181 research outputs found
BN 52021 (a platelet activating factor-receptor antagonist) decreases alveolar macrophage-mediated lung injury in experimental extrinsic allergic alveolitis.
Several lines of research indirectly suggest that platelet activating factor (PAF) may intervene in the pathogenesis of extrinsic allergic alveolitis (EAA). The specific aim of our study was to evaluate the participation of PAF on macrophage activation during the acute phase of EAA in an experimental model of this disease developed in guinea pigs. Initially we measured the concentration of PAF in bronchoalvedar lavage fluid, blood and lung tissue. In a second phase we evaluate the participation of PAF on alveolar macrophage activation and parenchymal lung injury. The effect of PAF on parenchymal lung injury was evaluated by measuring several lung parenchymatous lesion indices (lung index, bronchoalvedar lavage fluid (BALF) lactic hydrogenase activity and BALF alkaline phosphatase activity) and parameters of systemic response to the challenge (acute phase reagents). We observed that induction of the experimental EAA gave rise to an increase in the concentration of PAF in blood and in lung tissue. The use of the PAF-receptor antagonist BN52021 decreases the release of lysosomal enzymes (beta-glucuronidase and tartrate-sensitive acid phosphatase) to the extracellular environment both in vivo and in vitro. Furthermore, antagonism of the PAF receptors notably decreases pulmonary parenchymatous lesion. These data suggest that lung lesions from acute EAA are partly mediated by local production of PAF
Role of lysosomal enzymes released by alveolar macrophages in the pathogenesis of the acute phase of hypersensitivity pneumonitis
Hydrolytic enzymes are the major constituents of alveolar macrophages (AM) and have been shown to be involved in many aspects of the inflammatory pulmonary response. The aim of this study was to evaluate the role of lysosomal enzymes in the acute phase of hypersensitivity pneumonitis (HPs). An experimental study on AM lysosomal enzymes of an HP-guinea-pig model was performed. The results obtained both in vivo and in vitro suggest that intracellular enzymatic activity decrease is, at least partly, due to release of lysosomal enzymes into the medium. A positive but slight correlation was found between extracellular lysosomal activity and four parameters of lung lesion (lung index, bronchoalveolar fluid total (BALF) protein concentration, BALF LDH and BALF alkaline phosphatase activities). All the above findings suggest that the AM release of lysosomal enzymes during HP is a factor involved, although possibly not the only one, in the pulmonary lesions appearing in this disease
Forage Yield and Nutritive Value of 30 Cultivars of Maize for Silage in the Highland Valleys of Central Mexico
In Mexico, the selection of maize cultivars for forage has mainly been based on dry matter (DM) yields, not considering nutritional quality as an important evaluation parameter. The objective of this study was to assess forage yield and nutritive value of Highland and Subtropical maize cultivars for silage in the Highland Valleys of Central MĂ©xico
Estimation of the vertical distribution of the fine canopy fuel in Pinus sylvestris stands using low density LiDAR data
[EN] Canopy fuel load, canopy bulk density and canopy base height are structural variables used to predict crown fire initiation and spread. Direct measurement of these variables is not functional, and they are usually estimated indirectly by modelling. Advances in fire behaviour modelling require accurate and landscape scale estimates of the complete vertical distribution of canopy fuels. The goal of the present study is to model the vertical profile of available canopy fuels in Scots pine stands by using data from the Spanish national forest inventory and low-density LiDAR data (0.5 first returns mâ2) provided by Spanish PNOA project (Plan Nacional de OrtofotografĂa AĂ©rea). In a first step, the vertical distribution of the canopy fuel load was modelled using the Weibull probability density function. In a second step, a system of models was fitted to relate the canopy variables to Lidar-derived metrics. Models were fitted simultaneously to compensate the effects of the inherent cross-model correlation between errors. Heteroscedasticity was also analyzed, but correction in the fitting process was not necessary. The estimated canopy fuel load profiles from LiDAR-derived metrics explained 41% of the variation in canopy fuel load in the analysed plots. The proposed models can be used to assess the effectiveness of different forest management alternatives for reducing crown fire hazard.