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1.
Sci Rep ; 14(1): 10798, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734777

RESUMO

The nucleation of carbonate-containing apatite on the biomaterials surface is regarded as a significant stage in bone healing process. In this regard, composites contained hydroxyapatite (Ca10(PO4)6(OH)2, HA), wollastonite (CaSiO3, WS) and polyethersulfone (PES) were synthesized via a simple solvent casting technique. The in-vitro bioactivity of the prepared composite films with different weight ratios of HA and WS was studied by placing the samples in the simulated body fluid (SBF) for 21 days. The results indicated that the the surface of composites containing 2 wt% HA and 4 wt% WS was completely covered by a thick bone-like apatite layer, which was characterized by Grazing incidence X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectrometer, field emission electron microscopy and energy dispersive X-ray analyzer (EDX). The degradation study of the samples showed that the concentration of inorganic particles could not influence the degradability of the polymeric matrix, where all samples expressed similar dexamethasone (DEX) release behavior. Moreover, the in-vitro cytotoxicity results indicated the significant cyto-compatibility of all specimens. Therefore, these findings revealed that the prepared composite films composed of PES, HA, WS and DEX could be regarded as promising bioactive candidates with low degradation rate for bone tissue engineering applications.


Assuntos
Materiais Biocompatíveis , Substitutos Ósseos , Durapatita , Nanocompostos , Silicatos , Durapatita/química , Nanocompostos/química , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Silicatos/química , Materiais Biocompatíveis/química , Compostos de Cálcio/química , Liberação Controlada de Fármacos , Dexametasona/química , Dexametasona/farmacologia , Polímeros/química , Humanos , Difração de Raios X , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Animais
2.
PeerJ ; 12: e17237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699192

RESUMO

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Indóis , Óxidos , Polímeros , Materiais Restauradores do Canal Radicular , Silicatos , Propriedades de Superfície , Polímeros/química , Indóis/química , Silicatos/química , Compostos de Cálcio/química , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Compostos de Alumínio/química , Humanos , Combinação de Medicamentos , Microscopia Eletrônica de Varredura , Microscopia de Força Atômica/métodos , Microscopia Confocal , Teste de Materiais , Raiz Dentária/lesões , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia
3.
Biosens Bioelectron ; 258: 116343, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38718636

RESUMO

Recently, the non-covalently activated supramolecular scaffold method has become a prominent research area in the field of intelligent materials. Here, the inorganic clay (LP) promoted the AIE properties of 4,4',4″,4‴-(ethene-1,1,2,2-tetrayltetrakis(benzene-4,1-diyl))tetrakis(1-ethylpyridin-1-ium) (P-TPE), showing an astonishing 42-fold enhancement of the emission intensity of the yellow-green luminescence and a 34-fold increase of the quantum yield via organic-inorganic supramolecular strategy as well as the efficient light-harvesting properties (energy transfer efficiency up to 33 %) after doping with the dye receptor Rhodamine B. Furthermore, the full-color spectral regulation, including white light, was achieved by adjusting the ratio of the donor to the acceptor component and co-assembling with the carbon dots (CD). Interestingly, this TPE-based non-covalently activated full-color supramolecular light-harvesting system (LHS) could be achieved not only in aqueous media but also in the hydrogel and the solid state. More importantly, this panchromatic tunable supramolecular LHS exhibited the multi-mode and quadruple digital logic encryption property as well as the specific detection ability towards the perfluorobutyric acid and the perfluorobutanesulfonic acid, which are harmful to human health in drinking water. This result develops a simple, convenient and effective approach for the intelligent anti-counterfeiting and the pollutant sensing.


