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1.
Conserv Biol ; : e14372, 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39268844

ABSTRACT

Communities have a strong role in protecting biodiversity. In addition to participation in restoration, a range of actions in the public or private sphere may support biodiversity. Despite this, there is a lack of clarity about what actions should be prioritized for behavior change campaigns. We developed and applied a method to prioritize community actions for biodiversity conservation that incorporates an expert-based assessment of impact and a community-informed measure of the likelihood of uptake. In stage 1, experts (n = 143) completed a survey that quantified the relative impact of actions based on best-worst scaling of perceived impact. In stage 2, surveyed community members (n = 3200) ranked the likelihood of adopting actions based on the ease or difficulty of performing each action, and the opportunity for change based on the proportion of respondents not yet engaging in each behavior. Experts gave the following actions the highest ranking for impact: voting for the environment (first), participating in restoration in ecological priority areas (second), and purchasing and protecting remnant bushland (third). When considering the disciplinary background and institutional background of experts, voting and participating in restoration activities remained in the upper ranked options. However, there was some divergence between these groups. For example, reducing beef consumption was ranked third by university-based experts but ranked 28th by experts based in state government. Overall, community members ranked the following behaviors as most likely to be adopted: following quarantine laws (first), reducing plastic use (second), and managing pets (third). Top likelihood ranking of actions was minimally affected by community characteristics (nature relatedness, gender, location). Integrating these findings, the action ranked most favorably for impact, likelihood, and opportunity was participating in restoration. Choosing actions for behavior change campaigns requires consideration of the entire social-ecological system-from social factors that enable or constrain adoption to the ecological impact of actions across relevant social and ecological contexts.


Inducción de perspectivas diversas para priorizar las acciones comunitarias a favor de la conservación de la biodiversidad Las comunidades juegan un papel importante en la protección de la biodiversidad. Además de participar en la restauración, existe una gama de acciones públicas y privadas que pueden ayudar a la biodiversidad. A pesar de esto, no está claro cuáles acciones deben priorizarse en las campañas de cambio conductual. Desarrollamos y aplicamos un método para priorizar las acciones comunitarias a favor de la conservación de la biodiversidad que incorpora la evaluación por experto del impacto y la medida comunitaria de la probabilidad de captación. En la fase 1, los expertos (n = 143) completaron una encuesta que cuantificó el impacto relativo de las acciones con base en una escala mejor­peor del impacto percibido. En la fase 2, los miembros de la comunidad (n = 3200) clasificaron la probabilidad del éxito de las acciones con base en la proporción de respondientes que todavía no participan en cada comportamiento. Los expertos otorgaron la clasificación más alta para el impacto a las siguientes acciones: votar por el ambiente (primero), participar en la restauración de áreas ecológicas prioritarias (segundo) y adquirir y proteger matorrales remanentes (tercero). Cuando consideramos la formación disciplinaria e institucional de los expertos, la votación y la participación en las actividades de restauración permanecieron en las opciones con clasificación más alta; sin embargo, existió una divergencia entre estos grupos. Por ejemplo, los expertos de las universidades clasificaron en tercero la reducción del consumo de carne de res, pero los expertos del gobierno estatal lo clasificaron en vigésimo octavo. En general, los miembros de la comunidad clasificaron los siguientes comportamientos como los más probables de ser adoptados: seguir las normas de cuarentena (primero), reducir el uso de plásticos (segundo) y el manejo de mascotas (tercero). Las características comunitarias (relación con la naturaleza, género, ubicación) afectaron en lo mínimo a la clasificación más alta de probabilidad de las acciones. Al integrar estos resultados, la acción mejor clasificada en cuanto a impacto, probabilidad y oportunidad fue la participación en la restauración. La selección de acciones para las campañas de cambio conductual requiere que se considere todo el sistema socio ecológico ­ desde los factores sociales que permiten o restringen la conservación hasta las acciones de impacto ecológico relevantes en los contextos sociales y ecológicos.

