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1.
Glob Chang Biol ; 30(1)2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273552

RESUMO

We created a database of lost and rediscovered tetrapod species, identified patterns in their distribution and factors influencing rediscovery. Tetrapod species are being lost at a faster rate than they are being rediscovered, due to slowing rates of rediscovery for amphibians, birds and mammals, and rapid rates of loss for reptiles. Finding lost species and preventing future losses should therefore be a conservation priority. By comparing the taxonomic and spatial distribution of lost and rediscovered tetrapod species, we have identified regions and taxa with many lost species in comparison to those that have been rediscovered-our results may help to prioritise search effort to find them. By identifying factors that influence rediscovery, we have improved our ability to broadly distinguish the types of species that are likely to be found from those that are not (because they are likely to be extinct). Some lost species, particularly those that are small and perceived to be uncharismatic, may have been neglected in terms of conservation effort, and other lost species may be hard to find due to their intrinsic characteristics and the characteristics of the environments they occupy (e.g. nocturnal species, fossorial species and species occupying habitats that are more difficult to survey such as wetlands). These lost species may genuinely await rediscovery. However, other lost species that possess characteristics associated with rediscovery (e.g. large species) and that are also associated with factors that negatively influence rediscovery (e.g. those occupying small islands) are more likely to be extinct. Our results may foster pragmatic search protocols that prioritise lost species likely to still exist.


Assuntos
Ecossistema , Extinção Biológica , Animais , Anfíbios , Áreas Alagadas , Mamíferos , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Biodiversidade
2.
Glob Chang Biol ; 29(24): 6900-6911, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37804212

RESUMO

The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.


Assuntos
Ecossistema , Gado , Animais , Humanos , Conservação dos Recursos Naturais , Mamíferos , Florestas
3.
Conserv Biol ; 35(6): 1833-1849, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34289517

RESUMO

Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard.


RESUMEN: Reconociendo que era imperativo evaluar la recuperación de especies y el impacto de la conservación, la Unión Internacional para la Conservación de la Naturaleza (UICN) convocó en 2012 al desarrollo de una "Lista Verde de Especies" (ahora el Estatus Verde de las Especies de la UICN). Un marco de referencia preliminar de una Lista Verde de Especies para evaluar el progreso de las especies hacia la recuperación, publicado en 2018, proponía 2 componentes separados pero interconectados: un método estandarizado (i.e., medición en relación con puntos de referencia de la viabilidad de especies, funcionalidad y distribución antes del impacto) para determinar el estatus de recuperación actual (puntuación de recuperación de la especie) y la aplicación de ese método para estimar impactos en el pasado y potenciales de conservación basados en 4 medidas (legado de conservación, dependencia de conservación, ganancia de conservación y potencial de recuperación). Probamos el marco de referencia con 181 especies representantes de diversos taxa, historias de vida, biomas, y categorías (riesgo de extinción) en la Lista Roja de la IUCN. Con base en la distribución observada de la puntuación de recuperación de las especies, proponemos las siguientes categorías de recuperación de la especie: totalmente recuperada, ligeramente mermada, moderadamente mermada, mayormente mermada, gravemente mermada, extinta en estado silvestre, e inderterminada. Cincuenta y nueve por ciento de las especies se consideraron mayormente o gravemente mermada. Aunque hubo una relación negativa entre el riesgo de extinción y la puntuación de recuperación de la especie, la variación fue considerable. Algunas especies en las categorías de riesgo bajas fueron evaluadas como más lejos de recuperarse que aquellas con alto riesgo. Esto enfatiza que la recuperación de especies es diferente conceptualmente al riesgo de extinción y refuerza la utilidad del Estado Verde de las Especies de la UICN para comprender integralmente el estatus de conservación de especies. Aunque el riesgo de extinción no predijo el legado de conservación, la dependencia de conservación o la ganancia de conservación, se correlacionó positivamente con la potencial de recuperación. Solo 1.7% de las especies probadas fue categorizado como cero en los 4 indicadores de impacto de la conservación, lo que indica que la conservación ha jugado, o jugará, un papel en la mejoría o mantenimiento del estatus de la especie la gran mayoría de ellas. Con base en nuestros resultados, diseñamos una versión actualizada del marco de referencia para la evaluación que introduce la opción de utilizar una línea de base dinámica para evaluar los impactos futuros de la conservación en el corto plazo y redefine corto plazo como 10 años.


