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Purpose: To assess the cytotoxicity and wound healing properties of an alginate hydrogel containing calendula glycolic extract. Methods: Cell viability in murine fibroblasts (3T3 cells) was evaluated using MTT and SRB assays. The wound healing effect was tested in an incisional wound model on 50 female Wistar rats, divided into two groups: rats treated with alginate hydrogel (n = 25), and rats treated with calendula-alginate hydrogel. Wound healing was assessed by measuring wound retraction rate and histological analysis of lesion tissues over a 28-day period. Histological analyses were performed on days 2, 7, 14, 21, and 28 post-surgery to examine inflammatory infiltrate, macrophage count, and angiogenesis. Picrosirius red staining was used to compare the relative abundance of collagen types I and III fibers. Results: Cytotoxicity tests on 3T3 cells revealed increased cell viability with the calendula-alginate hydrogel. The calendula-alginate hydrogel also demonstrated a significant improvement in wound closure, supported by histopathological analysis, showing reduced inflammation, increased macrophage activity, and enhanced collagen deposition. Conclusions: These findings evidenced the therapeutic potential of combining calendula extract and alginate for promoting enhanced wound healing.

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Purpose: To describe the effects of melatonin associated with bacterial cellulose-based hydrogel on healing of skin wounds in diabetic rats. Methods: Streptozotocin was used to induce diabetes in Wistar rats. After wound induction, animals were randomly divided into groups GC, GDCC, GDCB, and GDMCB. Animals were evaluated in days 3, 7, and 14 for the following variables: glycemic levels, histopathological and histochemical analyses, healing rate, morphometry and C-reactive protein. Results: There was no change in glycemic levels in the diabetic animals as a result of the treatments; histopathological analyses showed better healing in GDCB and GDMCB groups, as well as histochemistry; at day 14, the highest healing rate was observed in animals from the GDMCB group, reaching almost 100%; morphometry revealed a significant increase of fibroblasts and reduction of macrophages and blood vessels in lesions treated with bacterial cellulose associated or not with melatonin when compared to the other experimental groups. There was also an increase in C-reactive protein in GDCC group at day 14. Conclusion: Bacterial cellulose-based dressings associated with systemic melatonin showed beneficial results in experimentally induced wounds in diabetic rats, favoring the healing process.

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Background: In this experimental protocol, we evaluated the immediate and delayed repair of the buccal branch of the facial nerve (BBFN) with heterologous fibrin biopolymer (HFB) as a coaptation medium and the use of photobiomodulation (PBM), performing functional and histomorphometric analysis of the BBFN and perioral muscles. Methods: Twenty-eight rats were divided into eight groups using the BBFN bilaterally (the left nerve was used for PBM), namely: G1 - control group, right BBFN (without injury); G2 - control group, left BBFN (without injury + PBM); G3 - Denervated right BBFN (neurotmesis); G4 - Denervated left BBFN (neurotmesis + PBM); G5 - Immediate repair of right BBFN (neurotmesis + HFB); G6 - Immediate repair of left BBFN (neurotmesis + HFB + PBM); G7 - Delayed repair of right BBFN (neurotmesis + HFB); G8 - Delayed repair of left BBFN (neurotmesis + HFB + PBM). Delayed repair occurred after two weeks of denervation. All animals were sacrificed after six weeks postoperatively. Results: In the parameters of the BBFN, we observed inferior results in the groups with delayed repair, in relation to the groups with immediate repair, with a significant difference (p < 0.05) in the diameter of the nerve fiber, the axon, and the thickness of the myelin sheath of the group with immediate repair with PBM compared to the other experimental groups. In measuring the muscle fiber area, groups G7 (826.4 ± 69.90) and G8 (836.7 ± 96.44) were similar to G5 (882.8 ± 70.51). In the functional analysis, the G7 (4.10 ± 0.07) and G8 (4.12 ± 0.08) groups presented normal parameters. Conclusion: We demonstrated that delayed repair of BBFN is possible with HFB, but with worse results compared to immediate repair, and that PBM has a positive influence on nerve regeneration results in immediate repair.(AU)

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ABSTRACT Purpose The aim of this work was to analyze the effect of fibrin biopolymer sealant (FS) associated or not to aquatic exercise (AE) on the calcaneal tendon repair. Methods Forty-four female Wistar rats were randomly divided into four experimental groups: Lesion control (L), Lesion and FS (LS), Lesion and AE (LE) and Lesion and FS associated to AE (LSE). The edema volume (EV), collagen ratio, and histopathological analysis were evaluated after 7, 14, and 21 days of partial tendon transection. Results The EV was statistically reduced for all treatment groups after 7 and 21 days when compared to L group. The LS and LSE had the highest EV reduction after 21 days of treatment. The FS group didn't induce tissue necrosis or infections on the histopathological analysis. It was observed tenocytes proliferation, granulation tissue and collagen formation in the tendon partial transection area in the FS group. The LSE demonstrated higher amount of granulation tissue and increased the collagen deposition at the injury site. Conclusions Our data suggests that the therapeutic potential of the association of heterologous fibrin biopolymer sealant with aquatic exercise program should be further explored as it may stimulate the regeneration phase and optimize calcaneal tendon recovery.

