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Porcine skin as a source of biodegradable matrices: alkaline treatment and glutaraldehyde crosslinking

RODRIGUES, Fabiana T.; MARTINS, Virginia C. A.; PLEPIS, Ana M. G.
Fonte: Associação Brasileira de Polímeros Publicador: Associação Brasileira de Polímeros
Tipo: Artigo de Revista Científica
ENG
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In this work, the modifications promoted by alkaline hydrolysis and glutaraldehyde (GA) crosslinking on type I collagen found in porcine skin have been studied. Collagen matrices were obtained from the alkaline hydrolysis of porcine skin, with subsequent GA crosslinking in different concentrations and reaction times. The elastin content determination showed that independent of the treatment, elastin was present in the matrices. Results obtained from in vitro trypsin degradation indicated that with the increase of GA concentration and reaction time, the degradation rate decreased. From thermogravimetry and differential scanning calorimetry analysis it can be observed that the collagen in the matrices becomes more resistant to thermal degradation as a consequence of the increasing crosslink degree. Scanning electron microscopy analysis indicated that after the GA crosslinking, collagen fibers become more organized and well-defined. Therefore, the preparations of porcine skin matrices with different degradation rates, which can be used in soft tissue reconstruction, are viable.

Mechanical, thermal and morphological properties of glutaraldehyde crosslinked bovine pericardium followed by glutamic acid treatment

GOISSIS, Gilberto; BRAILE, Domingo Marcolino; CARNEVALLI, Nélly Cristina; RAMIREZ, Vladimir Aparecido
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica
ENG
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Major problems with valve bioprostheses are associated with progressive structural deterioration and calcification, directly associated with the use of glutaraldehyde (GA). This work describes the effects of GA processing and borate/glutamic acid buffer treatment on the mechanical, thermal and morphological properties of 0.5% GA crosslinked bovine pericardium (BP). The results showed that while the treatment of 0.5% GA crosslinked BP with borate/glutamic acid significantly improves the mechanical properties, it had no visible effect on surface morphology. Better surface preservation was only achieved for BP pre-treated with a lower GA concentration followed by the conventional treatment (0.5% GA). Improvements in mechanical properties probably arises from structural changes probably involving the depolymerization of polymeric GA crosslinks and an increase electrostatic interaction due to covalent binding of glutamic acid to free carbonyl groups (Schiff base).The results indicate that the treatment GA crosslinked BP with borate/glutamic acid buffer may be an attractive procedure for the manufacture of heart valve bioprostheses.; FAPESP

Effect of freeze-drying on the mechanical, physical and morphological properties of glutaraldehyde-treated bovine pericardium: evaluation of freeze-dried treated bovine pericardium properties

BORGOGNONI, Camila F.; MAIZATO, Marina J. S.; LEIRNER, Adolfo A.; POLAKIEWICZ, Bronislaw; BEPPU, Marisa M.; HIGA, Olga Z.; PITOMBO, Ronaldo N. M.
Fonte: WICHTIG EDITORE Publicador: WICHTIG EDITORE
Tipo: Artigo de Revista Científica
ENG
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Purpose: Biomaterials have been widely used in the field of regenerative medicine. Bovine pericardium tissue has been successfully used as a bioprosthetic material in manufacturing heart valves, but studies concerning the tissue are ongoing in order to improve its storage, preservation and transportation. This article provides an overview of the characteristics of bovine pericardium tissue chemically treated after the freeze-drying process. These characteristics are essential to evaluate the changes or damage to the tissue during the process. Methods: The mechanical properties of the tissue were analyzed by three different methods due to its anisotropic characteristics. The physical properties were analyzed by a colorimetric method, while the morphological properties were evaluated by scanning electron microscopy (SEM). Results: The freeze-dried bovine pericardium showed no significant change in its mechanical properties. There was no significant change in the elasticity of the tissue (p > 0.05) and no color change. In addition, SEM analysis showed that the freeze-dried samples did not suffer structural collapse. Conclusions: It was concluded that glutaraldehyde-treated bovine pericardium tissue showed no significant change in its properties after the freeze-drying process.; State of Sao Paulo Research Foundation (FAPESP)

Influence of glutaraldehyde priming on bond strength of an experimental adhesive system applied to wet and dry dentine

