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Immune receptors and adhesion molecules in human pulmonary leptospirosis

Bernardi, Fabiola Del Carlo; Ctenas, Bruno; Ferraz da Silva, Luiz Fernando; Nicodemo, Antonio Carlos; Nascimento Saldiva, Paulo Hilario; Dolhnikoff, Marisa; Mauad, Thais
Fonte: W B SAUNDERS CO-ELSEVIER INC; PHILADELPHIA Publicador: W B SAUNDERS CO-ELSEVIER INC; PHILADELPHIA
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.58%
Pulmonary involvement in leptospirosis has been increasingly reported in the last 20 years, being related to the severity and mortality of the disease. The pathogenesis of pulmonary hemorrhage in leptospirosis is not understood. Lung endothelial cells have been proposed as targets in the pathogenesis of lung involvement in leptospirosis through the activation of Toll-like receptor 2 or the complement system, which stimulates the release of cytokines that lead to the activation of adhesion molecules. The aim of this study was to investigate the involvement of immune pathways and of the intercellular and vascular cell adhesion molecules (intercellular adhesion molecule and vascular cell adhesion molecule, respectively) in the lungs of patients with pulmonary involvement of leptospirosis. We studied the lungs of 18 patients who died of leptospirosis and compared them with 2 groups of controls: normal and noninfectious hemorrhagic lungs. Using immunohistochemistry and image analysis, we quantified the expression of the C3a anaphylatoxin receptor, intercellular adhesion molecule, vascular cell adhesion molecule, and Toll-like receptor 2 in small pulmonary vessels and in the alveolar septa. There was an increased expression of intercellular adhesion molecule (P <.03) and C3a anaphylatoxin receptor (P <.008) in alveolar septa in the leptospirosis group compared with the normal and hemorrhagic controls. In the vessels of the leptospirosis group...

Interações moleculares na adesão celular em suportes sólidos e o efeito de fotossensibilizadores porfirínicos; Molecular interactions in cell adhesion on solid substrates and the effect of porphyrinic photosensitizers

Santos, Patrícia Araújo dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/03/2013 PT
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36.62%
A adesão celular está ligada à formação e disseminação de metástases, a principal causa de óbito de pacientes diagnosticados com câncer. O objetivo deste trabalho foi investigar in vitro o efeito de fotossensibilizadores na adesão celular. Foram utilizadas porfirinas comerciais (PpIX, CPpI, TSPP, TMPyP e Zn(II)TMPyP) e um fotossensibilizador sintetizado através da ligação de poli-L-lisina à protoporfirina IX (PLLPpIX). A adesão celular foi estudada por RICM, técnica que permite quantificar a área de contato entre uma célula e um substrato por binarização das imagens digitais utilizando limiares apropriados. A técnica foi padronizada e revelou dois regimes de adesão celular: um limitado e outro não limitado pela quantidade de proteína de adesão adsorvida na superfície. Neste último foi observada lise celular. Todos os fotossensibilizadores estudados foram capazes de aumentar a adesão celular na ausência de irradiação comparados ao controle sem fotossensibilizador, o que não havia sido observado nos ensaios de resistência à tripsinização normalmente utilizados para estudar o efeito de fotossensibilizadores na adesão celular. Quanto maior a anfifilicidade do fotossensibilizador, maior foi o efeito na adesão...

Human eosinophil adhesion and degranulation stimulated with eotaxin and RANTES in vitro: Lack of interaction with nitric oxide

Lintomen, Letícia; Franchi, Gilberto; Nowill, Alexandre; Condino-Neto, Antonio; de Nucci, Gilberto; Zanesco, Angelina; Antunes, Edson
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.54%
Background: Airway eosinophilia is considered a central event in the pathogenesis of asthma. The toxic components of eosinophils are thought to be important in inducing bronchial mucosal injury and dysfunction. Previous studies have suggested an interaction between nitric oxide (NO) and chemokines in modulating eosinophil functions, but this is still conflicting. In the present study, we have carried out functional assays (adhesion and degranulation) and flow cytometry analysis of adhesion molecules (VLA-4 and Mac-1 expression) to evaluate the interactions between NO and CC-chemokines (eotaxin and RANTES) in human eosinophils. Methods: Eosinophils were purified using a percoll gradient followed byimmunomagnetic cell separator. Cell adhesion and degranulation were evaluated by measuring eosinophil peroxidase (EPO) activity, whereas expression of Mac-1 and VLA-4 was detected using flow cytometry. Results: At 4 h incubation, both eotaxin (100 ng/ml) and RANTES (1000 ng/ml) increased by 133% and 131% eosinophil adhesion, respectively. L-NAME alone (but not D-NAME) also increased the eosinophil adhesion, but the co-incubation of L-NAME with eotaxin or RANTES did not further affect the increased adhesion seen with chemokines alone. In addition...

