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1.
J Contemp Dent Pract ; 22(4): 357-360, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34267003

RESUMO

AIM AND OBJECTIVE: To determine and compare remineralizing efficacy of NovaMin, CPP-ACP, silver diamine fluoride (SDF), and P11-4. MATERIALS AND METHODS: Sixty permanent premolars were divided into four groups with 15 samples in each group; group I: self-assembling peptide (P11-4), group II: SDF, group III: Casein phosphopeptide-stabilized amorphous calcium phosphate (CPP-ACP), and group IV: NovaMin. Mineral content was assessed using a scanning electron microscope at 7, 14, and 21 days after remineralization with each agent. RESULTS: The mean remineralization in group I at 7 days was 1.73 ± 0.02, at 14 days was 1.79 ± 0.01, and at 21 days was 1.90±0.03. Mean remineralization in group II was 1.61 ± 0.01, 1.64 ± 0.02, and 1.73 ± 0.03 at 7, 14, and 21 days, respectively. Mean remineralization in group III was 1.62 ± 0.01, 1.65 ± 0.02, and 1.74 ± 0.05 at 7, 14, and 21 days, respectively. Mean remineralization in group IV was 1.59 ± 0.02, 1.62 ± 0.07, and 1.70 ± 0.09 at 7, 14, and 21 days, respectively. The maximum value was obtained on day 21. There was a significant difference in mean remineralization values between group I vs group II, group I vs group III, and group I vs group IV (p < 0.05). CONCLUSION: Self-assembling peptides showed maximum remineralization in tested specimens followed by CPP-ACP, SDF, and NovaMin-containing toothpaste. CLINICAL SIGNIFICANCE: CPP-ACP, SDF, and NovaMin-containing toothpaste can be indicated for remineralization of initial caries in clinical use.


Assuntos
Caseínas , Remineralização Dentária , Esmalte Dentário , Fluoretos Tópicos , Vidro , Compostos de Amônio Quaternário , Compostos de Prata
2.
Acta Cir Bras ; 36(6): e360603, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259788

RESUMO

PURPOSE: To evaluate the influence of bioactive glass and photobiomodulation therapy (PBMT) in calvarial bone repair process in rats submitted to zoledronic acid therapy. METHODS: Twenty-four rats were selected and treated with the dose of 0.035 mg/kg of zoledronic acid every two weeks, totalizing eight weeks, to induce osteonecrosis. After the drug therapy, surgical procedure was performed to create 5-mm diameter parietal bone defects in the calvarial region. The rats were then randomly assigned to groups according to the following treatments: AZC: control group, treated with blood clot; AZBIO: bone defect filled with bioactive glass; AZL: treated with blood clot and submitted to PBMT; and AZBIOL: treated with bioactive glass S53P4 and submitted to PBMT. Tissue samples were collected and submitted to histomorphometric analysis after 14 and 28 days. RESULTS: At 14 days, bone neoformation in the AZBIO (52.15 ± 9.77) and AZBIOL (49.77 ± 13.58) groups presented higher values (p ≤ 0.001) compared to the AZC (23.35 ± 10.15) and AZL groups (23.32 ± 8.75). At 28 days, AZBIO (80.24 ± 5.41)still presented significant higher bone recovery values when compared to AZC (59.59 ± 16.92)and AZL (45.25 ± 5.41) groups (p = 0.048). In the 28-day period, the AZBIOL group didn't show statistically significant difference with the other groups (71.79 ± 29.38). CONCLUSIONS: The bioactive glass is an effective protocol to stimulate bone neoformation in critical defects surgically created in rats with drug induced osteonecrosis, in the studied periods of 14 and 28 days.


