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Abstract Introduction Mental health problems are a considerable public health issue and spending time in nature has been promoted as a way to access a range of psychological benefits leading to the development of nature‐based interventions for people with severe and enduring mental health problems. Less, however, is understood about the potential benefits and efficacy of day‐to‐day routine access to outdoor green and blue spaces for mental health service users. Methods Using a mixed‐methods design between April and October 2021, we explored the benefits and barriers to spending time outdoors with a purposive sample of mental health service users (N = 11) using qualitative interviews and an online general population survey (N = 1791). Qualitative evidence highlighted the restorative benefits of nature and identified a number of barriers associated with fears around personal safety, social anxiety, fatigue and lack of motivation. COVID‐19 had also restricted access to green and blue spaces. Having social contact and support encouraged people to spend time outdoors. In the quantitative survey, self‐report and standardised measures (the Patient Health Questionnaire and the Warwick–Edinburgh Wellbeing Scale) were used to assess past and current mental wellbeing. Findings Statistically significant differences were found between wellbeing and the use of green and blue spaces. Those with mental health problems spent time outdoors because they: felt guilty; wanted to reduce their anxiety; or rely on someone for encouragement. Those without mental health problems endorsed more positively framed reasons including relaxation, improving physical health or getting exercise. Barriers for people with mental health problems involved safety concerns, feeling anxious and having a poor self‐image. These findings give insight into motivations for an outdoor activity to help inform the design of public mental health interventions. Conclusion Further work is required to improve access and safety to promote the benefits of green and blue spaces for everyone. Patient or Public Contribution The research team included expert experienced researchers with a mental health service provider (Praxis Care) and they were involved in the development of the research idea, funding application, design, data collection, analysis, writing up and dissemination activities.

Plain English summary Making your own decisions is important. There are disabled people who need support to make some decisions. Supporting disabled people to make decisions is needed so that they are not excluded from society. However, the evidence is limited on disabled people’s experiences of how best to support decision-making. This article will explore the experiences of four researchers with mental health problems or an intellectual disability who worked with other researchers to conduct a project on how people have, or have not been, supported to make their own decisions. These researchers are called peer researchers. The peer researchers interviewed 21 people with mental health problems and 20 people with an intellectual disability. These interviews were conducted in order to gain a detailed understanding of the experiences and preferences for how decision-making should be supported. Blogs written by the peer researchers, discussions in team meetings and a workshop at the end of the study enabled the peer researchers to reflect on their experiences. The peer researchers reported a number of positive effects of being involved in the research project which included improvements in skills and self-confidence. The peer researchers’ involvement challenged assumptions about the inability of people with an intellectual disability and/or mental health problems to participate in a research project whilst also highlighting the importance of training for all team members.

Plain English summary Since the 1970’s, there has been a shift from research on disabled people to research with disabled people. This is often referred to as co-produced research. Co-production has a wide definition but includes disabled people working with academics to produce research and outcomes which neither group could achieve by working in isolation. This paper presents the co-production methodology used to conduct a research project called ‘Getting our Voices Heard’. This project, sought to find the best way to get the voices of people with a learning disability heard inpolicy development in the UK. We explain how this research was carried out, using a co-produced participatory design. We established a research team with professional researchers from a university, who worked with peer researchers. Peer researchers are people who have lived experience of the issue being studied. In this project, we worked with six peer researchers who all had a learning disability. The experiences of the peer researchers, and ways in which the peer researchers were involved at each stage of the project are discussed. The peer researchers described feeling positive about their role and felt involved. We show that working together is important and recommend that additional time and resources are essential for this joint working.

Plain English summary The aim of this study was to gather information to help us understand the experience of participants’ undertaking a research course called ‘Getting Involved in Research’. A group of individuals including those with lived experience of health and social care services, academics, community and voluntary sector workers and a representative from the Department of Health in Northern Ireland worked together to develop a course to encourage and support people to engage with research. The ‘Getting Involved in Research’, course was designed to provide an understandable introduction to research for those people with lived experience of health and social care. We did this because research in health and social care sector should involve the patients and public who it is intended to help. The evaluation of the course had two distinct phases; we asked course participants to complete a survey before and after the course (pre- and post-course survey) and also asked them to complete a journal reflecting on their experiences after each lecture. This paper gives an overview of the profile of course participants and their responses to the survey questions. The survey answers were analysed using an approach to analysing information which encourages involvement from people with a range of experience of research methods, (known as Participatory Theme Elicitation). Thirty-five participants in total participated in ‘Getting Involved in Research’. Age ranges varied from 19 to 73 years old. Participants were predominately female (n = 24), five males participated (n = 5) and there was one participant who identified as non-binary (n = 1). Participants in ‘Getting Involved in Research’ reported that the content of the course was relevant, encouraged awareness of research methods and encourage their future involvement in research.

