Perfil lipídico, factores de riesgo cardiovascular y síndrome metabólico en un grupo de pacientes con SID

BACKGROUND: Since the advent of AIDS, the anti-HIV therapy has developed significantly, including the highly active antiretroviral therapy (HAART) and the disease acquired a chronic characteristic. However, after the introduction of HAART, several metabolic alterations were observed, mainly related to the lipid profile. OBJECTIVES: to evaluate and compare lipid profiles, analyze cardiovascular risk, describe the prevalence of metabolic syndrome in AIDS patients with or without HAART. METHODS: Over an 18-month period, 319 patients treated at outpatient clinics in the city of São Paulo, Brazil were selected. RESULTS: The final sample included 215 patients receiving HAART and 69 HAART-naive patients. The mean age was 39.5 years, and 60.9% were males. The main cardiovascular risk factors were smoking (27%), hypertension (18%) and family history of atherosclerosis (40%). Mean total cholesterol, HDL-cholesterol, triglycerides and glucose were higher in the HAART group than in the non-HAART group (205 vs 180 mg/dl, 51 vs 43 mg/dl, 219 vs 164 mg/dl and 101 vs 93 mg/dl respectively; p < 0.001 for all). According to the Framingham risk score, the cardiovascular risk was moderate to high in 11% of the patients receiving HAART and 4% of the HAART-naïve patients. According to the Adult Treatment Panel III definition, the metabolic syndrome was observed in 13% and 12% of the patients with or without HAART, respectively. CONCLUSIONS: Although the mean values for total cholesterol, HDL-c and triglycerides were higher in the HAART group, a higher cardiovascular risk was not identified in the former. The prevalence of metabolic syndrome was comparable in both groups.FUNDAMENTO: Desde el surgimiento del SIDA, la terapia antiretroviral se desarrolló significantemente. Al incluir la terapia antiretroviral altamente activa (HAART), la enfermedad adquirió una característica crónica. Sin embargo, tras la introducción de HAART, diversas alteraciones metabólicas se observaron, principalmente relacionadas al perfil lipídico. OBJETIVO: Evaluar y comparar los perfiles lipídicos, analizar el riesgo cardiovascular, y describir la prevalencia del síndrome metabólico en pacientes con SIDA tratados o no con HAART. MÉTODOS: Durante un período de 18 meses, se seleccionaron a 319 pacientes tratados en ambulatorios en la ciudad de São Paulo, Brasil. RESULTADOS: La muestra final incluyó a 215 pacientes tratados con HAART y a 69 pacientes vírgenes de tratamiento con HAART. La edad promedio era de 39,5 años, y el 60,9% eran del sexo masculino. Los principales factores de riesgo cardiovascular eran el fumo (27%), hipertensión (18%) e histórico familiar de aterosclerosis (40%). Los valores promedios de colesterol total, HDL-colesterol, triglicéridos y glucosa fueron más altos en el Grupo HAART que en el Grupo no-HAART (205 vs. 180 mg/dL, 51 vs. 43 mg/dL, 219 vs. 164 mg/dL, 101 vs. 93 mg/dL respectivamente; p < 0,001 para todos). De conformidad con el score de riesgo de Framingham, el riesgo cardiovascular era moderado y alto en el 11% de los pacientes tratados con HAART y el 4% de los pacientes no-HAART. Según la definición del Adult Treatment Panel III, el síndrome metabólico se observó en el 13% y el 12% de los pacientes, respectivamente, con y sin HAART. CONCLUSIÓN: Aunque los valores promedios del colesterol total, HDL-c y triglicéridos fueron más altos en el Grupo HAART, un mayor riesgo cardiovascular no se identificó en el primer grupo. La prevalencia de síndrome metabólico fue comparable en ambos grupos.FUNDAMENTO: Desde o advento da AIDS, a terapia antiretroviral desenvolveu-se significantemente, incluindo a terapia antiretroviral altamente ativa (HAART) e a doença adquiriu uma característica crônica. Entretanto, após a introdução da HAART, várias alterações metabólicas foram observadas, principalmente relacionadas ao perfil lipídico. OBJETIVO: Avaliar e comparar os perfis lipídicos, analisar o risco cardiovascular, e descrever a prevalência da síndrome metabólica em pacientes com AIDS tratados ou não com HAART. MÉTODOS: Durante um período de 18 meses, 319 pacientes tratados em ambulatórios na cidade de São Paulo, Brasil, foram selecionados. RESULTADOS: A amostra final incluiu 215 pacientes tratados com HAART e 69 pacientes virgens de tratamento com HAART. A idade média era 39,5 anos, e 60,9% eram do sexo masculino. Os principais fatores de risco cardiovascular eram o fumo (27%), hipertensão (18%) e histórico familiar de aterosclerose (40%). Os valores médios de colesterol total, HDL-colesterol, triglicérides e glicose foram mais altos no grupo HAART do que no grupo não-HAART (205 vs 180 mg/dl, 51 vs 43 mg/dl, 219 vs 164 mg/dl e 101 vs 93 mg/dl respectivamente; p < 0,001 para todos). De acordo com o escore de risco de Framingham, o risco cardiovascular era moderado a alto em 11% dos pacientes tratados com HAART e 4% dos pacientes não-HAART. De acordo com a definição do Adult Treatment Panel III, a síndrome metabólica foi observada em 13% e 12% dos pacientes, respectivamente, com e sem HAART. CONCLUSÃO: Embora os valores médios do colesterol total, HDL-c e triglicérides tenham sido mais altos no grupo HAART, um maior risco cardiovascular não foi identificado no primeiro grupo. A prevalência de síndrome metabólica foi comparável em ambos os grupos.Universidade Federal de São Paulo (UNIFESP)Secretaria Municipal de Saúde de São PauloUNIFESPSciEL