Assuntos
Técnicas Biossensoriais , Poluentes Químicos da Água , Técnicas Biossensoriais/métodos , Poluentes Químicos da Água/análise , Corantes Fluorescentes/química , Fluorocarbonos/química , Luminescência , Silicatos/química , Rodaminas/química , Limite de Detecção , Pontos Quânticos/química
4.
Braz Oral Res ; 38: e028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597547

RESUMO

Acidic pH can modify the properties of repair cements. In this study, volumetric change and solubility of the ready-to-use bioceramic repair cement Bio-C Repair (BCR, Angelus, Londrina, PR, Brazil) were evaluated after immersion in phosphate-buffered saline (PBS) (pH 7.0) or butyric acid (pH 4.5). Solubility was determined by the difference in initial and final mass using polyethylene tubes measuring 4 mm high and 6.70 mm in internal diameter that were filled with BCR and immersed in 7.5 mL of PBS or butyric acid for 7 days. The volumetric change was established by using bovine dentin tubes measuring 4 mm long with an internal diameter of 1.5 mm. The dentin tubes were filled with BCR at 37°C for 24 hours. Scanning was performed with micro-computed tomography (micro-CT; SkyScan 1176, Bruker, Kontich, Belgium) with a voxel size of 8.74 µm. Then, the specimens were immersed in 1.5 mL of PBS or butyric acid at and 37 °C for 7 days. After this period, a new micro-CT scan was performed. Bio-C Repair showed greater mass loss after immersion in butyric acid when compared with immersion in PBS (p<0.05). Bio-C Repair showed volumetric loss after immersion in butyric acid and increase in volume after immersion in PBS (p<0.05). The acidic pH influenced the solubility and dimensional stability of the Bio-C Repair bioceramic cement, promoting a higher percentage of solubility and decrease in volumetric values.


Assuntos
Óxidos , Materiais Restauradores do Canal Radicular , Animais , Bovinos , Solubilidade , Óxidos/química , Compostos de Cálcio/química , Microtomografia por Raio-X , Ácido Butírico , Teste de Materiais , Cimentos Dentários/química , Cimentos de Ionômeros de Vidro , Concentração de Íons de Hidrogênio , Silicatos/química , Materiais Restauradores do Canal Radicular/química
5.
J Hazard Mater ; 470: 134190, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593659

RESUMO

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.


Assuntos
Descontaminação , Paraoxon , Pele , Descontaminação/métodos , Animais , Pele/efeitos dos fármacos , Humanos , Suínos , Paraoxon/toxicidade , Paraoxon/química , Compostos de Alumínio/química , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química , Álcool de Polivinil/química , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Tensoativos/química , Fibroblastos/efeitos dos fármacos
6.
Int J Biol Macromol ; 266(Pt 2): 131337, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574911

RESUMO

Utilization of injectable hydrogels stands as a paradigm of minimally invasive intervention in the context of intervertebral disc degeneration treatment. Restoration of nucleus pulposus (NP) function exerts a profound influence in alleviating back pain. This study introduces an innovative class of injectable shear-thinning hydrogels, founded on quaternized chitosan (QCS), gelatin (GEL), and laponite (LAP) with the capacity for sustained release of the anti-inflammatory drug, celecoxib (CLX). First, synthesis of Magnesium-Aluminum-Layered double hydroxide (LDH) was achieved through a co-precipitation methodology, as a carrier for celecoxib and a source of Mg ions. Intercalation of celecoxib within LDH layers (LDH-CLX) was verified through a battery of analytical techniques, including FTIR, XRD, SEM, EDAX, TGA and UV-visible spectroscopy confirmed a drug loading efficiency of 39.22 ± 0.09 % within LDH. Then, LDH-CLX was loaded in the optimal GEL-QCS-LAP hydrogel under physiological conditions. Release behavior (15 days profile), mechanical properties, swelling ratio, and degradation rate of the resulting composite were evaluated. A G* of 15-47 kPa was recorded for the hydrogel at 22-40 °C, indicating gel stability in this temperature range. Self-healing properties and injectability of the composite were proved by rheological measurements. Also, ex vivo injection into intervertebral disc of sheep, evidenced in situ forming and NP cavity filling behavior of the hydrogel. Support of GEL-QCS-LAP/LDH-CLX (containing mg2+ ions) for viability and proliferation (from ~94 % on day 1 to ~134 % on day 7) of NP cells proved using MTT assay, DAPI and Live/Dead assays. The hydrogel could significantly upregulate secretion of glycosaminoglycan (GAG, from 4.68 ± 0.1 to 27.54 ± 1.0 µg/ml), when LHD-CLX3% was loaded. We conclude that presence of mg2+ ion and celecoxib in the hydrogel can lead to creation of a suitable environment that encourages GAG secretion. In conclusion, the formulated hydrogel holds promise as a minimally invasive candidate for degenerative disc repair.