[ES] La altura de la base de la copa, la carga de combustible disponible y la densidad aparente son caracterĂsticas estructurales del dosel de copas utilizadas para predecir la actividad de fuego de copas. La mediciĂłn directa en campo de estas variables es imprĂĄctica y por tanto sus valores se estiman habitualmente mediante el empleo de modelos predictivos. Avances en la modelizaciĂłn del comportamiento del fuego hacen que sea de gran interĂ©s explorar la posibilidad de estimar de forma precisa y a escala de paisaje la distribuciĂłn vertical de los combustibles en el dosel de copas. En este sentido, este estudio pretende analizar el potencial de los datos obtenidos de sensores LiDAR (Light Detection and Ranging) aerotransportados para modelizar dicha distribuciĂłn vertical en masas de pino silvestre en Galicia. Para ello se usaron datos del vuelo LiDAR del PNOA (Plan Nacional de OrtofotografĂa AĂ©rea) con una densidad de 0,5 primeros retornos mâ2 y datos de campo procedentes del Cuarto Inventario Forestal Nacional (IFN4). En un primer paso, la distribuciĂłn vertical fue caracterizada empleando la funciĂłn de densidad de probabilidad de Weibull para, en un segundo paso, ajustar un sistema de ecuaciones que relacionan las variables del dosel con mĂ©tricas derivadas de los datos LiDAR. Las ecuaciones se ajustaron simultĂĄneamente para corregir los posibles problemas de correlaciĂłn entre errores. Las distribuciones verticales finalmente estimadas explicaron el 41% de la variabilidad observada en las parcelas de estudio. El sistema de ecuaciones propuesto puede ser usado tambiĂ©n para evaluar la efectividad de diferentes alternativas de gestiĂłn del combustible para reducir el riesgo de fuego de copa en rodales de pino silvestre.Fidalgo-GonzĂĄlez, LA.; Arellano-PĂ©rez, S.; Ălvarez-GonzĂĄlez, JG.; Castedo-Dorado, F.; Ruiz-GonzĂĄlez, AD.; GonzĂĄlez-Ferreiro, E. (2019). EstimaciĂłn de la distribuciĂłn vertical de combustibles finos del dosel de copas en masas de Pinus sylvestris empleando datos LiDAR de baja densidad. Revista de TeledetecciĂłn. (53):1-16. https://doi.org/10.4995/raet.2019.11241SWORD1165
The JWST EXCELS survey: too much, too young, too fast? Ultra-massive quiescent galaxies at 3 < z < 5
Funding: ACC thanks the Leverhulme Trust for their support via a Leverhulme Early Career Fellowship. ACC acknowledges support from a UKRI Frontier Research Guarantee Grant [grant reference EP/Y037065/1]. RB, CD, DJM, RJM, and JSD acknowledge the support of the Science and Technology Facilities Council. FC, KZA-C, and TS acknowledge support from a UKRI Frontier Research Guarantee Grant [grant reference EP/X021025/1]. JSD also acknowledges the support of the Royal Society through a Royal Society Research Professorship. PS acknowledges INAF Mini Grant 2022 âThe evolution of passive galaxies through cosmic timeâ.We report ultra-deep, medium-resolution spectroscopic observations for four quiescent galaxies with log10(M*/Mâ) >  11 at 3 < z < 5. These data were obtained with JWST NIRSpec as part of the Early eXtragalactic Continuum and Emission Line Science (EXCELS) survey, which we introduce in this work. The first two galaxies are newly selected from PRIMER UDS imaging, both at z = 4.62 and separated by 860 pkpc on the sky, within a larger structure for which we confirm several other members. Both formed at z â 8 - 10. These systems could plausibly merge by the present day to produce a local massive elliptical galaxy. The other two ultra-massive quiescent galaxies are previously known at z = 3.99 and 3.19, with the latter (ZF-UDS-7329) having been the subject of debate as potentially too old and too massive to be accommodated by the Î-CDM halo-mass function. Both exhibit high stellar metallicities, and for ZF-UDS-7329 we are able to measure the α-enhancement, obtaining [Mg/Fe] = 0.42+0.19-0.17. We finally evaluate whether these four galaxies are consistent with the Î-CDM halo-mass function using an extreme value statistics approach. We find that the z = 4.62 objects and the z = 3.19 object are unlikely within our area under the assumption of standard stellar fractions (f* â 0.1-0.2). However, these objects roughly align with the most massive galaxies expected under the assumption of 100 per cent conversion of baryons to stars (f*= 1). Our results suggest extreme galaxy formation physics during the first billion years, but no conflict with Î-CDM cosmology.Peer reviewe
NIBBS-Search for Fast and Accurate Prediction of Phenotype-Biased Metabolic Systems
Understanding of genotype-phenotype associations is important not only for furthering our knowledge on internal cellular processes, but also essential for providing the foundation necessary for genetic engineering of microorganisms for industrial use (e.g., production of bioenergy or biofuels). However, genotype-phenotype associations alone do not provide enough information to alter an organism's genome to either suppress or exhibit a phenotype. It is important to look at the phenotype-related genes in the context of the genome-scale network to understand how the genes interact with other genes in the organism. Identification of metabolic subsystems involved in the expression of the phenotype is one way of placing the phenotype-related genes in the context of the entire network. A metabolic system refers to a metabolic network subgraph; nodes are compounds and edges labels are the enzymes that catalyze the reaction. The metabolic subsystem could be part of a single metabolic pathway or span parts of multiple pathways. Arguably, comparative genome-scale metabolic network analysis is a promising strategy to identify these phenotype-related metabolic subsystems. Network Instance-Based Biased Subgraph Search (NIBBS) is a graph-theoretic method for genome-scale metabolic network comparative analysis that can identify metabolic systems that are statistically biased toward phenotype-expressing organismal networks. We set up experiments with target phenotypes like hydrogen production, TCA expression, and acid-tolerance. We show via extensive literature search that some of the resulting metabolic subsystems are indeed phenotype-related and formulate hypotheses for other systems in terms of their role in phenotype expression. NIBBS is also orders of magnitude faster than MULE, one of the most efficient maximal frequent subgraph mining algorithms that could be adjusted for this problem. Also, the set of phenotype-biased metabolic systems output by NIBBS comes very close to the set of phenotype-biased subgraphs output by an exact maximally-biased subgraph enumeration algorithm ( MBS-Enum ). The code (NIBBS and the module to visualize the identified subsystems) is available at http://freescience.org/cs/NIBBS
