Nucleosome conformation dictates the histone code.

Histone post-translational modifications (PTMs) play a critical role in chromatin regulation. It has been proposed that these PTMs form localized 'codes' that are read by specialized regions (reader domains) in chromatin-associated proteins (CAPs) to regulate downstream function. Substantial effort has been made to define [CAP: histone PTM] specificities, and thus decipher the histone code and guide epigenetic therapies. However, this has largely been done using the reductive approach of isolated reader domains and histone peptides, which cannot account for any higher-order factors. Here, we show that the [BPTF PHD finger and bromodomain: histone PTM] interaction is dependent on nucleosome context. The tandem reader selectively associates with nucleosomal H3K4me3 and H3K14ac or H3K18ac, a combinatorial engagement that despite being in cis is not predicted by peptides. This in vitro specificity of the BPTF tandem reader for PTM-defined nucleosomes is recapitulated in a cellular context. We propose that regulatable histone tail accessibility and its impact on the binding potential of reader domains necessitates we refine the 'histone code' concept and interrogate it at the nucleosome level.

Obesogens: a unifying theory for the global rise in obesity.

Despite varied treatment, mitigation, and prevention efforts, the global prevalence and severity of obesity continue to worsen. Here we propose a combined model of obesity, a unifying paradigm that links four general models: the energy balance model (EBM), based on calories as the driver of weight gain; the carbohydrate-insulin model (CIM), based on insulin as a driver of energy storage; the oxidation-reduction model (REDOX), based on reactive oxygen species (ROS) as a driver of altered metabolic signaling; and the obesogens model (OBS), which proposes that environmental chemicals interfere with hormonal signaling leading to adiposity. We propose a combined OBS/REDOX model in which environmental chemicals (in air, food, food packaging, and household products) generate false autocrine and endocrine metabolic signals, including ROS, that subvert standard regulatory energy mechanisms, increase basal and stimulated insulin secretion, disrupt energy efficiency, and influence appetite and energy expenditure leading to weight gain. This combined model incorporates the data supporting the EBM and CIM models, thus creating one integrated model that covers significant aspects of all the mechanisms potentially contributing to the obesity pandemic. Importantly, the OBS/REDOX model provides a rationale and approach for future preventative efforts based on environmental chemical exposure reduction.

The Impact of Nasal Intubation on Feeding Outcomes in Neonates Requiring Cardiac Surgery: A Randomized Control Trial.

Neonates who require surgery for congenital heart disease (CHD) frequently have difficulty with oral feeds post-operatively and may require a feeding tube at hospital discharge. The purpose of this study was to determine the effect of oral or nasal intubation route on feeding method at hospital discharge. This was a non-blinded randomized control trial of 62 neonates who underwent surgery for CHD between 2018 and 2021. Infants in the nasal (25 patients) and oral (37 patients) groups were similar in terms of pre-operative risk factors for feeding difficulties including completed weeks of gestational age at birth (39 vs 38 weeks), birthweight (3530 vs 3100 g), pre-operative PO intake (92% vs 81%), and rate of pre-operative intubation (22% vs 28%). Surgical risk factors were also similar including Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category (3.9 vs 4.1), shunt placement (32% vs 41%), cardiopulmonary bypass time (181 vs 177 min), and cross-clamp time (111 vs 105 min). 96% of nasally intubated patients took full oral feeds by discharge as compared with 78% of orally intubated infants (p = 0.05). Nasally intubated infants reach full oral feeds an average of 3 days earlier than their orally intubated peers. In this cohort of patients, nasally intubated infants reach oral feeds more quickly and are less likely to require supplemental tube feeding in comparison to orally intubated peers. Intubation route is a potential modifiable risk factor for oral aversion and appears safe in neonates. The study was approved by the University of Virginia Institutional Review Board for Health Sciences Research and was retrospectively registered on clinicaltrials.gov (NCT05378685) on May 18, 2022.

A test of the 2 × 2 Model of Perfectionistic Pressure in youth sport.

