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1.
J Biomed Mater Res B Appl Biomater ; 112(10): e35485, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39324392

RESUMEN

The development of new wound dressings made from biomaterials, which offer a better cost-benefit ratio and accelerate the healing process, is increasing nowadays. Various biopolymers can be electrospun to form functional membranes for wound healing. Therefore, in this study, chitosan and nanochitosan membranes with or without hyaluronic acid were prepared using the electrospinning technique, characterized and evaluated in the healing of skin wounds in rats. Chitosan and nanochitosan solutions, with or without hyaluronic acid, were prepared at concentrations of 1%-4% using PEO (polyethylene oxide) and subjected to the electrospinning process to obtain membranes characterized by scanning electron microscopy (SEM), mechanical tests, and antimicrobial activity. The healing effect of the membranes was evaluated by monitoring the area of the lesions, contraction of the wounds, histologic analysis, and induction of pro-inflammatory cytokine (IL-1 α and TNF-α) production in rats. The nanochitosan and nanochitosan membranes with hyaluronic acid achieved greater fiber diameter and uniformity, resistance, elasticity, and thermal stability, in addition to good adhesion to the wound bed and permeation capacity. Despite not presenting antimicrobial activity in vitro, they contributed to the production of pro-inflammatory interleukins in the animals tested, provided physical protection, reduced the wound area more markedly until the seventh day of the evaluation, with an acceleration of the healing process and especially when functionalized with hyaluronic acid. These results indicate that the membranes may be promising for accelerating the healing process of chronic wounds in humans.


Asunto(s)
Quitosano , Ácido Hialurónico , Membranas Artificiales , Piel , Cicatrización de Heridas , Quitosano/química , Quitosano/farmacología , Animales , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Cicatrización de Heridas/efectos de los fármacos , Ratas , Piel/lesiones , Piel/metabolismo , Masculino , Ratas Wistar , Vendajes
2.
Carbohydr Polym ; 346: 122640, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39245504

RESUMEN

Chitosan chemical functionalization is a powerful tool to provide novel materials for additive manufacturing strategies. The main aim of this study was the employment of computer-aided wet spinning (CAWS) for the first time to design and fabricate carboxymethyl chitosan (CMCS) scaffolds. For this purpose, the synthesis of a chitosan derivative with a high degree of O-substitution (1.07) and water soluble in a large pH range allowed the fabrication of scaffolds with a 3D interconnected porous structure. In particular, the developed scaffolds were composed of CMCS fibers with a small diameter (< 60 µm) and a hollow structure due to a fast non solvent-induced coagulation. Zn2+ ionotropic crosslinking endowed the CMCS scaffolds with stability in aqueous solutions, pH-sensitive water uptake capability, and antimicrobial activity against Escherichia coli and Staphylococcus aureus. In addition, post-printing functionalization through collagen grafting resulted in a decreased stiffness (1.6 ± 0.3 kPa) and a higher elongation at break (101 ± 9 %) of CMCS scaffolds, as well as in their improved ability to support in vitro fibroblast viability and wound healing process. The obtained results encourage therefore further investigation of the developed scaffolds as antimicrobial wound dressing hydrogels for skin regeneration.


Asunto(s)
Antibacterianos , Vendajes , Quitosano , Escherichia coli , Staphylococcus aureus , Andamios del Tejido , Cicatrización de Heridas , Quitosano/química , Quitosano/análogos & derivados , Quitosano/farmacología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Andamios del Tejido/química , Antibacterianos/farmacología , Antibacterianos/química , Animales , Ratones , Fibroblastos/efectos de los fármacos , Porosidad , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Reactivos de Enlaces Cruzados/química , Humanos
3.
Carbohydr Polym ; 344: 122496, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39218539

RESUMEN

Chitosan is a promising natural polymer for coatings, it combines intrinsic antibacterial and pro-osteoblastic properties, but the literature still has a gap from the development to behavior of these coatings, so this systematic review aimed to answer, "What is the relationship between the physical and chemical properties of polymeric chitosan coatings on titanium implants on antibacterial activity and osteoblast viability?". PRISMA guidelines was followed, the search was applied into 4 databases and grey literature, without the restriction of time and language. The selection process occurred in 2 blinded steps by the authors. The criteria of eligibility were in vitro studies that evaluated the physical, chemical, microbiological, and biological properties of chitosan coatings on titanium surfaces. The risk of bias was analyzed by the specific tool. Of 734 potential articles 10 were included; all had low risk of bias. The coating was assessed according to the technique of fabrication, FT-IR, thickness, adhesion, roughness, wettability, antibacterial activity, and osteoblast viability. The analyzed coatings showed efficacy on antibacterial activity and cytocompatibility dependent on the class of material incorporated. Thus, this review motivates the development of time-dependent studies to optimize manufacturing and allow for an increase in patents and availability on the market.


