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1.
J Periodontal Res ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634181

RESUMO

AIMS: Despite the established use of palatal tissue grafts for mucogingival procedures, there are no studies on the effect of extraoral storage time on graft outcomes. This prospective split-mouth randomized experimental clinical trial aimed to assess whether gingival graft extraoral storage time affects graft healing. METHODS: Standardized grafts were harvested from the palate and stored extraorally for 2 (Control) or 40 (Test) minutes before being placed at recipient beds. Intraoral scans, clinical photographs, and tissue blood perfusion were obtained preoperatively, postoperatively, and at follow-up visits (Days 2 (PO2), 3 (PO3), 7 (PO7), and 14 (PO14)). Healing Score Index (HSI) and wound fluid (WF) biomarkers (angiogenin, IL-6, IL-8 (CXCL8), IL-33, VEGF-A, and ENA-78 (CXCL5)) were also assessed. RESULTS: Twenty-three participants completed all study visits. Extraoral storage time was 2.3 ± 1.1 min and 42.8 ± 3.4 min for C and T grafts, respectively (p < .0001). Recipient beds remained open for 21.4 ± 1.7 min. No graft underwent necrosis or failed to heal by PO14. Minimal volumetric changes were observed, without significant intergroup differences (p ≥ .11). Graft perfusion initially decreased post-harvesting before peaking on PO7 for both C and T grafts, with no significant intergroup differences (p ≥ .14). HSI values progressively increased, with no significant intergroup differences (p ≥ .22). WF analysis revealed detectable levels for all biomarkers tested, without significant intergroup differences (p ≥ .23). CONCLUSION: Extraoral storage time of 40 min has neither statistically significant nor clinically discernible effects on autologous graft revascularization, early healing, or survival, as determined by physiological, wound healing, and molecular parameters.

2.
Altern Ther Health Med ; 30(5): 65-70, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38401097

RESUMO

Objective: To analyze the short-term and long-term efficacy of Osteoset artificial bone graft fusion mixed with rifampicin for injection in the treatment of sacroiliac joint tuberculosis. Methods: A retrospective analysis was carried out on 70 patients diagnosed with sacroiliac joint tuberculosis who were admitted and underwent surgical treatment in our orthopedics department between April 2014 and May 2020. The patients were divided into three groups based on the different bone graft materials used: autogenous bone graft group (25 cases), simple lesion removal group (18 cases), and drug-loaded calcium sulfate bone graft group (27 cases). General information and surgical details of the three groups were compared. Sacroiliac X-ray and CT scans were performed at regular intervals to record pre- and post-treatment erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels, bone graft fusion rates at 6, 12, and 18 months post-surgery, Majeed score for functional evaluation, and postoperative complications. Results: There was no statistically significant difference in operation time, intraoperative bleeding, and intraoperative pus removal volume among the three groups of patients (P > .05). Postoperatively, 70 patients were followed up, and the serum levels of ESR and CRP in all three groups of patients were significantly reduced at 3 months after surgery (P < .05). In the autogenous bone graft group, the bone graft fusion rates were 24.00% (6/25) at 6 months postoperatively, 76.00% (18/25) at 12 months, and 96.00% (24/25) at 18 months. In the simple lesion removal group, the bone graft fusion rates were 16.67% (3/18) at 6 months postoperatively, 27.78% (5/18) at 12 months, and 55.56% (10/18) at 18 months. In the drug-loaded calcium sulfate bone graft group, the bone graft fusion rates were 18.52% (5/27) at 6 months postoperatively, 55.56% (15/27) at 12 months, and 81.48% (22/27) at 18 months. In the autogenous bone graft group, the postoperative Majeed score averaged (91.47±4.13) points, with 13 cases rated as excellent and 10 cases rated as good, resulting in an excellent and good rate of 92.00% (23/25). The Majeed scores at 6, 12, and 18 months postoperatively were (67.19±4.22) points, (80.28±5.83) points, and (91.47±4.13) points, respectively. Among them, there were 4 excellent and 3 good cases at 6 months postoperatively, with an excellent and good rate of 28.00% (7/25). At 12 months postoperatively, there were 8 excellent and 10 good cases, with an excellent and good rate of 72.00% (18/25). At 18 months postoperatively, there were 13 excellent and 10 good cases, with an excellent and good rate of 92.00% (23/25). In the simple lesion removal group, the Majeed scores at 6, 12, and 18 months postoperatively were (59.17±3.95) points, (69.84±5.16) points, and (76.22±8.76) points, respectively. There were 2 excellent and 2 good cases at 6 months postoperatively, with an excellent and good rate of 22.22% (4/18). At 12 months postoperatively, there were 4 excellent and 3 good cases, with an excellent and good rate of 38.89% (7/18). At 18 months postoperatively, there were 5 excellent and 5 good cases, with an excellent and good rate of 55.56% (10/18). In the drug-loaded calcium sulfate bone graft group, the Majeed scores at 6, 12, and 18 months postoperatively were (63.24±4.17) points, (77.39±5.50) points, and (86.64±7.03) points, respectively. There were 3 excellent and 3 good cases at 6 months postoperatively, with an excellent and good rate of 22.22% (6/27). At 12 months postoperatively, there were 9 excellent and 7 good cases, with an excellent and good rate of 59.26% (16/27). At 18 months postoperatively, there were 10 excellent and 12 good cases, with an excellent and good rate of 81.48% (22/27). The Majeed scores for all three groups of patients showed a significant increase in the three follow-up evaluations compared to pre-treatment (P < .05). Conclusion: Drug-loaded Osteoset artificial bone graft fusion is a safe and effective method for treating bone defects after the debridement of sacroiliac joint tuberculosis lesions. It has fewer postoperative complications and achieves bone graft fusion in a shorter time compared to simple lesion removal methods.