CILLI, Renato; PRAKKI, Anuradha; ARAUJO, Paulo Amarante de; PEREIRA, Jose Carlos
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
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Objectives: This study tested the following null hypotheses: (1) there is no difference in resin-dentine bond strength when an experimental glutaraldehyde primer solution is added prior to bonding procedures and (2) there is no difference in resin-dentine bond strength when experimental glutaraldehyde/adhesive system is applied under dry or wet demineralized dentine conditions. Methods: Extracted human maxillary third molars were selected. Flat, mid-coronal dentine was exposed for bonding and four groups were formed. Two groups were designated for the dry and two for the wet dentine technique: DRY: (1) Group GD: acid etching + glutaraldehyde primer (primer A) + HEMA/ethanol primer (primer B)-under dried dentine + unfilled resin; (2) Group D: the same as GD, except for primer A application; WET: (3) Group GW: the same as GD, but primer B was applied under wet dentine condition; (4) Group W: the same as GW, except for primer A application. The bonding resin was light-cured and a resin core was built up on the adhesive layer. Teeth were then prepared for microtensile bond testing to evaluate bond strength. The data obtained were submitted to ANOVA and Tukey`s test (alpha = 0.05). Results: Glutaraldehyde primer application significantly improved resin-dentine bond strength. No significant difference was observed when the same experimental adhesive system was applied under either dry or wet dentine conditions. These results allow the first null hypothesis to be rejected and the second to be accepted. Conclusion: Glutaraldehyde may affect demineralized dentine properties leading to improved resin bonding to wet and dry substrates. (C) 2008 Elsevier Ltd. All rights reserved.; CAPES (Coordena do de Aperfeicoamento de Pessoal de Nivel Superior); Bauru Dental School...

Reticulacao de pericardio bovino com glutaraldeido: efeitos da temperatura , tempo de reação e concentração.; Crossliking of bovine pericardium with glutaraldehyde:effect of temperature, reaction time and concentration.

Piza, Marcos Antônio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/02/1997 PT
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Este trabalho teve como objetivo o desenvolvimento de um método de reticulação mais homogênea no pericárdio bovino (PB), utilizado na confecção de válvulas cardíacas, seguindo um tratamento seqüencial e não seqüencial com concentrações crescentes de glutaraldeído (GA), no intervalo entre 0,0010/0e 0,5%, com tempos de reação entre 5 e 90min, e temperatura entre 5 e 45°C. Os resultados de temperatura de encolhimento (Is) mostraram que a reticulação do pericárdio bovino é heterogênea, principalmente para baixas concentrações de glutaraldeído (0,001%). Entretanto esta heterogeneidade é menos perceptível para concentrações superiores de GA, principalmente para o tratamento seqüencial, sugerindo uma melhor qualidade de reação de reticulação. Em todos os tratamentos realizados, os melhores resultados foram obtidos para o tratamento seqüencial a 45°C, para 90 minutos de reação e 0,10/0 de GA, onde os valores de Ts (≅ 90°C) foram muito próximos daqueles para concentrações superiores de GA (0,5%). Encontrou-se também, nestas condições, os menores valores de hidrólise enzimática (colagenase = 3,80/0e tripsina =1,90/0 ). Estes comportamentos devem estar associados a uma maior concentração de GA monomérico e...

Caracterização In Vitro e In Vivo do pericárdio bovino reticulado com acetais do glutaraldeído para manufatura de biopróteses valvulares cardíacas.; Characterization in vitro and in vivo of bovine pericardium cross-linked with glutaraldehyde acetals for the manufacture of cardiac valve bioprostheses.

Yoshioka, Sergio Akinobu
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 02/06/2000 PT
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Este trabalho descreve a reação de reticulação alternativa do pericárdio bovino com os acetais do glutaraldeído, preparados a partir da solução de glutaraldeído na presença do etanol em meio ácido. Os acetais difundem para dentro da matriz colagênica, e a reticulação ocorre após a desproteção dos grupos aldeídicos com uma amina terciária. O material obtido sob estas condições mostrou as propriedades biológicas e mecânicas similares ou superiores àqueles descritos para o pericárdio bovino reticulado pelo procedimento convencional com glutaraldeído, e provavelmente, com resultados de uma distribuição e natureza química mais homogênea das reticulações formadas, devido à ausência das reticulações polímeros de glutaraldeído. As biopróteses manufaturadas com pericárdio reticulado com acetais do glutaraldeído, também mostraram durabilidade superior e foi menos suscetível ao processo de calcificação, como determinado em implantes subcutâneos em ratos. Resultados preliminares de teste à fadiga e performance hidrodinâmica foram caracterizados por um comportamento similar àqueles materiais tratados convencionalmente sugerindo que, o pericárdio reticulado com acetais do glutaraldeído pode ser um procedimento alternativo e mais eficiente na manufatura das biopróteses...