Asunto(s)
Antibacterianos , Quitosano , Materiales Biocompatibles Revestidos , Osteoblastos , Titanio , Quitosano/química , Quitosano/farmacología , Titanio/química , Titanio/farmacología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Propiedades de Superficie , Prótesis e Implantes , Animales , Supervivencia Celular/efectos de los fármacos
4.
Int J Mol Sci ; 25(18)2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39337380

RESUMEN

The rapid resistance developed by pathogenic microorganisms against the current antimicrobial pool represents a serious global public health problem, leading to the search for new antibiotic agents. The scorpion Tityus stigmurus, an abundant species in Northeastern Brazil, presents a rich arsenal of bioactive molecules in its venom, with high potential for biotechnological applications. However, venom cytotoxicity constitutes a barrier to the therapeutic application of its different components. The objective of this study was to produce T. stigmurus-venom-loaded cross-linked chitosan nanoparticles (Tsv/CN) at concentrations of 0.5% and 1.0% to improve their biological antimicrobial activity. Polymeric nanoparticles were formed with a homogeneous particle size and spherical shape. Experimental formulation parameters were verified in relation to mean size (<180 nm), zeta potential, polydispersity index and encapsulation efficiency (>78%). Tsv/CN 1.0% demonstrated an ability to increase the antimicrobial venom effect against Staphylococcus aureus bacteria, exhibiting an MIC value of 44.6 µg/mL. It also inhibited different yeast species of the Candida genus, and Tsv/CN 0.5% and 1.0% led to a greater inhibitory effect of C. tropicalis and C. parapsilosis strains, presenting MIC values between 22.2 and 5.5 µg/mL, respectively. These data demonstrate the biotechnological potential of these nanosystems to obtain a new therapeutic agent with potential antimicrobial activity.


Asunto(s)
Quitosano , Pruebas de Sensibilidad Microbiana , Nanopartículas , Venenos de Escorpión , Escorpiones , Quitosano/química , Quitosano/farmacología , Nanopartículas/química , Animales , Venenos de Escorpión/química , Venenos de Escorpión/farmacología , Escorpiones/química , Staphylococcus aureus/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Candida/efectos de los fármacos , Tamaño de la Partícula , Antibacterianos/farmacología , Antibacterianos/química , Animales Ponzoñosos
5.
Int J Biol Macromol ; 279(Pt 3): 135327, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39236955

RESUMEN

The immunoregulatory cation channel TMEM176B plays a dual role in tumor immunity. On the one hand, TMEM176B promotes antigen cross-presentation to CD8+ T cells by regulating phagosomal pH in dendritic cells (DCs). On the other hand, it inhibits NLRP3 inflammasome activation through ionic mechanisms in DCs, monocytes and macrophages. We speculated that formulating BayK8644 in PEGylated chitosan nanoparticles (NP-PEG-BayK8644) should slowly release the compound and by that mean avoid cross-presentation inhibition (which happens with a fast 30 min kinetics) while still triggering inflammasome activation. Chitosan nanocarriers were successfully obtained, exhibiting a particle size within the range of 200 nm; they had a high positive surface charge and a 99 % encapsulation efficiency. In in vitro studies, NP-PEG-BayK8644 did not inhibit antigen cross-presentation by DCs, unlike the free compound. The NP-PEG-BayK8644 activated the inflammasome in a Tmem176b-dependent manner in DCs. We administered either empty (eNP-PEG) or NP-PEG-BayK8644 to mice with established tumors. NP-PEG-BayK8644 significantly controlled tumor growth and improved mice survival compared to both eNP-PEG and free BayK8644 in melanoma and lymphoma models. This effect was associated with enhanced inflammasome activation by DCs in the tumor-draining lymph node and infiltration of the tumor by CD8+ T cells. Thus, encapsulation of BayK8644 in chitosan NPs improves the anti-tumoral properties of the compound by avoiding inhibition of antigen cross-presentation.


Asunto(s)
Inmunidad Adaptativa , Quitosano , Células Dendríticas , Inmunidad Innata , Nanopartículas , Quitosano/química , Quitosano/farmacología , Animales , Nanopartículas/química , Ratones , Inmunidad Adaptativa/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/efectos de los fármacos , Inmunidad Innata/efectos de los fármacos , Proteínas de la Membrana/inmunología , Inflamasomas/metabolismo , Línea Celular Tumoral , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Ratones Endogámicos C57BL , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Melanoma Experimental/tratamiento farmacológico , Polietilenglicoles/química , Polietilenglicoles/farmacología
6.
Int J Biol Macromol ; 279(Pt 4): 135423, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39251000