Abstract Background Upregulation of estrogen receptor beta (ERβ) in breast cancer cells is associated with epithelial maintenance, decreased proliferation and invasion, and a reduction in the expression of the receptor has been observed in invasive breast tumors. However, proof of an association between loss of ERβ and breast carcinogenesis is still missing. Methods To study the role of ERβ in breast oncogenesis, we generated mouse conditional mutants with specific inactivation of ERβ and p53 in the mammary gland epithelium. For epithelium-specific knockout of ERβ and p53, ERβ F/F and p53 F/F mice were crossed to transgenic mice that express the Cre recombinase under the control of the human keratin 14 promoter. Results Somatic loss of ERβ significantly accelerated formation of p53-deficient mammary tumors. Loss of the receptor also resulted in the development of less differentiated carcinomas with stronger spindle cell morphology and decreased expression of luminal epithelial markers. Conclusions Our results show that synergism between ERβ and p53 inactivation functions to determine important aspects of breast oncogenesis and cancer progression.

Background: Literature reveals that guided play promotes the development of visuospatial abilities essential for learning to read, write and do mathematics. However, most of these findings have focused on older children who are already literate, and the tests and the instruments used were designed for children in Western contexts. Aim: As there is little data on the development of visuospatial abilities in pre-literate children in African contexts, this study set out to explore the effects of using a guided block play intervention on the development of these abilities in pre-literate children. Setting: The study was carried out in two classrooms (one experimental and the other comparative) in each of two schools, one in South Africa and one in Kenya. Methods: The study used a pre- and post-test, quasi-experimental, mixed-methods approach. The intervention and test used, namely, the Visual Perception Aspects Test, were designed and validated in African contexts. Results: The data revealed that using the 6 Brick Duplo Block guided play approach statistically significantly accelerated the development of visuospatial abilities in pre-literate children in the experimental groups over those in the control groups (no intervention). The data also revealed that the greatest improvements were made among children who had few prior opportunities to engage in guided play using physical manipulatives. Conclusion: The overall findings of the study suggest that the development of aspects of visuospatial perception is accelerated when teachers use this approach to facilitate guided play. This finding has implications for promoting the development of reading, writing and numeracy skills in pre-literate children.

Thyroid hormone receptors (TRs) are responsible for mediating thyroid hormone (T3 and T4) actions at a cellular level. They belong to the nuclear receptor (NR) superfamily and execute their main functions inside the cell nuclei as hormone-regulated transcription factors. These receptors also exhibit so-called “non-classic” actions, for which other cellular proteins, apart from coregulators inside nuclei, regulate their activity. Aiming to find alternative pathways of TR modulation, we searched for interacting proteins and found that PDIA1 interacts with TRβ in a yeast two-hybrid screening assay. The functional implications of PDIA1—TR interactions are still unclear; however, our co-immunoprecipitation (co-IP) and fluorescence assay results showed that PDI was able to bind both TR isoforms in vitro. Moreover, T3 appears to have no important role in these interactions in cellular assays, where PDIA1 was able to regulate transcription of TRα and TRβ-mediated genes in different ways depending on the promoter region and on the TR isoform involved. Although PDIA1 appears to act as a coregulator, it binds to a TR surface that does not interfere with coactivator binding. However, the TR:PDIA1 complex affinity and activation are different depending on the TR isoform. Such differences may reflect the structural organization of the PDIA1:TR complex, as shown by models depicting an interaction interface with exposed cysteines from both proteins, suggesting that PDIA1 might modulate TR by its thiol reductase/isomerase activity.

