1,074 research outputs found

    Hyperglycemia and Hyperinsulinemia-Like Conditions Independently Induce Inflammatory Responses in Human Chondrocytes

    Get PDF
    To elucidate the mechanisms by which type 2 Diabetes Mellitus (DM2) constitutes a risk factor for the development and progression of osteoarthritis (OA), this work determined whether high glucose and/or high insulin, the hallmarks of DM2, are capable of activating the transcription factor, Nuclear Factor-κB (NF-κB), which plays a critical role in OA by inducing the expression of pro-inflammatory and catabolic genes. For this, we analyzed NF-κB activation by measuring the nuclear levels of p65 by western blot. As readouts of NF-κB activity, Interleukin-1β, Tumor Necrosis Factor-α, and inducible nitric oxide synthase (iNOS) expression were analyzed by real time RT-PCR and western blot. Culture of the human chondrocytic cell line, C28-I2, in high glucose (30 mM) increased nuclear NF-κB p65 levels in a time-dependent manner, relative to cells cultured in medium containing 10 mM glucose (regular culture medium). High glucose-induced NF-κB activation was inhibited by co-treatment with its specific inhibitor, Bay 11-7082, 5 µM. Culture of primary human chondrocytes under high glucose for 24 h increased IL-1β and TNF-α mRNA levels by 97% (p = 0.0066) and 85% (p = 0.0045), respectively, while iNOS mRNA and protein levels and NO production increased by 61% (p = 0.0017), 148% (p = 0.0089), and 70% (p = 0.049), respectively, relative to chondrocytes maintained in 10 mM glucose. Treatment of chondrocytic cells with 100 nM insulin was also sufficient to increase nuclear NF-κB p65 levels, independently of the glucose concentration in the culture medium. This study shows that hyperglycemia and hyperinsulinemia are independently sufficient to induce inflammatory responses in human chondrocytes, namely by activating NF-κB. This can be a relevant mechanism by which DM type 2 and other conditions associated with impaired glucose and insulin homeostasis, like obesity and the metabolic syndrome, contribute to the development and progression of OA.info:eu-repo/semantics/publishedVersio

    Do different sites in the same river have similar Trichoptera assemblages?

    Get PDF
    During the summer of 2001, trichoptera larvae were sampled with a kick-net in 15 sites belonging to 3 rivers of the Mondego River basin, in central-north Portugal. Simultaneously, 42 environmental variables were evaluated for each site. Twenty five species and genera of caddisflies were identified. The objective was to assess if trichoptera assemblages within a river tended to be more similar among each other than between rivers, giving the physical continuity of the habitat. Localities showed low segregation between all samples (MDS, CLUSTER and ANOSIM). The Alva River samples had the higher number of taxa and animals while the Ceira River samples had the lowest values. In terms of environmental characteristics, PCA showed high similarities between samples of the same river. However there was not total segregation of rivers. BIOENV analysis identified the set of parameters that best explain trichopteran associations per river. For the rivers, these variables were all related to habitat (e.g. pool quality, depth, substrate quality). The differences between the Alva and Ceira rivers seem to be related to the deterioration of the water quality in the Ceira river (increasing levels of sulphate, chloride and % of industrial, urban and degraded areas), which increased down the river.Durante el verano de 2001 se capturaron larvas de tricópteros en 15 puntos de muestreo pertenecientes a 3 ríos de la cuenca hidrográfica del Mondego, en el centro-norte de Portugal. Los muestreos fueron realizados con una red de mano (tipo "kicknet") y, simultáneamente, se evaluaron 42 variables ambientales para cada localidad. En total fueron identificadas 25 especies de tricópteros. El objetivo del estudio era evaluar si, dada la continuidad físico-química del habitat, las asociaciones de tricópteros de las localidades situadas en un mismo río son más semejantes entre sí que las pertenecientes a localidades de ríos diferentes. Los locales se presentaran poco segregados de acuerdo con los análisis MDS, CLUSTER y ANOSIM. Las muestras del río Alva tuvieron un número más elevado de taxa y animales mientras que las muestras del río Ceira tuvieron los valores más bajos. Desde el punto de vista ambiental el PCA reveló que las muestras de un mismo río eran más semejantes entre si. Sin embargo, no hubo segregación completa de ríos. El análisis BIOENV identificó el grupo de parámetros que mejor explican las asociaciones de tricópteros por río. Para los ríos, esas variables estaban todas relacionadas con el hábitat (e.g., calidad de las zonas lénticas, calidad de substrato y profundidad). Las diferencias entre los ríos Alva y Ceira parecen ser debidas al empeoramiento de la calidad de las aguas del río Ceira (mayores niveles de sulfato, cloro y porcentaje de degradación industrial y urbana) que aumentan río abajo