Síntese e caracterização de membranas de filme fino composto de polissulfona/quitosana reticulada com glutaraldeído.; Synthesis and characterization of thin film composite membranes of polysulfone/chitosan crosslinked with glutaraldehyde.

Nogueira, Fabiana Tavares
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 18/05/2012 PT
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Um grande obstáculo a ser vencido para que se tenha uma maior utilização da tecnologia de membranas na purificação de líquidos é o fenômeno do fouling. Como consequência, o desenvolvimento de membranas menos propensas ao fouling é hoje objeto de inúmeras pesquisas. Dentre os processos estudados, tem-se o desenvolvimento de membranas de filme fino composto, que possui como vantagem a possibilidade de se melhorar cada camada de maneira independente, de forma a se aperfeiçoar o desempenho da membrana como um todo. O projeto de pesquisa foi desenvolvido no laboratório do Centro Internacional de Referência em Reúso de Água (CIRRA/IRCWR), uma entidade sem fins lucrativos, vinculado ao Departamento de Engenharia Hidráulica e Ambiental da Escola Politécnica da Universidade de São Paulo (USP). Este teve como objetivo a síntese e a caracterização de membranas de filme fino composto de polissulfona e quitosana reticulada com glutaraldeído. Embora o objetivo principal desse trabalho tenha sido o desenvolvimento de membranas menos propensa ao fouling, a susceptibilidade ao fouling das membranas produzidas foi avaliada de maneira indireta, através da avaliação de propriedades como hidrofilicidade e rugosidade da superfície. Membranas de ultrafiltração a base de polissulfona (PSF) foram produzidas...

Análise microbiológica do glutaraldeído após sucessivas imersões de impressões de alginato; Microbiological analysis of glutaraldehyde after successive immersions of alginate impressions

Meira, Daniela Martins; Leitune, Vicente Castelo Branco; Collares, Fabrício Mezzomo; Sand, Sueli Teresinha van der; Samuel, Susana Maria Werner
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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Objetivo: O objetivo deste estudo foi avaliar através da análise de sua ação bacteriostática e bactericida, a eficácia de uma solução de glutaraldeído 2% após receber sucessivas imersões de impressões de alginato, contaminadas. Materiais e métodos: Foram coletadas sete amostras do desinfetante em uso. A avaliação da ação bacteriostática, das amostras se deu pela presença de bactérias viáveis através do método de Contagem Padrão em Ágar. Para a avaliação da ação bactericida, placas foram inoculadas com Escherichia. coli, Pseudomonas aeruginosa, e Staphylococcus aureus. Poços com 0,9 cm de diâmetro, realizados no meio de cultura das placas, receberam alíquotas de 100L de glutaraldeído, de cada amostra. As placas foram mantidas entre 8-10C, por 16 horas para difusão do composto. Após as placas foram para estufa a 37C, por 24 horas. A atividade antibacteriana foi avaliada pela presença de zonas de inibição de crescimento bacteriano em torno dos poços onde o glutaraldeído foi colocado. Resultados: Os resultados mostram que não houve crescimento bacteriano em nenhuma amostra e que todas as placas inoculadas mostraram zona de inibição pela ação do glutaraldeído. Conclusão: O delineamento deste estudo permite concluir que pelo menos...