Loss-of-function mutation V290M in the ligand-binding domain of the peroxisome proliferator activated receptor γ (PPARγ) is associated with a ligand resistance syndrome (PLRS), characterized by partial lipodystrophy and severe insulin resistance. In this data article we discuss an X-ray diffraction dataset that yielded the structure of PPARγ LBD V290M mutant refined at 2.3 Å resolution, that allowed building of 3D model of the receptor mutant with high confidence and revealed continuous well-defined electron density for the partial agonist diclofenac bound to hydrophobic pocket of the PPARγ. These structural data provide significant insights into molecular basis of PLRS caused by V290M mutation and are correlated with the receptor disability of rosiglitazone binding and increased affinity for corepressors. Furthermore, our structural evidence helps to explain clinical observations which point out to a failure to restore receptor function by the treatment with a full agonist of PPARγ, rosiglitazone. Keywords: Peroxisome proliferator activated receptor γ, Nuclear receptors, X-ray structureç ligand resistance syndrome

The functional conversion of white adipose tissue (WAT) into a tissue with brown adipose tissue (BAT)-like activity, often referred to as “browning,” represents an intriguing strategy for combating obesity and metabolic disease. We demonstrate that thyroid hormone receptor (TR) activation by a synthetic agonist markedly induces a program of adaptive thermogenesis in subcutaneous WAT that coincides with a restoration of cold tolerance to cold-intolerant mice. Distinct from most other browning agents, pharmacological TR activation dissociates the browning of WAT from activation of classical BAT. TR agonism also induces the browning of white adipocytes in vitro, indicating that TR-mediated browning is cell autonomous. These data establish TR agonists as a class of browning agents, implicate the TRs in the browning of WAT, and suggest a profound pharmacological potential of this action.

Thyroid hormone (TH) receptors (TRs α and β) are homologous ligand-dependent transcription factors (TFs). While the TRs display distinct actions in development, metabolic regulation and other processes, comparisons of TRα and TRβ dependent gene regulation mostly reveal similar mechanisms of action and few TR subtype specific genes. Here, we show that TRα predominates in multipotent human adipose derived stem cells (hADSC) whereas TRβ is expressed at lower levels and is upregulated during hADSC differentiation. The TRs display several unusual properties in parental hADSC. First, TRs display predominantly cytoplasmic intracellular distribution and major TRα variants TRα1 and TRα2 colocalize with mitochondria. Second, knockdown experiments reveal that endogenous TRs influence hADSC cell morphology and expression of hundreds of genes in the absence of hormone, but do not respond to exogenous TH. Third, TRα and TRβ affect hADSC in completely distinct ways; TRα regulates cell cycle associated processes while TRβ may repress aspects of differentiation. TRα splice variant specific knockdown reveals that TRα1 and TRα2 both contribute to TRα-dependent gene expression in a gene specific manner. We propose that TRs work in a non-canonical and hormone independent manner in hADSC and that prominent subtype-specific activities emerge in the context of these unusual actions.

This study is to track the subject matter knowledge of and misconception about Teaching Games for Understanding (TGfU) of fourth year undergraduate pre-service teachers‟ physical education majors at an Australian university. The test of reliability on misconception scale are subjected to a Rasch analysis (KR-20 = .52) which consists of 20 dichotomous questions with true/false answers. Analyses of the data reveal that students achieve a credit on subject matter knowledge and attain four misconceptions about TGfU. There is a significant (p < 0.05) difference in the scores for subject matter knowledge and concepts of TGfU through paired samples t test. These results imply that subject matter knowledge does have an effect on students‟ concepts of TGfU but with very low relationship (r(53 = .19, p < 0.05). The implication of content knowledge to teaching is to resist the pre-concept or misconception of the subject matter. If pre-service teachers are to improve the quality of teaching and learning in content areas, he or she needs to possess a deep understanding of games both within and across categories in TGfU. Misconceptions tend to be very resistant to instruction because learning entails replacing or radically reorganizing student knowledge. This puts teachers in the very challenging position of needing to bring about significant conceptual change in student knowledge. Therefore pre-service teachers must know the subject matter they teach and their performance will be determined by the depth of their content knowledge in relation to teaching, making this an essential component to their teaching practice. Teachers must know the subject they teach and this is important to teacher competency.

In the 2015 general election, the Conservative party did not just win an overall parliamentary majority against expectations, but they also increased their national share of the vote and secured additional seats in local government. The article examines the long and short term campaigns and contrasts the 2010 campaign with the one in 2015 to explain their success. It highlights how the Conservatives were able to spin a convincing narrative of Labour economic incompetence and welfare profligacy and capitalise on their opponents’ inner conflicts and voters’ fears of a Labour-SNP coalition. The article argues that their victory is also due to their command of valence issues and their effective targeting of marginal seats.