Assuntos
Espécies em Perigo de Extinção , Extinção Biológica , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Risco
4.
Conserv Biol ; 34(3): 561-571, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31621946

RESUMO

Species interactions matter to conservation. Setting an ambitious recovery target for a species requires considering the size, density, and demographic structure of its populations such that they fulfill the interactions, roles, and functions of the species in the ecosystems in which they are embedded. A recently proposed framework for an International Union for Conservation of Nature Green List of Species formalizes this requirement by defining a fully recovered species in terms of representation, viability, and functionality. Defining and quantifying ecological function from the viewpoint of species recovery is challenging in concept and application, but also an opportunity to insert ecological theory into conservation practice. We propose 2 complementary approaches to assessing a species' ecological functions: confirmation (listing interactions of the species, identifying ecological processes and other species involved in these interactions, and quantifying the extent to which the species contributes to the identified ecological process) and elimination (inferring functionality by ruling out symptoms of reduced functionality, analogous to the red-list approach that focuses on symptoms of reduced viability). Despite the challenges, incorporation of functionality into species recovery planning is possible in most cases and it is essential to a conservation vision that goes beyond preventing extinctions and aims to restore a species to levels beyond what is required for its viability. This vision focuses on conservation and recovery at the species level and sees species as embedded in ecosystems, influencing and being influenced by the processes in those ecosystems. Thus, it connects and integrates conservation at the species and ecosystem levels.


Evaluación de la Función Ecológica en el Contexto de Recuperación de Especies Resumen Las interacciones entre especies son de importancia para la conservación. La definición de una meta ambiciosa de recuperación para una especie requiere considerar el tamaño, la densidad y la estructura demográfica de sus poblaciones de tal manera que lleven a cabo las interacciones, papeles y funciones de las especies en los ecosistemas donde viven. Un marco de referencia propuesto recientemente para una Lista Verde de Especies de la Unión Internacional para la Conservación de la Naturaleza (UICN)formaliza este requerimiento mediante la definición de una especie completamente recuperada en términos de su representación, viabilidad y funcionalidad. La definición y cuantificación de la función ecológica desde la perspectiva de la recuperación de especies es un reto conceptual y de aplicación, pero también es un oportunidad para insertar la teoría ecológica en la práctica de la conservación. Proponemos 2 métodos complementarios para evaluar las funciones ecológicas de una especie: confirmación (listado de interacciones de la especie, identificación de procesos ecológicos y otras especies involucradas en estas interacciones) y eliminación (inferencia de la funcionalidad descartando los síntomas de reducción en la funcionalidad, análogo al método de la lista roja que enfoca los síntomas de reducción en la viabilidad). A pesar de los retos, la incorporación de la funcionalidad en la planificación de la recuperación de especies es posible en la mayoría de los casos y es esencial para una visión de la conservación que vaya más allá de la prevención de extinciones y que tenga como objetivo restaurar a una especie a niveles más allá de lo que se requiere para su viabilidad. Su visión se centra en la conservación y recuperación a nivel de especies y ve a las especies como componentes de los ecosistemas, influyendo y siendo influenciadas por los procesos en esos ecosistemas. Así, conecta e integra la conservación a nivel de especies y ecosistemas.


Assuntos
Ecossistema , Espécies em Perigo de Extinção , Animais , Biodiversidade , Conservação dos Recursos Naturais
5.
Conserv Biol ; 33(5): 1106-1119, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30767306

RESUMO

As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.


