RESUMEN
OBJECTIVE: To evaluate the possibility of improving the effectiveness of early postoperative healing in patients after surgical interventions on periodontal tissues due to the topical application of alginate plates with a complex of antimicrobial peptides and cytokines. MATERIALS AND METHODS: 40 patients who underwent periodontal surgery were examined: operations aimed at bone tissue regeneration; mucogingival operations (elimination of gum recession), corticotomy with osteoplasty, apical surgery. The patients were randomly divided into 2 groups of 20 people (main and control). At the end of the operation, alginate plates with a complex of antimicrobial peptides and cytokines were applied to the surgical intervention area to the main group. Further, 2-3 times a day, it was recommended to apply them independently for 10-14 days, after antiseptic treatment. In the control group, they were limited to double treatment with 0.05% chlorhexidine bigluconate solution daily for two weeks. Follow-up examinations and evaluation of the index of early wound healing, as well as indicators of postoperative pain, bleeding and edema were carried out on day 3, 7, 14. RESULTS: In all patients in the early postoperative period, positive dynamics of healing were observed, however, in the main group, pain indicators, as well as bleeding and swelling, according to a patient survey, were less pronounced. The early wound healing index was also more positive in the main group - on days 3, 7 and 14 there was a more intense decrease. (1.9 points.,1.5 points., 1.2 points., respectively, and in the control group 2.3 points., 2.1 points., 1.9 points.). CONCLUSION: Local application of alginate plates with a complex of antimicrobial peptides and cytokines in the early postoperative period allows to improve early wound healing after surgical interventions on periodontal tissues, and can be recommended for use at a dental appointment, as well as for use at home.
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Alginatos , Citocinas , Cicatrización de Heridas , Humanos , Alginatos/administración & dosificación , Femenino , Masculino , Cicatrización de Heridas/efectos de los fármacos , Adulto , Complicaciones Posoperatorias/prevención & control , Ácido Glucurónico/administración & dosificación , Ácidos Hexurónicos/administración & dosificación , Clorhexidina/administración & dosificación , Antiinfecciosos/administración & dosificación , Antiinfecciosos/uso terapéutico , Periodoncio/cirugía , Periodoncio/efectos de los fármacos , Adulto JovenRESUMEN
The clinical need for bone adhesives as an alternative to osteosynthesis is evident. However, this is a challenging problem due to the moist environment in surgical sites with bone surfaces covered with blood and biomolecules like lipids or proteins. A nanoparticle-loaded hydrogel that is based on a freeze-dried powder of silica-coated calcium phosphate/carboxymethyl cellulose nanoparticles (CaP/CMC/SiO2) and an aqueous solution of sodium alginate (2 wt%) was developed and optimized with respect to the gluing ability in air and in water. The final paste was crosslinked within about one minute by calcium ions released from the calcium phosphate nanoparticles and contained about 20 wt% nanoparticles and 80 wt% water. The mechanical properties of the hydrogel were determined by extensive rheological tests. The thixotropic pasty hydrogel can be applied with a syringe. The adhesion strength was about 84 kPa between moist bone fragments in air. The hydrogel kept fragments of cortical bone well connected for >3 months during complete submersion in water. Besides water, the material consists only of biocompatible and biodegradable components (calcium phosphate, CMC, alginate). It carries only a very low dose of these materials into the bone site (mainly calcium phosphate nanoparticles). In-vitro cell culture with hMSCs that differentiated to osteoblasts confirmed a good biocompatibility of the bone adhesive formulation.