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La termografía es eficaz para detectar la temperatura de la superficie corporal y puede utilizarse como método auxiliar para diagnosticar procesos inflamatorios y para evaluar patrones de cicatrización, lo que permite su amplio uso en Medicina Veterinaria. El procedimiento ha ganado protagonismo por ser una técnica no invasiva, indolora, de bajo costo y segura, ya que elimina la necesidad del uso de contrastes, sedación y radiación. El objetivo de este artículo es analizar la eficacia del uso de la termografía en la evaluación de la biocompatibilidad en la reparación del tejido traqueal, así como identificar procesos inflamatorios tras la implantación de la prótesis impresa en nailon con impresión 3D asociada al elastómero termoplástico - PCTPE. Se dividieron quince conejos blancos de Nueva Zelanda (Oryctolagus cuniculus) machos en tres grupos de diferentes períodos de evaluación (siete, 15 y 30 días). Se implantaron prótesis tridimensionales tras la resección completa de tres anillos traqueales. La evaluación de las imágenes termográficas se realizó en el lugar de implantación de la prótesis traqueal justo antes del procedimiento quirúrgico e inmediatamente antes de la eutanasia. Hubo una diferencia significativa entre los grupos, ya los 30 días la temperatura mínima (p = 0,0357), media (p = 0,0135) y máxima (p = 0,0058) fue menor en comparación con los otros grupos...

Thermography is efficient for detecting body surface temperature and can be used as an auxiliary method for the diagnosis of inflammatory processes and in the evaluation of scarring patterns, which allows its wide use in Veterinary Medicine. The procedure has gained prominence, as it is a non-invasive, painless, low-cost and safe technique, since it does not require the use of contrasts, sedation and radiation. The objective of this article is to analyze the efficiency of the use of thermography in the evaluation of biocompatibility in tracheal tissue repair, as well as to identify inflammatory processes after implantation of the 3D printed impression prosthesis of nylon associated with the thermoplastic elastomer - PCTPE. Fifteen male New Zealand White rabbits (Oryctolagus cuniculus) were divided into three groups of different evaluation periods (seven, 15 and 30 days). Three-dimensional prostheses were implanted after complete resection of three tracheal rings. The evaluation of the thermographic images was performed at the place of implantation of the tracheal prosthesis just before the surgical procedure and immediately before euthanasia. There was a significant difference between the groups, and at 30 days the minimum (p = 0,0357), average (p = 0,0135) and maximum (p = 0,0058) temperature was lower when compared with the other groups...

A termografia é eficiente para detecção da temperatura da superfície corporal e pode ser utilizada como método auxiliar de diagnóstico de processos inflamatórios e na avaliação de padrões cicatriciais, o que permite sua ampla utilização na Medicina Veterinária. O procedimento tem ganhado destaque, pois trata-se de técnica não invasiva, indolor, de baixo custo e segura, pois dispensa a necessidade do uso de contrastes, sedação e radiação.  O objetivo desse artigo é analisar a eficiência do uso da termografia na avaliação da biocompatibilidade em reparação tecidual traqueal, bem como identificar processos inflamatórios após a implantação da prótese impressa em impressão 3D de náilon associado ao elastômero termoplástico- PCTPE. Quinze coelhos machos, da linhagem Nova Zelândia Branco (Oryctolagus cuniculus), foram distribuídos em três grupos de períodos de avaliação diferentes (sete, 15 e 30 dias). As próteses tridimensionais foram implantadas após ressecção completa de três anéis traqueais. A avaliação das imagens termográficas foi efetuada no local de implantação da prótese traqueal no momento anterior ao procedimento cirúrgico e imediatamente antes da eutanásia. Houve diferença significativa entre os grupos, sendo que aos 30 dias a temperatura mínima (p=0,0357), média (p=0,0135) e máxima (p=0,0058) foi menor quando comparado com os demais grupos...

