985 resultados para Differential Responses


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Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3 fb−1 of pp collisions produced by the Large Hadron Collider at a center-of-mass energy of s√=8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured H→γγ and H→ZZ∗→4ℓ event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σpp→H=33.0±5.3(stat)±1.6(sys)pb. The measurements are compared to state-of-the-art predictions.

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Gold nanoparticles were dispersed in two different dielectric matrices, TiO2 and Al2O3, using magnetron sputtering and a post-deposition annealing treatment. The main goal of the present work was to study how the two different host dielectric matrices, and the resulting microstructure evolution (including both the nanoparticles and the host matrix itself) promoted by thermal annealing, influenced the physical properties of the films. In particular, the structure and morphology of the nanocomposites were correlated with the optical response of the thin films, namely their localized surface plasmon resonance (LSPR) characteristics. Furthermore, and in order to scan the future application of the two thin film system in different types of sensors (namely biological ones), their functional behaviour (hardness and Young's modulus change) was also evaluated. Despite the similar Au concentrations in both matrices (~ 11 at.%), very different microstructural features were observed, which were found to depend strongly on the annealing temperature. The main structural differences included: (i) the early crystallization of the TiO2 host matrix, while the Al2O3 one remained amorphous up to 800 °C; (ii) different grain size evolution behaviours with the annealing temperature, namely an almost linear increase for the Au:TiO2 system (from 3 to 11 nm), and the approximately constant values observed in the Au:Al2O3 system (4–5 nm). The results from the nanoparticle size distributions were also found to be quite sensitive to the surrounding matrix, suggesting different mechanisms for the nanoparticle growth (particle migration and coalescence dominating in TiO2 and Ostwald ripening in Al2O3). These different clustering behaviours induced different transmittance-LSPR responses and a good mechanical stability, which opens the possibility for future use of these nanocomposite thin film systems in some envisaged applications (e.g. LSPR-biosensors).

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Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a marked decline in cognition and memory function. Increasing evidence highlights the essential role of neuroinflammatory and immune-related molecules, including those produced at the brain barriers, on brain immune surveillance, cellular dysfunction and amyloid beta (Aß) pathology in AD. Therefore, understanding the response at the brain barriers may unravel novel pathways of relevance for the pathophysiology of AD. Herein, we focused on the study of the choroid plexus (CP), which constitutes the blood-cerebrospinal fluid barrier, in aging and in AD. Specifically, we used the PDGFB-APPSwInd (J20) transgenic mouse model of AD, which presents early memory decline and progressive Aß accumulation, and littermate age-matched wild-type (WT) mice, to characterize the CP transcriptome at 3, 5-6 and 11-12months of age. The most striking observation was that the CP of J20 mice displayed an overall overexpression of type I interferon (IFN) response genes at all ages. Moreover, J20 mice presented a high expression of type II IFN genes in the CP at 3months, which became lower than WT at 5-6 and 11-12months. Importantly, along with a marked memory impairment and increased glial activation, J20 mice also presented a similar overexpression of type I IFN genes in the dorsal hippocampus at 3months. Altogether, these findings provide new insights on a possible interplay between type I and II IFN responses in AD and point to IFNs as targets for modulation in cognitive decline.

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Exposure to chronic stress can have broad effects on health ranging from increased predisposition for neuropsychiatric disorders to deregulation of immune responses. The chronic unpredictable stress (CUS) protocol has been widely used to study the impact of stress exposure in several animal models and consists in the random, intermittent, and unpredictable exposure to a variety of stressors during several weeks. CUS has consistently been shown to induce behavioral and immunological alterations typical of the chronic stress-response. Unfortunately C57BL/6 mice, one of the most widely used mouse strains, due to the great variety of genetically modified lines, seem to be resistant to the commonly used 4-week-long CUS protocol. The definition of an alternative CUS protocol allowing the use of C57BL/6 mice in chronic stress experiments is a need. Here, we show that by extending the CUS protocol to 8?weeks is possible to induce a chronic stress-response in C57BL/6 mice, as revealed by abrogated body weight gain, increased adrenals weight, and an overactive hypothalamic-pituitary-adrenal axis with increased levels of serum corticosterone. Moreover, we also observed stress-associated behavioral alterations, including the potentiation of anxious-like and depressive-like behaviors and a reduction of exploratory behavior, as well as subtle stress-related changes in the cell population of the thymus and of the spleen. The present protocol for C57BL/6 mice consistently triggers the spectrum of CUS-induced changes observed in rats and, thus, will be highly useful to researchers that need to use this particular mouse strain as an animal model of neuropsychiatric disorders and/or immune deregulation related to CUS.