Perfectionistic pressure from coaches and parents is likely to contribute to the development of perfectionism in youth athletes. However, if and how perfectionistic pressure from coaches and parents interact to predict the development of perfectionism is unknown. With this in mind, the present study tested a new model - the 2 × 2 Model of Perfectionistic Pressure - that focuses on the different combinations of perfectionistic pressure youth athletes can experience. Four within-person combinations of perfectionistic pressure are identified and compared: Pure coach pressure (high coach pressure/low parental pressure), pure parental pressure (low coach pressure/high parental pressure), mixed pressure (high coach pressure/high parental pressure), and low pressure (low coach pressure/low parental pressure). To test the model, a sample of 210 youth athletes (M age = 14.68 years) completed measures of perfectionistic strivings, perfectionistic concerns, coach pressure to be perfect, and parental pressure to be perfect. Moderated hierarchical regression and simple slopes analyses revealed that mixed pressure was related to the highest levels of both perfectionistic strivings and perfectionistic concerns. The findings provide initial evidence for the new model and suggests it will be useful in studying the development of perfectionism and other outcomes in sport.

Non-Hormonal Contraception.

While hormonal contraceptives are efficacious and available in several forms for women, perception of safety and concern over side effects are a deterrent for many. Existing non-hormonal contraceptives include permanent sterilization, copper intrauterine devices (IUDs), chemical/physical barriers such as spermicides and condoms, as well as traditional family planning methods including withdrawal and the rhythm method. Individuals who wish to retain their fertility in the future can achieve highest adherence and efficacy with long-acting, reversible contraceptives (LARCs), though there is only one, the copper IUD, that is non-hormonal. As rates of unintended pregnancies remain high with existing contraceptive options, it is becoming increasingly attractive to develop novel pregnancy prevention methods for both women and men. Non-hormonal contraceptives can target a variety of critical reproductive processes discussed here. This review focuses on identified non-hormonal contraceptive targets and subsequent drug candidates in development.

Obesogens and Obesity: State-of-the-Science and Future Directions Summary from a Healthy Environment and Endocrine Disruptors Strategies Workshop.

On September 7 and 8, 2022, Healthy Environment and Endocrine Disruptors Strategies, an Environmental Health Sciences program, convened a scientific workshop of relevant stakeholders involved in obesity, toxicology, or obesogen research to review the state of the science regarding the role of obesogenic chemicals that might be contributing to the obesity pandemic. The workshop's objectives were to examine the evidence supporting the hypothesis that obesogens contribute to the etiology of human obesity; to discuss opportunities for improved understanding, acceptance, and dissemination of obesogens as contributors to the obesity pandemic; and to consider the need for future research and potential mitigation strategies. This report details the discussions, key areas of agreement, and future opportunities to prevent obesity. The attendees agreed that environmental obesogens are real, significant, and a contributor at some degree to weight gain at the individual level and to the global obesity and metabolic disease pandemic at a societal level; moreover, it is at least, in theory, remediable.

An acetylation-mediated chromatin switch governs H3K4 methylation read-write capability.

In nucleosomes, histone N-terminal tails exist in dynamic equilibrium between free/accessible and collapsed/DNA-bound states. The latter state is expected to impact histone N-termini availability to the epigenetic machinery. Notably, H3 tail acetylation (e.g. K9ac, K14ac, K18ac) is linked to increased H3K4me3 engagement by the BPTF PHD finger, but it is unknown if this mechanism has a broader extension. Here, we show that H3 tail acetylation promotes nucleosomal accessibility to other H3K4 methyl readers, and importantly, extends to H3K4 writers, notably methyltransferase MLL1. This regulation is not observed on peptide substrates yet occurs on the cis H3 tail, as determined with fully-defined heterotypic nucleosomes. In vivo, H3 tail acetylation is directly and dynamically coupled with cis H3K4 methylation levels. Together, these observations reveal an acetylation 'chromatin switch' on the H3 tail that modulates read-write accessibility in nucleosomes and resolves the long-standing question of why H3K4me3 levels are coupled with H3 acetylation.

