RESUMEN

The aim of this study was to develop a mixture of dimethacrylate isomers (PG6EMA) as a potential monomer for dental adhesives and composites. PG6EMA was synthesized de novo and characterized in the presence of ethanol (3%, 6% or 9%). BisGMA/TEGDMA (BTEG, 50/50 wt.%) was used as the resin control. Composites were formulated with 60 wt.% of either PG6EMA or BisGMA (40 wt.% TEGDMA and 70 wt.% filler). DMPA (0.2 wt.%) and DPI-PF6 (0.4 wt.%) were added as photoinitiators, irradiated with a mercury arc lamp (320-500 nm, 500 mW/cm2; Acticure). All materials were tested for polymerization kinetics (near-infrared), viscosity (η) and storage modulus (G', oscillatory rheometry). The composites were further characterized for water sorption/solubility, wet/dry flexural strength/modulus and polymerization stress. Data were analyzed with one-way ANOVA/Tukey's test (α = 0.05). The PG6EMA resins showed lower rates of polymerization compared with BTEG (p = 0.001) but high degrees of conversion (p = 0.002). Solvent concentration did not affect RPMAX but the 6% and 9% mixtures showed higher final DC, likely due to reduced viscosity. PG6EMA had much higher viscosity than BTEG (p <0.001) and lower G' (p = 0.003). Composites modified with PG6EMA have slower polymerization rates (p = 0.001) but higher final DC (p = 0.04) than the control. PG6EMA/TEGDMA showed lower dry/wet flexural strength and comparable dry modulus. The PG6EMA/TEGDMA composite showed a 18.4% polymerization stress reduction compared to the BTEG composite. Both base monomers had similar WS/SL and G'. Within its limitations, this study demonstrated that the newly synthesized PG6EMA was a viable alternative to BisGMA in dental composites.

Asunto(s)

Bisfenol A Glicidil Metacrilato , Resinas Compuestas , Ensayo de Materiales , Metacrilatos , Polimerizacion , Ácidos Polimetacrílicos , Resinas Compuestas/química , Resinas Compuestas/efectos de la radiación , Bisfenol A Glicidil Metacrilato/química , Metacrilatos/química , Viscosidad , Ácidos Polimetacrílicos/química , Análisis de Varianza , Factores de Tiempo , Reproducibilidad de los Resultados , Valores de Referencia , Resistencia Flexional , Polietilenglicoles/química , Propiedades de Superficie , Solubilidad , Cinética , Reología , Cementos Dentales/química , Curación por Luz de Adhesivos Dentales/métodos

RESUMEN

OBJECTIVES: To analyze the incorporation of cardanol trimethacrylate monomer (CTMA), derived from the cashew nut shell liquid, as a substitute for Bis-GMA in acrylic resins formulations and its effect on experimental resin composites' physicochemical and mechanical properties. MATERIALS AND METHODS: The intermediary cardanol epoxy was synthesized via cardanol epoxidation, followed by the synthesis of CTMA through methacrylic anhydride solvent-free esterification. Experimental resin composites were formulated with an organic matrix composed of Bis-GMA/TEGDMA (50/50 wt %) (control). CTMA was gradually added to replace different proportions of Bis-GMA: 10 wt % (CTMA-10), 20 wt % (CTMA-20), 40 wt % (CTMA-40), and 50 wt % (CTMA-50). The composites were characterized by degree of conversion, water sorption and solubility, viscosity, thermogravimetric analysis, dynamic mechanical analysis, flexural strength and elastic modulus. Data were analyzed with one-way ANOVA and Tukey's post-hoc test (α = 0.05), except for water sorption data, which were analyzed by Kruskall-Wallis and Dunn's method. RESULTS: CTMA-based and control composites did not show statistically significant differences regarding degree of conversion, flexural strength and elastic modulus. CTMA reduced the viscosity and solubility compared to the Bis-GMA-based composite. The CTMA-40 and CTMA-50 exhibited significantly lower water sorption compared to the control. Also, acceptable thermal stability and viscoelastic properties were obtained for safe use in the oral cavity. CONCLUSIONS: Incorporating CTMA into composites resulted in similar chemical and mechanical properties compared to Bis-GMA-based material while reducing viscosity, water sorption and solubility. CLINICAL RELEVANCE: CTMA could be used as a trimethacrylate monomer replacing Bis-GMA in resin composites, thereby minimizing BPA exposure.

Asunto(s)

Bisfenol A Glicidil Metacrilato , Resinas Compuestas , Resistencia Flexional , Ensayo de Materiales , Fenoles , Ácidos Polimetacrílicos , Solubilidad , Resinas Compuestas/química , Bisfenol A Glicidil Metacrilato/química , Fenoles/química , Viscosidad , Ácidos Polimetacrílicos/química , Módulo de Elasticidad , Metacrilatos/química , Termogravimetría , Polietilenglicoles/química , Anacardium/química