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Venous ulcers are the main causes of chronic lower-limb ulcers. The healing difficulties encourage the research and development of new products in order to achieve better therapeutic results. Fibrin sealant is one of these alternatives. Besides being a validated scaffold and drug delivery system, it possesses excellent healing properties. This review covered the last 25 years of the literature and showed that the fibrin sealant is used in various clinical situations to promote the healing of different types of ulcers, especially chronic ones. These are mostly venous in origin and usually does not respond to conventional treatment. Commercially, only the homologous fibrin sealants obtained from human blood are available, which are highly efficient but very expensive. The heterologous fibrin sealant is a non-commercial experimental low-cost product and easily produced due to the abundance of raw material. The phase I/II clinical trial is already completed and showed that the product is safe and promisingly efficacious for the treatment of chronic venous ulcers. In addition, clinical proteomic strategies to assess disease prognosis have been increasingly used. By analyzing liquid samples from the wounds through proteomic strategies, it is possible to predict before treatment which ulcers will evolve favorably and which ones will be difficult to heal. This prognosis is only possible by evaluating the expression of isolated proteins in exudates and analysis using label-free strategies for shotgun. Multicentric clinical trials will be required to evaluate the efficacy of fibrin sealant to treat chronic ulcers, as well as to validate the proteomic strategies to assess prognosis.(AU)

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This study set out to determine the physical and mechanical properties of edible films made from native starch extracted from non-exportable Ecuadorian bananas (Musa sapientum L.). The following treatments were applied: 0.5% starch - 0.25% glucose (T1), 0.5% starch - 0.5% glucose (T2), 1% starch - 0.25% glucose (T3), and 1% starch - 0.5% glucose (T4). Variables such as physicochemical properties, amylose content, maximum gelation temperature, and the morphology of native starch granules were assessed. Variables in the film, such as thickness, opacity, film solubility, and tensile strength, were also measured. The fruit used in this study was composed of 88.55% starch (dry basis, 15.35% amylose). The starch granules had a dominant ovoid morphology with an average diameter of 25 - 30 m. The peak gelatinization temperature was 73.80 °C. The maximum value for viscosity was 3,836 cP at 86.8 °C. Films that presented good malleability, thickness, transparency, tensile strength, and low solubility were obtained from T4, which turned out to be the best treatment.

O objetivo do presente trabalho foi determinar propriedades físicas e mecânicas em filmes comestíveis obtidos a partir de amido nativo de banana equatoriana não exportada (Musa sapientum L.). Os tratamentos utilizados foram: 0,5% de amido - 0,25% de glicose (T1), 0,5% de amido - 0,5% de glicose (T2), 1% de amido - 0,25% de glicose (T3) e 1% de amido - 0,5% de glicose (T4). Foram determinadas variáveis como características físico-químicas, teor de amilose, temperatura de gelatinização máxima, morfologia dos grânulos de amido nativo. Foram obtidas variáveis em filmes como espessura, opacidade, solubilidade do filme. E a resistência à tração (por texturometria) foi medida. Os frutos utilizados nesta pesquisa apresentaram 88,55% de amido (base seca; amilose representou 15,35% do mencionado). A morfologia dominante encontrada nos grânulos de amido era ovóide e 25 - 30 m de diâmetro médio. A temperatura máxima de gelatinização foi de 73,80 °C. O valor máximo de viscosidade ocorrido foi de 3.836 cP a 86,8 °C. Filmes com boa maleabilidade, espessura, transparência, resistência à tração e baixa solubilidade foram obtidos de T4, tornando-se o melhor tratamento.

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Abstract Purpose: To evaluate the efficacy of the cellulosic exopolysaccharide membrane (CEM) as a urethral reinforcement for urethrovesical anastomosis. Methods: Twenty eight rabbits were submitted to urethrovesical anastomosis with or without CEM reinforcement. The animals were divided into 4 groups: C7, CEM7, C14 and CEM14: (C= only anastomosis or CEM = anastomosis + CEM), evaluated after 7 weeks, and 14 weeks. The biointegration and biocompatibility of CEM were evaluated according to stenosis, fistula, urethral wall thickness, urethral epithelium, rate of inflammation and vascularization. Results: Between the two experimental groups, the difference in the number of stenosis or urinary fistula was not statistically significant. The morphometric analysis revealed preservation of urethral lumen, well adhered CEM without extrusion, a controlled inflammatory process and implant vascularization. The urothelium height remained constant over time after CEM reinforcement and the membrane wall was thicker, statistically, after 14 weeks. Conclusion: The absence of extrusion, stenosis or urinary fistula after 14 weeks of urethrovesical anastomosis demonstrates cellulosic exopolysaccharide membrane biocompatibility and biointegration with tendency to a thicker wall.

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PURPOSE: To evaluate the effects of particulate (granule-shaped) SCB on bone repair relating it to its biocompatibility and bone neoformation. METHODS: Thirty Wistar rats were submitted to a one 7-mm-diameter defect and divided equally into three experimental groups, with two different postoperative times of evaluation, 90 and 120 days. Each calvaria defect was filled up with clot (control group), particulated autogenous bone or granulated SCB. Five animals of each group were assessed at 90 and 120 days after surgery. In these two periods, histological and histometric analysis were obtained. RESULTS: The clot group showed a bone resorption trend while the autogenous bone group a bone repair trend. However in the SCB group, the critical defect filled up only with fibrous connective tissue and presented none bone neoformation. CONCLUSION : The sugarcane biopolymer when used in critical size defects was a biocompatible material and proved to be a good material to fill bone cavities, keeping them as uniform areas filled with soft tissue and avoiding the tissue shrinkage.