This study investigated the effects of a HIV/AIDS module on teachers' sense of self-efficacy regarding their ability to bring about behaviours in their learners which contribute to responsible living and a reduction of the spread of HIV in their communities. The sample was 128 in-service teachers studying in nine different centres in three South African provinces in their second year of a parttime degree in education. A modified Science Teaching Efficacy Belief Instrument (STEBI) was used to generate quantitative data, while semi-structured individual and focus group interviews provided qualitative data. Statistical analyses (ANOVA and MANOVA) revealed statistically significant differences between the participants pre- and post-test self-efficacy scores. Interview data suggested that improved confidence enabled the teachers to gain a better understanding of cultural barriers to HIV/AIDS education and the impediments to developing an effective HIV/AIDS policy in their schools. The study also highlighted the importance of leadership from school management for the successful adoption and implementation of an effective HIV/AIDS policy in schools. Enhanced confidence is noted as a motivating factor for teacher participation in community efforts to support those affected by HIV/AIDS.

The Department of Education in South Africa advocates collaborative and constructivist learning; however, observations indicate that little discussion occurs in most multilingual mathematics classes. In this paper we draw on a pilot study set in the Eastern Cape where teachers were introduced to the theory and practice of exploratory talk, and then tasked to perform an action research project on introducing discussion in their own multilingual mathematics classrooms. The results of the study suggest some successes in terms of teachers initiating exploratory talk and highlight the fact that these successes were only achieved where code switching between English and isiXhosa formed an integral part of the process.

For the last decade research on teachers’ beliefs has made a distinction between mathematics teachers’ professed and attributed beliefs (practice) and studies have either found some or no correlation between the two. In this paper we investigate the beliefs and practices of a novice teacher and conclude that inconsistency between beliefs and practices may be an observer’s perspective that is not necessarily shared by the teacher, and that the view that there is a possible disjuncture does not do justice to the complexity of the practitioner’s tasks nor to the rapidly changing contexts and situations that may occur within a single lesson.

The inquiry-based Family Maths professional development programme, offered by the Nelson Mandela Metropolitan University, attempts not only to support the transformative education practices targeted by the South African National Department of Education, but also to extend them beyond the school walls to the community at large. This study investigates the extent to which this programme develops facilitators’ ability to implement inquiry-based learning. The research undertaken uses both qualitative and quantitative methods in an empirical study of 39 facilitators. The facilitators’ inquiry beliefs and ability to implement inquiry learning was measured by means of questionnaires, observation schedules and interviews. Data generated by the study reveal that both the facilitators’ understanding and practice of inquiry improved as they progressed through the novice, intermediate and veteran categories of the Family Maths professional development programme.

Thyroid hormone receptor (TR) agonists have been proposed as therapeutic agents to treat non-alcoholic fatty liver disease (NAFLD) and insulin resistance. We investigated the ability of the TR agonists GC-1 and KB2115 to reduce hepatic steatosis in ob/ob mice. Both compounds markedly reduced hepatic triglyceride levels and ameliorated hepatic steatosis. However, the amelioration of fatty liver was not sufficient to improve insulin sensitivity in these mice and reductions in hepatic triglycerides did not correlate with improvements in insulin sensitivity or glycemic control. Instead, the effects of TR activation on glycemia varied widely and were found to depend upon the time of treatment as well as the compound and dosage used. Lower doses of GC-1 were found to further impair glycemic control, while a higher dose of the same compound resulted in substantially improved glucose tolerance and insulin sensitivity, despite all doses being equally effective at reducing hepatic triglyceride levels. Improvements in glycemic control and insulin sensitivity were observed only in treatments that also increased body temperature, suggesting that the induction of thermogenesis may play a role in mediating these beneficial effects. These data illustrate that the relationship between TR activation and insulin sensitivity is complex and suggests that although TR agonists may have value in treating NAFLD, their effect on insulin sensitivity must also be considered.