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

RESUMEN

OBJECTIVE: this study sought to evaluate the effect of isobornyl methacrylate (IBOMA) as a diluent monomer on the physicochemical properties of experimental flowable resin composites. METHODOLOGY: the organic resin matrix of a modal flowable resin composite was formulated with 50 wt.% of bisphenol-A-glycidyl methacrylate (Bis-GMA) and 50 wt.% of a diluent monomer, in which IBOMA was used as a combining or substituent diluent monomer to triethylene glycol dimethacrylate (TEGDMA). The resin matrices were filled with 55 wt.% particles, of which 10 wt.% was 0.05-µm fumed silica, and 45 wt.% was 0.7-µm BaBSiO2 glass. Polymerization shrinkage stress (PSS; n=10), degree of conversion (DC; n=3), maximum rate of polymerization (Rpmax; n=3), film thickness (FT; n=10), sorption (Wsp; n=10), solubility (Wsl; n=10), flexural strength (FS; n=10), flexural modulus (FM; n=10), Knoop microhardness (KH; n=10), and microhardness reduction after chemical softening (HR; n=10) were evaluated. Data were analyzed using one-way ANOVA, followed by Tukey's test (α=0.05; ß=0.2). RESULTS: the results showed that the substitution or addition of IBOMA reduced FT (p=0.001), PSS (p=0.013), Rpmax (p=0.001), DC (p=0.001), FM (p=0.006) Wsp (p=0.032), and Wsl (p=0.021). However, when used as a complete substituent, IBOMA demonstrated significantly lower FS (p=0.017) and KH (p=0.008), while TEGDMA demonstrated significantly lower HR (p=0.022). CONCLUSION: the flowable composite containing IBOMA combined with TEGDMA showed no effect in KH and FS and effectively reduced the PSS, RP, FT, Wsp, and Wsl. However, it showed a reduction in DC, FS, and an increase in HR.

Asunto(s)

Bisfenol A Glicidil Metacrilato , Resinas Compuestas , Resistencia Flexional , Ensayo de Materiales , Metacrilatos , Polietilenglicoles , Polimerizacion , Ácidos Polimetacrílicos , Solubilidad , Propiedades de Superficie , Resinas Compuestas/química , Metacrilatos/química , Ácidos Polimetacrílicos/química , Polietilenglicoles/química , Bisfenol A Glicidil Metacrilato/química , Análisis de Varianza , Reproducibilidad de los Resultados , Valores de Referencia , Factores de Tiempo , Pruebas de Dureza , Dióxido de Silicio/química

RESUMEN

OBJECTIVE: To formulate an experimental methacrylate-based photo-polymerizable resin for 3D printing with ytterbium trifluoride as filler and to evaluate the mechanical, physicochemical, and biological properties. METHODS: Resin matrix was formulated with 60 wt% UDMA, 40 wt% TEGDMA, 1 wt% TPO, and 0.01 wt% BHT. Ytterbium Trifluoride was added in concentrations of 1 (G1 %), 2 (G2 %), 3 (G3 %), 4 (G4 %), and 5 (G5 %) wt%. One group remained without filler addition as control (GC). The samples were designed in 3D builder software and printed using a UV-DLP 3D printer. The samples were ultrasonicated with isopropanol and UV cured for 60 min. The resins were tested for degree of conversion (DC), flexural strength, Knoop microhardness, softening in solvent, radiopacity, colorimetric analysis, and cytotoxicity (MTT and SRB). RESULTS: Post-polymerization increased the degree of conversion of all groups (p < 0.05). G2 % showed the highest DC after post-polymerization. G2 % showed no differences in flexural strength from the G1 % and GC (p > 0.05). All groups showed a hardness reduction after solvent immersion. No statistical difference was found in radiopacity, softening in solvent (ΔKHN%), colorimetric spectrophotometry, and cytotoxicity (MTT) (p > 0.05). G1 % showed reduced cell viability for SRB assay (p < 0.05). SIGNIFICANCE: It was possible to produce an experimental photo-polymerizable 3D printable resin with the addition of 2 % ytterbium trifluoride as filler without compromising the mechanical, physicochemical, and biological properties, comparable to the current provisional materials.

Asunto(s)

Dureza , Ensayo de Materiales , Metacrilatos , Impresión Tridimensional , Metacrilatos/química , Resistencia Flexional , Polimerizacion , Polietilenglicoles/química , Resinas Compuestas/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Colorimetría , Propiedades de Superficie

RESUMEN

The use of photothermal processes has been proven effective in the control of microbial infections. Simultaneously, the localized surface plasmon resonance phenomena in metallic nanoparticles have been explored as an alternative strategy to achieve highly efficient localized heating. In this work, we propose the use of selected nanoheaters to improve the efficiency of fungal photothermal inactivation of Candida albicans through size optimization of plasmonic gold nanorods. Here, the optical heating of polyethylene glycol coated gold nanorods of varying sizes is evaluated, both theoretically and experimentally. A size-dependent computational approach was applied to identify metallic nanorods with maximized thermal performance at 800 nm, followed by the experimental comparison of optimal and suboptimal nanoheaters. Comparison among samples show temperatures of up to 53.0 °C for 41×10 nm gold nanorods against 32.3 °C for 90×25 nm, a percentage increase of ∼63% in photothermal inactivation assessments. Our findings reveal that gold nanorods of 41×10 nm exhibit superior efficiency in near-infrared (800 nm) photothermal inactivation of fungi, owing to their higher light-thermal conversion efficiency. The identification of high performance metallic nanoheaters may lead to the reduction of the nanoparticle dose used in plasmonic-based procedures and decrease the laser exposure time needed to induce cell death. Moreover, our results provide insights to better exploit plasmonic nanoparticles on photothermal inactivation protocols.

