Pervasive gaps in Amazonian ecological research

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

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

Low dose of dichloroacetate infusion reduces blood lactate after submaximal exercise in horses Baixa dose de infusão de dicloroacetato reduz o lactato sanguíneo após exercício submáximo em cavalos

The acute administration of an indirect activator of the enzyme pyruvate dehydrogenase (PDH) in human athletes causes a reduction in blood lactate level during and after exercise. A single IV dose (2.5m.kg-1) of dichloroacetate (DCA) was administered before a submaximal incremental exercise test (IET) with five velocity steps, from 5.0 m.s-1 for 1 min to 6.0, 6.5, 7.0 and 7.5m.s-1 every 30s in four untrained mares. The blood collections were done in the period after exercise, at times 1, 3, 5, 10, 15 and 20 min. Blood lactate and glucose (mM) were determined electro-enzymatically utilizing a YSI 2300 automated analyzer. There was a 15.3% decrease in mean total blood lactate determined from the values obtained at all assessment times in both trials after the exercise. There was a decrease in blood lactate 1, 3, 5, 10, 15 and 20 min after exercise for the mares that received prior DCA treatment, with respective mean values of 6.31±0.90 vs 5.81±0.50, 6.45±1.19 vs 5.58±1.06, 6.07±1.56 vs 5.26±1.12, 4.88±1.61 vs 3.95±1.00, 3.66±1.41 vs 2.86±0.75 and 2.75±0.51 vs 2.04±0.30. There was no difference in glucose concentrations. By means of linear regression analysis, V140, V160, V180 and V200 were determined (velocity at which the rate heart is 140, 160, 180, and 200 beats/minute, respectively). The velocities related to heart rate did not differ, indicating that there was no ergogenic effect, but prior administration of a relatively low dose of DCA in mares reduced lactatemia after an IET.<br>A administração aguda de um ativador indireto da enzima piruvato desidrogenase (PD) em atletas da espécie humana provoca redução na concentração de lactato sanguíneo durante e após exercício. Uma dose única, intravenosa de 2.5m.kg-1 de dicloroacetato (DCA) foi administrada antes de um exercício teste incremental submáximo (ETI) com cinco etapas de velocidade sendo 5,0 ms-1 por 1 minuto e 6,0, 6,5, 7,0, e 7,5 ms-1 a cada 30 segundos em quatro éguas destreinadas. As coletas de sangue foram realizadas no período após o exercício, nos momentos de 1, 3, 5, 10, 15 e 20 min. Lactato e glicose (mM) foram determinados electro-enzimaticamente utilizando um analisador automático (YSI 2300). Houve redução de 15,3% no lactato sanguíneo total médio que foi determinado a partir dos valores obtidos em todos os momentos de avaliação em ambos os testes, após o exercício. Houve diminuição na lactatemia 1, 3, 5, 10, 15 e 20 minutos após exercício para as éguas que receberam infusão de DCA, com os respectivos valores médios de 6,31±0,90 versus 5,81±0,50, 6,45±1,19 versus 5,58±1,06, 6,07±1,56 versus 5,26±1,12, 4,88±1,61 versus 3,95±1,00, 3,66±1,41 versus 2,86±0,75 e 2,75±0,51 versus 2,04±0,30. Não houve diferença nas concentrações de glicose. Por meio de análise de regressão linear, V140, V160, V180 e V200 foram determinados (velocidades em que as taxas cardíacas alcançam 140, 160, 180 e 200 bpm, respectivamente). As velocidades relacionadas com a frequência cardíaca não diferiram, indicando que não houve efeito ergogênico, mas a administração prévia de uma dose relativamente baixa de DCA em éguas reduziu a lactatemia após um ETI

Técnica para avaliação da pressão arterial pulmonar de equinos durante o exercício progressivo em esteira rolante Technique for pulmonary arterial pressure measurement in horses during the incremental exercise on a treadmill

