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Braz. j. biol ; 84: e254010, 2024. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1345561


Abstract The impact of fish oil concentration on the oxidative stability of microcapsules through the spray drying process using chitosan and maltodextrin as wall material was studied. Emulsions were prepared with different Tuna fish oil (TFO) content (TFO-10%, TFO20%, TF030% TF0-40%) while wall material concentration was kept constant. Microencapsulated powder resulting from emulsion prepared with high fish oil load have high moisture content, wettability, total oil and low encapsulation efficiency, hygroscopicity and bulk tapped density. Oxidative stability was evaluated periodically by placing microcapsules at room temperature. Microcapsules prepared with TFO-10% presented high oxidative stability in terms of peroxide value (2.94±0.04) and anisidine value (1.54±0.02) after 30 days of storage. It was concluded that optimal amounts of fish oil for microencapsulation are 10% and 20% using chitosan and maltodextrin that extended its shelf life during study period.

Resumo Foi estudado o impacto da concentração de óleo de peixe na estabilidade oxidativa de microcápsulas por meio do processo de secagem por atomização, utilizando quitosana e maltodextrina como material de parede. As emulsões foram preparadas com diferentes teores de óleo de atum (TFO) (TFO-10%, TFO20%, TF030% TF0-40%), enquanto a concentração de material de parede foi mantida constante. O pó microencapsulado resultante da emulsão preparada com alta carga de óleo de peixe tem alto teor de umidade, molhabilidade e óleo total e baixa eficiência de encapsulação, higroscopicidade e densidade extraída a granel. A estabilidade oxidativa foi avaliada periodicamente colocando microcápsulas à temperatura ambiente. As microcápsulas preparadas com TFO-10% apresentaram alta estabilidade oxidativa em termos de valor de peróxido (2,94 ± 0,04) e valor de anisidina (1,54 ± 0,02) após 30 dias de armazenamento. Concluiu-se que as quantidades ideais de óleo de peixe para microencapsulação são de 10% e 20% usando quitosana e maltodextrina que prolongaram sua vida útil durante o período de estudo.

Animals , Fish Oils , Chitosan , Powders , Tuna , Oxidative Stress
Chinese Journal of Biotechnology ; (12): 615-624, 2021.
Article in Chinese | WPRIM | ID: wpr-878586


To effectively solve the serious impact of high oil in the kitchen wastewater on the downstream treatment process, an excellent oil-degrading strain Aeromonas allosaccarophila CY-01 was immobilized to prepare Chitosan-Aeromonas pellets (CH-CY01) by using chitosan as a carrier. Oil degradation condition and efficiency of CH-CY01 pellets were assessed. The growth of immobilized CH-CY01 was almost unaffected, and the maximum degradation rate of soybean oil was 89.7%. Especially at 0.5% NaCl concentration, oil degradation efficiency of CH-CY01 was increased by 20% compared with free cells. In the presence of a surfactant (sodium dodecylbenzene sulfonate) at 1 mg/L, the degradation efficiency of oil by CH-CY01 was increased by 40%. Moreover, using the high-oil catering wastewater as the substrate, more than 80% of the solid oil was degraded with 1% (V/V) CH-CY01 pellets treatment for 7 days, significantly higher than that of free cells. In summary, immobilized CH-CY01 significantly improved the efficiency of oil degradation.

Aeromonas , Chitosan , Surface-Active Agents , Waste Water
Chinese Journal of Biotechnology ; (12): 2322-2333, 2021.
Article in Chinese | WPRIM | ID: wpr-887799


Chitosan is a natural polysaccharide that is widely used in food, textile, cosmetics, and medical industries. In the field of stomatology, chitosan and its derivatives are widely used in the treatment of many common oral diseases due to a variety of excellent biological properties, such as anti-infection, drug-loading, remineralization and osteogenesis. This review summarized the latest advances in the biological properties of chitosan and its derivatives, as well as their applications in the prevention and treatment of oral diseases.

Anti-Infective Agents , Chitosan
Article in Chinese | WPRIM | ID: wpr-880422


It is well known that chitosan-based composites are widely used in implantable medical devices. The development of chitosan-based composite materials with different types was summarized in this paper, such as inorganic, organic and composite phases. Then, combined with the research focus, the development of 3D printing technology and chitosan-based composites was summarized. It was also pointed out that the existing problems in our research, which need to be solved urgently. At last, the development direction and broad application prospect of chitosan-based composites were prospected. And we look forward to providing reference for relevant research.

Biocompatible Materials , Chitosan , Printing, Three-Dimensional , Prostheses and Implants
Article in Chinese | WPRIM | ID: wpr-880158