Asunto(s)

Candida albicans , Oro , Nanopartículas del Metal , Nanotubos , Candida albicans/efectos de los fármacos , Nanotubos/química , Oro/química , Oro/farmacología , Nanopartículas del Metal/química , Resonancia por Plasmón de Superficie , Rayos Infrarrojos , Polietilenglicoles/química , Polietilenglicoles/farmacología , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos

RESUMEN

OBJECTIVE: To evaluate experimental dimethacrylate-based materials containing calcium orthophosphates or calcium silicate particles in terms of their optical, mechanical and Ca2+ release behaviour. METHODS: Dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HAp), beta-tricalcium phosphate (ß-TCP) or calcium silicate (CaSi) particles were added to a photocurable BisGMA/TEGDMA resin (1:1 in mols) at a 30 vol% fraction. Materials containing silanized or non-silanized barium glass particles were used as controls. Degree of conversion (DC) at the top and base of 2-mm thick specimens was determined by ATR-FTIR spectroscopy (n = 5). Translucency parameter (TP) and transmittance (%T) were determined using a spectrophotometer (n = 3). Biaxial flexural strength (BFS) and flexural modulus (FM) were determined by biaxial flexural testing after 24 h storage in water (n = 10). Ca2+ release in water was determined during 28 days by inductively coupled plasma optical emission spectrometry (n = 3). Statistical analysis was performed using ANOVA/Tukey test (DC: two-way; TP, %T; BFS and FM: one-way; Ca2+ release: repeated measures two-way, α = 5 %). RESULTS: CaSi and ß-TCP particles drastically reduced DC at 2 mm, TP and %T (p < 0.001). Compared to both controls, all Ca2+-releasing materials presented lower BFS (p < 0.001) and only the material with DCPD showed significantly lower FM (p < 0.05). The material containing CaSi presented the highest Ca2+ release, while among materials formulated with calcium orthophosphates the use of DCPD resulted in the highest release (p < 0.001). SIGNIFICANCE: CaSi particles allowed the highest Ca2+ release. Notwithstanding, the use of DCPD resulted in a material with the best compromise between optical behaviour, DC, strength and Ca2+ release.

Asunto(s)

Compuestos de Calcio , Fosfatos de Calcio , Ensayo de Materiales , Silicatos , Silicatos/química , Compuestos de Calcio/química , Fosfatos de Calcio/química , Espectroscopía Infrarroja por Transformada de Fourier , Durapatita/química , Resistencia Flexional , Ácidos Polimetacrílicos/química , Polietilenglicoles/química , Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Vidrio/química , Calcio/química , Espectrofotometría , Fenómenos Químicos , Dióxido de Silicio , Compuestos de Bario

RESUMEN

Liposomes functionalized with monoclonal antibodies offer targeted therapy for cancer, boasting advantages like sustained drug release, enhanced stability, passive accumulation in tumors, and interaction with overexpressed receptors on cancer cells. This study aimed to develop and characterize anti-EGFR immunoliposomes loaded with cabazitaxel and assess their properties against prostate cancer in vitro and in vivo. Using a Box-Behnken design, a formulation with soy phosphatidylcholine, 10% cholesterol, and a 1:20 drug-lipid ratio yielded nanometric particle size, low polydispersity and high drug encapsulation. Immunoliposomes were conjugated with cetuximab through DSPE-PEG-Maleimide lipid anchor. Characterization confirmed intact antibody structure and interaction with EGFR receptor following conjugation. Cabazitaxel was dispersed within the liposomes in the amorphous state, confirmed by solid-state analyses. In vitro release studies showed slower cabazitaxel release from immunoliposomes. Immunoliposomes had enhanced cabazitaxel cytotoxicity in EGFR-overexpressing DU145 cells without affecting non-tumor L929 cells. Cetuximab played an important role to improve cellular uptake in a time-dependent fashion in EGFR-overexpressing prostate cancer cells. In vivo, immunoliposomes led to significant tumor regression, improved survival, and reduced weight loss in xenograft mice. While cabazitaxel induced leukopenia, consistent with clinical findings, histological analysis revealed no evident toxicity. In conclusion, the immunoliposomes displayed suitable physicochemical properties for cabazitaxel delivery, exhibited cytotoxicity against EGFR-expressing prostate cancer cells, with high cell uptake, and induced significant tumor regression in vivo, with manageable systemic toxicity.