Assuntos
Terapia com Luz de Baixa Intensidade , Animais , Regeneração Óssea , Vidro , Ratos , Ácido Zoledrônico
3.
J Contemp Dent Pract ; 22(3): 219-223, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210918

RESUMO

AIM AND OBJECTIVE: This study aims to evaluate the effect of different resin cements on the bond strength (BS) of custom-made glass fiber posts (GFPs) using the push-out test. MATERIALS AND METHODS: Twenty-four uniradicular bovine teeth were selected. The crowns were sectioned at the cementoenamel junction, and the root canals were treated. The post spaces of the teeth were prepared to a length of 12 mm to receive a GFP. The specimens were randomly assigned to three experimental groups (n = 8), according to the resin cement used to fix the GFPs: RelyX U200 (U200), Allcem Core (ACC), and Allcem Dual (ACD). Each specimen was sectioned into six slices per root third (cervical, middle, and apical), which were subjected to the push-out test. BS values were calculated and compared using the Kruskal-Wallis and Friedman tests. RESULTS: There were significant differences in the middle third, according to the resin cement type used (p < 0.05). ACD showed lower BS values (p < 0.05). Significant differences were observed for ACD among the thirds of the slices, with the lowest values also observed for the middle third (p < 0.05). CONCLUSION: The present study shows that ACC and U200 showed higher BS values compared with ACD, and were also less influenced by the depth of the root dentin. CLINICAL SIGNIFICANCE: The restoration of endodontically treated teeth is a challenge in dentistry, and, in most cases, will require installation of fiberglass pins. In this respect, several types of resin cements are indicated for cementation of these pins; for this reason, their adhesiveness must be adequately investigated. Conventional cements and self-adhesive cements have shown satisfactory performance in cementing the custom-made GFPs, thereby making these cements satisfactory clinical choices. The present study suggests that ACD had lower performance than the other two cements evaluated.


Assuntos
Colagem Dentária , Técnica para Retentor Intrarradicular , Animais , Bovinos , Cavidade Pulpar , Análise do Estresse Dentário , Dentina , Vidro , Teste de Materiais , Cimentos de Resina
4.
Nat Commun ; 12(1): 3365, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099717

RESUMO

Quantification of molecular interactions on a surface is typically achieved via label-free techniques such as surface plasmon resonance (SPR). The sensitivity of SPR originates from the characteristic that the SPR angle is sensitive to the surface refractive index change. Analogously, in another interfacial optical phenomenon, total internal reflection, the critical angle is also refractive index dependent. Therefore, surface refractive index change can also be quantified by measuring the reflectivity near the critical angle. Based on this concept, we develop a method called critical angle reflection (CAR) imaging to quantify molecular interactions on glass surface. CAR imaging can be performed on SPR imaging setups. Through a side-by-side comparison, we show that CAR is capable of most molecular interaction measurements that SPR performs, including proteins, nucleic acids and cell-based detections. In addition, we show that CAR can detect small molecule bindings and intracellular signals beyond SPR sensing range. CAR exhibits several distinct characteristics, including tunable sensitivity and dynamic range, deeper vertical sensing range, fluorescence compatibility, broader wavelength and polarization of light selection, and glass surface chemistry. We anticipate CAR can expand SPR's capability in small molecule detection, whole cell-based detection, simultaneous fluorescence imaging, and broader conjugation chemistry.


Assuntos
Técnicas Biossensoriais/métodos , Vidro/química , Refratometria/métodos , Ressonância de Plasmônio de Superfície/métodos , Algoritmos , Linhagem Celular Tumoral , Células HeLa , Humanos , Ácidos Nucleicos/química , Ligação Proteica , Proteínas/química , Propriedades de Superfície
5.
Colloids Surf B Biointerfaces ; 205: 111886, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34091371

RESUMO

Guided bone regeneration (GBR) is widely used to treat oral bone defects. However, the osteogenic effects are limited by the deficiency of the available barrier membranes. In this study, a novel bi-layer membrane was prepared by solvent casting and electrospinning. The barrier layer made of poly (lactic-co-glycolic acid) (PLGA) was smooth and compact, whereas the osteogenic layer consisting of micro-nano bioactive glass (MNBG) and PLGA was rough and porous. The mineralization evaluation confirmed that apatite formed on the membranes in simulated body fluid. Immersion in phosphate-buffered saline led to the degradation of the membranes with proper pH changes. Mechanical tests showed that the bi-layered membranes have stable mechanical properties under dry and wet conditions. The bi-layered membranes have good histocompatibility, and the MNBG/PLGA layer can enhance bone regeneration activity. This was confirmed by cell culture results, expression of osteogenic genes, and immunofluorescence staining of RUNX-related transcription factor 2 and osteopontin. Therefore, the bi-layered membranes could be a promising clinical strategy for GBR surgery.