Influência do tempo na desinfecção de alginato contaminado com Staphylococcus aureus em ácido peracético ou gluataraldeído; Influence of the time for the disinfection of alginate infected with Staphylococcus aureus in glutaraldehyde and peracetic acid

Meira, Daniela Martins; Collares, Themis; Sand, Sueli Teresinha van der; Collares, Fabrício Mezzomo; Leitune, Vicente Castelo Branco; Samuel, Susana Maria Werner
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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Objetivo: O objetivo deste estudo foi avaliar a eficácia do ácido peracético e do glutaraldeído na desinfecção do alginato contaminado com Staphylococcus aureus em função do tempo de imersão (10 e 5 min). Materiais e métodos: Os corpos de prova foram previamente contaminados com S. aureus e em seguida divididos em seis grupos de acordo com a substância desinfetante e o tempo de imersão. As amostras foram incubadas em 20 mL de caldo BHI estéril em estufa a 35± 2 ºC, sob agitação de 100 rpm, por 16 horas. Posteriormente as amostras do caldo de todos os tubos de ensaio foram semeadas para determinar a presença ou ausência de células viáveis. Resultados: Os resultados mostraram que os grupos controle e o lavado em água estéril apresentaram crescimento bacteriano. Conclusão: O ácido peracético foi igualmente eficaz ao glutaraldeído para desinfecção, do alginato contaminado com S. aureus, por imersão tanto no tempo de 10 quanto 5 minutos.; Objective: The aim of this study was to evaluate the effectiveness of peracetic acid and glutaraldehyde for the disinfection of alginate contaminated with Staphylococcus aureus as a function of immersion time (10 and 05 min). Materials and methods: The specimens were previously contaminated with S. aureus and then divided into six groups based on the disinfectant substance and immersion time. The samples were incubated in 20 ml of sterile BHI broth in an oven at 35 ± 2 °C and shakd at 100 rpm for 16 hours. Subsequently the samples of the broth from all the test tubes were plated to determine the presence or absence of viable cells. Results: The results showed that the control groups and that just washed in sterile water showed bacterial growth. Conclusion: The peracetic acid and glutaraldehyde was also effective for disinfection of alginate infected with S. aureus...

Biocompatibility studies of anionic collagen membranes with different degree of glutaraldehyde cross-linking

Goissis, G.; Junior, E. M.; Marcantonio, JAC; Lia, RCC; Cancian, DCJ; de Carvalho, M.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 27-34
ENG
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The work describes the biocompatibility and biodegradation studies of anionic collagen membranes casted form collagen gels collagen, that were selective hydrolyzed at the carboxyamide groups, as a function of the degree of cross-links induced by glutaraldehyde. Independently from the degree of cross-links, all membranes studied were characterized by a similar inflammatory response, inversely dependent on glutaraldehyde reaction time, that decreased from the time of the implant. Cell alterations, mineralization or contact necrosis were not observed in any of the membranes studied. Rates for membrane tissue biodegradation were directly related to glutaraldehyde reaction time, and ranged from 30 to periods longer than 60 days, associated with good biocompatibility. Although other properties must be considered, their use in the treatment of periodontal diseases, the biological behavior observed with the 8 h GA cross-linked membrane suggests that, anionic collagen membrane described in this work may be of potential use, not only in association with guided tissue regeneration technique for periodontal tissue reconstruction, but also in other collagen biomaterial applications where controlled biodegradability is required. (C) 1998 Published by Elsevier B.V. Ltd. All rights reserved.

Modification of glassy carbon electrodes with a poly-L-lysine/glutaraldehyde film

Pereira, F. C.; Bergamo, E. P.; Stradiotto, N. R.; Zanoni, Maria Valnice Boldrin; Fogg, A. G.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1439-1443
ENG
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A film of poly-L-lysine (PLL) adheres better to the surface of a glassy carbon electrode when the PLL is partially cross-linked by means of glutaraldehyde. A film composition of 97.5% PLL/2.5% glutaraldehyde gives good adhesion and retains the anionic exchange capability of the PLL. The performance of the film was tested with hexacyanoferrate(III) using electrochemical and nonelectrochemical accumulation.

Determination of iodide and idoxuridine at a glutaraldehyde-cross-linked poly-L-lysine modified glassy carbon electrode

Pereira, F. C.; Fogg, A. G.; Ugo, P.; Bergamo, E. P.; Stradiotto, N. R.; Zanoni, Maria Valnice Boldrin
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1309-1316
ENG
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The detection limit (about 0.017 mu g mL(-1)) for voltammetric determination of iodide (peak at +0.87 V vs. Ag/AgCl at pH 2) at a glutaraldehyde-cross-linked poly-L-lysine modified glassy carbon electrode involving oxidation to iodine was found to be several orders of magnitude lower than that for the voltammetric determination on a bare glassy carbon electrode. This method was applied successfully to the determination of iodide in two medicinal formulations. Idoxuridine was determined indirectly at the same electrode by accumulating it first at -0.8 V vs. Ag/AgCl. At this potential the C-I bond in the adsorbed idoxuridine is reduced giving iodide, which is then determined at the modified electrode. The method was successfully applied to the determination of idoxuridine in a urine sample.