OBJECTIVE@#To observe and compare the therapeutic effects of hydroxypropyl chitosan ferrous ion complex solution and ferrous sulfate solution in iron deficiency anemia rats and their effects on gastric mucosa.@*METHODS@#Seven rats were randomly selected from thirty five SPF grade SD rats as control group, and were fed with normal diet, distilled water (E). The rest of SD rats were fed with low iron feed and distilled water plus continuous tail vein bloodletting to establish the iron deficiency anemia model. After the model was established successfully, the rats were randomly divided into four groups: blank control group (A), iron deficiency anemia control group (B), ferrous sulfate group (C), hydroxypropyl chitosan ferrous ion complex (HPCTS-Fe@*RESULTS@#After modeling, except the normal control group, the hair color of the rats in the four groups showed dark yellow and the belly of the toes became white gradually. HGB, HCT, Ret%, MCV, MCH, MCHC and SF decreased significantly (P < 0.05). After treatment, the rats with dark yellow hair in group C and D were improved, and the toe abdomen turned pink gradually. RBC, HGB, HCT, Ret%, MCV, MCH, MCHC and SF in rats in group C and D increased, which were higher than those in group B (P < 0.05). The HGB of the rats in group D was higher than that of group C in day 28th during treatment and the Ret% was higher than that in group C at day 10th (P<0.05).After treatment, the liver and spleen of the rats in group C and D were lighter than those in group B (P<0.05).The gastric mucosa in group A, B, D and E was not damaged obviously, while it was slightly irritated and damaged in group C.@*CONCLUSION@#Hydroxypropyl chitosan ferrous complex solution can improve the hemoglobin level of SD rats with iron deficiency anemia, which is stronger than ferrous sulfate solution and shows no damage to gastric mucosa.

Anemia, Iron-Deficiency/drug therapy , Animals , Chitosan , Ferrous Compounds , Hemoglobins , Iron , Rats , Rats, Sprague-Dawley
Braz. J. Vet. Res. Anim. Sci. (Online) ; 58: e179885, 2021. ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-1347989


Hydroxyapatite, chitosan, and carbon nanotube composite biomaterial were developed to improve bone healing. Previous studies suggested that a combination of biomaterials and mesenchymal stem cells (MSCs) can potentially help promote bone regeneration. In the present study, we first developed hydroxyapatite, chitosan, and carbon nanotube composite biomaterial. Then, the effect of different concentrations of the extract on the viability of Vero cells (ATCC CCL-81) and MSCs obtained from sheep bone marrow using methylthiazol tetrazolium (MTT) and propidium iodide (PI) assays were evaluated. The biomaterial group demonstrated an absence of cytotoxicity, similar to the control group. Samples with 50% and 10% biomaterial extract concentrations showed higher cell viability compared to samples from the control group (MTT assay). These results suggest that the presence of this composite biomaterial can be used with MSCs. This study also concluded that hydroxyapatite, chitosan, and carbon nanotube composite biomaterial were not cytotoxic. Therefore, these could be used for performing in vivo tests.(AU)

O compósito à base de hidroxiapatita, quitosana e nanotubo de carbono foi desenvolvido com o intuito de auxiliar na consolidação óssea. Estudos anteriores sugerem que a combinação de substitutos ósseos e células-tronco mesenquimais (CTM) podem auxiliar a potencializar e promover a regeneração óssea. No presente estudo, o biomaterial foi desenvolvido e a viabilidade e a citotoxicidade de células Vero (ATCC CCL-81) e CTM obtidas de medula óssea provenientes de ovinos utilizando ensaios metil-tiazol-tetrazólio, MTT e iodeto de propídeo (PI) foram avaliadas em diferentes concentrações de extrato desse compósito. O compósito demonstrou ausência de citotoxicidade com comportamento semelhante ao grupo controle. Amostras com 50% e 10% de concentração de extrato do compósito mostraram resultados maiores comparados ao grupo controle (ensaio MTT). Esses resultados também sugerem que a presença do biomaterial pode ser utilizada em associação a CTM. Assim, esse estudo conclui que o compósito apresentado de hidroxiapatita, quitosana e nanotubo de cabono não foi considerado citotóxico e pode ser utilizado em teste in vivo.(AU)

Animals , Biocompatible Materials , Durapatite , Chitosan , Cytotoxicity, Immunologic , Nanotubes, Carbon , Mesenchymal Stem Cells
Braz. dent. sci ; 24(2): 1-9, 2021. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1177832


Objective: To assess the shear bond strength (SBS) of resin composite to deep dentin, using 1 and 2.5% chitosan pretreatment as well as different adhesive systems. Material and Methods: 80 human maxillary molars were randomly divided to eight groups according to the type of adhesive system and dentin pretreatment (n = 10): I) two-step self-etch system (Clearfil SE bond); II) two-step etch-and-rinse system (Adper single bond 2); III) 2.5% chitosan + Clearfil SE bond; IV) 2.5% chitosan +etch + Adper single bond 2; V) etch + 2.5% chitosan + Adper single bond 2; VI) 1% chitosan + Clearfil SE bond; VII) 1% chitosan + etch + Adper single bond 2; VIII) etch + 1% chitosan + Adper single bond 2 (chitosan solution (w/v): 2.5 g and 1 g of chitosan (Sigma Aldrich, USA) was dissolved in 100 ml of 1% acetic acid). Plastic molds were positioned on dentin and filled with composite (Z350, 3M ESPE, USA). SBS (MPa) was tested using a universal testing machine. ANOVA tests, Tukey's test, and independent t test were used to analyze data (p ≤ 0.05). Results: The highest SBS value among self-etch groups was observed with 1% chitosan (p = 0.001). In the etch-and-rinse group, the SBS of 1% chitosan was significantly lower than the other groups. Chitosan treatment following acid etching led to higher SBS in comparison to when chitosan was applied before etching, with the significant difference in 1% concentration (p = 0.030). A predominance of mix fractures was observed in dentin. Conclusion: Improved dentin bond strength can be achieved through immediate dentin pretreatment with 1% chitosan in self-etch adhesive systems. Chitosan Pretreatment may not be advantageous for etch-and-rinse adhesive systems. (AU)