Modulação da adesão plaquetaria de ratos tratados com lipopolissacarideo por especies reativas de oxigenio e nitrogenio; Reactive oxygen and nitrogen species modulate the ex-vivo effects of LPS on platelet adhesion to fibrinogen

Andre Luiz Casarin
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/01/2010 PT
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A sepse é um problema grave enfrentado em hospitais e por isso é importante mais estudos que possam esclarecer melhor a sua fisiopatologia. Alguns estudos indicam que as plaquetas podem ter um papel importante nesta condição, já que a gravidade da sepse relaciona-se positivamente com o estado de ativação destes elementos. O LPS é uma substância bastante utilizada no estudo da sepse, uma vez que mimetiza vários efeitos observados neste quadro como a grande produção de espécies reativas de oxigênio (EROs) e nitrogênio (ERNs). Portanto, o objetivo deste trabalho foi investigar as ações do tratamento de ratos com LPS na adesão plaquetária, bem como o envolvimento de EROs e ERNs na modulação deste(s) efeito(s). Para tanto, ratos foram injetados com LPS (1 mg/kg, i.p.) e após 2h a 48h a adesão plaquetária foi avaliada. As plaquetas aderidas aos poços foram quantificadas através da determinação da atividade da fosfatase ácida. Para investigar o papel do NO e de EROs no(s) efeito(s) do LPS na adesão plaquetária, foram realizados co-tratamentos de ratos com o inibidor da óxido sintase L-NAME ou com antioxidante N-acetilcisteína (NAC), bem como a incubação de plaquetas in vitro com o sequestrador de O2- PEG-SOD. Os níveis de GMPc em plaquetas foram determinados por radioimunoensaio. O tratamento de ratos com LPS aumentou a adesão de plaquetas não-ativadas ao fibrinogênio e diminuiu a adesão de plaquetas ativadas por trombina. O tratamento crônico dos ratos com L-NAME (20 mg/kg/dia) por 7 dias antes da injeção com LPS reduziu o aumento da adesão de plaquetas não-ativadas...

Investigação do papel do óxido nítrico e de Rho GTPases na adesão de neutrófilos sob condições inflamatórias = : Investigation of the role of nitric oxide and Rho GTPases in neutrophils adhesion under inflammatory conditions; Investigation of the role of nitric oxide and Rho GTPases in neutrophils adhesion under inflammatory conditions

Angélica Aparecida Antoniellis Silveira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/09/2012 PT
Relevância na Pesquisa
36.58%
Durante a resposta inflamatória, os neutrófilos e outros leucócitos aderem ao endotélio, deixando os vasos sanguíneos e movimentando-se ativamente em direção ao foco inflamatório. A migração dos neutrófilos para sítios inflamatórios depende de uma série de eventos adesivos e quimiotáticos, resultantes da ativação de moléculas de adesão como as selectinas e integrinas e receptores de quimiocinas. Devido às suas propriedades, os neutrófilos podem ser ativados por proteínas de sinalização intracelular, as Rho GTPases, que auxiliam os neutrófilos a desempenhar esta função por interferirem em mudanças no citoesqueleto. Estas proteínas também estão envolvidas na adesão e proliferação celular. Os neutrófilos são capazes de sintetizar óxido nítrico (NO), sendo que esta produção de NO é um importante componente da resposta imune inata durante a inflamação. Estudos demonstraram que os neutrófilos têm papel indutor na geração de inflamação e esforços visando compreender o mecanismo adesivo destas células nos processos inflamatórios podem ser um ponto chave para intervenções farmacológicas em doenças que são caracterizadas por inflamação vascular com consequente obstrução de fluxo sanguíneo. Diante disso...