Assuntos
Materiais Biocompatíveis , Regeneração Tecidual Guiada , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Vidro , Membranas Artificiais , Osteogênese , Porosidade
6.
Injury ; 52 Suppl 3: S23-S28, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34116851

RESUMO

INTRODUCTION: Bioactive glass S53P4 (BAG-S53P4) has been used in the treatment of osteomyelitis with excellent results. The aim of this study was to evaluate the clinical and radiographic results of patients treated with use of antibiotic-loaded cement beads, followed by bone defects filling using bioglass. METHODS: We treated a prospective series of patients presenting with acute or chronic osteomyelitis of a long bone of the upper or lower limb. The first-stage procedure involved debridement and filling of cavitary defects with antibiotic-loaded polymethylmethacrylate (PMMA) beads. When signs of infection subsided, the defects were filled with BAG-S53P4. The main outcomes assessed were the reinfection rate, need for reoperation, radiographic and functional evaluations (DASH and Lysholm scores). RESULTS: Ten patients were included, aged between 4 and 66 years (mean 25.4 years). The source of infection was hematogenic in five cases and post-traumatic in the other five. Hematogenic infections required two debridements before filling with bioglass, whereas post-traumatic cases required only one. The time between the first debridement and the application of bioglass varied from 1 to 63 weeks (average of 17 weeks). All patients showed a favorable evolution after bioglass procedure, with no need for reoperation or relevant wound problems. The radiographic evaluation showed partial incorporation of the material and adequate bone formation, and functional scores were satisfactory in all cases. CONCLUSION: The treatment of osteomyelitis with surgical debridement and PMMA beads, followed by filling of bone defect with BAG-S53P4, was effective in all patients evaluated, with adequate infectious control and bone regeneration. No cases required reoperation after bioglass implantation. Patients with hematogenous osteomyelitis required a greater number of debridements before filling with bioglass.


Assuntos
Substitutos Ósseos , Osteomielite , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Desbridamento , Seguimentos , Vidro , Humanos , Pessoa de Meia-Idade , Osteomielite/diagnóstico por imagem , Osteomielite/tratamento farmacológico , Osteomielite/cirurgia , Estudos Prospectivos , Adulto Jovem
7.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073377

RESUMO

Bioactive glasses (BGs) are being increasingly considered for biomedical applications. One convenient approach to utilize BGs in tissue engineering and drug delivery involves their combination with organic biomaterials in order to form composites with enhanced biocompatibility and biodegradability. In this work, mesoporous bioactive glass nanoparticles (MBGN) have been merged with polyhydroxyalkanoate microspheres with the purpose to develop drug carriers. The composite carriers (microspheres) were loaded with curcumin as a model drug. The toxicity and delivery rate of composite microspheres were tested in vitro, reaching a curcumin loading efficiency of over 90% and an improving of biocompatibility of different concentrations of MBGN due to its administrations through the composite. The composite microspheres were tested in terms of controlled release, biocompatibility and bioactivity. Our results demonstrate that the composite microspheres can be potentially used in biomedicine due to their dual effects: bioactivity (due to the presence of MBGN) and curcumin release capability.