    The influence of coastal processes on inner shelf sediment distribution : the Eastern Algarve Shelf (Southern Portugal)

    Get PDF
    This study examines sediment distribution patterns in the Southeastern Algarve inner shelf (southern Portugal), an area characterized by marked variations in its coastal environment and low continental supply of sediments. The specific goals of this study were to identify the principal sediment sources and the factors influencing sediment transport paths and deposition. A total of 199 samples, collected along the shelf from the Guadiana River mouth to Olhos de Água, were analyzed. Grain-size distribution and parameters were measured for all the samples. Terrigenous and biogenic components of sand were identified in 38 samples, and results analyzed using multivariate non-linear multidimension scaling (MDS) and cluster analysis. Patterns of sediment distribution in this area of the inner shelf vary according to water depth and exhibit significant longshore variation, related mainly to coastal processes (littoral drift and storm currents) and to a lower degree to sediment sources. Sand is dominant at all depths, reflecting the influence of littoral drift in the supply and redistribution of shelf sediments. Fine and gravelsized deposits are significant in specific areas and are usually associated with changes in sediment composition. Five sectors have been identified according to sedimentary dynamics. The results, based on geostatistical and multivariate analysis, have allowed detailed sediment distribution maps to be generated, which represent an update of the existing cartography and serve as a tool for the management of coastal and marine resources. They have been furthermore compared with inner shelf sediment dynamics in other regions worldwide, to distinguish between specific regional responses to forcing mechanisms and processes that are more generalized within this type of shelf environments. In this context, the results obtained results in the Algarve study area are of great interest for the understanding of sediment dynamics of sand dominated inner shelves with reduced continental suppl

    Navigation Facility for High Accuracy Offline Trajectory and Attitude Estimation in Airborne Applications

    Get PDF
    The paper focuses on a navigation facility, relying on commercial-off-the-shelf (COTS) technology, developed to generate high-accuracy attitude and trajectory measurements in postprocessing. Target performance is cm-level positioning with tenth of degree attitude accuracy. The facility is based on the concept of GPS-aided inertial navigation but comprises carrier-phase differential GPS (CDGPS) processing and attitude estimation based on multiantenna GPS configurations. Expected applications of the system include: (a) performance assessment of integrated navigation systems, developed for general aviation aircraft and medium size unmanned aircraft systems (UAS); (b) generation of reference measurements to evaluate the flight performance of airborne sensors (e.g., radar or laser); and (c) generation of reference trajectory and attitude for improving imaging quality of airborne remote sensing data. The paper describes system architecture, selected algorithms for data processing and integration, and theoretical performance evaluation. Experimental results are also presented confirming the effectiveness of the implemented approach

    Decision-making framework for positive energy building design through key performance indicators relating geometry, localization, energy and PV system integration