RESUMEN

Herein, four different grafted chitosans were synthesized by covalent attachment of glycine, L-arginine, L-glutamic acid, or L-cysteine to the chitosan chains. All products were subsequently permethylated to obtain their corresponding quaternary ammonium salts to enhance the inherent antimicrobial properties of native chitosan. In all cases, transparent hydrogels with the following remarkable characteristics were obtained: i) high-water absorption capacity (32-44 g H2O per g of polymer), ii) viscoelastic behavior at low deformations, iii) flexibility when subjected to deformations and iv) stability over long time scales. All the permethylated derivatives successfully inhibited 100 % of the growth of S. aureus. They also exhibited higher antimicrobial activity against E. coli than native chitosan. The structure of the chemically crosslinked products was more stable under external perturbations than that of the physically crosslinked ones. Between the chemically crosslinked products, the permethylated glutamic acid-grafted chitosan exhibited a noteworthy higher water absorption capacity with respect to that modified with cysteine, which makes it the most promising material for various industrial applications, including biomedical and food industries. Regarding biomedical applications, this derivative met the required physicochemical criteria for wound dressings, which encourages the pursuit of biological studies necessary to ensure the safety of its use for this application.


Asunto(s)
Vendajes , Quitosano , Hidrogeles , Quitosano/química , Quitosano/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Hidrogeles/síntesis química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Agua/química , Cicatrización de Heridas/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
7.
Int J Biol Macromol ; 280(Pt 4): 135995, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39326592

RESUMEN

In this work, chitosan/collagen-based membranes loaded with 2,3-dihydrobenzofuran (2,3-DHB) were developed through a simple solvent-casting procedure for use in the treatment of cutaneous Leishmaniasis. The obtained membranes were characterized by elemental analysis, FTIR, TG, DSC, and XRD. Porosity, swelling, mechanical properties, hydrophilicity, and antioxidant activity were analyzed. In addition, assessment to the biocompatibility, through fibroblasts/keratinocytes and in vitro wound healing essays were performed. The obtained results show that the new 2,3-DHB loaded chitosan/collagen membrane presented high porosity and swelling capacity as well as maximum strength, hydrophilicity, and antioxidant activity higher in relation to the control. The tests of antileishmanial activity and the AFM images demonstrate great efficacy of inhibition growth of the parasite, superior to those from the standard therapeutic agent that is currently used: Amphotericin B. The new membranes are biocompatible and stimulated the proliferation of keratinocytes. SEM images clearly demonstrate that fibroblasts were able to adhere, maintained their characteristic morphology. The healing test evidenced that the membranes have adequate environment for promoting cell proliferation and growth. As the conventional treatments often use drugs with high toxicity, the as-developed new membranes proved to be excellent candidate to treat cutaneous Leishmaniasis and can be clearly indicated for further advanced studies in vivo.


Asunto(s)
Benzofuranos , Quitosano , Colágeno , Leishmaniasis Cutánea , Quitosano/química , Quitosano/farmacología , Leishmaniasis Cutánea/tratamiento farmacológico , Leishmaniasis Cutánea/parasitología , Benzofuranos/farmacología , Benzofuranos/química , Colágeno/química , Humanos , Membranas Artificiales , Antiprotozoarios/farmacología , Antiprotozoarios/química , Fibroblastos/efectos de los fármacos , Porosidad , Animales , Cicatrización de Heridas/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Antioxidantes/farmacología , Antioxidantes/química , Queratinocitos/efectos de los fármacos
8.
J Dent ; 149: 105316, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39159744

RESUMEN

OBJECTIVES: This study assessed the effect of NaF/Chit suspensions on enamel and on S. mutans biofilm, simulating application of a mouthrinse. METHODS: The NaF/Chit particle suspensions were prepared at molar ratio [NaF]/Chitmon]≈0.68 at nominal concentrations of 0.2 % and 0.05 % NaF and characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering and zeta potential. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured. The S. mutans biofilm was formed for 7 days on eighty human enamel blocks that were divided into eight groups (n = 10/group): i) 0.05 % NaF solution; ii) 0.31 % Chit solution; iii) NaF/Chit(R=0.68) suspension at 0.05 % NaF; iv) 1.0 % HAc solution (Control); v) 0.2 % NaF solution; vi) 1.25 % Chit solution; vii) NaF/Chit(R=0.68) suspension at 0.2 % NaF; viii) 0.12 % chlorhexidine digluconate. The substances were applied daily for 90 s. S. mutans cell counts (CFU/mL) were performed, and the Knoop microhardness (KHN) of enamel samples were measured before and after biofilm formation. The KHN and CFU/mL data were analyzed by repeated measure ANOVA and Tukey's test (α = 0.05). RESULTS: Interactions between NaF and Chit were evidenced in solid state by FTIR spectra. The NaF/Chit complexes showed spontaneous microparticle formation and colloidal stability. The MIC and MBC ranged from 0.65 to 1.31 mg/mL. The NaF/Chit(R=0.68) suspension at 0.2 %NaF Group showed lower CFU/mL values than other groups. The NaF/Chit(R=0.68) suspensions Groups had the highest KHN values after biofilm formation. CONCLUSIONS: The NaF/Chit(R=0.68) complexes exhibited an antibacterial effect against S. mutans biofilm and reduced the enamel hardness loss. CLINICAL SIGNIFICANCE: The NaF/Chit(R=0.68) suspensions showed potential to be used as a mouthrinse for caries prevention.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Esmalte Dental , Pruebas de Sensibilidad Microbiana , Fluoruro de Sodio , Streptococcus mutans , Biopelículas/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Esmalte Dental/efectos de los fármacos , Esmalte Dental/microbiología , Humanos , Antibacterianos/farmacología , Fluoruro de Sodio/farmacología , Quitosano/farmacología , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Antisépticos Bucales/farmacología , Antisépticos Bucales/química , Coloides , Cariostáticos/farmacología , Cariostáticos/química
9.
Int J Biol Macromol ; 278(Pt 3): 134861, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39163960