Assuntos
Transplante Ósseo , Articulação Sacroilíaca , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Transplante Ósseo/métodos , Pessoa de Meia-Idade , Articulação Sacroilíaca/cirurgia , Rifampina/uso terapêutico , Tuberculose Osteoarticular/tratamento farmacológico , Tuberculose Osteoarticular/cirurgia , Resultado do Tratamento , Substitutos Ósseos/uso terapêutico
3.
Acc Chem Res ; 55(16): 2291-2303, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35899979

RESUMO

Fluorescent polymer hydrogels (FPHs) are of significant interest for diverse emerging applications such as visualized sensing, smart display, camouflaging skins, soft actuators/robots, because they can synergize the features of classic fluorescent polymers and hydrogels. With great efforts in the past decades, the major challenge in this field has been believed to be not whether a given FPH of interest can be prepared but how to fabricate robust FPHs with multicolor tunability and multifunctional synergy. Such materials will conceptually minimize the contribution of passive materials to the mass and size of the final system, holding great potential to facilitate multiple applications. To this end, one promising way is to learn from the Nature that has superb capability to forge delicate or sometimes beyond-imagination materials. Chameleons and cephalopods serve as typical examples, which are famous for not only diverse skin color adaptability under changing environmental demands, but also synergistic skin color and body gesture changes to communicate, warn, camouflage, etc. Biological studies revealed their structural color-changing capacity derives from different types of skin chromatophores and their rational multilayer arrangement in under-skin tissues. Besides, their superb ability to heterogeneously integrate soft tissues with disparate functions into topology-optimized architectures has led to various multifunctional performances. Such natural strategies, if replicated and implemented in artificial systems, would significantly benefit and advance the development of robust FPHs for various applications.In this Account, we summarizes the key advances of smart FPHs mainly achieved by our groups. We start by introducing the unique hierarchical multilayer structures of skin chromatophores in structural color-changing reptiles, followed by an in-depth discussion on how a rational integration of bioinspiration and man-made design makes it possible to largely expand the fluorescence color-changing range of smart FPHs to almost cover the whole visible spectrum. Then, to closely mimic the multifunctional behaviors of chameleons and cephalopods, we further develop efficient strategies to introduce supramolecular interactions or heterogeneously integrating smart FPHs with other soft materials with disparate functions, producing a number of multifunctional fluorescent polymeric hydrogel systems. These robust FPHs can find many frontier applications, including bioinspired synergistic color/shape switchable hydrogel actuators/robots, smart systems with on-demand fluorescent patterning capacities for displaying or information encryption, as well as robust chemosensors for important food or environmental analytes. We expect that the discussion presented in this Account would promote better understanding of the discoloration systems in nature, and advance the development of bioinspired color-changing materials.