Assuntos
Celecoxib , Quitosana , Gelatina , Hidrogéis , Silicatos , Hidrogéis/química , Hidrogéis/farmacologia , Celecoxib/farmacologia , Celecoxib/química , Celecoxib/administração & dosagem , Quitosana/química , Gelatina/química , Silicatos/química , Silicatos/farmacologia , Núcleo Pulposo/efeitos dos fármacos , Núcleo Pulposo/metabolismo , Animais , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Injeções , Reologia
7.
Bioresour Technol ; 400: 130694, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614149

RESUMO

Recycling waste into commercial products is a profitable strategy but the lifetime of immobilized cells for long-term waste treatment remains a problem. This study presents alternative cell immobilization methods for valorizing food waste (FW) and oily food waste (OFW) to microbial carotenoids and proteins. Carriers (pumice or smectite), magnetite nanoparticles, and isolated photosynthetic bacteria were integrated to obtain magnetically recoverable bacteria-pumice and bacteria-smectite nanocomposites. After recycling five batches (50 d), chemical oxygen demand removal from FW reached 76% and 78% with the bacteria-pumice and bacteria-smectite nanocomposite treatments, respectively, and oil degradation in OFW reached 71% and 62%, respectively. Destructive changes did not occur, suggesting the durability of nanocomposites. The used nanocomposites had no impact on the lifespan of Moina macrocopa or water quality as assessed by toxicity analysis. Bacteria-pumice and bacteria-smectite nanocomposites are efficient for food waste recycling and do not require secondary treatment before being discharged into the environment.


Assuntos
Bactérias , Células Imobilizadas , Nanocompostos , Silicatos , Zooplâncton , Nanocompostos/química , Silicatos/química , Silicatos/farmacologia , Animais , Células Imobilizadas/metabolismo , Alimentos , Reciclagem , Análise da Demanda Biológica de Oxigênio , Resíduos , Biodegradação Ambiental , Óleos/química , Perda e Desperdício de Alimentos
8.
Nanotechnology ; 35(31)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38663370

RESUMO

The overuse of antibiotics currently results in the presence of various antibiotics being detected in water bodies, which poses potential risks to human health and the environment. Therefore, it is highly significant to remove antibiotics from water. In this study, we developed novel rod-like NiCo-phyllosilicate hybrid catalysts on calcined natural zeolite (NiCo@C-zeolite) via a facile one-pot process. The presence of the zeolite served as both a silicon source and a support, maintaining a high specific surface area of the NiCo@C-zeolite. Remarkably, NiCo@C-zeolite exhibited outstanding catalytic performance in antibiotic degradation under PMS activation. Within just 5 min, the degradation rate of metronidazole (MNZ) reached 96.14%, ultimately achieving a final degradation rate of 99.28%. Furthermore, we investigated the influence of catalyst dosage, PMS dosage, MNZ concentration, initial pH value, and various inorganic anions on the degradation efficiency of MNZ. The results demonstrated that NiCo@C-zeolite displayed outstanding efficacy in degrading MNZ under diverse conditions and maintained a degradation rate of 94.86% at 60 min after three consecutive cycles of degradation. Free radical quenching experiments revealed that SO•-4played a significant role in the presence of NiCo@C-zeolite-PMS system. These findings indicate that the novel rod-like NiCo-phyllosilicate hybrid catalysts had excellent performance in antibiotic degradation.