Efeito da hidroxiureia na adesão in vitro de neutrófilos, sob condições inflamatórias = : Effect of hydroxyurea on the adhesion of neutrophil under in vitro inflammatory conditions; Effect of hydroxyurea on the adhesion of neutrophil under in vitro inflammatory conditions

Daiana Morelli Vital
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/01/2015 PT
Relevância na Pesquisa
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A inflamação é uma resposta fisiológica normal à infecção ou lesão tecidual que permite a sobrevivência do indivíduo a diversos agentes lesivos e mantém a homeostase dos tecidos sob uma variedade de condições nocivas. Os neutrófilos têm um papel importante em processos inflamatórios e, na presença de estímulos inflamatórios, como citocinas e quimiocinas, são recrutados da circulação para o tecido inflamado por uma sequência de interações adesivas. Recentemente, novas técnicas in vitro têm levado a importantes avanços no entendimento de patologias vasculares e hematológicas e sistemas microfluídicos, que mimetizam a microcirculação humana, demonstrando a utilidade para o estudo de interações adesivas de células inflamatórias. As interações dos neutrófilos e outros leucócitos com a parede vascular tem contribuição importante para as doenças inflamatórias crônicas, como a anemia falciforme (AF) e aterosclerose, pois podem participar em processos de oclusão vascular. O objetivo deste trabalho foi avaliar se a hidroxiureia (HU), uma droga utilizada como terapia na AF, modula as propriedades adesivas de neutrófilos quando incubados in vitro com a droga e frente um estímulo inflamatório. Os neutrófilos...

Potential of the adhesion of bacteria isolated from drinking water to materials

Simões, Lúcia C.; Simões, M.; Oliveira, Rosário; Vieira, M. J.
Fonte: WILEY-VCH Verlag Publicador: WILEY-VCH Verlag
Tipo: Artigo de Revista Científica
Publicado em /04/2007 ENG
Relevância na Pesquisa
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Heterotrophic bacteria (11 genera, 14 species, 25 putative strains) were isolated from drinking water, identified either biochemically or by partial 16s rDNA gene sequencing and their adherence characteristics were determined by two methods: i. thermodynamic prediction of adhesion potential by measuring hydrophobicity (contact angle measurements) and ii. by measuring adherence to eight different substrata (ASI 304 and 316 stainless steel, copper, polyvinyl chloride, polypropylene, polyethylene, silicone and glass). All the test organisms were hydrophilic and inter-species variation in hydrophobicity occurred only for Comamonas acidovorans. Stainless steel 304 (SS 304), copper, polypropylene (PP), polyethylene (PE) and silicone thermodynamically favoured adhesion for the majority of test strains (>18/25), whilst adhesion was generally less thermodynamically favorable for stainless steel 316 (SS 316), polyvinyl chloride (PVC) and glass. The predictability of thermodynamic adhesion test methods was validated by comparison with 24-well microtiter plate assays using nine reference strains and three adhesion surfaces (SS 316, PVC and PE). Results for Acinetobacter calcoaceticus, Burkolderia cepacia and Stenotrophomonas maltophilia sp. 2 were congruent between both methods whilst they differed for the other bacteria to at least one material. Only A. calcoaceticus had strongly adherent properties to the three tested surfaces. Strain variation in adhesion ability was detected only for Sphingomonas capsulata. Analysis of adhesion demonstrated that in addition to physicochemical surface properties of bacterium and substratum...

Advances in adhesion between polymers and concrete

Aguiar, J. L. Barroso de; Gemert, D. van
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2007 ENG
Relevância na Pesquisa
36.57%
The adhesion between polymers and concrete is complex and needs to be studied with adequate methods. One problem is about the best test to determine adhesion strength. The use of traditional tests like direct tension, flexure or shear, normally does not enable the correct determination of the adhesion strength. If the adhesive is good and the substrate’s surfaces are well prepared, the failure is in the substrate. With this kind of faitures it is possible to say that adhesion strength is higher than the failure stress. It is not possible to give a numerical value of adhesion strength. A test based on fracture mechanics makes the determination of adhesion strength easier. The use of a notched specimen concentrates the stresses in the poliymer/substrate joint and adhesive failures are more frequent. With adhesive failures, it is possibie to determine the numerical value of the adhesion strength. The results’ analysis of adhesion tests needs to be made using appropriate methods. The presentation of the results is made in accordance with a square optimisation method where the adhesion in tension and the failure mode are taken into consideration. The use of this method is exemplified with results of adhesion tests for concrete/epoxies resins. The incorporation of fillers into the epoxies enabies a good adhesion even when Lhe concrete is wet. Tension tests were made to study the influence of the type...