    Get PDF
    The effectiveness of positive energy building (PEB) design largely depends on a balanced approach between building design and energy performance. The current common architectural process is lacking guidelines to address the impact of early design decisions in achieving the energy positive building goals. A selection of case study office buildings with an intended architectural diversity provide homogenized real data for this research. The aim is to find connections among four fields that are relevant for the PEB design process: building geometry, location, energy consumption and building integrated photovoltaics. The interrelations among them are synthesized in several novel key performance indicators (KPIs) that conclude, i.a., that only buildings with a roof-to-façade area ratio higher than 28% may achieve a 100% self-sufficiency. The PV area corresponding to 15% of the envelope is a necessary starting threshold to achieve a self-sufficient PEB. The installed power capacity of the PV system should be above 30 Wp/m2c. The main contribution is a decision-making framework that can be sequentially applied providing useful limits, thresholds and figures that guide towards effective architectural decisions for PV system integration in the early PEB design process

    Population overlap and habitat segregation in wintering Black-tailed Godwits Limosa limosa

    Get PDF
    Distinct breeding populations of migratory species may overlap both spatially and temporally, but differ in patterns of habitat use. This has important implications for population monitoring and conservation. To quantify the extent to which two distinct breeding populations of a migratory shorebird, the Black-tailed Godwit Limosa limosa, overlap spatially, temporally and in their use of different habitats during winter. We use mid-winter counts between 1990 and 2001 to identify the most important sites in Iberia for Black-tailed Godwits. Monthly surveys of estuarine mudflats and rice-fields at one major site, the Tejo estuary in Portugal in 2005-2007, together with detailed tracking of colour-ringed individuals, are used to explore patterns of habitat use and segregation of the Icelandic subspecies L. l. islandica and the nominate continental subspecies L. l. limosa. In the period 1990-2001, over 66 000 Black-tailed Godwits were counted on average in Iberia during mid-winter (January), of which 80% occurred at just four sites: Tejo and Sado lower basins in Portugal, and Coto Dontildeana and Ebro Delta in Spain. Icelandic Black-tailed Godwits are present throughout the winter and forage primarily in estuarine habitats. Continental Black-tailed Godwits are present from December to March and primarily use rice-fields. Iberia supports about 30% of the Icelandic population in winter and most of the continental population during spring passage. While the Icelandic population is currently increasing, the continental population is declining rapidly. Although the estuarine habitats used by Icelandic godwits are largely protected as Natura 2000 sites, the habitat segregation means that conservation actions for the decreasing numbers of continental godwits should focus on protection of rice-fields and re-establishment of freshwater wetlands

    Energy balance and photovoltaic integration in positive energy buildings. Design and performance in built office case studies

    Get PDF
    Solar design will be reshaping the architecture as one way to address the global climate crisis and the reduction of fossil fuel consumption. This paper analyses the current definition of Positive Energy Building (PEB) and a selection of both NZEB and PEB built projects with real monitored data, discussing their design features and potential for achieving positive energy balance. The research aims to assess an optimal ratio between PV area in both roof and façade, net floor building area and achieved self-sufficiency ratios in office buildings. The study shows that most of the buildings’ PV systems have an area equal to 10-20% of the total building’s net floor area. Buildings that have PV to area ratio from 13 to 20% are self-sufficient from 100 to 150%. PV installation in the façades results decisive for reaching positive energy balance. The relation of the PV system installed on the façade to PV system on the roof is from 50 to 57 % for the studied buildings. Buildings located in sites with higher GHI tend to have lower PV area ratios and a ratio of 20% or more is valid for all the studied sites to achieve electrical energy self-sufficiency

    Overview of Phosphorus Effect in Molybdenum-Based Hydrotreating Catalysts Supported on Ordered Mesoporous Siliceous Materials

    Get PDF
    This chapter presents an overview of the literature on the effect of phosphorus modification of ordered mesoporous silica (OMS) such as MCM-41, HMS, SBA-15, and SBA-16 to be used as supports for hydrotreating catalysts based on transition metal sulfides (TMS). The influence of the support modification with variable quantities of phosphorus on the performance for hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) reactions is outlined and discussed considering the changes in the structural and textural properties (SBET), acidity, reducibility, etc., of the substrate brought about by phosphorus incorporation

    Goat milk production and quality on Tanzania-grass pastures, with supplementation.