The androgen receptor (AR) surface-directed antagonist MJC13 inhibits AR function and proliferation of prostate cancer (PC) cells. These effects are related to arrest of an AR/chaperone complex in the cytoplasm. Here, we compared MJC13 and classic AR antagonists such as flutamide and bicalutamide. Microarray analysis and confirmatory qRT-PCR reveals that MJC13 and flutamide inhibit dihydrotestosterone (DHT)-dependent genes in LNCaP PC cells. Both compounds are equally effective on a genome wide basis and as effective as second generation AR antagonists (MDV3100, ARN-509) at selected genes. MJC13 inhibits AR binding to the prostate specific antigen (PSA) promoter more strongly than flutamide, consistent with different mechanisms of action. Examination of efficacy of MJC13 in conditions that reflect aspects castrate resistant prostate cancer (CRPC) reveals that it inhibits flutamide activation of an AR mutant (ART877A) that emerges during flutamide withdrawal syndrome, but displays greatly restricted gene-specific activity in 22Rv1 cells that express a constitutively active truncated AR and is inactive against glucocorticoid receptor (GR), which can co-opt androgen-dependent signaling networks in CRPC. Importantly, MJC13 inhibits AR interactions with SRC2 and β-catenin in the nucleus and, unlike flutamide, strongly inhibits amplification of AR activity obtained with transfected SRC2 and β-catenin. MJC13 also inhibits DHT and β-catenin-enhanced cell division in LNCaP cells. Thus, a surface-directed antagonist can block AR activity in some conditions in which a classic antagonist fails and may display utility in particular forms of CRPC.

The estrogen receptor (ER) β variant ERβ2 is expressed in aggressive castration-resistant prostate cancer and has been shown to correlate with decreased overall survival. Genome-wide expression analysis after ERβ2 expression in prostate cancer cells revealed that hypoxia was an overrepresented theme. Here we show that ERβ2 interacts with and stabilizes HIF-1α protein in normoxia, thereby inducing a hypoxic gene expression signature. HIF-1α is known to stimulate metastasis by increasing expression of Twist1 and increasing vascularization by directly activating VEGF expression. We found that ERβ2 interacts with HIF-1α and piggybacks to the HIF-1α response element present on the proximal Twist1 and VEGF promoters. These findings suggest that at least part of the oncogenic effects of ERβ2 is mediated by HIF-1α and that targeting of this ERβ2 - HIF-1α interaction may be a strategy to treat prostate cancer.

FKBP52 and β-catenin have emerged in recent years as attractive targets for prostate cancer treatment. β-catenin interacts directly with the androgen receptor (AR) and has been characterized as a co-activator of AR-mediated transcription. FKBP52 is a positive regulator of AR in cellular and whole animal models and is required for the development of androgen-dependent tissues. We previously characterized an AR inhibitor termed MJC13 that putatively targets the AR BF3 surface to specifically inhibit FKBP52-regulated AR signaling. Predictive modeling suggests that β-catenin interacts with the AR hormone binding domain on a surface that overlaps with BF3. Here we demonstrate that FKBP52 and β-catenin interact directly in vitro and act in concert to promote a synergistic up-regulation of both hormone-independent and -dependent AR signaling. Our data demonstrate that FKBP52 promotes β-catenin interaction with AR and is required for β-catenin co-activation of AR activity in prostate cancer cells. MJC13 effectively blocks β-catenin interaction with the AR LBD and the synergistic up-regulation of AR by FKBP52 and β-catenin. Our data suggest that co-regulation of AR by FKBP52 and β-catenin does not require FKBP52 PPIase catalytic activity, nor FKBP52 binding to Hsp90. However, the FKBP52 proline-rich loop that overhangs the PPIase pocket is critical for synergy.

A number of researchers in mathematical education assert that the instruction in geometry offered in South African schools is inadequate and that traditional teaching strategies do little to promote teachers understandings of their learners’ levels of mathematical thought. Van Hiele specifically states that the inability of many teachers to match instruction with their learners’ levels of geometrical understanding is a contributing factor to their failure to promote meaningful understandings in this topic. This study investigated whether a sample of grade seven learners in previously disadvantaged primary schools met both the assessment criteria for geometry as stated by the South African Revised National Curriculum Statement and the implied Van Hiele thinking levels. The data generated suggest that none of the 30 learners who participated in this study had attained these requirements and that language competency in general is a barrier to the attainment of higher levels of understanding amongst this group of second-language learners. It is suggested that not only Van Hiele Levels and Assessment Standards, but also learners’ cultural background and their specific use of words in the vernacular context, need to be taken into consideration by teachers when developing learning programmes. Possible strategies to meet these requirements are suggested.