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Este trabalho teve como objetivo avaliar o efeito de filmes formados por pectina, albúmen de ovo, carragena, gelatina, fécula de batata, xantana e amido de milho na conservação de banana cv. Caturra. As bananas foram sanitizadas e imersas em soluções filmogênicas de pectina (2%), albúmen de ovo (100%), carragena (2%), gelatina (5%), fécula de batata (2%) com glicerol (0,7%), xantana (1%), amido de milho (2%) com glicerol (0,7%) e o controle (0%), sendo armazenadas a 18ºC a 80% de UR por 8 dias. As bananas revestidas foram avaliados de acordo com a perda de massa, taxa de perda de massa, sólidos solúveis totais, cor (luminosidade e croma b*) e firmeza, nos tempos de zero hora, 2, 6, 7 e 8 dias. Ao final do período de armazenamento as bananas cv Caturra revestidas com filmes de pectina promoveram menor perda de massa e se mantiveram dentro do limite permitido (7%) até os 4,9 dias. O revestimento com carragena mostrou menor aumento dos sólidos solúveis totais, já os filmes de albúmen proporcionaram menores reduções da firmeza e variações da coloração amarela e o revestimento com fécula de batata melhorou a luminosidade nos frutos. Este aspecto mostra uma contribuição dos filmes na manutenção da qualidade da banana cv. Caturra. No entanto, outros parâmetros de qualidade devem ser avaliados, buscando conhecer outros efeitos desses filmes sobre a banana.

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Este trabalho se propôs revisar a temática das embalagens para alimentos, presentes e fundamentais na indústria de alimentos. As embalagens têm como principais funções conter, proteger e conservar o produto. Além disso, trata-se de um importante componente da economia nos países industrializados. Nas últimas décadas, o desenvolvimento de novas tecnologias de materiais aplicadas às embalagens de alimentos vem resgatando a importância da embalagem como ferramenta de sustentabilidade para a sociedade, onde os benefícios são altamente significativos para o meio ambiente e para a segurança dos alimentos.

This work aims to review the food packaging theme, predominate and fundamental in food industry, the packaging have main functions contain, protect and preserve the product. In addition, the packaging sector is an important sector of the economy in industrialized countries. In the last decades, the development of new materials technologies applied to food packaging has been recovering the importance of packaging as a tool for sustainability in the society, bringing significant benefits for the environment and for food safety.

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O presente trabalho objetivou produzir nanofibras para a finalidade de uso em regeneração tecidual, utilizando álcool polivinílico (PVA) e colágeno, extraído da pele de rã touro (Lithobates catesbeianus), a partir da técnica de eletrofiação. O colágeno extraído da pele de rã touro foi purificado, e uma porção desse colágeno foi hidrolisado utilizando a enzima Alcalase®, nas seguintes condições: temperatura de 55º C, tempo de 3 horas, concentração enzima:substrato de 1% e pH 6,92. Foram produzidos 4 nanofibras de PVA/Colágeno com diferentes concentrações de colágeno hidrolisado (CH) (0%, 10%, 20% e 30% respectivamente) (m/m) de PVA. O processo de extração e purificação do colágeno foi eficiente e favorável para a produção das nanofibras, apresentando 0,07 ± 0,78 % de matéria mineral e 0,06 ± 0,01 % de material lipídico. O rendimento em base seca observado na extração do colágeno bruto foi de 16,58%. O hidrolisado produzido a partir do colágeno purificado apresentou grau de hidrólise e proteína solúvel de 5,70% e de 53,97 mg mL-1 , respectivamente. A atividade antioxidante do colágeno hidrolisado foi de IC50 6,82 ± 0,09 mg mL-1 , as nanofibras PVA/Colágeno+CH não apresentaram atividade antioxidante. O colágeno hidrolisado e as nanofibras demonstraram atividade antimicrobiana contra a cepa de Staphylococcus aureus. Os curativos produzidos de PVA/COL+CH 0%, 10%, 20% e 30%, demonstraram características físicoquímicas que estão de acordo com a literatura em relação as análises termogravimétricas e Espectroscopia (FTIR). Em relação a microscopia eletrônica de varredura, o filme PVA/COL+CH 10% destacou-se, pois apresentou maior uniformidades nas nanofibras, esse resultado corrobora com os resultados da avaliação mecânica, onde obteve maior porcentagem de elongação. Por fim, os filmes produzidos nessa pesquisa apresentam grande potencial para a sua utilização como curativos epiteliais, sendo um produto de alto valor agregado que poderá ser empregado para auxiliar a regeneração epitelial.