2.
Hepatol Commun ; 7(10)2023 10 01.
Article in English | MEDLINE | ID: mdl-37695073

ABSTRACT

BACKGROUND: Bile, which contains bile acids, the natural ligands for farnesoid x receptor (FXR), moves from the liver to the intestine through bile ducts. Ductular reaction often occurs during biliary obstruction. A subset of patients with erythropoietic protoporphyria, an inherited genetic mutation in heme biosynthetic enzyme ferrochelatase, accumulate porphyrin-containing bile plugs, leading to cholestasis. Here, we examined the link between FXR, bile plug formation, and how heme biosynthesis relates to this connection. METHODS: We treated female and male wild-type and global and tissue-specific Fxr knockout mice with a diet containing 3,5-diethoxycarbonyl-1,4-dihydrocollidine, an inhibitor of ferrochelatase, and examined the expression of heme biosynthetic genes. We mined FXR mouse ChIP-Seq data, performed biochemical and histological analysis, and tested HepG2 and primary human hepatocytes after treatment with obeticholic acid, an FXR agonist. RESULTS: We observed that hepatic but not intestinal Fxr loss resulted in reduced bile plugs and ductular reaction in the liver. Then, we examined if FXR plays a regulatory role in heme biosynthesis and found significantly lower porphyrin accumulation in 3,5-diethoxycarbonyl-1, 4-dihydrocollidine-fed Fxr knockout mice. Gene expression and FXR mouse ChIP-Seq atlas analysis revealed that FXR orchestrates the expression of multiple heme biosynthetic enzymes. Finally, human HepG2 cells and primary human hepatocytes treated with obeticholic acid, showed increased expression of several heme biosynthetic genes. CONCLUSIONS: Overall, our data show that hepatic Fxr is necessary to maintain ductular reaction and accumulation of bile plugs. FXR can direct the expression of multiple heme biosynthetic genes. Thus, modulating FXR activity in EPP patients may help alleviate its associated liver disease.


Subject(s)
Cholestasis , Porphyrins , Animals , Female , Humans , Male , Mice , Ferrochelatase , Heme , Liver
3.
J Environ Manage ; 342: 118128, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37210815

ABSTRACT

Diverse solutions are needed to reduce human impacts on nature. Fostering individual stewardship behaviours that protect, restore, and encourage sustainable use of nature will need to be part of this mix of solutions. A key challenge then is how to increase the uptake of such behaviours. Social capital provides a framework to explore the diverse types of social influences on nature stewardship. We surveyed a representative sample of residents of New South Wales, Australia (n = 3220) to explore how facets of social capital influenced individual willingness to adopt diverse types of stewardship behaviours. Analysis confirmed that parts of social capital differentially influence distinct types of stewardship behaviours including lifestyle, social, on-ground, and citizenship behaviours. All behaviours were positively influenced by perceptions of shared values within social network, and past participation in environmental groups. Yet some components of social capital exhibited mixed associations with each type of stewardship behaviour. For example, collective agency was associated with greater willingness to engage in social, on-ground, and citizenship behaviours, whereas institutional trust was negatively associated with willingness to engage in lifestyle, on-ground and citizenship behaviours. These findings show that social context provides an important foundation for building stewardship engagement.


Subject(s)
Social Capital , Humans , Australia , Social Environment , Trust , Surveys and Questionnaires
4.
Trends Ecol Evol ; 38(7): 643-653, 2023 07.
Article in English | MEDLINE | ID: mdl-36898928

ABSTRACT

Ecosystem restoration conventionally focuses on ecological targets. However, while ecological targets are crucial to mobilizing political, social, and financial capital, they do not encapsulate the need to: integrate social, economic, and ecological dimensions and systems approaches; reconcile global targets and local objectives; and measure the rate of progress toward multiple and synergistic goals. Restoration is better conceived as an inclusive social-ecological process that integrates diverse values, practices, knowledge, and restoration objectives across temporal and spatial scales and stakeholder groups. Taking a more process-based approach will ultimately enable greater social-ecological transformation, greater restoration effectiveness, and more long-lasting benefits to people and nature across time and place.


Subject(s)
Conservation of Natural Resources , Ecosystem , Humans , Conservation of Natural Resources/methods , Ecology
5.
Australas Emerg Care ; 26(3): 230-238, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36710228