Assuntos
Antibacterianos , Zeolitas , Zeolitas/química , Antibacterianos/química , Antibacterianos/síntese química , Catálise , Poluentes Químicos da Água/química , Metronidazol/química , Purificação da Água/métodos , Silicatos/química
9.
Waste Manag ; 182: 225-236, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677140

RESUMO

This article explores the impact of thermally treated asbestos-cement waste (ACWT) on metakaolin-based geopolymers, using liquid sodium silicate (LSS) and liquid potassium silicate (LKS) as alkali activators. Through statistical mixture design, various formulations were tested for rheological parameters, mineralogical composition, efflorescence mass, electrical conductivity, compressive strength, and CO2 emissions. Formulations with sodium silicate exhibited higher yield stress compared to those with potassium silicate, while flash setting occurred in LKS-activated mixtures with high ACWT content. Alkali activator content significantly affected mechanical strength and leachate electrical conductivity. CO2 emissions were higher for LKS-activated formulations but lower for those with more ACWT. Finally, by incorporating ACWT, it was possible to optimize the formulations, resulting in high compressive strength, reduced free ions, and reduced negative environmental impact.


Assuntos
Amianto , Dióxido de Carbono , Materiais de Construção , Silicatos , Dióxido de Carbono/análise , Silicatos/química , Materiais de Construção/análise , Amianto/análise , Força Compressiva , Resíduos Industriais/análise , Condutividade Elétrica , Temperatura Alta
10.
Int J Biol Macromol ; 267(Pt 1): 131580, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38688788

RESUMO

Despite the clinical success of tricalcium silicate (TCS)-based materials in endodontics, the inferior handling characteristic, poor anti-washout property and slow setting kinetics hindered their wider applications. To solve these problems, an injectable fast-setting TCS/ß-tricalcium phosphate/monocalcium phosphate anhydrous (ß-TCP/MCPA) cement was developed for the first time by incorporation of hydroxypropyl methylcellulose (HPMC) and ß-TCP/MCPA. The physical-chemical characterization (setting time, anti-washout property, injectability, compressive strength, apatite mineralization and sealing property) of TCS/(ß-TCP/MCPA) were conducted. Its hydration mechanism was also investigated. Furthermore, the cytocompatibility and osteogenic/odontogenic differentiation of stem cells isolated from human exfoliated deciduous teeth (SHED) treated with TCS/ß-TCP/MCPA were studied. The results showed that HPMC could provide TCS with good anti-washout ability and injectability but slow hydration process. However, ß-TCP/MCPA effectively enhanced anti-washout characteristics and reduced setting time due to faster hydration kinetics. TCS/(ß-TCP/MCPA) obtained around 90 % of injection rate and high compressive strength whereas excessive additions of ß-TCP/MCPA compromised its injectability and compressive strength. TCS/(ß-TCP/MCPA) can induce apatite deposition and form a tight marginal sealing at the dentin-cement interface. Additionally, TCS/(ß-TCP/MCPA) showed good biocompatibility and promoted osteo/odontogenic differentiation of SHED. In general, our results indicated that TCS/(ß-TCP/MCPA) may be particularly promising as an injectable bioactive cements for endodontic treatment.


Assuntos
Compostos de Cálcio , Fosfatos de Cálcio , Derivados da Hipromelose , Silicatos , Silicatos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Compostos de Cálcio/química , Humanos , Derivados da Hipromelose/química , Osteogênese/efeitos dos fármacos , Teste de Materiais , Diferenciação Celular/efeitos dos fármacos , Força Compressiva , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia
11.
Dent Mater ; 40(5): 842-857, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38580561

RESUMO

OBJECTIVES: Lithium silicate-based glass ceramics have evolved as a paramount restorative material in restorative and prosthetic dentistry, exhibiting outstanding esthetic and mechanical performance. Along with subtractive machining techniques, this material class has conquered the market and satisfied the patients' needs for a long-lasting, excellent, and metal-free alternative for single tooth replacements and even smaller bridgework. Despite the popularity, not much is known about the material chemistry, microstructure and terminal behaviour. METHODS: This article combines a set of own experimental data with extensive review of data from literature and other resources. Starting at manufacturer claims on unique selling propositions, properties, and microstructural features, the aim is to validate those claims, based on glass science. Deep knowledge is mandatory for understanding the microstructure evolution during the glass ceramic process. RESULTS: Fundamental glass characteristics have been addressed, leading to formation of time-temperature-transformation (TTT) diagrams, which are the basis for kinetic description of the glass ceramic process. Nucleation and crystallization kinetics are outlined in this contribution as well as analytical methods to describe the crystalline fraction and composition qualitatively and quantitatively. In relation to microstructure, the mechanical performance of lithium silicate-based glass ceramics has been investigated with focus on fracture strength versus fracture toughness as relevant clinical predictors. CONCLUSION: Fracture toughness has been found to be a stronger link to initially outlined manufacturer claims, and to more precisely match ISO recommendations for clinical indications.