Assuntos
Materiais Biomiméticos , Hidrogéis , Materiais Biomiméticos/química , Corantes , Fluorescência , Humanos , Hidrogéis/química , Polímeros/química , Pele
4.
Oral Dis ; 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38148479

RESUMO

OBJECTIVES: To explore the role of fibrocytes in the recurrence and calcification of fibrous epulides. METHODS: Different subtypes of fibrous epulides and normal gingival tissue specimens were first collected for histological and immunofluorescence analyses to see if fibrocytes were present and whether they differentiated into myofibroblasts and osteoblasts upon stimulated by transforming growth factor-ß1 (TGF-ß1). Electron microscopy and elemental analysis were used to characterize the extracellular microenvironment in different subtypes of fibrous epulides. Human peripheral blood mononuclear cells (PBMCs) were subsequently isolated from in vitro models to mimic the microenvironment in fibrous epulides to identify whether TGF-ß1 as well as the calcium and phosphorus ion concentration in the extracellular matrix (ECM) of a fibrous epulis trigger fibrocyte differentiation. RESULTS: Fibrous epulides contain fibrocytes that accumulate in the local inflammatory environment and have the ability to differentiate into myofibroblasts or osteoblasts. TGF-ß1 promotes fibrocytes differentiation into myofibroblasts in a concentration-dependent manner, while TGF-ß1 stimulates the fibrocytes to differentiate into osteoblasts when combined with a high calcium and phosphorus environment. CONCLUSIONS: Our study revealed fibrocytes play an important role in the fibrogenesis and osteogenesis in fibrous epulis, and might serve as a therapeutic target for the inhibition of recurrence of fibrous epulides.

5.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675053

RESUMO

Asparagus belongs to the Liliaceae family and has important economic and pharmacological value. Lignin plays a crucial role in cell wall structural integrity, stem strength, water transport, mechanical support and plant resistance to pathogens. In this study, various biological methods were used to study the mechanism of shading on the asparagus lignin accumulation pathway. The physiological results showed that shading significantly reduced stem diameter and cell wall lignin content. Microstructure observation showed that shading reduced the number of vascular bundles and xylem area, resulting in decreased lignin content, and thus reducing the lignification of asparagus. Cinnamic acid, caffeic acid, ferulic acid and sinapyl alcohol are crucial intermediate metabolites in the process of lignin synthesis. Metabolomic profiling showed that shading significantly reduced the contents of cinnamic acid, caffeic acid, ferulic acid and sinapyl alcohol. Transcriptome profiling identified 37 differentially expressed genes related to lignin, including PAL, C4H, 4CL, CAD, CCR, POD, CCoAOMT, and F5H related enzyme activity regulation genes. The expression levels of POD, CCoAOMT, and CCR genes were significantly decreased under shading treatment, while the expression levels of CAD and F5H genes exhibited no significant difference with increased shading. The downregulation of POD, CCoAOMT genes and the decrease in CCR gene expression levels inhibited the activities of the corresponding enzymes under shading treatment, resulting in decreased downstream content of caffeic acid, ferulic acid, sinaperol, chlorogenic acid and coniferin. A significant decrease in upstream cinnamic acid content was observed with shading, which also led to decreased downstream metabolites and reduced asparagus lignin content. In this study, transcriptomic and metabolomic analysis revealed the key regulatory genes and metabolites of asparagus lignin under shading treatment. This study provides a reference for further understanding the mechanism of lignin biosynthesis and the interaction of related genes.


Assuntos
Adaptação Fisiológica , Asparagus , Lignina , Luz Solar , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Lignina/biossíntese , Lignina/genética , Lignina/metabolismo , Transcriptoma , Asparagus/genética , Asparagus/metabolismo , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia
6.
J Prosthet Dent ; 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37003942

RESUMO

A digital workflow for fabricating a polyetherketoneketone (PEKK) periodontal splint is described. The antibacterial properties of PEKK and the precision and efficiency of digital technology led to the provision of a splint with no adverse effects on oral hygiene or periodontal maintenance during a 2-year follow-up.