    Get PDF
    It was evaluated the production and quality of milk produced by goats grazing Panicum maximum Jacq cv. Tanzania (Guineagrass) and receiving four levels of concentrate supplementation. Eight Anglo Nubian goats, aged between two and four years, 43.6 kg in average body weight and between the 2nd and 4th lactation were distributed into two 4 x 4 balanced Latin square design. The supplementation levels were: 0.0, 0.5, 1.0 and 1.5% of body weight. The concentrate was composed of corn and soybean meal. The intake of dry matter and nutrients, and the daily production of milk, 4% fat-corrected milk, fat, protein, lactose and total solids had increased (p < 0.05) with supplementation, whereas fat and total solids percentage were reduced (p < 0.05). The concentrate supplementation up to 1.5% of live weight in Tanzania-grass pasture raises the intake of dry matter and nutrients, resulting in a linear increase in milk production and of its components. [Produção e qualidade do leite de cabras em pasto cultivado de capim-Tanzânia suplementadas com concentrado]. Resumo: Avaliou-se a produção e qualidade do leite de cabras em pasto cultivado de Panicum maximum Jacq cv. Tanzânia sob níveis de suplementação com concentrado. Foram utilizadas oito cabras da raça Anglonubiana, com idade entre dois e quatro anos, peso médio de 43,6 kg, entre a 2ª e 4ª ordem de lactação, distribuídas em duplo quadrado latino balanceado 4 x 4. Os níveis de suplementação avaliados foram: 0,0; 0,5; 1,0 e 1,5% do peso vivo. O concentrado, foi composto por grão de milho e farelo de soja. O consumo de matéria seca e de nutrientes e as produções diárias de leite, de leite corrigido a 4% de gordura, gordura, proteína, lactose e sólidos totais aumentaram com a suplementação, enquanto que os teores de gordura e sólidos totais reduziram. A suplementação com concentrado em até 1,5% do peso vivo em pasto cultivado de capim-tanzânia promove aumento no consumo de matéria seca e de nutrientes da dieta, do que resulta o aumento linear na produção de leite e de seus constituintes

    Evaluation antimicrobial and antiadhesive properties of the biosurfactant lunasan produced by candida sphaerica UCP 0995

    Get PDF
    Different groups of biosurfactants exhibit diverse properties and display a variety of physiological functions in producer microorganisms; these include enhancing the solubility of hydrophobic/water-insoluble compound, heave metal binding, bacterial pathogenesis, cell adhesion and aggregation, quorum sensing and biofilm formation. Candida sphaerica was grown in a low cost medium, consisting of distilled water supplemented with 9% refinery residue of soybean oil and 9% corn steep liquor, for 144 h at 28 C and 150 rpm. The cell-free supernatant obtained at the end of the experiments was submitted to extraction, and afterward the biosurfactant was isolated using methanol with a yield of 9 g l-1. The critical micelle concentration of the biosurfactant was found to be 0.25 mg ml-1 with a surface tension of 25 mN m-1. Several concentrations of the biosurfactant (0.625–10 mg ml-1) were used to evaluate its antimicrobial and antiadhesive activities against a variety of microorganisms. The biosurfactant showed antimicrobial activity against Streptococcus oralis (68%), Candida albicans (57%), and Staphylococcus epidermidis(57.6%) for the highest concentration tested. Furthermore, the biosurfactant at a concentration of 10 mg ml-1 inhibited the adhesion between 80 and 92% of Pseudomonas aeruginosa, Streptococcus agalactiae, Streptococcus sanguis12. Inhibition of adhesion with percentages near 100% occurred for the higher concentrations of biosurfactant used. Results gathered in this study point to a potential use of the biosurfactant in biomedical applicationsThe authors acknowledge the funding agencies FACEPE, CNPq, FINEP, PRONEX, and UNICAMP for using their facilities and CAPES for sandwich doctorate scholarship
    corecore