Assuntos
Cerâmica , Teste de Materiais , Silicatos , Cerâmica/química , Silicatos/química , Vidro/química , Propriedades de Superfície , Materiais Dentários/química , Cristalização , Compostos de Lítio/química , Porcelana Dentária/química
12.
Carbohydr Polym ; 336: 122128, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670759

RESUMO

Traditional submucosal filling materials frequently show insufficient lifting height and duration during clinical procedures. Here, the anionic polysaccharide polymer sodium carboxymethyl starch and cationic Laponite to prepare a hydrogel with excellent shear-thinning ability through physical cross-linking, so that it can achieve continuous improvement of the mucosal cushion through endoscopic injection. The results showed that the hydrogel (56.54 kPa) had a lower injection pressure compared to MucoUp (68.56 kPa). The height of submucosal lifting height produced by hydrogel was higher than MucoUp, and the height maintenance ability after 2 h was 3.20 times that of MucoUp. At the same time, the hydrogel also showed satisfactory degradability and biosafety, completely degrading within 200 h. The hemolysis rate is as low as 0.76 %, and the cell survival rate > 80 %. Subcutaneous implantation experiments confirmed that the hydrogel showed no obvious systemic toxicity. Animal experiments clearly demonstrated the in vivo feasibility of using hydrogels for submucosal uplift. Furthermore, successful endoscopic submucosal dissection was executed on a live pig stomach, affirming the capacity of hydrogel to safely and effectively facilitate submucosal dissection and mitigate adverse events, such as bleeding. These results indicate that shear-thinning hydrogels have a wide range applications as submucosal injection materials.


Assuntos
Hidrogéis , Amido , Amido/análogos & derivados , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Amido/química , Suínos , Camundongos , Mucosa Gástrica/metabolismo , Ressecção Endoscópica de Mucosa/métodos , Injeções , Humanos , Hemólise/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química
13.
J Dent ; 144: 104952, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508442

RESUMO

OBJECTIVES: Evaluation of the two-body wear of lithium-silicate ceramics against different antagonists compared to a direct resin composite and human teeth. METHODS: Initial LiSi Block [LISI], IPS e.max CAD [EMA], and CEREC Tessera [TESE] were investigated and compared with direct resin composite [FILL] and human teeth [tooth]. As antagonists were used: steatite, ceramic, and human enamel. The control group tooth was only tested with enamel antagonist. The combinations underwent thermomechanical aging using a chewing simulator. Material losses were calculated using GOM-analysis software. Kolmogorov-Smirnov test, Kruskal-Wallis H, Mann-Whitney-U-test with Bonferroni correction and Spearman-rho correlation were calculated. A fractographic analysis was performed. RESULTS: Within TESE, enamel antagonists led to lower restoration losses than steatite and ceramic antagonists. Within FILL, enamel and steatite antagonists caused lower material losses compared to ceramic antagonists. Against steatite antagonists, LISI showed lowest material losses. Against ceramic antagonists, the use of LISI led to lower material losses compared to FILL. Against tooth antagonists, TESE showed lower material losses than tooth and FILL and LISI lower than FILL. Within LISI, steatite antagonists showed lower material losses on the antagonist than ceramic. Within EMA, steatite antagonists showed higher material losses than ceramic ones. Within ceramic antagonists, LISI restoration material showed lower material losses than FILL and EMA. CONCLUSIONS: Regardless of the antagonist material, the material losses of LISI and EMA were comparable. However, the abrasion resistance of LISI tended to be higher than EMA. CLINICAL SIGNIFICANCE: LISI is a fully crystallized lithium-silicate ceramic and no longer needs to be processed after milling. In addition, the abrasion resistance is very good, regardless of the antagonist material chosen.