7.
J Prosthet Dent ; 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37596157

RESUMO

STATEMENT OF PROBLEM: Implementation of fabrication trueness analysis by using a recently introduced nonmetrology-grade freeware program may help clinicians and dental laboratory technicians in their routine practice. However, knowledge of the performance of this freeware program when compared with the International Organization for Standardization recommended metrology-grade analysis software program is limited. PURPOSE: The purpose of this in vitro study was to evaluate the effect of an analysis software program on measured deviations in the complete arch, implant-supported framework scans. MATERIAL AND METHODS: A total of 20 complete arch, implant-supported frameworks were fabricated from a master standard tessellation language (STL) file from either polyetheretherketone (PEEK) or titanium (Ti) (n=10). All frameworks were then digitized by using different scanners to generate test STLs. All STL files were imported into a nonmetrology-grade freeware program (Medit Link) and a metrology-grade software program (Geomagic Control X) to measure the overall and marginal deviations of frameworks from the master STL file by using the root mean square (RMS) method. Data were analyzed by using the two 1-sided paired t test procedure, in which 50 µm was considered as the minimal clinically meaningful difference (α=.05). RESULTS: When overall RMS values were considered, the nonmetrology-grade freeware program was not inferior to the metrology-grade software program (P<.05). When marginal RMS values were considered, the nonmetrology-grade freeware program was inferior to the metrology-grade software program only when PEEK frameworks were scanned with an E4 laboratory scanner (P>.05). CONCLUSIONS: The use of the tested nonmetrology-grade freeware program resulted in overall deviation measurements similar to those when a metrology-grade software program was used. The freeware program was inferior when marginal deviations were analyzed on E4 scans of a PEEK framework, which was the only scanner-material pair that led to a significant difference, among the 15 pairs tested.

8.
Am J Orthod Dentofacial Orthop ; 164(1): 24-33, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36801092

RESUMO

INTRODUCTION: This research project aimed to compare the number of maxillary incisors and canine movement between Invisalign and fixed orthodontic appliances using artificial intelligence and identify any limitations of Invisalign. METHODS: Sixty patients (Invisalign, n = 30; braces, n = 30) were randomly selected from the Ohio State University Graduate Orthodontic Clinic archive. Peer Assessment Rating (PAR) analysis was used to indicate the severity of the patients in both groups. To analyze the incisors and canine movement, specific landmarks were identified on incisors and canines using an artificial intelligence framework, two-stage mesh deep learning. Total average tooth movement in the maxilla and individual (incisors and canine) tooth movement in 6 directions (buccolingual, mesiodistal, vertical, tipping, torque, rotation) were then analyzed at a significance level of α = 0.05. RESULTS: Based on the posttreatment Peer Assessment Rating scores, the quality of finished patients in both groups was similar. In maxillary incisors and canines, there was a significant difference in movement between Invisalign and conventional appliances for all 6 movement directions (P <0.05). The greatest differences were with rotation and tipping of the maxillary canine, along with incisor and canine torque. The smallest statistical differences observed for incisors and canines were crown translational tooth movement in the mesiodistal and buccolingual directions. CONCLUSIONS: When comparing fixed orthodontic appliances to Invisalign, patients treated with fixed appliances were found to have significantly more maxillary tooth movement in all directions, especially with rotation and tipping of the maxillary canine.