Higher education teachers' digital competencies for a blended future.

Welcome to this special issue, focussing on teachers' digital competencies in Higher Education. The articles in this special issue explore the question of how digital competencies in higher education are conceptualized after the Great Online Transition, during and after the pandemic. A few of the topics addressed in the special issue are: new competency frameworks, the issue of disciplines and artificial intelligence and looks into the future of higher education learning and teaching. In this preface to the special issue, we first present a brief introduction to the context and the problem statement. We then provide a summary of each of the ten papers included in this special issue, we present how they are related and how each article makes a unique contribution to the main goal of the special issue. Finally, the implications are discussed together with suggestions for future research.

The HeDiCom framework: Higher Education teachers' digital competencies for the future.

There is little consensus about the nature of teachers' digital competencies in Higher Education. Moreover, existing digital competence frameworks have largely been developed for teachers in secondary education. In response to this, the current study focuses on developing and validating a framework of digital competencies for teachers in Higher Education. First, a review was conducted to determine the state of digital competence research regarding dimensions and definition of digital competence. In a next step, similarities and differences between existing digital competence frameworks were identified. Based on the outcomes of the review and the framework comparison, a framework was developed in an iterative process through expert meetings with policy makers, experts in the field of educational technology, and validated with practitioners. The new framework includes four dimensions of teachers' digital competencies: (1) Teaching practice, (2) Empowering students for a digital society, (3) Teachers' digital literacy, and (4) Teachers' professional development. The resulting Higher Education Digital Competence (HeDiCom) framework will provide guidance and clearer expectations of teachers' digital competency. Ultimately, improving teachers' digital competencies will contribute to improving the quality of digital competencies of the students.

The feasibility and acceptability of a single-session Acceptance and Commitment Therapy (ACT) intervention to support women self-reporting fear of childbirth in a first pregnancy.

OBJECTIVE: To assess the feasibility and acceptability of a single-session Acceptance and Commitment Therapy intervention to help women manage fear of childbirth during a first pregnancy. DESIGN: A mixed-methods approach including qualitative feedback and pre/post-intervention self-report measures. Pregnant women (14-37 weeks gestation) were recruited via the UK National Health Service and attended a single-session (<3 hours) Acceptance and Commitment Therapy intervention alongside routine antenatal care. Data were analysed using content and statistical analyses. MAIN OUTCOME MEASURES: Fear of childbirth, anxiety and wellbeing were the main outcome measures. Secondary to these, intolerance of uncertainty and valued life domains (e.g. relationships, recreation) as hypothesised mechanisms of change, were also assessed. RESULTS: 33 expressions of interest were received, 21 women signed up, 15 participated, and 11 completed follow-up measures (participation rate: 33%). Findings demonstrated clinical and statistical reductions in fear of childbirth and anxiety alongside positive feedback on the intervention. Intolerance of uncertainty and wellbeing were low at baseline and remained unchanged. CONCLUSION: A single-session Acceptance and Commitment Therapy intervention to manage fear of childbirth is potentially feasible and acceptable. A pilot randomised controlled trial is warranted. Further research should explore efficacy and how Acceptance and Commitment Therapy may reduce perinatal distress.

Child protection training for professionals to improve reporting of child abuse and neglect.