Assuntos
Cerâmica , Resinas Compostas , Esmalte Dentário , Porcelana Dentária , Óxido de Magnésio , Teste de Materiais , Dióxido de Silício , Humanos , Resinas Compostas/química , Porcelana Dentária/química , Esmalte Dentário/efeitos dos fármacos , Cerâmica/química , Materiais Dentários/química , Silicatos/química , Propriedades de Superfície , Desgaste de Restauração Dentária , Desenho Assistido por Computador , Lítio
14.
Dent Mater J ; 43(2): 276-285, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38447980

RESUMO

Premixed calcium silicate cements (pCSCs) contain vehicles which endow fluidity and viscosity to CSCs. This study aimed to investigate the effects of three vehicles, namely, polyethylene glycol (PEG), propylene glycol (PG), and dimethyl sulfoxide (DMSO), on the physicochemical properties and biocompatibility of pCSCs. The setting time, solubility, expansion rate, and mechanical strength of the pCSCs were evaluated, and the formation of calcium phosphate precipitates was assessed in phosphate-buffered saline (PBS). The effects of pCSC extracts on the osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. Finally, the tissue compatibility of pCSCs in rat femurs was observed. CSC containing PEG (CSC-PEG) exhibited higher solubility and setting time, and CSC-DMSO showed the highest expansion rate and mechanical strength. All pCSCs generated calcium phosphate precipitates. The extract of CSC-PG induced the highest expressions of osteogenic markers along with the greatest calcium deposites. When implanted in rat femurs, CSC-PEG was absorbed considerably, whereas CSC-PG remained relatively unaltered inside the femur.


Assuntos
Dimetil Sulfóxido , Osteogênese , Teste de Materiais , Compostos de Cálcio/farmacologia , Compostos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/química , Silicatos/farmacologia , Silicatos/química , Cálcio , Cimento de Silicato/química , Cimentos Dentários/farmacologia , Cimentos Dentários/química
15.
Sci Total Environ ; 925: 171762, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508270

RESUMO

Ores serve as energy and nutrient sources for microorganisms. Through complex biochemical processes, microorganisms disrupt the surface structure of ores and release metal elements. However, there is limited research on the mechanisms by which bacteria with different nutritional modes act during the leaching process of different crystal structure ores. This study evaluated the leaching efficiency of two types of bacteria with different nutritional modes, heterotrophic bacterium Bacillus mucilaginosus (BM) and autotrophic bacterium Acidithiobacillus ferrooxidans (AF), on different crystal structure lithium silicate ores (chain spodumene, layered lepidolite and ring elbaite). The aim was to understand the behavioral differences and decomposition mechanisms of bacteria with different nutritional modes in the process of breaking down distorted crystal lattices of ores. The results revealed that heterotrophic bacterium BM primarily relied on passive processes such as bacterial adsorption, organic acid corrosion, and the complexation of small organic acids and large molecular polymers with metal ions. Autotrophic bacterium AF, in addition to exhibiting stronger passive processes such as organic acid corrosion and complexation, also utilized an active transfer process on the cell surface to oxidize Fe2+ in the ores for energy maintenance and intensified the destruction of ore lattices. As a result, strain AF exhibited a greater leaching effect on the ores compared to strain BM. Regarding the three crystal structure ores, their different stacking modes and proportions of elements led to significant differences in structural stability, with the leaching effect being highest for layered structure, followed by chain structure, and then ring structure. These findings indicate that bacteria with different nutritional modes exhibit distinct physiological behaviors related to their nutritional and energy requirements, ultimately resulting in different sequences and mechanisms of metal ion release from ores after lattice damage.