ABSTRACT

BACKGROUND: Rates of self-harm and suicide are increasing world-wide, particularly in young females. Emergency departments (EDs) are a common first point-of-contact for young people who self-harm. We examined age- and sex-related differences in: (1) rates of self-harm over an eight-year period; (2) changes in demographic, presentation, and treatment characteristics over this period, and; (3) rates of, and time to, self-harm re-presentation. METHODS: This was a retrospective observational study of all self-harm presentations in persons aged nine years and older to the Royal Melbourne Hospital ED over an eight-year period, 1 January 2012-31 December 2019. The Royal Melbourne Hospital is one of the largest and busiest public EDs in Melbourne, Australia and serves a primary catchment area of approximately 1.5 million people. RESULTS: There were 551,692 presentations to the Royal Melbourne Hospital ED over this period (57.6 % by females). Of these, 7736 (1.4 %) were self-harm related. These self-harm presentations involved 5428 individuals (54.8 % female), giving an overall repetition event-rate of 11.2 %. Self-harm related presentations increased by 5 % per year (Incidence Rate Ratio [IRR 1.05, 95 % CI 1.02-1.08); a 44 % increase over the eight-year period (IRR 1.44, 95 % CI 1.15-1.80). This increase was more pronounced for young people aged< 25 years. The most common method was self-poisoning, primarily by anxiolytics or analgesics. The proportion of presentations involving self-poisoning alone declined modestly over time, whilst the proportion involving self-injury alone increased. For just over half of all presentations the person was seen by ED mental health staff. The median time to first re-presentation was 4.5 months (Inter-Quartile Range [IQR] 0.7-13.2 months). CONCLUSIONS: Rates of hospital presenting self-harm may be increasing, particularly amongst young people, whilst most self-harm presentations occurred outside office hours; so appropriate ED staffing, training and clinical care models are needed. Around half of those with a repeat episode of self-harm repeated within three months of their index (i.e., first recorded) presentation. Efforts to establish appropriate aftercare services, including alternatives to ED services with service availability 24 h a day 7 days a week, aimed at reducing repetition rates, should be prioritised.


Subject(s)
Self-Injurious Behavior , Suicide , Humans , Female , Adolescent , Male , Victoria/epidemiology , Self-Injurious Behavior/epidemiology , Self-Injurious Behavior/psychology , Suicide/psychology , Hospitals , Emergency Service, Hospital
6.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210088, 2023 01 02.
Article in English | MEDLINE | ID: mdl-36373914

ABSTRACT

Forest restoration has been proposed as a scalable nature-based solution to achieve global environmental and socio-economic outcomes and is central to many policy initiatives, such as the Bonn Challenge. Restored forests contain appreciable biodiversity, improve habitat connectivity and sequester carbon. Incentive mechanisms (e.g. payments for ecosystem services and allocation of management rights) have been a focus of forest restoration efforts for decades. Yet, there is still little understanding of their role in promoting restoration success. We conducted a systematic literature review to investigate how incentive mechanisms are used to promote forest restoration, outcomes, and the biophysical and socio-economic factors that influence implementation and program success. We found that socio-economic factors, such as governance, monitoring systems and the experience and beliefs of participants, dominate whether or not an incentive mechanism is successful. We found that approximately half of the studies report both positive ecological and socio-economic outcomes. However, reported adverse outcomes were more commonly socio-economic than ecological. Our results reveal that achieving forest restoration at a sufficient scale to meet international commitments will require stronger assessment and management of socio-economic factors that enable or constrain the success of incentive mechanisms. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Subject(s)
Ecosystem , Motivation , Humans , Forests , Biodiversity , Conservation of Natural Resources
7.
Conserv Biol ; 37(2): e14009, 2023 04.
Article in English | MEDLINE | ID: mdl-36285591

ABSTRACT

The loss and degradation of nature can lead to hopelessness and despair, which may undermine engagement in conservation actions. Emerging movements, such as that behind the organization Conservation Optimism, aim to avert potential despair of those involved in conservation. Some argue that fostering positive states, such as hope or optimism, can motivate engagement and action; however, others question whether fostering hope or optimism may inadvertently undermine perceived gravity of conservation challenges. We examined this issue by quantifying dispositional hope and optimism with a representative sample of Australians (n = 4285) and assessing their relationship with indicators of conservation engagement. We used the Great Barrier Reef (GBR) in Australia as a case study. We asked participants what they could do to help the GBR, then classified their responses into 2 outcome variables: identifying climate actions (i.e., actions that tackle the main threat to the reef) and identifying plastic actions (i.e., actions that are popular among community members). We also quantified likelihood of performing these actions and appraisals of both threats and actions. One dimension of hope, hope pathways (defined by Snyder's hope theory as knowing different ways to act), was associated with greater capacity to identify climate-related behaviors (odds ratio [OR] = 1.44) and plastic reduction behaviors (OR = 1.22) and greater likelihood of adopting climate-related actions (ß = 0.20). Optimism was associated with recognition of plastic reduction behaviors only (OR = 1.22). Neither hope nor optimism undermined appraisal of conservation threats. The effects of optimism were mediated by reduced action futility, and effects of hope pathways were mediated by stronger perceptions of threats to the reef (threat appraisal) and confidence in performing useful actions (coping appraisal). Our findings suggest that dispositional hope can strengthen, rather than undermine, appraisal of conservation challenges and solutions and thereby increase conservation engagement.