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Long-term exposure to transmeridian flights has been shown to impact cognitive functioning. Nevertheless, the immediate effects of jet lag in the activation of specific brain networks have not been investigated. We analyzed the impact of short-term jet lag on the activation of the default mode network (DMN). A group of individuals who were on a transmeridian flight and a control group went through a functional magnetic resonance imaging acquisition. Statistical analysis was performed to test for differences in the DMN activation between groups. Participants from the jet lag group presented decreased activation in the anterior nodes of the DMN, specifically in bilateral medial prefrontal and anterior cingulate cortex. No areas of increased activation were observed for the jet lag group. These results may be suggestive of a negative impact of jet lag on important cognitive functions such as introspection, emotional regulation and decision making in a few days after individuals arrive at their destination.

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ABSTRACTIn fish farmings, diseases can be reduced by using immunostimulants. The aim of this study was to evaluate the immunostimulant potential of Mentha piperita in tambaqui fed with 0, 0.5, 1.0 and 1.5% of oil per kg of commercial fish feed. The fish were inoculated with Aeromonas hydrophila to challenge them. Hematological and biochemical parameters were determined after 30 days of feeding and seven days after the challenge. There was no mortality and M. piperita oil did not influence fish production parameters. However, blood hemoglobin concentration (Hb) increased in the fish fed with 0.5 and 1.5% of oil per kg of diet; albumin increased in those fed with 1.0%; cholesterol increased in all groups with oil; and triglycerides increased in those fed with 0.5%. After the bacterial challenge, the fish showed decreases in Hb when fed with diet enriched with 1.5% oil per kg of diet, in mean corpuscular volume with 1.0% and in mean corpuscular hemoglobin concentration with 0 and 1.5%. Protein levels increased in groups with 0 and 1.5% of oil and albumin when fed with 0 and 1.0%; cholesterol levels increased in the control group; and high levels of triglycerides were observed in the groups with 0, 0.5 and 1.5%. Thus, M. piperita essential oil promoted hematological alterations in tambaqui and can be recommended in diets containing up to 1.0% per kg, because of the minimal physiological modifications caused. However, additional studies are necessary to obtain more information regarding to the physiological effects of this immunostimulant.

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Dissertação de mestrado em Plant Molecular Biology, Biotechnology and Bioentrepreneurship

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Measurements of differential cross sections for J/ψ production in p+Pb collisions at sNN−−−−√=5.02 TeV at the CERN Large Hadron Collider with the ATLAS detector are presented. The data set used corresponds to an integrated luminosity of 28.1 nb−1. The J/ψ mesons are reconstructed in the dimuon decay channel over the transverse momentum range 8differential cross section for production of nonprompt J/ψ is compared to a FONLL calculation that does not include nuclear effects. Forward-backward production ratios are presented and compared to theoretical predictions. These results complement previously published results by covering a region of higher transverse momentum and more central rapidity. They thus constrain the kinematic dependence of nuclear modifications of charmonium and b-quark production in p+Pb collisions.

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Noble metal powders containing gold and silver have been used for many centuries, providing different colours in the windows of the medieval cathedrals and in ancient Roman glasses. Nowadays, the interest in nanocomposite materials containing noble nanoparticles embedded in dielectric matrices is related with their potential use for a wide range of advanced technological applications. They have been proposed for environmental and biological sensing, tailoring colour of functional coatings, or for surface enhanced Raman spectroscopy. Most of these applications rely on the so-called localised surface plasmon resonance absorption, which is governed by the type of the noble metal nanoparticles, their distribution, size and shape and as well as of the dielectric characteristics of the host matrix. The aim of this work is to study the influence of the composition and thermal annealing on the morphological and structural changes of thin films composed of Ag metal clusters embedded in a dielectric TiO2 matrix. Since changes in size, shape and distribution of the clusters are fundamental parameters for tailoring the properties of plasmonic materials, a set of films with different Ag concentrations was prepared. The optical properties and the thermal behaviour of the films were correlated with the structural and morphological changes promoted by annealing. The films were deposited by DC magnetron sputtering and in order to promote the clustering of the Ag nanoparticles the as-deposited samples were subjected to an in-air annealing protocol. It was demonstrated that the clustering of metallic Ag affects the optical response spectrum and the thermal behaviour of the films.