Assuntos
Aparelhos Ortodônticos Removíveis , Braquetes Ortodônticos , Maxila , Inteligência Artificial , Aparelhos Ortodônticos Fixos , Técnicas de Movimentação Dentária
9.
Biomacromolecules ; 23(5): 2075-2088, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35420791

RESUMO

Polysaccharides are abundant in nature and employed in various biomedical applications ranging from scaffolds for tissue engineering to carriers for drug delivery systems. However, drawbacks such as tedious isolation protocols, contamination, batch-to-batch consistency, and lack of compositional control with regards to stereo- and regioselectivity impede the development and utility of polysaccharides, and thus mimetics are highly sought after. We report a synthetic strategy to regioselectively functionalize poly-amido-saccharides with sulfate or phosphate groups using post-polymerization modification reactions. Orthogonally protected ß-lactam monomers, synthesized from D-glucal, undergo anionic ring-opening polymerization to yield polymers with degrees of polymerization of 12, 25, and 50. Regioselective deprotection followed by functionalization and global deprotection affords the sulfated and phosphorylated poly-amido-saccharides. The resulting anionic polymers are water soluble and non-cytotoxic and adopt helical conformations. This new methodology provides access to otherwise inaccessible functional polysaccharide mimetics for biomedical applications.


Assuntos
Carboidratos , Sulfatos , Polimerização , Polímeros , Polissacarídeos
10.
J Environ Manage ; 302(Pt A): 114044, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34735829

RESUMO

In order to solve the environmental problems caused by greenhouse gas emissions, cellulosenanofiber (CNF)/polyvinyl alcohol (PVA)/graphene oxide (GO) aerogel was obtained by step-by-step heating, tert-butanol replacement, freeze-drying, and high-temperature activation in this paper. The micromorphology, specific surface area, pore size distribution, and thermal stability of the prepared aerogels were analyzed by scanning electron microscopy, automatic surface area and porosity analysis, and thermo-gravimetric analysis. The interaction state and adsorption mechanism of CO2 and aerogel physical adsorption were described by Materials Studio simulation. The results showed that the adsorption process conformed to the Langmuir adsorption isotherm. After carbonization, the thermal stability of the aerogel was good (mass loss rate <1%). With the increase of GO content, its specific surface area increased (392.41 m2/g) and CO2 adsorption capacity increased (432.76 cm3/g at 273 K). The simulation results show that hydrogen bond energy and van der Waals adsorption are the main factors that help in adsorption of CO2 on the surface aerogel, and electrostatic adsorption is the secondary adsorption factor. The application of green material carbon-based aerogels is also in line with the concept of sustainable development.


Assuntos
Grafite , Álcool de Polivinil , Dióxido de Carbono , Simulação de Dinâmica Molecular
11.
J Prosthet Dent ; 128(3): 341-349, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33589234

RESUMO

STATEMENT OF PROBLEM: Strontium has been validated for potent bone-seeking and antiosteoporotic properties and elicits a potentially beneficial impact on implant osseointegration in patients with osteoporosis. However, the efficacy of strontium supplementation on improving new bone formation and implant osseointegration in the presence of osteoporotic bone is still unclear. PURPOSE: The purpose of this systematic review was to comprehensively assess the efficacy of strontium supplementation, encompassing oral intake and local delivery of strontium, on implant osseointegration in patients with osteoporosis. MATERIAL AND METHODS: Searches on electronic databases (MEDLINE or PubMed, Web of Science, EBSCO, Embase, and Clinicaltrials.gov) and manual searches were conducted to identify relevant preclinical animal trials up to June 2020. The primary outcomes were the percentage of bone-implant contact and bone area; the secondary outcomes were quantitative parameters of biomechanical tests and microcomputed tomography (µCT). RESULTS: Fourteen preclinical trials (1 rabbit, 1 sheep, and 12 rat), with a total of 404 ovariectomized animals and 798 implants, were eligible for analysis. The results revealed a significant 17.1% increase in bone-implant contact and 13.5% increase in bone area, favoring strontium supplementation despite considerable heterogeneity. Subgroup analyses of both bone-implant contact and bone area exhibited similar outcomes with low to moderate heterogeneity. Results of biomechanical and µCT tests showed that strontium-enriched implantation tended to optimize the mechanical strength and microarchitecture of newly formed bone despite moderate to generally high heterogeneity. CONCLUSIONS: Based on the available preclinical evidence, strontium supplementation, including local and systemic delivery, showed promising results for enhancing implant osseointegration in the presence of osteoporosis during 4 to 12 weeks of healing. Future well-designed standardized studies are necessary to validate the efficacy and safety of strontium supplementation and to establish a standard methodology for incorporating Sr into implant surfaces in a clinical setting.


