1,029 research outputs found
LDL: from metabolic syndrome to instability of the atherosclerotic plaque
The dyslipidemia of the metabolic syndrome (MS) confers an elevated cardiovascular risk and is characterized by increased concentrations of triglycerides, decreased HDL-cholesterol and qualitative alterations in LDL which renders it more atherogenic, like the small dense LDL. Modified forms of LDL (mLDL) have been detected in vivo in the plasma and atherosclerotic plaques. A minor fraction of the total LDL has an electronegative charge and is represented by a heterogenic subpopulation of particles [LDL(-)], with higher potential to induce endothelial injury. It could be derived from oxidation, glication or other processes that alter its chemical composition and is increased in diabetic, hypercholesterolemic subjects, and in those with established coronary artery disease. mLDL are internalized by macrophages through scavenger receptors, originating foam cells and inducing an immune-inflammatory reaction. In the atherosclerotic process, the action of mLDL continues until plaque rupture and thrombogenesis, when it promotes apoptosis in endothelial and smooth muscle cells, and activates matrix metalloproteinases, weaken the fibrous cap, and further enhance the inflammatory process that ends in the thrombus formation. Development of new laboratory methods is necessary to enhance the clinical applicability of mLDL and the predictive power of the conventional lipid profile and other cardiovascular risk factors of the MS.A dislipidemia da síndrome metabólica (SM) confere elevado risco cardiovascular e caracteriza-se por aumento dos triglicérides, diminuição da HDL e alterações qualitativas da LDL, tornando-a mais aterogênica, como a LDL pequena e densa. LDLs modificadas (LDLm) foram detectadas in vivo no plasma e em placas ateroscleróticas. Uma pequena porcentagem do total de LDLs plasmáticas apresenta maior carga negativa na superfície [LDL(-)], sendo uma sub-população heterogênea de partículas com maior poder de agressão ao endotélio. Origina-se da oxidação, glicação ou outros processos que alteram sua composição química, estando aumentada em indivíduos diabéticos, hipercolesterolêmicos e naqueles com doença isquêmica cardíaca. A LDLm, ao ser fagocitada pelo receptor scavenger do macrófago, transforma-o numa célula espumosa e inicia uma reação imune-inflamatória. A participação da LDLm no processo aterogênico continua até a ruptura da placa e trombogênese, quando ela induz apoptose em células endoteliais e musculares lisas, aumenta a produção de metaloproteinases que digerem a matriz, fragilizando a cápsula, e exacerba a inflamação que concorre para o desenvolvimento do trombo. O aprimoramento dos ensaios laboratoriais para a LDLm permitirá maior aplicabilidade clínica, melhorando o poder preditivo de eventos cardiovasculares em relação ao perfil lipídico convencional e demais fatores de risco presentes na SM.UNIFESP-EPMUSP Faculdade de Ciências FarmacêuticasUSP Faculdade de Saúde Pública Departamento de NutriçãoUNIFESP, EPMSciEL
Interventions on the prevention of type 2 diabetes mellitus: is it feasible a population-based program in our country?