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We report the case of an 8-month-old female infant with Uhl's anomaly, who underwent successful cardiac transplantation. The clinical findings, complementary laboratory tests, anatomic findings, and differential diagnosis of the anomaly are discussed.

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OBJECTIVE: We determined the effects of losartan and PD 123319 (antagonists of the AT1 and AT2 angiotensin receptors, respectively), and [Sar¹, Ala8] ANG II (a relatively peptide antagonist of angiotensin receptors) injected into the paraventricular nucleus (PVN) on water and 3% NaCl intake, and the diuretic, natriuretic, and pressor effects induced by administration of angiotensin II (ANG II) into the medial septal area (MSA) of conscious rats. METHODS: Holtzman rats were used . Animals were anesthetized with tribromoethanol (20 mg) per 100 grams of body weight, ip. A stainless steel guide cannula was implanted into the MSA and PVN. All drugs were injected in 0.5-mul volumes for 10-15 seconds. Seven days after brain surgery, water and 3% NaCl intake, urine and sodium excretion, and arterial blood pressure were measured. RESULTS: Losartan (40 nmol) and [Sar¹, Ala8] ANG II (40 nmol) completely eliminated whereas PD 123319 (40 nmol) partially blocked the increase in water and sodium intake and the increase in arterial blood pressure induced by ANG II (10 nmol) injected into the MSA. The PVN administration of PD 123319 and [Sar¹, Ala8] ANG II blocked whereas losartan attenuated the diuresis and natriuresis induced by MSA administration of ANG II. CONCLUSION: MSA involvement with PVN on water and sodium homeostasis and arterial pressure modulation utilizing ANGII receptors is suggested.

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OBJECTIVE: To differentiate the nature of functional cardiorespiratory limitations during exercise in individuals with chronic obstructive pulmonary disease (COPD) or congestive heart failure (CHF) and to determine indicators that may help their classifications. METHODS: The study comprised 40 patients: 23 with COPD and 17 with CHF. All individuals underwent maximal cardiopulmonary exercise testing on a treadmill. RESULTS: The values of peak gas exchange ratio (R peak), peak carbon dioxide production (VCO2 peak), and peak oxygen ventilatory equivalent (V E O2 peak) were higher in the patients with CHF than in those with COPD, and, therefore, those were the variables that characterized the differences between the groups. For group classification, the differentiating functions with the R peak, VCO2 peak (L/min), and V E O2 peak variables were used as follows: group COPD: - 44.886 + 78.832 x R peak + 5.442 x VCO2 peak + 0.336 x V E O2 peak; group CHF: - 69.251 + 89.740 x R peak + 8.461 x VCO2 peak + 0.574 x V E O2 peak. The differentiating function, whose result is greater, correctly classifies the patient's group as 90%. CONCLUSION: The R peak, VCO2 peak, and V E O2 peak values may be used to identify the cause of the functional cardiorespiratory limitations in patients with COPD and CHF.