Determination of salicylate in blood serum using an amperometric biosensor based on salicylate hydroxylase immobilized in a polypyrrole- glutaraldehyde matrix

Rover Júnior, Laércio; De Oliveira Neto, Graciliano; Roberto Fernandes, João; Tatsuo Kubota, Lauro
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 547-557
ENG
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The use of an amperometric biosensor for the salicylate determination in blood serum is described. The biosensor is based on salicylate hydroxylase (EC 1.14.13.1) electropolymerized onto a glassy carbon-working electrode with polypyrrole and glutaraldehyde, to improve the biosensor lifetime. The hexacyanoferrate (II) was also incorporated to work as a redox mediator to minimize possible interferences. The salicylate is enzymatically converted to catechol, which is monitored amperometrically by its electrooxidation at +0.170 V versus SCE (saturated calomel electrode). Salicylate determination was carried out maintaining the ratio between β-NADH and salicylate at 4:1 (30°C). The amperometric response of the biosensor was linearly proportional to the salicylate concentration between 2.3 x 10-6 and 1.4 x 10-5 mol l- 1, in 0.1 mol l-1 phosphate buffer (pH 7.8), containing 0.1 mol l-1 KCl and 5.0 x 10-4 mol l-1 Na2H2EDTA, as supporting electrolyte. The recovery studies, in the presence of several interfering compounds, showed recoveries between 96.4 and 104.8%. The useful lifetime of the biosensor in the concentration range evaluated was at least 40 days, in continuous use. Blood serum samples analyzed by this biosensor showed a good correlation compared to the spectrophotometric method (Trinder) used as reference...

Optimization of the immobilization of sweet potato amylase using glutaraldehyde-agarose support. Characterization of the immobilized enzyme

Tavano, Olga Luisa; Fernandez-Lafuente, Roberto; Goulart, Antonio José; Monti, Rubens
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1054-1058
ENG
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A simplified procedure for the preparation of immobilized beta-amylase using non-purified extract from fresh sweet potato tubers is established in this paper, using differently activated agarose supports. Beta-amylase glutaraldehyde derivative was the preparation with best features, presenting improved temperature and pH stability and activity. The possibility of reusing the amylase was also shown, when this immobilized enzyme was fully active for five cycles of use. However, immobilization decreased enzyme activity to around 15%. This seems to be mainly due to diffusion limitations of the starch inside the pores of the biocatalyst particles. A fifteen-fold increase in the Km was noticed, while the decrease of Vmax was only 30% (10.1 U mg-1 protein and 7.03 U mg-1 protein for free and immobilized preparations, respectively). © 2013 Elsevier Ltd.

Transdentinal cytotoxicity of carbodiimide (EDC) and glutaraldehyde on odontoblast-like cells

Scheffel, Débora Lopes Salles; Bianchi, Luciana; Soares, Diana Gabriela; Basso, Fernanda Gonçalves; Sabatini, Camila; Souza Costa, Carlos Alberto de; Pashley, David H.; Hebling, Josimeri
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 44-54
ENG
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Objective: To evaluate the transdentinal cytotoxicity of three different concentrations of carbodiimide (EDC) or 5% glutaraldehyde (GA) on MDPC-23 cells. Methods: Seventy 0.4-mm-thick dentin disks obtained from human molars were adapted to artificial pulp chambers. MDPC-23 cells were seeded on the pulpal surface of the disks. After 48 hours, the occlusal dentin was acid-etched and treated for 60 seconds with one of the following solutions (n=10): no treatment (negative control); 0.1 M, 0.3 M, or 0.5 M EDC; 5% GA; Sorensen buffer; or 29% hydrogen peroxide (positive control). Cell viability and morphology were assessed by methyltetrazolium assay and scanning electron microscopy (SEM), respectively. The eluates were collected after the treatments and applied on MDPC-23 seeded in a 24-well plate to analyze cell death, total protein (TP), and collagen production. The last two tests were performed 24 hours and seven days after the challenge. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results: EDC at all test concentrations did not reduce cell viability, while 5% GA did increase cell metabolism. Cell death by necrosis was not elicited by EDC or 5% GA. At the 24-hour period, 0.3 M and 0.5 M EDC reduced TP production by 18% and 36.8%...