Bacterial adhesion to worn silicone hydrogel contact lenses

Santos, Lívia; Rodrigues, Diana; Lira, Madalena; Oliveira, M. Elisabete; Oliveira, Rosário; Yebra-Pimentel Vilar, Eva; Azeredo, Joana
Fonte: American Academy of Optometry Publicador: American Academy of Optometry
Tipo: Artigo de Revista Científica
Publicado em /07/2008 ENG
Relevância na Pesquisa
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Purpose. The aim of this study was to, firstly, investigate whether silicone-hydrogel contact lenses (CL) are more or less susceptible to bacterial adhesion than conventional ones and, secondly, assess the influence of lens wear in the extent of bacterial adhesion. Four silicone-hydrogel CL (galyfilcon A, balafilcon A, lotrafilcon A, and lotrafilcon B) and one conventional hydrogel (etafilcon A) CL were tested. Methods. Bacterial adhesion experiments were performed on unworn and worn CL using the strain Staphylococcus epidermidis 9142. Worn lenses were obtained from a group of 31 subjects fitted with a silicone-hydrogel CL in one eye and a conventional hydrogel CL as contralateral pair. These lenses were used on a daily basis in combination with a multipurpose lens care solution. Adhesion assays were carried out in a parallel plate flow chamber, followed by image analysis. Hydrophobicity, roughness, and topography of the lenses surfaces were assessed through contact angle measurements and atomic force microscopy. Results. Unworn conventional and silicone-hydrogel CL were equally susceptible to bacterial adhesion of S. epidermidis. Conversely, worn conventional hydrogel (etafilcon A) were more prone to bacterial adhesion than worn silicone-hydrogel materials...

Adhesion and biofilm formation on polystyrene by drinking water-isolated bacteria

Simões, Lúcia C.; Simões, M.; Vieira, M. J.
Fonte: Springer Science+Business Media Publicador: Springer Science+Business Media
Tipo: Artigo de Revista Científica
Publicado em //2010 ENG
Relevância na Pesquisa
36.58%
This study was performed in order to characterize the relationship between adhesion and biofilm formation abilities of drinking water-isolated bacteria (Acinetobacter calcoaceticus, Burkholderia cepacia, Methylobacterium sp., Mycobacterium mucogenicum, Sphingomonas capsulata and Staphylococcus sp.). Adhesion was assessed by two distinct methods: thermodynamic prediction of adhesion potential by quantifying hydrophobicity and the free energy of adhesion; and by microtiter plate assays. Biofilms were developed in microtiter plates for 24, 48 and 72 h. Polystyrene (PS) was used as adhesion substratum. The tested bacteria had negative surface charge and were hydrophilic. PS had negative surface charge and was hydrophobic. The free energy of adhesion between the bacteria and PS was[0 mJ/m2 (thermodynamic unfavorable adhesion). The thermodynamic approach was inappropriate for modelling adhesion of the tested drinking water bacteria, underestimating adhesion to PS. Only three (B. cepacia, Sph. capsulata and Staphylococcus sp.) of the six bacteria were non-adherent to PS. A. calcoaceticus, Methylobacterium sp. and M. mucogenicum were weakly adherent. This adhesion ability was correlated with the biofilm formation ability when comparing with the results of 24 h aged biofilms. Methylobacterium sp. and M. mucogenicum formed large biofilm amounts...

Abdominal adhesion prevention: Still a sticky subject?

Lauder, C.; Garcea, G.; Strickland, A.; Maddern, G.
Fonte: Karger Publicador: Karger
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
36.54%
BACKGROUND: Adhesion formation remains an almost inevitable consequence of abdominal procedures, potentially resulting in significant morbidity and mortality. There is an ongoing need to evaluate current understanding of adhesion formation and products aimed at prevention. Failure to keep up to date with adhesion treatment may subject clinicians to a greater medico-legal risk. DESIGN: Review of published studies exploring the problem of peritoneal adhesion formation. This encompasses the underlying processes of adhesion formation combined with general approaches to reduce formation. An overview of products trialled to prevent formation in both the animal model and clinical setting describes products of scientific interest and commercial success. RESULTS: Advances in surgical technique, such as laparoscopic surgery, can help minimize the probability of adhesion formation. Currently barrier products, whilst reducing adhesion formation, have not been shown to reduce the risk of readmission with complications related to adhesions. Hybrid products may improve upon this situation. CONCLUSIONS: No single approach has been wholly satisfactory in reducing adhesions. Research into the processes driving adhesion formation is providing exciting new targets for therapeutic agents. It would seem plausible that with many promising avenues of research a revolutionary agent to reduce the incidence of adhesional small bowel obstruction may result.; Chris I.W. Lauder...