La pérdida y la degradación de la naturaleza pueden derivar en desesperanza y desesperación, las cuales pueden disminuir la participación en las actividades de conservación. Los movimientos, como aquél detrás de la organización Conservation Optimism, buscan evitar la potencial desesperación de aquellos involucrados en la conservación. Hay quienes argumentan que promover estados positivos, como la esperanza y el optimismo, puede debilitar inadvertidamente la gravedad percibida de los retos para la conservación. Analizamos este tema mediante la cuantificación de la disposición a la esperanza y el optimismo en una muestra representativa de australianos (n = 4285) y la valoración de sus relaciones con los indicadores de participación en la conservación. Usamos la Gran Barrera de Arrecife como un estudio de caso. Preguntamos a los participantes qué podrían hacer para ayudar a este ecosistema y después clasificamos sus respuestas en dos variables de resultado: identificar acciones climáticas (acciones que combaten la amenaza principal del arrecife) e identificar acciones plásticas (acciones que son populares entre los miembros de la comunidad). También cuantificamos la probabilidad de realizar estas acciones y las valoraciones tanto de las amenazas como de las acciones. Una dimensión de la esperanza, los caminos de la esperanza (definidas por la Teoría de la Esperanza de Snyder como saber actuar de diferentes maneras), estuvo asociada con una mayor capacidad para identificar los comportamientos relacionados con el clima (razón de oportunidades [OR]=1.44) y aquellos de reducción del plástico (OR = 1.22) y también con una mayor probabilidad de actuar en relación con el clima (ß = 0.20). El optimismo solamente estuvo asociado con el reconocimiento de los comportamientos de reducción del plástico (OR = 1.22). Ni el optimismo ni la esperanza debilitaron la valoración de las amenazas a la conservación. Los efectos del optimismo estuvieron mediados por la reducción de la futilidad de las acciones, mientras que los efectos de los caminos de la esperanza lo estuvieron por percepciones más firmes de las amenazas para el arrecife (valoración de amenazas) y la confianza en realizar acciones útiles (valoración del afrontamiento). Nuestros resultados sugieren que la disposición a la esperanza puede fortalecer, en lugar de debilitar, la valoración de la conservación y, por lo tanto, incrementar su participación.


Subject(s)
Conservation of Natural Resources , Humans , Australia , Probability
8.
Mar Pollut Bull ; 172: 112793, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34385021

ABSTRACT

Governments in Australia and internationally are experimenting with policy instruments to facilitate the adoption of farming practices with reduced environmental impacts. The Great Barrier Reef (Australia) is one such case, where sustained efforts over 20 years have yielded insufficient progress towards targets to reduce the impacts of agriculture on water quality in downstream marine ecosystems. We present a critical review of policy instruments as implemented in Great Barrier Reef catchments. We catalogue the evolving mix of policy instruments employed in reef programs, and examine evidence of the effectiveness of agricultural extension, financial incentives, and direct regulation of farming practices. There is little robust evidence to assess instrument effectiveness, in part due to the evolving mix of the instruments employed, weak program evaluation and heterogeneity of agricultural enterprises. We identify the need to improve the understanding of instrument fit to landholders and enterprises. We recommend a modelling approach to clarify pathways to impact and guide improved policy evaluation.


Subject(s)
Ecosystem , Water Quality , Agriculture , Farms , Policy
9.
Biochim Biophys Acta Mol Basis Dis ; 1867(11): 166211, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34273530

ABSTRACT

Sex differences in physiology are noted in clinical and animal studies. However, mechanisms underlying these observed differences between males and females remain elusive. Nuclear receptors control a wide range of physiological pathways and are expressed in the gastrointestinal tract, including the mouth, stomach, liver and intestine. We investigated the literature pertaining to ER, AR, FXR, and PPAR regulation and highlight the sex differences in nutrient metabolism along the digestive system. We chose these nuclear receptors based on their metabolic functions, and hormonal actions. Intriguingly, we noted an overlap in target genes of ER and FXR that modulate mucosal integrity and GLP-1 secretion, whereas overlap in target genes of PPARα with ER and AR modulate lipid metabolism. Sex differences were seen not only in the basal expression of nuclear receptors, but also in activation as their endogenous ligand concentrations fluctuate depending on nutrient availability. Finally, in this review, we speculate that interactions between the nuclear receptors may influence overall metabolic decisions in the gastrointestinal tract in a sex-specific manner.