RESUMEN

This work reports the virucidal properties of nonwoven fibers developed via electrospinning with polycaprolactone (PCL) and chitosan quaternized with phosphonium salt (NPCS), emphasizing the influence of NPCS concentration on the structure of fibers and their performance against the MHV-3 coronavirus. The addition of NPCS enhances solutions conductivity and viscosity, leading to fibers containing a finer porous structure with a more hydrophilic and smoother surface, thereby making them a potent barrier against respiratory particles, which is a key factor for protective face masks. In terms of degradation, NPCS paced-up the process, suggesting potential environmental benefits. PCL/NPCS (90/10) fibers exhibit a 99 % coronavirus inhibition within a five-minute exposure without cellular toxicity, while also meeting breathability standards for medical masks. These findings suggest the use of NPCS as a promising strategy to design materials with remarkable virucidal performance and physical characteristics that reinforce their use in the field of biomaterials engineering.


Asunto(s)
Antivirales , Quitosano , Poliésteres , Quitosano/química , Quitosano/farmacología , Poliésteres/química , Antivirales/química , Antivirales/farmacología , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos
10.
Carbohydr Res ; 543: 109220, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39038396

RESUMEN

Chitin is a polymer of N-acetylglucosamine and an essential component of the fungal cell wall. Chitosan is the deacetylated form of chitin and is also important for maintaining the integrity of this structure. Both polysaccharides are widely distributed in nature and have been shown to have a variety of applications in biomedicine, including their potential in immune sensing and as potential antifungal agents. In addition, chitin has been reported to play an important role in the pathogen-host interaction, involving innate and adaptive immune responses. This paper will explore the role of chitin and chitosan when incorporated into nanobiocomposites to improve their efficacy in detecting fungi of medical interest and inhibiting their growth. Potential applications in diagnostic and therapeutic medicine will be discussed, highlighting their promise in the development of more sensitive and effective tools for the early diagnosis of fungal infections. This review aims to highlight the importance of the convergence of nanotechnology and biology in addressing public health challenges.


Asunto(s)
Antifúngicos , Quitina , Quitosano , Hongos , Quitina/química , Quitina/farmacología , Quitosano/química , Quitosano/farmacología , Antifúngicos/farmacología , Antifúngicos/química , Hongos/efectos de los fármacos , Hongos/química , Humanos , Nanocompuestos/química , Micosis/inmunología , Micosis/tratamiento farmacológico , Micosis/diagnóstico
11.
Carbohydr Res ; 543: 109216, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39043084

RESUMEN

In this study, a series of hydrogels were synthesized from chitosan(s) that was crosslinking with glutaraldehyde at different concentrations. Ascorbic acid in an acidic medium was used to facilitate non-covalent interactions. The chitosan(s) was obtained from shrimp cytoskeleton; while ascorbic acid was extracted from xoconostle juice. The hydrogel reaction was monitored by UV-vis spectroscopy (550 nm) to determine the reaction kinetics and reaction order at 60 °C. The hydrogels structures were characterized by NMR, FT-IR, HR-MS and SEM, while the degree of cross-linking was examined with TGA-DA. The extracellular matrices were obtained as stable hydrogels where reached maximum crosslinking was of 7 %, independent of glutaraldehyde quantity added. The rheological properties showed a behavior of weak gels and a dependence of crosslinking agent concentration on strength at different temperatures. The cytotoxicity assay showed that the gels had no adverse effects on cellular growth for all concentrations of glutaraldehyde.