Considering the increasing prevalence of diabetes mellitus (DM) in underdeveloped countries as well as the simplicity of identifying individuals at high risk for such disease, implementation of intervention measures for its prevention is of great interest. Several studies have confirmed the benefits of lifestyle changes in preventing or postponig the progression from impaired glucose tolerance to DM. The review of these studies showed a 50% to 60% reduction in the incidence of DM by means of lifestyle modifications. Such results are better than those reported in studies in which pharmacological interventions were used with the same purpose. Despite the efficacy of lifestyle changes for the prevention of DM, compliance may represent a limitation to be implemented in communities. In our country, studies are necessary to assess the barriers for the implementation of a population-based program for the prevention of DM and other lifestyle related diseases in high-risk Brazilian subjects.A crescente prevalência de diabetes mellitus (DM) em países em desenvolvimento, associada à facilidade de se identificar indivíduos de alto risco para a doença, tornam interessante a idéia de se introduzir medidas que visem à prevenção da doença. Vários estudos comprovam os benefícios de mudanças no estilo de vida em prevenir ou retardar a progressão da tolerância à glicose diminuída para o DM. A revisão destes estudos mostra que é possível reduzir em 50 a 60% a incidência de DM intervindo-se no estilo de vida destes indivíduos, resultado superior ao obtido naqueles que, até o momento, utilizaram medidas farmacológicas com o mesmo objetivo. Apesar da eficácia destas simples medidas de prevenção por meio de mudanças no estilo de vida, estas são de difícil aderência e implementação em comunidades. Em nosso meio, são necessários estudos para avaliar as dificuldades de se implantar um programa nacional de prevenção de DM e outras doenças relacionadas ao estilo de vida em brasileiros de alto risco.Departamento de Medicina PreventivaUniversidade Federal de São Paulo (UNIFESP) Programa de Pós-Graduação em EndocrinologiaFleury - Centro de Medicina DiagnósticaUNIFESP, Programa de Pós-Graduação em EndocrinologiaSciEL
Micromorfologia foliar na análise da fitotoxidez por glyphosate em Eucalyptus grandis
Foram avaliados os efeitos da deriva de formulações comerciais de glyphosate sobre a superfície foliar e o crescimento de clones de eucalipto. Mudas de seis clones foram submetidas a 129,6 g ha-1 de glyphosate das formulações comerciais Scout®, Roundup NA®, Roundup transorb® e Zapp QI®. Entre os clones não foram identificadas diferenças quanto à tolerância ao glyphosate. Plantas expostas à deriva simulada de Roundup transorb® e Zapp QI® apresentaram, respectivamente, a maior e menor porcentagem de intoxicação. Observou-se menor massa seca em plantas expostas ao glyphosate, independentemente da formulação, e menor altura naquelas expostas ao Scout® e ao Roundup transorb®. As características quantitativas da superfície foliar não foram afetadas pelo glyphosate. As alterações micromorfológicas ocorreram na ausência de danos visíveis e foram observadas em ambas as faces da epiderme, em todos os clones avaliados. Danos como erosão e aspecto amorfo das ceras epicuticulares e infestação por hifas fúngicas ocorreram, independentemente da formulação utilizada. A avaliação anatômica da superfície foliar foi relevante para descrição e interpretação dos danos causados pelo glyphosate. Os dados de crescimento e de intoxicação indicam o Zapp QI® como a formulação de menor risco para a cultura do eucalipto quanto aos efeitos indesejáveis da deriva.The effects of commercial glyphosate drift on the leaf surface and growth of eucalypt clones were evaluated. Seedlings of six clones were submitted to 129.6 g ha-1 sub-rate of commercial glyphosate formulations Scout®, Roundup NA®, Roundup transorb® and Zapp QI®. No differences in tolerance to glyphosate were observed among the clones. Plants exposed to simulated drift of Roundup transorb® and Zapp QI® presented the highest and lowest intoxication percentages, respectively. Plants exposed to glyphosate reduced dry biomass, regardless of the formulation, and also reduced height of the plants exposed to Scout® and Roundup transorb®. Leaf surface characteristics were not affected by glyphosate application. However, the micromorphological damages occurred prior to the appearance of visible symptoms, and were observed on both faces of the epidermis, in all clones tested. Damages such as erosion and amorphous aspect of epicuticular waxes and infestation of fungal hyphae occurred, independently of the formulation used. The anatomical evaluation of the leaf surface effectively described the damages caused by glyphosate. The growth and intoxication data indicate Zapp QI® formulation as presenting the lowest risk to eucalypt culture, in relation to the undesirable herbicide drift effects
Spatial and temporal concentration of tourism demand in northern Portugal: regional policy recommendations to promote tourism competition and portofolio diversity
