out CV. RESULTS: Analyses of misclassification errors from the pruned model gave false negative and positive rates of 19 and 19% from re-substitution and 54 and 21% from leave-one-out CV estimation, respectively. Of the predictors, maternal acculturation, small birthweight and performance in early developmental screening test at 4 years of age were found to have the highest goodness of split. CONCLUSIONS: The cultural environment to which Pacific children were exposed in early childhood, indicated by the maternal acculturation, was more crucial in distinguishing children with strong English-receptive vocabulary skills than socio-economic or prenatal conditions. This highlights the importance of integrating the cultural environment into designing measures for facilitating Pacific children's language development.

Emotional and Behavioral Trajectories of 2 to 9 Years Old Children Born to Opioid-Dependent Mothers.

Maternal opioid use in pregnancy has increased dramatically. Knowledge about children's longer-term emotional and behavioral development after prenatal opioid exposure is scarce. A regional sample of 89 opioid-exposed and 104 non-exposed comparison children were studied prospectively at ages 2, 4.5, and 9 years using the Strengths and Difficulties Questionnaire (SDQ) completed by primary caregivers. Across all childhood assessments, opioid-exposed children obtained significantly higher total difficulties scores than non-exposed comparison children. Growth curve modeling revealed that, relative to their same age peers, opioid-exposed children's emotional and behavioral difficulties significantly worsened over time. Moreover, fixed effects estimates showed that total difficulties trajectories were poorer for children subject to higher prenatal risk (Est = 1.78, 95% CI = [0.46, 3.09]) who were born to mothers with high levels of social adversity (1.11 [0.51, 1.71]), and were then raised in families characterized by high levels of psychosocial risk (1.94 [0.90, 2.98]) and unstable caregiving (1.91 [0.33, 3.48]). A complex set of pre- and postnatal processes contribute to opioid-exposed children's emotional and behavioral development. Efforts to mitigate the long-term consequences of opioid use in pregnancy need to consider both children's and their caregivers' biopsychosocial risks.

Patterns of early primary school-based literacy interventions among Pacific children from a nationwide health screening programme of 4 year olds.

Literacy success is critical to unlocking a child's potential and enhancing their future wellbeing. Thus, the early identification and redressing of literacy needs is vital. Pacific children have, on average, the lowest literacy achievement levels in New Zealand. However, this population is very diverse. This study sought to determine whether the current national health screening programme of pre-school children could be used as an early detection tool of Pacific children with the greatest literacy needs. Time-to-event analyses of literacy intervention data for Pacific children born in years 2005-2011 were employed. A multivariable Cox proportional hazard model was fitted, and predictive assessment made using training and test datasets. Overall, 59,760 Pacific children were included, with 6,861 (11.5%) receiving at least one literacy intervention. Tongan (hazard ratio [HR]: 1.33; 95% confidence interval [CI]: 1.23, 1.45) and Cook Island Maori (HR: 1.33; 95% CI: 1.21, 1.47) children were more likely to receive an intervention than Samoan children; whereas those children with both Pacific and non-Pacific ethnic identifications were less likely. However, the multivariable model lacked reasonable predictive power (Harrell's c-statistic: 0.592; 95% CI: 0.583, 0.602). Regardless, important Pacific sub-populations emerged who would benefit from targeted literacy intervention or policy implementation.

Construction of a biocompatible decellularized porcine hepatic lobe for liver bioengineering.

OBJECTIVE: One of the major obstacles in applying decellularized organs for clinical use is the recellularization step, during which huge numbers of cells are required to develop whole livers. We established a simple protocol for constructing a bioartificial hepatic lobe and investigated its biocompatibility. METHODS: The right lateral lobe of porcine liver was decellularized using 0.1% sodium dodecyl sulfate through the right branch of the portal vein. Decellularized lobes were evaluated by histological and biochemical analyses. DNA content was quantified to validate the decellularization protocol. The presence of immunogenic and pathogenic antigens was checked to exclude potential rejection and thrombosis after xenotransplantation. Xeno-reactivity of decellularized tissue against human peripheral blood mononuclear cells was examined. Cytotoxicity was evaluated against hepatocarcinoma cells. Finally, scaffolds were incubated in collagenase for biodegradation testing. RESULTS: The decellularized lobe preserved the three-dimensional architecture, ultrastructure, extracellular matrix components, and vasculature. Scaffolds were almost depleted of DNA in addition to antigenic and pathogenic antigens, which are considered barriers to xenotransplantation. The human immune response against scaffolds was considered non-significant. Our matrices were biocompatible and biodegradable. CONCLUSIONS: We successfully developed a non-cytotoxic, non-immunogenic, and biodegradable porcine hepatic lobe for future liver regeneration and bioengineering.