BACKGROUND: Many nations require child-serving professionals to report known or suspected cases of significant child abuse and neglect to statutory child protection or safeguarding authorities. Considered globally, there are millions of professionals who fulfil these roles, and many more who will do so in future. Ensuring they are trained in reporting child abuse and neglect is a key priority for nations and organisations if efforts to address violence against children are to succeed. OBJECTIVES: To assess the effectiveness of training aimed at improving reporting of child abuse and neglect by professionals and to investigate possible components of effective training interventions. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, 18 other databases, and one trials register up to 4 June 2021. We also handsearched reference lists, selected journals, and websites, and circulated a request for studies to researchers via an email discussion list. SELECTION CRITERIA: All randomised controlled trials (RCTs), quasi-RCTs, and controlled before-and-after studies examining the effects of training interventions for qualified professionals (e.g. teachers, childcare professionals, doctors, nurses, and mental health professionals) to improve reporting of child abuse and neglect, compared with no training, waitlist control, or alternative training (not related to child abuse and neglect). DATA COLLECTION AND ANALYSIS: We used methodological procedures described in the Cochrane Handbook for Systematic Reviews of Interventions. We synthesised training effects in meta-analysis where possible and summarised findings for primary outcomes (number of reported cases of child abuse and neglect, quality of reported cases, adverse events) and secondary outcomes (knowledge, skills, and attitudes towards the reporting duty). We used the GRADE approach to rate the certainty of the evidence. MAIN RESULTS: We included 11 trials (1484 participants), using data from 9 of the 11 trials in quantitative synthesis. Trials took place in high-income countries, including the USA, Canada, and the Netherlands, with qualified professionals. In 8 of the 11 trials, interventions were delivered in face-to-face workshops or seminars, and in 3 trials interventions were delivered as self-paced e-learning modules. Interventions were developed by experts and delivered by specialist facilitators, content area experts, or interdisciplinary teams. Only 3 of the 11 included studies were conducted in the past 10 years. Primary outcomes Three studies measured the number of cases of child abuse and neglect via participants' self-report of actual cases reported, three months after training. The results of one study (42 participants) favoured the intervention over waitlist, but the evidence is very uncertain (standardised mean difference (SMD) 0.81, 95% confidence interval (CI) 0.18 to 1.43; very low-certainty evidence). Three studies measured the number of cases of child abuse and neglect via participants' responses to hypothetical case vignettes immediately after training. A meta-analysis of two studies (87 participants) favoured training over no training or waitlist for training, but the evidence is very uncertain (SMD 1.81, 95% CI 1.30 to 2.32; very low-certainty evidence).  We identified no studies that measured the number of cases of child abuse and neglect via official records of reports made to child protection authorities, or adverse effects of training. Secondary outcomes Four studies measured professionals' knowledge of reporting duty, processes, and procedures postintervention. The results of one study (744 participants) may favour the intervention over waitlist for training (SMD 1.06, 95% CI 0.90 to 1.21; low-certainty evidence). Four studies measured professionals' knowledge of core concepts in all forms of child abuse and neglect postintervention. A meta-analysis of two studies (154 participants) favoured training over no training, but the evidence is very uncertain (SMD 0.68, 95% CI 0.35 to 1.01; very low-certainty evidence). Three studies measured professionals' knowledge of core concepts in child sexual abuse postintervention. A meta-analysis of these three studies (238 participants) favoured training over no training or waitlist for training, but the evidence is very uncertain (SMD 1.44, 95% CI 0.43 to 2.45; very low-certainty evidence). One study (25 participants) measured professionals' skill in distinguishing reportable and non-reportable cases postintervention. The results favoured the intervention over no training, but the evidence is very uncertain (SMD 0.94, 95% CI 0.11 to 1.77; very low-certainty evidence). Two studies measured professionals' attitudes towards the duty to report child abuse and neglect postintervention. The results of one study (741 participants) favoured the intervention over waitlist, but the evidence is very uncertain (SMD 0.61, 95% CI 0.47 to 0.76; very low-certainty evidence). AUTHORS' CONCLUSIONS: The studies included in this review suggest there may be evidence of improvements in training outcomes for professionals exposed to training compared with those who are not exposed. However, the evidence is very uncertain. We rated the certainty of evidence as low to very low, downgrading due to study design and reporting limitations. Our findings rest on a small number of largely older studies, confined to single professional groups. Whether similar effects would be seen for a wider range of professionals remains unknown. Considering the many professional groups with reporting duties, we strongly recommend further research to assess the effectiveness of training interventions, with a wider range of child-serving professionals. There is a need for larger trials that use appropriate methods for group allocation, and statistical methods to account for the delivery of training to professionals in workplace groups.