Asunto(s)
Materiales Biocompatibles , Quitosano , Hidrogeles , Ingeniería de Tejidos , Hidrogeles/química , Hidrogeles/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/farmacología , Quitosano/química , Quitosano/farmacología , Quitosano/síntesis química , Animales , Glutaral/química , Reología , Reactivos de Enlaces Cruzados/química
12.
Lasers Med Sci ; 39(1): 184, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39020076

RESUMEN

PURPOSE: This study aimed to investigate the efficiency of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm in the oral cavity using the photosensitizer chloroaluminum phthalocyanine encapsulated in chitosan nanoparticles (ClAlPc/Ch) at three preirradiation times. METHODS: Biofilms of Streptococcus mutans strains (ATCC 25,175) were cultivated on bovine tooth blocks and exposed to a 10% sucrose solution three times a day for 1 min over three consecutive days. The samples were randomly distributed into five treatment groups (n = 5): (I) aPDT with ClAlPc/Ch with a preirradiation time of 5 min (F5), (II) aPDT with ClAlPc/Ch with a preirradiation time of 15 min (F15), (III) aPDT with ClAlPc/Ch with a preirradiation time of 30 min (F30), (IV) 0.12% chlorhexidine digluconate (CHX), and (V) 0.9% saline solution (NaCl). After treatment, the S. mutans biofilms formed on each specimen were collected to determine the number of viable bacteria (colony-forming units (CFU)/mL). Data were analyzed for normality using the Shapiro-Wilk test and the analysis of variance (ANOVA) and Tukey HSD tests to analyze the number of viable bacteria (α = 0.05). RESULTS: The one-way ANOVA showed a difference between the groups (p = 0.0003), and the Tukey HSD posttest showed that CHX had the highest microbial reduction of S. mutans, not statistically different from the F5 and F15 groups, whereas the NaCl group had the lowest microbial reduction statistically similar to the F30 group. CONCLUSION: The results demonstrate that aPDT mediated by ClAlPc/Ch when used at preirradiation times of 5-15 min can be an effective approach in controlling cariogenic biofilm of S. mutans, being an alternative to 0.12% CHX.


Asunto(s)
Biopelículas , Quitosano , Nanopartículas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Streptococcus mutans , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/efectos de la radiación , Streptococcus mutans/fisiología , Fotoquimioterapia/métodos , Quitosano/farmacología , Quitosano/química , Nanopartículas/química , Biopelículas/efectos de los fármacos , Biopelículas/efectos de la radiación , Animales , Bovinos , Fármacos Fotosensibilizantes/farmacología , Técnicas In Vitro , Indoles/farmacología , Boca/microbiología , Clorhexidina/farmacología , Clorhexidina/análogos & derivados , Viabilidad Microbiana/efectos de los fármacos , Viabilidad Microbiana/efectos de la radiación , Compuestos Organometálicos
13.
ACS Appl Bio Mater ; 7(7): 4642-4653, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38967050

RESUMEN

Titanium-based implants have long been studied and used for applications in bone tissue engineering, thanks to their outstanding mechanical properties and appropriate biocompatibility. However, many implants struggle with osseointegration and attachment and can be vulnerable to the development of infections. In this work, we have developed a composite coating via electrophoretic deposition, which is both bioactive and antibacterial. Mesoporous bioactive glass particles with gentamicin were electrophoretically deposited onto a titanium substrate. In order to validate the hypothesis that the quantity of particles in the coatings is sufficiently high and uniform in each deposition process, an easy-to-use image processing algorithm was designed to minimize human dependence and ensure reproducible results. The addition of loaded mesoporous particles did not affect the good adhesion of the coating to the substrate although roughness was clearly enhanced. After 7 days of immersion, the composite coatings were almost dissolved and released, but phosphate-related compounds started to nucleate at the surface. With a simple and low-cost technique like electrophoretic deposition, and optimized stir and suspension times, we were able to synthesize a hemocompatible coating that significantly improves the antibacterial activity when compared to the bare substrate for both Gram-positive and Gram-negative bacteria.


Asunto(s)
Antibacterianos , Quitosano , Electroforesis , Gentamicinas , Vidrio , Ensayo de Materiales , Nanopartículas , Tamaño de la Partícula , Propiedades de Superficie , Titanio , Gentamicinas/farmacología , Gentamicinas/química , Titanio/química , Titanio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Vidrio/química , Nanopartículas/química , Quitosano/química , Quitosano/farmacología , Porosidad , Pruebas de Sensibilidad Microbiana , Humanos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Prótesis e Implantes , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
14.
Int J Biol Macromol ; 275(Pt 2): 133809, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38996893