Assuntos
Implantes Dentários , Osteoporose , Animais , Suplementos Nutricionais , Osseointegração , Osteoporose/tratamento farmacológico , Coelhos , Ratos , Ovinos , Estrôncio/uso terapêutico , Titânio/uso terapêutico , Microtomografia por Raio-X
12.
J Prosthet Dent ; 127(6): 823-826, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33483140

RESUMO

This clinical report describes the fabrication of conventional complete dentures with polyetherketoneketone (PEKK) frameworks made with computer-aided design and computer-aided manufacturing (CAD-CAM). No biologic or prosthetic complications were observed at the 1-year follow-up.


Assuntos
Planejamento de Dentadura , Prótese Total , Benzofenonas , Desenho Assistido por Computador , Polímeros
13.
J Prosthet Dent ; 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35636984

RESUMO

STATEMENT OF PROBLEM: Three-dimensional printing has facilitated the fabrication processes in dentistry. However, knowledge on the effect of layer thickness on the trueness of 3D-printed fixed partial dentures (FPDs) is lacking. PURPOSE: The purpose of this in vitro study was to compare the effect of printing layer thickness on the trueness of 3-unit interim FPDs fabricated by using additive manufacturing with that of those fabricated by subtractive manufacturing. MATERIAL AND METHODS: The right first premolar and first molar teeth of a dentate mandibular model were prepared for a 3-unit restoration and then digitized by using an intraoral scanner. A 3-unit interim FPD was designed to fabricate 40 restorations by using either the additive (NextDent C&B MFH) with layer thicknesses of 20 µm (n=10), 50 µm (n=10), and 100 µm (n=10) or subtractive manufacturing technique (Upcera) (milled, n=10). After fabrication, the interim FPDs were digitized by using the same intraoral scanner and were superimposed over the design data by using a 3D analysis software program. Root mean square (RMS) was used to analyze the trueness of the restorations at 4 different surfaces (external, intaglio, marginal area, and intaglio occlusal) and as a complete unit (overall). Data were analyzed with the Kruskal-Wallis and Wilcoxon tests with Bonferroni correction (α=.05). RESULTS: The 100-µm-layer thickness interim FPDs showed the greatest overall (P≤.015), external (P≤.021), and intaglio occlusal (P≤.021) deviations, whereas the milled interim FPDs showed the lowest (P=.001). No significant differences were found among the test groups for marginal RMS (P≥.108). The differences between the 50-µm-layer thickness and 100-µm-layer thickness interim FPDs for the intaglio surface deviations (P=.064) and between the 20-µm-layer thickness and 50-µm-layer thickness interim FPDs for each surface tested were not statistically significant (P≥.108). CONCLUSIONS: The printing layer thickness had a significant effect on the trueness of the additively manufactured interim FPDs. However, subtractively manufactured interim FPDs presented higher trueness than those additively manufactured, regardless of the printing layer thickness.

14.
J Mater Sci Mater Med ; 32(9): 100, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34406511

RESUMO

Polyvinyl alcohol (PVA) hydrogel has gained interest in cartilage repair because of its highly swollen, porosity, and viscoelastic properties. However, PVA has some deficiencies, such as its poor biocompatibility and microstructure. This research aimed to design novel hydroxyapatite (HA)-collagen (COL)-PVA hydrogels. COL was added to improve cell biocompatibility, and the microstructure of the hydrogels was controlled by fused deposition modeling (FDM). The feasibility of the COL-HA-PVA hydrogels in cartilage repair was evaluated by in vitro and in vivo experiments. The scanning electron microscopy results showed that the hybrid hydrogels had interconnected macropore structures that contained a COL reticular scaffold. The diameter of the macropore was 1.08-1.85 mm, which corresponds to the diameter of the denatured PVA column. The chondrocytes were then seeded in hydrogels to assess the cell viability and formation of the cartilage matrix. The in vitro results revealed excellent cellular biocompatibility. Osteochondral defects (8 mm in diameter and 8 mm in depth) were created in the femoral trochlear of goats, and the defects were implanted with cell-seeded hydrogels, cell-free hydrogels, or a blank control. The in vivo results showed that the COL-HA-PVA hydrogels effectively repaired cartilage defects, especially the conditions inoculated with chondrocyte in advance. This research suggests that the COL-HA-PVA hydrogels have promising application in cartilage repair.


