739 research outputs found

    Fruit scent and observer colour vision shape food-selection strategies in wild capuchin monkeys

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    The senses play critical roles in helping animals evaluate foods, including fruits that can change both in colour and scent during ripening to attract frugivores. Although numerous studies have assessed the impact of colour on fruit selection, comparatively little is known about fruit scent and how olfactory and visual data are integrated during foraging. We combine 25 months of behavioural data on 75 wild, white-faced capuchins (Cebus imitator) with measurements of fruit colours and scents from 18 dietary plant species. We show that frequency of fruit-directed olfactory behaviour is positively correlated with increases in the volume of fruit odours produced during ripening. Monkeys with red-green colour blindness sniffed fruits more often, indicating that increased reliance on olfaction is a behavioural strategy that mitigates decreased capacity to detect red-green colour contrast. These results demonstrate a complex interaction among fruit traits, sensory capacities and foraging strategies, which help explain variation in primate behaviour.https://www.nature.com/articles/s41467-019-10250-9Published versio

    MEPicides: Potent antimalarial prodrugs targeting isoprenoid biosynthesis

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    AbstractThe emergence of Plasmodium falciparum resistant to frontline therapeutics has prompted efforts to identify and validate agents with novel mechanisms of action. MEPicides represent a new class of antimalarials that inhibit enzymes of the methylerythritol phosphate (MEP) pathway of isoprenoid biosynthesis, including the clinically validated target, deoxyxylulose phosphate reductoisomerase (Dxr). Here we describe RCB-185, a lipophilic prodrug with nanomolar activity against asexual parasites. Growth of P. falciparum treated with RCB-185 was rescued by isoprenoid precursor supplementation, and treatment substantially reduced metabolite levels downstream of the Dxr enzyme. In addition, parasites that produced higher levels of the Dxr substrate were resistant to RCB-185. Notably, environmental isolates resistant to current therapies remained sensitive to RCB-185, the compound effectively treated sexually-committed parasites, and was both safe and efficacious in malaria-infected mice. Collectively, our data demonstrate that RCB-185 potently and selectively inhibits Dxr in P. falciparum, and represents a promising lead compound for further drug development.</jats:p

    Activity budget and gut microbiota stability and flexibility across reproductive states in wild capuchin monkeys in a seasonal tropical dry forest

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    Abstract Background Energy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions. Results Reproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways. Conclusions Previous data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction

    “We Live on an Island:” Perspectives on Rural Family Caregiving for Adults with Alzheimer’s Disease and Related Dementias in the United States

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    As the United States’ aging population grows, there will be increased prevalence of individuals living with Alzheimer’s Disease and related dementias (ADRD), who largely rely on the support of their family caregivers. Family caregivers residing in rural areas face additional challenges with managing caregiving responsibilities and navigating support services. The purpose of this multilevel phenomenological qualitative study was to explore the assets, unique needs, and resources of rural-residing ADRD caregivers from the caregiver, provider, and policy influencers’ perspectives. The study took place between 2019 through 2021 in northern Arizona, a largely rural and geographically vast area home to caregivers from diverse backgrounds. Twenty-seven caregivers to a loved one with ADRD participated in focus groups. Twelve health and social services providers and twelve policy influencers, those involved in leadership positions for aging programs or advocacy groups, completed individual interviews. Caregivers demonstrate many assets which contribute to their ability to manage and cope with their caregiving role. However, caregivers face a series of issues related to their caregiving role and need early and ongoing education regarding ADRD. There is a lack of resources available in rural areas, in particular providers, making it challenging to obtain needed resources necessary to support their loved one with ADRD. Furthermore, there is a need for more providers trained in working with aging adults and those experiencing ADRD, and a need for more culturally relevant resources

    Synthetic Lethal Targeting of ARID1A-Mutant Ovarian Clear Cell Tumors with Dasatinib

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    New targeted approaches to ovarian clear cell carcinomas (OCCC) are needed, given the limited treatment options in this disease and the poor response to standard chemotherapy. Using a series of high-throughput cell-based drug screens in OCCC tumor cell models, we have identified a synthetic lethal (SL) interaction between the kinase inhibitor dasatinib and a key driver in OCCC, ARID1A mutation. Imposing ARID1A deficiency upon a variety of human or mouse cells induced dasatinib sensitivity, both in vitro and in vivo, suggesting that this is a robust synthetic lethal interaction. The sensitivity of ARID1A-deficient cells to dasatinib was associated with G1 -S cell-cycle arrest and was dependent upon both p21 and Rb. Using focused siRNA screens and kinase profiling, we showed that ARID1A-mutant OCCC tumor cells are addicted to the dasatinib target YES1. This suggests that dasatinib merits investigation for the treatment of patients with ARID1Amutant OCCC. Mol Cancer Ther; 15(7); 1472-84. Ó2016 AACR.</p