RESUMEN

Persistent bacterial infections are the leading risk factor that complicates the healing of chronic wounds. In this work, we formulate mixtures of polyvinyl alcohol (P), chitosan (CH), collagen (C), and honey (H) to produce nanofibrous membranes with healing properties. The honey effect at concentrations of 0 % (PCH and PCHC), 5 % (PCHC-5H), 10 % (PCHC-10H), and 15 % (PCHC-15H) on the physicochemical, antibacterial, and biological properties of the developed nanofibers was investigated. Morphological analysis by SEM demonstrated that PCH and PCHC nanofibers had a uniform and homogeneous distribution on their surfaces. However, the increase in honey content increased the fiber diameter (118.11-420.10) and drastically reduced the porosity of the membranes (15.79-92.62 nm). The addition of honey reduces the water vapor transmission rate (WVTR) and the adsorption properties of the membranes. Mechanical tests revealed that nanofibers were more flexible and elastic when honey was added, specifically the PCHC-15H nanofibers with the lowest modulus of elasticity (15 MPa) and the highest elongation at break (220 %). Also, honey significantly improved the antibacterial efficiency of the nanofibers, mainly PCHC-15H nanofibers, which presented the best bacterial reduction rates against Staphylococcus aureus (59.84 %), Pseudomonas aeruginosa (47.27 %), Escherichia coli (65.07 %), and Listeria monocytogenes (49.58 %). In vitro tests with cell cultures suggest that nanofibers were not cytotoxic and exhibited excellent biocompatibility with human fibroblasts (HFb) and keratinocytes (HaCaT), since all treatments showed higher or similar cell viability as opposed to the cell control. Based on the findings, PVA-chitosan-collagen-honey nanofibrous membranes have promise as an antibacterial dressing substitute.


Asunto(s)
Antibacterianos , Vendajes , Quitosano , Colágeno , Miel , Membranas Artificiales , Nanofibras , Cicatrización de Heridas , Quitosano/química , Quitosano/farmacología , Nanofibras/química , Vendajes/microbiología , Colágeno/química , Antibacterianos/farmacología , Antibacterianos/química , Humanos , Cicatrización de Heridas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Porosidad , Alcohol Polivinílico/química , Fibroblastos/efectos de los fármacos
15.
Nitric Oxide ; 150: 37-46, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39038732

RESUMEN

The combination of nitric oxide (NO) donors with nanomaterials has emerged as a promising approach to reduce postharvest losses. The encapsulation of NO donors provides protection from rapid degradation and controlled release, enhancing the NO effectiveness in postharvest treatments. Moreover, the application method can also influence postharvest responses. In this study, two application methods were evaluated, spraying and immersion, using S-nitrosoglutathione (GSNO, a NO donor) in free and encapsulated forms on papaya fruit. Our hypothesis was that GSNO encapsulated in chitosan nanoparticles would outperform the free form in delaying fruit senescence. In addition, this study marks the pioneering characterization of chitosan nanoparticles containing GSNO within the framework of a postharvest investigation. Overall, our findings indicate that applying encapsulated GSNO (GSNO-NP-S) through spraying preserves the quality of papaya fruit during storage. This method not only minimizes weight loss, ethylene production, and softening, but also stimulates antioxidant responses, thereby mitigating oxidative damage. Consequently, it stands out as the promising technique for delaying papaya fruit senescence. This innovative approach holds the potential to enhance postharvest practices and advance sustainable agriculture.


Asunto(s)
Carica , Quitosano , Frutas , Donantes de Óxido Nítrico , S-Nitrosoglutatión , Carica/química , Donantes de Óxido Nítrico/farmacología , Donantes de Óxido Nítrico/química , Frutas/química , S-Nitrosoglutatión/farmacología , S-Nitrosoglutatión/química , Quitosano/química , Quitosano/farmacología , Estrés Oxidativo/efectos de los fármacos , Nanopartículas/química , Conservación de Alimentos/métodos
16.
Jpn J Infect Dis ; 77(5): 260-268, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-38825455

RESUMEN

Biofilm-producing methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (MR-CoNS) pose clinical challenges in treating healthcare-associated infections. As alternative antimicrobial options are needed, in this study, we aimed to determine the effect of curcumin-chitosan magnetic nanoparticles (Cur-Chi-MNP) on the biofilms of staphylococcal clinical isolates. MRSA and CoNS clinical isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing was performed using the broth microdilutions. Nanoparticles were synthesized by the co-precipitation of magnetic nanoparticles (MNP) and encapsulated by the ionotropic gelation of curcumin (Cur) and chitosan (Chi). Biofilm inhibition and eradication by nanoparticles, with and without the addition of oxacillin (OXA), were assessed in Staphylococcus strains. Cur-Chi-MNP showed antimicrobial activity against planktonic cells of MRSA and MR-CoNS strains and inhibited MRSA biofilm. The addition of OXA to Cur-Chi-MNP increased the biofilm inhibition and eradication activity against all staphylococcal strains (P = 0.0007), and higher biofilm activity was observed in the early biofilm stages. Cur-Chi-MNP showed antimicrobial and biofilm inhibitory activities against S. aureus. Addition of OXA increased biofilm inhibition and eradication activity against all staphylococcal strains. A combination treatment of Cur-Chi-MNP and OXA could potentially be used to treat staphylococcal biofilm-associated infections in the early stages before the establishment of biofilm bacterial cells.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Curcumina , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas , Biopelículas/efectos de los fármacos , Quitosano/farmacología , Quitosano/química , Curcumina/farmacología , Antibacterianos/farmacología , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Nanopartículas de Magnetita/química , Oxacilina/farmacología , Staphylococcus/efectos de los fármacos , Staphylococcus/fisiología
17.
Int J Biol Macromol ; 273(Pt 1): 133064, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38866288