Assuntos
Acidithiobacillus , Bactérias , Lítio , Bactérias/metabolismo , Metais/metabolismo , Silicatos/química , Íons
16.
J Clin Pediatr Dent ; 48(2): 93-101, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38548638

RESUMO

When dental pulp is exposed, it must be covered with a biocompatible material to form reparative dentine. The material used, besides being biocompatible, should have an ideal surface structure for the attachment, proliferation and differentiation of dental pulp stem cells. This study aimed to evaluate the porosity of the microstructures of four pulp capping materials using micro-computed tomography (micro-CT). Biodentine, Bioaggregate, TheraCal and Dycal materials were prepared according to the manufacturer's instructions using 2 × 9 mm Teflon molds. A total of 60 samples, 15 in each group, were scanned using micro-CT. Open and closed pores and the total porosity of the microstructures of the materials were assessed. The findings obtained from the study were analyzed via the Kruskal-Wallis test followed by the Mann-Whitney U test. The porosity of Bioaggregate was significantly higher than that of Biodentine, Dycal and TheraCal in all porosity values. While Biodentine did not show a statistically significant difference in open and total porosity values from either TheraCal or Dycal, closed porosity values of Dycal were significantly higher than those of Biodentine and TheraCal. Because of the affinity of cells to porous surfaces, the pulp capping materials' microstructure may affect the pulp capping treatment's success. From this perspective, the use of Bioaggregate in direct pulp capping may increase the success of treatment.


Assuntos
Hidróxido de Cálcio , Capeamento da Polpa Dentária , Hidroxiapatitas , Minerais , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Humanos , Capeamento da Polpa Dentária/métodos , Microtomografia por Raio-X , Porosidade , Óxidos/química , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico , Silicatos/química , Compostos de Cálcio/química , Combinação de Medicamentos , Compostos de Alumínio/química
17.
Luminescence ; 39(3): e4698, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462505

RESUMO

In this study, cerium ion (Ce3+ )-doped calcium scandium silicate garnet (Ca3 Sc2 Si3 O12 , abbreviated CSSG) phosphors were successfully synthesized using the sol-gel method. The crystal phase, morphology, and photoluminescence properties of the synthesized phosphors were thoroughly investigated. Under excitation by a blue light-emitting diode (LED) chip (450 nm), the CSSG phosphor displayed a wide emission spectrum spanning from green to yellow. Remarkably, the material exhibited exceptional thermal stability, with an emissivity ratio at 150°C to that at 25°C reaching approximately 85%. Additionally, the material showcased impressive optical performance when tested with a blue LED chip, including a color rendering index (CRI) exceeding 90, an R9 value surpassing 50, and a biological impact ratio (M/P) above 0.6. These noteworthy findings underscore the potential applications of CSSG as a white light-converting phosphor, particularly in the realm of human-centered lighting.


Assuntos
Cério , Iluminação , Humanos , Luz , Silicatos/química , Cálcio , Cério/química
18.
BMC Oral Health ; 24(1): 352, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504287

RESUMO

BACKGROUND: AH Plus, an epoxy resin-based sealer, is widely used in endodontic practice, owing to its good physical properties that confers longstanding dimensional stability and good adhesion to dentin. Nevertheless, its propensity to trigger inflammation, especially in its freshly mixed state, has been extensively documented. Phytochemicals such as Petasin, Pachymic acid, Curcumin, and Shilajit are known for their anti-inflammatory and analgesic effects. This study aimed to analyze and determine the effect of these natural products on the physical properties of AH Plus sealer when incorporated with the sealer. METHODS: AH Plus (AHR) sealer was mixed with 10% petasin, 0.75% pachymic, 0.5% and 6%shilajit to obtain AHP, AHA, AHC and AHS in the ratio of 10:1 and 5:1 respectively. Five samples of each material were assessed for setting time, solubility, flow, and dimensional stability in accordance with the ISO 6876:2012 standardization. Sealers were characterized through scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Statistical evaluation involved the Kolmogorov-Smirnov and Shapiro-Wilks tests for normality and the one-way ANOVA test for analysis. RESULTS: In this investigation, the characterisation analysis revealed a relatively similar microstructure in all the experimental root canal sealers. All experimental groups, excluding the control group, exhibited an increase in flow ranging from 11.9 to 31.4% at a 10:1 ratio. Similarly, for the 5:1 ratio, the increase ranged from 12.02 to 31.83%. In terms of dimensional stability, all groups at the 10:1 ratio showed a decrease compared to the control group. The addition of natural agents to AHR in 10:1 ratio led to a reduction in setting time by 8.9-31.6%, and at a 5:1 ratio, the reduction ranged from 8.1 to 31.5%. However, regarding solubility, the addition of natural agents did not induce any significant alterations. CONCLUSION: Based on the results of this study, it can be concluded that all tested root canal sealers exhibited properties that met the acceptable criteria outlined in the ISO 6876:2012 standardization.