Objetivou-se ilustrar a técnica cirúrgica de implantação de introdutores para cateter de Swan Ganz na veia jugular, bem como o procedimento de canulação da artéria pulmonar de dez equinos adultos sem raça definida (SRD). Realizando medidas através do cateter de Swan Ganz implantado, objetivou-se ainda demonstrar os valores de pressão arterial pulmonar (PAP) durante um teste de esforço progressivo de intensidade submáxima realizado em esteira rolante. A técnica cirúrgica de implantação de introdutores para o cateter de Swan Ganz empregada, demonstrou-se de fácil e rápida realização. Os animais não apresentaram complicações frente ao introdutor implantado e o teste ergométrico foi realizado conforme proposto. A PAP se elevou ao longo do exercício seguindo o incremento de velocidade, sendo os maiores valores médios observados nos momentos de maior intensidade do esforço. Os valores médios de PAP aumentaram (p<0,05) às velocidades de 7,5m/s (39±3 mmHg) e 8,5m/s (41±3 mmHg), quando comparados aos valores mensurados no repouso (26±3mmHg). Entretanto, os valores de PAP encontrados no máximo de esforço realizado pelos equinos SRD deste ensaio (41±3mmHg), encontram-se abaixo dos valores descritos para outras raças para a mesma intensidade de esforço. A descrição detalhada da técnica ilustrada no presente trabalho, pode contribuir substancialmente na padronização de protocolos experimentais que propõem o acesso arterial pulmonar por meio da implantação de cateter de Swan Ganz em equinos. O teste ergométrico proposto foi eficaz em promover variações de PAP de acordo com o esforço realizado, demonstrando valores para equinos SRD que poderão ser usados como base para futuras avaliações.<br>The aim of this study was to illustrate the surgical implantation of Swan Ganz introducers into the jugular vein, as well as the pulmonary artery cannulation procedure using ten mixed breed (MB) adult horses. We also proposed to demonstrate pulmonary arterial pressure (PAP) values measured through the implanted Swan Ganz during one incremental submaximal exercise test performed on a treadmill. Surgical implantation of the Swan Ganz introducers has demonstrated to be easy and quick to perform. None of the animals showed signs of discomfort following the surgery and ergometric test was carried out as proposed. PAP increased proportionally with exercise intensity, and the major average values were recorded at the higher effort time points. The PAP average values increased (P<0.05) when treadmill speed reached 7.5m/s (39±3mmHg) and 8.5m/s (41±3mmHg), comparing to average values at rest (26±3mmHg). However, the PAP values observed at the maximal effort performed by the MB horses of this trial (41±3mmHg), are under the values described for other breeds at similar effort tests. The technique described in the present study contributes for the standardization of research protocols using arterial pulmonary access via Swan Ganz catheter implantation in horses. The ergometric test was effective to promote PAP changes according to the effort, showing PAP values for MB horses that can guide further investigations

Técnica para avaliação da pressão arterial pulmonar de equinos durante o exercício progressivo em esteira rolante