The present research aimed to produce nanofibers for use in tissue regeneration, using polyvinyl alcohol (PVA) and collagen, extracted from the skin of bullfrogs (Lithobates catesbeianus), using the electrospinning technique. The collagen extracted from the bullfrog skin was purified, and a portion of this collagen was hydrolyzed using the Alcalase® enzyme, under the following conditions: temperature of 55º C, time of 3 hours, enzyme:substrate concentration of 1% and pH 6.92. Four PVA/Collagen nanofibers were produced with different concentrations of hydrolyzed collagen (CH) (0%, 10%, 20% and 30% respectively) (m/m) of PVA. The collagen extraction and purification process were efficient and favorable to produce nanofibers, presenting 0.07 ± 0.78 % of ash and 0.06 ± 0.01 % of lipid material. The dry basis yield observed in the extraction of crude collagen was 16.58%. The hydrolysate produced from purified collagen showed a degree of hydrolysis and soluble protein of 5.70% and 53.97 mg mL-1 , respectively. The antioxidant activity of the hydrolyzed collagen was IC50 6.82 ± 0.09 mg mL-1 , the PVA/Collagen+CH nanofibers showed no antioxidant activity. Hydrolyzed collagen and nanofibers demonstrated antimicrobial activity against the Staphylococcus aureus strain. The nanofibers produced from PVA/COL+CH 0%, 10%, 20% and 30% showed physicochemical characteristics that agree with the literature regarding thermogravimetric analysis and Spectroscopy (FTIR). In relation to scanning electron microscopy, the PVA/COL+CH 10% nanofiber stood out, as it presented greater uniformity in the nanofibers, this result corroborates the results of the mechanical evaluation, where it obtained a higher percentage of elongation. Finally, the films produced in this research have great potential for use as epithelial dressings, being a product of high added value that can be used to assist epithelial regeneration.

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Alternativas que visem o aproveitamento de resíduos tem sido cada vez mais procuradas, com vistas a mitigar os impactos ambientais indesejáveis. Nesse contexto sabe-se que a produção de pescado é uma atividade que gera grande quantidade de resíduos e assim, se faz necessário o reaproveitamento dessa matéria-prima que é fonte de diversos biopolímeros com múltiplas aplicações e propriedades funcionais. Nesse contexto, a nanotecnologia vem despontando como uma forma de explorar os potenciais dos biomateriais em virtude de sua versatilidade e ampla gama de utilizações, incluindo a produção de nanofibras. Recentemente, a reticulação também vem sendo bastante empregada a fim de aprimorar as características desses materiais. Diante do exposto, o objetivo deste estudo foi elaborar nanofibras de gelatina de tilápia (Oreochromis niloticus) com incorporação de ácido ferúlico através da técnica de fiação de sopro e caracterizá-las em termos de FTIR, DSC, solubilidade, viscosidade, grau de reticulação, liberação in vitro, atividade antioxidante e microscopia eletrônica de varredura (MEV). As nanofibras contendo ácido ferúlico apresentaram excelente atividade antioxidante, variando entre 71,47 e 90,49%. Os espectros vibracionais (FTIR) mostraram um deslocamento do pico referente à Amida III, de 1247 cm-1 nas nanofibras controle, para 1258, 1264 e 1267 cm-1 para as nanofibras com 5, 7,5 e 10% de ácido ferúlico respectivamente, indicando uma possível interação entre o A.F. e as moléculas da gelatina, o que foi confirmado pela análise do grau de reticulação. Os diâmetros encontrados foram de 882,18, 1060,66, 984,23 e 1660,99 nm para as nanofibras controle e com 5, 7,5 e 10% de A.F. respectivamente e observou-se que a morfologia foi influenciada pela adição do reticulante, com formação de gotas e agregados nanofibrosos e aumentos no diâmetro. Os termogramas de DSC mostraram deslocamento dos picos referentes a Tg e Tm em relação ao controle e apresentaram bom indicativo de melhorias na resistência térmica após adição do ácido ferúlico. As nanofibras também apresentaram bom perfil de liberação do A.F., e sua adição também tornou a viscosidade das soluções de fiação mais adequada ao sistema utilizado. Em virtude das suas boas propriedades, as nanofibras obtidas neste estudo são candidatas adequadas à elaboração de bioembalagens na área de alimentos.