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Alginatos , Cementos para Huesos , Fosfatos de Calcio , Hidrogeles , Ensayo de Materiales , Nanopartículas , Alginatos/química , Fosfatos de Calcio/química , Nanopartículas/química , Hidrogeles/química , Cementos para Huesos/química , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Materiales Biocompatibles/química , Carboximetilcelulosa de Sodio/química , Reología , Dióxido de Silicio/química , Diferenciación Celular/efectos de los fármacosRESUMEN
Matrine (MT) is a kind of alkaloid extracted from Sophora and is a promising substitute for chemical nematicides and botanical pesticides. The present study utilized sodium alginate (SA), zeolite imidazole salt skeleton (ZIF), and MT as raw materials to prepare a pH-response-release nematicide through the electrostatic spray technique. Zinc metal-organic framework (ZIF-8) was initially synthesized, followed by the successful loading of MT. Subsequently, the electrostatic spray process was employed to encapsulate it in SA, resulting in the formation of MT/ZIF-8@SA microcapsules. The efficiency of encapsulation and drug loadings can reach 79.93 and 26.83%, respectively. Soybean cyst nematode (SCN) is one of the important pests that harm crops; acetic acid produced by plant roots and CO2 produced by root respiration causing a decrease in the pH of the surrounding environment, which is most attractive to the SCN when the pH is between 4.5 and 5.4. MT/ZIF-8@SA releases the loaded MT in response to acetic acid produced by roots and acidic oxides produced by root respiration. The rate of release was 37.67% higher at pH 5.25 compared with pH 8.60. The control efficiency can reach 89.08% under greenhouse conditions. The above results demonstrate that the prepared MT/ZIF-8@SA not only exhibited excellent efficacy but also demonstrated a pH-responsive release of the nematicide.
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Alginatos , Alcaloides , Cápsulas , Glycine max , Matrinas , Quinolizinas , Electricidad Estática , Alginatos/química , Alcaloides/química , Alcaloides/farmacología , Animales , Concentración de Iones de Hidrógeno , Quinolizinas/química , Glycine max/química , Glycine max/parasitología , Cápsulas/química , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Antinematodos/química , Antinematodos/farmacología , Nematodos/efectos de los fármacos , Liberación de Fármacos , Ácido Glucurónico/química , Ácidos Hexurónicos/químicaRESUMEN
In recent years, biological 3D printing has garnered increasing attention for tissue and organ repair. The challenge with 3D-printing inks is to combine mechanical properties as well as biocompatibility. Proteins serve as vital structural components in living systems, and utilizing protein-based inks can ensure that the materials maintain the necessary biological activity. In this study, we incorporated two natural biomaterials, silk fibroin (SF) and collagen (COL), into a low-concentration sodium alginate (SA) solution to create novel composite inks. SF and COL were modified with glycidyl methacrylate (GMA) to impart photo-cross-linking properties. The UV light test and 1H NMR results demonstrated successful curing of silk fibroin (SF) and collagen (COL) after modification and grafting. Subsequently, the printability of modified silk fibroin (RSFMA)/SA with varying concentration gradients was assessed using a set of three consecutive printing models, and the material's properties were tested. The research results prove that the addition of RSFMA and ColMA enhances the printability of low-concentration SA solutions, with the Pr values increasing from 0.85 ± 0.02 to 0.90 ± 0.03 and 0.92 ± 0.02, respectively, and the mechanical strength increasing from 0.19 ± 0.01 to 0.28 ± 0.01 and 0.38 ± 0.01 MPa; cytocompatibility has also been improved. Furthermore, rheological tests indicated that all of the inks exhibited shear thinning properties. CCK-8 experiments demonstrated that the addition of ColMA increased the cytocompatibility of the ink system. Overall, the utilization of SF and COL-modified SA materials as inks represents a promising advancement in 3D-printed ink technology.
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Alginatos , Colágeno , Fibroínas , Tinta , Impresión Tridimensional , Alginatos/química , Fibroínas/química , Colágeno/química , Materiales Biocompatibles/química , Animales , Andamios del Tejido/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Ensayo de Materiales , Reactivos de Enlaces Cruzados/química , Ingeniería de Tejidos/métodos , Bioimpresión/métodos , Metacrilatos/química , HumanosRESUMEN
A simple and efficient method for obtaining monospecies and binary Staphylococcus aureus and Staphylococcus epidermidis cultures in sodium alginate gel matrix mimicking the natural microenvironment of the nasal cavity was proposed. The cultures were used for studying the effect of norepinephrine on monospecies and binary communities of two types of bacteria, S. aureus (invasive strain) and S. epidermis (commensal strain). After 24-h incubation, S. aureus predominated in the binary community, but later it was replaced by S. epidermis. Norepinephrine at higher concentrations accelerated this process without principally changing it. The model can be used to develop more effective complex antimicrobial drugs.