Efeito da reticulação induzida pela transglutaminase e o glutaraldeido sobre as propriedades das microparticulas obtidas por coacervação complexa; Effect of transglutaminase and glutaraldehyde induced crosslinking on properties of microparticles obtained by complex coacervation

Fernando Tello Celis
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/02/2009 PT
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Micropartículas foram produzidas por coacervação complexa utilizando gelatina e goma arábica como materiais formadores de parede e uma mistura de oleoresina de páprica-óleo de soja (1:10) em quantidade que corresponde a 50% de massa dos materiais de parede. A ordem de produção das emulsões, gelatina/oleoresina de páprica-óleo de soja ou goma arábica/oleoresina de páprica-óleo de soja, a reticulação das micropartículas com transglutaminase (10 a 50U/g.ptn) ou com glutaraldeído (1mM/g.ptn) e a melhora de características funcionais em função desses fatores foram avaliadas. Foram avaliadas a capacidade de inchamento, resistência à solução de dodecil sulfato de sódio (SDS, 2 e 5%), à temperatura (65 e 97°C/15 min), valores de pH 1, 2 e 7 e resistência a condições simuladas do pH do estômago e intestino (temperatura e enzimas). Adicionalmente foi acompanhado o efeito dos tratamentos na liberação do recheio hidrofóbico em óleo de girassol. Microscopia ótica, eletrônica de varredura e espectrofotometria foram utilizadas para as avaliações de resistência e de liberação. As micropartículas apresentaram forma esférica e tamanho médio na faixa de 55-70mm, com o recheio distribuído de forma multinuclear e homogênea. As micropartículas resistiram...

Effect of freeze-drying on the mechanical, physical and morphological properties of glutaraldehyde-treated bovine pericardium: evaluation of freeze-dried treated bovine pericardium properties

BORGOGNONI, Camila F.; MAIZATO, Marina J. S.; LEIRNER, Adolfo A.; POLAKIEWICZ, Bronislaw; BEPPU, Marisa M.; HIGA, Olga Z.; PITOMBO, Ronaldo N. M.
Fonte: WICHTIG EDITORE Publicador: WICHTIG EDITORE
Tipo: Artigo de Revista Científica
ENG
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Purpose: Biomaterials have been widely used in the field of regenerative medicine. Bovine pericardium tissue has been successfully used as a bioprosthetic material in manufacturing heart valves, but studies concerning the tissue are ongoing in order to improve its storage, preservation and transportation. This article provides an overview of the characteristics of bovine pericardium tissue chemically treated after the freeze-drying process. These characteristics are essential to evaluate the changes or damage to the tissue during the process. Methods: The mechanical properties of the tissue were analyzed by three different methods due to its anisotropic characteristics. The physical properties were analyzed by a colorimetric method, while the morphological properties were evaluated by scanning electron microscopy (SEM). Results: The freeze-dried bovine pericardium showed no significant change in its mechanical properties. There was no significant change in the elasticity of the tissue (p > 0.05) and no color change. In addition, SEM analysis showed that the freeze-dried samples did not suffer structural collapse. Conclusions: It was concluded that glutaraldehyde-treated bovine pericardium tissue showed no significant change in its properties after the freeze-drying process.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The use of filter paper plasticized with polyvinyl alcohol-glutaraldehyde in ELISA

Barbosa,G.H.T.S.; Santana,E.M.; Almeida,A.M.P.; Araujo,A.M.; Fatibello-Filho,O.; Carvalho Jr.,L.B.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2000 EN
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F1-antigen purified from Yersinia pestis was covalently linked to 5-mm diameter filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde. These discs were used both for ELISA and dot-ELISA for the detection of anti-F1 IgG in rabbits. The best conditions were achieved using 1.25 µg of F1 antigen/disc, 3% w/v skim milk in PBS as blocking agent, anti-IgG peroxidase conjugate diluted 12,000 times, and serum from rabbits immunized or not against Y. pestis, diluted 6,400 times. The absorbance values obtained from the comparative study between this procedure and conventional ELISA were not significantly different but the low cost of the reagents employed in ELISA using the filter paper discs plasticized with polyvinyl alcohol-glutaraldehyde makes this method economically attractive.