The northern region of Portugal, in the last years, has experienced a growing number of visitors from different countries, which may indicate the emergence of an overtourism phenomenon in some particular municipalities or specific spaces. This phenomenon may cause significant destruction of the living conditions of residents, landscapes, seascapes, air and water quality, causing economic inequalities and social exclusion. The concentration of tourism activity in different municipality regions can be measured with a well know concentration measured, the Herfindahl-Hirschman Index. Using as variables the number and nationality of visitors and their expenditures it is possible to follow the concentration of tourism visitors and expenditure, all over the 8 NUTIII regions located in the Northen of Portugal, and describe the routes of distribution of the tourism indicators from urban to rural areas following a more nature-oriented tourism. The results serve as a dipping compass for more oriented and well-targeted tourism policies.info:eu-repo/semantics/publishedVersio
Experimental analysis of flameless combustion for reduction of pollutants
Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.This report presents a special form of combustion, called flameless combustion. In contrast to the combustion within stabilized flames, temperature peaks can be avoided at flameless combustion. Critical points of this technology are the realization of thermofluodynamic conditions which stabilize the flameless combustion process and a design to reach flameless conditions. Burners for flameless combustion usually show complex geometries which make simplified schemes difficult and inappropriate. In this case, the present paper proposes a study to determine the viability of a flameless burner design for experimental investigation and a combustion chamber on a laboratorial scale able to use high temperature air to reduce pollutant emissions. During the experiments, it will be used natural gas and preheat air. The influence of the field flow, chamber temperature and preheating air temperature on reaction zone volume was examined using techniques capable of analyzing the temperature field in the combustor. The main conclusions were: a) in contrast to the flames, the combustion had low internal temperature gradients; b) the system has promoted changes in the volume characteristics of combustion significantly reducing pollutants: NOx, CO and UHC (Unburned Hydrocarbons); c) to same conditions no visible flame was observed during the test.dc201
Bibliometric analysis on the use of natural fibers in construction materials
Received: February 2nd, 2021 ; Accepted: August 3rd, 2021 ; Published: August 30th, 2021 ; Correspondence: [email protected] to the increasing interest of the population in the sustainability theme, there was
a consequent growth in publications related to the theme in the area of civil construction. Agroindustrial waste has become an environmental problem, and with that natural fibers have found
space in the reuse of waste due to its characteristics and possibilities of improving the mechanical
properties of its products. In order to achieve sustainable construction demand, along with the
need to reuse waste, studies have begun to analyze the application of natural fibers in construction
materials. The documents provided by the Web of Science (WOS) database through research
carried out with the search for the terms ‘Natural Fibers’ and ‘Building materials’ restricted to
the period 2010–2020 in the main WOS collection. The institutions involved with the
publications, the countries of origin of the documents, the year of publication, the keywords used
by the authors and the number of citations for each document were analyzed using bibliometrics
in the VOSVIEWER (VOS) software. The result of the analysis shows an increase in documents
related to the theme over the years, and that the countries with the most studies in the area are
China (16), USA (14) and Brazil (11), respectively. The results presented after analysis of the
keywords show that natural fiber (61 occurrences), mechanical properties (44 occurrences) and
composites (31 occurrences) are the words with the highest occurrence among the analyzed
documents. The present study shows the growth of research related to the theme, in addition to
discriminating countries, institutions and authors, which allows monitoring the scientific
expansion of the theme and guiding future studies
Nutritional value of meat lipid fraction from red-legged partridge (Alectoris rufa) obtained from wild and farmed specimens
Research Areas; Agriculture, Dairy & Animal ScienceArticle in International JournalABSTRACT - The red-legged partridge (Alectoris rufa) is a feathered game species of great socioeconomic importance in its native range and also in the UK. The aim of this study was to present a detailed comparison of meat's lipid fraction obtained from wild and farm-raised specimens and simultaneously compare the breast and leg meat portions.
Meat from wild specimens had a significant (P < 0.05) lower proportion of saturated fatty acid (less 5.1%) and presented better P/S and n-6/n-3 ratios, and atherogenicity index than farm-raised counterparts. The wild specimens presented significant (P < 0.001) higher contents of total vitamin E (8.8 vs. 2.2 mu g/g of fresh meat), is for that reason less prone to lipid peroxidation than farm-raised specimens.