Asunto(s)
Alginatos , Norepinefrina , Staphylococcus aureus , Staphylococcus epidermidis , Alginatos/farmacología , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Norepinefrina/farmacología , Ácidos Hexurónicos/farmacología , Ácido Glucurónico/farmacología , Geles/farmacología , Catecolaminas/farmacología , Catecolaminas/metabolismo , Antibacterianos/farmacologíaRESUMEN
In both biological and engineered systems, polysaccharides offer a means of establishing structural stiffness without altering the availability of water. Notable examples include the extracellular matrix of prokaryotes and eukaryotes, artificial skin grafts, drug delivery materials, and gels for water harvesting. Proper design and modeling of these systems require detailed understanding of the behavior of water confined in pores narrower than about 1 nm. We use molecular dynamics simulations to investigate the properties of water in solutions and gels of the polysaccharide alginate as a function of the water content and polymer cross-linking. We find that a detailed understanding of the nanoscale dynamics of water in alginate solutions and gels requires consideration of the discrete nature of water. However, we also find that the trends in tortuosity, permeability, dielectric constant, and shear viscosity can be adequately represented using the "core-shell" conceptual model that considers the confined fluid as a continuum.
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Alginatos , Geles , Simulación de Dinámica Molecular , Agua , Alginatos/química , Agua/química , Geles/química , Soluciones , Ácidos Hexurónicos/química , Ácido Glucurónico/química , Polisacáridos/química , ViscosidadRESUMEN
Recently, nanocarriers have been utilized for encapsulating and sustained release of agrochemicals specifically auxins. Due to their potential applications such as increased bioavailability and improved crop yield and nutritional quality. Herein, the efficacy of alginate/chitosan nanocapsules as a nanocarrier for the hormone indole-3-butyric acid (IBA) loading and its effect on rooting tobacco plants has been carried out in the present study. The average particle size of IBA-alginate/chitosan nanocapsules was measured by Dynamic light scattering analysis at 321 nm. Scanning electron microscope studies revealed the spherical shape of nanoparticles with an average size of 97 nm. The average particle size of IBA-alginate/chitosan nanocapsules was measured by Dynamic light scattering analysis at 321 nm. The characteristic peaks of IBA on alginate/chitosan nanocapsules were identified by Fourier transform infrared spectroscopic analysis. Also, high efficiency (35%) of IBA hormone loading was observed. The findings indicated that the concentration of 3 mgL-1 of IBA-alginate/chitosan nanocapsules has the highest efficiency in increasing the rooting in tobacco (Nicotiana tabacum) plants compared to other treatments. According to our results, we can introduce alginate/chitosan nanocapsules as an efficient nanocarrier in IBA hormone transfer applications and their use in agriculture.
Asunto(s)
Alginatos , Quitosano , Indoles , Nanocápsulas , Nicotiana , Raíces de Plantas , Quitosano/química , Nicotiana/efectos de los fármacos , Nicotiana/crecimiento & desarrollo , Nicotiana/metabolismo , Alginatos/química , Indoles/química , Nanocápsulas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Ácidos Hexurónicos/química , Ácido Glucurónico/química , Reguladores del Crecimiento de las Plantas/farmacología , Reguladores del Crecimiento de las Plantas/químicaRESUMEN
Bone cement based on magnesium phosphate has extremely favorable properties for its application as a bioactive bone substitute. However, further improvement is still expected due to difficult injectability and high brittleness. This paper reported the preparation of novel biocomposite cement, classified as dual-setting, obtained through ceramic hydration reaction and polymer cross-linking. Cement was composed of magnesium potassium phosphate and sodium alginate cross-linked with calcium carbonate and gluconolactone. The properties of the obtained composite material and the influence of sodium alginate modification on cement reaction were investigated. Our results indicated that proposed cements have several advantages compared to ceramic cement, like shortened curing time, diverse microstructure, increased wettability and biodegradability and improved paste cohesion and injectability. The magnesium phosphate cement with 1.50% sodium alginate obtained using a powder-to-liquid ratio of 2.5 g/mL and cross-linking ratio 90/120 of GDL/CC showed the most favorable properties, with no adverse effect on mechanical strength and osteoblasts cytocompatibility. Overall, our research suggested that this novel cement might have promising medical application prospects, especially in minimally invasive procedures.
