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1.
BMJ Open ; 14(1): e069430, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286691

RESUMO

INTRODUCTION: Fever treatment is commonly applied in patients with sepsis but its impact on survival remains undetermined. Patients with respiratory and haemodynamic failure are at the highest risk for not tolerating the metabolic cost of fever. However, fever can help to control infection. Treating fever with paracetamol has been shown to be less effective than cooling. In the SEPSISCOOL pilot study, active fever control by external cooling improved organ failure recovery and early survival. The main objective of this confirmatory trial is to assess whether fever control at normothermia can improve the evolution of organ failure and mortality at day 60 of febrile patients with septic shock. This study will compare two strategies within the first 48 hours of septic shock: treatment of fever with cooling or no treatment of fever. METHODS AND ANALYSIS: SEPSISCOOL II is a pragmatic, investigator-initiated, adaptive, multicentre, open-label, randomised controlled, superiority trial in patients admitted to the intensive care unit with febrile septic shock. After stratification based on the acute respiratory distress syndrome status, patients will be randomised between two arms: (1) cooling and (2) no cooling. The primary endpoint is mortality at day 60 after randomisation. The secondary endpoints include the evolution of organ failure, early mortality and tolerance. The target sample size is 820 patients. ETHICS AND DISSEMINATION: The study is funded by the French health ministry and was approved by the ethics committee CPP Nord Ouest II (Amiens, France). The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04494074.


Assuntos
Sepse , Choque Séptico , Humanos , Choque Séptico/terapia , Choque Séptico/complicações , Respiração Artificial , Projetos Piloto , Febre/terapia , Febre/complicações , Sepse/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
2.
Conserv Biol ; 38(2): e14202, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37811723

RESUMO

Conservation references have long been used in conservation biology to compare current biodiversity processes and states with past conditions. However, beyond the paucity of data for the construction of ancient, even prehuman, references, the relevance of these ancient references for studying ecosystems radically modified by human activities is questionable, particularly when the notions of conservation references and conservation objectives are confused and when several conservation ethics coexist that require distinct references. Because of this implicit heterogeneity in the nature of the references and their temporal baseline, conservation references not only have different meanings, but also deliver different messages. I propose establishing a common framework for conservation references to approach past biological systems and build comparable references between studies and projects. The selection of these references (distinct from conservation objectives) should be an early, explicit, standardized, and transparent milestone in any conservation process and these references should be based on state, pressure, or process dynamics, rather than fixed states. Finally, the importance of the diversity of temporal baselines used to build conservation references and to measure anthropogenic impacts should be recognized to understand the biodiversity crisis in its entirety.


Creación de referentes para la conservación de la naturaleza Resumen Los referentes en conservación se han usado durante mucho tiempo en la biología de la conservación para comparar los procesos y estados actuales de la biodiversidad con las condiciones del pasado. Sin embargo, más allá de la escasez de datos para la construcción de referentes antiguos, o incluso prehumanos, es cuestionable la relevancia de estos referentes antiguos para estudiar los ecosistemas con modificaciones radicales por actividades humanas, particularmente cuando se confunden las nociones de los referentes en conservación y los objetivos de conservación y cuando coexisten varios enfoques éticos de la conservación que requieren de diferentes referentes. Debido a esta heterogeneidad implícita en la naturaleza de los referentes y su línea base temporal, los referentes en conservación no sólo tienen diferentes significados, sino también comunican diferentes mensajes. Propongo que se establezca un marco común para que los referentes en conservación puedan abordar los sistemas biológicos del pasado y crear referentes comparables entre estudios y proyectos. La selección de estos referentes (distintos a los objetivos de conservación) debería ser un hito temprano, explícito, estandarizado y transparente en cualquier proceso de conservación y estos referentes deberían basarse en las dinámicas del estado, presión o proceso en lugar de los estados fijos. Por último, se debería reconocer la importancia de la diversidad de líneas base temporales que se usa para crear referentes en la conservación y para medir el impacto antropogénico para así entender la crisis de la biodiversidad en su totalidad.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Biodiversidade , Atividades Humanas
3.
Evol Appl ; 16(3): 609-624, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36969142