Obesity III: Obesogen assays: Limitations, strengths, and new directions.

There is increasing evidence of a role for environmental contaminants in disrupting metabolic health in both humans and animals. Despite a growing need for well-understood models for evaluating adipogenic and potential obesogenic contaminants, there has been a reliance on decades-old in vitro models that have not been appropriately managed by cell line providers. There has been a quick rise in available in vitro models in the last ten years, including commercial availability of human mesenchymal stem cell and preadipocyte models; these models require more comprehensive validation but demonstrate real promise in improved translation to human metabolic health. There is also progress in developing three-dimensional and co-culture techniques that allow for the interrogation of a more physiologically relevant state. While diverse rodent models exist for evaluating putative obesogenic and/or adipogenic chemicals in a physiologically relevant context, increasing capabilities have been identified for alternative model organisms such as Drosophila, C. elegans, zebrafish, and medaka in metabolic health testing. These models have several appreciable advantages, including most notably their size, rapid development, large brood sizes, and ease of high-resolution lipid accumulation imaging throughout the organisms. They are anticipated to expand the capabilities of metabolic health research, particularly when coupled with emerging obesogen evaluation techniques as described herein.

Obesity I: Overview and molecular and biochemical mechanisms.

Obesity is a chronic, relapsing condition characterized by excess body fat. Its prevalence has increased globally since the 1970s, and the number of obese and overweight people is now greater than those underweight. Obesity is a multifactorial condition, and as such, many components contribute to its development and pathogenesis. This is the first of three companion reviews that consider obesity. This review focuses on the genetics, viruses, insulin resistance, inflammation, gut microbiome, and circadian rhythms that promote obesity, along with hormones, growth factors, and organs and tissues that control its development. It shows that the regulation of energy balance (intake vs. expenditure) relies on the interplay of a variety of hormones from adipose tissue, gastrointestinal tract, pancreas, liver, and brain. It details how integrating central neurotransmitters and peripheral metabolic signals (e.g., leptin, insulin, ghrelin, peptide YY3-36) is essential for controlling energy homeostasis and feeding behavior. It describes the distinct types of adipocytes and how fat cell development is controlled by hormones and growth factors acting via a variety of receptors, including peroxisome proliferator-activated receptor-gamma, retinoid X, insulin, estrogen, androgen, glucocorticoid, thyroid hormone, liver X, constitutive androstane, pregnane X, farnesoid, and aryl hydrocarbon receptors. Finally, it demonstrates that obesity likely has origins in utero. Understanding these biochemical drivers of adiposity and metabolic dysfunction throughout the life cycle lends plausibility and credence to the "obesogen hypothesis" (i.e., the importance of environmental chemicals that disrupt these receptors to promote adiposity or alter metabolism), elucidated more fully in the two companion reviews.

Obesity II: Establishing causal links between chemical exposures and obesity.

Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.

Effects of Injection Volume and Route of Administration on Dolutegravir In Situ Forming Implant Pharmacokinetics.

Due to the versatility of the in situ forming implant (ISFI) drug delivery system, it is crucial to understand the effects of formulation parameters for clinical translation. We utilized ultrasound imaging and pharmacokinetics (PK) in mice to understand the impact of administration route, injection volume, and drug loading on ISFI formation, degradation, and drug release in mice. Placebo ISFIs injected subcutaneously (SQ) with smaller volumes (40 µL) exhibited complete degradation within 30-45 days, compared to larger volumes (80 µL), which completely degraded within 45-60 days. However, all dolutegravir (DTG)-loaded ISFIs along the range of injection volumes tested (20-80 µL) were present at 90 days post-injection, suggesting that DTG can prolong ISFI degradation. Ultrasound imaging showed that intramuscular (IM) ISFIs flattened rapidly post administration compared to SQ, which coincides with the earlier Tmax for drug-loaded IM ISFIs. All mice exhibited DTG plasma concentrations above four times the protein-adjusted 90% inhibitory concentration (PA-IC90) throughout the entire 90 days of the study. ISFI release kinetics best fit to zero order or diffusion-controlled models. When total administered dose was held constant, there was no statistical difference in drug exposure regardless of the route of administration or number of injections.