Asunto(s)
Alginatos , Cementos para Huesos , Hidrogeles , Compuestos de Magnesio , Fosfatos , Alginatos/química , Cementos para Huesos/química , Hidrogeles/química , Fosfatos/química , Compuestos de Magnesio/química , Ensayo de Materiales , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Ácido Glucurónico/química , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Animales , Reactivos de Enlaces Cruzados/química , Ácidos Hexurónicos/química , Inyecciones , Materiales Biocompatibles/químicaRESUMEN
Side effects and low efficacy of current anti-toxoplasmosis therapeutics against encysted bradyzoites necessitate research into alternative safe therapeutic options. The safety, immunostimulatory, and antimicrobial properties of alginate nanoparticle formulation (Alg-NP) highlight its potential as an oral therapy against acute toxoplasmosis. In the current study, Alg-NP was formulated and characterized and then assessed for its anti-Toxoplasma effects using parasitological, ultrastructural, immunological, and histopathological studies. Treatment with Alg-NP significantly prolonged mice survival and reduced the parasite burden in both peritoneal fluid and tissue impression smears. In addition, it altered parasite viability and caused severe tachyzoite deformities as evidenced by ultrastructural studies. Alg-NP induced high levels of serum IFN-γ in infected mice with significant amelioration in histopathological changes in both hepatic and splenic tissue sections. In conclusion, Alg-NP could be considered a promising therapeutic agent against acute murine toxoplasmosis, and owing to its safety, it could potentially be enlisted for human use.
Asunto(s)
Alginatos , Modelos Animales de Enfermedad , Nanopartículas , Toxoplasma , Toxoplasmosis Animal , Animales , Alginatos/química , Ratones , Administración Oral , Toxoplasma/efectos de los fármacos , Toxoplasmosis Animal/tratamiento farmacológico , Antiprotozoarios/farmacología , Antiprotozoarios/administración & dosificación , Antiprotozoarios/uso terapéutico , Ácido Glucurónico , Femenino , Ácidos Hexurónicos , Hígado/parasitología , Hígado/patología , Hígado/efectos de los fármacos , Bazo/efectos de los fármacos , Bazo/parasitología , Líquido Ascítico/parasitología , Carga de Parásitos , Análisis de Supervivencia , Interferón gamma/sangre , Ratones Endogámicos BALB C , Resultado del TratamientoRESUMEN
Biopolymers application in biomedical areas has been limited due to the physicochemical degradation that occurs using conventional processing/sterilization methods (e.g., steam heat, γ-radiation, ethylene oxide). Aiming to avoid/minimize degradation and preserve their properties, supercritical carbon dioxide (scCO2) has been proposed as an alternative sterilization method for such materials. ScCO2 can simultaneously be used as a drying method to produce aerogels (i) and sterilize them (ii). However, a solvent exchange is required to prepare the alcogel from hydrogel, achievable through high-pressure solvent exchange (HPSE) (iii). This study integrated three processes: HPSE, scCO2 drying, and sterilization to prepare alginate-gelatine sterilized aerogels. Two scCO2 sterilization methods were tested. Results showed that sterilization did not compromise the aerogels' chemical, thermal and swelling properties. Conversely, Young's Modulus increased, and BET surface area decreased, due to the structural changes caused by the fast pressurization/depressurization rates applied during sterilization. Regarding the sterilization efficiency, results showed a reduction in contamination throughout the process, achieving a SAL of 10-4. The sterilized aerogels were non-cytotoxic in vitro and showed improved wound-healing properties. The innovative integrated process produced decontaminated/sterile and ready-to-use aerogels reducing process time by 75 %, from 2 days up to 12 h without compromising the aerogel's properties.