Asunto(s)

Cetuximab , Liberación de Fármacos , Receptores ErbB , Liposomas , Neoplasias de la Próstata , Taxoides , Ensayos Antitumor por Modelo de Xenoinjerto , Masculino , Animales , Receptores ErbB/inmunología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Humanos , Línea Celular Tumoral , Taxoides/administración & dosificación , Taxoides/farmacocinética , Taxoides/farmacología , Taxoides/química , Cetuximab/administración & dosificación , Ratones , Ratones Desnudos , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Antineoplásicos/química , Polietilenglicoles/química , Polietilenglicoles/administración & dosificación , Tamaño de la Partícula , Sistemas de Liberación de Medicamentos

RESUMEN

BACKGROUND: Folic acid (FA), a synthetically produced compound analogous to vitamin B9, also referred to as vitamin folate, is an essential compound in human health and faces challenges in stability during food processing. This study explores the incorporation of FA into carboxymethylcellulose (CMC) nanofibers using electrospinning to enhance its stability. RESULTS: In this study, optimization of both electrospinning and solution parameters facilitated the fabrication of nanofibers. Furthermore, incorporating FA into CMC/polyethylene oxide (PEO) nanofibers resulted in thinner fibers, with an average diameter of 88 nm, characterized by a flat shape and smooth surface. Fourier transform infrared spectroscopic analysis demonstrated substantial hydrogen bonding interactions between FA and the polar groups present in CMC. This interaction contributed to an encapsulation efficiency of 94.5%, with a yield exceeding 87%. Thermal analysis highlighted mutual interference between CMC and PEO, with FA enhancing the thermal stability and reducing the melting temperatures and enthalpies of PEO, while also increasing the reaction heats of CMC. The encapsulated FA remained stable in acidic conditions, with only 6% degradation over 30 days, demonstrating the efficacy of CMC/PEO nanofibers in safeguarding FA against acidic environments. Moreover, the nanofibers provided a protective barrier against UV radiation, thereby preserving the stability of FA. CONCLUSION: This study emphasizes the efficacy of CMC/PEO nanofibers as a protective matrix against FA degradation. The findings indicate that this innovative approach could significantly diversify the applications of FA in food fortification, addressing concerns regarding its vulnerability to temperature and hydrolysis reactions during food processing. © 2024 Society of Chemical Industry.

Asunto(s)

Carboximetilcelulosa de Sodio , Ácido Fólico , Nanofibras , Polietilenglicoles , Nanofibras/química , Ácido Fólico/química , Carboximetilcelulosa de Sodio/química , Polietilenglicoles/química , Estabilidad de Medicamentos , Liberación de Fármacos , Portadores de Fármacos/química , Composición de Medicamentos/métodos

RESUMEN

BACKGROUND: Diabetic neuropathy (DN) is recognized as a significant complication arising from diabetes mellitus (DM). Pathogenesis of DN is accelerated by endoplasmic reticulum (ER) stress, which inhibits autophagy and contributes to disease progression. Autophagy is a highly conserved mechanism crucial in mitigating cell death induced by ER stress. Chrysin, a naturally occurring flavonoid, can be found abundantly in honey, propolis, and various plant extracts. Despite possessing advantageous attributes such as being an antioxidant, anti-allergic, anti-inflammatory, anti-fibrotic, and anticancer agent, chrysin exhibits limited bioavailability. The current study aimed to produce a more bioavailable form of chrysin and discover how administering chrysin could alter the neuropathy induced by Alloxan in male rats. METHODS: Chrysin was formulated using PEGylated liposomes to boost its bioavailability and formulation. Chrysin PEGylated liposomes (Chr-PLs) were characterized for particle size diameter, zeta potential, polydispersity index, transmission electron microscopy, and in vitro drug release. Rats were divided into four groups: control, Alloxan, metformin, and Chr-PLs. In order to determine Chr- PLs' antidiabetic activity and, by extension, its capacity to ameliorate DN, several experiments were carried out. These included measuring acetylcholinesterase, fasting blood glucose, insulin, genes dependent on autophagy or stress in the endoplasmic reticulum, and histopathological analysis. RESULTS: According to the results, the prepared Chr-PLs exhibited an average particle size of approximately 134 nm. They displayed even distribution of particle sizes. The maximum entrapment efficiency of 90.48 ± 7.75% was achieved. Chr-PLs effectively decreased blood glucose levels by 67.7% and elevated serum acetylcholinesterase levels by 40% compared to diabetic rats. Additionally, Chr-PLs suppressed the expression of ER stress-related genes (ATF-6, CHOP, XBP-1, BiP, JNK, PI3K, Akt, and mTOR by 33%, 39.5%, 32.2%, 44.4%, 40.4%, 39.2%, 39%, and 35.9%, respectively). They also upregulated the miR-301a-5p expression levels by 513% and downregulated miR-301a-5p expression levels by 65%. They also boosted the expression of autophagic markers (AMPK, ULK1, Beclin 1, and LC3-II by 90.3%, 181%, 109%, and 78%, respectively) in the sciatic nerve. The histopathological analysis also showed that Chr-PLs inhibited sciatic nerve degeneration. CONCLUSION: The findings suggest that Chr-PLs may be helpful in the protection against DN via regulation of ER stress and autophagy.