Un Marco de Trabajo para Medir el Estado Salvaje de Poblaciones de Vertebrados Mayores bajo Manejo Resumen Conforme los paisajes siguen cayendo bajo la influencia del humano por causa de la pérdida del hábitat y la fragmentación, cada vez se usa más el encercado para mitigar las amenazas antropogénicas o incrementar el valor comercial de la fauna. La intensificación subsecuente del manejo tiene el potencial para erosionar el estado salvaje al desincorporar a las poblaciones de los procesos a nivel de paisaje, desconectando así a las especies del proceso de selección natural. Por lo tanto, se necesitan herramientas para medir el grado al cual las poblaciones de especies de vertebrados mayores dentro de áreas de fauna protegidas y privadas son autosostenibles y libres de adaptarse. Diseñamos un marco de trabajo para medir dicho estado salvaje con base en seis atributos relacionados con las dinámicas evolutivas y ecológicas de los vertebrados (espacio, resistencia a las enfermedades y a los parásitos, exposición a la depredación, exposición a las limitaciones y fluctuaciones en las reservas de agua y alimentos, y reproducción). Para cada atributo, establecimos umbrales empíricos y específicos por especie entre cinco estados salvajes basados en las intervenciones de manejo cuantificables. Usamos datos de 205 propiedades privadas de fauna con objetivos de manejo que abarcan desde el ecoturismo hasta el uso para consumo para probar el marco de trabajo en seis especies de herbívoros con una gama de estados de conservación y valores comerciales. Los puntajes de estado salvaje entre las especies difirieron significativamente y la proporción de poblaciones identificadas como salvajes osciló del 12% al 84%, lo que indica que la herramienta detectó diferencias a escala de sitio entre las poblaciones de diferentes especies y las poblaciones de la misma especie bajo diferentes regímenes de manejo. Si cuantificamos el estado salvaje, este marco de trabajo les proporciona a los practicantes las unidades de medida estandarizadas que vinculan a la biodiversidad con el uso sostenible de la fauna. Las aplicaciones de este marco de trabajo incluyen informar a los planes de manejo de las especies a escalas locales; estandarizar la inclusión de las poblaciones manejadas en las evaluaciones de listas rojas; y proporcionar una plataforma para la certificación y regulación de las economías basadas en la fauna. La aplicación de este marco de trabajo puede ayudar a insertar a la fauna como un valor normativo dentro de la política y a mitigar la línea base cambiante de lo que significa conservar verdaderamente a una especie.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Animais Selvagens , Ecossistema , Humanos , Vertebrados
6.
Transpl Infect Dis ; 21(4): e13104, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31077542

RESUMO

INTRODUCTION: Infection is one of the most significant complications following heart transplantation (HT). The aim of this study was to identify specific risk factors for early postoperative infections in HT recipients, and to develop a multivariable predictive model to identify HT recipients at high risk. METHODS: A single-center, observational, and retrospective study was conducted. The dependent variable was in-hospital postoperative infection. We examined demographic and epidemiological data from donors and recipients, surgical features, and adverse postoperative events as independent variables. Backwards, stepwise multivariable logistic regression with a P-value < 0.05 was used to identify clinical factors independently associated with the risk of in-hospital postoperative infections following HT. RESULTS: Six hundred seventy-seven patients were included in this study. During the in-hospital postoperative period, 348 episodes of infection were diagnosed in 239 (35.9%) patients. Seven variables were identified as independent clinical predictors of early postoperative infection after HT: history of diabetes mellitus, previous sternotomy, preoperative mechanical ventilation, primary graft failure, major surgical bleeding, use of mycophenolate mofetil, and use of itraconazole. Based on the results of multivariable models, we constructed a 7-variable (8-point) score to predict the risk of in-hospital postoperative infection in HT recipients, which showed a reasonable ability to predict the risk of in-hospital postoperative infection in this population. Prospective external validation of this new score is warranted to confirm its clinical applicability. CONCLUSIONS: In-hospital postoperative infection is a common complication after HT, affecting 35% of patients who underwent this procedure at our institution. Diabetes mellitus, previous sternotomy, preoperative mechanical ventilation, primary graft failure, major surgical bleeding, use of mycophenolate mofetil, and itraconazole were all independent clinical predictors of early postoperative infection after HT.


Assuntos
Infecções Bacterianas/epidemiologia , Infecção Hospitalar/epidemiologia , Transplante de Coração/efeitos adversos , Complicações Pós-Operatórias/microbiologia , Adulto , Idoso , Infecção Hospitalar/microbiologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco
7.
Ecol Appl ; 28(2): 275-283, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29222956

RESUMO

Effective reintroduction strategies require accurate estimates of vital rates and the factors that influence them. The hirola (Beatragus hunteri) is the rarest antelope on Earth, with a global population size of <500 individuals restricted to the Kenya-Somali border. We estimated vital rates of hirola populations exposed to varying levels of predation and rangeland quality from 2012 to 2015, and then built population matrices to estimate the finite rate of population change (λ) and demographic sensitivities. Mean survival for all age classes and population growth was highest in the low-predation-high-rangeland-quality setting (λ = 1.08 ± 0.03 [mean ± SE]), and lowest in the high-predation-low-rangeland-quality setting (λ = 0.70 ± 0.22). Retrospective demographic analyses revealed that increased fecundity (the number of female calves born to adult females annually) and female calf survival were responsible for higher population growth where large carnivores were absent. In contrast, variation in adult female survival was the primary contributor to differences in population growth attributable to rangeland quality. Our analyses suggest that hirola demography is driven by a combination of top-down (predation) and bottom-up (rangeland quality) forces, with populations in the contemporary geographic range impacted both by declining rangeland quality and predation. To enhance the chances of successful reintroductions, conservationists can consider rangeland restoration to boost both the survival and fecundity of adult females within the hirola's historical range.


