Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests

Funding: Data collection was largely funded by the UK Natural Environment Research Council (NERC) project TREMOR (NE/N004655/1) to D.G., E.G. and O.P., with further funds from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES, finance code 001) to J.V.T. and a University of Leeds Climate Research Bursary Fund to J.V.T. D.G., E.G. and O.P. acknowledge further support from a NERC-funded consortium award (ARBOLES, NE/S011811/1). This paper is an outcome of J.V.T.’s doctoral thesis, which was sponsored by CAPES (GDE 99999.001293/2015-00). J.V.T. was previously supported by the NERC-funded ARBOLES project (NE/S011811/1) and is supported at present by the Swedish Research Council Vetenskapsrådet (grant no. 2019-03758 to R.M.). E.G., O.P. and D.G. acknowledge support from NERC-funded BIORED grant (NE/N012542/1). O.P. acknowledges support from an ERC Advanced Grant and a Royal Society Wolfson Research Merit Award. R.S.O. was supported by a CNPq productivity scholarship, the São Paulo Research Foundation (FAPESP-Microsoft 11/52072-0) and the US Department of Energy, project GoAmazon (FAPESP 2013/50531-2). M.M. acknowledges support from MINECO FUN2FUN (CGL2013-46808-R) and DRESS (CGL2017-89149-C2-1-R). C.S.-M., F.B.V. and P.R.L.B. were financed by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES, finance code 001). C.S.-M. received a scholarship from the Brazilian National Council for Scientific and Technological Development (CNPq 140353/2017-8) and CAPES (science without borders 88881.135316/2016-01). Y.M. acknowledges the Gordon and Betty Moore Foundation and ERC Advanced Investigator Grant (GEM-TRAITS, 321131) for supporting the Global Ecosystems Monitoring (GEM) network (gem.tropicalforests.ox.ac.uk), within which some of the field sites (KEN, TAM and ALP) are nested. The authors thank Brazil–USA Collaborative Research GoAmazon DOE-FAPESP-FAPEAM (FAPESP 2013/50533-5 to L.A.) and National Science Foundation (award DEB-1753973 to L. Alves). They thank Serrapilheira Serra-1709-18983 (to M.H.) and CNPq-PELD/POPA-441443/2016-8 (to L.G.) (P.I. Albertina Lima). They thank all the colleagues and grants mentioned elsewhere [8,36] that established, identified and measured the Amazon forest plots in the RAINFOR network analysed here. The authors particularly thank J. Lyod, S. Almeida, F. Brown, B. Vicenti, N. Silva and L. Alves. This work is an outcome approved Research Project no. 19 from ForestPlots.net, a collaborative initiative developed at the University of Leeds that unites researchers and the monitoring of their permanent plots from the world’s tropical forests [61]. The authros thank A. Levesley, K. Melgaço Ladvocat and G. Pickavance for ForestPlots.net management. They thank Y. Wang and J. Baker, respectively, for their help with the map and with the climatic data. The authors acknowledge the invaluable help of M. Brum for kindly providing the comparison of vulnerability curves based on PAD and on PLC shown in this manuscript. They thank J. Martinez-Vilalta for his comments on an early version of this manuscript. The authors also thank V. Hilares and the Asociación para la Investigación y Desarrollo Integral (AIDER, Puerto Maldonado, Peru); V. Saldaña and Instituto de Investigaciones de la Amazonía Peruana (IIAP) for local field campaign support in Peru; E. Chavez and Noel Kempff Natural History Museum for local field campaign support in Bolivia; ICMBio, INPA/NAPPA/LBA COOMFLONA (Cooperativa mista da Flona Tapajós) and T. I. Bragança-Marituba for the research support.Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, Ψ50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3-5, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters Ψ50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both Ψ50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth-mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.Publisher PDFPeer reviewe