Assuntos
Cartilagem/patologia , Hidrogéis/química , Álcool de Polivinil/química , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/química , Cartilagem/química , Cartilagem/metabolismo , Sobrevivência Celular , Condrócitos/metabolismo , Colágeno/química , Reagentes de Ligações Cruzadas/química , Elasticidade , Cabras , Técnicas In Vitro , Iridoides/química , Porosidade , Alicerces Teciduais , Viscosidade , Cicatrização
15.
Macromol Rapid Commun ; 41(13): e2000123, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32400926

RESUMO

Substituted naphthalimide (NI) moieties are highly versatile and newly recognized aggregation-induced emission (AIE) building blocks for many potentially useful smart molecules, polymers, and nanoparticles. However, the introduction of NI fluorophore into cross-linked polymeric networks to prepare AIE-active hydrogels still remains underdeveloped. Herein, a novel naphthalimide-based aggregation-induced emissive polymeric hydrogel is reported, followed by its proof-of-concept applications as fluorescence pattern switch and biomimetic actuator. The hydrogel, bearing semi-interpenetrating polymer networks, is synthesized starting from N-isopropylacrylamide, hydroxyethyl methacrylate, and a newly designed NI monomer (4-phenoxy-N-allyl-1,8-naphthalimide, PhAN). Rational molecular design for AIE-active PhAN monomer lies in modification of the NI core with rigid and bulky phenoxy group to break its planarity to produce desirable propeller-shaped molecular conformation. The as-prepared hydrogel is proved to be a aggregation-induced blue-light-emitting hydrogel. It also shows volume phase transition behavior and is endowed with thermally responsive synergistic emission and transmittance change, thus enabling simultaneous regulation of two optical properties merely by one single stimulus. These useful advantages further encourage fabrication of several proto-type fluorescence pattern switching and biomimetic actuating devices. This study may not only enlarge the list of fluorescent hydrogels but also serve as a novel smart optical platform for potential anticounterfeiting, sensing, displaying, or actuating applications.


Assuntos
Hidrogéis , Naftalimidas , Biomimética , Fluorescência , Polímeros
16.
J Orthop Sci ; 25(4): 708-714, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31607516

RESUMO

BACKGROUND: The use of 3D-printed scaffolds in repairing bone defects remains unexplored. We aimed to determine whether the duration of electrochemical deposition (ECD) affects the properties of hydroxyapatite (HA) coatings on 3D-printed titanium (TI) scaffolds as well as the corresponding phenotype of MC3T3-E1 cells seeded on these surfaces. METHODS: Five groups of HA-coated TI scaffolds were produced using different durations of ECD (0, 5, 10, 20, and 30 min) and examined under scanning electron microscopy (SEM). MC3T3-E1 cell adhesion to the HA-coated scaffolds and subsequent proliferation and viability were assessed using SEM, DAPI staining, EdU staining, and Alamar Blue assay, respectively. MC3T3-E1 cell expression of osteogenic genes was analyzed by fluorescence RT-PCR. RESULTS: On SEM, longer ECD durations resulted in more compact HA crystals of differing morphology coated onto the TI scaffolds. MC3T3-E1 cell adhesion differed among the five groups (p < 0.05), with the largest number of cells adhered to the scaffolds prepared with 30 min of ECD, followed by the group prepared with 20 min of ECD. However, the ECD duration of 20 min was associated with the highest cell viability and proliferation rate (both p < 0.05) as well as the highest mRNA expression levels of alkaline phosphatase, collagen I, osteocalcin and runt-related transcription factor 2 among the five groups (p < 0.05). CONCLUSIONS: In the fabrication of HA-coated 3D printed TI scaffolds, an ECD duration of 20 min resulted in scaffolds that best promoted MC3T3-E1 cell viability, proliferation and osteogenic gene expression.