Assuntos
Antílopes , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Animais , Feminino , Quênia , Dinâmica Populacional , Somália
8.
Conserv Biol ; 32(5): 1128-1138, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29578251

RESUMO

Stopping declines in biodiversity is critically important, but it is only a first step toward achieving more ambitious conservation goals. The absence of an objective and practical definition of species recovery that is applicable across taxonomic groups leads to inconsistent targets in recovery plans and frustrates reporting and maximization of conservation impact. We devised a framework for comprehensively assessing species recovery and conservation success. We propose a definition of a fully recovered species that emphasizes viability, ecological functionality, and representation; and use counterfactual approaches to quantify degree of recovery. This allowed us to calculate a set of 4 conservation metrics that demonstrate impacts of conservation efforts to date (conservation legacy); identify dependence of a species on conservation actions (conservation dependence); quantify expected gains resulting from conservation action in the medium term (conservation gain); and specify requirements to achieve maximum plausible recovery over the long term (recovery potential). These metrics can incentivize the establishment and achievement of ambitious conservation targets. We illustrate their use by applying the framework to a vertebrate, an invertebrate, and a woody and an herbaceous plant. Our approach is a preliminary framework for an International Union for Conservation of Nature (IUCN) Green List of Species, which was mandated by a resolution of IUCN members in 2012. Although there are several challenges in applying our proposed framework to a wide range of species, we believe its further development, implementation, and integration with the IUCN Red List of Threatened Species will help catalyze a positive and ambitious vision for conservation that will drive sustained conservation action.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Animais , Biodiversidade , Coleta de Dados , Vertebrados
9.
Circ J ; 82(5): 1351-1359, 2018 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-29618707

RESUMO

BACKGROUND: Heart transplantation (HT) is a well-established lifesaving treatment for endstage cardiac failure. Antibody-mediated rejection (AMR) represents one of the main problems after HT because of its diagnostic complexity and the poor evidence for supporting treatments. Complement cascade and B-cells play a key role in AMR and contribute to graft damage. This study explored the importance of variants in genes related to complement pathway and B-cell biology in HT and AMR in donors and in donor-recipient pairs.Methods and Results:Genetic variants in 112 genes (51 complement and 61 B-cell biology genes) were analyzed on next-generation sequencing in 28 donor-recipient pairs, 14 recipients with and 14 recipients without AMR. Statistical analysis was performed with SNPStats, R, and EPIDAT3.1. We identified one single nucleotide polymorphism (SNP) in donors in genes related to B-cell biology,interleukin-4 receptor subunitα (p.Ile75Val-IL4Rα), which correlated with the development of AMR. Moreover, in the analysis of recipient-donor genotype discrepancies, we identified another SNP, in this case inadenosine deaminase(ADA; p.Val178(p=)), which was related to B-cell biology, associated with the absence of AMR. CONCLUSIONS: Donor polymorphisms and recipient-donor discrepancies in genes related to the biology of B-cells, could have an important role in the development of AMR. In contrast, no variants in donor or in donor-recipient pairs in complement pathways seem to have an impact on AMR.