Peritoneal adhesion formation and modulation.

Lauder, Christopher Ian William
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2011
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36.55%
This thesis examines the subject of peritoneal adhesion formation following surgery in the format of a Master of Surgery by publication. A comprehensive literature review examines all aspects of peritoneal adhesions from the basic science to the evidence supporting products aimed at adhesion reduction. Subsequent experimental work utilises two animal models to form adhesions and test the ability of a novel gel product to reduce adhesion formation. The gel is a hybrid hydrogel consisting of modified chitosan and dextran. These two components are combined by a chemical cross linking reaction to form an inert gel that can be applied to the site of surgery. The gel confers several beneficial properties when used to prevent adhesions. Firstly it provides a physical separation of the injured peritoneal surfaces whilst also inhibiting the ingress of fibroblasts to the area. Secondary characteristics which promote haemostasis and inhibit bacterial growth enhance the gels adhesion reducing potential. Initially the gel was trialled in a small animal model to test varying compositions and volumes of the gel. Two different surgical models of adhesion formation were utilised to provide a range of stimuli in the post operative period. Results from these experiments were encouraging...

Anti-adhesion barrier gels following operative hysteroscopy for treating female infertility: a systematic review and meta-analysis

Bosteels, J.; Weyers, S.; Mol, B.; D'Hooghe, T.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
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36.55%
The aim of this study was to assess the effects of any anti-adhesion barrier gel used after operative hysteroscopy for treating infertility associated with uterine cavity abnormalities. Gynecologists might use any barrier gel following operative hysteroscopy in infertile women for decreasing de novo adhesion formation; the use of any barrier gel is associated with less severe de novo adhesions and lower mean adhesion scores. Nevertheless, infertile women should be counseled that there is at the present no evidence for higher live birth or pregnancy rates. There is a lack of data for the outcome miscarriage. Preclinical studies suggest that the use of biodegradable surgical barriers may decrease postsurgical adhesion formation. Observational studies in the human report conflicting results. We searched the Cochrane Menstrual Disorders and Subfertility Specialized Register (10 April 2013), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 1), MEDLINE (1950 to 4 April 2013), EMBASE (1974 to 4 April 2013), and other electronic databases of trials including trial registers, sources of unpublished literature, and reference lists. We handsearched the Journal of Minimally Invasive Gynecology (from 1 January 1992 to 13 April 2013); we also contacted experts in the field. We included the randomized comparisons between any anti-adhesion barrier gel versus another barrier gel...

Challenges of the accession of Turkey into the European Union; Retos de la adhesión de Turquía a la Unión Europea

Serrano, Enriqueta; Navarrete Ortiz, Paola
Fonte: Universidade do Rosário Publicador: Universidade do Rosário
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em 02/07/2011 SPA
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36.54%
Turkey's accession to the European Union (EU) has become, over the years, one of the most contentious issues of European integration. On October 3rd 2005, the European Commission began negotiations for its accession, and, although they will probably not be completed within a decade, its objective is the full accession to the Union. Turkey's accession to the EU presents challenges for both parties, but especially for the European Union. There are very different challenges from the previous accessions, indeed. This work aims to analyze the challenges the EU will face towards Turkey's possible accession to the European Community. Therefore, this work has been divided into three sections. In the first of them, entitled "Brief history of a complex negotiation", the negotiation is briefly described. The second, "Aspects to take into account for Turkey's accession to the European Union", in which different relevant (geopolitical, economic and financial, demographic, cultural and religious) aspects of the possible a cession are discussed: aspects that will have an important impact in the development and performance of the European Community, once accession is fulfilled. The third and last section, "Turkey's incorporating challenges", discusses the challenges the EU will have to face with the potential accession of Turkey...