RESUMO

Current oncogenic theories state that tumors arise from cell lineages that sequentially accumulate (epi)mutations, progressively turning healthy cells into carcinogenic ones. While those models found some empirical support, they are little predictive of intraspecies age-specific cancer incidence and of interspecies cancer prevalence. Notably, in humans and lab rodents, a deceleration (and sometimes decline) of cancer incidence rate has been found at old ages. Additionally, dominant theoretical models of oncogenesis predict that cancer risk should increase in large and/or long-lived species, which is not supported by empirical data. Here, we explore the hypothesis that cellular senescence could explain those incongruent empirical patterns. More precisely, we hypothesize that there is a trade-off between dying of cancer and of (other) ageing-related causes. This trade-off between organismal mortality components would be mediated, at the cellular scale, by the accumulation of senescent cells. In this framework, damaged cells can either undergo apoptosis or enter senescence. Apoptotic cells lead to compensatory proliferation, associated with an excess risk of cancer, whereas senescent cell accumulation leads to ageing-related mortality. To test our framework, we build a deterministic model that first describes how cells get damaged, undergo apoptosis, or enter senescence. We then translate those cellular dynamics into a compound organismal survival metric also integrating life-history traits. We address four different questions linked to our framework: can cellular senescence be adaptive, do the predictions of our model reflect epidemiological patterns observed among mammal species, what is the effect of species sizes on those answers, and what happens when senescent cells are removed? Importantly, we find that cellular senescence can optimize lifetime reproductive success. Moreover, we find that life-history traits play an important role in shaping the cellular trade-offs. Overall, we demonstrate that integrating cellular biology knowledge with eco-evolutionary principles is crucial to solve parts of the cancer puzzle.

4.
Pathogens ; 12(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36986327

RESUMO

BACKGROUND: Polymicrobial infections are complex infections associated with worse outcomes compared to monomicrobial infections. We need simple, fast, and cost-effective animal models to assess their still poorly known pathogenesis. METHODS: We developed a Drosophila melanogaster polymicrobial infection model for opportunistic pathogens and assessed its capacity to discriminate the effects of bacterial mixtures taken from cases of human polymicrobial infections by Aeromonas strains. A systemic infection was obtained by needle pricking the dorsal thorax of the flies, and the fly survival was monitored over time. Different lineages of the flies were infected by a single strain or paired strains (strain ratio 1:1). RESULTS: Individual strains killed more than 80% of the flies in 20 h. The course of infection could be altered with a microbial mix. The model could distinguish between the diverse effects (synergistic, antagonistic, and no difference) that resulted in a milder, more severe, or similar infection, depending on the paired strain considered. We then investigated the determinants of the effects. The effects were maintained in deficient fly lineages for the main signaling pathways (Toll deficient and IMD deficient), which suggests an active microbe/microbe/host interaction. CONCLUSION: These results indicate that the D. melanogaster systemic infection model is consistent with the study of polymicrobial infection.