Assuntos
Linfócitos B , Rejeição de Enxerto , Transplante de Coração , Sequenciamento de Nucleotídeos em Larga Escala , Isoanticorpos/imunologia , Polimorfismo de Nucleotídeo Único , Doadores de Tecidos , Adulto , Linfócitos B/imunologia , Linfócitos B/patologia , Feminino , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade
10.
Curr Opin Cardiol ; 32(3): 308-315, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28306671

RESUMO

PURPOSE OF REVIEW: Recent years have seen advances in the early detection of cardiac graft rejection. RECENT FINDINGS: We review the possibilities offered by tissue Doppler imaging and speckle tracking echocardiography, cardiac magnetic resonance, cardiac computed tomography, single positron emission tomography, gene expression profiling, and quantitation of donor-derived cell-free DNA, and microRNAs. SUMMARY: Noninvasive monitoring of acute and chronic rejection after cardiac transplantation is an unmet need and remains a challenge. Imaging techniques and peripheral blood biomarkers are the most commonly used approaches, and in recent years there has been great progress. Gene expression profiling seems to be useful for ruling out the presence of a moderate to severe acute cellular rejection in stable, low-risk patients. Newer monitoring tools, like donor-derived cell-free DNA or microRNA, seem to be promising for individualizing immunosuppressive therapies and better understanding the mechanisms of rejection.

11.
Conserv Biol ; 29(5): 1303-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25917114

RESUMO

Previous studies show that conservation actions have prevented extinctions, recovered populations, and reduced declining trends in global biodiversity. However, all studies to date have substantially underestimated the difference conservation action makes because they failed to account fully for what would have happened in the absence thereof. We undertook a scenario-based thought experiment to better quantify the effect conservation actions have had on the extinction risk of the world's 235 recognized ungulate species. We did so by comparing species' observed conservation status in 2008 with their estimated status under counterfactual scenarios in which conservation efforts ceased in 1996. We estimated that without conservation at least 148 species would have deteriorated by one International Union for Conservation of Nature (IUCN) Red List category, including 6 species that now would be listed as extinct or extinct in the wild. The overall decline in the conservation status of ungulates would have been nearly 8 times worse than observed. This trend would have been greater still if not for conservation on private lands. While some species have benefited from highly targeted interventions, such as reintroduction, most benefited collaterally from conservation such as habitat protection. We found that the difference conservation action makes to the conservation status of the world's ungulate species is likely to be higher than previously estimated. Increased, and sustained, investment could help achieve further improvements.


Assuntos
Artiodáctilos/fisiologia , Conservação dos Recursos Naturais , Extinção Biológica , Perissodáctilos/fisiologia , Mamífero Proboscídeo/fisiologia , Animais , Biodiversidade , Espécies em Perigo de Extinção , Risco
13.
Front Cardiovasc Med ; 11: 1349417, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525191

RESUMO

Introduction and objectives: Mitochondrial pyruvate carrier (MPC) mediates the entry of pyruvate into mitochondria, determining whether pyruvate is incorporated into the Krebs cycle or metabolized in the cytosol. In heart failure (HF), a large amount of pyruvate is metabolized to lactate in the cytosol rather than being oxidized inside the mitochondria. Thus, MPC activity or expression might play a key role in the fate of pyruvate during HF. The purpose of this work was to study the levels of the two subunits of this carrier, named MPC1 and MPC2, in human hearts with HF of different etiologies. Methods: Protein and mRNA expression analyses were conducted in cardiac tissues from three donor groups: patients with HF with reduced ejection fraction (HFrEF) with ischemic cardiomyopathy (ICM) or idiopathic dilated cardiomyopathy (IDC), and donors without cardiac pathology (Control). MPC2 plasma levels were determined by ELISA. Results: Significant reductions in the levels of MPC1, MPC2, and Sirtuin 3 (SIRT3) were observed in ICM patients compared with the levels in the Control group. However, no statistically significant differences were revealed in the analysis of MPC1 and MPC2 gene expression among the groups. Interestingly, Pyruvate dehydrogenase complex (PDH) subunits expression were increased in the ICM patients. In the case of IDC patients, a significant decrease in MPC1 was observed only when compared with the Control group. Notably, plasma MPC2 levels were found to be elevated in both disease groups compared with that in the Control group. Conclusion: Decreases in MPC1 and/or MPC2 levels were detected in the cardiac tissues of HFrEF patients, with ischemic or idiopatic origen, indicating a potential reduction in mitochondrial pyruvate uptake in the heart, which could be linked to unfavorable clinical features.