Objetivo: Avaliar a resistência ao cisalhamento (RC) da resina composta em dentina profunda, utilizando quitosana de 1 e 2,5% como pré-tratamento, e também diferentes sistemas adesivos. Materiai e métodos: 80 molares superiores humanos foram divididos aleatoriamente em oito grupos de acordo com o tipo de sistema adesivo e pré-tratamento dentinário (n = 10): I) sistema autocondicionante de dois passos (Clearfil SE bond); II) sistema convencional de dois passos (Adper Single Bond II); III) quitosana 2,5% + Clearfil SE bond; IV) quitosana 2,5% + ácido + Adper single bond; V) ácido + quitosana 2,5% + Adper single bond II; VI) quitosana 1% + Clearfil SE bond; VII) quitosana 1% + ácido + Adper single bond II; VIII) ácido + quitosana 1% + Adper single bond II (solução de quitosana (w/w): 2,5 ge 1 g de quitosana (Sigma Aldrich, EUA) foi dissolvido em 100 ml de ácido acético a 1%). Moldeiras foram posicionados na dentina e preenchidos com resina composta (Z350, 3M ESPE, EUA). O RC (MPa) foi testado em uma máquina de teste universal. Os testes ANOVA, teste de Tukey e teste t foram usados para analisar os dados (p ≤ 0,05). Resultados: O maior valor de RC entre os grupos autocondicionantes foi observado com quitosana a 1% (p = 0,001). No grupo do condicionamento total a RC da quitosana a 1% foi significativamente menor do que nos outros grupos. O tratamento com quitosana após o condicionamento ácido levou a um maior RC em comparação a quitosana aplicada antes do condicionamento, com diferença significativa na concentração de 1% (P = 0,030). Observou-se predomínio de fraturas na dentina. Conclusão: A resistência de união à dentina pode ser alcançada por meio do pré-tratamento imediato da dentina com quitosana a 1% em sistemas adesivos autocondicionantes. O pré-tratamento com quitosana pode não ser vantajoso para sistemas adesivos de condicionamento total. (AU)

Humans , Composite Resins , Shear Strength , Dentin , Chitosan
J. appl. oral sci ; 29: e20210120, 2021. tab, graf
Article in English | LILACS | ID: biblio-1340104


Abstract Objective Our study aims to synthesize, characterize, and determine the effects of a ChNPs suspension on human enamel after cariogenic challenge via pH-cycling. Methodology ChNPs were synthesized by ion gelation and characterized by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering. Forty enamel blocks were divided into four groups (n=10/group): (i) ChNPs suspension; (ii) chitosan solution; (iii) 0.05% sodium fluoride (NaF) solution; and (iv) distilled water. Specimens were exposed to cariogenic challenge by cycling in demineralization solution (3 h) and then remineralized (21h) for 7 days. Before each demineralization cycle, the corresponding solutions were passively applied for 90 s. After 7 days, specimens were examined for surface roughness (Ra) and Knoop hardness (KHN) before and after the cariogenic challenge; % KHN change (variation between initial and final hardness), and surface topography by an optical profilometer. The data were analyzed by repeated-measures ANOVA, One-way ANOVA, and Tukey tests (α=0.05). Results TEM images showed small spherical particles with diameter and zeta potential values of 79.3 nm and +47.9 mV, respectively. After the challenge, all groups showed an increase in Ra and a decrease in KHN values. Optical profilometry indicated that ChNPs- and NaF-treated specimens showed uneven roughness interspersed with smooth areas and the lowest %KHN values. Conclusion The ChNPs suspension was successfully synthesized and minimized human enamel demineralization after a cariogenic challenge, showing an interesting potential for use as an oral formulation for caries prevention.

Humans , Tooth Demineralization/prevention & control , Chitosan , Nanoparticles , Sodium Fluoride , Cariostatic Agents , Dental Enamel , Hardness
Braz. arch. biol. technol ; 64(spe): e21200795, 2021. tab, graf
Article in English | LILACS | ID: biblio-1285573


Abstract Hesperidin is a natural compound which is found in citric fruits and presents antitumor and antimicrobial activities. However, the in vivo efficacy of Hesperidin is reduced due to its low oral bioavailability. Protein-based nanoparticles have been applied to improve biological parameters of drugs and natural compounds. Gliadin is a monomeric protein present in wheat. In this study, gliadin-based nanoparticles containing hesperidin were obtained by desolvation technique and a Taguchi orthogonal array design was employed to optimize the formulation. The independent variables were set as concentration of CaCl2 (0.5; 1 or 2%) and stabilizing agent (Pluronic F68, Tween 80 or sodium caseinate). The dependent variables consisted of mean diameter, polydispersity index, zeta potential, and encapsulation efficiency. The results showed significant effects on the dependent variables when 1% CaCl2 and Pluronic F68 were used. The optimized formulation was coated with chitosan to increase the physical stability of the nanoparticles. The final nanoparticles presented a mean diameter of 321 nm and polydispersity index of 0.217, and spherical shape. After coating, the Zeta potential was +21 mV, and the encapsulation efficiency was 73 %. The in vitro release assay showed that about 98% of the drug was released from the nanoparticles after 48 h. Moreover, the nanoparticles reduced hesperidin cytotoxicity on healthy cells (Vero cells) and improved the cytotoxicity on tumor cells (HeLa, PC-3 and Caco-2 cells). Results showed that the chitosan-coated gliadin nanoparticles are potential carriers for hesperidin delivery for cancer treatment.

