31 research outputs found

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Neurofibromatosis: chronological history and current issues

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Ubiquitous overexpression of a transgene encoding the extracellular portion of the Drosophila Roughest-Irregular Chiasm C protein induces early embryonic lethality

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    The cell adhesion molecule Rst-irreC is a transmembrane glycoprotein of the immunoglobulin superfamily involved in several important developmental processes in Drosophila, including axonal pathfinding in the optic lobe and programmed cell death and pigment cell differentiation in the pupal retina. As an initial step towards the "in vivo'' functional analysis of this protein we have generated transgenic fly stocks carrying a truncated cDNA construct encoding only the extracellular domain of Rst-IrreC under the transcriptional control of the heat shock inducible promoter hsp70. We show that heat-shocking embryos bearing the transgene during the first 8hs of development lead to a 3-4 fold reduction in their viability compared to wild type controls. The embryonic lethality can already be produced by applying the heat pulse in the first 3hs of embryonic development, does not seem to be suppressed in the absence of wildtype product and is progressively reduced as the heat treatment is applied later in embryogenesis. These results are compatible with the hypothesis of the lethal phenotype being primarily due to heterophilic interactions between Rst-IrreC extracellular domain and an yet unknown ligand

    Dislipidemia aterogénica en Latino América: prevalencia, causas y tratamiento

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    En las guías clínicas actuales, la dislipidemia aterogénica (DA) es una entidad no muy atendida. Debido a las frecuentes alteraciones en los lípidos asociados a la DA en Latino América (LA). Métodos: organizamos un grupo de expertos denominado Academia Latino Americana para el estudio de los Lípidos (ALALIP) para así generar un documento con análisis de su prevalencia y recomendaciones terapéuticas prácticas. Se utilizó la metodología Delphi modificada, con una revisión integral de la literatura y énfasis en las publicaciones con implicaciones para LA. Subsecuentemente, desarrollamos preguntas claves para ser discutidas. Resultados: En Latinoamérica (LA) no existe un estudio global sobre los factores de riesgo que representan a la totalidad de la población. El análisis sistemático de las encuestas nacionales de salud y de los estudios sistemáticos de cohorte muestran consistentemente una alta prevalencia de las anormalidades lipídicas que definen la DA. La concentración baja del colesterol unido a las lipoproteínas de alta densidad (C-HDL) varía entre 34,1% a 53,3% y la de triglicéridos (TG) elevados del 25,5% al 31,2%, con mayor prevalencia entre los hombres. La DA bien puede ser tratada con los cam- bios del estilo de vida (CTEV) como incremento en la actividad física, dieta baja en carbohidratos y alta en ácidos grasos poliinsaturados, tales como los ácidos grasos omega-3 como intervención primaria. De ser necesario, esta estrategia sera suplementada con terapia farmacológica como la monoterapia con estatinas o la combinación de fibratos/ácidos grasos omega-3. Conclusiones: Las anormalidades lipídicas que definen la DA tienen una elevada prevalencia en LA; su interacción con un estilo de vida no saludable, herencia y cambios epigenéticos están ligados a sus posibles causas. La DA es una causa importante de riesgo cardiovascular residual (RCVR) que debe ser diagnosticada y tratada. Es importante y necesario diseñar un estudio global de factores de riesgo en LA para conocer la real prevalencia de la DA.In the current clinical guidelines, atherogenic dyslipidemia (AD) is a poorly recognized entity. Due to the frequent lipid alterations associated with AD in Latin America (LA), we organized a group of experts named Latin American Academy for the study of Lipids (ALALIP), to generate a document to analize it ́s prevalence and to offer practical recommendations. Methodology: Using the Delphi methodology, we conducted a comprehensive literature review, with emphasis on those publications with implications for LA. Subsequently we develo- ped key questions to be discussed. Results: In LA There is no a global study on risk factors that repre- sent the entire population. The systematic analysis of national health surveys and regional cohort stu- dies showed a consistent high prevalence of the lipid abnormalities that define AD. Low high den- sity lipoprotein cholesterol (HDL-C) ranges from 34.1% to 53.3% and elevated triglycerides (TG) from 25.5% to 31.2% more prevalent in men. There are multiple causes: high consumption of foods with a high caloric density, cholesterol and trans fats, sedentary lifestyle and epigenetic changes. AD must be well treated with therapeutic changes in lifestyle with increase in physical activities, regular exercise and a diet with a low proportion of car- bohydrates and rich in poliunsatured fatty acid, such as omega-3 fatty acids as primary intervention. If needed, this strategy must be supplemented with pharmacological therapies such as monotherapy with statins or a combination of fibrates plus omega-3. fatty acid. Conclusions: Lipid abnormalities that define AD have a high prevalence in LA; the interaction between non-healthy lifestyle, inhe- ritance and epigenetic changes, possibly are the cause. AD is an important cause of cardiovascular residual risk (CVRR), that must be diagnosed and treated It is important and necesary to design a global study of risk factors in LA to know the true prevalence of AD
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