Meat portions differed significantly (P < 0.05) on total lipid and total cholesterol contents and in all partial sums of fatty acids. The breast was leaner (0.86 vs. 1.47 g/100 g of meat), with lower total cholesterol (37.5 vs. 54.7 mg/100 g of meat), lower saturated fatty acid, monounsaturated fatty acid, polyunsaturated fatty acid, and n-6 polyunsaturated fatty acid (less 0.27, 0.28, 0.10, and 0.11 g/100 g of fresh meat, correspondingly). Regarding the fatty acid ratios and lipid quality indexes, breast meat presents better n-6/n-3 ratio and atherogenicity and thrombogenicity indexes.CIISAinfo:eu-repo/semantics/publishedVersio
A chromatographic network for the purification of detergent-solubilized six-transmembrane epithelial antigen of the prostate 1 from Komagataella pastoris mini-bioreactor lysates
Funding Information: The authors acknowledge the support from FEDER funds through the POCI-COMPETE 2020–Operational Programme Competitiveness and Internationalisation in Axis I–Strengthening Research, Technological Development and Innovation (Project POCI-01-0145-FEDER-007491), Jorge Barroca-Ferreira's and Ana M. Gonçalves's individual PhD Fellowships (SFRH/BD/130068/2017 and SFRH/BD/147519/2019, respectively), and Luís A. Passarinha's sabbatical fellowship (SFRH/BSAB/150376/2019) from FCT–Fundação para a Ciência e Tecnologia. This work was also supported by the Health Sciences Research Centre CICS-UBI (UIDB/00709/2020 and UIDP/00709/2020), the Applied Molecular Biosciences Unit UCIBIO (UIDB/04378/2020 and UIDP/04378/2020) and the Associate Laboratory Institute for Health and Bioeconomy–i4HB (project LA/P/0140/2020) which are financed by National Funds from FCT/MCTES. Publisher Copyright: © 2022The Six-Transmembrane Epithelial Antigen of the Prostate 1 (STEAP1) is an integral membrane protein involved in cellular communications, in the stimulation of cell proliferation by increasing Reactive Oxygen Species levels, and in the transmembrane-electron transport and reduction of extracellular metal-ion complexes. The STEAP1 is particularly over-expressed in prostate cancer, in contrast with non-tumoral tissues and vital organs, contributing to tumor progression and aggressiveness. However, the current understanding of STEAP1 lacks experimental data on the respective molecular mechanisms, structural determinants, and chemical modifications. This scenario highlights the relevance of exploring the biosynthesis of STEAP1 and its purification for further bio-interaction and structural characterization studies. In this work, recombinant hexahistidine-tagged human STEAP1 (rhSTEAP1-His6) was expressed in Komagataella pastoris (K. pastoris) mini-bioreactor methanol-induced cultures and successfully solubilized with Nonidet P-40 (NP-40) and n-Decyl-β-D-Maltopyranoside (DM) detergents. The fraction capacity of Phenyl-, Butyl-, and Octyl-Sepharose hydrophobic matrices were evaluated by manipulating the ionic strength of binding and elution steps. Alternatively, immobilized metal affinity chromatography packed with nickel or cobalt were also studied in the isolation of rhSTEAP1-His6 from lysate extracts. Overall, the Phenyl-Sepharose and Nickel-based resins provided the desired selectivity for rhSTEAP1-His6 capture from NP-40 and DM detergent-solubilized K. pastoris extracts, respectively. After a polishing step using the anion-exchanger Q-Sepharose, a highly pure, fully solubilized, and immunoreactive 35 kDa rhSTEAP1-His6 fraction was obtained. Altogether, the established reproducible strategy for the purification of rhSTEAP1-His6 paves the way to gather additional insights on structural, thermal, and environmental stability characterization significantly contributing for the elucidation of the functional role and oncogenic behavior of the STEAP1 in prostate cancer microenvironment.publishersversionpublishe
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