Factores de adhesión de Rhizobium leguminosarum y su rol en la formación de biofilms; Adhesion factors from Rhizobium leguminosarum and their role on biofilm formation

Vozza, Nicolás Federico
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2012 SPA
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36.58%
Rhizobium leguminosarum es una α-proteobacteria que puede establecer simbiosis con ciertas leguminosas. La formación de un biofilm puede favorecer la persistencia en suelos y en la rizosfera y también contribuir a la competitividad para la infección de la leguminosa. En esta tesis se estudiaron factores importantes para la adhesión a diversos sustratos y la formación de biofilms. Uno de los factores estudiados fue la proteína de adhesión RapA1, secretada a través del sistema PrsDE. Se sobreexpresó RapA1 y se observó que esto produjo diversos fenotipos de superficie, incluido el aumento de adhesión a sustratos abióticos y la formación aumentada de biofilms in vitro. Se estudió la relación entre RapA1 y el exopolisacárido acídico (EPS) y el requerimiento del EPS y PrsDE para formar biofilms en flujo continuo. Se analizó la localización de RapA1 y de otras proteínas relacionadas y se estudiaron posibles mecanismos involucrados en la localización. Algunos estudios complementarios sobre el efecto de RapA1 sobre la superficie, efecto de expresión de otras Raps y regulación de genes relacionados con la adhesión fueron encarados de manera inicial. La interacción entre Polisacáridos de superficie y adhesinas proteicas resulta clave para la adhesión y formación de biofilms...

Participación de EPAC en procesos de adhesión, migración y contracción de geles de colágeno en fibroblastos y miofibroblastos cardiacos de ratas neonatas

Guzmán Muñoz, Nancy Alejandra
Fonte: Universidad de Chile; CyberDocs Publicador: Universidad de Chile; CyberDocs
Tipo: Tesis
ES
Relevância na Pesquisa
36.55%
Memoria para optar al título de Químico Farmacéutico; El corazón está constituido por numerosos tipos celulares, de los cuales el 90% corresponde a cardiomiocitos y fibroblastos. Los fibroblastos representan dos tercios de la población celular del corazón y están encargados principalmente del recambio de las proteínas de la matriz extracelular. Estas células tienen la capacidad de responder a una variedad de citoquinas, factores de crecimiento y expresan sus receptores indicando que pueden responder de manera autocrina; y por la acción de TGF-1, se diferencian a miofibroblastos, un fenotipo celular altamente secretor de colágeno y principal encargado del proceso de cicatrización. Por otro lado, existen numerosos antecedentes que demuestran que en fibroblastos cardiacos, la activación de las vías de transducción que conducen al aumento del AMPc contribuye a la reducción de la fibrosis cardiaca, por regular procesos antifibróticos entre ellos disminuir la adhesión, migración y la diferenciación a miofibroblasto. Recientemente se ha descrito en la literatura a la proteína EPAC-1 (del acrónimo exchange protein activated directly by cAMP), quien a través de las GTPasas pequeñas Rap 1 y Rap 2 modula secreción de colágeno y migración. Sin embargo...

Quantitative analysis of bacterial adhesion to fish tissue

Vendrell, Daniel; Balcázar, José Luis; Calvo, Ana Cristina; Blas, Ignacio de; Ruiz-Zarzuela, Imanol; Gironés, Olivia; Múzquiz, José Luis
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 918459 bytes; application/pdf
ENG
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3 pages, 1 figure.-- PMID: 19349152 [PubMed].-- Printed version published Jul 1, 2009.; Adhesion to host tissue represents a first crucial step in most bacterial infections. Both specific adhesion-ligand as well as hydrophobic interactions may be involved. The adhesion of Aeromonas salmonicida subsp. salmonicida, Lactococcus garvieae, and Yersinia ruckeri strains to fish tissue cells was assessed. To determine whether the observed bacterial adhesion to fish tissue cells was caused by non-specific interactions, adhesion to bovine serum albumin (BSA) and polystyrene was also tested. Our results demonstrated that non-specific adhesion such as hydrophobic interactions are only partially involved in the binding process since adhesion to BSA was low, and there was no correlation between adhesion to polystyrene and adhesion to fish tissue cells.; This study was supported by a grant from the National Adviser Body of Continental Cultures (JACUCON). J. L. Balcázar was supported by a fellowship from the Spanish International Cooperation Agency (AECI).; Peer reviewed

Use of high-temperature and high humidity to test the adhesion of sputtered copper to a polyimide surface-modified by an AC Nitrogen Glow-Discharge