Subject(s)
Digestion/physiology , Gastrointestinal Diseases/epidemiology , Gastrointestinal Tract/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Female , Gastrointestinal Diseases/etiology , Gastrointestinal Diseases/physiopathology , Health Status Disparities , Humans , Incidence , Male , Sex Factors , Signal Transduction/physiology
10.
Environ Manage ; 68(2): 184-197, 2021 08.
Article in English | MEDLINE | ID: mdl-34125266

ABSTRACT

Peri-urban areas, defined as the region between urban and rural settlements, are heterogeneous, dynamic regions experiencing rapid land use change in cities around the world. Ongoing development and land use change has resulted in the fragmentation, degradation and loss of natural assets, threatening biodiversity, and ecosystems within the peri-urban region. With much of this land privately owned, the actions of landholders have considerable opportunity to deliver environmental outcomes, yet an understanding of this diverse group of landholders is challenging. Through a survey of landholders (N = 184) in Australian peri-urban regions we sought to understand motivations and barriers to engagement in environmental management. Factors influencing willingness to engage in environmental management included perceived personal capacity to act, feeling that actions were helpful, and community participation. We discuss how engagement strategies could incorporate these findings by focussing on improving capacity and environmental knowledge with hands on, face-to-face extension activities, encouraging simple actions, and fostering greater community interaction.


Subject(s)
Conservation of Natural Resources , Ecosystem , Australia , Biodiversity , Cities
11.
Int J Biol Sci ; 17(5): 1203-1216, 2021.
Article in English | MEDLINE | ID: mdl-33867840

ABSTRACT

Manganese superoxide dismutase (MnSOD) acetylation (Ac) has been shown to be a key post-translational modification important in the regulation of detoxification activity in various disease models. We have previously demonstrated that MnSOD lysine-68 (K68) acetylation (K68-Ac) leads to a change in function from a superoxide-scavenging homotetramer to a peroxidase-directed monomer. Here, we found that estrogen receptor positive (ER+) breast cancer cell lines (MCF7 and T47D), selected for continuous growth in cisplatin (CDDP) and doxorubicin (DXR), exhibited an increase in MnSOD-K68-Ac. In addition, MnSOD-K68-Ac, as modeled by the expression of a validated acetylation mimic mutant gene (MnSODK68Q ), also led to therapy resistance to CDDP and DXR, altered mitochondrial structure and morphology, and aberrant cellular metabolism. MnSODK68Q expression in mouse embryo fibroblasts (MEFs) induced an in vitro transformation permissive phenotype. Computerized molecular protein dynamics analysis of both MnSOD-K68-Ac and MnSOD-K68Q exhibited a significant change in charge distribution along the α1 and α2 helices, directly adjacent to the Mn2+ binding site, implying that this decrease in surface charge destabilizes tetrameric MnSOD, leading to an enrichment of the monomer. Finally, monomeric MnSOD, as modeled by amber codon substitution to generate MnSOD-K68-Ac or MnSOD-K68Q expression in mammalian cells, appeared to incorporate Fe to maximally induce its peroxidase activity. In summary, these findings may explain the mechanism behind the observed structural and functional change of MnSOD-K68-Ac.


Subject(s)
Breast Neoplasms , Carcinogenesis , Cisplatin/pharmacology , Doxorubicin/pharmacology , Mitochondria , Sirtuins/metabolism , Superoxide Dismutase/metabolism , Acetylation , Animals , Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Carcinogenesis/drug effects , Carcinogenesis/metabolism , Cell Line, Tumor , Drug Resistance, Neoplasm , Free Radical Scavengers/metabolism , Humans , Inactivation, Metabolic , MCF-7 Cells , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Protein Processing, Post-Translational
12.
Ambio ; 50(7): 1364-1377, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33496942

ABSTRACT

Understanding how private landholders make deforestation decisions is of paramount importance for conservation. Behavioural frameworks from the social sciences have a lot to offer researchers and practitioners, yet these insights remain underutilised in describing what drives landholders' deforestation intentions under important political, social, and management contexts. Using survey data of private landholders in Queensland, Australia, we compare the ability of two popular behavioural models to predict future deforestation intentions, and propose a more integrated behavioural model of deforestation intentions. We found that the integrated model outperformed other models, revealing the importance of threat perceptions, attitudes, and social norms for predicting landholders' deforestation intentions. Social capital, policy uncertainty, and years of experience are important contextual moderators of these psychological factors. We conclude with recommendations for promoting behaviour change in this deforestation hotspot and highlight how others can adopt similar approaches to illuminate more proximate drivers of environmental behaviours in other contexts.