Asunto(s)

Autofagia , Diabetes Mellitus Experimental , Neuropatías Diabéticas , Estrés del Retículo Endoplásmico , Flavonoides , Liposomas , Animales , Flavonoides/farmacología , Flavonoides/administración & dosificación , Autofagia/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Masculino , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/complicaciones , Ratas , Neuropatías Diabéticas/tratamiento farmacológico , Neuropatías Diabéticas/prevención & control , Polietilenglicoles/farmacología , Aloxano , Ratas Wistar , Ratas Sprague-Dawley

RESUMEN

OBJECTIVE: The purpose of this retrospective study was to compare accuracy of arch expansion using two different thermoplastic materials in Invisalign aligners: EX30® (Polyethylene Terephthalate Glycol, or PETG) and SmartTrack® (polyurethane). METHODS: The study sample comprised 65 adult patients consecutively treated with Invisalign from two private practices: group 1 - treated with EX30® (358 teeth) and group 2 - treated with SmartTrack® (888 teeth). Six hundred and twenty-three measurements were assessed in three digital models throughout treatment: model 1 - initial, model 2 - predicted tooth position, and model 3 - achieved position. Sixteen reference points per arch were marked and, after best alignment, 2 points per tooth were copied from one digital model to another. Linear values of both arches were measured for canines, premolars, and first molars: on lingual gingival margins and cusp tips of every tooth. Comparisons were performed by Wilcoxon and Mann-Whitney test. RESULTS: Both termoplastic materials presented significant differences between predicted and achieved values for all measurements, except for the lower molar cusp tip in the SmartTrack® group. There is no statistical difference in the accuracy of transverse expansion between these two materials. Overall accuracy for EX30® aligners in maxilla and mandible were found to be 37 and 38%, respectively; and Smarttrack® presented an overall accuracy of 56.62% in the maxilla and 68.72% in the mandible. CONCLUSIONS: It is not possible to affirm one material expands better than the other. Further controlled clinical studies should be conducted comparing SmartTrack® and EX30® under similar conditions.

Asunto(s)

Diseño de Aparato Ortodóncico , Tereftalatos Polietilenos , Poliuretanos , Técnicas de Movimiento Dental , Humanos , Estudios Retrospectivos , Adulto , Femenino , Técnicas de Movimiento Dental/instrumentación , Masculino , Poliuretanos/uso terapéutico , Polietilenglicoles , Arco Dental , Aparatos Ortodóncicos Removibles , Adulto Joven

RESUMEN

This study introduces the nanobromhexine lipid particle (NBL) platform designed for effective pulmonary drug delivery. Inspired by respiratory virus transport mechanisms, NBL address challenges associated with mucus permeation and inflammation in pulmonary diseases. Composed of low molecular weight polyethylene glycol-coated lipid nanoparticles with bromhexine hydrochloride, NBL exhibit a size of 118 ± 24 nm, a neutral zeta potential, osmolarity of 358 ± 28 mOsmol/kg, and a pH of 6.5. Nebulizing without leakage and showing no toxicity to epithelial cells, NBL display mucoadhesive properties with a 60% mucin-binding efficiency. They effectively traverse the dense mucus layer of Calu-3 cultures in an air-liquid interface, as supported by a 55% decrease in MUC5AC density and a 29% increase in nanoparticles internalization compared to non-exposed cells. In assessing immunomodulatory effects, NBL treatment in SARS-CoV-2-infected lung cells leads to a 40-fold increase in anti-inflammatory MUC1 gene expression, a proportional reduction in pro-inflammatory IL-6 expression, and elevated anti-inflammatory IL-10 expression. These findings suggest a potential mechanism to regulate the excessive IL-6 expression triggered by virus infection. Therefore, the NBL platform demonstrates promising potential for efficient pulmonary drug delivery and immunomodulation, offering a novel approach to addressing mucus permeation and inflammation in pulmonary diseases.

Asunto(s)

Pulmón , Nanopartículas , SARS-CoV-2 , Nanopartículas/administración & dosificación , Humanos , Pulmón/metabolismo , SARS-CoV-2/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Inmunomodulación , Línea Celular , Mucina-1/metabolismo , COVID-19 , Lípidos/química , Lípidos/administración & dosificación , Moco/metabolismo , Polietilenglicoles/química , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Tratamiento Farmacológico de COVID-19 , Mucina 5AC/metabolismo , Liposomas

RESUMEN

OBJECTIVES: The study aimed to assess the impact of diphenyliodonium hexafluorophosphate (DPI) on the physicochemical properties of experimental resin composites (ECRs) featuring reduced concentrations of camphorquinone (CQ)/amine. METHODS: Five concentrations of CQ (0.125, 0.25, 0.5, 0.75, and 1 mol%) with dimethylaminoethyl amine benzoate (EDAB) in a 1:2 mol% ratio (CQ:EDAB) were incorporated into a 50:50 mass% monomer blend of bisphenol glycidyl methacrylate (BisGMA) and triethyleneglycol dimethacrylate (TEGDMA). An additional 5 groups with the same CQ:EDAB concentrations had 0.5 mol% DPI added. Each resin group contained 60 wt% of 0.7 µm barium-alumino-silicate glass. Light transmission (n = 3), real-time degree of polymerization (n = 3), temperature change during polymerization (n = 5), polymerization shrinkage strain (n = 3), flexural strength, and modulus (n = 12), as well as water sorption and solubility (n = 5), were evaluated. Data were analyzed using two-way ANOVA and Tukey's post-hoc test (α = 0.05). RESULTS: Light transmission was reduced in groups containing 0.125 and 0.25 mol% of CQ without DPI. DPI increased temperature, degree and rate of polymerization, despite the reduction in CQ/amine concentration. Additionally, there was an increase in polymerization shrinkage strain, flexural strength and modulus, and a reduction in water sorption and solubility in ECRs with DPI, even with lower concentrations of CQ/EDAB. SIGNIFICANCE: DPI improved the assessed properties of composites across various concentrations of CQ/EDAB, showing the benefit of reducing the quantity of CQ used without compromising the properties and curing of the resin composites.