Alternatives aimed at the use of waste have been increasingly sought, with a view to mitigating undesirable environmental impacts. In this context, it is known that fish production is an activity that generates a large amount of waste and thus, it is necessary to reuse this raw material that is a source of several biopolymers with multiple applications and functional properties. In this context, nanotechnology has emerged as a way of exploring the potential of biomaterials due to their versatility and wide range of uses, including the production of nanofibers. Recently, crosslinking has also been widely used in order to improve the characteristics of these materials. In view of the above, the objective of this study was to elaborate tilapia (Oreochromis niloticus) gelatin nanofibers with incorporation of ferulic acid through the blow spinning technique and characterize them in terms of FTIR, DSC, solubility, viscosity, degree of crosslinking, in vitro release, antioxidant activity and scanning electron microscopy (SEM). Nanofibers containing ferulic acid showed excellent antioxidant activity, ranging from 71.47 to 90.49%. The vibrational spectra (FTIR) showed a shift of the amide III peak, from 1247 cm-1 in the control nanofibers, to 1258, 1264 and 1267 cm-1 for the nanofibers with 5, 7.5 and 10% ferulic acid, respectively. , indicating a possible interaction between the AF and gelatin molecules, which was confirmed by analyzing the degree of cross-linking. The diameters found were 882.18, 1060.66, 984.23 and 1660.99 nm for the control nanofibers and with 5, 7.5 and 10% A.F. respectively and it was observed that the morphology was influenced by the addition of the crosslinker, with the formation of droplets and nanofibrous aggregates and increases in diameter. The DSC thermograms showed displacement of the peaks referring to Tg and Tm in relation to the control and showed a good indication of improvements in the thermal resistance after addition of ferulic acid. The nanofibers also showed a good A.F. release profile, and their addition also made the viscosity of the spinning solutions more suitable for the system used. Due to their good properties, the nanofibers obtained in this study are suitable candidates for the elaboration of biopackaging in the food area.

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PURPOSE: To assess the histological response of damaged osteochondral tissue in the femoral condyles of rabbits after repairing the wounds with sugar cane biopolymer gel - compared to the control group. METHODS: The study investigated 16 New Zealand rabbits, at 90, 120 and 180 days after surgery. In all the animals, a lesion of 3.2 mm in diameter and 4 mm deep was induced in each right and left femoral condyle. Each animal has provided both knees, divided into medial and lateral condyle, resulting in 64 samples. 32 knees were divided into two groups: Right knee, medial and lateral condyles, filled with biopolymer; Left knee, medial and lateral condyles, unfilled. The anatomical specimens were removed, and subjected to histological techniques and morphometric and statistical analysis. RESULTS: In all the periods of the group under study an inflammatory reaction mediated by giant cells and mononuclear cells was found, while in the control group there was early healing produced by fibroblasts and few mononuclear cells with statistical significance between groups. CONCLUSION: The biopolymer gel caused an inflammatory reaction mediated by giant cells and mononuclear cells while the control group there was cicatrization mediated by fibroblasts.

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PURPOSE: To compare the inflammatory reaction caused by the injection of a sugarcane biopolymer (SCB) into the vocal fold of rabbits with that caused by calcium hydroxyapatite (CaH). METHODS: CaH (Radiesse(r)) and SCB gel were injected respectively into the right and left vocal cords of thirty rabbits. The rabbits were distributed into two equal groups and sacrificed at three and twelve weeks after injection. We then evaluated the intensity of the inflammatory reaction, plus levels of neovascularization, fibrogenesis and inflammatory changes in the vocal mucosa. RESULTS: The vocal cords injected with CaH had a stronger inflammatory reaction by giant cells in both study periods. The SCB group had a more intense inflammatory involvement of polymorphonuclear cells three weeks after injection. SCB caused a higher level of neovascularization compared with CaH three weeks after the procedure. CONCLUSION: Whereas calcium hydroxyapatite triggers a more intense and lasting inflammatory reaction mediated by giant cells, sugarcane biopolymer causes a greater response from polymorphonuclear leukocytes, as well as higher levels of vneoascularization three weeks after injection. .

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PURPOSE: To evaluate the biocompatibility and local sensibility reaction to bacterial cellulose hydrogel (0.8%) implanted in subcutaneous tissue of rabbits. METHODS: Fifteen New Zeland rabbits were randomly allocated into three groups: T1, 7 days, T2, 21 days, and T3, 84 days. The new material was implanted in the subcutaneous tissue of the ear; on the scalp over the periosteum; and on the outer and inner surfaces of the thighs, in the aponeurosis of the muscle. At 7, 21 and 84 postoperative days, the material was collected for histological study. The clinical signs, inflammatory response, angiogenesis and fibrogenesis were variables used for analysis of the biocompatibility and biological reactivity to BCH. Analyses were performed with an AXIO(r) Imager. The statistical tests were performed using the GraphPad Prism 5.0 program(r) RESULTS: The intensity of the inflammatory infiltrate, considering the different cell types (PMN, LMN and GC), was statistically significant, with group T1 different from groups T2 and T3 (p = 0.0124 and p <0.0001, respectively) and T2 different from the T3 group (p = 0.0007). Fibrogenesis grade 1 was the most prevalent in groups T1 (55.4%) and T2 (44.6%). The formation of neovascularization in the group was identified in 84.4% of samples. CONCLUSION: Bacterial cellulose hydrogel (0.8%) is biocompatible, integrating with the subcutaneous tissue of rabbits and inducing tissue remodeling. .