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Antecedentes: En nuestro laboratorio hemos demostrado que antígenos (Ags) de Fasciola hepatica inducen en células dendríticas murinas (CD), diferentes propiedades tolerogénicas como la incapacidad por si mismos de inducir la maduración de las células, la resistencia a la maduración por ligandos de TLR, el incremento en la producción de IDO y también la capacidad de esta estas células de dirigir la respuesta inmune hacia un perfil Th2 y T reg. Por otra parte ha sido bien documentado que CD con características tolerogénicas, ya sea inmaduras o semimaduras, son útiles para reducir respuestas inflamatorias excesivas tales como las que ocurren en enfermedades autoinmunes. Además hemos demostrado que CD tratadas con Ags del parásito en conjunto con un ligando Toll (CpG-ODN) producen altos niveles de citoquinas anti-inflamatorias (IL-10 y TGF-) bajos de citoquinas proinflamatorias (TNF, IL-6, IL-12). Hipótesis: El fenotipo semimaduro alcanzado en las CDpodría ser utilizado para reducir la inflamación en un modelo de enfermedad autoinmune en donde existe una exacerbada respuesta Th1 y Th17, ya que la producción elevada de IL-10 y TGF- podría inhibir o controlar estas respuestas de manera directa o a través de la inducción de células T regulatorias. Objetivos: En este proyecto nosotros proponemos la inmunización de animales susceptibles (ratones DBA1/j), al desarrollo de artritis inducida por colágeno (AIC) con CD tratadas con Ags de F. hepatica en conjunto con CpG-ODN para reducir los síntomas clínicos de la enfermedad. Materiales a utilizar: En nuestro laboratorio hemos desarrollado un modelo de artritis inducida por colágeno (AIC) mediante dos inmunizaciones de ratones DBA1/j con colágeno tipo II bovino y adyuvante de Freund. El modelo permitió establecer un índice clínico mediante la hinchazón en las patas de los animales. Doce días posteriores a la primera inmunización los animales serán inyectados con CD tratadas con: 1. PBS, 2.Extracto total de F.hepatica (TE) + CII, 3. CpG + CII, 4. TE+CpG+CII Se realizará la observación macroscópica diaria, a partir de los 7 días de la 2a inmunización Luego del sacrificio las articulaciones de las patas se prepararán para realizar un análisis histológico. Se detectará en suero los niveles de anticuerpos IgG1 (perfil Th2) y de IgG2a (perfil Th1) mediante la técnica de ELISA. Se detectará también el perfil de citoquinas en los nódulos drenantes por la técnica de ELISA y adicionalmente la poblaciónes celulares de células T regulatorias (Treg) CD4+CD25+Foxp3 o células Tr1. Resultados esperados: Pensamos que el tratamiento de los animales que desarrollan AIC con CD semimaduras (por el tratamiento con TE y CpG), serán capaces de migrar a los órganos linfaticos y secretar TGF-be(inductora de células T reg), IL-10 (inductoras de células Tr1), IDO inhibitoria de la respuesta de Li T y promotor de células T reg, también podría generarse una respuesta Th2 (por la presencia de antígenos del parásito), y estas respuestas aisladas o en forma sinérgica podrían inhibir las respuestas de tipo Th17 y Th1 asociadas a la patología en esta enfermedad. Importancia del proyecto: En el desarrollo de la artritis existe un aumento de la inmunidad mediada por células, asi como de la respuesta inmune humoral hacia componentes de la matriz del cartílago. El tratamiento convencional de la artritis recae en general en el uso de inmunosupresores no-específicos, los cuales poseen una variedad de efectos adversos y la inhibición de la respuesta inflamatoria no es específica. En este proyecto proponemos el uso de CD tratadas con antígenos del helminto F. hepatica y CpG ligando Tol que capacita a estas células para generar una respuesta adaptativa de tipo regulatoria, útil en la inhibición de las respuestas inflamatorias como la que ocurre durante la progresión de artritis reumatoidea en un modelo experimental en ratones. We have shown that F. hepatica Ags-treated dendritic cells (DC) together with a TLRl ligand (CpG-ODN) produce high levels of anti-inflammatory cytokines (IL-10 and TGF-Beta) and low of proinflammatory cytokines (TNF, IL-6, IL -12). Hypothesis: The semimature phenotype achieved by DC, could be used to reduce inflammation in a model of autoimmune disease. The high production of IL-10 and TGF-Beta by these cells could directly or through the induction of T reg cells inhibit the inflammatory response. Objective: In this project we propose the immunization of DBA1 / j mice, susceptible to the development of collagen-induced arthritis (CIA) with F. hepatica-treated DC in conjunction with CpG-ODN to reduce clinical signs of disease. Materials: In our laboratory, we developed the CIA model by two immunizations of DBA1 / j mice with bovine type II collagen and Freund's adjuvant. The model allowed to stablish a clinical index by swelling in the legs of animals. Twelve days after the first immunization the animals are injected with DC treated with: 1. PBS 2. F.hepatica Extract (TE) + CII, 3. CpG + CII, 4. TE + CpG + CII Macroscopic observation will take place daily from 7 days of the 2nd immunization. After sacrifice the joints of the legs will be prepared for histological analysis. Serum levels of IgG1 antibodies (Th2 profile) and IgG2a (Th1 profile) will be detected by ELISA. It will also detected the cytokine profile in draining lymph nodes by ELISA and additionally the cell populations of regulatory T cells (Treg) CD4 + CD25 + Foxp3 or Tr1 cells. Expected results: We believe that the treatment of animals that had developed CIA with DC will be able to migrate to lymphatic organs and secrete TGF-B (T reg cell-inducing), IL-10 (inducing Tr1 cells), IDO (inhibitory of T cells and inducing of T reg cells) could alone or in synergy inhibit Th17-type responses and Th1 associated with the pathology in this disease.