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Alginatos , Dióxido de Carbono , Gelatina , Geles , Esterilización , Alginatos/química , Gelatina/química , Esterilización/métodos , Dióxido de Carbono/química , Geles/química , Animales , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/química , Ácido Glucurónico/química , Solventes/química , Ratones , Ácidos Hexurónicos/químicaRESUMEN
Lanthanide-containing luminescent hydrogels have shown potential for sensing and imaging applications. Nonetheless, integrating lanthanide ions or complexes into the polymer matrix often results in the poor stability and mechanical strength of the hydrogels. This work presents an innovative approach to fabricating luminescent hydrogels with three dynamic cross-links: imine bond, boronate ester bond, and metal-ligand coordination. Europium(III) (Eu3+) ions are incorporated into a dual-cross-linked matrix composed of phenylboronic acid-polyethylenimine-modified gelatin (PPG) and alginate dialdehyde (ADA) through a combined treatment involving freeze-drying-swelling (FDS) and freeze-thawing (FT) processes. The FDS process facilitates the formation of additional europium-carboxylate cross-links within the polymeric network to enhance its luminescence and stability, while the FT process strengthens the network physically. The impact of the FDS-FT cycle number on the microstructures and properties of PPG/ADA-Eu3+ hydrogels is thoroughly investigated, and their potential for monitoring bacterial growth and detecting copper(II) ions is also demonstrated.
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Alginatos , Gelatina , Hidrogeles , Alginatos/química , Hidrogeles/química , Gelatina/química , Europio/química , Reactivos de Enlaces Cruzados/química , Liofilización/métodos , Luminiscencia , Congelación , Ácido Glucurónico/química , Ácidos Hexurónicos/químicaRESUMEN
The present study utilizes a combination of sodium alginate (Alg), gellan gum (GG), and sodium carboxymethyl cellulose (CMC) to fabricate a ternary composite hydrogel system to encapsulate and release lactoferrin (LF). Rheological properties as well as extensive microscopy and spectroscopy characterization are performed on these materials demonstrating that the physical properties of the resultant hydrogels, such as particle size, water content, gray value, and shrinkage rate were related to the concentration of Alg. In addition, most of these hydrogels were found to have reticulated shells and inner laminar structures assembled based on hydrogen bonding and electrostatic forces. Furthermore, the encapsulation efficiency of LF in hydrogels ranged from 78.3 ± 0.3 to 83.5 ± 0.2 %. Notably, a small amount of encapsulated LF was released from the hydrogel beads in an acid environment (up to 2.2 ± 0.3 % in 2 h), while a controlled release manner was found to take place in an alkaline environment. This phenomenon indicated the potential of these hydrogels as promising matrices for bioactive compound loading and adsorption. The release mechanism varied from Alg concentration suggesting the tunable and versatile properties of this ternary composite hydrogel system. Our findings identify the potential of Alg-GG-CMC hydrogel as a delivery system suitable for various applications in the food industry.