2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Actualización del Documento Sevilla
La transfusiĂłn de sangre alogĂ©nica (TSA) no es inocua, y como consecuencia han surgido mĂșltiples alternativas a la misma (ATSA). Existe variabilidad respecto a las indicaciones y buen uso de las ATSA. Dependiendo de la especialidad de los mĂ©dicos que tratan a los pacientes, el grado de anemia, la polĂtica transfusional, la disponibilidad de las ATSA y el criterio personal, estas se usan de forma variable. Puesto que las ATSA tampoco son inocuas y pueden no cumplir criterios de coste-efectividad, la variabilidad en su uso es inaceptable. Las sociedades españolas de AnestesiologĂa y ReanimaciĂłn (SEDAR), HematologĂa y Hemoterapia (SEHH), Farmacia Hospitalaria (SEFH), Medicina Intensiva y Unidades Coronarias (SEMICYUC), Trombosis y Hemostasia (SETH) y Transfusiones SanguĂneas (SETS) han elaborado un documento de consenso para el buen uso de la ATSA. Un panel de expertos de las 6 sociedades ha llevado a cabo una revisiĂłn sistemĂĄtica de la literatura mĂ©dica y elaborado el 2013. Documento Sevilla de Consenso sobre Alternativas a la TransfusiĂłn de Sangre AlogĂ©nica. Solo se contempla las ATSA dirigidas a disminuir la transfusiĂłn de concentrado de hematĂes. Se definen las ATSA como toda medida farmacolĂłgica y no farmacolĂłgica encaminada a disminuir la transfusiĂłn de concentrado de hematĂes, preservando siempre la seguridad del paciente. La cuestiĂłn principal que se plantea en cada Ătem se formula, en forma positiva o negativa, como: «La ATSA en cuestiĂłn reduce/no reduce la tasa transfusional». Para formular el grado de recomendaciĂłn se ha usado la metodologĂa Grades of Recommendation Assessment, Development and Evaluation (GRADE)
Isotemporal substitution of inactive time with physical activity and time in bed: Cross-sectional associations with cardiometabolic health in the PREDIMED-Plus study
© 2019 The Author(s). Background: This study explored the association between inactive time and measures of adiposity, clinical parameters, obesity, type 2 diabetes and metabolic syndrome components. It further examined the impact of reallocating inactive time to time in bed, light physical activity (LPA) or moderate-To-vigorous physical activity (MVPA) on cardio-metabolic risk factors, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults. Methods: This is a cross-sectional analysis of baseline data from 2189 Caucasian men and women (age 55-75 years, BMI 27-40 Kg/m2) from the PREDIMED-Plus study (http://www.predimedplus.com/). All participants had â„3 components of the metabolic syndrome. Inactive time, physical activity and time in bed were objectively determined using triaxial accelerometers GENEActiv during 7 days (ActivInsights Ltd., Kimbolton, United Kingdom). Multiple adjusted linear and logistic regression models were used. Isotemporal substitution regression modelling was performed to assess the relationship of replacing the amount of time spent in one activity for another, on each outcome, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults. Results: Inactive time was associated with indicators of obesity and the metabolic syndrome. Reallocating 30 min per day of inactive time to 30 min per day of time in bed was associated with lower BMI, waist circumference and glycated hemoglobin (HbA1c) (all p-values < 0.05). Reallocating 30 min per day of inactive time with 30 min per day of LPA or MVPA was associated with lower BMI, waist circumference, total fat, visceral adipose tissue, HbA1c, glucose, triglycerides, and higher body muscle mass and HDL cholesterol (all p-values < 0.05). Conclusions: Inactive time was associated with a poor cardio-metabolic profile. Isotemporal substitution of inactive time with MVPA and LPA or time in bed could have beneficial impact on cardio-metabolic health. Trial registration: The trial was registered at the International Standard Randomized Controlled Trial (ISRCTN: http://www.isrctn.com/ISRCTN89898870) with number 89898870 and registration date of 24 July 2014, retrospectively registered
Isotemporal substitution of inactive time with physical activity and time in bed: cross-sectional associations with cardiometabolic health in the PREDIMEDPlus study
Background: This study explored the association between inactive time and measures of adiposity, clinical parameters, obesity, type 2 diabetes and metabolic syndrome components. It further examined the impact of reallocating inactive time to time in bed, light physical activity (LPA) or moderate-to-vigorous physical activity (MVPA) on cardio-metabolic risk factors, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults.