Chitosan/chemistry , Gliadin/chemistry , Hesperidin/pharmacology , Neoplasms/drug therapy , Nanoparticles
Article in English | LILACS, BBO | ID: biblio-1250450


ABSTRACT Objective: To investigate the antimicrobial activity of colloidal selenium nanoparticles in chitosan solution (Cts-Se-NPs) against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. Material and Methods: Cts-Se-NPs solution was prepared using a simple chemical reduction method. The MIC and MBC against S. mutans, L. acidophilus, and C. albicans were determined using the broth dilution assay. Results: The Cts-Se-NPs had remarkable antimicrobial activity against S. mutans, L. acidophilus, and C. albicans. The MIC values of the Cts-Se-NPs were lowest for S. mutans (0.068 mg/ml) compared to L. acidophilus (0.137 mg/ml), and C. albicans (0.274 mg/ml). The MBC values of the Cts-Se-NPs against the microorganisms after one, two, six, and 24 hours indicated that the concentration of 0.274 mg/ml of Cts-Se-NPs completely killed S. mutans, L. acidophilus, and C. albicans after one, two, and six hours, respectively. At the concentration of 0.137 mg/ml, S. mutans and L. acidophilus were killed after six and 24 hours, respectively. Conclusion: These findings encourage the potential use of Cts-Se-NPs in dentistry, while further clinical research is required in this area.

Selenium , Streptococcus mutans , Dentistry , Chitosan , Nanoparticles , Candida albicans , Iran , Lactobacillus acidophilus
São José dos Campos; s.n; 2021. 54 p. ilus, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1362071


A terapia fotodinâmica (TFD) vem se mostrando como um método eficaz no controle de micro-organismos patogênicos, sendo investigada para o tratamento de diversas doenças infecciosas, como a candidose bucal. Recentemente, alguns agentes potencializadores dessa terapia têm sido estudados, incluindo a Quitosana (QT), um polímero natural extraído do exoesqueleto de crustáceos. O objetivo desse estudo foi avaliar o efeito potencializador da QT na TFD mediada pelo fotossensibilizador Azul de Metileno (AM) sobre cepas de Candida albicans, investigando sua ação em culturas planctônicas, biofilmes e células persistentes ao fluconazol. Além disso, foi avaliado a capacidade da QT em interferir na absorção do AM pelas células de Candida. Foram utilizadas duas cepas de C. albicans, sendo uma padrão (ATCC 18804) e uma clínica isolada de candidose orofaríngea (70). Para os ensaios em culturas planctônicas, as cepas de C. albicans foram cultivadas em caldo Yeast Nitrogen Base (YNB) por 24 horas. Os biofilmes foram formados por 48 horas no fundo das placas de 96 poços. Para indução de células persistentes, C. albicans foi cultivada com altas concentrações de fluconazol por 48 horas. A seguir, foram realizados os tratamentos com QT a 5 mg/mL (pH de 6,5), AM nas concentrações de 300 ou 600 µM, e irradiação com LED (660 nm) na densidade de energia de 30 J/cm2. Foram incluídos oito grupos experimentais: TFD com AM e QT na presença de Luz (AM+QT+L+), AM e QT sem Luz (AM+QT+L-), QT e Luz (QT+L+), QT sem Luz (QT+L-), TFD com AM e Luz (AM+L+), AM sem Luz (AM+L-), Solução Fisiológica com Luz (F-L+) e apenas Solução Fisiológica (F-L-). Após os tratamentos, foi realizada contagem de unidades formadoras de colônias (UFC/mL). Para determinar a absorção do fotossensibilizador pelas células de C. albicans, as células foram lisadas e centrifugadas para leitura da densidade óptica. Os dados foram analisados por ANOVA e teste de Tukey (p<0,05%). Na TFD em culturas planctônicas, o AM (300 µm) reduziu as células de Candida em 1,6 log (UFC/mL), enquanto que a associação AM+QT levou à redução de 4,7 log. Na TFD em biofilmes, ocorreu redução microbiana de 2,9 log para o tratamento com AM (600 µm) e de 5,3 log para AM+QT. Em relação às células persistentes, a redução encontrada foi de 0,8 log para AM e 1,5 log para AM+QT. No teste de absorção, a penetração do AM nas células de Candida (DO 0,02) foi aumentada na presença da QT (DO 0,39). Concluiu-se que a QT potencializou o efeito antimicrobiano da TFD em culturas planctônicas, biofilmes e células persistentes de C. albicans, provavelmente por facilitar a penetração do AM nas células fúngicas.

