82 research outputs found
Assessment of the suitability of chitosan/polybutylene succinate scaffolds seeded with mouse mesenchymal progenitor cells for a cartilage tissue engineering approach
In this work, scaffolds derived from a new biomaterial originated from the combination of a natural
material and a synthetic material were tested for assessing their suitability for cartilage tissue engineering
applications. In order to obtain a better outcome result in terms of scaffolds’ overall properties,
different blends of natural and synthetic materials were created. Chitosan and polybutylene succinate (CPBS)
50/50 (wt%) were melt blended using a twin-screw extruder and processed into 5 5 5mm scaffolds
by compression moulding with salt leaching. Micro-computed tomography analysis calculated an
average of 66.29% porosity and 92.78% interconnectivity degree for the presented scaffolds. The salt
particles used ranged in size between 63 and 125 lm, retrieving an average pore size of 251.28 lm.
Regarding the mechanical properties, the compressive modulus was of 1.73 ± 0.4MPa (Esec 1%). Cytotoxicity
evaluation revealed that the leachables released by the developed porous structures were not
harmful to the cells and hence were noncytotoxic. Direct contact assays were carried out using a mouse
bone marrow–derived mesenchymal progenitor cell line (BMC9). Cells were seeded at a density of 5 105
cells/scaffold and allowed to grow for periods up to 3 weeks under chondrogenic differentiating conditions.
Scanning electron microscopy analysis revealed that the cells were able to proliferate and colonize
the scaffold structure, and MTS test demonstrated cell viability during the time of the experiment.
Finally, Western blot performed for collagen type II, a natural cartilage extracellular matrix component,
showed that this protein was being expressed by the end of 3 weeks, which seems to indicate that the
BMC9 cells were being differentiated toward the chondrogenic pathway. These results indicate the
adequacy of these newly developed C-PBS scaffolds for supporting cell growth and differentiation toward
the chondrogenic pathway, suggesting that they should be considered for further studies in the cartilage
tissue engineering field.J. T. Oliveira would like to acknowledge the grant (SFRH/ BD17135/2004) from Portuguese Foundation for Science and Technology (FCT). The authors would like to thank Fernanda Marques, at the Institute for Health and Life Sciences (ICVS), University of Minho, Braga, Portugal, for her help with the Western blot analysis, as well as the staff at ICVS for allowing to use their facilities. The monoclonal antibody for collagen type II was obtained from the Developmental Studies Hybridoma Bank developed under the auspices of the NICHD and maintained by the Department of Biological Sciences, University of Iowa (Iowa City, IA). This work was carried out under the scope of the European NoE EXPERTISSUES (NMP3-CT-2004-500283), and partially supported by the European Project GENOSTEM (LSHB-CT-2003-503161) and the FCT Project CartiScaff (POCTI/SAU-BMA/58991/2004)
Water sediment physicochemical dynamics in a large reservoir in the Mediterranean region under multiple stressors
Nowadays, the Mediterranean freshwater systems face the threat of water scarcity, along with other multiple stressors (e.g. organic and inorganic contamination, geomorphological
alterations, invasive species), leading to the impairment of their ecosystem services. All these stressors have been speeding up, due to climate variability and land cover/ land use changes, turning them into a big challenge for the water management plans. The present study analyses
the physicochemical and phytoplankton biomass (chlorophyll-a) dynamics of a large
reservoir, in the Mediterranean region (Alqueva reservoir, Southern Portugal), under diverse
meteorological conditions and land cover/land use real scenarios (2017 and 2018). The most
important stressors were identified and the necessary tools and information for a more
effective management plan were provided. Changes in these parameters were further related to the observed variations in the meteorological conditions and in the land cover/land use. The increase of nutrients and ions in the water column were more obvious in periods of severe drought. Further, the enhancement of nutrients concentrations, potentially caused by the intensification of agricultural activities, may indicate an increased risk of water eutrophication (see Figure 1).