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Alginatos , Carboximetilcelulosa de Sodio , Hidrogeles , Lactoferrina , Polisacáridos Bacterianos , Polisacáridos Bacterianos/química , Carboximetilcelulosa de Sodio/química , Alginatos/química , Hidrogeles/química , Concentración de Iones de Hidrógeno , Lactoferrina/química , Lactoferrina/administración & dosificación , Materiales Biocompatibles/química , Reología , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Sistemas de Liberación de Medicamentos/métodosRESUMEN
Polysaccharide polymers are increasingly being used as chaperon-like macromolecules in assisting protein folding of unfolded protein molecules. They interact with unfolded or partially folded proteins in a charge and conformation specific manner that results in the formation of stable protein-polysaccharide complexes. In most of the cases, the complex formation of protein-polysaccharide is driven via non-covalent interactions that have found to endorse the activity of proteins. T4L (18.7 kDa) and T7L (17 kDa) endolysins belong to the hydrolase and amidase class of peptidoglycan degrading enzymes. Both T4L and T7L exist in partially folded forms and are devoid of lytic activity at low pH conditions. In the current study, we assessed the binding of alginate with T4L and T7L at pH 7 and 3 using variety of biophysical and biochemical techniques. Spectroscopic studies revealed differential structural modulations of partially folded T4L and T7L upon their interaction with alginate. Further, the complex formation of alginate with partially folded T4L/T7L was confirmed by ITC and STEM. Additionally, the formed complexes of alginate with both T4L/T7L PF endolysins were found to be chemically and enzymatically stable. Moreover, such complexes were also marked with differential enhancement in their lytic activities at acidic pH conditions. This implied the potency of alginate as an excellent choice of matrix to preserve the structural and functional integrity of partially folded forms of T4L and T7L at highly acidic conditions.
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Alginatos , Endopeptidasas , Pliegue de Proteína , Alginatos/química , Alginatos/metabolismo , Endopeptidasas/química , Endopeptidasas/metabolismo , Proteínas Virales/química , Proteínas Virales/metabolismo , Concentración de Iones de Hidrógeno , Unión Proteica , Ácido Glucurónico/química , Bacteriófago T4/enzimología , Ácidos Hexurónicos/química , Ácidos Hexurónicos/metabolismo , Conformación ProteicaRESUMEN
In present study, whey protein isolate fibrils and sodium alginate complexes (WPIFs-SA) were prepared and further used to stabilize Pickering emulsions for lycopene delivery. The optimal interaction between WPIFs and SA occurred at pH 3.0, with a mass ratio of 2:1. Increasing the oil fractions and the content of WPIFs-SA complexes significantly improved Pickering emulsions' stability, concurrently reducing droplet size and increasing viscoelasticity. Meanwhile, it facilitated the formation of a thicker protective layer and a compact network structure around the oil droplets, offering better protection for lycopene against thermal and photo degradation. In vitro digestion studies revealed that as the oil fractions and complex contents increased, the lipolysis degree decreased. The engineered WPIFs-SA Pickering emulsion could be used as an innovative delivery system for the protection and delivery of lycopene.
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Alginatos , Emulsiones , Licopeno , Proteína de Suero de Leche , Proteína de Suero de Leche/química , Alginatos/química , Licopeno/química , Concentración de Iones de Hidrógeno , Digestión , Viscosidad , Tamaño de la Partícula , Carotenoides/química , Lipólisis , Ácido Glucurónico/química , Ácidos Hexurónicos/químicaRESUMEN
This study examined the impacts of ultrasonic power (0, 150, 300, 450, 600, and 750 W) and ultrasonic durations (3, 6, 9, 12, and 15 min) on the physicochemical properties and microstructure of diacylglycerol (DAG)-loaded emulsions stabilized with soybean protein isolate (SPI) and sodium alginate (SA). The findings indicated that the smallest particle size, zeta potential, and contact angle for SPI-SA-DAG emulsions were respectively 5.58 µm, -49.85 mV, and 48.65°, achieved at an ultrasonic power of 450 W. The emulsification properties, loss modulus, storage modulus, and apparent viscosity of the emulsions were optimal at this power setting and at a duration of 9 min. Analytical techniques, including confocal laser scanning-, scanning electron-, and atomic force microscopy, revealed that ultrasonication significantly altered emulsion aggregation state, with the surface roughness (Rq) being minimized at 450 W. These results demonstrated that the stability of SPI-SA-DAG emulsions can be effectively enhanced by an appropriate ultrasonic treatment at 450 W for 9 min. This research provides theoretical support for the broad application of sonication techniques in the food industry.
