21 research outputs found

    Updating known distribution models for forecasting climate change impact on endangered species

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    To plan endangered species conservation and to design adequate management programmes, it is necessary to predict their distributional response to climate change, especially under the current situation of rapid change. However, these predictions are customarily done by relating de novo the distribution of the species with climatic conditions with no regard of previously available knowledge about the factors affecting the species distribution. We propose to take advantage of known species distribution models, but proceeding to update them with the variables yielded by climatic models before projecting them to the future. To exemplify our proposal, the availability of suitable habitat across Spain for the endangered Bonelli’s Eagle (Aquila fasciata) was modelled by updating a pre-existing model based on current climate and topography to a combination of different general circulation models and Special Report on Emissions Scenarios. Our results suggested that the main threat for this endangered species would not be climate change, since all forecasting models show that its distribution will be maintained and increased in mainland Spain for all the XXI century. We remark on the importance of linking conservation biology with distribution modelling by updating existing models, frequently available for endangered species, considering all the known factors conditioning the species’ distribution, instead of building new models that are based on climate change variables only.Ministerio de Ciencia e Innovación and FEDER (project CGL2009-11316/BOS

    Coherent ultrafast lattice-directed reaction dynamics of triiodide anion photodissociation

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    Solid-state reactions are influenced by the spatial arrangement of the reactants and the electrostatic environment of the lattice, which may enable lattice-directed chemical dynamics. Unlike the caging imposed by an inert matrix, an active lattice participates in the reaction, however, little evidence of such lattice participation has been gathered on ultrafast timescales due to the irreversibility of solid-state chemical systems. Here, by lowering the temperature to 80 K, we have been able to study the dissociative photochemistry of the triiodide anion (I<sub>3</sub>−) in single-crystal tetra-n-butylammonium triiodide using broadband transient absorption spectroscopy. We identified the coherently formed tetraiodide radical anion (I<sub>4</sub>•−) as a reaction intermediate. Its delayed appearance after that of the primary photoproduct, diiodide radical I<sub>2</sub>•−, indicates that I<sub>4</sub>•− was formed via a secondary reaction between a dissociated iodine radical (I<sup>•</sup>) and an adjacent I<sub>3</sub>−. This chemistry occurs as a result of the intermolecular interaction determined by the crystalline arrangement and is in stark contrast with previous solution studies

    BATLAS: Deconvoluting Brown Adipose Tissue

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    Recruitment and activation of thermogenic adipocytes have received increasing attention as a strategy to improve systemic metabolic control. The analysis of brown and brite adipocytes is complicated by the complexity of adipose tissue biopsies. Here, we provide an in-depth analysis of pure brown, brite, and white adipocyte transcriptomes. By combining mouse and human transcriptome data, we identify a gene signature that can classify brown and white adipocytes in mice and men. Using a machine-learning-based cell deconvolution approach, we develop an algorithm proficient in calculating the brown adipocyte content in complex human and mouse biopsies. Applying this algorithm, we can show in a human weight loss study that brown adipose tissue (BAT) content is associated with energy expenditure and the propensity to lose weight. This online available tool can be used for in-depth characterization of complex adipose tissue samples and may support the development of therapeutic strategies to increase energy expenditure in humans

    Suppression of Cancer Growth by Nonviral Gene Therapy Based on a Novel Reactive Oxygen Species-responsive Promoter

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    Increased reactive oxygen species (ROS) production has been reported as a distinctive feature of different pathologies including cancer. Therefore, we assessed whether increased ROS production in the cancer microenvironment could be selectively exploited to develop a selective anticancer therapy. For this purpose, we constructed a novel chimeric promoter, based on a ROS-response motif located in the VEGF gene promoter placed, in turn, downstream of a second ROS-response motif obtained from the early growth response 1 (Egr-1) gene promoter. The activity of the chimeric promoter was largely dependent on variations in intracellular ROS levels and showed a high inducible response to exogenous H2O2. Transient expression of the thymidine kinase (TK) gene driven by the chimeric promoter, followed by gancyclovir (GCV) administration, inhibited human colorectal cancer and melanoma cell growth in vitro and in vivo. Moreover, electrotransfer of the TK gene followed by GCV administration exerted a potent therapeutic effect on established tumors. This response was improved when combined with chemotherapeutic drugs. Thus, we show for the first time that a distinctive pro-oxidant state can be used to develop new selective gene therapeutics for cancer

    SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

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    Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population
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