Various studies have shown that what teachers consider to be optimal ways of teaching mathematics is influenced by their beliefs about the nature of mathematics, and that it is advantageous to determine teachers’ conceptions of the nature of mathematics before developing curriculum interventions. With the imminent introduction of Mathematical Literacy in the FET phase in South Africa this study provides a snapshot of beliefs of teachers in the Eastern Cape, South Africa. Various methods were employed to stimulate teachers to both reflect on their beliefs and to make them explicit. A questionnaire was administered to 339 in-service teachers in urban and rural areas of the Eastern Cape. A sample of ninety-five of these teachers completed a second questionnaire based on videotapes of lessons recorded during the TIMSS (1995) study that they had viewed. These teachers also ranked their own teaching on a continuum ranging from traditional to constructivist approaches and provided explanations for their ranking. A further sub-sample of thirty-six teachers participated in individual interviews, which explored their perceptions of the nature of mathematics and their own teaching practice. In order to investigate whether these beliefs were mirrored in practice, four teachers were observed and videotaped in their classrooms. The data generated by this study suggest that the participating teachers’ espoused beliefs of the nature of mathematics tended to be innovative, and correlated with innovative views of teaching and learning; however these views were often not reflected in their practice. The implications that the apparent inability of teachers to translate their beliefs into practice have for the introduction of a contextual, problem-based Mathematical Literacy curriculum for teachers is explored.

Nuclear receptors (NRs) are an important group of ligand-dependent transcriptional factors. Presently, no natural or synthetic ligand has been identified for a large group of orphan NRs. Small molecules to target these orphan NRs will provide unique resources for uncovering regulatory systems that impact human health and to modulate these pathways with drugs. The orphan NR tailless (TLX, NR2E1), a transcriptional repressor, is a major player in neurogenesis and Neural Stem Cell (NSC) derived brain tumors. No chemical probes that modulate TLX activity are available, and it is not clear whether TLX is druggable. To assess TLX ligand binding capacity, we created homology models of the TLX ligand binding domain (LBD). Results suggest that TLX belongs to an emerging class of NRs that lack LBD helices α1 and α2 and that it has potential to form a large open ligand binding pocket (LBP). Using a medium throughput screening strategy, we investigated direct binding of 20,000 compounds to purified human TLX protein and verified interactions with a secondary (orthogonal) assay. We then assessed effects of verified binders on TLX activity using luciferase assays. As a result, we report identification of three compounds (ccrp1, ccrp2 and ccrp3) that bind to recombinant TLX protein with affinities in the high nanomolar to low micromolar range and enhance TLX transcriptional repressive activity. We conclude that TLX is druggable and propose that our lead compounds could serve as scaffolds to derive more potent ligands. While our ligands potentiate TLX repressive activity, the question of whether it is possible to develop ligands to de-repress TLX activity remains open.

Thyroid hormone (TH) receptors (TRs) play central roles in metabolism and are major targets for pharmaceutical intervention. Presently, however, there is limited information about genome wide localizations of TR binding sites. Thus, complexities of TR genomic distribution and links between TRβ binding events and gene regulation are not fully appreciated. Here, we employ a BioChIP approach to capture TR genome-wide binding events in a liver cell line (HepG2). Like other NRs, TRβ appears widely distributed throughout the genome. Nevertheless, there is striking enrichment of TRβ binding sites immediately 5' and 3' of transcribed genes and TRβ can be detected near 50% of T3 induced genes. In contrast, no significant enrichment of TRβ is seen at negatively regulated genes or genes that respond to unliganded TRs in this system. Canonical TRE half-sites are present in more than 90% of TRβ peaks and classical TREs are also greatly enriched, but individual TRE organization appears highly variable with diverse half-site orientation and spacing. There is also significant enrichment of binding sites for TR associated transcription factors, including AP-1 and CTCF, near TR peaks. We conclude that T3-dependent gene induction commonly involves proximal TRβ binding events but that far-distant binding events are needed for T3 induction of some genes and that distinct, indirect, mechanisms are often at play in negative regulation and unliganded TR actions. Better understanding of genomic context of TR binding sites will help us determine why TR regulates genes in different ways and determine possibilities for selective modulation of TR action.