The results provide information to the decision-makers, to build strategies on how to avoid a higher deterioration of the water quality in the Alqueva reservoir, induced by interacting and synergistic effects of climate change and LULC management. It is essential to promote the sustainability of LULC, with the control of agriculture areas in the basin and the implementation of sustainable environmental management practices. In fact, the adaptation
solutions based on LULC changes would seem the most effective to address reservoir water
quality issues, and therefore territorial planning can play an important role in adaptation and mitigation in this region.The present research is co-funded by the European Union through the European Regional
Development Fund, included in the COMPETE 2020 (Operational Program Competitiveness
and Internationalization) through the ICT project (UIDB/04683/2020) with the reference
POCI-01-0145-FEDER-007690, the ALOP project (ALT20-03-0145-FEDER-000004)
Trypanosoma cruzi Adjuvants Potentiate T Cell-Mediated Immunity Induced by a NY-ESO-1 Based Antitumor Vaccine
Immunological adjuvants that induce T cell-mediate immunity (TCMI) with the least side effects are needed for the development of human vaccines. Glycoinositolphospholipids (GIPL) and CpGs oligodeoxynucleotides (CpG ODNs) derived from the protozoa parasite Trypanosoma cruzi induce potent pro-inflammatory reaction through activation of Toll-Like Receptor (TLR)4 and TLR9, respectively. Here, using mouse models, we tested the T. cruzi derived TLR agonists as immunological adjuvants in an antitumor vaccine. For comparison, we used well-established TLR agonists, such as the bacterial derived monophosphoryl lipid A (MPL), lipopeptide (Pam3Cys), and CpG ODN. All tested TLR agonists were comparable to induce antibody responses, whereas significant differences were noticed in their ability to elicit CD4+ T and CD8+ T cell responses. In particular, both GIPLs (GTH, and GY) and CpG ODNs (B344, B297 and B128) derived from T. cruzi elicited interferon-gamma (IFN-γ) production by CD4+ T cells. On the other hand, the parasite derived CpG ODNs, but not GIPLs, elicited a potent IFN-γ response by CD8+ T lymphocytes. The side effects were also evaluated by local pain (hypernociception). The intensity of hypernociception induced by vaccination was alleviated by administration of an analgesic drug without affecting protective immunity. Finally, the level of protective immunity against the NY-ESO-1 expressing melanoma was associated with the magnitude of both CD4+ T and CD8+ T cell responses elicited by a specific immunological adjuvant
Platelet-Activating Factor Receptor Plays a Role in Lung Injury and Death Caused by Influenza A in Mice
Influenza A virus causes annual epidemics which affect millions of people
worldwide. A recent Influenza pandemic brought new awareness over the health
impact of the disease. It is thought that a severe inflammatory response against
the virus contributes to disease severity and death. Therefore, modulating the
effects of inflammatory mediators may represent a new therapy against Influenza
infection. Platelet activating factor (PAF) receptor (PAFR) deficient mice were
used to evaluate the role of the gene in a model of experimental infection with
Influenza A/WSN/33 H1N1 or a reassortant Influenza A H3N1 subtype. The following
parameters were evaluated: lethality, cell recruitment to the airways, lung
pathology, viral titers and cytokine levels in lungs. The PAFR antagonist
PCA4248 was also used after the onset of flu symptoms. Absence or antagonism of
PAFR caused significant protection against flu-associated lethality and lung
injury. Protection was correlated with decreased neutrophil recruitment, lung
edema, vascular permeability and injury. There was no increase of viral load and
greater recruitment of NK1.1+ cells. Antibody responses were
similar in WT and PAFR-deficient mice and animals were protected from
re-infection. Influenza infection induces the enzyme that synthesizes PAF,
lyso-PAF acetyltransferase, an effect linked to activation of TLR7/8. Therefore,
it is suggested that PAFR is a disease-associated gene and plays an important
role in driving neutrophil influx and lung damage after infection of mice with
two subtypes of Influenza A. Further studies should investigate whether
targeting PAFR may be useful to reduce lung pathology associated with Influenza
A virus infection in humans
Enfermedades crónicas
Adherencia al tratamiento farmacológico y relación con el control metabólico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal crónico con hemodiálisis en Bogotá, ColombiaAmputación de extremidades inferiores: ¿están aumentando las tasas?Consumo de edulcorantes artificiales en jóvenes universitariosCómo crecen niños normales de 2 años que son sobrepeso a los 7 añosDiagnóstico con enfoque territorial de salud cardiovascular en la Región MetropolitanaEfecto a corto plazo de una intervención con ejercicio físico, en niños con sobrepesoEfectos de la cirugía bariátrica en pacientes con síndrome metabólico e IMC < 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades crónicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiología de las muertes hospitalarias por patologías relacionadas a muerte encefálica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4º medio de la Región de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluación del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en población universitaria de la Facsal, universidad de TarapacáImplicancias psicosociales en la génesis, evolución y tratamiento de pacientes con hipertensión arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducción de nuevas TIC y mejoría de la asistencia a un programa de saludNiños obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por cáncer de cuello uterino en Río de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicación en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en población preescolar y su relación con malnutrición por excesoPrevalencia de retinopatía diabética en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacológica antihipertensiva en población mapuche: Un estudio cualitativoRol biológico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad pública del estado de São Paul
Dinâmica da comunidade arbórea em um fragmento de floresta estacional semidecidual montana em Lavras, Minas Gerais, em diferentes classes de solos
Revista do Museu Paulista e(m) capas: identidade e representação institucional em texto e imagem
Este artigo propõe reflexão sobre a escrita da história, a partir de estudo das capas da Revista do Museu Paulista, especialmente durante as gestões dos dois primeiros diretores da instituição, quando certa continuidade editorial foi preservada. Tomadas como "fontes", ou seja, objeto de trabalho do historiador, as capas revelam vestígios de processos que permitem reconstruir, em suas dimensões históricas, as complexas imbricações entre a produção da Revista, sua materialidade, e os atos de leitura e interpretação que condicionam e refletem relações entre produtores de textos e seus leitores nas primeiras décadas do século XX, a partir de São Paulo, onde era editada.This paper offers a reflection about the writing of History, based on the study of Revista do Museu Paulista's covers, noticeably during the term of its two first directors, when a certain editorial continuity was preserved. Taken as "sources", namely as historian subjects, those covers reveal evidences of practices that allow one to reconstitute, in its historic dimensions, the complex connection between the creation of the Revista, its materiality, and the reading and interpretation efforts that condition and reflect liaisons with writers and readers during the first decades of the XXth Century, from São Paulo, where it was published.
Alteração de biomarcadores de lesão miocárdica em atletas após a Maratona Internacional de São Paulo
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