Cultura de condrócitos para o uso terapêutico: reconstituição de cartilagem

A cartilagem articular é um tecido avascular com números limitados de condrócitos, com capacidade limitada de reparo após uma lesão aguda. As técnicas disponíveis atualmente para o tratamento de lesões de cartilagem articular podem resultar em alívio dos sintomas, mas não na regeneração do tecido lesado. A geração de um substituto biológico que recomponha a cartilagem articular nativa requer células vivas que sejam capazes de sintetizar e manter a matriz cartilaginosa. A engenharia de tecidos constitui recentemente uma metodologia para reconstrução de novos órgãos e tecidos que foram lesados e apresentam dificuldades na reparação. Um dos maiores avanços no campo da engenharia de tecidos e dentro da medicina ortopédica, tem sido, o recrutamento de tecido do próprio paciente, que são dissociados em células e cultivadas sobre suportes biológicos ou sintéticos conhecidos como scaffolds, para posterior realização de implante de condrócitos, com intuito de regenerar o tecido cartilaginoso lesado. Uma variedade de scaffolds como hidrogel e polímeros sintéticos, têm sido investigadas para a expansão dos condrócitos “in vitro” para o reparo da cartilagem lesada. Tais matrizes incluem: arcabouços à base de colágeno: gel de colágeno tipo I e II, esponjas de colágeno tipo II, ácido polilático e ácido poliglicólico, fibrina, óxido de polietileno, fibrina, peptídeos, alginato e gel de plaquetas. No presente trabalho desenvolvemos diferentes metodologias de cultura de condrócitos utilizando scaffold sintético “hidrogel de alginato” e biológico “gel de plaquetas” obtido a partir do Plasma Rico em Plaquetas - PRP, além da cultura de condrócitos em pellet tri-dimensional, objetivando encontrar a melhor metodologia para a realização de implantes de condrócitos. Como modelo experimental escolhemos coelhos, tanto para coleta da cartilagem articular...Articular cartilage is an avascular tissue with limited numbers of chondrocytes, and limited recuperative capacity after a severe lesion. The techniques currently available for treatment of articular cartilage lesions can result in relief of symptoms, but not in regeneration of injured tissue. The generation of biological substitute that would recompose native articular cartilage requires live cells capable of synthesizing and maintaining cartilaginous matrix. The engineering of tissues has recently constituted a methodology for constructing new organs and tissues that had been injured and present recuperative difficulties. One of the greatest advances in the field of tissue engineering, and within orthopedic medicine, has been the recruitment of tissue from the patient him- or herself, that are dissociated in cells and cultured on biological or synthetic supports, known as scaffolds, for subsequent realization of implantation of chondrocytes, in order to regenerate injured cartilaginous tissue. A variety of scaffolds, such as hydrogel and synthetic polymers, have been investigated for expansion of chondrocytes in vitro to repair injured cartilage. Such matrices include: collagen-based scaffolds: gel of collagen types I and II, sponges of collagen type II, polylactic acid and polyglycolic acid, fibrin, polyethylene oxide, peptides, alginate and gel of platelets. In the present work we developed different methodologies of chondrocyte culture utilizing the synthetic scaffold “alginate hydrogel” and biological “gel of platelets” obtained from Platelet-Rich Plasma - PRP, in addition to chondrocyte culture in a tri-dimensional pellet, aiming to find the best methodology for accomplishing chondrocyte implants. We chose rabbits for the experimental model, as much for collection of articular cartilage as for obtaining blood plasma and realization of allogenic implants... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Gel de plaquetas: arcabouço 3D para cultura celular