Sirtuin 1 (SIRT1) NAD(+)-dependent deacetylase regulates energy metabolism by modulating expression of genes involved in gluconeogenesis and other liver fasting responses. While many effects of SIRT1 on gene expression are mediated by deacetylation and activation of peroxisome proliferator activated receptor coactivator α (PGC-1α), SIRT1 also binds directly to DNA bound transcription factors, including nuclear receptors (NRs), to modulate their activity. Since thyroid hormone receptor β1 (TRβ1) regulates several SIRT1 target genes in liver and interacts with PGC-1α, we hypothesized that SIRT1 may influence TRβ1. Here, we confirm that SIRT1 cooperates with PGC-1α to enhance response to triiodothyronine, T3. We also find, however, that SIRT1 stimulates TRβ1 activity in a manner that is independent of PGC-1α but requires SIRT1 deacetylase activity. SIRT1 interacts with TRβ1 in vitro, promotes TRβ1 deacetylation in the presence of T3 and enhances ubiquitin-dependent TRβ1 turnover; a common response of NRs to activating ligands. More surprisingly, SIRT1 knockdown only strongly inhibits T3 response of a subset of TRβ1 target genes, including glucose 6 phosphatase (G-6-Pc), and this is associated with blockade of TRβ1 binding to the G-6-Pc promoter. Drugs that target the SIRT1 pathway, resveratrol and nicotinamide, modulate T3 response at dual TRβ1/SIRT1 target genes. We propose that SIRT1 is a gene-specific TRβ1 co-regulator and TRβ1/SIRT1 interactions could play important roles in regulation of liver metabolic response. Our results open possibilities for modulation of subsets of TR target genes with drugs that influence the SIRT1 pathway.

The attenuation of sedimentation and convection in microgravity can sometimes decrease irregularities formed during macromolecular crystal growth. Current terrestrial protein crystal growth (PCG) capabilities are very different than those used during the Shuttle era and that are currently on the International Space Station (ISS). The focus of this experiment was to demonstrate the use of a commercial off-the-shelf, high throughput, PCG method in microgravity. Using Protein BioSolutions' microfluidic Plug Maker™/CrystalCard™ system, we tested the ability to grow crystals of the regulator of glucose metabolism and adipogenesis: peroxisome proliferator-activated receptor gamma (apo-hPPAR-γ LBD), as well as several PCG standards. Overall, we sent 25 CrystalCards™ to the ISS, containing ~10,000 individual microgravity PCG experiments in a 3U NanoRacks NanoLab (1U = 10(3) cm.). After 70 days on the ISS, our samples were returned with 16 of 25 (64%) microgravity cards having crystals, compared to 12 of 25 (48%) of the ground controls. Encouragingly, there were more apo-hPPAR-γ LBD crystals in the microgravity PCG cards than the 1g controls. These positive results hope to introduce the use of the PCG standard of low sample volume and large experimental density to the microgravity environment and provide new opportunities for macromolecular samples that may crystallize poorly in standard laboratories.

There are two homologous thyroid hormone (TH) receptors (TRs α and β), which are members of the nuclear hormone receptor (NR) family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3) in two cell backgrounds (HepG2 and HeLa). We find that hundreds of genes respond to T(3) or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3) response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3), TR regulation patterns and T(3) dose response. Cycloheximide (CHX) treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs).

This study explored whether discussion as a teaching strategy in mathematics classrooms could have positive gains in improving learners’ problem-solving performance, as well as their ability to make sense of real wor(l)d problems. This article discusses the partial findings of a bigger study that used a pre-test intervention or post-test mixed-method design and utilised both quantitative and qualitative data. Analysis of the data generated from both pre-tests and post-tests suggests that the intervention strategy significantly improved the experimental group’s problem-solving skills and sense-making performance. The statistical results illustrate that the experimental group performed significantly better than the comparison group in the post-test. The main finding of this study is that in classrooms of experimental schools in which discussion technique was successfully implemented, there was a statistically significant improvement in the learners’ competence in solving word problems.

The peroxisome proliferator-activated receptors (PPARs) regulate genes involved in lipid and carbohydrate metabolism, and are targets of drugs approved for human use. Whereas the crystallographic structure of the complex of full length PPARγ and RXRα is known, structural alterations induced by heterodimer formation and DNA contacts are not well understood. Herein, we report a small-angle X-ray scattering analysis of the oligomeric state of hPPARγ alone and in the presence of retinoid X receptor (RXR). The results reveal that, in contrast with other studied nuclear receptors, which predominantly form dimers in solution, hPPARγ remains in the monomeric form by itself but forms heterodimers with hRXRα. The low-resolution models of hPPARγ/RXRα complexes predict significant changes in opening angle between heterodimerization partners (LBD) and extended and asymmetric shape of the dimer (LBD-DBD) as compared with X-ray structure of the full-length receptor bound to DNA. These differences between our SAXS models and the high-resolution crystallographic structure might suggest that there are different conformations of functional heterodimer complex in solution. Accordingly, hydrogen/deuterium exchange experiments reveal that the heterodimer binding to DNA promotes more compact and less solvent-accessible conformation of the receptor complex.

Peroxisome proliferator activated receptors (PPARs δ, α and γ) are closely related transcription factors that exert distinct effects on fatty acid and glucose metabolism, cardiac disease, inflammatory response and other processes. Several groups developed PPAR subtype specific modulators to trigger desirable effects of particular PPARs without harmful side effects associated with activation of other subtypes. Presently, however, many compounds that bind to one of the PPARs cross-react with others and rational strategies to obtain highly selective PPAR modulators are far from clear. GW0742 is a synthetic ligand that binds PPARδ more than 300-fold more tightly than PPARα or PPARγ but the structural basis of PPARδ:GW0742 interactions and reasons for strong selectivity are not clear. Here we report the crystal structure of the PPARδ:GW0742 complex. Comparisons of the PPARδ:GW0742 complex with published structures of PPARs in complex with α and γ selective agonists and pan agonists suggests that two residues (Val312 and Ile328) in the buried hormone binding pocket play special roles in PPARδ selective binding and experimental and computational analysis of effects of mutations in these residues confirms this and suggests that bulky substituents that line the PPARα and γ ligand binding pockets as structural barriers for GW0742 binding. This analysis suggests general strategies for selective PPARδ ligand design.

Thiazolidinediones (TZDs) act through peroxisome proliferator activated receptor (PPAR) γ to increase insulin sensitivity in type 2 diabetes (T2DM), but deleterious effects of these ligands mean that selective modulators with improved clinical profiles are needed. We obtained a crystal structure of PPARγ ligand binding domain (LBD) and found that the ligand binding pocket (LBP) is occupied by bacterial medium chain fatty acids (MCFAs). We verified that MCFAs (C8-C10) bind the PPARγ LBD in vitro and showed that they are low-potency partial agonists that display assay-specific actions relative to TZDs; they act as very weak partial agonists in transfections with PPARγ LBD, stronger partial agonists with full length PPARγ and exhibit full blockade of PPARγ phosphorylation by cyclin-dependent kinase 5 (cdk5), linked to reversal of adipose tissue insulin resistance. MCFAs that bind PPARγ also antagonize TZD-dependent adipogenesis in vitro. X-ray structure B-factor analysis and molecular dynamics (MD) simulations suggest that MCFAs weakly stabilize C-terminal activation helix (H) 12 relative to TZDs and this effect is highly dependent on chain length. By contrast, MCFAs preferentially stabilize the H2-H3/β-sheet region and the helix (H) 11-H12 loop relative to TZDs and we propose that MCFA assay-specific actions are linked to their unique binding mode and suggest that it may be possible to identify selective PPARγ modulators with useful clinical profiles among natural products.

In this study an abstract food web and ecological case study data were used to determine high school pupils' and university students' ability to predict possible outcomes of interactions between populations within a community. Present data indicate that the majority of respondents could predict interactive outcomes within a food web if they were simple enough to be answered using strategies based on the food chain concept, but most respondents were unable to predict probable outcomes when the effects of a change in one population within a community are spread along multiple routes. Almost all the pupils and students could reorganise population data into satisfactory tables and graphs, but less than 50% of the respondents could integrate clues and predict outcomes acceptably. Data provided by three respondent age groups suggest that if clear conceptual development regarding interactions between populations does not take place at school level, misconceptions are likely to persist among first year university students. Also, the poor quality of answers given by respondents indicates that explicit teaching, prior to the use of such exercises, may greatly enhance their value. It is suggested that, by asking pupils to forecast events from supplied data, one is making explicit one of the implicit, applied reasons for studying ecological processes, i.e., conservation and management.