Assuntos
Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Vidro , Nanopartículas/química , Poliésteres/química , Linhagem Celular , Curcumina , Portadores de Fármacos , Durapatita/química , Emulsões , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Microesferas , Osteoblastos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Difração de Raios X
8.
Soft Matter ; 17(26): 6326-6336, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34136896

RESUMO

Interactions between colloidal-scale structures govern the physical properties of soft and biological materials, and knowledge of the forces associated with these interactions is critical for understanding and controlling these materials. A common approach to quantify colloidal interactions is to measure the interaction forces between colloids and a fixed surface. The centrifuge force microscope (CFM), a miniaturized microscope inside a centrifuge, is capable of performing hundreds of force measurements in parallel over a wide force range (10-2 to 104 pN), but CFM instruments are not widely used to measure colloid-surface interaction forces. In addition, current CFM instruments rely on brightfield illumination and are not capable of fluorescence microscopy. Here we present a fluorescence CFM (F-CFM) that combines both fluorescence and brightfield microscopy and demonstrate its use for measuring microscale colloidal-surface interaction forces. The F-CFM operates at speeds up to 5000 RPM, 2.5× faster than those previously reported, yielding a 6.25× greater maximum force than previous instruments. A battery-powered GoPro video camera enables real-time viewing of the microscopy video on a mobile device, and frequency analysis of the audio signal correlates centrifuge rotational speed with the video signal. To demonstrate the capability of the F-CFM, we measure the force required to detach hundreds of electrostatically stabilized colloidal microspheres attached to a charged glass surface as a function of ionic strength and compare the resulting force distributions with an approximated DLVO theory. The F-CFM will enable microscale force measurements to be correlated with fluorescence imaging in soft and biological systems.


Assuntos
Coloides , Vidro , Centrifugação , Microscopia de Força Atômica , Microscopia de Fluorescência
9.
Prog Orthod ; 22(1): 15, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34180030

RESUMO

BACKGROUND: Based on the role of properties of aligner materials on their efficiency, we aimed to assess their thermomechanical properties after thermoforming and simulated aging. METHODS: In this experimental study, 96 samples of polyethylene terephthalate glycol (PETG) aligners (Duran and Erkodur) were prepared and divided to three groups: control (C), after thermoforming (T), after thermoforming and aging (TA). Thermoforming was done through 3D-printed molds, and aging was exerted by 200 thermal cycles after immersion in 37°C distilled water for 24h. Flexural modulus, hardness, glass transition temperature (Tg), elastic and viscous modulus, and loss factor were evaluated. Two-way ANOVA, T-independent, and Tukey HSD tests were done for statistical analysis and significance level was set to 0.05. RESULTS: In both materials, flexural modulus decreased significantly after thermoforming, 88% in Duran and 70% in Erkodur, but did not change significantly after aging. After thermoforming, hardness decreased significantly in both materials (22% in Duran and 7.6% in Erkodur). Dynamic Tg was significantly lower in T and TA in both materials. At all temperatures (25, 37, 55°C) in Duran, the elastic modulus difference was only significant between C and TA, but in Erkodur, it decreased significantly in T, and there was no significant change after aging. Viscous modulus and loss factor showed the same change patterns at all temperatures. In both materials, they increased after thermoforming, but did not change significantly after aging. CONCLUSION: Thermoforming had more prominent role than aging in diminishing of thermomechanical properties. In general, Duran had greater thermomechanical stability than Erkodur.


Assuntos
Envelhecimento , Aparelhos Ortodônticos Removíveis , Resinas Compostas , Módulo de Elasticidade , Vidro , Dureza , Humanos , Teste de Materiais , Propriedades de Superfície
10.
Mater Sci Eng C Mater Biol Appl ; 126: 111856, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082925