Objetivou-se ilustrar a técnica cirúrgica de implantação de introdutores para cateter de Swan Ganz na veia jugular, bem como o procedimento de canulação da artéria pulmonar de dez equinos adultos sem raça definida (SRD). Realizando medidas através do cateter de Swan Ganz implantado, objetivou-se ainda demonstrar os valores de pressão arterial pulmonar (PAP) durante um teste de esforço progressivo de intensidade submáxima realizado em esteira rolante. A técnica cirúrgica de implantação de introdutores para o cateter de Swan Ganz empregada, demonstrou-se de fácil e rápida realização. Os animais não apresentaram complicações frente ao introdutor implantado e o teste ergométrico foi realizado conforme proposto. A PAP se elevou ao longo do exercício seguindo o incremento de velocidade, sendo os maiores valores médios observados nos momentos de maior intensidade do esforço. Os valores médios de PAP aumentaram (p<0,05) às velocidades de 7,5m/s (39±3 mmHg) e 8,5m/s (41±3 mmHg), quando comparados aos valores mensurados no repouso (26±3mmHg). Entretanto, os valores de PAP encontrados no máximo de esforço realizado pelos equinos SRD deste ensaio (41±3mmHg), encontram-se abaixo dos valores descritos para outras raças para a mesma intensidade de esforço. A descrição detalhada da técnica ilustrada no presente trabalho, pode contribuir substancialmente na padronização de protocolos experimentais que propõem o acesso arterial pulmonar por meio da implantação de cateter de Swan Ganz em equinos. O teste ergométrico proposto foi eficaz em promover variações de PAP de acordo com o esforço realizado, demonstrando valores para equinos SRD que poderão ser usados como base para futuras avaliações.The aim of this study was to illustrate the surgical implantation of Swan Ganz introducers into the jugular vein, as well as the pulmonary artery cannulation procedure using ten mixed breed (MB) adult horses. We also proposed to demonstrate pulmonary arterial pressure (PAP) values measured through the implanted Swan Ganz during one incremental submaximal exercise test performed on a treadmill. Surgical implantation of the Swan Ganz introducers has demonstrated to be easy and quick to perform. None of the animals showed signs of discomfort following the surgery and ergometric test was carried out as proposed. PAP increased proportionally with exercise intensity, and the major average values were recorded at the higher effort time points. The PAP average values increased (P<0.05) when treadmill speed reached 7.5m/s (39±3mmHg) and 8.5m/s (41±3mmHg), comparing to average values at rest (26±3mmHg). However, the PAP values observed at the maximal effort performed by the MB horses of this trial (41±3mmHg), are under the values described for other breeds at similar effort tests. The technique described in the present study contributes for the standardization of research protocols using arterial pulmonary access via Swan Ganz catheter implantation in horses. The ergometric test was effective to promote PAP changes according to the effort, showing PAP values for MB horses that can guide further investigations.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Physiological Concentrations of Acute-Phase Proteins and Immunoglobulins in Equine Synovial Fluid

Synovial fluid (SF) is capable of reflecting infectious, immunological, or inflammatory joint conditions in horses by altering its composition and appearance. Although plasma and SF compositions are quantitatively different, this latter compartment reflects changes in plasma macromolecules. Therefore, changes in serum immunoglobulin protein concentrations tend also to alter intracapsular levels. Therefore, it is necessary to know the physiological concentrations of proteins present in SF. The aim of this study was to determine the levels of total protein, albumin, transferrin, haptoglobin, α1-acid glycoprotein, ceruloplasmin, and immunoglobulins A and G in SF of six healthy horses. The synovial proteinogram was obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The SF proteins reached a maximum of 25% of serum concentrations, varying inversely with molecular weight of the protein, except for the ceruloplasmin. © 2013 Elsevier Inc

Low dose of dichloroacetate infusion reduces blood lactate after submaximal exercise in horses

The acute administration of an indirect activator of the enzyme pyruvate dehydroge-nase (PDH) in human athletes causes a reduction in blood lactate level during and after exercise. A single IV dose (2.5m.kg-1) of dichloroacetate (DCA) was administered before a submaximal incremental exercise test (IET) with five velocity steps, from 5.0 m.s-1 for 1 min to 6.0, 6.5, 7.0 and 7.5m.s-1 every 30s in four untrained mares. The blood collections were done in the period after exercise, at times 1, 3, 5, 10, 15 and 20 min. Blood lactate and glucose (mM) were determined electro-enzymatically utilizing a YSI 2300 automated analyzer. There was a 15.3% decrease in mean total blood lactate determined from the values obtained at all assessment times in both trials after the exercise. There was a decrease in blood lactate 1, 3, 5, 10, 15 and 20 min after exercise for the mares that received prior DCA treatment, with respective mean values of 6.31±0.90 vs 5.81±0.50, 6.45±1.19 vs 5.58±1.06, 6.07±1.56 vs 5.26±1.12, 4.88±1.61 vs 3.95±1.00, 3.66±1.41 vs 2.86±0.75 and 2.75±0.51 vs 2.04±0.30. There was no difference in glucose concentrations. By means of linear regression analysis, V140, V160, V180 and V200 were determined (velocity at which the rate heart is 140, 160, 180, and 200 beats/minute, respectively). The velocities related to heart rate did not differ, indicating that there was no ergogenic effect, but prior administration of a relatively low dose of DCA in mares reduced lactatemia after an IET