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1.
An Acad Bras Cienc ; 94(1): e20201079, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35476061

RESUMO

The South Brazilian grasslands (Campos Sulinos) form the dominant vegetation in southern Brazil. They are species-rich ecosystems that occur under distinct geomorphological and climatic conditions but spatial variation of plant species diversity remains understudied. Here, we present a detailed description of plant communities across the region. Our data were obtained in 1080 plots, representing well-preserved grasslands in different ecological systems. Apart from describing alpha and beta diversity, we investigated the relations of plant communities with environmental features. We identified 759 plant species and found clear differences in community composition across the region. Northern and Southern highland grasslands, humid and dry coastal grasslands and the mesic Pampa grassland were clearly distinct, related to climatic and edaphic features. While species abundance distribution was markedly uneven, local species richness was high, above 20 species/m2, especially in the highlands and in mesic Pampa sites, on shallow soils. The predominant component of beta diversity was species turnover, which suggests that a network of well-conserved grasslands distributed across the region would be the best strategy to protect plant diversity. Our results establish regionalized reference values for richness and diversity that can be useful for initiatives of restoration and conservation of these grasslands.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Brasil , Plantas , Valores de Referência
2.
An Acad Bras Cienc ; 93(2): e20201604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852672

RESUMO

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.


Assuntos
Biodiversidade , Ecossistema , Brasil , Conservação dos Recursos Naturais , Humanos , Conhecimento
3.
Food Chem Toxicol ; 134: 110809, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31499124

RESUMO

The role of caffeinated beverages on efficiency of acute inflammatory responses is not yet fully understood. This study analyzed the effect of five hot water extracts, coffee (CO), black/green tea (BT/GT), yerba mate (YM), and guarana (GU) on inflammatory modulation of non-activated human peripheral blood mononuclear cells (PBMCs), yeast-activated human neutrophils, and granulocytic coelomocytes from Eisenia fetida earthworm. Based on preliminary tests, a concentration of 10 µg/mL was chosen for subsequent assays, as at this concentration, the extracts exhibited antioxidant, genoprotective, and non-cytotoxic properties. Immunoassays using 24-h PBMC supernatant showed that all extracts decreased levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ), and increased levels of the anti-inflammatory cytokine, IL-10. Further, these extracts induced overexpression of cytokine genes in 24-h cultures. These results suggest that an increase in the levels of mRNAs and/or inactive cytokines in the cytoplasm improves the "immune cytokine response. Analysis of the yeast encapsulation processes, and production of human neutrophils and coelomocyte extracellular DNA traps suggests that extracts also improve the immune response in humans and earthworms. However, for E. fetida, the intensity of these results varied from extract. Overall, our results suggest that caffeinated beverages may improve an organism's efficiency against acute inflammatory processes.


Assuntos
Bebidas , Cafeína/farmacologia , Inflamação/prevenção & controle , Leucócitos Mononucleares/efeitos dos fármacos , Animais , Citocinas/imunologia , Humanos , Mediadores da Inflamação/imunologia , Leucócitos Mononucleares/imunologia , Oligoquetos
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