    The success of the Montreal Protocol in mitigating interactive effects of stratospheric ozone depletion and climate change on the environment

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    The Montreal Protocol and its Amendments have been highly effective in protecting the stratospheric ozone layer, preventing global increases in solar ultraviolet-B radiation (UV-B; 280-315 nm) at Earth's surface, and reducing global warming. While ongoing and projected changes in UV-B radiation and climate still pose a threat to human health, food security, air and water quality, terrestrial and aquatic ecosystems, and construction materials and fabrics, the Montreal Protocol continues to play a critical role in protecting Earth's inhabitants and ecosystems by addressing many of the United Nations Sustainable Development Goals.Non peer reviewe

    Effects of interventions on depression and anxiety in older people with physical health problems in the criminal justice system : a systematic review

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    The demand for health care in older people involved in the criminal justice system is high. The prevalence of mental and physical health conditions for people living in prison is greater than in community populations. After systematically searching 21 databases, we found no targeted interventions to support depression or anxiety for this group of people. 24 studies (including interventions of yoga, creative-arts-based programmes, positive psychology, or mindfulness-based interventions and psychotherapy) did contain people older than 50 years, but this only represented a minority (10%) of the overall study population. No single study reported outcomes of physical health. Future interventions need to consider the needs and views of this vulnerable group. Specific gendered and coproduced interventions are required to enhance the implementation, feasibility, and acceptability of interventions that are delivered in prisons

    Testing the cognitive-behavioural maintenance models across DSM-5 bulimic-type eating disorder diagnostic groups: A multi-centre study

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    The original cognitive-behavioural (CB) model of bulimia nervosa, which provided the basis for the widely used CB therapy, proposed that specific dysfunctional cognitions and behaviours maintain the disorder. However, amongst treatment completers, only 40–50 % have a full and lasting response. The enhanced CB model (CB-E), upon which the enhanced version of the CB treatment was based, extended the original approach by including four additional maintenance factors. This study evaluated and compared both CB models in a large clinical treatment seeking sample (N = 679), applying both DSM-IV and DSM-5 criteria for bulimic-type eating disorders. Application of the DSM-5 criteria reduced the number of cases of DSM-IV bulimic-type eating disorders not otherwise specified to 29.6 %. Structural equation modelling analysis indicated that (a) although both models provided a good fit to the data, the CB-E model accounted for a greater proportion of variance in eating-disordered behaviours than the original one, (b) interpersonal problems, clinical perfectionism and low self-esteem were indirectly associated with dietary restraint through over-evaluation of shape and weight, (c) interpersonal problems and mood intolerance were directly linked to binge eating, whereas restraint only indirectly affected binge eating through mood intolerance, suggesting that factors other than restraint may play a more critical role in the maintenance of binge eating. In terms of strength of the associations, differences across DSM-5 bulimic-type eating disorder diagnostic groups were not observed. The results are discussed with reference to theory and research, including neurobiological findings and recent hypotheses

    Early Mississippian evaporites of coastal tropical wetlands

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    Extensive evaporites in Lower Mississippian successions from palaeoequatorial regions are commonly used as evidence for an arid to semi‐arid palaeoclimate. However, in this article, detailed studies of evaporites and their context refute this interpretation. Detailed sedimentological and petrographical analysis of the Lower Mississippian of northern Britain, is combined with archived log data from more than 40 boreholes across southern Scotland, northern England and Northern Ireland, and published literature from Canada. Two key cores from the Tweed Basin and the northern margin of the Northumberland – Solway Basin contain 178 evaporite intervals and reveal twelve distinct forms of gypsum and anhydrite across seven facies that are associated with planar laminated siltstone and intercalated thin beds of ferroan dolostone. Nodular gypsum and anhydrite, typically in intervals <1 to 2 m thick, are integral components of the succession. Nodular evaporite occurs within about 1 m of a palaeosurface, but most evaporite deposits represent ephemeral brine pans to semi‐permanent hypersaline lakes or salinas on a floodplain that was subjected periodically to storm surges introducing marine waters. Formation of evaporites under a strongly seasonal climate in a coastal wetland is supported by palaeosol types and geochemical proxies, and from palaeobotanical evidence published previously. Although 65% of modern equatorial areas experience a strongly seasonal climatic regime, salinas and sabkhas are a minor component today in comparison with the evidence from these Lower Mississippian successions. This implies that the earliest terrestrial environments were complex and dynamic, providing a diverse range of habitats in which the early tetrapods became terrestrialized and represent a setting that is rarely preserved in the geological record
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