5.
JAMA Intern Med ; 183(6): 520-531, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36946232

RESUMO

Importance: Given the high risk of thrombosis and anticoagulation-related bleeding in patients with hypoxemic COVID-19 pneumonia, identifying the lowest effective dose of anticoagulation therapy for these patients is imperative. Objectives: To determine whether therapeutic anticoagulation (TA) or high-dose prophylactic anticoagulation (HD-PA) decreases mortality and/or disease duration compared with standard-dose prophylactic anticoagulation (SD-PA), and whether TA outperforms HD-PA; and to compare the net clinical outcomes among the 3 strategies. Design, Settings, and Participants: The ANTICOVID randomized clinical open-label trial included patients with hypoxemic COVID-19 pneumonia requiring supplemental oxygen and having no initial thrombosis on chest computer tomography with pulmonary angiogram at 23 health centers in France from April 14 to December 13, 2021. Of 339 patients randomized, 334 were included in the primary analysis-114 patients in the SD-PA group, 110 in the HD-PA, and 110 in the TA. At randomization, 90% of the patients were in the intensive care unit. Data analyses were performed from April 13, 2022, to January 3, 2023. Interventions: Patients were randomly assigned (1:1:1) to receive either SD-PA, HD-PA, or TA with low-molecular-weight or unfractionated heparin for 14 days. Main Outcomes and Measures: A hierarchical criterion of all-cause mortality followed by time to clinical improvement at day 28. Main secondary outcome was net clinical outcome at day 28 (composite of thrombosis, major bleeding, and all-cause death). Results: Among the study population of 334 individuals (mean [SD] age, 58.3 [13.0] years; 226 [67.7%] men and 108 [32.3%] women), use of HD-PA and SD-PA had similar probabilities of favorable outcome (47.3% [95% CI, 39.9% to 54.8%] vs 52.7% [95% CI, 45.2% to 60.1%]; P = .48), as did TA compared with SD-PA (50.9% [95% CI, 43.4% to 58.3%] vs 49.1% [95% CI, 41.7% to 56.6%]; P = .82) and TA compared with HD-PA (53.5% [95% CI 45.8% to 60.9%] vs 46.5% [95% CI, 39.1% to 54.2%]; P = .37). Net clinical outcome was met in 29.8% of patients receiving SD-PA (20.2% thrombosis, 2.6% bleeding, 14.0% death), 16.4% receiving HD-PA (5.5% thrombosis, 3.6% bleeding, 11.8% death), and 20.0% receiving TA (5.5% thrombosis, 3.6% bleeding, 12.7% death). Moreover, HD-PA and TA use significantly reduced thrombosis compared with SD-PA (absolute difference, -14.7 [95% CI -6.2 to -23.2] and -14.7 [95% CI -6.2 to -23.2], respectively). Use of HD-PA significantly reduced net clinical outcome compared with SD-PA (absolute difference, -13.5; 95% CI -2.6 to -24.3). Conclusions and Relevance: This randomized clinical trial found that compared with SD-PA, neither HD-PA nor TA use improved the primary hierarchical outcome of all-cause mortality or time to clinical improvement in patients with hypoxemic COVID-19 pneumonia; however, HD-PA resulted in significantly better net clinical outcome by decreasing the risk of de novo thrombosis. Trial Registration: ClinicalTrials.gov Identifier: NCT04808882.


Assuntos
COVID-19 , Trombose , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , COVID-19/complicações , Heparina/administração & dosagem , Hemorragia/induzido quimicamente , Trombose/tratamento farmacológico , Trombose/prevenção & controle , Trombose/induzido quimicamente , Anticoagulantes/efeitos adversos
6.
Sci Total Environ ; 838(Pt 2): 156195, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35623521

RESUMO

Human-wildlife conflicts are associated with a threat to large carnivores, as well as with economic and social costs, thus challenging conservation management around the world. In this study, we explored the effectiveness of common management interventions used worldwide for the purpose of conflict reduction using an evidence-based framework combining expert assessment of intervention effectiveness, impact and uncertainty of assessment. We first conducted a literature review of human-large carnivore conflicts across the world. Based on this review, we identified three main types of management interventions (non-lethal, translocations, and lethal management) and we assessed their effectiveness. Our review indicates that, although the characteristics of conflicts with large carnivores are heavily influenced by the local context and the species, the main issues are depredation on livestock, space-sharing, and attacks on humans. Non-lethal interventions are more likely to reduce conflict, whereas translocations and lethal interventions are mostly ineffective and/or harmful to carnivore populations, without fostering successful long-term coexistence. The literature on conflict management is often imprecise and lacks consistency between studies or situations, which generally makes comparisons difficult. Our protocol allows for the reliable comparison of experiments characterized by heterogeneous standards, response variables, protocols, and quality of evidence. Nevertheless, we encourage the use of systematic protocols with common good standards in order to provide more reliable empirical evidence. This would clarify the relative effectiveness of conflict management strategies and contribute to the global reduction in the occurrence of human-large carnivore conflicts across the world.