Asunto(s)

Resinas Compuestas , Ensayo de Materiales , Polietilenglicoles , Polimerizacion , Ácidos Polimetacrílicos , Terpenos , Resinas Compuestas/química , Terpenos/química , Polietilenglicoles/química , Ácidos Polimetacrílicos/química , Bisfenol A Glicidil Metacrilato/química , Propiedades de Superficie , Compuestos Onio/química , Poliuretanos/química , Resinas Acrílicas , Compuestos de Bifenilo , Alcanfor/análogos & derivados

RESUMEN

Serodiagnosis methods have been used as platforms for diagnostic tests for many diseases. Due to magnetic nanoparticles' properties to quickly detach from an external magnetic field and particle size effects, these nanomaterials' functionalization allows the specific isolation of target analytes, enhancing accuracy parameters and reducing serodiagnosis time. Superparamagnetic iron oxide nanoparticles (MNPs) were synthesized and functionalized with polyethylene glycol (PEG) and then associated with the synthetic Leishmaniosis epitope. This nano-peptide antigen showed promising results. Regarding Tegumentary leishmaniasis diagnostic accuracy, the AUC was 0.8398 with sensibility 75% (95CI% 50.50 - 89.82) and specificity 87.50% (95CI% 71.93 - 95.03), and Visceral leishmaniasis accuracy study also present high performance, the AUC was 0.9258 with sensibility 87.50% (95CI% 63.98 - 97.78) and specificity 87.50% (95CI% 71.93 - 95.03). Our results demonstrate that the association of the antigen with MNPs accelerates and improves the diagnosis process. MNPs could be an important tool for enhancing serodiagnosis.

Asunto(s)

Ensayo de Inmunoadsorción Enzimática , Polietilenglicoles , Sensibilidad y Especificidad , Humanos , Ensayo de Inmunoadsorción Enzimática/métodos , Polietilenglicoles/química , Antígenos de Protozoos/inmunología , Leishmaniasis/diagnóstico , Nanopartículas Magnéticas de Óxido de Hierro/química , Anticuerpos Antiprotozoarios/sangre

RESUMEN

OBJECTIVE: To evaluate the influence of the barium glass (BG) filler in 3D printing resin-based composites for restorative structures. METHODS: Experimental 3D printing resin-based composites were formulated with UDMA 70%wt, Bis-EMA 20%wt, and TEGDMA 10%wt. Photoinitiators TPO and DFI (2%wt) were used. BG was incorporated at 40%wt and 50%wt. 0%wt BG was used as negative control and the VarseoSmile Crownplus (Bego) was used as a commercial control. Specimens were printed using a 3D printer. Subsequently, specimens were washed and submitted to post-curing with 405 nm at 60ºC for 2 × 20 min at FormCure (FormLabs). 3D printing resin-based composites were evaluated by flexural strength, degree of conversion, softening in solvent, radiopacity, and cytotoxicity against gingival fibroblasts. Data were statistically analyzed using one-way ANOVA (α = 0.05). RESULTS: No significant differences in flexural strength were showed between BG40% (90.5 ± 5,4 MPa), BG50% (102.0 ± 11.7 MPa) and VA (105.2 ± 11.7 MPa). Addition of 40% and 50% of BG showed no influence in the degree of conversion compared to VA (p > 0.05). All groups showed softening in solvent after immersion in ethanol (p < 0.05). All groups showed more than 1mmAl of radiopacity. BG50% showed significantly higher radiopacity (2.8 ± 0.3 mmAl) than other groups (p < 0,05). Cytotoxicity evaluation showed gingival cell viability higher than 80% for all groups. SIGNIFICANCE: Addition of up to 50%wt of barium glass in experimental 3D printing resin-based composites showed promising results for long-term restorative structures.

Asunto(s)

Compuestos de Bario , Resinas Compuestas , Ensayo de Materiales , Metacrilatos , Polietilenglicoles , Impresión Tridimensional , Resinas Compuestas/química , Compuestos de Bario/química , Polietilenglicoles/química , Metacrilatos/química , Poliuretanos/química , Resistencia Flexional , Vidrio/química , Ácidos Polimetacrílicos/química , Bisfenol A Glicidil Metacrilato/química , Humanos , Fibroblastos/efectos de los fármacos , Encía , Fotoiniciadores Dentales/química , Polimerizacion , Propiedades de Superficie , Dióxido de Silicio