Direct evidence for phosphorus limitation on Amazon forest productivity

The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.The authors acknowledge funding from the UK Natural Environment Research Council (NERC), grant number NE/L007223/1. This is publication 850 in the technical series of the BDFFP. C.A.Q. acknowledges the grants from Brazilian National Council for Scientific and Technological Development (CNPq) CNPq/LBA 68/2013, CNPq/MCTI/FNDCT no. 18/2021 and his productivity grant. C.A.Q., H.F.V.C., F.D.S., I.A., L.F.L., E.O.M. and S.G. acknowledge the AmazonFACE programme for financial support in cooperation with Coordination for the Improvement of Higher Education Personnel (CAPES) and the National Institute of Amazonian Research as part of the grants CAPES-INPA/88887.154643/2017-00 and 88881.154644/2017-01. T.F.D. acknowledges funds from FundacAo de Amparo a Pesquisa do Estado de SAo Paulo (FAPESP), grant 2015/50488-5, and the Partnership for Enhanced Engagement in Research (PEER) programme grant AID-OAA-A-11-00012. L.E.O.C.A. thanks CNPq (314416/2020-0)

Evolutionary Heritage Influences Amazon Tree Ecology

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change

Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models

Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs

Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models

This is the final version of the article. Available from Wiley via the DOI in this record.Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs.This paper is a product of the European Union's Seventh Framework Programme AMAZALERT project (282664). The field data used in this study have been generated by the RAINFOR network, which has been supported by a Gordon and Betty Moore Foundation grant, the European Union's Seventh Framework Programme projects 283080, ‘GEOCARBON’; and 282664, ‘AMAZALERT’; ERC grant ‘Tropical Forests in the Changing Earth System’), and Natural Environment Research Council (NERC) Urgency, Consortium and Standard Grants ‘AMAZONICA’ (NE/F005806/1), ‘TROBIT’ (NE/D005590/1) and ‘Niche Evolution of South American Trees’ (NE/I028122/1). Additional data were included from the Tropical Ecology Assessment and Monitoring (TEAM) Network – a collaboration between Conservation International, the Missouri Botanical Garden, the Smithsonian Institution and the Wildlife Conservation Society, and partly funded by these institutions, the Gordon and Betty Moore Foundation, and other donors. Fieldwork was also partially supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico of Brazil (CNPq), project Programa de Pesquisas Ecológicas de Longa Duração (PELD-403725/2012-7). A.R. acknowledges funding from the Helmholtz Alliance ‘Remote Sensing and Earth System Dynamics’; L.P., M.P.C. E.A. and M.T. are partially funded by the EU FP7 project ‘ROBIN’ (283093), with co-funding for E.A. from the Dutch Ministry of Economic Affairs (KB-14-003-030); B.C. [was supported in part by the US DOE (BER) NGEE-Tropics project (subcontract to LANL). O.L.P. is supported by an ERC Advanced Grant and is a Royal Society-Wolfson Research Merit Award holder. P.M. acknowledges support from ARC grant FT110100457 and NERC grants NE/J011002/1, and T.R.B. acknowledges support from a Leverhulme Trust Research Fellowship