RESUMO

Treatment of bone disease and disorders is often challenging due to its complex structure. Each year millions of people needs bone substitution materials with quick recovery from diseases conditions. Synthetic bone substitutes mimicking structural, chemical and biological properties of bone matrix structure will be very obliging and of copious need. In this work, we reported on the fabrication of bioinspired, biomimetic, multifunctional bone-like three-dimensional (3D) membranes made up of inorganic bioactive glass fibers matrixed organic collagen structure. The 3D structure is arranged as a stacked-layer similar to the order of apatite and neotissue formation. Comparative studies on collagen, collagen with hollow and solid bioactive glass fibers evidenced that, collagen/hollow bioactive glass is mechanically robust, has optimal hydrophilicity, simultaneously promotes bioactivity and in situ forming drug delivery. The 3D membrane displays outstanding mechanical properties apropos to the bioactive glass fibers arrangement, with its Youngs modulus approaching the modulus of cortical bone. The in vitro cell culture studies with fibroblast cells (3T3) on the membranes display enhanced cell adhesion and proliferation with the cell alignment similar to anisotropic cell alignment found in the native bone extracellular matrix. The membranes also support 3D cell culturing and exhibits cell proliferation on the membrane surface, which extends the possibility of its bone tissue engineering application. The alkaline phosphatase assessment and alizarin red staining of osteoblast cells (MG63) depicted an enhanced osteogenic activity of the membranes. Notable Runx2, Col-Type-1 mRNA, osteocalcin, and osteonectin levels were found to be significantly increased in cells grown on the collagen/hollow bioactive glass membrane. This membrane also promotes vascularization in the chick chorioallantoic membrane model. The results altogether evidence this multifunctional 3D membrane could potentially be utilized for treatment of bone defects.


Assuntos
Osso e Ossos , Vidro , Osteoblastos , Engenharia Tecidual , Linhagem Celular , Colágeno , Humanos , Osteogênese , Tecidos Suporte
11.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068186

RESUMO

We report a label-free and simple approach for the detection of glycoprotein-120 (gp-120) using an aptamer-based liquid crystals (LCs) biosensing platform. The LCs are supported on the surface of a modified glass slide with a suitable amount of B40t77 aptamer, allowing the LCs to be homeotropically aligned. A pronounced topological change was observed on the surface due to a specific interaction between B40t77 and gp-120, which led to the disruption of the homeotropic alignment of LCs. This results in a dark-to-bright transition observed under a polarized optical microscope. With the developed biosensing platform, it was possible to not only identify gp-120, but obtained results were analyzed quantitatively through image analysis. The detection limit of the proposed biosensing platform was investigated to be 0.2 µg/mL of gp-120. Regarding selectivity of the developed platform, no response could be detected when gp-120 was replaced by other proteins, such as bovine serum albumin (BSA), hepatitis A virus capsid protein 1 (Hep A VP1) and immunoglobulin G protein (IgG). Due to attributes such as label-free, high specificity and no need for instrumental read-out, the presented biosensing platform provides the potential to develop a working device for the quick detection of HIV-1 gp-120.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Proteína gp120 do Envelope de HIV/análise , Cristais Líquidos/química , Calibragem , Vidro/química , HIV-1 , Humanos , Microscopia de Força Atômica , Imagem Óptica , Propriedades de Superfície
12.
Stomatologiia (Mosk) ; 100(3): 35-39, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34180623

RESUMO

THE AIM OF THE STUDY: Was to assess the clinical effectiveness of the course use of toothpaste with NovaMin by smoking and nonsmoking patients along with its complex effects on the oral cavity. MATERIALS AND METHODS: 75 young patients (46 males and 29 females, mean age 23.95±2.9 years) were divided into three groups of 25 individuals. The first group was composed of non-smoking patients using toothpaste with NovaMin. The second group (reference group) comprised patients using placebo toothpaste. The third group was composed of smoking patients using toothpaste with NovaMin. The clinical trials of patients included assessment of functional activity of minor salivary glands, the sialometric analysis, the study on microcrystallization of mixed saliva. The non-specific resistance of oral cavity was studied based on the analysis of absorption reaction of microorganisms by epithelial cells. All patients were questioned about the organoleptic characteristics of the toothpaste. The abovementioned features were assessed before the study, after the first use of the toothpaste, after day 7 and day 14. RESULTS: The course use of toothpaste with NovaMin resulted in the plaque inhibiting effect (p≤0.05), increased functional activity of minor salivary glands (p≤0.05) promoting increased salivation and oral cavity cleansing. The concept of local recovery of the receptor apparatus of epithelial cells is confirmed for the first group of patients; the non-specific resistance in tobacco users is low, prevalence of Type I epithelial cells is defined (p≤0.05). CONCLUSION: The evaluated toothpaste affects metabolism in the oral cavity because it was diagnosed that the non-specific resistance of the oral cavity and absorption by epithelia improved in all patients after the course use.


