60 research outputs found
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
Os desafios do atendimento de pacientes com sequelas cardiovasculares decorrentes de trauma do tórax / Challenges in the care of patients with cardiovascular sequels resulting from chest trauma
Introdução: O tórax apresenta estruturas de diversos sistemas de sustentação da vida, dentre eles o respiratório e o cardiovascular. Por conter, estruturas nobres para a manutenção da vida, os potenciais para ocorrer lesões graves em decorrência de traumas são muito grandes, como dados mostram, 25% das mortes são secundárias a trauma torácico. Dentro deste contexto, questiona-se quais os desafios no atendimento de pacientes com sequelas cardiovasculares decorrentes de traumas torácicos? Portanto, esse estudo tem como objetivo identificar as dificuldades enfrentadas na assistência de saúde de pacientes com repercussões cardiovasculares devido a trauma de tórax, através da elaboração de um formulário baseado em revisão bibliográfica de dados da literatura científica publicados sobre esse tema. Metodologia: O trabalho baseia-se numa revisão integrativa de literatura, na qual foram analisados artigos publicados em revistas científicas, utilizando-se das bases de dados da BVS (Biblioteca Virtual da Saúde), como: Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde) e Scielo (Scientific Electronic Library Online). Resultados: Após as análises e seleção, restaram-se sete artigos para integrar a discussão. Os artigos selecionados, estão descritos na tabela, com autores, título, metodologia, resultados e conclusão. Em seguida, foi realizada uma discussão acerca destes artigos. Conclusão: Cada um dos casos revisados neste estudo demonstra a necessidade e a importância de acompanhamento cuidadoso de todos os pacientes que sofreram trauma torácico fechado, mesmo que a avaliação cardíaca inicial possa ser negativa.
Long-term thermal sensitivity of Earth’s tropical forests
The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (−9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth’s climate
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
Complete chloroplast genomes of six neotropical palm species, structural comparison, and evolutionary dynamic patterns
Abstract The Arecaceae family has a worldwide distribution, especially in tropical and subtropical regions. We sequenced the chloroplast genomes of Acrocomia intumescens and A. totai, widely used in the food and energy industries; Bactris gasipaes, important for palm heart; Copernicia alba and C. prunifera, worldwide known for wax utilization; and Syagrus romanzoffiana, of great ornamental potential. Copernicia spp. showed the largest chloroplast genomes (C. prunifera: 157,323 bp and C. alba: 157,192 bp), while S. romanzoffiana and B. gasipaes var. gasipaes presented the smallest (155,078 bp and 155,604 bp). Structurally, great synteny was detected among palms. Conservation was also observed in the distribution of single sequence repeats (SSR). Copernicia spp. presented less dispersed repeats, without occurrence in the small single copy (SSC). All RNA editing sites were C (cytidine) to U (uridine) conversions. Overall, closely phylogenetically related species shared more sites. Almost all nodes of the phylogenetic analysis showed a posterior probability (PP) of 1.0, reaffirming the close relationship between Acrocomia species. These results elucidate the conservation among palm chloroplast genomes, but point to subtle structural changes, providing support for the evolutionary dynamics of the Arecaceae family
The MASP Family of <em>Trypanosoma cruzi</em>: Changes in Gene Expression and Antigenic Profile during the Acute Phase of Experimental Infection
<div><h3>Background</h3><p><em>Trypanosoma cruzi</em> is the etiological agent of Chagas disease, a debilitating illness that affects millions of people in the Americas. A major finding of the <em>T. cruzi</em> genome project was the discovery of a novel multigene family composed of approximately 1,300 genes that encode mucin-associated surface proteins (MASPs). The high level of polymorphism of the MASP family associated with its localization at the surface of infective forms of the parasite suggests that MASP participates in host–parasite interactions. We speculate that the large repertoire of MASP sequences may contribute to the ability of <em>T. cruzi</em> to infect several host cell types and/or participate in host immune evasion mechanisms.</p> <h3>Methods</h3><p>By sequencing seven cDNA libraries, we analyzed the MASP expression profile in trypomastigotes derived from distinct host cells and after sequential passages in acutely infected mice. Additionally, to investigate the MASP antigenic profile, we performed B-cell epitope prediction on MASP proteins and designed a MASP-specific peptide array with 110 putative epitopes, which was screened with sera from acutely infected mice.</p> <h3>Findings and Conclusions</h3><p>We observed differential expression of a few MASP genes between trypomastigotes derived from epithelial and myoblast cell lines. The more pronounced MASP expression changes were observed between bloodstream and tissue-culture trypomastigotes and between bloodstream forms from sequential passages in acutely infected mice. Moreover, we demonstrated that different MASP members were expressed during the acute <em>T. cruzi</em> infection and constitute parasite antigens that are recognized by IgG and IgM antibodies. We also found that distinct MASP peptides could trigger different antibody responses and that the antibody level against a given peptide may vary after sequential passages in mice. We speculate that changes in the large repertoire of MASP antigenic peptides during an infection may contribute to the evasion of host immune responses during the acute phase of Chagas disease.</p> </div
Libraries codes of the trypomastigote samples.
<p>Libraries codes of the trypomastigote samples.</p
Screenings of MASP B-cell epitopes using SPOT peptide arrays.
<p>Blotting representative images using sera pools (n = 10) after 2, 10, and 12 passages in mice of CL-Bnener <i>T. cruzi</i>; predicted peptides were covalently synthesized in pre-activated cellulose membranes according to the SPOT synthesis technique (Frank <i>et al.</i>, 1992); circled spots: peptides with the highest Rd values.</p
Dendrogram of hierarchical analysis of MASP expression libraries.
<p>The uncertainty of the hierarchical cluster analysis of all expression libraries was calculated using Pvclust package <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0001779#pntd.0001779-Timenetsky1" target="_blank">[10]</a>. AU values (in red): approximately unbiased p-value.</p
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