Assuntos
Carnívoros , Conservação dos Recursos Naturais , Animais , Animais Selvagens , Conservação dos Recursos Naturais/métodos , Humanos , Gado , Comportamento Predatório
7.
BMJ Open ; 12(4): e059383, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473740

RESUMO

INTRODUCTION: COVID-19 induces venous, arterial and microvascular thrombosis, involving several pathophysiological processes. In patients with severe COVID-19 without macrovascular thrombosis, escalating into high-dose prophylactic anticoagulation (HD-PA) or therapeutic anticoagulation (TA) could be beneficial in limiting the extension of microvascular thrombosis and forestalling the evolution of lung and multiorgan microcirculatory dysfunction. In the absence of data from randomised trials, clinical practice varies widely. METHODS AND ANALYSIS: This is a French multicentre, parallel-group, open-label, randomised controlled superiority trial to compare the efficacy and safety of three anticoagulation strategies in patients with COVID-19. Patients with oxygen-treated COVID-19 showing no pulmonary artery thrombosis on computed tomography with pulmonary angiogram will be randomised to receive either low-dose PA, HD-PA or TA for 14 days. Patients attaining the extremes of weight and those with severe renal failure will not be included. We will recruit 353 patients. Patients will be randomised on a 1:1:1 basis, and stratified by centre, use of invasive mechanical ventilation, D-dimer levels and body mass index. The primary endpoint is a hierarchical criterion at day 28 including all-cause mortality, followed by the time to clinical improvement defined as the time from randomisation to an improvement of at least two points on the ordinal clinical scale. Secondary outcomes include thrombotic and major bleeding events at day 28, individual components of the primary endpoint, number of oxygen-free, ventilator-free and vasopressor-free days at day 28, D-dimer and sepsis-induced coagulopathy score at day 7, intensive care unit and hospital stay at day 28 and day 90, and all-cause death and quality of life at day 90. ETHICS AND DISSEMINATION: The study has been approved by an ethical committee (Ethics Committee, Ile de France VII, Paris, France; reference 2020-A03531-38). Patients will be included after obtaining their signed informed consent. The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04808882.


Assuntos
COVID-19 , Anticoagulantes/uso terapêutico , Coagulação Sanguínea , Humanos , Microcirculação , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Sci Rep ; 12(1): 4081, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260728

RESUMO

Reintroduction, the human-mediated movement of organisms to re-establish locally extinct populations, has become a popular conservation tool. However, because reintroductions often focus on local or national conservation issues, their contribution to the conservation of biodiversity at large scale remains unclear. While taxonomic biases have already been identified in reintroduction programs at regional scales, studies have stressed the need to account for other facets of biodiversity when assessing the relevance of the allocation of conservation efforts. In particular, it may be very fruitful to discriminate if and how such taxonomic biases may influence the functional complementarity of reintroduction targets, and to which extent reintroduction practitioners may have focused on species performing more singular functions than others. Here, we investigate the diversity of functional traits supported by reintroduced species of terrestrial birds and mammals in Europe. For each taxonomic group, we explored the functional representativeness of reintroduction targets at the European scale, i.e., whether species involved in reintroduction programs collectively represent the range of functional trait variation observed in the regional assemblage. Because additional conservation value could have been given by practitioners to species performing singular functions, we also measured the functional distinctiveness of reintroduced species. We found that reintroductions of birds did not focus on functionally distinct species, and that the subset of reintroduced birds is representative of the functional diversity at a continental scale. However, reintroductions of mammals involved more functionally distinct species than expected, even though reintroduced mammals are not collectively representative of the functional diversity of the continental assemblage.


Assuntos
Aves , Conservação dos Recursos Naturais , Animais , Biodiversidade , Europa (Continente) , Humanos , Mamíferos
10.
Mar Pollut Bull ; 171: 112695, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34271508

RESUMO

A traditional taxonomic approach coupled to a biological traits analysis was conducted in order to provide a new insight into macrobenthic communities associated with subtidal sandy environments. Results suggest that the macro-scale distribution of benthic communities is mainly driven by the migration rate of bedforms (sandbank, barchan dune and transversal dune) which changes the sediment grain size and reduces macrobenthic diversity. A classic scheme of species/traits succession was also observed from less to more physically disturbed areas. Finally, the high frequency of migration events homogenized macrobenthic communities between the troughs to the crest of bedforms. As bedforms areas are targeted for the commissioning of offshore windfarms the information provided by the present paper will be particularly useful to implement the environmental impact assessment required for such activities at sea.