RESUMEN

OBJECTIVE: To investigate the effect of hydrophilic/permeable polymer matrices on water sorption/solubility (WS/SL), Ca2+ release, mechanical properties and hydrolytic degradation of composites containing dicalcium phosphate dihydrate (DCPD) particles. METHODS: Six composites were tested, all with 10 vol% of glass particles and either 30 vol% or 40 vol% DCPD. Composites containing 1BisGMA:1TEGDMA in mols (at both inorganic levels) were considered controls. Four materials were formulated where 0.25 or 0.5 of the BisGMA/TEGDMA was replaced by pyromellitic dianhydride glycerol dimethacrylate (PMGDM)/ polyethylene glycol dimethacrylate (PEGDMA). Composites were tested for degree of conversion (FTIR spectroscopy), WS/SL (ISO 4049) and Ca2+ release (inductively coupled plasma optical emission spectroscopy). Fracture toughness (FT) and biaxial flexural strength/modulus (BFS/FM) were determined after 24 h and 60 days in water. The contributions of diffusional and relaxational mechanisms to Ca2+ release kinetics were analyzed using the semi-empirical Salim-Peppas model. Data were analysed by ANOVA/Tukey test (alpha: 0.05). RESULTS: WS/SL was higher for composites containing PMGDM/PEGDMA compared to the controls (p < 0.001). Only at 40% DCPD the 0.5 PMGDM/PEGDMA composite showed statistically higher Ca2+ release than the control. Relaxation diffusion was the main release mechanism. Initial FT was not negatively affected by matrix composition. BFS (both DCPD fractions) and FM (30% DCPD) were lower for composites with hydrophilic/permeable networks (p < 0.01). After 60 days in water, composites with PMGDM/PEGDMA presented significant reductions in FT, while all composites had reductions in BFS/FM. SIGNIFICANCE: Increasing matrix hydrophilicity/permeability significantly increased Ca2+ release only at a high DCPD fraction.

Asunto(s)

Fosfatos de Calcio , Resinas Compuestas , Resistencia Flexional , Interacciones Hidrofóbicas e Hidrofílicas , Ensayo de Materiales , Metacrilatos , Polietilenglicoles , Ácidos Polimetacrílicos , Resinas Compuestas/química , Polietilenglicoles/química , Metacrilatos/química , Fosfatos de Calcio/química , Ácidos Polimetacrílicos/química , Calcio/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Bisfenol A Glicidil Metacrilato/química , Agua/química , Módulo de Elasticidad , Benzoatos

RESUMEN

This study evaluated a new method of adhesive system application on the bond strength between fiber post and root dentin using two adhesive systems. The canals of sixty bovine incisors were prepared and obturated. The roots were divided into six groups (n=10) according to the adhesive system (Clearfil SE - CSE and Single Bond Universal - SBU) and the application strategy (microbrush - MB; rotary brush - RB; and ultrasonic tip - US). The glass fiber posts were cemented with resin cement (RelyX ARC). The roots were sectioned perpendicularly to their long axis, and three slices per root were obtained. Previously to the push-out test, confocal laser scanning microscopy (CLSM) was performed to illustrate the interfacial adaptation of the cement to the root canal walls. Failure patterns were analyzed with 40x magnification. Shapiro-Wilk indicated a normal distribution of the data. The bond strength values were compared using one-way ANOVA and Tukey's tests. Student's T test analyzed the differences between the adhesive systems within each third and protocol. A significance level of 5% was used. CSE with RB showed higher mean bond strength values compared to MB (conventional technique) (P < 0.05). US application resulted in intermediate bond strength values for CSE (P > 0.05). The application of SBU using RB generated higher mean bond strength values compared to MB and US (P < 0.05). Adhesive failures were predominant (65.5%). CSE and SBU application with the new rotary brush improved the bond strength of fiber posts to root dentin compared to the conventional strategy.

Asunto(s)

Dentina , Técnica de Perno Muñón , Cementos de Resina , Bovinos , Animales , Cementos de Resina/química , Recubrimiento Dental Adhesivo/métodos , Bisfenol A Glicidil Metacrilato/química , Recubrimientos Dentinarios/química , Microscopía Confocal , Ácidos Polimetacrílicos/química , Ensayo de Materiales , Vidrio/química , Raíz del Diente , Polietilenglicoles/química , Análisis del Estrés Dental

RESUMEN

OBJECTIVE: To evaluate the in vitro and in vivo toxicities of polyethylene glycol-coated gold nanoparticles synthesized using a one-step process. METHODS: Gold nanoparticles were prepared via a co-precipitation method using polyethylene glycol, and the synthesis product was characterized. For the in vitro evaluation, a flow cytometry analysis with Annexin V and iodide propidium staining was used to assess cytotoxicity in MG-63 cells labeled with 10, 50, and 100µg/mL of nanoparticle concentration. For the in vivo evaluation, nanoparticles were administered intraperitoneally at a dose of 10mg/kg dose in 10-week-old mice. Toxicity was assessed 24 hours and 7 days after administration via histopathological analysis of various tissues, as well as through renal, hepatic, and hematopoietic evaluations. RESULTS: Synthesized nanoparticles exhibited different hydrodynamic sizes depending on the medium: 51.27±1.62nm in water and 268.12±28.45nm (0 hour) in culture medium. They demonstrated a maximum absorbance at 520nm and a zeta potential of -8.419mV. Cellular viability exceeded 90%, with less than 3% early apoptosis, 6% late apoptosis, and 1% necrosis across all labeling conditions, indicating minimal cytotoxicity differences. Histopathological analysis highlighted the accumulation of nanoparticles in the mesentery; however, no lesions or visible agglomeration was observed in the remaining tissues. Renal, hepatic, and hematopoietic analyses showed no significant differences at any time point. CONCLUSION: Polyethylene glycol-coated gold nanoparticles exhibit extremely low toxicity and high biocompatibility, showing promise for future studies.