Hyperdominance in Amazonian Forest Carbon Cycling

While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region

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

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 &lt;= 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

Porous alumina-spinel ceramics for high temperature applications

In order to reduce energy costs, high-temperature insulation porous refractory ceramics have been subjected to increasing demands. Among the techniques used to produce these materials (such as the addition of foaming agents and organic compounds), the pore generation via phase transformation presents key aspects, such as easy processing and the absence of toxic volatiles. In this study, this technique was applied to produce porous ceramics by decomposing an aluminum magnesium hydro-carbonate known as hydrotalcite (Mg(6)Al(2)(CO(3))(OH)(16)center dot 4H(2)O). It was found out that by using this complex compound, a large fraction of pores can be generated and kept at high temperatures (above 1300 degrees C) due to the in situ formation of spinel-like phases (MgAl(2)O(4)). (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.FAPESPCNPqAlcoa Aluminum (Brazil

Gelcasting of alumina-chitosan beads

Several papers have reported the advantageous combination of chitosan and ceramic particles for such applications as biomimetic scaffolds, membranes, pollution remediation and gelcasting complex shapes. This work presents a novel gelcasting consolidation mechanism, based on the effects of pH changes on chitosan solubility and zeta potential of alumina particles. Unlike other chitosan-based gelcasting methods, it employs a small content of organic material (lower than 3 wt%) and does not require crosslinking agents (such as glutaraldehyde). With this new method alumina beads with 0.5-1 mm diameter could be produced, whose porosity and specific surface area could be tuned for various applications. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.FAPESPCNP

Imbalance between endothelial progenitors cells and microparticles in HIV-infected patients naive for antiretroviral therapy

Background: Cardiovascular events have been reported among HIV-infected patients following antiretroviral therapy. However, the role of HIV itself in determining vascular damage is less described. Chronic inflammatory state might impair some regulatory endothelium properties leading to its activation, apoptosis or erosion.Objectives: To evaluate the balance between endothelial progenitor cells and micro-particles in HIV-infected antiretroviral drug-naive patients.Design: A case-control study comparing HIV-infected patients (n = 35) with sex-matched and age-matched healthy controls (n = 33).Methods: Endothelial progenitor cells populations expressing CD34(+), CD133(+) and KDR(+) were quantified by flow cytometry. Endothelial-derived microparticles, expressing CD51(+), and platelet-derived microparticles, expressing CD31(+)/CD42(+), were also measured. Endothelial function was estimated by flow-mediated dilation.Results: Lower percentages of endothelial progenitor cells (CD34(+)/KDR(+)) were observed in HIV-infected individuals compared with controls (0.02 vs. 0.09%, P = 0.045). in addition, endothelial microparticles concentration was higher in HIV-infected individuals (1963 vs. 436 microparticles/ml platelet-poor plasma, P = 0.003), with similar number of platelet-derived microparticles among groups. Furthermore, flow-mediated dilation was lower among HIV-infected individuals compared with controls [mean (SEM): 10 (1) and 16% (2), respectively; P = 0.03].Conclusion: Our findings suggest an imbalance between endothelial progenitor cells mobilization and endothelial apoptosis. the alteration in the turnover of endothelial cells may contribute to cardiovascular events in HIV-infected patients. (C) 2011 Wolters Kluwer Health | Lippincott Williams & WilkinsFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilUniversidade Federal de São Paulo, Cardiovasc Div, Lipids Atherosclerosis & Vasc Biol Sect, São Paulo, BrazilUniversidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilUniversidade Federal de São Paulo, Cardiovasc Div, Lipids Atherosclerosis & Vasc Biol Sect, São Paulo, BrazilFAPESP: 2008/55223-6Web of Scienc