Photodynamic therapy (PDT) has been shown to be an effective method to control pathogenic microorganisms, being investigated for the treatment of several infectious diseases, such as oral candidiasis. Recently, some agents that enhance this therapy have been studied, including Chitosan (CS), a natural polymer extracted from the exoskeleton of crustaceans. The aim of this study was to evaluate the potentiating effect of CS on Methylene Blue (MB) photosensitizer-mediated PDT on Candida albicans strains, investigating its action on planktonic cultures, biofilms and persister cells to fluconazole. In addition, the ability of CS to interfere with MB absorption by Candida cells was evaluated. Two strains of C. albicans were used, one standard (ATCC 18804) and one isolated clinical of oropharyngeal candidosis (70). For assays in planktonic cultures, C. albicans strains were cultivated in Yeast Nitrogen Base broth (YNB) for 24 hours. Biofilms were formed for 48 hours at the bottom of 96-well plates. For the induction of persister cells, C. albicans was cultivated with high concentrations of fluconazole for 48 hours. Next, treatments were performed with CS at 5 mg/mL (pH 6.5), MB at concentrations of 300 or 600 µM, and irradiation with LED (660 nm) at an energy density of 30 J/cm2. eight experimental groups were included: PDT with MB and CS in the presence of Light (MB+CS+L+), MB and CS without Light (MB+CS+L-), CS and Light (CS+L+), CS without Light (CS +L-), PDT with MB and Light (MB+L+), MB without Light (MB+L-), Physiological Solution with Light (F-L+) and Physiological Solution only (FL-). After the treatments, colony forming units (CFU/mL) were counted. To determine the absorption of the photosensitizer by C. albicans cells, the cells were lysed and centrifuged for optical density reading. Data were analyzed by ANOVA and Tukey test (p<0.05%). In PDT in planktonic cultures, MB (300 µm) reduced Candida cells by 1.6 log (CFU/mL), while the MB+CS association led to a 4.7 log reduction. In PDT in biofilms, there was a microbial reduction of 2.9 log for the treatment with MB (600 µm) and of 5.3 log for MB+CS. Regarding persister cells, the reduction found was 0.8 log for MB and 1.5 log for MB+CS. In the absorption test, the penetration of MB into Candida cells (OD 0.02) was increased in the presence of CS (OD 0.39). It was concluded that CS potentiated the antimicrobial effect of PDT in planktonic cultures, biofilms and persister cells of C. albicans, probably by facilitating the penetration of MB into fungal cells .

Photochemotherapy , Candida albicans , Chitosan , Methylene Blue , Analysis of Variance , Photosensitizing Agents , Biofilms
Journal of Experimental Hematology ; (6): 1685-1689, 2021.
Article in Chinese | WPRIM | ID: wpr-922318


Whether in war or peace, timely, effective and accurate hemostasis is an important measure to improve the survival rate and cure rate of the wounded. All the countries in the world are actively developing different types of hemostatic materials so as to reduce the amount of bleeding in an emergency and create favorable conditions for subsequent transport and treatment. At present, the commercialized hemostatic materials are mainly divided into natural biological, synthetic biological, mineral and coagulation components, but all these materials have their own limitations. In this article, the characteristics of chitosan and its derivatives are reviewed as the representatives of the natural organic macromolecular polysaccharide hemostasis materials. Their molecular structures, biomedical properties, domestic and foreign research and application progress as well as comparison with applications of other hemostatic materials are involved. The further research is prospected for optimization and innovation to develop composite chitosan hemostatic materials with the function of hemostasis, antibiosis, pain relief and promoting wound healing.

Blood Coagulation , Chitosan/pharmacology , Hemorrhage , Hemostasis , Hemostatics , Humans
Journal of Experimental Hematology ; (6): 1478-1484, 2021.
Article in Chinese | WPRIM | ID: wpr-922282


OBJECTIVE@#To investigate the toxic damage and possible mechanism of chronic exposure of ambient particulate matter (PM@*METHODS@#Mice were treated with different doses (150, 300, 600 mg/kg) of chitosan after exposure to PM@*RESULTS@#Compared with the mice in control group, IL-2 secretion and CXCL12 expression were decreased in the bone marrow of PM@*CONCLUSION@#Chronic exposure of PM

Animals , Bone Marrow , Chitosan , Hematopoietic Stem Cell Transplantation , Hematopoietic System , Mice , Particulate Matter/toxicity
Article in English | WPRIM | ID: wpr-922755


Chitooligosaccharide-zinc (COS·Zn) is a powerful anti-oxidant and anti-aging scavenger, whose anti-oxidative ability immensely exceeds vitamin C. Therefore, this study was aimed to investigate the protective effects of COS·Zn against premature ovarian failure (POF) and potential mechanisms. Female KM adult mice were divided into the following groups: a treatment group (150 mg·kg

Animals , Chitosan , Female , Humans , Mice , NF-E2-Related Factor 2/genetics , Nuclear Proteins , Oligosaccharides , Primary Ovarian Insufficiency/drug therapy , Signal Transduction , Zinc
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2093-2100, Nov.-Dec. 2020. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1142285