Asunto(s)

Oro , Nanopartículas del Metal , Polietilenglicoles , Polietilenglicoles/toxicidad , Polietilenglicoles/química , Oro/toxicidad , Oro/química , Animales , Nanopartículas del Metal/toxicidad , Ratones , Supervivencia Celular/efectos de los fármacos , Citometría de Flujo , Apoptosis/efectos de los fármacos , Humanos , Tamaño de la Partícula , Masculino , Riñón/efectos de los fármacos , Riñón/patología , Factores de Tiempo

RESUMEN

Nanotechnology has emerged as a promising avenue for enhancing the efficacy of vaccine delivery systems. This study investigates the utilization of nanogels as carriers for the model antigen ovalbumin, with a focus on in vivo assessments in equine and murine models. Nanogels, owing to their biocompatibility and tunable physicochemical properties, offer a versatile platform for efficient antigen encapsulation and controlled release. The encapsulation efficiency and physicochemical characteristics of ovalbumin-loaded nanogels were comprehensively characterized. In vitro biocompatibility was evaluated, finding excellent properties of these nanogels. In vivo evaluations were conducted on both equine and murine subjects, assessing immunogenicity through antibody and splenic cell response. Furthermore, the study propose the potential use of nanogels in tailoring immune responses through the modulation of antigen release kinetics. The results obtained in the in vitro assays showed an increase in the uptake of nanogels by APCs compared to free antigen (OVA). In mice, an absence of inflammatory response in the inoculation site was observed, without systemic damage in the evaluated organs. In addition, non-significant humoral response was found nor cellular proliferation and proinflammatory cytokine production, compared with a traditional adjuvant as aluminum hydroxide, in both animal models. These findings allow further insights into nanogel-based delivery systems and offer valuable insights into their application in various animal models. In conclusion, this research establishes the utility of nanogels as effective carriers for antigens-based vaccines, with interesting biocompatibility properties and highly taken affinity by antigen-presenting cells, without inducing inflammation at the injection site. The study underscores the potential of nanogel technology in revolutionizing vaccine design and highlights the importance of tailored approaches for diverse target species.

Asunto(s)

Ovalbúmina , Animales , Ratones , Ovalbúmina/inmunología , Ovalbúmina/administración & dosificación , Caballos/inmunología , Nanogeles/química , Vacunas/inmunología , Vacunas/administración & dosificación , Femenino , Portadores de Fármacos/química , Antígenos/inmunología , Antígenos/administración & dosificación , Ratones Endogámicos BALB C , Materiales Biocompatibles/química , Adyuvantes Inmunológicos/administración & dosificación , Citocinas/metabolismo , Polietilenglicoles/química , Sistemas de Liberación de Medicamentos , Polietileneimina/química

RESUMEN

OBJECTIVE: Stress distribution assessment by finite elements analysis in poly(etheretherketone) (PEEK) implant and abutment as retainers of single crowns in the anterior region. MATERIALS AND METHODS: Five 3D models were created, varying implant/abutment manufacturing materials: titanium (Ti), zirconia (Zr), pure PEEK (PEEKp), carbon fiber-reinforced PEEK (PEEKc), glass fiber-reinforced PEEK (PEEKg). A 50 N load was applied 30o off-axis at the incisal edge of the upper central incisor. The Von Mises stress (σvM) was evaluated on abutment, implant/screw, and minimum principal stress (σmin) and maximum shear stress (τmax) for cortical and cancellous bone. RESULTS: The abutment σvM lowest stress was observed in PEEKp group, being 70% lower than Ti and 74% than Zr. On the implant, PEEKp reduced 68% compared to Ti and a 71% to Zr. In the abutment screws, an increase of at least 33% was found in PEEKc compared to Ti, and of at least 81% to Zr. For cortical bone, the highest τmax values were in the PEEKp group, and a slight increase in stress was observed compared to all PEEK groups with Ti and Zr. For σmin, the highest stress was found in the PEEKc. Stress increased at least 7% in cancellous bone for all PEEK groups. CONCLUSION: Abutments and implants made by PEEKc concentrate less σvM stress, transmitting greater stress to the cortical and medullary bone. CLINICAL RELEVANCE: The best stress distribution in PEEKc components may contribute to decreased stress shielding; in vitro and in vivo research is recommended to investigate this.

Asunto(s)

Benzofenonas , Coronas , Pilares Dentales , Análisis del Estrés Dental , Análisis de Elementos Finitos , Cetonas , Ensayo de Materiales , Polietilenglicoles , Polímeros , Titanio , Circonio , Cetonas/química , Polietilenglicoles/química , Humanos , Circonio/química , Titanio/química , Fibra de Carbono/química , Diseño de Implante Dental-Pilar , Incisivo , Materiales Dentales/química , Implantes Dentales de Diente Único , Hueso Cortical , Vidrio/química , Diseño de Prótesis Dental