Assuntos
Tabaco , Cremes Dentais , Adulto , Feminino , Vidro , Humanos , Masculino , Boca , Adulto Jovem
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120075, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34153548

RESUMO

Tellurite glasses with combination of Er3+/Tm3+/Nd3+ ions and silver nanoparticles (Ag NPs) were prepared by using single-step melt-quenching technology, and the enhanced effect of Ag NPs on the ultra-broadband near-infrared (NIR) fluorescence was studied. Under the 808 nm LD excitation, two ultra-broadband NIR fluorescence of 1300-1600 nm and 1600-2100 nm underwent an obvious enhancement of about 52% compared to the tri-doping tellurite glass free of Ag NPs. The intensified local electric field induced by Ag NPs together with the energy transfer from Ag species to doped ions is responsible for this enhancement. The enhanced ultra-broadband NIR fluorescence of 1300-1600 nm with the full width at half maximum (FWHM) of 230 nm, originating from the spectral overlapping of 1.34 µm (4F3/2→4I13/2 of Nd3+), 1.47 µm (3H4→3F4 of Tm3+) and 1.53 µm (4I13/2→4I15/2 of Er3+) three bands, is promising in developing new ultra-broadband photonic devices such as fiber amplifiers and tunable lasers.


Assuntos
Nanopartículas Metálicas , Prata , Vidro , Telúrio
14.
J Mech Behav Biomed Mater ; 120: 104567, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33945937

RESUMO

An oligomer with short organic molecular chains was successfully synthesized with KH550 and KH560. This oligomer was combined with tetraethyl orthosilicate and calcium chloride to prepare an organic-inorganic hybrid biological material (OI-BM) by sol-gel chemistry. The hybrid was fully characterized by a series of instrumental characterizations including nuclear magnetic resonance spectrometry, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray energy spectroscopy and inductively coupled plasma spectrometry. OI-BM presented elastic deformation under compression. The elastic modulus and ultimate stress of OI-BM were 0.4 ± 0.1 GPa and 23.0 ± 4.0 MPa, respectively, lower than those of 45S5 bioactive glass (45S5-BG), whereas the strain at failure and modulus of toughness of OI-BM was about 4.5 times and 4 times higher. The hybrid is easy to form due to the improved mechanical property, suggesting excellent machining properties. The hybrid OI-BM produced hydroxyapatite in 1 h in simulated body fluid due to its excellent bioactivity. CCK-8 assay further demonstrated the desirable cytocompatibility of the hybrid. Thus, the hybrid can be a potential material for satisfying the mechanical property requirement of an implant.


Assuntos
Durapatita , Vidro , Módulo de Elasticidade , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
15.
J Laryngol Otol ; 135(6): 492-500, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33975661

RESUMO

OBJECTIVE: To compare the efficacy of bone pâté versus bioactive glass in mastoid obliteration. METHOD: This randomised parallel groups study was conducted at a tertiary care centre between September 2017 and August 2019. Sixty-eight patients, 33 males and 35 females, aged 12-56 years, randomly underwent single-stage canal wall down mastoidectomy with mastoid obliteration using either bone pâté (n = 35) or bioactive glass (n = 33), and were evaluated 12 months after the operation. RESULTS: A dry epithelised cavity (Merchant's grade 0 or 1) was achieved in 65 patients (95.59 per cent). Three patients (4.41 per cent) showed recidivism. The mean air-bone gap decreased to 16.80 ± 4.23 dB from 35.10 ± 5.21 dB pre-operatively. The mean Glasgow Benefit Inventory score was 30.02 ± 8.23. There was no significant difference between the two groups in these outcomes. However, the duration of surgery was shorter in the bioactive glass group (156.87 ± 7.83 vs 162.28 ± 8.74 minutes; p = 0.01). CONCLUSION: The efficacy of both materials was comparable.