Assuntos
Ecossistema , Areia , Biodiversidade , Meio Ambiente , Sedimentos Geológicos
11.
JAMA Netw Open ; 4(7): e2114328, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34313743

RESUMO

Importance: Current guidelines recommend brain magnetic resonance imaging (MRI) for clinical management of patients with severe herpes simplex encephalitis (HSE). However, the prognostic value of brain imaging has not been demonstrated in this setting. Objective: To investigate the association between early brain MRI data and functional outcomes of patients with HSE at 90 days after intensive care unit (ICU) admission. Design, Setting, and Participants: This multicenter cohort study was conducted in 34 ICUs in France from 2007 to 2019 and recruited all patients who received a clinical diagnosis of encephalitis and exhibited cerebrospinal fluid positivity for herpes simplex virus DNA in the polymerase chain reaction analysis. Data analysis was performed from January to April 2020. Exposures: All patients underwent a standard brain MRI during the first 30 days after ICU admission. Main Outcomes and Measures: MRI acquisitions were analyzed by radiologists blinded to patients' outcomes, using a predefined score. Multivariable logistic regression and supervised hierarchical classifiers methods were used to identify factors associated with poor outcome at 90 days, defined by a score of 3 to 6 (indicating moderate-to-severe disability or death) on the Modified Rankin Scale. Results: Overall, 138 patients (median [interquartile range {IQR}] age, 62.6 [54.0-72.0] years; 75 men [54.3%]) with an admission median (IQR) Glasgow Coma Scale score of 9 (6-12) were studied. The median (IQR) delay between ICU admission and MRI was 1 (1-7) days. At 90 days, 95 patients (68.8%) had a poor outcome, including 16 deaths (11.6%). The presence of fluid-attenuated inversion recovery MRI signal abnormalities in more than 3 brain lobes (odds ratio [OR], 25.71; 95% CI, 1.21-554.42), age older than 60 years (OR, 7.62; 95% CI, 2.02-28.91), and the presence of diffusion-weighted MRI signal abnormalities in the left thalamus (OR, 6.90; 95% CI, 1.12-43.00) were independently associated with poor outcome. Machine learning models identified bilateral diffusion abnormalities as an additional factor associated with poor outcome (34 of 39 patients [87.2%] with bilateral abnormalities had poor outcomes) and confirmed the functional burden of left thalamic lesions, particularly in older patients (all 11 patients aged >60 years had left thalamic lesions). Conclusions and Relevance: These findings suggest that in adult patients with HSE requiring ICU admission, extensive MRI changes in the brain are independently associated with poor functional outcome at 90 days. Thalamic diffusion signal changes were frequently observed and were associated with poor prognosis, mainly in older patients.


Assuntos
Encefalite por Herpes Simples/complicações , Imageamento por Ressonância Magnética/estatística & dados numéricos , Desempenho Físico Funcional , Idoso , Estudos de Coortes , Encefalite por Herpes Simples/diagnóstico por imagem , Encefalite por Herpes Simples/epidemiologia , Feminino , França/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Razão de Chances
12.
Sci Rep ; 11(1): 7813, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837276

RESUMO

Although captive breeding programs are valuable for conservation, they have been shown to be associated with genetic changes, such as adaptation to captivity or inbreeding. In addition, reproductive performance is strongly age-dependent in most animal species. These mechanisms that potentially impact reproduction have often been studied separately, while their interactions have rarely been addressed. In this study, using a large dataset of nine male and female reproductive parameters measured for 12,295 captive houbara bustards (Chlamydotis undulata undulata) over 24 years, we investigated the relative and interactive effects of age, inbreeding and number of generations in captivity on reproduction. We clearly identified (1) senescence patterns in all parameters studied; (2) negative effects of inbreeding on sperm characteristics, display behavior, egg weight, egg volume and hatching probability; and (3) changes in phenotypic values for seven parameters according to number of generations in captivity. However, the effect sizes associated with age were substantially greater than those associated with inbreeding and number of generations in captivity. Beyond the independent effects of these three factors on reproductive parameters, the results highlighted their interactive effects and thus the importance of integrating them in the design of genetic management plans for conservation breeding programs.