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Growth associated biosynthesis of medium chain length poly-3-hydroxyalkanoates (mcl-PHA) in Pseudomonas putida Bet001 isolated from palm oil mill effluent was studied. Models with substrate inhibition terms described well the kinetics of its growth. Selected fatty acids (C8:0 to C18:1) and ammonium were used as carbon and nitrogen sources during growth and PHA biosynthesis, resulting in PHA accumulation of about 50 to 69% (w/w) and PHA yields ranging from 10.12 g L-1 to 15.45 g L-1, respectively. The monomer composition of the PHA ranges from C4 to C14, and was strongly influenced by the type of carbon substrate fed. Interestingly, an odd carbon chain length (C7) monomer was also detected when C18:1 was fed. Polymer showed melting temperature (Tm) of 42.0 (± 0.2) °C, glass transition temperature (Tg) of -1.0 (± 0.2) °C and endothermic melting enthalpy of fusion (ΔHf) of 110.3 (± 0.1) J g-1. The molecular weight (Mw) range of the polymer was relatively narrow between 55 to 77 kDa.

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Polyhydroxyalkanoates (PHAs) can be produced by microorganisms and are a biodegradable alternative to fossil-fuel based plastics. Currently, the focus is on reducing production costs by exploring alternative substrates for PHAs production, and on producing copolymers which are less brittle than monomers. Accordingly, this study used a substrate consisting of wastewater from waste-glycerol fermentation, supplemented with different amounts of acetic and propionic acids. These substrates were used to feed mixed microbial communities enriched from activated sludge in a sequencing batch reactor. A reactor supplemented with 2 mL of acetic acid produced 227.8 mg/L of a homopolymer of hydroxybutyrate (3HB); 4 mL of acetic acid produced 279.8 mg/L 3HB; whereas 4 mL of propionic acid produced 673.0 mg/L of a copolymer of 3HB and 3HV (hydroxyvalerate). Ribosomal Intergenic Spacer Analysis (RISA) was used to show the differences between the communities created in the reactors. Thauera species predominated in biomass that produced 3HB; Paracoccus denitrificans in the biomass that produced 3HB-co-3HV. Because P. denitrificans produced the more desirable copolymer, it may be advantageous to promote its growth in PHAs-producing reactors by adding propionate.

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PURPOSE: To evaluate the tissue response of the mucosa of the tympanic cavity of guinea pigs, when receiving biodegradable implant. METHODS: A total of 20 male guinea pigs were divided into 2 groups. After paracentesis in both ears, a biodegradable polymer of poly lactic-co-glycolic acid was implanted in only one middle ear. Histological analysis using neutrophil exudate and vascular neoformation (acute inflammation) and fibroblast proliferation and mononuclear inflammatory cells (chronic inflammation) as parameters was performed after 10 and 30 days of survival (groups 1 and 2, respectively). RESULTS: Four ears in group 1 and 7 in group 2 had an increase of neutrophil exudate. Vascular neoformation occurred in ears with or without the implant, in both groups. Fibroblast proliferation and mononuclear inflammatory cells (lymphocytes and macrophages) increased in ears with implant in group 2. CONCLUSION: The tissue response by histological analysis of the mucosa of the tympanic cavity of guinea pigs, when receiving biodegradable implant, showed no statistically significant difference between ears with or without the implant. .