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Alginatos , Diglicéridos , Emulsiones , Proteínas de Soja , Alginatos/química , Proteínas de Soja/química , Diglicéridos/química , Sonicación , Ácidos Hexurónicos/química , Ácido Glucurónico/química , Fenómenos Químicos , Tamaño de la Partícula , Ondas UltrasónicasRESUMEN
PURPOSE: to evaluate biocompatibility and osteogenic potential of hydroxyapatite/alginate composite after its implantation on rat calvarian critical bone defect. METHODS: thirty adults male Wistar rats were randomly distributed into two groups: GHA - critical bone defect filled with hydroxyapatite/alginate composite granules (HA/Alg) and CG - critical bone defect without biomaterial; evaluated at biological points of 15, 45 and 120 days. RESULTS: the histomorphometrically analyses for GHA showed osteoid matrix deposition (OM) among the granules and towards the center of the defect in centripetal direction throughout the study, with evident new bone formation at 120 days, resulting in filling 4/5 of the initial bone defect. For CG, this finding was restricted to the edges of the bone margins and formation of connective tissue on the residual area was found in all biological points. Inflammatory response on GHA was chronic granulomatous type, discrete and regressive for all biological points. Throughout the study, the CG presented mononuclear inflammatory infiltrate diffuse and regressive. Histomorphometry analyses showed that OM percentage was evident for GHA group when compared to CG group in all analyzed periods (p > 0.05). CONCLUSIONS: the biomaterial evaluated at this study showed to be biocompatible, bioactive, osteoconductive and biodegradable synchronously with bone formation.
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Alginatos , Materiales Biocompatibles , Regeneración Ósea , Sustitutos de Huesos , Durapatita , Ensayo de Materiales , Ratas Wistar , Animales , Masculino , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Alginatos/farmacología , Durapatita/farmacología , Durapatita/uso terapéutico , Materiales Biocompatibles/uso terapéutico , Sustitutos de Huesos/uso terapéutico , Distribución Aleatoria , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ácidos Hexurónicos/farmacología , Ácido Glucurónico/farmacología , Cráneo/cirugía , Cráneo/efectos de los fármacos , Factores de Tiempo , Ratas , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: Bacterial cellulose (BC) has shown high capacity for the treatment of wounds and burns, providing a moisty environment. Calcium alginate can be associated with BC to create gels that aid in wound debridement and contribute to appropriate wound healing. This study is aimed at characterizing and evaluating the use of bacterial cellulose/alginate gel in skin burns in rats. METHODS: Cellulose and cellulose/alginate gels were compared regarding the capacity of liquid absorption, moisture, viscosity, and potential cytotoxicity. The 2nd degree burns were produced using an aluminum metal plate (2.0cm) at 120ºC for 20s on the back of rats. The animals were divided into non-treated, CMC(Carboxymethylcellulose), Cellulose(CMC with bacterial cellulose), and Cellulose/alginate(CMC with bacterial cellulose and alginate). The animals received topical treatment 3 times/week. Biochemical (MPO, NAG and oxidative stress), histomorphometry and immunohistochemical assays (IL-1ß IL-10 and VEGF) were conducted on the 14th, 21st, 28th, and 35th days. RESULTS: Cellulose/Alginate gel showed higher absorption capacity and viscosity compared to Cellulose gel, with no cytotoxic effects. Cellulose/alginate presented lower MPO values, a higher percentage of IL-10, with greater and balanced oxidative stress profile. CONCLUSIONS: The use of cellulose/alginate gel reduced neutrophils and macrophage activation and showed greater anti-inflammatory response, which can contribute to healing chronic wounds and burns.