14.
Rev Esp Cardiol (Engl Ed) ; 77(4): 290-301, 2024 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37516313

RESUMO

INTRODUCTION AND OBJECTIVES: Repetitive ambulatory doses of levosimendan are an option as a bridge to heart transplantation (HT), but evidence regarding the safety and efficacy of this treatment is scarce. The objective of the LEVO-T Registry is to describe the profile of patients on the HT list receiving levosimendan, prescription patterns, and clinical outcomes compared with patients not on levosimendan. METHODS: We retrospectively reviewed all patients listed for elective HT from 2015 to 2020 from 14 centers in Spain. RESULTS: A total of 1015 consecutive patients were included, of whom 238 patients (23.4%) received levosimendan. Patients treated with levosimendan had more heart failure (HF) admissions in the previous year and a worse clinical profile. The most frequent prescription pattern were fixed doses triggered by the patients' clinical needs. Nonfatal ventricular arrhythmias occurred in 2 patients (0.8%). No differences in HF hospitalizations were found between patients who started levosimendan in the first 30 days after listing and those who did not (33.6% vs 34.5%; P=.848). Among those who did not, 102 patients (32.9%) crossed over to levosimendan after an HF admission. These patients had a rate of 0.57 HF admissions per month before starting levosimendan and 0.21 afterwards. Propensity score matching analysis showed no differences in survival at 1 year after listing between patients receiving levosimendan and those who did not (HR, 1.03; 95%CI, 0.36-2.97; P=.958) or in survival after HT (HR, 0.97; 95%CI, 0.60-1.56; P=.958). CONCLUSIONS: Repetitive levosimendan in an ambulatory setting as a bridge to heart transplantation is commonly used, is safe, and may reduce HF hospitalizations.


Assuntos
Insuficiência Cardíaca , Transplante de Coração , Piridazinas , Humanos , Simendana/uso terapêutico , Cardiotônicos/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/cirurgia , Hidrazonas/uso terapêutico , Piridazinas/uso terapêutico
15.
Transpl Immunol ; 76: 101771, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36473577

RESUMO

PURPOSE: To describe the evolution of the serum levels of soluble HLA-G (s-HLA-G) during the first 12 months after heart transplantation (HT) and to correlate it with clinical outcomes. METHODS: Observational study based in a single-center cohort of 59 patients who underwent HT between December-2003 and March-2010. Soluble HLA-G levels were measured from serum samples extracted before HT, and 1, 3, 6 and 12 months after HT. The cumulative burden of s-HLA-G expression during the first post-transplant year was assessed by means of the area under the curve (AUC) of s-HLA-G levels over time and correlated with the acute rejection burden -as assessed by a rejection score-, the presence of coronary allograft vasculopathy (CAV) grade ≥ 1 and infections during the first post-transplant year; as well as with long-term patient and graft survival. Mean follow-up was 12.4 years. RESULTS: Soluble HLA-G levels decreased over the first post-transplant year (p = 0.020). The AUC of s-HLA-G levels during the first post-transplant year was higher among patients with infections vs. those without infections (p = 0.006). No association was found between the AUC of s-HLA-G levels and the burden of acute rejection or the development of CAV. Overall long-term survival, long-term survival free of late graft failure and cancer-free survival were not significantly different in patients with an AUC of s-HLA-G levels higher or lower than the median of the study population. CONCLUSIONS: Soluble HLA-G levels decreased over the first year after HT. Higher HLA-G expression was associated with a higher frequency of infections, but not with the burden of acute rejection or the development of CAV, neither with long-term patient or graft survival.


Assuntos
Antígenos HLA-G , Avaliação de Resultados da Assistência ao Paciente , Transplantados , Humanos , Rejeição de Enxerto/metabolismo , Sobrevivência de Enxerto/fisiologia , Transplante de Coração/efeitos adversos , Antígenos HLA-G/sangue , Antígenos HLA-G/química
16.
J Am Coll Cardiol ; 82(9): 753-767, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37612006