Methods: This is a cross-sectional analysis of baseline data from 2189 Caucasian men and women (age 55-75 years, BMI 27-40 Kg/m2) from the PREDIMED-Plus study (http://www.predimedplus.com/). All participants had â„3 components of the metabolic syndrome. Inactive time, physical activity and time in bed were objectively determined using triaxial accelerometers GENEActiv during 7 days (ActivInsights Ltd., Kimbolton, United Kingdom). Multiple adjusted linear and logistic regression models were used. Isotemporal substitution regression modelling was performed to assess the relationship of replacing the amount of time spent in one activity for another, on each outcome, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults.
Results: Inactive time was associated with indicators of obesity and the metabolic syndrome. Reallocating 30 min per day of inactive time to 30 min per day of time in bed was associated with lower BMI, waist circumference and glycated hemoglobin (HbA1c) (all p-values < 0.05). Reallocating 30 min per day of inactive time with 30 min per day of LPA or MVPA was associated with lower BMI, waist circumference, total fat, visceral adipose tissue, HbA1c, glucose, triglycerides, and higher body muscle mass and HDL cholesterol (all p-values < 0.05).
Conclusions: Inactive time was associated with a poor cardio-metabolic profile. Isotemporal substitution of inactive time with MVPA and LPA or time in bed could have beneficial impact on cardio-metabolic health
An increase of cereal intake as an approach to weight reduction in children is effective only when accompanied by nutrition education: a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>The main emphasis of dietary advice for control of obesity has been on reducing dietary fat. Increasing ready to eat cereal (RTEC) consumption could be a strategy to reduce fat intake and increase carbohydrate intake resulting in a diet with lower energy density.</p> <p>Objectives</p> <p>1. To determine if an increase in RTEC intake is an effective strategy to reduce excess body weight and blood lipids in overweight or at risk of overweight children. 2. To determine if a nutrition education program would make a difference on the response to an increase in cereal intake. 3) To determine if increase in RTEC intake alone or with a nutrition education program has an effect on plasma lipid profile.</p> <p>Experimental design</p> <p>One hundred and forty seven overweight or at risk of overweight children (6â12 y of age) were assigned to one of four different treatments: a. One serving of 33 ± 7 g of RTEC for breakfast; b. one serving of 33 ± 7 g of RTEC for breakfast and another one for dinner; c. one serving of 33 ± 7 g of RTEC for breakfast and a nutrition education program. d. Non intervention, control group. Anthropometry, body composition, physical activity and blood lipids were measured at baseline, before treatments, and 12 weeks after treatments.</p> <p>Results</p> <p>After 12 weeks of intervention only the children that received 33 ± 7 g of RTEC and nutrition education had significantly lower body weight [-1.01 (-1.69, -0.34) ], p < 0.01], lower BMI [-0.95 (-1.71, -0.20), p < 0.01] and lower total body fat [-0.71 (-1.71, 0.28), p < 0.05] compared with the control group [1.19 (0.39, 1.98), 0.01 (-0.38, 0.41), 0.44 (-0.46, 1.35) respectively]. Plasma triglycerides and VLDL were significantly reduced [-20.74 (-36.44, -5.05), -3.78 (-6.91, -0.64) respectively, p < 0.05] and HDL increased significantly [6.61 (2.15, 11.08), p < 0.01] only in this treatment group. The groups that received 1 or 2 doses of RTEC alone were not significantly different to the control group.</p> <p>Conclusion</p> <p>A strategy to increase RTEC consumption, as a source of carbohydrate, to reduce obesity is effective only when accompanied by nutrition education. The need for education could be extrapolated to other strategies intended for treatment of obesity.</p> <p>Trial Registration</p> <p>Australian New Zealand Clincial Trial Registry. Request no: ACTRN12608000025336</p
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