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Colivet, J. Desenvolvimento e caracterização de filmes biodegradáveis à base de amido modificado de mandioca e óleo de melancia (Citrullus lanatus). 145f. Tese (Doutorado). Faculdade de Zootecnia e Engenharia de Alimentos. Universidade de São Paulo. 2017. A produção de filmes biodegradáveis à base de amido representa um desafio tecnológico, pois estas matrizes são altamente sensíveis à água. Neste sentido, as pesquisas estão sendo realizadas a fim de melhorar as caraterísticas de hidrofobicidade sem afetar a integridade estrutural das matrizes. Dentre os compostos comumente empregados para melhorar as características de filmes biodegradáveis, pode-se mencionar os óleos e ácidos graxos. O óleo de sementes de melancia apresenta alto potencial de aplicação em matrizes filmogênicas, pois além da possibilidade de melhorar as propriedades de barreira, apresenta compostos fitoquímicos com atividade antioxidante, que podem conferir um caráter ativo aos materiais produzidos. Neste contexto, o objetivo deste trabalho foi desenvolver e caracterizar filmes à base de amido modificado de mandioca e óleo de sementes de melancia. O óleo de sementes de melancia foi extraído por batelada com etanol pressurizado, sob diferentes temperaturas de extração (40, 60 e 80°C) e diferentes comprimentos de leito de extração (L1 = 4,2 cm, L2 = 9,8 cm e L3 = 15,8 cm). A cinética de extração foi matematicamente descrita utilizando-se o modelo de Peleg e os óleos caraterizados quanto à atividade antioxidante. Posteriormente foram testados quatro amidos modificados de mandioca (amido reticulado, AR; amido acetilado, AA; amido não modificado, ANM e amido duplamente modificado, AAR) com a finalidade de selecionar o que apresentasse melhores caraterísticas na produção de filmes quanto ao caráter hidrofóbico. Os filmes foram produzidos pela técnica de casting, utilizando - se concentrações fixas de amido e sorbitol (4 e 1,2 g/100g de solução filmogênica, respectivamente). O caráter hidrofóbico das matrizes foi avaliado pela determinação da solubilidade, grau de inchamento, permeabilidade ao vapor de água e ângulo de contato. Adicionalmente, foram produzidas emulsões através da técnica de Pickering, com diferentes concentrações de óleo e amido e caraterizadas quanto à estabilidade, tamanho de partículas e polidispersidade. A emulsão com maior estabilidade foi incorporada na formulação de filmes à base de AR em concentrações de 0 a 0,5 g de óleo na emulsão/100 g de solução filmogênica. Todos os filmes foram caracterizados quanto às propriedades mecânicas, microscopia, espectroscopia de infravermelho (FTIR), difração de raios X, cor, solubilidade, inchamento, permeabilidade ao vapor de água e ângulo de contato. Os resultados da extração de óleos mostraram rendimentos superiores sob temperaturas de 80°C e melhor atividade antioxidante a 60°C. O modelo de Peleg apresentou um bom ajuste, observando-se coeficientes de correlação altos (R2 > 0,90). A caraterização dos filmes produzidos com diferentes amidos modificados mostrou que o AR formou matrizes com maior ângulo de contato, menor grau de inchamento e maior resistência mecânica. As emulsões com maior de estabilidade foram produzidas com altas concentrações de óleo e amido (15 e 12 g/100 g de emulsão, respectivamente). Os filmes produzidos com incorporação de óleo na forma de emulsão Pickering apresentaram caráter mais hidrofóbico, sendo também alteradas as caraterísticas estruturais com o aumento da concentração de óleo. Os filmes produzidos com a incorporação de óleo em forma de emulsão apresentaram conteúdos de fenólicos totais de 0,19 a 5,68 mg equivalente de ácido gálico/100g de filmes. No entanto, os filmes não apresentaram atividade antioxidante frente ao radical DPPH.

Colivet, J. Development and characterization of biodegradable films based on modified cassava starch and watermelon oil (Citrullus lanatus). 2017. 145p. Thesis (PhD). Faculdade de Zootecnia e Engenharia de Alimentos. Universidade de São Paulo. 2017. The production of biodegradable films based on starch represents a technological challenge because these matrices are highly sensitive to water. In this sense, the research is being carried out in order to improve the characteristics of hydrophobicity without affecting the structural integrity of the matrices. Among the compounds commonly used to improve the characteristics of biodegradable films, the oils and fatty acids can be highlighted. The oil of the watermelon seeds presents high potential of application in filmogenic matrices because in addition to the possibility of improving the barrier properties, it presents phytochemical compounds with antioxidant activity, which can impart an active characteristic to the produced materials. In this context, the objective of this work was to develop and characterize films based on modified cassava starch and watermelon oil. The watermelon oil was extracted in batches with pressurized ethanol under different extraction temperatures (40, 60, and 80°C) and different extraction bed lengths (L1 = 4.2 cm, L2 = 9.8 cm, and L3 = 15.8 cm). The kinetics of extraction were mathematically described using the Peleg model and the oils characterized for antioxidant activity. Four modified starches of cassava (reticulated starch, AR, acetylated starch, AA, unmodified starch, ANM, and doubly modified starch, AAR) were then tested in order to select the material with the best hydrophobic characteristics. The films were produced by the casting technique, using fixed concentrations of starch and sorbitol (4 and 1.2 g/100 g of film-forming solution, respectively). The hydrophobic characteristic of the matrices was evaluated by determining the solubility, degree of swelling, permeability to water vapor, and contact angle. In addition, emulsions were produced using the Pickering technique with different concentrations of oil and starch and then, characterized for stability, particle size, and polydispersity. The results of the extraction showed higher yields under temperatures of 80°C and better antioxidant activity at 60°C. The Peleg model presented a good fit, observing high correlation coefficients (R2> 0.90). The characterization of the films produced with different modified starches showed that AR formed matrices with higher contact angle, lower degree of swelling, and higher mechanical resistance. Emulsions with the highest degree of stability were produced with high concentrations of oil and starch (15 and 12 g/100 g of emulsion, respectively). The films produced with oil incorporation in the form of Pickering emulsion presented a more hydrophobic characteristic, and the structural characteristics were also altered with the increase of oil concentration. The films produced with the incorporation of oil in emulsion form presented total phenolic contents of 0.19 to 5.68 mg of gallic acid equivalent/100 g of films. However, the films did not present antioxidant activity against the DPPH radical.