RESUMO

BACKGROUND: The reported prevalence of donor-transmitted coronary artery disease (TCAD) in heart transplantation (HT) is variable, and its prognostic impact remains unclear. OBJECTIVES: The goal of this study was to characterize TCAD in a contemporary multicentric cohort and to study its prognostic relevance. METHODS: This was a retrospective study of consecutive patients >18 years old who underwent HT in 11 Spanish centers from 2008 to 2018. Only patients with a coronary angiography (c-angio) within the first 3 months after HT were studied. Significant TCAD (s-TCAD) was defined as any stenosis ≥50% in epicardial coronary arteries, and nonsignificant TCAD (ns-TCAD) as stenosis <50%. Clinical outcomes were assessed by means of Cox regression and competing risks regression. Patients were followed-up for a median period of 6.3 years after c-angio. RESULTS: From a cohort of 1,918 patients, 937 underwent c-angio. TCAD was found in 172 patients (18.3%): s-TCAD in 65 (6.9%) and ns-TCAD in 107 (11.4%). Multivariable Cox regression analysis did not show a statistically significant association between s-TCAD and all-cause mortality (adjusted HR: 1.44; 95% CI: 0.89-2.35; P = 0.141); however, it was an independent predictor of cardiovascular mortality (adjusted HR: 2.25; 95% CI: 1.20-4.19; P = 0.011) and the combined event cardiovascular death or nonfatal MACE (adjusted HR: 2.42; 95% CI: 1.52-3.85; P < 0.001). No statistically significant impact of ns-TCAD on clinical outcomes was detected. The results were similar when reassessed by means of competing risks regression. CONCLUSIONS: TCAD was not associated with reduced survival in patients alive and well enough to undergo post-HT angiography within the first 3 months; however, s-TCAD patients showed increased risk of cardiovascular death and MACE.


Assuntos
Doença da Artéria Coronariana , Transplante de Coração , Humanos , Adolescente , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/cirurgia , Constrição Patológica , Prevalência , Prognóstico , Estudos Retrospectivos , Angiografia Coronária , Transplante de Coração/efeitos adversos
17.
Ecol Evol ; 12(4): e8744, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35386872

RESUMO

Over the last 20 years, ecological restoration of degraded habitats has become common in conservation practice. Mountain hares (Lepus timidus scoticus) were surveyed during 2017-2021 using 830 km of line transects in the Peak District National Park, England. Historically degraded bog areas were previously reported having low hare numbers. Following bog restoration, we found hare densities of 32.6 individuals km-2, notably higher than neighboring degraded (unrestored) bog with 24.4 hares km-2. Hare density on restored peatland was 2.7 times higher than on bogs managed for grouse shooting at 12.2 hares km-2 and 3.3 times higher than on heather moorland managed for grouse shooting at 10.0 hares km-2. Yearly estimates varied most on habitats managed for grouse, perhaps indicative of the impact of habitat management, for example, heather burning and/or possible hare culling to control potential tick-borne louping ill virus in gamebirds. Acid grassland used for sheep farming had a similar density to grouse moorland at 11.8 hares km-2. Unmanaged dwarf shrub heath had the lowest density at 4.8 hares km-2. Hare populations are characterized by significant yearly fluctuations, those in the study area increasing by 60% between 2017 and 2018 before declining by ca. 15% by 2020 and remaining stable to 2021. During an earlier survey in 2002, total abundance throughout the Peak District National Park was estimated at 3361 (95% CI: 2431-4612) hares. The present study estimated 3562 (2291-5624) hares suggesting a stable population over the last two decades despite fluctuations likely influenced by weather and anthropogenic factors. Mountain hares in the Peak District favored bog habitats and were associated with restored peatland habitat. Wildlife management should be cognizant of hare density variation between habitats, which may have implications for local extinction risk.

18.
Eur J Intern Med ; 97: 86-94, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35000806

RESUMO

AIMS: In the absence of previous direct comparative studies, we aimed to evaluate the effectiveness of spironolactone and eplerenone in patients with heart failure and reduced ejection fraction (HFrEF) in a real-world clinical setting. METHODS: Using Fine-Gray´s competing risk regression, we compared the clinical outcomes of 293 patients with chronic HF and left ventricular ejection fraction <40% treated with eplerenone and 293 propensity-score matched individuals treated with spironolactone. Study subjects were selected from a prospective cohort of 1404 ambulatory patients with HFrEF seen since 2010 to 2019 in a single specialized HF clinic, among which 992 received a mineralocorticoid receptor antagonist at baseline. Median follow-up was 3.95 years. RESULTS: No statistically significant differences between patients treated with eplerenone versus spironolactone were observed with regard to the risk of the primary composite end-point cardiovascular death or HF hospitalization (HR 0.95; 95% CI 0.73-1.23; p= 0.677). However, eplerenone use was associated to lower cardiovascular mortality (HR 0.55; 95% CI 0.35-0.85; p= 0.008) and lower all-cause mortality (HR 0.67; 95% CI 0.47-0.95; p= 0.027). The incidence of drug suspension due to side effects (HR 0.58, 95% CI 0.40-0.85; p= 0.005) and drug suspension due to any reason (HR 0.70, 95% CI 0.51-0.97; p= 0.033) were lower among patients treated with eplerenone. CONCLUSIONS: In this observational, real-world, propensity-score matched study of patients with HFrEF, eplerenone was associated to lower cardiovascular mortality and lower all-cause mortality than spironolactone.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Eplerenona/farmacologia , Eplerenona/uso terapêutico , Humanos , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Estudos Prospectivos , Espironolactona/uso terapêutico , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
19.
Eur J Intern Med ; 105: 89-96, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36123281