Assuntos
Curcumina , Minerais , Resinas Vegetais , Materiais Restauradores do Canal Radicular , Sesquiterpenos , Triterpenos , Humanos , Materiais Restauradores do Canal Radicular/química , Curcumina/farmacologia , Resinas Epóxi , Teste de Materiais , Silicatos/química , Compostos de Cálcio/química
19.
J Mater Chem B ; 12(16): 3917-3926, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38536012

RESUMO

The repair capacity of skeletal muscle is severely diminished in massive skeletal muscle injuries accompanied by inflammation, resulting in muscle function loss and scar tissue formation. In the current work, we developed a tannic acid (TA)- and silicate ion-functionalized tissue adhesive poly(vinyl alcohol) (PVA)-starch composite hydrogel, referred to as PSTS (PVA-starch-TA-SiO32-). It was formed based on the hydrogen bonding of TA to organic polymers, as well as silicate-TA ligand interaction. PSTS could be gelatinized in minutes at room temperature with crosslinked network formation, making it applicable for injection. Further investigations revealed that PSTS had skeletal muscle-comparable conductivity and modulus to act as a temporary platform for muscle repairing. Moreover, PSTS could release TA and silicate ions in situ to inhibit bacterial growth, induce vascularization, and reduce oxidation, paving the way to the possibility of creating a favorable microenvironment for skeletal muscle regeneration and tissue fibrosis control. The in vivo model confirmed that PSTS could enhance muscle fiber regeneration and myotube formation, as well as reduce infection and inflammation risk. These findings thereby implied the great potential of PSTS in the treatment of formidable skeletal muscle injuries.


Assuntos
Hidrogéis , Músculo Esquelético , Polifenóis , Álcool de Polivinil , Silicatos , Amido , Taninos , Taninos/química , Taninos/farmacologia , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Músculo Esquelético/efeitos dos fármacos , Animais , Amido/química , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/síntese química , Silicatos/química , Silicatos/farmacologia , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
20.
Phys Med Biol ; 69(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529716

RESUMO

Objective. Lutetium yttrium oxyorthosilicate (LYSO) scintillation crystals are used in positron emission tomography (PET) due to their high gamma attenuation, fair energy resolution, and fast scintillation decay time. The enduring presence of the176Lu isotope, characterized by a half-life of 37.9 billion years, imparts a consistent radiation background (BG) profile that depends on the geometry and composition attributes of the LYSO crystals.Approach. In this work, we proposed a methodology for estimating the composition of LYSO crystals in cases where the exact Lutetium composition remains unknown. The connection between BG spectrum intensity and intrinsic radioactivity enables precise estimation of Lutetium density in LYSO crystal samples. This methodology was initially applied to a well-characterized LYSO crystal sample, yielding results closely aligned with the known composition. The composition estimation approach was extended to several samples of undisclosed LYSO crystals, encompassing single crystal and crystal array configurations. Furthermore, we model the background spectrum observed in the LYSO-based detector and validate the observed spectra via simulations.Main results. The estimated Lutetium composition exhibited adequate consistency across different samples of the same LYSO material, with variations of less than 1%. The result of the proposed approach coupled with the simulation successfully models the background radiation spectra in various LYSO-based detector geometries.Significance. The implications of this work extend to the predictive assessment of system behaviors and the autonomous configuration parameters governing LYSO-based detectors.


Assuntos
Lutécio , Ítrio , Lutécio/química , Tomografia por Emissão de Pósitrons/métodos , Silicatos/química
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