Assuntos
Transplante Ósseo , Vidro , Mastoidectomia/métodos , Otite Média/cirurgia , Adolescente , Adulto , Criança , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Adulto Jovem
16.
Mater Sci Eng C Mater Biol Appl ; 124: 112050, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33947544

RESUMO

In recent years, mesoporous bioactive glass nanoparticles (MBGNPs) have generated great attention in biomedical applications. In this study, cerium and gallium doped MBGNPs were prepared by microemulsion assisted sol-gel method in the binary SiO2-CaO system. MBGNPs with spheroidal and pineal shaped morphology were obtained. Nitrogen sorption analysis elucidated the mesoporous structure of synthesized nanoparticles with high specific surface area. X-ray diffraction analysis confirmed the amorphous nature of the nanoparticles. The chemical compositions of all samples were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES), which revealed that the contents of cerium and gallium could be tailored by adjusting the concentrations of the precursors used for the synthesis. All MBGNPs exhibited in vitro bioactivity when immersed in simulated body fluid, except the particles doped with higher amounts than 1 mol% of cerium. MBGNPs showed antibacterial activity against S. aureus and E. coli without exhibiting cytotoxicity towards MG-63 osteoblast-like cells. Mentioned features of the obtained Ce and Ga-doped MBGNPs make them useful for multifunctional applications such as drug delivery carriers or bioactive fillers for bone tissue engineering applications.


Assuntos
Cério , Gálio , Nanopartículas , Antibacterianos/farmacologia , Regeneração Óssea , Escherichia coli , Gálio/farmacologia , Vidro , Dióxido de Silício , Staphylococcus aureus
17.
Mater Sci Eng C Mater Biol Appl ; 124: 112060, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33947554

RESUMO

This work reports a new CaO-MgO-SiO2 (CMS) bioactive glass-ceramic, using ZrO2 as a nucleus to modulate the ratios of glass and ceramic phases as a function of sintering temperature. Mg-rich bioactive CMS glass-ceramics exhibit advantages regarding mechanical strength (flexural strength ~190 MPa and compressive strength ~555 MPa), in-vitro and in-vivo biocompatibilities, and bone ingrowth. The high mechanical strengths could be attributed to the CaMgSi2O6 glass-ceramic and lower porosity. X-ray absorption spectra indicate an increased SiO covalent bond via the development of CaMgSi2O6 glass-ceramics. From the in-vitro cytotoxicity and BMSC differentiation assays, the CMS samples sintered above 800 °C exhibited better cell attachment and differentiation, possibly due to structural stability, appropriate pore, and ion release to boost osteogenesis. Compared to hydroxyapatite (HA) ceramics, the CMS glass-ceramics display higher mechanical strengths, biocompatibility, and osteoconductivity. An in-vivo experiment demonstrated a fine bone-ingrowth profile around the CMS implant. This study may further the application of CMS glass-ceramics in bone implants.


Assuntos
Óxido de Magnésio , Dióxido de Silício , Cerâmica , Durapatita , Vidro
18.
Curr Protoc ; 1(5): e108, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33945676