Subject(s)
Conservation of Natural Resources , Intention , Attitude , Australia , Queensland
14.
Environ Manage ; 66(3): 289-304, 2020 09.
Article in English | MEDLINE | ID: mdl-32588074

ABSTRACT

Voluntary private land conservation (PLC) is becoming an increasingly important complement to state protected areas around the world. PLC programs can serve as valuable strategies to increase biodiversity on agricultural lands, but their effectiveness depends on high participation rates. Amidst growing concerns regarding scalability and effectiveness of conservation strategies like national parks, researchers and practitioners are looking for new strategies to increase adoption of PLC. This study investigates the demographic, social, and psychological factors associated with participation in three classes of voluntary PLC programs-grant payments, land management agreements, and covenants-and how this relates to landholders' attitudes toward tree clearing. We compare participation rates between these programs in Queensland and identify the most frequently cited reasons why land managers have or have not participated. Land managers who are more involved in agricultural organizations and whose tree clearing decisions are more influenced by the aesthetic value of trees are more likely to have participated in one or more of these programs. Participation was highly biased toward once-off grant payments, and participation in covenants was lowest of all programs. Although 58% of land managers have never participated, nearly half expressed interest in one or more programs. A lack of program knowledge and perceived losses of autonomy were the most frequently cited barriers to participation. We conclude with recommendations for increasing participation rates and raise important questions that need to be answered in order to promote a PLC culture that effectively curbs ongoing habitat degradation.


Subject(s)
Social Capital , Trees , Australia , Conservation of Natural Resources , Ecosystem , Perception , Queensland
15.
Am J Physiol Gastrointest Liver Physiol ; 318(4): G682-G693, 2020 04 01.
Article in English | MEDLINE | ID: mdl-32003602

ABSTRACT

Postprandial dyslipidemia is a common feature of insulin-resistant states and contributes to increased cardiovascular disease risk. Recently, bile acids have been recognized beyond their emulsification properties as important signaling molecules that promote energy expenditure, improve insulin sensitivity, and lower fasting lipemia. Although bile acid receptors have become novel pharmaceutical targets, their effects on postprandial lipid metabolism remain unclear. Here, we investigated the potential role of bile acids in regulation of postprandial chylomicron production and triglyceride excursion. Healthy C57BL/6 mice were given an intraduodenal infusion of taurocholic acid (TA) under fat-loaded conditions, and circulating lipids were measured. Targeting of bile acid receptors was achieved with GW4064, a synthetic agonist to the farnesoid X receptor (FXR), and deoxycholic acid (DCA), an activator of the Takeda G-protein-coupled receptor 5. TA, GW4064, and DCA treatments all lowered postprandial lipemia. FXR agonism also reduced intestinal triglyceride content and activity of microsomal triglyceride transfer protein, involved in chylomicron assembly. Importantly, TA (but not DCA) effects were largely lost in FXR knockout mice. These bile acid effects are reminiscent of the antidiabetic hormone glucagon-like peptide-1 (GLP-1). Although the GLP-1 receptor agonist exendin-4 retained its ability to acutely lower postprandial lipemia during bile acid sequestration and FXR deficiency, it did raise hepatic expression of the rate-limiting enzyme for bile acid synthesis. Bile acid signaling may be an important mechanism of controlling dietary lipid absorption, and bile acid receptors may constitute novel targets for the treatment of postprandial dyslipidemia.NEW & NOTEWORTHY We present new data suggesting potentially important roles for bile acids in regulation of postprandial lipid metabolism. Specific bile acid species, particularly secondary bile acids, were found to markedly inhibit absorption of dietary lipid and reduce postprandial triglyceride excursion. These effects appear to be mediated via bile acid receptors, farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5). Importantly, bile acid signaling may trigger glucagon-like peptide-1 (GLP-1) secretion, which may in turn mediate the marked inhibitory effects on dietary fat absorption.


Subject(s)
Deoxycholic Acid/pharmacology , Hyperlipidemias/drug therapy , Isoxazoles/pharmacology , Lipid Metabolism/drug effects , Postprandial Period , Receptors, Cytoplasmic and Nuclear/agonists , Animals , Bile Acids and Salts/metabolism , Bile Acids and Salts/pharmacology , Cholesterol 7-alpha-Hydroxylase/genetics , Cholesterol 7-alpha-Hydroxylase/metabolism , Exenatide/pharmacology , Gastric Emptying/drug effects , Gene Expression Regulation/drug effects , Insulin/blood , Intestinal Mucosa , Intestines , Male , Mice , Mice, Inbred C57BL , Receptors, G-Protein-Coupled/agonists , Taurocholic Acid/pharmacology
16.
J Environ Manage ; 254: 109777, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31733476