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Alginatos , Quemaduras , Celulosa , Hidrogeles , Ratas Wistar , Cicatrización de Heridas , Animales , Alginatos/uso terapéutico , Celulosa/uso terapéutico , Quemaduras/tratamiento farmacológico , Quemaduras/terapia , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/uso terapéutico , Masculino , Ratas , Ácido Glucurónico/uso terapéutico , Ácidos Hexurónicos/uso terapéutico , Reproducibilidad de los Resultados , Viscosidad , Estrés Oxidativo/efectos de los fármacos , Inmunohistoquímica , Factores de Tiempo , Piel/lesiones , Piel/efectos de los fármacosRESUMEN
Calcined bone is an attractive natural material for use as a bone substitute because of its cost-effectiveness and high biocompatibility, which are comparable to that of synthetic hydroxyapatite. However, the calcination process has significantly weakened the mechanical properties. In this study, a composite of calcined bovine bone powder reinforced with silane cross-linked alginate was prepared to assess its biocompatibility, osteoconductivity, and mechanical compatibility as a bone substitute material. Culture studies with osteoblast-like cells (MC3T3-E1) showed no cytotoxicity toward the composite and exhibited general cell proliferative properties in its presence. In contrast, the composite reduced the alkaline phosphatase activity of osteoblasts but led to significant noncellular apatite deposition on the surface. In addition, quasi-static compression tests of the composite revealed mechanical properties comparable to those of human cancellous bone. The mechanical properties remained stable under wet conditions and did not deteriorate significantly even after 2 weeks of immersion in simulated body fluid at 37°C. The results show that this composite, composed of calcined bone powder and silane cross-linked alginate, is a promising bone substitute material with biocompatibility, osteoconductivity, and mechanical compatibility.
Asunto(s)
Alginatos , Sustitutos de Huesos , Ensayo de Materiales , Osteoblastos , Silanos , Alginatos/química , Animales , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Ratones , Bovinos , Osteoblastos/metabolismo , Osteoblastos/citología , Silanos/química , Humanos , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Polvos , Reactivos de Enlaces Cruzados/química , Línea CelularRESUMEN
Biofilms formed by Pseudomonas aeruginosa and Staphylococcus aureus, along with their antibiotic tolerance have posed challenges to treatment strategies for lung, wound, and other infections, particularly when co-infecting. In the present study, the inhibitory effect of xylitol on biofilm formation, as well as its eradication potential on pre-established biofilms formed by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and a mix of both species in an alginate bead model were tested. Xylitol concentrations of 2, 1, and 0.5 M reduced biofilm formation by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and the mixed-species biofilm in a concentration-dependent manner. Additionally, biofilms formed by these species were subjected to treatment with xylitol. Xylitol was also capable of eradicating biofilms established by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and the mixed-species biofilm by at least 20%, with the most effective eradication observed for P. aeruginosa strain PAO1. The present study indicates the effectiveness of xylitol as both an inhibitory and eradicating agent against biofilms formed by P. aeruginosa strain PAO1, methicillin-resistant S. aureus, and a mix of both species in an alginate bead model, which mimics the in vivo characteristics of P. aeruginosa aggregates.
Asunto(s)
Alginatos , Antibacterianos , Biopelículas , Staphylococcus aureus Resistente a Meticilina , Pseudomonas aeruginosa , Xilitol , Biopelículas/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Alginatos/farmacología , Xilitol/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/fisiología , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Ácido Glucurónico/farmacología , Ácidos Hexurónicos/farmacologíaRESUMEN
The maintenance and expansion of human neural stem cells (hNSCs) in 3D tissue scaffolds is a promising strategy in producing cost-effective hNSCs with quality and quantity applicable for clinical applications. A few biopolymers have been extensively used to fabricate 3D scaffolds, including hyaluronic acid, collagen, alginate, and chitosan, due to their bioactive nature and availability. However, these polymers are usually applied in combination with other biomolecules, leading to their responses difficult to ascribe to. Here, scaffolds made of chitosan, alginate, hyaluronic acid, or collagen, are explored for hNSC expansion under xeno-free and chemically defined conditions and compared for hNSC multipotency maintenance. This study shows that the scaffolds made of pure chitosan support the highest adhesion and growth of hNSCs, yielding the most viable cells with NSC marker protein expression. In contrast, the presence of alginate, hyaluronic acid, or collagen induces differentiation toward immature neurons and astrocytes even in the maintenance medium and absence of differentiation factors. The cells in pure chitosan scaffolds preserve the level of transmembrane protein profile similar to that of standard culture. These findings point to the potential of using pure chitosan scaffolds as a base scaffolding material for hNSC expansion in 3D.