RESUMEN

Bone tissue regeneration strategies have incorporated the use of natural polymers, such as hydroxyapatite (nHA), chitosan (CH), gelatin (GEL), or alginate (ALG). Additionally, platelet concentrates, such as platelet-rich fibrin (PRF) have been suggested to improve scaffold biocompatibility. This study aimed to develop scaffolds composed of nHA, GEL, and CH, with or without ALG and lyophilized PRF, to evaluate the scaffold's properties, growth factor release, and dental pulp stem cells (DPSC), and osteoblast (OB) derived from DPSC viability. Four scaffold variations were synthesized and lyophilized. Then, degradation, swelling profiles, and morphological analysis were performed. Furthermore, PDGF-BB and FGF-B growth factors release were quantified by ELISA, and cytotoxicity and cell viability were evaluated. The swelling and degradation profiles were similar in all scaffolds, with pore sizes ranging between 100 and 250 µm. FGF-B and PDGF-BB release was evidenced after 24 h of scaffold immersion in cell culture medium. DPSC and OB-DPSC viability was notably increased in PRF-supplemented scaffolds. The nHA-CH-GEL-PRF scaffold demonstrated optimal physical-biological characteristics for stimulating DPSC and OB-DPSC cell viability. These results suggest lyophilized PRF improves scaffold biocompatibility for bone tissue regeneration purposes.


Asunto(s)
Alginatos , Supervivencia Celular , Quitosano , Pulpa Dental , Durapatita , Gelatina , Osteoblastos , Fibrina Rica en Plaquetas , Células Madre , Andamios del Tejido , Humanos , Pulpa Dental/citología , Quitosano/química , Quitosano/farmacología , Gelatina/química , Fibrina Rica en Plaquetas/química , Fibrina Rica en Plaquetas/metabolismo , Andamios del Tejido/química , Células Madre/efectos de los fármacos , Células Madre/citología , Células Madre/metabolismo , Supervivencia Celular/efectos de los fármacos , Durapatita/química , Durapatita/farmacología , Alginatos/química , Alginatos/farmacología , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Adhesión Celular/efectos de los fármacos , Ingeniería de Tejidos/métodos , Células Cultivadas
18.
Dent Mater ; 40(8): 1305-1311, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38876828

RESUMEN

OBJECTIVES: This study aimed to assess antimicrobial efficacy, cytotoxicity, and cytokine release (IL-1b, IL-6, IL-10, TNF-α) from human dental pulp stem cells (hDPSCs) of chitosan (CH) and hydroxyapatite (HAp)-modified glass ionomer cements (GIC). METHODS: GICs with varied CH and HAp concentrations (0 %, 0.16 %, 2 %, 5 %, 10 %) were tested against S. mutans for 24 h or 7 days. Antimicrobial activity was measured using an MTT test. Cytotoxicity evaluation followed for optimal concentrations, analyzing mitochondrial activity and apoptosis in hDPSCs. Cytokine release was assessed with MAGPIX. Antimicrobial analysis used Shapiro-Wilk, Kruskal-Wallis, and Dunnett tests. Two-way ANOVA, Tukey, and Dunnett tests were applied for hDP metabolism and cytokine release. RESULTS: CH 2 % and HAp 5 % significantly enhanced GIC antimicrobial activity, especially after seven days. In immediate analysis, all materials showed reduced mitochondrial activity compared to the control. After 24 h, CH demonstrated mitochondrial metabolism similar to the control. All groups exhibited mild cytotoxicity (∼30 % cell death). Only IL-6 was influenced, with reduced release in experimental groups. SIGNIFICANCE: CH 2 % and HAp 5 % were most effective for antibacterial effects. GIC-CH 2 % emerged as the most promising formula, displaying significant antibacterial effects with reduced hDPSC toxicity.