ABSTRACT

Psychosocial factors determine individual and collective behaviours, and there is growing evidence of their influence on land management behaviours. Native vegetation management encompasses biophysical, economic, political, and cultural dimensions that are immensely complex, and a more thorough understanding of the personal and cultural dimensions of deforestation activity is required. We emphasise this interdisciplinary imperative using Queensland, Australia, as an exemplar case study, where the controversial Vegetation Management Act1999 has been met with significant scrutiny over its effects on private landholders and its ability to curb deforestation behaviours. We surveyed landholders across Queensland in order to identify different landholder typologies based upon (1) their recent tree clearing behaviours and (2) their psychosocial characteristics, mapped their distribution in the landscape, and determined the unique demographic and psychosocial factors associated with typology membership. We identified a heterogeneous mosaic of landholders in the clearing landscape, composed of four clearing typologies and five psychosocial typologies. Social norms, identity, trust, and security played crucial roles in distinguishing different types of landholders. The two most contrasting clearing typologies-active and inactive clearers-were primarily located in hot- and cold-spots of deforestation, respectively; in contrast, most psychosocial typologies could be found throughout the landscape, highlighting the potential benefit of complementing generalised state-wide psychosocial targets with localised behavioural targets. We discuss how conservation policy instruments can be regionally tailored, and relevant strategies for effective communication and engagement can be developed to create behaviour change by understanding the characteristics and distribution of these types of landholders. If modified top-down efforts (e.g. strategic messages, community-based communication) can be supplemented with more bottom-up approaches (e.g. collective learning, building network support), sustainable land management in deforestation hotspots around the world may be achievable.


Subject(s)
Conservation of Natural Resources , Social Change , Australia , Queensland , Surveys and Questionnaires
17.
Conserv Biol ; 34(1): 93-102, 2020 02.
Article in English | MEDLINE | ID: mdl-31152562

ABSTRACT

Attitudes have been a commonly used psychological measure of program effectiveness in conservation social science research. The major limitation of this approach is that attitudes do not always translate into behavior and therefore may not provide an accurate assessment of program success. Given that achieving conservation goals generally relies on understanding and changing human behavior, we argue for the need to assess behavior rather than attitudes as an indicator of conservation outcomes. Psychological theory shows that attitudes and behavior are distinct, but related, concepts. Measuring conservation behaviors involves identifying the target behavior or behaviors and the optimal time to measure and then selecting the most appropriate method of measurement (i.e., direct observation, objective indicators, self-reported behavior, and behavioral intentions) that considers the strengths and weaknesses of each approach. We call for conservation programs to focus on influencing behavior rather than attitudes alone and encourage conservation practitioners and researchers to collect high-quality behavioral data to more effectively inform policy and programs.


Logro del Impacto de la Conservación Cambiando el Enfoque en las Actitudes Humanas a los Comportamientos Resumen Las actitudes han sido utilizadas comúnmente como una medida psicológica de la eficacia de una investigación de ciencias sociales de la conservación. La principal limitación de este enfoque es que las actitudes no siempre se traducen en comportamiento y, por lo tanto, pueden no proporcionar una evaluación precisa del éxito del programa. Dado que el logro de los objetivos de conservación generalmente se basa en la comprensión y el cambio del comportamiento humano, argumentamos la necesidad de evaluar el comportamiento en lugar de las actitudes como un indicador de los resultados de conservación. La teoría psicológica muestra que las actitudes y el comportamiento son conceptos distintos, pero relacionados. La medida de comportamientos de conservación implica la identificación del comportamiento o los comportamientos buscados y del tiempo óptimo para medirlos y luego seleccionar el método de medición más apropiado (i. e., observación directa, indicadores objetivos, comportamiento auto reportado e intenciones de comportamiento) que considere las fortaleza y debilidades de cada enfoque. Hacemos un llamado para que los programas de conservación se centren en influir en el comportamiento en lugar de las actitudes por sí solas y alentamos a que los profesionales e investigadores de la conservación recopilen datos conductuales de calidad para que las políticas y programas tengan información eficaz.


Subject(s)
Attitude , Conservation of Natural Resources , Humans
18.
Nat Commun ; 10(1): 2399, 2019 06 03.
Article in English | MEDLINE | ID: mdl-31160585

ABSTRACT

Manganese superoxide dismutase (MnSOD) functions as a tumor suppressor; however, once tumorigenesis occurs, clinical data suggest MnSOD levels correlate with more aggressive human tumors, implying a potential dual function of MnSOD in the regulation of metabolism. Here we show, using in vitro transformation and xenograft growth assays that the MnSOD-K68 acetylation (Ac) mimic mutant (MnSODK68Q) functions as a tumor promoter. Interestingly, in various breast cancer and primary cell types the expression of MnSODK68Q is accompanied with a change of MnSOD's stoichiometry from a known homotetramer complex to a monomeric form. Biochemical experiments using the MnSOD-K68Q Ac-mimic, or physically K68-Ac (MnSOD-K68-Ac), suggest that these monomers function as a peroxidase, distinct from the established MnSOD superoxide dismutase activity. MnSODK68Q expressing cells exhibit resistance to tamoxifen (Tam) and cells selected for Tam resistance exhibited increased K68-Ac and monomeric MnSOD. These results suggest a MnSOD-K68-Ac metabolic pathway for Tam resistance, carcinogenesis and tumor progression.