A engenharia de tecidos caracteriza-se como ciência interdisciplinar, a qual vem desenvolvendo biomateriais para a regeneração do tecido ósseo no âmbito das medicinas humana e veterinária. O objetivo desta pesquisa foi avaliar a regeneração óssea obtida da aplicação do hidrogel de quitosana associado ao glicerol fosfato em falha óssea experimentalmente induzida no rádio de coelhos. Foram utilizados 15 coelhos adultos, distribuídos aleatoriamente em dois grupos, representados por cada um dos rádios de cada animal, sendo um grupo tratado com hidrogel de quitosana associado ao glicerol fosfato (grupo biomaterial - GB) e um grupo que não recebeu tratamento com o biomaterial (grupo controle - GC). Os animais foram avaliados radiograficamente, por densitometria óptica e análise histológica, nos períodos 30, 60 e 90 dias pós-operatórios. Houve superioridade estatística na média geral das avaliações radiográficas do GB (2,33±0,48) sobre o GC (1,77±0,06). As médias gerais de avaliação densitométrica do GB foram superiores às do GC, sendo 6,207±1,374 e 5,71±1,512, respectivamente. A avaliação histopatológica do GB foi superior à do GC nos períodos de 30, 60 e 90 dias. Assim, é possível afirmar que o hidrogel de quitosana constitui biomaterial de características desejáveis, promovendo consolidação óssea mais rápida e eficiente, sem causar reações adversas.(AU)

Tissue engineering is an interdisciplinary science that has been developing biomaterials for bone regeneration in medicine and veterinary medicine, following an imminent need. The aim of this study was to evaluate bone regeneration after use of chitosan hydrogel associated with glycerol phosphate in experimentally induced bone gap in the radius of rabbits. Fifteen adult rabbits were randomly distributed in two experimental groups, represented by each radius of every single animal. The animals in the Biomaterial Group (GB) were treated with a glycerol phosphate-associated chitosan hydrogel and in the Control Group (GC) they received no treatment with the biomaterial. The animals were evaluated clinically, radiographically, histologically and by optic densitometry at 30, 60 and 90 days postoperatively. There was statistical superiority in the general average of the radiographic estimates of GB (2.33 ± 0.48) over the CG (1.77 ± 0.06). The general averages of GB densitometric evaluation were higher than the CG, being 6.207 ± 1.374 and 5.71 ± 1.512, respectively. Histopathological evaluation of GB was superior to CG in periods of 30, 60 and 90 days. Chitosan hydrogel constitutes a biomaterial of desired characteristics, promoting faster and more efficient bone repair when compared to GC.(AU)

Animals , Rabbits , Radius Fractures/veterinary , Biocompatible Materials/analysis , Bone Regeneration/drug effects , Chitosan/therapeutic use , Glycerophosphates/therapeutic use
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1742-1750, Sept.-Oct. 2020. tab, ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1131554


Objetivou-se, com este estudo, avaliar o processo de cicatrização da musculatura reto-abdominal em coelhos submetidos à laparorrafia, utilizando-se o fio de sutura à base de quitosana, comparando-o aos fios de categute cromado e poliglactina 910. Foram utilizados 24 coelhos adultos, divididos aleatoriamente em quatro grupos: quitosana e categute 15 dias (QC-15dias), quitosana e categute 30 dias (QC-30 dias), quitosana e poliglactina 910 15 dias (QP-15 dias) e quitosana e poliglactina 910 30 dias (QP-30 dias). Cada grupo foi composto por seis coelhos, nos quais foram realizadas duas incisões, uma do lado direito e outra do lado esquerdo e, posteriormente, a laparorrafia, com o fio de quitosana de um lado e o categute cromado ou poliglactina 910 do outro. Realizou-se análise clínico-cirúrgica, histológica e avaliação de achados de necropsia, além de testes de citotoxicidade e de mecânica no fio de quitosana. Ele apresentou baixa resistência mecânica e citotóxica. O fio de quitosana não proporcionou uma cicatrização satisfatória em coelhos, pois desencadeou uma resposta inflamatória acentuada.(AU)

The objective of this study was to evaluate the healing process of the recto-abdominal muscles in rabbits submitted to laparorrhaphy using chitosan-based suture yarn, comparing it to chrome catgut and polyglactin 910 yarns. Twenty-four adult rabbits were divided in to four random groups: chitosan and polyglactin 910 15 days (QP-15 days) and chitosan and polyglactin 910 30 days (QC-30 days), chitosan and polyglactin 910 15 days (QP-15 days) QP-30 days). Each group consisted of six rabbits, in which two incisions were made, one on the right side and one on the left side, and later the laparorraphy with the chitosan yarn on one side and chromed catgut or polyglactin 910 on the other. Clinical-surgical, histological and necropsy findings were evaluated, as well as cytotoxicity and mechanical tests on the chitosan wire. It presented low mechanical and cytotoxic resistance. Chitosan thread did not provide satisfactory healing in rabbits, as it triggered a marked inflammatory response.(AU)

Animals , Rabbits , Polyglactin 910/analysis , Sutures/veterinary , Wound Healing , Catgut/veterinary , Chitosan , Rectum/surgery , Suture Techniques/veterinary , Laparoscopy/veterinary , Guided Tissue Regeneration/veterinary , Abdomen/surgery
Braz. j. biol ; 80(3): 631-640, July-Sept. 2020. graf
Article in English | LILACS | ID: biblio-1132427


Abstract It is a fact that the regions that cultivate the most maize crop do not have fully adequate technologies to measure productivity losses caused by irregularities in water availability. The objective of this study was to evaluate the physiological characteristics of maize hybrids tolerant (DKB 390) and sensitive (BRS 1030) to drought, at V5 growth stage and under water restriction, in order to understand the mechanisms involved in the induction of tolerance to drought by chitosan in contrasting maize genotypes. Plants were cultivated in pots at a greenhouse, and chitosan 100 ppm was applied by leaf spraying. The water restriction was imposed for 10 days and then leaf gaseous exchange and chlorophyll fluorescence were evaluated. The tolerant hybrid (DKB 390) showed higher photosynthesis, stomatal conductance, carboxylation efficiency, electron transport rate, and non-photochemical quenching when chitosan was used. Plants from tolerant genotype treated with chitosan were more tolerant to water stress because there were more responsive to the biopolymer.