RESUMO

AIMS: To assess the incidence of cancer diagnosis and cancer-related mortality in patients with heart failure (HF). METHODS: Observational study based in a prospective cohort of patients with HF referred to a specialized Spanish clinic between 2010 and 2019. The observed incidence of malignancies (excluding non-melanoma skin cancer) was compared to that expected for the general Spanish population according to the Global Cancer Observatory. RESULTS: We studied 1909 consecutive patients with HF. Over a median follow-up of 4.07 years, 165 new cases of malignancy were diagnosed. Observed age-standardized incidence rates of cancer were 861 (95% CI 618.4-2159.4) cases per 100,000 patients-years in men and 728.5 (95% CI 451.1-4308.7) cases per 100,000 patients-years in women; while age-standardized incidence rates of cancer expected for the general Spanish population were 479.4 cases per 100,000 patients-years in men (risk ratio = 1.80) and 295.5 cases per 100,000 patients-years in women (risk ratio = 2.46). Both a history of pre-existing malignancy at baseline and the development of new malignancies during follow-up were associated with reduced survival. Observed age-standardized cancer-related mortality was 344.1 (95% CI 202.1-1675) deaths per 100,000 patient-years in men and 217.0 (95% CI 32.8-3949.3) deaths per 100,000 patient-years in women; while age-standardized cancer-related mortality expected for the general Spanish population was 201.4 deaths per 100,000 patients-years in men (risk ratio = 1.71) and 96.2 deaths per 100,000 patients-years in women (risk ratio = 2.26). CONCLUSION: Patients with HF showed higher incidence rates of cancer diagnosis and cancer-related mortality than those expected for the general population.


Assuntos
Insuficiência Cardíaca , Neoplasias , Masculino , Humanos , Feminino , Incidência , Prognóstico , Estudos Prospectivos , Fatores de Risco , Insuficiência Cardíaca/epidemiologia , Neoplasias/epidemiologia
20.
ESC Heart Fail ; 8(3): 2002-2008, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33773098

RESUMO

AIMS: Maximum oxygen uptake (VO2max ) is an essential parameter to assess functional capacity of patients with heart failure (HF). We aimed to identify clinical factors that determine its value, as they have not been well characterized yet. METHODS: We conducted a retrospective, observational, single-centre study of 362 consecutive patients with HF who underwent cardiopulmonary exercise testing (CPET) as part of standard clinical assessment since 2009-2019. CPET was performed on treadmill, according to Bruce's protocol (n = 360) or Naughton's protocol (n = 2). We performed multivariable linear regression analyses in order to identify independent clinical predictors associated with peak VO2max . RESULTS: Mean age of study patients was 57.3 ± 10.9 years, mean left ventricular ejection fraction was 32.8 ± 14.2%, and mean VO2max was 19.8 ± 5.2 mL/kg/min. Eighty-nine (24.6%) patients were women, and 114 (31.5%) had ischaemic heart disease. Multivariable linear regression analysis identified six independent clinical predictors of VO2max , including NYHA class (B coefficient = -2.585; P < 0.001), age (B coefficient per 1 year = -0.104; P < 0.001), tricuspid annulus plane systolic excursion (B coefficient per 1 mm = +0.209; P < 0.001), body mass index (B coefficient per 1 kg/m2  = -0.172; P = 0.002), haemoglobin (B coefficient per 1 g/dL = +0.418; P = 0.007) and NT-proBNP (B coefficient per 1000 pg/mL = -0.142; P = 0.019). CONCLUSIONS: The severity of HF (NYHA class, NT-proBNP) as well as age, body composition and haemoglobin levels influence significantly exercise capacity. In patients with HF, the right ventricular systolic function is of greater importance for the physical capacity than the left ventricular systolic function.


Assuntos
Insuficiência Cardíaca , Consumo de Oxigênio , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Oxigênio , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
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