Assuntos
Aves/genética , Endogamia , Linhagem , Reprodução/genética , Comportamento Sexual Animal/fisiologia , Fatores Etários , Animais , Conservação dos Recursos Naturais , Feminino , Masculino , Fenótipo , Espermatozoides
13.
Blood Adv ; 5(5): 1523-1534, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33683342

RESUMO

Dysregulated immune response is the key factor leading to unfavorable coronavirus disease 2019 (COVID-19) outcome. Depending on the pathogen-associated molecular pattern, the NLRP3 inflammasome can play a crucial role during innate immunity activation. To date, studies describing the NLRP3 response during severe acute respiratory syndrome coronavirus 2 infection in patients are lacking. We prospectively monitored caspase-1 activation levels in peripheral myeloid cells from healthy donors and patients with mild to critical COVID-19. The caspase-1 activation potential in response to NLRP3 inflammasome stimulation was opposed between nonclassical monocytes and CD66b+CD16dim granulocytes in severe and critical COVID-19 patients. Unexpectedly, the CD66b+CD16dim granulocytes had decreased nigericin-triggered caspase-1 activation potential associated with an increased percentage of NLRP3 inflammasome impaired immature neutrophils and a loss of eosinophils in the blood. In patients who recovered from COVID-19, nigericin-triggered caspase-1 activation potential in CD66b+CD16dim cells was restored and the proportion of immature neutrophils was similar to control. Here, we reveal that NLRP3 inflammasome activation potential differs among myeloid cells and could be used as a biomarker of a COVID-19 patient's evolution. This assay could be a useful tool to predict patient outcome. This trial was registered at www.clinicaltrials.gov as #NCT04385017.


Assuntos
COVID-19/sangue , Inflamassomos/metabolismo , Células Mieloides/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Biomarcadores/sangue , COVID-19/imunologia , Estudos de Casos e Controles , Humanos , Inflamassomos/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação
14.
Addict Biol ; 26(2): e12939, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32720424

RESUMO

Ethanol consumption impairs learning and memory through disturbances of NMDA-type glutamate receptor-dependent synaptic plasticity (long-term depression [LTD] and long-term potentiation [LTP]) in the hippocampus. Recently, we demonstrated that two ethanol binge-like episodes in young adult rats selectively blocked NMDA-LTD in hippocampal slices, increased NMDA receptor sensitivity to a GluN2B subunit antagonist, and induced cognitive deficits. Here, using knockout adult mice, we show that a stress-responsive transcription factor of the heat shock factor family, HSF2, which is involved in the perturbation of brain development induced by ethanol, participates in these processes. In the absence of ethanol, hsf2-/- mice show a selective loss of LTD in the hippocampus, which is associated with an increased sensitivity of NMDA-field excitatory postsynaptic potentials (fEPSPs) to a GluN2B antagonist, compared with wild-type (WT) mice. These results suggest that HSF2 is required for proper glutamatergic synaptic transmission and LTD plasticity. After 1 month of chronic ethanol consumption in a two-bottle choice paradigm, WT mice showed an increase in hippocampal synaptic transmission, an enhanced sensitivity to GluN2B antagonist, and a blockade of LTD. In contrast, such modulation of synaptic transmission and plasticity were absent in hsf2-/- mice. We conclude that HSF2 is an important mediator of both glutamatergic neurotransmission and synaptic plasticity in basal conditions and also mediates ethanol-induced neuroadaptations of the hippocampus network after chronic ethanol intake.


Assuntos
Etanol/farmacologia , Fatores de Transcrição de Choque Térmico/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , N-Metilaspartato/efeitos dos fármacos , Adolescente , Adulto , Fatores Etários , Animais , Hipocampo/efeitos dos fármacos , Humanos , Camundongos
15.
Zoo Biol ; 39(6): 422-435, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32956518