Targeting the ERK mitogen-activated protein kinase cascade for the treatment of KRAS-mutant pancreatic cancer.

Mutational activation of the KRAS oncogene is found in ~95% of pancreatic ductal adenocarcinoma (PDAC), the major form of pancreatic cancer. With substantial experimental evidence that continued aberrant KRAS function is essential for the maintenance of PDAC tumorigenic growth, the National Cancer Institute has identified the development of effective anti-KRAS therapies as one of four major initiatives for pancreatic cancer research. The recent clinical success in the development of an anti-KRAS therapy targeting one specific KRAS mutant (G12C) supports the significant potential impact of anti-KRAS therapies. However, KRASG12C mutations comprise only 2% of KRAS mutations in PDAC. Thus, there remains a dire need for additional therapeutic approaches for targeting the majority of KRAS-mutant PDAC. Among the different directions currently being pursued for anti-KRAS drug development, one of the most promising involves inhibitors of the key KRAS effector pathway, the three-tiered RAF-MEK-ERK mitogen-activated protein kinase (MAPK) cascade. We address the promises and challenges of targeting ERK MAPK signaling as an anti-KRAS therapy for PDAC. In particular, we also summarize the key role of the MYC transcription factor and oncoprotein in supporting ERK-dependent growth of KRAS-mutant PDAC.

A trivalent nucleosome interaction by PHIP/BRWD2 is disrupted in neurodevelopmental disorders and cancer.

Mutations in the PHIP/BRWD2 chromatin regulator cause the human neurodevelopmental disorder Chung-Jansen syndrome, while alterations in PHIP expression are linked to cancer. Precisely how PHIP functions in these contexts is not fully understood. Here we demonstrate that PHIP is a chromatin-associated CRL4 ubiquitin ligase substrate receptor and is required for CRL4 recruitment to chromatin. PHIP binds to chromatin through a trivalent reader domain consisting of a H3K4-methyl binding Tudor domain and two bromodomains (BD1 and BD2). Using semisynthetic nucleosomes with defined histone post-translational modifications, we characterize PHIPs BD1 and BD2 as respective readers of H3K14ac and H4K12ac, and identify human disease-associated mutations in each domain and the intervening linker region that likely disrupt chromatin binding. These findings provide new insight into the biological function of this enigmatic chromatin protein and set the stage for the identification of both upstream chromatin modifiers and downstream targets of PHIP in human disease.

Separation and Characterization of Endogenous Nucleosomes by Native Capillary Zone Electrophoresis-Top-Down Mass Spectrometry.

We report a novel platform [native capillary zone electrophoresis-top-down mass spectrometry (nCZE-TDMS)] for the separation and characterization of whole nucleosomes, their histone subunits, and post-translational modifications (PTMs). As the repeating unit of chromatin, mononucleosomes (Nucs) are an ∼200 kDa complex of DNA and histone proteins involved in the regulation of key cellular processes central to human health and disease. Unraveling the covalent modification landscape of histones and their defined stoichiometries within Nucs helps to explain epigenetic regulatory mechanisms. In nCZE-TDMS, online Nuc separation is followed by a three-tier tandem MS approach that measures the intact mass of Nucs, ejects and detects the constituent histones, and fragments to sequence the histone. The new platform was optimized with synthetic Nucs to significantly reduce both sample requirements and cost compared to direct infusion. Limits of detection were in the low-attomole range, with linearity of over ∼3 orders of magnitude. The nCZE-TDMS platform was applied to endogenous Nucs from two cell lines distinguished by overexpression or knockout of histone methyltransferase NSD2/MMSET, where analysis of constituent histones revealed changes in histone abundances over the course of the CZE separation. We are confident the nCZE-TDMS platform will help advance nucleosome-level research in the fields of chromatin and epigenetics.