Alquilação redutiva da quitosana a partir do glutaraldeído e 3-amino-1-pr; Reductive alkylation of chitosan by glutaraldehyde and 3-amino-1-propanol

Alves, Keila dos Santos
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Química; Físico-Química; Química Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Química; Físico-Química; Química
Tipo: Dissertação Formato: application/pdf
POR
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Chitosan derivatives were prepared by reductive alkylation using glutaraldehyde and 3-amino-1-propanol. The reducing agent used was the sodium borohydride. Tests of solubility, stability and viscosity were performed in order to evaluate these parameters effects in the reaction conditions (molar ratio of the reactants and presence of nitrogen in the reaction system). The molecular structure of commercial chitosan was determined by infrared (IR) and hydrogen nuclear magnetic resonance spectroscopy (1H NMR). The intrinsic viscosity and average molecular weight of the chitosan were determined by viscosimetry in 0.3 M acetic acid aqueous solution 0.2 M sodium acetate at 25 ºC. The derivatives of chitosan soluble in aqueous acidic medium were characterized by 1H NMR. The rheological behavior of the chitosan and of the derivative of chitosan (sample QV), which presented the largest viscosity, were studied as a function of polymer concentration, temperature and ionic strength of the medium. The results of characterization of the commercial chitosan (the degree of deacetylation obtained equal 78.45 %) used in this work confirmed a sample of low molar weight (Mv = 3.57 x 104 g/mol) and low viscosity (intrinsic viscosity = 213.56 mL/g). The chemical modification of the chitosan resulted in derivatives with thickening action. The spectra of 1H NMR of the soluble derivatives in acid aqueous medium suggested the presence of hydrophobic groups grafted into chitosan in function of the chemical modification. The solubility of the derivatives of chitosan in 0.25 M acetic acid aqueous solution decreased with increase of the molar ratio of the glutaraldehyde and 3-amino-1-propanol in relation to the chitosan. The presence of nitrogen and larger amount of reducing agent in reaction system contributed to the increase of the solubility...

DESINFECTANTES DE ALTO NIVEL ALTERNATIVOS AL GLUTARALDEHÍDO PARA PROCESAMIENTO DE ENDOSCOPIOS FLEXIBLES; HIGH-LEVEL DISINFECTANTS ALTERNATIVE TO GLUTARALDEHYDE FOR PROCESSING FLEXIBLE ENDOSCOPES; DESINFETANTES DE ALTO NÍVEL ALTERNATIVOS AO GLUTARALDEÍDO PARA PROCESSAMENTO DE ENDOSCÓPIOS FLEXÍVEIS

Psaltikidis, Eliane Molina; Hospital de Clínicas da Unicamp; Leichsenring, Mirtes Loeschner; Nakamura, Marlene Hitomi Yoshida; Bustorff-Silva, Joaquim Murray; Passeri, Luis Augusto; Venâncio, Sonia Isoyama
Fonte: Universidade Federal do Paraná Publicador: Universidade Federal do Paraná
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf; application/pdf
Publicado em 28/09/2014 POR; ENG
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Fundamentales en diversas especialidades médicas, los endoscopios flexibles son, normalmente, termosensibles, semicríticos y sometidos a la desinfección de alto nivel. El glutaraldehído es muy utilizado para esa finalidad, en razón de la gran compatibilidad y bajo custo, pero la tolerancia de microbacterias y el hecho de ser o no tóxico de modo ocupacional presionan por la adopción de germicidas alternativos. Fue realizada revisión sistemática con el objetivo de buscar evidencias sobre la efectividad, toxicidad y potenciales daños causados a los endoscopios por los germicidas alternativos al glutaraldehído, disponibles en el mercado brasileño. Fueron identificadas, en 13 bases electrónicas, 822 publicaciones, entre 2008 y 2013. De estas, fueron seleccionados 23 estudios, considerando la mejor cualidad de evidencia disponible. Las publicaciones apuntaron para la superioridad del ácido peracético y del ortoftalaldehído cuanto a la eficacia en la desinfección de alto nivel. Solamente el or toftalaldehído presentó evento adverso claramente relacionado a su utilización. No hay evidencias suficientes para afirmar que algun de estes germicidas presenta mayor potencial de daños a los equipos.; Endoscópios flexíveis são fundamentais em diversas especialidades médicas; em geral são termossensíveis...