RESUMO

Protection and restoration of species in the wild may require conservation breeding programs under genetic management to minimize deleterious effects of genetic changes that occur in captivity, while preserving populations' genetic diversity and evolutionary resilience. Here, through interannual pedigree analyses, we first assessed the efficiency of a 21-year genetic management, including minimization of mean kinship, inbreeding avoidance, and regular addition of founders, of a conservation breeding program targeting on Houbara bustard (Chlamydotis undulata undulata) in Morocco. Secondly, we compared pedigree analyses, the classical way of assessing and managing genetic diversity in captivity, to molecular analyses based on seven microsatellites. Pedigree-based results indicated an efficient maintenance of the genetic diversity (99% of the initial genetic diversity retained) while molecular-based results indicated an increase in allelic richness and an increase in unbiased expected heterozygosity across time. The pedigree-based average inbreeding coefficient F remained low (between 0.0004 and 0.003 in 2017) while the proportion of highly inbred individuals (F > .1) decreased over time and reached 0.2% in 2017. Furthermore, pedigree-based F and molecular-based individual multilocus heterozygosity were weakly negatively correlated, (Pearson's r = -.061 when considering all genotyped individuals), suggesting that they cannot be considered as alternatives, but rather as complementary sources of information. These findings suggest that a strict genetic monitoring and management, based on both pedigree and molecular tools can help mitigate genetic changes and allow to preserve genetic diversity and evolutionary resilience in conservation breeding programs.


Assuntos
Aves/genética , Animais , Aves/classificação , Conservação dos Recursos Naturais , DNA/genética , Feminino , Genótipo , Endogamia , Masculino , Repetições de Microssatélites , Marrocos , Linhagem , Fatores de Tempo
16.
Sci Adv ; 5(5): eaau2642, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31131318

RESUMO

In France, illegal hunting of the endangered ortolan bunting Emberiza hortulana has been defended for the sake of tradition and gastronomy. Hunters argued that ortolan buntings trapped in southwest France originate from large and stable populations across the whole of Europe. Yet, the European Commission referred France to the Court of Justice of the European Union (EU) in December 2016 for infringements to legislation (IP/16/4213). To better assess the impact of hunting in France, we combined Pan-European data from archival light loggers, stable isotopes, and genetics to determine the migration strategy of the species across continents. Ortolan buntings migrating through France come from northern and western populations, which are small, fragmented and declining. Population viability modeling further revealed that harvesting in southwest France is far from sustainable and increases extinction risk. These results provide the sufficient scientific evidence for justifying the ban on ortolan harvesting in France.


Assuntos
Migração Animal , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Passeriformes/fisiologia , Animais , Teorema de Bayes , Análise por Conglomerados , Deutério , União Europeia , Feminino , França , Geografia , Atividades Humanas , Humanos , Isótopos , Masculino , Oriente Médio , Noruega , Dinâmica Populacional , Probabilidade , Estações do Ano
17.
Ecol Evol ; 9(8): 4421-4430, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31031916

RESUMO

Kinship and inbreeding are two major components involved in sexual selection and mating system evolution. However, the mechanisms underlying recognition and discrimination of genetically related or inbred individuals remain unclear. We investigated whether kinship and inbreeding information is related to low-frequency vocalizations, "booms," produced by males during their courtship in the lekking houbara bustard (Chlamydotis undulata undulata). Based on a captive breeding program where the pedigree of all males is known, we investigated the similarity of booms' acoustic parameters among captive males more or less individually inbred and therefore genetically related with each other. In the wild, we investigated the relationship between the spatial distribution of males within leks and the similarity of acoustic parameters of their booms. In the captive population, we found (a) a relationship between the individual inbreeding level of captive males and their vocalization parameters; (b) that kin share similar frequency and temporal characteristics of their vocalizations. In the wild, we found no evidence for spatial structuring of males based on their acoustic parameters, in agreement with previous genetic findings on the absence of kin association within houbara bustard leks. Overall, our results indicate that genetic information potentially related to both the identity and quality of males is contained in their vocalizations.

18.
Oecologia ; 188(3): 765-776, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30219947

RESUMO

Reproduction costs depend on the general life-history strategies employed by organisms for resource acquisition, the decision rules on resource allocation, and the resource availability. Although the predictability of resource availability is expected to influence the breeding strategy, the relationship between predictability and strategy has rarely been investigated at the population level. One reason is that, while the resource availability is commonly variable in space and time, their predictability is generally assumed constant. Here, we addressed the temporal variation of the breeding strategy and its associated survival cost in a hibernating population of Tamias sibiricus, in which food resources vary in their availability between years and in their predictability within years. Based on 11 years of mark-recapture data, we used multi-event modelling to investigate seasonal variations in reproduction costs of female chipmunks that breed twice a year (spring and summer). In summer, during which a large variety and quantity of resources is available (income breeding strategy), the proportion of breeding females was consistent across years and reproduction yielded no mortality cost. In contrast, in spring, the proportion of breeding females was positively correlated with the amount of resources available for hibernation (partial capital breeding strategy). Spring reproduction yielded no immediate cost, but induced a delayed mortality cost over the next winter if future unknown conditions were unfavorable. Our findings highlight complex temporal reproductive patterns in a short-lived species: not only does the modality of resource acquisition vary among seasons, but also the decision rule to breed and its associated cost.