Resumo As regiões que cultivam milho como cultura principal ainda não possuem tecnologias adequadas para mensurar as perdas na produtividade decorrentes na disponibilidade irregular de água. O objetivo desse estudo foi avaliar as características fisiológicas de híbridos de milho tolerante (DKB 390) e sensível (BRS1030) à seca, no estádio de crescimento V5 e sob restrição hídrica, para compreender os mecanismos envolvidos na indução de tolerância à seca pela quitosana em genótipos contrastantes. As plantas foram cultivadas vasos na casa de vegetação e a quitosana 100 ppm foi aplicada por pulverização foliar. A restrição hídrica durou 10 dias e foram avaliadas as trocas gasosas e a fluorescência da clorofila. O híbrido tolerante (DKB 390) apresentou maior fotossíntese, condutância estomática, eficiência de carboxilação, taxa de transporte de elétrons e quenching não fotoquímico quando aplicada a quitosana. As plantas do genótipo tolerante tratadas com quitosana foram mais tolerantes ao déficit hídrico porque foram mais responsivas ao biopolímero.

Zea mays , Chitosan , Photosynthesis , Stress, Physiological , Water , Plant Leaves , Droughts
Braz. dent. j ; 31(4): 385-391, July-Aug. 2020. graf
Article in English | LILACS, BBO | ID: biblio-1132314


Abstract The present study evaluated the odontogenic potential of human dental pulp cells (HDPCs) exposed to chitosan scaffolds containing calcium aluminate (CHAlCa) associated or not with low doses of simvastatin (SV). Chitosan scaffolds received a suspension of calcium aluminate (AlCa) and were then immersed into solutions containing SV. The following groups were established: chitosan-calcium-aluminate scaffolds (CHAlCa - Control), chitosan calcium-aluminate with 0.5 µM SV (CHAlCa-SV0.5), and chitosan calcium-aluminate with 1.0 µM SV (CHAlCa-SV1.0). The morphology and composition of the scaffolds were evaluated by SEM and EDS, respectively. After 14 days of HDPCs culture on scaffolds, cell viability, adhesion and spread, mineralized matrix deposition as well as gene expression of odontogenic markers were assessed. Calcium aluminate particles were incorporated into the chitosan matrix, which exhibited regular pores homogeneously distributed throughout its structure. The selected SV dosages were biocompatible with HDPCs. Chitosan-calcium-aluminate scaffolds with 1 µM SV induced the odontoblastic phenotype in the HDPCs, which showed enhanced mineralized matrix deposition and up-regulated ALP, Col1A1, and DMP-1 expression. Therefore, one can conclude that the incorporation of calcium aluminate and simvastatin in chitosan scaffolds had a synergistic effect on HDPCs, favoring odontogenic cell differentiation and mineralized matrix deposition.

Resumo O presente estudo avaliou o potencial odontogênico de células da polpa dental humana (HDPCs) em contato com scaffolds de quitosana contendo aluminato de cálcio (CHAlCa) associado ou não à baixas dosagens de sinvastatina (SV). Scaffolds de quitosana receberam uma suspensão de aluminato de cálcio e foram imersos em soluções contendo a droga. Foram estabelecidos três grupos experimentais: scaffolds de quitosana e aluminato de cálcio (CHAlCa - controle), scaffolds de quitosana-aluminato de cálcio com 0.5 µM SV (CHAlCa-SV0.5), e quitosana-aluminato de cálcio com 1.0 µM SV (CHAlCa-SV1.0). A morfologia e composição foram avaliados por MEV e EDS, respectivamente. Após 14 dias do cultivo das HDPCs sobre os scaffolds, foram avaliados a viabilidade celular, adesão e espalhamento, deposição de matriz mineralizada e expressão gênica de marcadores odontogênicos. Observou-se que as partículas de aluminato de cálcio foram incorporadas à matriz de quitosana, a qual exibiu poros regulares distribuídos por toda sua estrutura. As dosagens selecionadas de sinvastatina foram biocompatíveis com as HDPCs. A concentração de 1 µM de SV induziu intensa expressão de fenótipo odontoblástico pelas HDPCs, demonstrando aumento da deposição de matriz mineralizada e maior expressão de ALP, Col1A1 e DMP-1. Portanto, podemos concluir que a incorporação de aluminato de cálcio e sinvastatina em scaffolds de quitosana apresentou um efeito sinérgico nas HDPCs, favorecendo a diferenciação celular e deposição de matriz mineralizada.