RESUMO

The preparation of controlled pore glass (CPG) supports, functionalized with several hexaethylene glycol spacers, to alleviate the problems associated with the porosity of commercial CPG supports is described in this article. The pore size of CPG restricts the diffusion of reagents to the leader nucleoside embedded in porous supports; this inhibits efficient solid-phase syntheses of DNA and RNA sequences and, by default, the purity of those sequences through formation of a shorter than full-length oligonucleotide. Functionalization of a CPG support with five hexaethylene glycol spacers led to a 42% reduction in process-related impurities contaminating oligonucleotide sequences, compared to that obtained using the commercial long-chain alkylamine (LCAA) CPG support. © 2021 Wiley Periodicals LLC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. Basic Protocol 1: Preparation of the hydroxylated CPG support 3 Basic Protocol 2: Automated preparation of the CPG support 6 Basic Protocol 3: Automated preparation of the poly(hexaethylene glycol)-derived CPG 7 Basic Protocol 4: Automated functionalization of the poly(hexaethylene glycol)-derived CPG support 7 with leader deoxyribo- and ribonucleosides to provide the CPG support 9 Basic Protocol 5: Automated syntheses of DNA and RNA sequences on poly(hexaethylene glycol)-derived CPG support 9 and on a commercial long-chain alkylamine (LCAA) CPG support Support Protocol: Release and deprotection of the DNA and RNA sequences linked to the poly(hexaethylene glycol)-derived CPG support 10 and commercial LCAA-CPG support Basic Protocol 6: Comparative RP-HPLC analyses of crude, fully deprotected DNA or RNA sequences released from the poly(hexaethylene glycol)-derived CPG support 10 and from a commercial LCAA-CPG support.


Assuntos
DNA , Técnicas de Síntese em Fase Sólida , Sequência de Bases , Vidro , Oligonucleotídeos
19.
J Colloid Interface Sci ; 598: 464-473, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951546

RESUMO

HYPOTHESIS: Interaction of cellular membranes with biointerfaces is of vital importance for a number of medical devices and implants. Adhesiveness of these surfaces and cells is often regulated by depositing a layer of bovine serum albumin (BSA) or other protein coatings. However, anomalously large separations between phospholipid membranes and the biointerfaces in various conditions and buffers have been observed, which could not be understood using available theoretical arguments. METHODS: Using the Lifshitz theory, we here evaluate the distance-dependent Hamaker coefficient describing the dispersion interaction between a biointerface and a membrane to understand the relative positioning of two surfaces. Our theoretical modeling is supported by experiments where the biointerface is represented by a glass substrate with deposited BSA and protein layers. These biointerfaces are allowed to interact with giant unilamellar vesicles decorated with polyethylene glycol (PEG) using PEG lipids to mimic cellular membranes and their pericellular coat. RESULTS: We demonstrate that careful treatment of the van der Waals interactions is critical for explaining the lack of adhesiveness of the membranes with protein-decorated biointerfaces. We show that BSA alone indeed passivates the glass, but depositing an additional protein layer on the surface BSA, or producing multiple layers of proteins and BSA results in repulsive dispersion forces responsible for 100 nm large equilibrium separations between the two surfaces.


Assuntos
Polietilenoglicóis , Soroalbumina Bovina , Adesividade , Vidro
20.
Food Chem ; 359: 129935, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33934032

RESUMO

To understand the specific contributions of amorphous sugars and organic acids to the quality of food matrix, the solid model system of jujube slice skeleton (JSS) was firstly established. Effects of fructose (F), glucose (G), malic acid (M) and citric acid (C) on the glass transition temperature (Tg) and crystallization of JSS were studied. JSS-F/G/M/C blends were prepared by osmosis in the solution at a range of 0 ~ 32 g/100 g. Sugars reduced the Tg in the system, structure of JSS-G/M blends was changed from "amorphous glassy" to "amorphous rubbery" by increasing the osmotic solute concentration. Tg was decreased from 50.8 to 14.0 °C when JSS was osmosed in a 4 g/100 g fructose solution. Organic acids induced their crystallization in JSS. The crystallinity of JSS-M immersed in 32 g/100 g osmotic solution concentration was increased from 2% to 75%. Fructose presented greater influence on the adverse quality of jujube slices.


Assuntos
Ácidos/química , Compostos Orgânicos/química , Açúcares/química , Temperatura de Transição , Vitrificação , Ziziphus/química , Varredura Diferencial de Calorimetria , Cristalização , Vidro/química , Temperatura , Água/química
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