JB, MA; VanDerveer, William; Entenberg, Alan; Lindberg, Vern; Anschel, M.; Shih, Dy; Lauro, P.
Fonte: Brill (VSP): Journal of Adhesion Science and Technology Publicador: Brill (VSP): Journal of Adhesion Science and Technology
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.51%
We have used an extreme environmental stress test to study the adhesion of a thin sputtered copper film (0.5 mu m) to flexible polyimide (PI) substrates between 25 and 125 mu m thick. The polyimide types include Kapton (PMDA-ODA) and Upilex (BPDA-PDA). When there was no surface modification on the PI, the adhesion of the film to Upilex type S was better than the adhesion to Upilex type R or Kapton type HN. When the polymer surface was treated with a simple AC nitrogen glow discharge (NGD), there was an improvement in the adhesion of the film to each of these polyimides. This improvement in adhesion became apparent after the film/substrate combination was subjected to either boiling water or steam for 30 min or more; the difference became quite clear after 2 h. A simple tape test was used to quickly estimate a relative adhesion strength. In order to compare the effect of our AC NGD treatment with other substrate surface modification methods, we used it to improve the coupling of a thick (>10 mu m) layer of copper (via a thin intermediate chromium layer) to a rigid PI substrate, formed from spin coating its precursor onto a silicon wafer. Peel test results were within a factor of 2-3 of the corresponding results obtained with a radio frequency (RF) plasma and ion beam treatments.

Adhesion of copper to poly(tetrafluoroethylene) surfaces modified with vacuum UV radiation from helium arc plasma

Zheng, S.; Entenberg, Alan; Takacs, Gerald; Egitto, F.; Matienzo, L.
Fonte: Springer-Verlag: Journal of Adhesion Science and Technology Publicador: Springer-Verlag: Journal of Adhesion Science and Technology
Tipo: Abstract Formato: 43151 bytes; application/pdf
EN_US
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46.31%
Poly(tetrafluoroethylene) (PTFE) film surfaces were exposed to vacuum UV (VUV) radiation from He dc arc plasmas that were made to rotate inside a graphite tube by the application of an auxiliary magnetic field. The films were covered with optical filters having different cutoff wavelengths to vary the VUV radiation that modified the fluoropolymer surface. Photo-etching was detected, as well as surface modification that showed the following: (1) water contact angles decreasing with wavelengths of 173 nm or shorter; (2) surface roughening; (3) defluorination of the surface and formation of cross-linking bonds in the top 10 nm of the surface as detected by XPS analysis; and (4) incorporation of oxygen upon exposure to air. An improvement in the adhesion of copper to these modified surfaces was observed.; RIT community members may access full-text via RIT Libraries licensed databases: http://library.rit.edu/databases/

Prevalencia de la adhesión a la restricción de líquidos en pacientes renales en hemodiálisis: indicador objetivo y adhesión percibida

Iborra-Moltó,Carmelo; López-Roig,Sofía; Pastor-Mira,M. de los Ángeles
Fonte: Nefrología (Madrid) Publicador: Nefrología (Madrid)
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/01/2012 SPA
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Introducción: Los estudios sobre adhesión a la restricción de líquidos muestran alta variabilidad en los datos de prevalencia debido a los distintos métodos de medida de la ganancia interdiálisis (GID) y los criterios de punto de corte utilizados. Objetivos: Describir la prevalencia de adhesión a la restricción hídrica según la GID diaria (criterio: ≤ 1 kg) y la GID diaria ajustada al peso seco (PS) (criterio: PS < 70 kg, GID = 1 kg/día; PS > 70 y ≤ 80 kg, GID = 1,1 kg/día; PS > 80 y ≤ 90 kg, GID = 1,2 kg/día; PS > 90 kg, GID = 1,3 kg/día); y estudiar la asociación entre este indicador objetivo y la conducta de adhesión referida por el paciente. Pacientes y métodos: 146 pacientes. Edad media: 66,1 años (desviación típica [DT]: 13,6; rango: 25-88); un 66,4% varones. Estudio longitudinal con un mes de seguimiento. Variables: sociodemográficas. Clínicas. GID diaria. Conducta de adhesión referida, evaluada mediante entrevista por personal entrenado ajeno al servicio, con la pregunta "Para evitar complicaciones entre las hemodiálisis: ¿Durante el último mes, ha tomado usted menos de un litro de líquidos al día? (0 = Ningún día; 10 = Todos los días)". Los pacientes fueron clasificados como cumplidores a partir de valores ≥ 5. Análisis estadístico: descriptivo...