INTRODUÇÃO: O reparo tissular é o objetivo final da cirurgia. A cultura celular requer arcabouço mecânico que dê suporte ao crescimento celular e difusão dos nutrientes. O uso do plasma rico em plaquetas (PRP) como um arcabouço 3D possui diversas vantagens: é material biológico, de fácil absorção pós-transplante, rico em fatores de crescimento, em especial PDGF- ββ e TGF-β que estimula síntese de matriz extracelular na cartilagem. OBJETIVO: Desenvolver arcabouço 3D à base de PRP. MATERIAIS E MÉTODOS: Duas formas foram idealizadas: Sphere e Carpet. Condições estéreis foram utilizadas. O gel de plaquetas permaneceu em cultura celular, observado diariamente em microscópio invertido. RESULTADOS: Ambos arcabouços obtiveram sucesso, com aspectos positivos e negativos. DISCUSSÃO: A forma Sphere não aderiu ao plástico. Observou-se retração do gel e investigação ao microscópio dificultada devido às áreas opacas no campo visual. A forma Carpet não aderiu ao plástico e apresentou-se translúcida. O tempo de estudo foi de 20 dias. CONCLUSÕES: A produção de um arcabouço 3D PRP foi um sucesso, e trata-se de uma alternativa que necessita ser mais utilizado e investigado para que se consolide em uma rota eficiente e confiável na tecnologia de engenharia tissular, particularmente em cultura de tecido cartilaginoso.INTRODUCTION: Tissue repair has been the ultimate goal of surgery. Cell culture requires a mechanical scaffold that supports cell growth and nutrient diffusion. Using platelet-rich plasma (PRP) as a 3D scaffold presents various advantages: it is a biological material, easily absorbed after transplantation, rich in growth factors, in particular, PDGF-ββ and TGF-β that stimulate extracellular matrix synthesis in cartilage culture. OBJECTIVE: To develop a PRP 3D scaffold. Material and METHODS: Two forms were idealized: Sphere and Carpet. Sterile conditions were used. The platelet gel remained in culture conditions, observed at an inverted microscope on a daily basis. RESULTS: Both forms were successful because they produced a 3D environment that supports cell growth, with positive and negative features. DISCUSSION: The Sphere form didn't attach to the plate. Gel retraction was observed and the investigation at the microscope was difficult, because of the opaque areas in the optical field. The Carpet form didn't retract, and didn't produce opaque areas. Follow-up time was 20 days. CONCLUSIONS: The production of a PRP 3D scaffold was successful, and this is an alternative requiring further investigation in order to establish an efficient and reliable route in tissue engineering technology, particularly in cartilage tissue culture

Terapia celular em modelo experimental de doença inflamatória intestinal

Inflammatory bowel disease, which mainly involves Crohn's disease and ulcerative rectocolitis, is an inflammatory condition of the mucosa that can afflict any segment of the gastrointestinal tract. Despite the fact that the existing therapies result in improvement in patient's symptomatology and quality of life, there is no curative treatment. Surgical treatment involves complex procedures associated with high morbidity and mortality rates. In this context, cell therapy with stem cells has emerged as a treatment with broad potential applicability. In this study, we intended to verify the efficacy of transplantation of adipose tissue-derived stem cells in rats with intestinal inflammation induced by trinitrobenzenesulfonic acid. The cell population was isolated from the adipose tissue of inguinal region of rats and processed for culture by mechanical dissociation. The animals were evaluated with respect to clinical and biochemical aspects, as well as by macroscopic, microscopic and histological analyses. In the experimental model of bowel inflammation by 2,4,6-trinitrobenzenesulfonic acid, the infusion of adipose tissue significantly reduced the presence of adhesions in the colon and adjacent organs and decreased the activity of myeloperoxidase, a marker of neutrophil infiltration in the injured mucosa. The results suggest that cell therapy with adipose tissue can promote and/or accelerate the regeneration of damaged intestinal mucosa. It is concluded that the presence of adhesions and the determination of myeloperoxidase activity provide indications that adipose tissue can promote and/or accelerate the regeneration of inflammatory bowel mucosa.A Doença Inflamatória Intestinal (DII), consistindo principalmente da doença de Crohn e retocolite ulcerativa, é uma condição inflamatória da mucosa que pode acometer qualquer segmento do trato gastrointestinal. Apesar das terapias existentes resultarem na melhora dos sintomas e da qualidade de vida dos pacientes, não há nenhum tratamento curativo. O tratamento cirúrgico envolve procedimentos complexos associados a altas taxas de morbimortalidade. Neste contexto, a terapia celular com células-tronco desponta como opção de tratamento potencialmente promissora. Em função destes aspectos, pretendeu-se, no presente estudo, verificar a eficácia do transplante de células-tronco derivadas do tecido adiposo (ASC) em ratos com inflamação intestinal induzida por ácido trinitrobenzenosulfonico (TNBS). As ASCs foram obtidas por dissociação mecânica do tecido adiposo da região inguinal de ratos e processadas para cultivo. Os animais foram avaliados, considerando-se os aspectos clínicos e bioquímicos, além de análises macroscópica, microscópica e histológica. No modelo de inflamação intestinal induzida por TNBS, a infusão de ASCs reduziu significativamente a presença de aderências entre o cólon e órgãos adjacentes, bem como diminuiu a atividade da mieloperoxidase (MPO), um marcador da infiltração de neutrófilos na mucosa lesada. Os resultados obtidos permitem concluir que a terapia celular com ASCs pode promover e/ou acelerar o processo de regeneração da mucosa intestinal inflamada

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora