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1.
Braz. j. oral sci ; 21: e220616, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1393329

RESUMO

The use of selective barriers as resorbable membranes has become a routine clinical procedure for guided bone regeneration. Therefore, the production of membranes with a low inflammatory potential during their resorption process has become the goal of a considerable number of researches. Aim: The purpose of the present study was to evaluate the biocompatibility of poly (L- lactic acid) (PLLA) and biocelulose membranes (BC) inserted in the subcutaneous tissue on the dorsum of rats. Methods: Fifteen animals underwent surgical procedures for the insertion of 4 types of membranes: COL (Collagen membrane) ­ Control Group; BC (Biocellulose membrane); BCAg (Biocellulose membrane impregnated with Silver); PLLA (Poly (L-lactic acid) membrane). All membrane types were inserted into each animal. Animals were euthanized after 3, 7, and 15 days of the surgical procedure. Descriptive histological analyses were carried out to investigate host tissue reaction to membrane presence by assessing the anti-inflammatory process composition associated with the membrane resorption and the presence of foreign-body reaction or encapsulation. Results: The BC membranes showed a higher degree of inflammation and poor pattern of integration with the surrounding tissues than the PLLA and COL membranes. Conclusion: The PLLA and COL membranes present better biocompatibility than the BC membranes


Assuntos
Animais , Ratos , Materiais Biocompatíveis/análise , Regeneração Óssea , Teste de Materiais , Ácido Láctico , Tela Subcutânea , Membranas , Celulose , Inflamação
2.
Rev. peru. med. exp. salud publica ; 39(3): 312-320, jul.-sep. 2022. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1410010

RESUMO

RESUMEN Objetivo. Desarrollar y evaluar un método de bajo costo basado en celulosa para la purificación rápida y amplificación directa de ADN de Bordetella pertussis de hisopados nasofaríngeos. Materiales y métodos. Se prepararon discos de celulosa y se evaluaron diferentes parámetros (buffers de lisis/lavado, número de discos y elución de ADN). El método se acopló a una amplificación directa por PCR en tiempo real (qPCR) y se estimó el rendimiento utilizando hisopados nasofaríngeos que fueron positivos (n=100) y negativos (n=50) para ADN B. pertussis por qPCR, comparado con el método basado en columnas de sílice. Se calculó el grado de concordancia, sensibilidad, especificidad, valor predictivo positivo (VPP) y valor predictivo negativo (VPN). Se evaluó la factibilidad del método rápido para ser acoplado a un ensayo colorimétrico de amplificación isotérmica mediada por lazo (LAMP). Resultados. El método rápido con un disco de celulosa y buffer de lisis y lavado conteniendo PVP-40 y Tween 20, respectivamente, mostró una mayor capacidad para purificar ADN amplificable de B. pertussis. El método tuvo una sensibilidad de 89,0% (IC95%, 80,2%-94,9%) y una especificidad de 98,5% (IC95%, 92,1%-100,0%), con un buen grado de concordancia (Kappa=0,867; IC95% 0,788 - 0,946), respecto al método referencial. Los VPP y VPN fueron 98,6% (IC95%, 92,7,2%-100,0%) y 88,2% (IC95%, 78,7%-94,4%), respectivamente. Se evidenció una amplificación exitosa por LAMP, y se obtuvieron resultados comparables con el método por columnas de sílice. Conclusión. El método desarrollado es simple, de bajo costo y libre de equipos para la obtención rápida (60 segundos) de ADN en el punto de atención, y puede ser implementado en diversas técnicas moleculares orientados al diagnóstico oportuno y al estudio epidemiológico de tos ferina.


ABSTRACT Objective. To develop and evaluate a low-cost cellulose-based method for rapid purification and direct amplification of Bordetella pertussis DNA from nasopharyngeal swabs. Materials and methods. We prepared cellulose discs and evaluated different parameters (lysis/wash buffers, number of discs and DNA elution). The method was coupled to a direct real-time PCR (qPCR) amplification and the performance was estimated using nasopharyngeal swabs that were positive (n=100) and negative (n=50) for B. pertussis DNA by qPCR, compared to the silica column-based method. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) and the degree of agreement. The feasibility of the rapid method to be coupled to a loop-mediated isothermal amplification colorimetric assay (LAMP) was evaluated. Results. The rapid method, with a cellulose disk and lysis and wash buffer containing PVP-40 and Tween 20, respectively, showed a greater capacity to purify amplifiable DNA from B. pertussis. The method had a sensitivity of 89.0% (95%CI: 80.2%-94.9%) and a specificity of 98.5% (95%CI: 92.1%-100.0%), with a good degree of agreement (Kappa=0.867; 95%CI: 0.788 - 0.946), compared to the reference method. The PPV and NPV were 98.6% (95%CI: 92.7.2%-100.0%) and 88.2% (95%CI: 78.7%-94.4%), respectively. Successful amplification by LAMP was evident, and comparable results were obtained with the silica column method. Conclusion. The developed method is simple, low-cost and equipment-free for rapid (60 seconds) DNA collection at the point of care, and can be implemented in various molecular techniques aimed at the timely diagnosis and epidemiological study of pertussis.


Assuntos
Humanos , Bordetella pertussis/genética , DNA Bacteriano/isolamento & purificação , Celulose , Reação em Cadeia da Polimerase em Tempo Real , Coqueluche/diagnóstico , Nasofaringe/microbiologia , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular
3.
Int. j. high dilution res ; 21(2): 5-5, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex - Homeopatia | ID: biblio-1396750

RESUMO

Highly diluted and succussed solutions (homeopathic potencies) have been shown to interact with a wide range of solvatochromic dyes based on changes in their UV-visible spectra. Studies so far have involved free dyes in solution, but there is a pressing need to find ways to investigate the potency-dye interaction using isolated dye molecules in order to ask more searching physico-chemical questions regarding the fundamental nature of potencies. Aims and Methods:The aims of the present study have been tolook for ways to covalently immobilizesolvatochromic dyes onto transparent cellulose films and hence be in a position to investigate dye-potency interactions without the complication of dye-dye interactions, including dye aggregation, which can occur with free dyes in solution. Results: to date a total of nine different dyes have been immobilised on cellulose films using epoxide activation of hydroxyl groups on the cellulose surface. Using this methodology studies have begun looking at the time course of potency action on one of these immobilised dyes, Brooker's merocyanine. Results show that the interaction ofArsenicum10M with this dye consists of three phases ­an initial growth phase, a sustained plateau of interaction and a final decline phase lasting several days.Conclusions: amethodology has been developed that successfully immobilises solvatochromic dyes onto transparent cellulose film. These films can then be used in a spectrophotometer to study at a much more detailed level how potencies interact with dyes compared with using free dyes in solution. Results indicate that the information gained in this way provides new insights regarding the fundamental nature of potencies. Specifically, studies using immobilised Brooker's merocyanine with Arsenicum10M reveal that the lifetime of the potency is much longer than expected and that its action consists of three distinct phases, suggesting a resonant interaction with the dye.


Assuntos
Celulose , Potência
4.
Ciênc. rural (Online) ; 52(4): e20210357, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339676

RESUMO

Crop residues decomposition are controlled by chemical tissue components. This study evaluated changes on plant tissue components, separated by the Van Soest partitioning method, during cover crop decomposition. The Van Soest soluble fraction was the first to be released from the crop residues, followed by cellulose and hemicellulose. Lignin was the crop residue component that suffered the least degradation, and for certain crop residue types, lignin degradation was not detected. The degradation of the main components of crop residues (soluble fraction, cellulose, hemicellulose and lignin) is determined by the chemical and structural composition of each fraction.


A decomposição de resíduos culturais é controlada pela composição química do tecido vegetal. O objetivo deste estudo foi avaliar as alterações que ocorrem nos componentes do tecido vegetal, separados pelo fracionamento de Van Soest, durante a decomposição de plantas de cobertura. A fração solúvel foi a primeira a ser liberada dos resíduos culturais, seguida pela celulose e hemicelulose. A lignina foi o componente dos resíduos culturais de menor degradação, sendo que em alguns resíduos culturais não foi possível detectar a degradação deste componente. A degradação dos principais componentes dos resíduos culturais (fração solúvel, celulose, hemicelulose e lignina) é determinada pela composição química e estrutural de cada uma destas frações.


Assuntos
Resíduos/análise , Madeira/química , Celulose/química , Lignina/química
5.
Braz. J. Pharm. Sci. (Online) ; 58: e21044, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420468

RESUMO

Abstract The current investigation was used to improve the rate of dissolution of an anti-diarrheal drug i.e., racecadotril (RT) at low pH conditions (i.e., in the stomach) by reducing the water secretion and electrolyte in to the intestine by liquisolid tablets. Different formulations (liquisolid) were prepared using Avicel PH 102 as a carrier. Aerosil 200 as a coating material and sodium starch glycolate used as a disintegrant. Polyethylene glycol 200 was used as a non-volatile vehicle to dissolve the drug. FTIR, DSC, XRD and dissolution studies were conducted to characterise liquisolid tablets. Characterisation studies indicated that no interactions between carrier and drug. Solid state characterization had shown a reduction in crystallinity that further supports increment in solubility and dissolution. The optimised formulation showed a significant increase in dissolution i.e., 99.54±0.62% in 30 min compared to directly compressible tablets (38.47±0.26%). The % dissolution efficiency of racecadotril liquisolid tablets 76.86% compared to marketed tablet (27.56%) and conventional direct compression tablet (17.11%). Significant reduction in mean dissolution time of racecadotril from liquisolid tablets (6.84 min) compared to direct compression tablet (44.57 min), indicating faster release of drug and faster onset of action. Formulation of liquisolid tablets could enhance solubility, dissolution and bioavailability of racecadotril


Assuntos
Dissolução , Antidiarreicos/análise , Estômago/anormalidades , Preparações Farmacêuticas/análise , Celulose/agonistas , Intestinos/anormalidades
6.
Electron. j. biotechnol ; 50: 29-36, Mar. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1292313

RESUMO

BACKGROUND: Lignocellulose is considered a renewable organic material, but the industrial production of biofuel from lignocellulose is challenging because of the lack of highly active hydrolytic enzymes. The guts of herbivores contain many symbiotic microorganisms that have evolved to hydrolyze plant lignocellulose. Chinese bamboo rats mainly consume high-fiber foods, indicating that some members of the intestinal tract microbiota digest lignocellulose, providing these rats with the energy required for growth. RESULTS: Here, we used metagenomics to analyze the diversity and functions of the gut microbiota in Chinese bamboo rats. We identified abundant populations of lignocellulose-degrading bacteria, whose main functions involved carbohydrate, amino acid, and nucleic acid metabolism. We also found 587 carbohydrate-active enzyme genes belonging to different families, including 7 carbohydrate esterase families and 21 glycoside hydrolase families. The glycoside hydrolase 3, glycoside hydrolase 1, glycoside hydrolase 43, carbohydrate esterase 4, carbohydrate esterase 1, and carbohydrate esterase 3 families demonstrated outstanding performance. CONCLUSIONS: The microbes and enzymes identified in our study expand the existing arsenal of proficient degraders and enzymes for lignocellulosic biofuel production. This study also describes a powerful approach for targeting gut microbes and enzymes in numerous industries.


Assuntos
Animais , Ratos , Ceco/enzimologia , Enzimas/metabolismo , Lignina/metabolismo , Ceco/microbiologia , Celulose/metabolismo , Bacteroidetes , Biocombustíveis , Metagenômica , Firmicutes , Microbioma Gastrointestinal
7.
ABCD (São Paulo, Impr.) ; 34(2): e1586, 2021. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1345001

RESUMO

ABSTRACT Background: The treatment of 3rd degree burns represents a major medical challenge. Pinus vegetable cellulose is a biomaterial with characteristic similar to bacterial cellulose. Aim: To evaluate the safety of cellulose membrane (Pinus sp) in the treatment of 3rd burns in rats and to compare its effectiveness with the bacterial membrane already on the market. Method: Thirty-three Wistar rats were beaten with a 3rd degree burn on back skin by applying water at 98º C for 30 s. Then, they were divided into three groups (n=11): group 1 - simple dressing with gauze; group 2 - dressing with bacterial cellulose membrane; and group 3 - dressing with vegetable cellulose membrane. The animals were maintained for 15 days to check the general clinical status, macroscopic aspect, contraction of the wounds and microscopic analysis for the degree of healing and collagenization. Results: They were clinically well during the experiment. During the removal of the dressing, there was bleeding in the wound of the control group, unlike the groups treated with cellulose membranes, which protected the bed from injury. The macroscopic evaluation showed a greater contraction of the wounds treated with the membranes in relation to the control. A microscopic analysis revealed that most of the wounds were in advanced healing degree with predominance of mature collagen in all groups. Conclusion: Pinus sp cellulose membrane showed efficacy similar to that of the bacterial membrane in the treatment of 3rd degree burns.


RESUMO Racional: O tratamento das queimaduras de 3˚ grau representa grande desafio na área médica. A celulose vegetal de pinus é biomaterial com características semelhantes às da celulose bacteriana. Objetivo: Avaliar a segurança da membrana de celulose vegetal (Pinus sp) no tratamento de queimaduras de terceiro grau em ratos e comparar sua eficácia com a da membrana bacteriana já comercializada. Método: Trinta e três ratos Wistar foram submetidos à queimadura de 3º grau na pele do dorso mediante aplicação de água a 98º C durante 30 s. Em seguida, foram distribuídos em três grupos (n=11): grupo 1 - curativo simples com gaze; grupo 2 - curativo com membrana de celulose bacteriana; e grupo 3 - curativo com membrana de celulose vegetal . Os animais foram avaliados durante 15 dias para verificar o estado clínico geral, aspecto macroscópico, contração das feridas e análise microscópica pelo grau de cicatrização e colagenizacao. Resultados: Permaneceram clinicamente bem durante o experimento. Durante a retirada do curativo houve sangramento na ferida do grupo controle, diferentemente dos grupos tratados com as membranas de celulose, que protegeram o leito da lesão. A análise microscópica mostrou que a maioria das feridas apresentava-se em grau avançado de cicatrização, com predomínio de colágeno maduro em todos os grupos. Houve maior contração das feridas tratadas com as membranas em relação ao grupo controle. Conclus ão: A membrana de celulose de Pinus sp apresentou eficácia semelhante à da membrana bacteriana no tratamento de queimaduras de 3˚ grau.


Assuntos
Animais , Ratos , Queimaduras/terapia , Síndrome de Imunodeficiência Adquirida , Nanofibras , Bandagens , Verduras , Celulose , Ratos Wistar
8.
Rev. bras. oftalmol ; 80(4): e0018, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1288632

RESUMO

ABSTRACT Objective: To describe ocular surface findings in impression cytology obtained from healthy rabbit conjunctiva treated with interferon alpha-2b eyedrop, and compare them to findings after use of mitomycin C 0.02%. Methods: An experimental study using a rabbit model was performed between September 2013 and October 2014 at the Faculdade de Medicina de Marília, Universidade Federal de São Paulo, Clínica de Olhos Moacir Cunha. Thirty New Zealand white rabbits were divided into 6 groups and received interferon alpha-2b or mitomycin C 0.02%. Impression cytology (IC) was performed prior to topical applications and at15, 30 and 60 days of use. The following variables were analyzed in impression cytology: goblet cells, cellularity, cell-to-cell adhesion, nucleus/cytoplasm ratio, nuclear chromatin, inflammatory cells keratinization, and cytomegaly. Results: The major findings in impression cytology after us of interferon alpha-2b included loss of goblet cells (50.8%), reduced cell-to-cell adhesion (26.2%), abnormal nucleus/cytoplasm ratio (20%) and reduced cellularity (15.4%). After use of mitomycin C 0.02%, the most common changes included loss of goblet cells (46.2%), abnormal nucleus/cytoplasm ratio (25.6%), less cell-to-cell adhesion (23.1%), and reduced cellularity (20.5%). There were no significant differences in any variable when comparing impression cytology after interferon alpha-2b and after mitomycin C 0.02%. Goblet cell loss was more pronounced at days 30 and 60, as compared to impression cytology at day 15 for both drugs. Conclusion: The loss of goblet cells, reduced cell-to-cell adhesion and cellularity, along with abnormal nucleus/cytoplasm ratio were the most common findings in impression cytology after use of interferon alpha-2b. These findings are similar to those described for use of mitomycin C 0.02%. ..


RESUMO Objetivo: Descrever os achados em citologia de impressão de conjuntiva sadia de coelho submetida ao uso de colírio de interferon alfa-2b e compará-los ao que foi encontrado após uso da mitomicina C 0,02%. Métodos: Estudo experimental realizado em modelo animal no período entre setembro de 2013 e outubro de 2014 nas dependências da Faculdade de Medicina de Marília, da Universidade Federal de São Paulo e da Clínica de Olhos Moacir Cunha. Trinta coelhos albinos da raça Nova Zelândia foram divididos em seis grupos e receberam interferon alfa-2b ou mitomicina C. A citologia de impressão foi realizada antes do início dos colírios e após 15, 30, 60 dias de seu uso. As seguintes variáveis foram analisadas na citologia de impressão: células caliciformes, celularidade, adesão intercelular, razão núcleo/citoplasma, cromatina, células inflamatórias, queratinização e citomegalia. Resultados: Os principais achados na citologia de impressão após o uso do interferon alfa-2b foram a redução de células caliciformes (50,8%), a diminuição da adesão intercelular (26,2%), a alteração da razão N/C (20%) e a redução da celularidade (15,4%). Após o uso da mitomicina C 0,02%, foram mais frequentes a redução das células caliciformes (46,2%), a alteração da razão N/C (25,6%), a adesão intercelular (23,1%) e a redução da celularidade (20,5%). Não houve diferença estatisticamente significante para nenhuma das variáveis estudas quando se compararam as citologias de impressão após interferon alfa-2b com as citologias de impressão após mitomicina C 0,02%. Independentemente da substância utilizada, as citologias colhidas 30 e 60 dias após início das drogas apresentaram maior redução de células caliciformes quando comparadas com as citologias de impressão colhidas após 15 dias. Conclusão: A redução das células caliciformes, a diminuição da adesão intercelular, a alteração da razão N/C e a diminuição da celularidade foram as alterações mais frequentes na citologia de impressão colhida após o uso de interferon alfa-2b. Os achados em citologias de impressão após o uso de interferon alfa-2b são semelhantes àqueles encontrados após o uso da mitomicina C 0,02%.


Assuntos
Animais , Coelhos , Mitomicina/farmacologia , Túnica Conjuntiva/citologia , Córnea/citologia , Interferon alfa-2/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Celulose , Técnicas Citológicas , Mitomicina/uso terapêutico , Túnica Conjuntiva/efeitos dos fármacos , Túnica Conjuntiva/ultraestrutura , Neoplasias da Túnica Conjuntiva/tratamento farmacológico , Técnicas de Cultura de Células , Córnea/efeitos dos fármacos , Córnea/ultraestrutura , Citodiagnóstico/métodos , Interferon alfa-2/uso terapêutico , Filtros Microporos
9.
Braz. j. otorhinolaryngol. (Impr.) ; 86(6): 727-733, Nov.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1142607

RESUMO

Abstract Introduction: Perforation of the tympanic membrane is a reasonably frequent diagnosis in otorhinolaryngologists' offices. The expectant management is to wait for spontaneous healing, which usually occurs in almost all cases in a few weeks. However, while waiting for healing to be completed, the patients may experience uncomfortable symptoms. Although some research suggests the use of various materials to aid in the recovery of the tympanic membrane, none presented robust evidence of improvement in the cicatricial process. Nevertheless, the occlusion of the perforation with some material of specific texture and resistance can alleviate the patients' symptoms and accelerate the healing process. Objective: To evaluate the clinical (symptomatic and functional) improvement after the placement of bacterial cellulose film (Bionext®) on tympanic membrane perforations (traumatic). Methods: We evaluated 24 patients, victims of traumatic perforations of the tympanic membrane, who were evaluated in the Otorhinolaryngology Emergency Room. Following otoscopy and audiometric examination was performed, before and after the use of cellulose film occluding the tympanic membrane perforation. Results: Twenty-four patients were included, whose degree of overall discomfort caused by the tympanic membrane perforation and the presence of symptoms of autophonia, ear fullness and tinnitus were investigated. The mean score attributed to the overall annoyance caused by tympanic membrane perforation was 7.79, decreasing to a mean value of 2.25 after the film application. Symptom evaluation also showed improvement after using the film: autophonia decreased from a mean value of 6.25 to 2.08, tinnitus from 7 to 1.92 and ear fullness from 7.29 to 1.96. The auditory analysis showed mean threshold values still within the normal range at low and medium frequencies, with slight hearing loss at acute frequencies, but with significant improvement at all frequencies, with the exception of 8000 Hz, after film use. Conclusion: The use of bacterial cellulose film fragment on traumatic perforations of the tympanic membrane promoted immediate functional and symptomatic recovery in the assessed patients.


Resumo Introdução: A perfuração da membrana timpânica é uma condição clínica relativamente frequente em consultórios de otorrinolaringologistas. A conduta é quase sempre expectante, aguardando cicatrização espontânea, que costuma ocorrer na quase totalidade dos casos em algumas semanas. No entanto, enquanto não se completa, os pacientes mantêm sintomas desconfortáveis. Embora algumas pesquisas sugiram o uso de materiais diversos para auxiliar na recuperação da membrana timpânica, nenhuma apresentou evidência substancial de melhoria no processo cicatricial. Por outro lado, a oclusão da perfuração com alguns materiais de textura e resistência específicas poderia aliviar os sintomas dos pacientes durante o processo cicatricial. Objetivo: Avaliar a melhoria clínica (sintomática e funcional) após a colocação de película de celulose bacteriana (Bionext®) sobre a perfuração da membrana timpânica (traumática). Método: Foram avaliados pacientes com perfurações traumáticas da membrana timpânica que deram entrada no pronto-socorro de otorrinolaringologia. Eles foram avaliados em relação a suas queixas e exame audiométrico, antes e após a aplicação de película de celulose que oclui a perfuração da membrana timpânica. Resultados: Foram incluídos 24 pacientes, nos quais foram pesquisados o grau de incômodo global causado pela perfuração da membrana timpânica e a presença de sintomas de autofonia, plenitude auricular e tinnitus. A média da nota atribuída ao incômodo global causado pela perfuração foi de 7,79; caiu para valor médio de 2,25 após a aplicação da película. A avaliação dos sintomas também apresentou melhoria após uso da película, autofonia caiu de valor médio de 6,25 para 2,08; zumbido de 7 para 1,92 e plenitude auricular de 7,29 para 1,96. A análise auditiva apresentou um valor médio de limiares ainda dentro da normalidade em frequências baixas e médias, com perda de audição leve em frequências agudas, porém com melhoria significante em todas as frequências, com exceção de 8000 Hz, após a colocação da película. Conclusão: A aplicação de fragmento de película de celulose bacteriana sobre perfurações traumáticas da membrana timpânica promoveu recuperação funcional e sintomática imediata nos pacientes estudados.


Assuntos
Humanos , Membrana Timpânica , Audiometria , Celulose , Perfuração da Membrana Timpânica/etiologia , Perfuração da Membrana Timpânica/terapia , Otoscopia
10.
Rev. enferm. UERJ ; 28: e51476, jan.-dez. 2020.
Artigo em Inglês, Português | BDENF - Enfermagem, LILACS | ID: biblio-1119621

RESUMO

Objetivo: desenvolver um modelo de máscara de tecido, com aplicação do elemento filtrante em celulose, para fins de utilização como barreira física segura para aerossóis, como estratégia de resposta emergencial à pandemia provocada pelo SARS-CoV-2. Método: pesquisa laboratorial realizada por meio de protótipos, testagens empíricas e análises e discussões junto a expertises. Resultados: a condução da pesquisa demonstrou que os aerossóis são retidos pela barreira física de celulose introduzida à estrutura das máscaras, o que motivou a segunda fase do estudo em unidade da Rede Brasileira de Laboratórios Analíticos de Saúde sobre a eficácia desses materiais. Conclusão: a confecção de máscaras de tecido é um fenômeno mundial importante e urgente frente à pandemia da COVID-19. Em função da crise de abastecimento e dos parâmetros ressaltados neste estudo, acredita-se que o uso desse equipamento possa ser estendido a setores não críticos de unidades de saúde, além da população em geral.


Objective: to develop a model of fabric mask, with the application of a cellulose filter element, for use as a safe physical barrier for aerosols, as an emergency response strategy for the SARS-CoV-2 pandemic. Method: laboratory research carried out by means of prototypes, empirical tests and analyses, and discussions with experts. Results: the research demonstrated that aerosols are retained by the physical cellulose barrier introduced into the structure of the masks, which motivated the second phase of the study into the effectiveness of these materials at a unit of the Brazilian Analytical Health Laboratories Network. Conclusion: the making of fabric masks is an important and urgent worldwide phenomenon in tackling the COVID-19 pandemic. In view of the supply crisis and the parameters highlighted in this study, it is believed that the use of this equipment can be extended to non-critical sectors of health units, as well as to the general population.


Objetivo: desarrollar un modelo de mascarilla de tela, con la aplicación de un elemento filtrante de celulosa, para su uso como barrera física segura para aerosoles, como estrategia de respuesta de emergencia para la pandemia SARS-CoV-2. Método: investigación de laboratorio realizada mediante prototipos, pruebas y análisis empíricos y discusiones con expertos. Resultados: la investigación demostró que los aerosoles son retenidos por la barrera física de celulosa introducida en la estructura de las máscaras, lo que motivó la segunda fase del estudio sobre la efectividad de estos materiales en una unidad de la Red Brasileña de Laboratorios Analíticos de Salud. Conclusión: la fabricación de máscaras de tela es un fenómeno mundial importante y urgente para hacer frente a la pandemia de COVID-19. Ante la crisis de oferta y los parámetros resaltados en este estudio, se cree que el uso de este equipamiento puede extenderse a sectores no críticos de las unidades de salud, así como a la población en general.


Assuntos
Humanos , Infecções por Coronavirus/prevenção & controle , Equipamento de Proteção Individual/normas , Betacoronavirus , Máscaras/normas , Teste de Materiais , Brasil , Celulose , Filtros , Capacidade de Resposta ante Emergências , Pandemias/prevenção & controle
11.
Rev. argent. microbiol ; 52(1): 4-12, mar. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1155677

RESUMO

Abstract Currently, the valorization of agroindustrial waste is of great interest. Moringa oleifera is a multipurpose tree whose softwood residues could be used as raw material for low-cost cellulase production. The aim of this study was to isolate, identify, and characterize microorganisms with cellulolytic activity in different carbon sources. We isolated and puri-fied 42 microorganisms from M. oleifera biomass. Fungi presenting the largest hydrolytic halos in carboxymethylcellulose as a substrate were molecularly identified as Penicillium funiculosum (FG1), Fusarium verticillioides (FG3) and Cladosporium cladosporioides (FC2). The ability of these fungal strains to break down cellulose was assessed in a submerged fermentation using either amorphous CMC or crystalline form (Avicel). P. funiculosum and C. cladosporioides displayed similar endoglucanase (606 U/l) and exoglucanase (205 U/l) activities in the Avicel-containing medium, whereas F. verticillioides showed the highest level of p-glucosidase activity (664 U/l) in the carboxymethylcellulose medium. In addition, the effect of three culture media (A, B, and C) on cellulase production was evaluated in P. funiculosum using moringa straw as a carbon source. The results showed a volumetric productivity improvement of cellulases that was 2.77-, 8.26-, and 2.30-fold higher for endoglucanase, exoglucanase and p-glucosidase, respectively when medium C containing moringa straw was used as a carbon source. The enzymatic extracts produced by these fungi have biotechnological potential especially for second-generation bioethanol production (2G) from moringa straw. This is the first report on the use of M. oleifera biomass to induce the production of various cellulases in P. funiculosum. © 2019 Asociación Argentina de Microbiología. Published by Elsevier Espana, S.L.U. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/).


Resumen Actualmente, la valorización de los residuos agroindustriales es de gran interés. En este trabajo se emplearon residuos de madera blanda de Moringa oleifera para la producción de celulasas de bajo costo. El objetivo fue aislar, identificar y caracterizar microorganismos con actividad celulolítica en diferentes fuentes de carbono. A partir de la biomasa de M. oleifera, se aislaron e identificaron 42 microorganismos productores de celulasas. Los hongos que presentaron los mayores halos de hidrólisis en carboximetilcelulosa como sustrato fueron identificados molecularmente como Penicillium funiculosum (FG1), Fusarium verticillioides (FG3) y Cladosporium cladosporioides (FC2). Mediante fermentación sumergida, se evaluó la capacidad de estas cepas en la producción de celulasas utilizando celulosa cristalina (Avicel) y amorfa (CMC) como fuentes de carbono. P. funiculosum y C. cladosporioides presentaron las mayores actividades de endoglucanasa (606 U/l) y exoglucanasa (205 U/l) en medio Avicel, mientras que F. verticillioides mostró la mayor actividad de p-glucosidasa (664 U/l) en medio CMC. Además, se evaluó el efecto de tres medios de cultivo (A, B y C) sobre la producción de celulasas en P. funiculosum empleando residuos de moringa como fuente de carbono. Los resultados mostraron que en el medio C, la productividad volumétrica de celulasas se incrementó en 2,77; 8,26 y 2,30 veces para las actividades de endoglucanasa, exoglucanasa y p-glucosidasa, respectivamente. Los extractos enzimáticos producidos tienen gran potencial para su utilización biotecnológica, especialmente en la sacarificación de residuos de moringa y la producción de bioetanol de segunda generación. Este es el primer estudio del uso de la biomasa de M. oleifera para inducir la producción de diversas celulasas en P. funiculosum.


Assuntos
Celulase/fisiologia , Celulose/metabolismo , Cladosporium/enzimologia , Moringa oleifera/enzimologia , Talaromyces/enzimologia , Fusarium/enzimologia
12.
ABCD (São Paulo, Impr.) ; 33(2): e1533, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1130522

RESUMO

ABSTRACT Background: Despite all the advances in medicine and the wide variety of dressings available, the treatment of burn wounds still represents an important medical challenge. The pinus cellulose membrane dressing is a biomaterial with characteristics similar to those of bacterial cellulose, but with lower cost. Aim: To evaluate the efficacy of pinus nanocellulose membrane on healing of deep second degree burns in rats and compare with Membracel®. Method: Thirty male Wistar rats were submitted to deep second degree burn in dorse, with boiling water at 97o C for 20 s, generating a 314 mm² area wound. The animals were distributed in three dressing groups (n=10): group 1 - simple gauze; group 2 - bacterial cellulose membrane (Membracel®); and group 3 - pinus cellulose membrane. They were evaluated for 20 days to verify clinical condition, macro and microscopic appearance and wound contraction. Results: All of them remained clinically well with no differences in weight. Crusts were observed in group 1, and none in groups 2 and 3. Regarding to scar contraction, groups 2 and 3 were similar, better than group 1. Microscopic analysis showed predominance of advanced healing degree in groups 1 and 3, and initial in group 2. Mature collagen was predominant in all groups. Conclusion: The pinus nanocellulose membrane is effective in the treatment of experimental second degree burn in rats and its effectiveness is similar to that of the bacterial nanocellular membrane.


RESUMO Racional: Apesar de todos os avanços da medicina e da grande variedade de curativos disponíveis, o tratamento das queimaduras ainda representa importante desafio médico. O curativo de membrana de celulose de pinus é biomaterial com características semelhantes à de celulose bacteriana, mas de menor custo. Objetivo: Avaliar a eficácia da membrana de nanocelulose de pinus na cicatrização de queimaduras profundas de segundo grau em ratos e comparar com a Membracel®. Método: Trinta ratos Wistar machos foram submetidos à queimadura profunda de segundo grau em dorso, com água fervente a 97o C por 20 s, gerando lesão de 314 mm². Os animais foram distribuídos em três grupos de curativos (n = 10): grupo 1 - gaze simples; grupo 2 - membrana de celulose bacteriana (Membracel®); e grupo 3 - membrana de celulose de pinus. Eles foram avaliados por 20 dias para verificar o quadro clínico, aspecto macro e microscópico e a contração da ferida. Resultados: Todos permaneceram clinicamente bem, sem diferenças de peso. Crostas foram observadas no grupo 1 e nenhuma nos grupos 2 e 3. Em relação à contração da cicatriz, os grupos 2 e 3 foram semelhantes, melhores que o grupo 1. A análise microscópica mostrou predomínio de grau de cicatrização avançado nos grupos 1 e 3, e inicial no grupo 2. O colágeno maduro foi predominante em todos os grupos. Conclusão: A membrana de nanocelulose de pinus é eficaz no tratamento de queimaduras experimentais de segundo grau em ratos e sua eficácia é semelhante à da membrana nanocelular bacteriana.


Assuntos
Animais , Masculino , Ratos , Bandagens , Cicatrização , Queimaduras/terapia , Celulose/farmacologia , Pinus/química , Colágeno , Ratos Wistar
13.
Braz. J. Pharm. Sci. (Online) ; 56: e17797, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132045

RESUMO

Oral fast-dispersible film was prepared by utlizing donepezil hydrochloride (drug) and various cellulose derivatives such as hydroxypropyl methyl cellulose (hypermellose) (HPMC), microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) to treat Alzheimer's disease. NCC was synthesized by ultra-sonication method using MCC and this was converted to thinfilm formulation (NCC-F) using solvent casting technique. The interaction between the polymer and the drug was investigated by spectral analysis such as UV, FTIR, and 1H- NMR. FTIR confirmed that the compatibility of drug and polymer in ODF formulation. NCC-F has shown an average surface roughness of 77.04 nm from AFM and the average particle size of 300 nm from SEM analysis. Nano sized particle of NCC-F leads faster in vitro dissolution rate (94.53%) when compared with MCC-F and F3 formulation. Animal model (in vivo) studies of NCC-F formulation has reached peak plasma concentration (Cmax) up to 19.018 ng/mL in the span of (tmax) 4 h with greater relative bioavailability of 143.1%. These results suggested that high surface roughness with nanosized NCC-F formulation attained extended drug availability up to (t1/2) 70 h.


Assuntos
Animais , Masculino , Feminino , Ratos , Técnicas In Vitro/métodos , Dissolução/classificação , Donepezila/agonistas , Sonicação/métodos , Preparações Farmacêuticas/análise , Celulose , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Modelos Animais , Doença de Alzheimer/patologia
14.
Braz. J. Pharm. Sci. (Online) ; 56: e18660, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132061

RESUMO

The effect of drying method, a process variable, on the powder and compaction properties of microcrystalline cellulose (MCC) obtained from the partial acid hydrolysis of bleached alpha (α) cellulose content of matured linters of Gossypium herbaceum (GH) was investigated. A portion of the wet MCC obtained was fluid bed dried at 60 ± 1 ºC, inlet air of 30 m3 min-1 for 3 h (coded MCC-GossF). The second portion was lyophilized at - 45 ± 2 ºC for 6 h (coded MCC-GossL). The physicochemical, scanning electron micrographs, X ray diffraction patterns and micromeritic properties of the derived MCCs were determined using standard methods. The cohesiveness and compactibility of the powders were investigated using Kawakita model while the deformation and compressibility pattern were determined using Heckel model. Avicel® PH 102 (AV-102) was used as comparing standard. Ash values of < 2%, pH (6.54 ± 0.23 to 6.58 ± 0.08), degree of polymerization, DP (231.50) was obtained. MCC-GossF had higher moisture content, swellability, better flow indices, and lesser porosity than MCC-GossL. Kawakita model demonstrated good consolidation and compactibility for both powders. Compacts of MCC-GossL were significantly (p < 0.05) harder than those of MCC-GossF. Heckel analysis demonstrated good compressibility and deformation pattern that was comparable with AV-102. Compacts of MCC-GossL had better mechanical and tablet compression properties than MCC-GossF


Assuntos
Pós , Cinzas/efeitos adversos , Celulose/classificação , Gossypium herbaceum/análise , Baías/análise , Ar , Concentração de Íons de Hidrogênio , Hidrólise , Métodos
15.
Electron. j. biotechnol ; 42: 16-22, Nov. 2019. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1087350

RESUMO

Background: Fuels and chemicals from renewable feedstocks have a growing demand, and acetone, butanol and ethanol (ABE) are some relevant examples. These molecules can be produced by the bacterial fermentation process using hydrolysates generated from lignocellulosic biomass as sugarcane bagasse, one of the most abundant sources of lignocellulosic biomass in Brazil. It originates as a residue in mills and distilleries in the production of sugar and ethanol. Results: In the present work, two strategies to generate hydrolysates of sugarcane bagasse were adopted. The fermentation of the first hydrolysate by Clostridium acetobutylicum DSM 6228 resulted in final concentrations of butanol, acetone and ethanol of 6.4, 4.5 and 0.6 g/L, respectively. On the other hand, the second hydrolysate presented better results (averages of 9.1, 5.5 and 0.8 g/L, respectively), even without the need for nutrient supplementation, since key elements were already present in the medium. The productivity (QP) and yield (YP/S) of the solvents with second hydrolysate were 0.5 g/L•h-1 and 0.4 g/g, respectively. Conclusions: The results described herein open new perspectives for the production of important molecules from residual lignocellulosic biomass for the fuel and chemical industries within the context of second-generation biorefinery.


Assuntos
Acetona/metabolismo , Celulose/metabolismo , Saccharum/metabolismo , Etanol/metabolismo , Butanóis/metabolismo , Brasil , Celulose/química , Saccharum/química , Clostridium acetobutylicum/metabolismo , Biocombustíveis , Fermentação
16.
Prensa méd. argent ; 105(9 especial): 521-525, oct 2019. tab
Artigo em Inglês | LILACS, BINACIS | ID: biblio-1046371

RESUMO

Over the last decade, the interest in using bacterial cellulose in medicine has increased. The article publishes the data about the efficiency of healing burn wounds in rabbits in experimental conditions with the use of the DermaRM wound dressing, compared to the traditionally used Panthenol ointment and the Branolind N salve dressing


Assuntos
Animais , Coelhos , Pomadas/uso terapêutico , Bandagens , Queimaduras/terapia , Celulose/uso terapêutico , Resultado do Tratamento , Tempo para o Tratamento
17.
Electron. j. biotechnol ; 41: 30-36, sept. 2019. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1053564

RESUMO

Background: Yarrowia lipolytica is a nonconventional, dimorphic yeast with multiple biotechnological applications. Considering the size of Y. lipolytica cells and a plethora of its morphological forms (spherical cells or hyphae and pseudohyphae), it is highly difficult to select a suitable carrier for this useful microorganism. Bacterial cellulose (BC) is currently considered one of the most promising immobilization carriers. In the current study, the usefulness of oil- and emulsion-modified BCs as a carrier for Y. lipolytica immobilization was investigated. Static and agitated cultures were conducted in media supplemented with oil or emulsion to improve carrier porosity. Results: It was found that the application of oil- and emulsion-modified BCs correlated with significantly higher efficiency of Y. lipolytica immobilization and hence higher yield than the yield achieved with an unmodified carrier. Increased efficiency of immobilization correlated with BC porosity-related parameters, which, in turn, depended on the size of oil droplets introduced into the culture medium. Moreover, changes in porosity-related parameters caused by the addition of oil or emulsion to the medium were observed when the cultures were conducted only under static conditions and not under agitated conditions. Conclusion: The application of oil- and emulsion-modified BCs as carriers significantly increased the efficiency of Y. lipolytica immobilization as compared to unmodified BC. The addition of oil or emulsion to the culture medium can be a simple but effective method to modify the porosity of BC-based carriers.


Assuntos
Celulose/metabolismo , Yarrowia/metabolismo , Imobilização , Polímeros , Leveduras , Biotecnologia , Óleos de Plantas , Porosidade , Yarrowia/química , Nanoestruturas , Emulsões
18.
Electron. j. biotechnol ; 41: 95-99, sept. 2019. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1087252

RESUMO

Background: Pretreatment is the critically important step for the production of ethanol from lignocelluloses. In this study, hardwood birch (Betula pendula) and softwood spruce (Norway spruce) woods were pretreated with a newly synthesized morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]), followed by enzymatic hydrolysis and fermentation to ethanol. Results: [HMMorph][Cl] was synthesized using inexpensive raw materials, i.e., hydrochloric acid and N-methyl morpholine, following a simple process. The influence of pretreatment time (2, 3, 5, and 8 h) and temperature (120 and 140°C) in terms of hydrolysis efficiency was investigated. Glucose yields from enzymatic hydrolysis were improved from 13.7% to 45.7% and 12.9% to 51.8% after pretreatment of birch and spruce woods, respectively, under optimum pretreatment conditions (i.e., at 140°C for 3 h) as compared to those from pristine woods. Moreover, the yields of ethanol production from birch and spruce were increased to 34.8% and 44.2%, respectively, while the yields were negligible for untreated woods. Conclusions: This study demonstrated the ability of [HMMorph][Cl] as an inexpensive agent to pretreat both softwood and hardwood.


Assuntos
Betula/metabolismo , Etanol/metabolismo , Etanol/síntese química , Lignina/metabolismo , Celulose/metabolismo , Cloretos/química , Abies , Biocombustíveis , Fermentação , Hidrólise
19.
Rev. Col. Bras. Cir ; 46(5): e20192260, 2019. tab, graf
Artigo em Português | LILACS | ID: biblio-1057172

RESUMO

RESUMO Objetivo: avaliar o uso do curativo de filme e gel de biopolímero de celulose bacteriana no tratamento de pacientes com feridas isquêmicas submetidos à revascularização dos membros inferiores. Métodos: ensaio clínico randomizado realizado no ambulatório de Angiologia e Cirurgia Vascular do Hospital das Clínicas da Universidade Federal de Pernambuco, entre janeiro de 2017 e dezembro de 2018. Foram acompanhados 24 pacientes após revascularização de membros inferiores, divididos em dois grupos: Experimental, tratado com filme e gel de biopolímero de celulose bacteriana, e Controle, tratado com ácidos graxos essenciais. Os pacientes foram acompanhados em consultas semanais para troca dos curativos e o processo de cicatrização das feridas foi avaliado em um período de 90 dias. Resultados: a redução da área das feridas isquêmicas no período de 30 dias foi de 4,3cm2 (55%), em média, para o grupo experimental, e de 5,5cm2 (48,5%) para o grupo controle (p>0,05). A taxa de cicatrização completa, em 90 dias, foi de 34,8%, sendo 50% no grupo experimental e 18,2% no grupo controle (p=0,053). Conclusão: o filme de biopolímero de celulose bacteriana associada a gel pode ser utilizado como curativo no tratamento de feridas isquêmicas de pacientes submetidos à revascularização de membros inferiores


ABSTRACT Objective: to evaluate the use of a bacterial cellulose biopolymer film and gel dressing in the treatment of patients with ischemic wounds submitted to lower limb revascularization. Methods: we conducted a randomized clinical trial in the Angiology and Vascular Surgery outpatient clinic of the Clinics Hospital of the Federal University of Pernambuco, between January 2017 and December 2018. We followed 24 patients after lower limb revascularization, divided into two groups: Experimental, treated with bacterial cellulose biopolymer film and gel, and Control, treated with essential fatty acids. Patients attended weekly appointments to change dressings and had their wound healing processes evaluated over a period of 90 days. Results: the reduction of the ischemic wounds' areas after 30 days was 4.3cm2 (55%) on average for the experimental group, and the 5.5cm2 (48.5%) for the control group (p>0.05). The complete healing rate at 90 days was 34.8%, 50% in the experimental group and 18.2% in the control group (p=0.053). Conclusion: the bacterial cellulose biopolymer film associated with gel can be used as a dressing in the treatment of ischemic wounds of patients undergoing revascularization of the lower limbs.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Bandagens , Cicatrização/efeitos dos fármacos , Biopolímeros/uso terapêutico , Celulose/uso terapêutico , Extremidade Inferior/patologia , Isquemia/complicações , Isquemia/terapia , Fatores de Tempo , Resultado do Tratamento , Angioplastia , Extremidade Inferior/irrigação sanguínea , Géis/uso terapêutico , Isquemia/patologia , Pessoa de Meia-Idade
20.
Electron. j. biotechnol ; 36: 24-33, nov. 2018. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1048179

RESUMO

Background: α-L-Arabinofuranosidase (EC 3.2.1.55) catalyzes the hydrolysis of terminal α-L-1,2-, -1,3-, and -1,5- arabinofuranosyl residues in arabinose-containing polymers, and hence, it plays an important role in hemicellulose degradation. Herein, the bacterium Paenibacillus polymyxa, which secretes arabinofuranosidase with high activity, was selected for enzyme production, purification, and characterization. Results: Medium components and cultural conditions were optimized by the response surface method using shake flask cultures. Arabinofuranosidase production reached 25.2 U/mL under optimized conditions, which were pH 7.5, 28°C, and a basic medium supplemented with 1.5 g/L mannitol and 3.5 g/L soymeal. Furthermore, the arabinofuranosidase secreted by P. polymyxa, named as PpAFase-1, was partially purified from the supernatant using a DEAE Sepharose Fast Flow column and a hydroxyapatite column. The approximate molecular mass of the purified PpAFase-1 was determined as 56.8 kDa by SDS-PAGE. Protein identification by mass spectrometry analysis showed that the deduced amino acid sequence had significant similarity to the glycosyl hydrolase family 51. The deduced gene of 1515 bp was cloned and expressed in Escherichia coli BL21 (DE3) cells. Purified recombinant PpAFase-1 was active toward p-nitrophenyl-α-L-arabinofuranoside (pNPAraf). The Km and kcat values toward pNPAraf were 0.81 mM and 53.2 s−1 , respectively. When wheat arabinoxylan and oat spelt xylan were used as substrates, PpAFase-1 showed poor efficiency. However, a synergistic effect was observed when PpAFase-1 was combined with xylanase from Thermomyces lanuginosus. Conclusion: A novel GH51 enzyme PpAFase-1 was cloned from the genome of P. polymyxa and expressed in E. coli. This enzyme may be suitable for hemicellulose degradation on an industrial scale.


Assuntos
Paenibacillus polymyxa/enzimologia , Glicosídeo Hidrolases/metabolismo , Arabinose , Espectrometria de Massas , Celulose , Eletroforese em Gel de Poliacrilamida , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/biossíntese
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