Assuntos
Hibernação , Reprodução , Animais , Cruzamento , Feminino , Humanos , Sciuridae , Estações do Ano
19.
Proc Natl Acad Sci U S A ; 115(13): 3404-3409, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29531037

RESUMO

Reintroductions offer a powerful tool for reversing the effects of species extirpation and have been increasingly used over recent decades. However, this species-centered conservation approach has been criticized for its strong biases toward charismatic birds and mammals. Here, we investigated whether reintroduced species can be representative of the phylogenetic diversity within these two groups at a continental scale (i.e., Europe, North and Central America). Using null models, we found that reintroduced birds and mammals of the two subcontinents tend to be more evolutionarily distinct than expected by chance, despite strong taxonomic biases leading to low values of phylogenetic diversity. While evolutionary considerations are unlikely to have explicitly driven the allocation of reintroduction efforts, our results illustrate an interest of reintroduction practitioners toward species with fewer close relatives. We discuss how this phylogenetic framework allows us to investigate the contribution of reintroductions to the conservation of biodiversity at multiple geographic scales. We argue that because reintroductions rely on a parochial approach of conservation, it is important to first understand how the motivations and constraints at stake at a local context can induce phylogenetic biases before trying to assess the relevance of the allocation of reintroduction efforts at larger scales.


Assuntos
Biodiversidade , Evolução Biológica , Aves/fisiologia , Conservação dos Recursos Naturais , Mamíferos/fisiologia , Animais , América Central , Europa (Continente) , Filogenia
20.
Ann Intensive Care ; 7(1): 45, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28447330

RESUMO

BACKGROUND: Pneumonia is one of the major complications of drowning, but the optimal empirical antibiotic treatment is not clearly defined. Multidrug-resistant (MDR) bacteria and fungi have been identified in a recent series of freshwater drowning-associated pneumonia. However, microbial data in seawater drowning are scarce. The objective of the study is to describe the microorganisms isolated in early respiratory specimens obtained from seawater drowning-associated pneumonia and to provide their antibiotic susceptibility pattern. METHODS: All patients admitted for seawater drowning between 2003 and 2013 to two intensive care units, from the region in France with the highest drowning rate, were retrospectively included. Demographics, antimicrobial therapy and microbiological data from respiratory samples collected within the first 48 h after admittance were analyzed. RESULTS: Seventy-four drowned patients were included, of which 36 (49%) were diagnosed by the clinician as having early pneumonia. Concerning the overall population, the median simplified acute physiology score (version 2) was 45 (30-65), and the mortality was 26%. Twenty-four respiratory samples from different patients were obtained within the first 48 h. Sixteen were positive. The main microorganisms found were Enterobacteriaceae (Enterobacter spp., Klebsiella spp. and Escherichia coli) and Gram-positive aerobic cocci (Streptococcus pneumonia and Staphylococcus aureus) with a low rate of antimicrobial resistance. No MDR bacteria or fungi were identified. However, among the positive respiratory samples collected, 5/16 (31%) grew bacteria with natural resistance to amoxicillin-clavulanate, the first-line antibiotic commonly used in our cohort. Resistance was only found among Gram-negative bacteria and from respiratory samples of patients with a higher drowning grade at admission (p = 0.01). CONCLUSIONS: This 10-year descriptive study, the largest cohort to date, provides early respiratory samples from seawater drowning patients. The microorganisms retrieved were either mostly part of the human oro-pharyngeal flora or Enterobacteriaceae and displayed low rates of antimicrobial resistance. Respiratory samples should nonetheless be collected at admittance to the ICU to avoid inappropriate treatment. Empiric use of cephalosporin could be restricted to severe patients or if Gram-negative bacilli are found after direct examination.

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