Asunto(s)
Quitosano , Citocinas , Pulpa Dental , Durapatita , Cementos de Ionómero Vítreo , Quitosano/química , Quitosano/farmacología , Cementos de Ionómero Vítreo/toxicidad , Cementos de Ionómero Vítreo/farmacología , Cementos de Ionómero Vítreo/química , Humanos , Durapatita/química , Durapatita/farmacología , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Citocinas/metabolismo , Streptococcus mutans/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Ensayo de Materiales , Células Cultivadas , Células Madre/efectos de los fármacos , Apoptosis/efectos de los fármacos
19.
Int J Biol Macromol ; 271(Pt 1): 132577, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38795887

RESUMEN

Staphylococcus aureus is a pathogen widely involved in wound infection due to its ability to release several virulence factors that impair the skin healing process, as well as its mechanism of drug resistance. Herein, sodium alginate and chitosan were combined to produce a hydrogel for topical delivery of neomycin to combat S. aureus associated with skin complications. The hydrogel was formulated by combining sodium alginate (50 mg/mL) and chitosan (50 mg/mL) solutions in a ratio of 9:1 (HBase). Neomycin was added to HBase to achieve a concentration of 0.4 mg/mL (HNeo). The incorporation of neomycin into the product was confirmed by scanning electron microscopy, FTIR and TGA analysis. The hydrogels produced are homogeneous, have a high swelling capacity, and show biocompatibility using erythrocytes and fibroblasts as models. The formulations showed physicochemical and pharmacological stability for 60 days at 4 ± 2 °C. HNeo totally inhibited the growth of S. aureus after 4 h. The antimicrobial effects were confirmed using ex vivo (porcine skin) and in vivo (murine) wound infection models. Furthermore, the HNeo-treated mice showed lower severity scores than those treated with HBase. Taken together, the obtained results present a new low-cost bioproduct with promising applications in treating infected wounds.


Asunto(s)
Alginatos , Antibacterianos , Quitosano , Hidrogeles , Neomicina , Staphylococcus aureus , Quitosano/química , Quitosano/farmacología , Alginatos/química , Alginatos/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Staphylococcus aureus/efectos de los fármacos , Animales , Ratones , Neomicina/farmacología , Neomicina/química , Neomicina/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/química , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Cutáneas Estafilocócicas/tratamiento farmacológico , Infecciones Cutáneas Estafilocócicas/microbiología , Infecciones Cutáneas Estafilocócicas/patología , Portadores de Fármacos/química , Piel/efectos de los fármacos , Piel/microbiología
20.
J Dent ; 146: 105073, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38782176

RESUMEN

OBJECTIVES: Evaluate, in vitro, the effect of incorporating nano-sized sodium trimetaphosphate (TMPnano) and phosphorylated chitosan (Chi-Ph) into resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation, on mechanical, fluoride release, antimicrobial and cytotoxic properties. METHODS: RMGIC was combined with Chi-Ph (0.25%/0.5%) and/or TMPnano (14%). The diametral compressive/tensile strength (DCS/TS), surface hardness (SH) and degree of conversion (%DC) were determined. For fluoride (F) release, samples were immersed in des/remineralizing solutions. Antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism (XTT). Cytotoxicity in fibroblasts was assessed with the resazurin method. RESULTS: After 24 h, the RMGIC-14%TMPnano group showed a lower TS value (p < 0.001); after 7 days the RMGIC-14%TMPnano-0.25%Chi-Ph group showed the highest value (p < 0.001). For DCS, the RMGIC group (24 h) showed the highest value (p < 0.001); after 7 days, the highest value was observed for the RMGIC-14%TMPnano-0.25%Chi-Ph (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Chi-Ph, RMGIC-14%TMPnano-0.5%Chi-Ph showed higher and similar release of F (p > 0.001). In the SH, the RMGIC-0.25%Chi-Ph; RMGIC-0.5%Chi-Ph; RMGIC-14%TMPnano-0.5%Chi-Ph groups showed similar results after 7 days (p > 0.001). The RMGIC-14%TMPnano-0.25%Chi-Ph group showed a better effect on microbial/antibiofilm growth, and the highest efficacy on cell viability (p < 0.001). After 72 h, only the RMGIC-14%TMPnano-0.25%Chi-Ph group showed cell viability (p < 0.001). CONCLUSION: The RMGIC-14%TMPnano-0.25%Chi-Ph did not alter the physical-mechanical properties, was not toxic to fibroblasts and reduced the viability and metabolism of S. mutans. CLINICAL RELEVANCE: The addition of phosphorylated chitosan and organic phosphate to RMGIC could provide an antibiofilm and remineralizing effect on the tooth enamel of orthodontic patients, who are prone to a high cariogenic challenge due to fluctuations in oral pH and progression of carious lesions.


Asunto(s)
Antibacterianos , Biopelículas , Quitosano , Fibroblastos , Fluoruros , Cementos de Ionómero Vítreo , Ensayo de Materiales , Quitosano/farmacología , Antibacterianos/farmacología , Cementos de Ionómero Vítreo/farmacología , Cementos de Ionómero Vítreo/química , Biopelículas/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fosforilación , Fluoruros/farmacología , Dureza , Resistencia a la Tracción , Propiedades de Superficie , Fuerza Compresiva , Nanopartículas , Cementos de Resina/química , Polifosfatos/farmacología , Cementos Dentales/farmacología , Cementos Dentales/química , Supervivencia Celular/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Animales , Fosfatos/farmacología , Humanos , Soportes Ortodóncicos
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