Humans , Chitosan , Calcium , Porosity , Calcium Compounds , Aluminum Compounds , Simvastatin
Arq. bras. med. vet. zootec. (Online) ; 72(1): 208-214, Jan.-Feb. 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1088921


The aim of this study was to develop a chitosan biofilm against Salmonella enteritidis, for the conservation of fertile and table eggs. Two experiments were performed. Experiment 1: 400 specific pathogen-free table eggs were divided in a completely randomized design into four treatments, five replicates and each replicate with 20 table eggs. Experimental groups were assigned to control and 1, 5 and 10% chitosan treatment. The eggs were immersed in the chitosan solution. They were then exposed to Salmonella enteritidis and stored for 1, 24, 96 and 168h at 4ºC. The eggs were then washed with 10mL of physiological saline solution. Experiment 2: 80 specific pathogen-free fertile eggs were tested, the assays were assigned to control and 1, 5 and 10% chitosan treatment. Each treatment had 20 fertile eggs. The eggs were immersed in the chitosan solution. They were individually weighed and incubated. Egg weight, humidity loss, and hatchability (weight and length of newly hatched chicks) characteristics were assessed. In Experiment 1, comparison between treatments showed differences (P< 0.05) in the total recovered of Salmonella enteritidis on eggshell, with the lower values in 5 y 10% chitosan treatment at 96 y 168h respectively. In Experiment 2, chitosan did not show any effect on the egg weight and chick weight, where the average was 57.44 and 38.23g respectively. The humidity loss and chick length showed differences (P< 0.05), with the lower values in 5 y 10% chitosan treatment. The antibacterial activity of chitosan biofilm provide a practical tool against Salmonella enteritidis in fertile and table eggs because the chitosan did not affect egg weight and chick weight, relevant parameters in the poultry industry.(AU)

O presente estudo teve como objetivo desenvolver um biofilme de quitosana contra Salmonella enteritidis, para conservação de ovos férteis e de mesa. Dois experimentos foram realizados. Experimento 1: 400 ovos de mesa livres de patógenos especificados foram divididos em delineamento inteiramente casualizado em quatro tratamentos, cinco repetições e cada réplica contendo 20 ovos de mesa. Grupos experimentais foram designados para controle e 1, 5 e 10% de tratamento com quitosana. Os ovos foram imersos em solução de quitosana. Em seguida foram expostos a Salmonella enteritidis, e armazenados por 1, 24, 96 e 168h a 4ºC. Após, os ovos foram lavados com 10mL de solução salina fisiológica. Experimento 2: 80 ovos férteis livres de patógenos especificados foram testados. Os ensaios foram atribuídos a controle e 1, 5 e 10% de tratamento com quitosana. Cada tratamento teve 20 ovos férteis. Os ovos foram imersos em solução de quitosana. Em seguida foram individualmente pesados e incubados. Peso dos ovos, perda de umidade e características de eclodibilidade (peso e comprimento dos pintinhos recém-nascidos) foram avaliados. No Experimento 1, a comparação entre tratamentos mostrou diferenças (P< 0,05) na quantidade total recuperada de Salmonella enteritidis na casca, com os menores valores em 5 e 10% de tratamento com quitosana a 96 e 168h respetivamente. No experimento 2, a quitosana não mostrou nenhum efeito no peso do ovo e no peso do pintinho, onde a média foi de 57,44 e 38,23g respetivamente. A perda de umidade e comprimento do pintinho apresentaram diferenças (P< 0,05), com os menores valores em 5 e 10% de tratamento com quitosana. A atividade antibacteriana do biofilme de quitosana, fornece uma ferramenta prática contra Salmonella enteritidis em ovos férteis e de mesa, pois a quitosana não afetou o peso do ovo e peso do pintinho, parâmetros relevantes na indústria avícola.(AU)

Animals , Salmonella enteritidis , Salmonella Infections/prevention & control , Biofilms , Chitosan , Eggs/microbiology
Braz. j. med. biol. res ; 53(1): e8621, Jan. 2020. tab, graf
Article in English | LILACS | ID: biblio-1055482


The use of specially designed wound dressings could be an important alternative to facilitate the healing process of wounds in the hyperglycemic state. Biocompatible dressings combining chitosan and alginate can speed up wound healing by modulating the inflammatory phase, stimulating fibroblast proliferation, and aiding in remodeling phases. However, this biomaterial has not yet been explored in chronic and acute lesions of diabetic patients. The aim of this study was to evaluate the effect of topical treatment with a chitosan-alginate membrane on acute skin wounds of hyperglycemic mice. Diabetes mellitus was induced by streptozotocin (60 mg · kg-1 · day-1 for 5 days, intraperitoneally) and the cutaneous wound was performed by removing the epidermis using a surgical punch. The results showed that after 10 days of treatment the chitosan and alginate membrane (CAM) group exhibited better organization of collagen fibers. High concentrations of interleukin (IL)-1α, IL-1β, granulocyte colony-stimulating factor (G-CSF), and tumor necrosis factor-alpha (TNF-α) were detected in the first and second days of treatment. G-CSF and TNF-α level decreased after 5 days, as well as the concentrations of TNF-α and IL-10 compared with the control group (CG). In this study, the inflammatory phase of cutaneous lesions of hyperglycemic mice was modulated by the use of CAM, mostly regarding the cytokines IL-1α, IL-1β, TNF-α, G-CSF, and IL-10, resulting in better collagen III deposition. However, further studies are needed to better understand the healing stages associated with CAM use.

Animals , Male , Rabbits , Bandages , Wound Healing/drug effects , Chitosan/administration & dosage , Cell Proliferation/drug effects , Diabetes Mellitus, Experimental/physiopathology , Alginates/administration & dosage , Time Factors , Biocompatible Materials/administration & dosage , Biomarkers/blood , Collagen/drug effects , Inflammation/prevention & control , Mice, Inbred C57BL