Subject(s)
Breast Neoplasms/genetics , Carcinogenesis/genetics , Drug Resistance, Neoplasm/genetics , Superoxide Dismutase/genetics , Acetylation , Animals , Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Line, Tumor , Disease Progression , Humans , In Vitro Techniques , Lysine/metabolism , MCF-7 Cells , Mice , Mutation , Neoplasm Transplantation , Peroxidase/metabolism , Protein Structure, Quaternary/genetics , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism , Tamoxifen/therapeutic use , Tumor Suppressor Proteins
19.
J Cogn Neurosci ; 31(7): 1044-1053, 2019 07.
Article in English | MEDLINE | ID: mdl-30883291

ABSTRACT

Recent behavioral modeling and pupillometry studies suggest that neuromodulatory arousal systems play a role in regulating decision formation but neurophysiological support for these observations is lacking. We employed a randomized, double-blinded, placebo-controlled, crossover design to probe the impact of pharmacological enhancement of catecholamine levels on perceptual decision-making. Catecholamine levels were manipulated using the clinically relevant drugs methylphenidate and atomoxetine, and their effects were compared with those of citalopram and placebo. Participants performed a classic EEG oddball paradigm that elicits the P3b, a centro-parietal potential that has been shown to trace evidence accumulation, under each of the four drug conditions. We found that methylphenidate and atomoxetine administration shortened RTs to the oddball targets. The neural basis of this behavioral effect was an earlier P3b peak latency, driven specifically by an increase in its buildup rate without any change in its time of onset or peak amplitude. This study provides neurophysiological evidence for the catecholaminergic enhancement of a discrete aspect of human decision-making, that is, evidence accumulation. Our results also support theoretical accounts suggesting that catecholamines may enhance cognition via increases in neural gain.


Subject(s)
Brain/physiology , Catecholamines/physiology , Decision Making/physiology , Visual Perception/physiology , Adolescent , Adrenergic Uptake Inhibitors/administration & dosage , Adult , Atomoxetine Hydrochloride/administration & dosage , Brain/drug effects , Citalopram/administration & dosage , Cross-Over Studies , Decision Making/drug effects , Dopamine Uptake Inhibitors/administration & dosage , Double-Blind Method , Electroencephalography , Evoked Potentials, Visual/drug effects , Humans , Male , Methylphenidate/administration & dosage , Middle Aged , Selective Serotonin Reuptake Inhibitors/administration & dosage , Visual Perception/drug effects , Young Adult
20.
Sci Rep ; 8(1): 16501, 2018 11 07.
Article in English | MEDLINE | ID: mdl-30405152

ABSTRACT

Mice lacking Sirt2 spontaneously develop tumors in multiple organs, as well as when expressed in combination with oncogenic KrasG12D, leading to pancreatic tumors. Here, we report that after caerulein-induced pancreatitis, Sirt2-deficient mice exhibited an increased inflammatory phenotype and delayed pancreatic tissue recovery. Seven days post injury, the pancreas of Sirt2-/- mice display active inflammation, whereas wild-type mice had mostly recovered. In addition, the pancreas from the Sirt2-/- mice exhibited extensive tissue fibrosis, which was still present at six weeks after exposure. The mice lacking Sirt2 also demonstrated an enhanced whole body pro-inflammatory phenotype that was most obvious with increasing age. Importantly, an accumulation of a cell population with spontaneous cancerous KrasG12D mutations was observed in the Sirt2-/- mice that is enhanced in the recovering pancreas after exposure to caerulein. Finally, transcriptome analysis of the pancreas of the Sirt2-/- mice exhibited a pro-inflammatory genomic signature. These results suggest that loss of Sirt2, as well as increased age, enhanced the immune response to pancreatic injury and induced an inflammatory phenotype permissive for the accumulation of cells carrying oncogenic Kras mutations.


Subject(s)
Ceruletide/adverse effects , Mutation , Pancreatitis/etiology , Pancreatitis/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Sirtuin 2/genetics , Animals , Disease Models, Animal , Disease Susceptibility/immunology , Female , Genetic Predisposition to Disease , Immunohistochemistry , Male , Mice , Mice, Knockout , Pancreatitis/pathology , Regeneration
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