Assuntos
Materiais Biocompatíveis , Adesão Celular/fisiologia , Durapatita , Osteogênese , Impressão Tridimensional , Alicerces Teciduais , Titânio , Células 3T3 , Animais , Camundongos , Fatores de Tempo
17.
J Clin Pediatr Dent ; 44(6): 436-441, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378465

RESUMO

BACKGROUND: Plasma cell granuloma (PCG) is a rare benign pseudotumorous proliferation of unclear etiology that is mainly situated in the lungs. Gingival PCG is an even more peculiar lesion that usually occurs in middle-aged or elderly individuals and clinically manifests as a solitary entity. CASE REPORT: A 15-year-old male with no underlying medical conditions presented with multiple gingival masses in the right maxilla, which were initially thought to be epulis. The lesions were resected completely and the excisional biopsies sent for histological examination. Immunohistochemical (IHC) stain revealed dense polyclonal plasma cell infiltration with positive expression of both kappa and lambda light chains, confirming a diagnosis of gingival PCG. Subsequently, the affected gingiva healed uneventfully, with no sign of recurrence over 2 years of follow-up. CONCLUSIONS: The present report depicts an extremely unusual case of gingival PCG occurring in a juvenile with multiple lesions, which is worth attention in clinical pediatric dentistry. Excisional-biopsy and histological investigations are imperative for a confirmative diagnosis and to exclude potential aggressive conditions. Complete resection of lesions seems to be a valid treatment, while long-term clinical follow-up is still needed.


Assuntos
Doenças da Gengiva , Granuloma de Células Plasmáticas , Adolescente , Idoso , Criança , Gengiva , Doenças da Gengiva/diagnóstico , Doenças da Gengiva/cirurgia , Granuloma de Células Plasmáticas/diagnóstico , Granuloma de Células Plasmáticas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
18.
Biomacromolecules ; 20(3): 1167-1177, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30689945

RESUMO

A biodegradable brush-type copolymer PHF- g-(PCL-PEG) based on a cleavable polyacetal backbone and biodegradable side chain modified with polyethylene glycol (PEG) was synthesized in this paper. This particular structure was directional to facilitate the formation of spherical or rod-shaped micelles. Flow cytometry showed that rod-shaped micelles displayed enhanced cellular uptake compared to spherical micelles. Rod-shaped micelles were selected to investigate their drug delivery abilities in detail. In vitro experiments verified the pH-triggered drug release of DOX-loaded micelles, and the release rate of doxorubicin (DOX) was 77% at pH 5.0 and 26% at pH 7.4. In drug-release kinetic analysis, a double-exponential model achieved the best fit. The copolymer appeared to be almost nontoxic, while the DOX-loaded micelles showed equivalent cytotoxicity compared to DOX at high concentration. The endocytosis of DOX-loaded micelles was two times that of DOX. Our findings suggest that the pH-sensitive brush type copolymer could be a possible carrier in drug delivery.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Concentração de Íons de Hidrogênio , Micelas , Polímeros/química , Células A549 , Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos , Humanos , Interações Hidrofóbicas e Hidrofílicas
19.
Biomacromolecules ; 20(2): 937-948, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30621397

RESUMO

To increase the cellular uptake and drug loading of cellulose nanocrystal (CNC)-based nanomedicines, folate/ cis-aconityl-doxorubicin@polyethylenimine@CNC (FA/CAD@PEI@CNC) nanomedicines were built up by the building blocks of folate (FA), cis-aconityl-doxorubicin (CAD), polyethylenimine (PEI), and CNCs via the robust layer-by-layer (LbL) assembly technique. The drug loading content (DLC) of FA/CAD@PEI@CNC hybrids was 11.3 wt %, which was almost 20-fold higher than that of the CNC-based nano-prodrug we reported previously. FA/CAD@PEI@CNC nanomedicines showed lysosomal pH-controlled drug release profiles over 24 h. In detail, the cumulative drug release was over 95% at pH 5.5, while the cumulative drug release was only 17% at pH 7.4. In vitro, FA/CAD@PEI@CNC hybrid nanomedicines had a higher (9.7-fold) mean fluorescent intensity (MFI) than that of DOX·HCl, with enhanced cytotoxicity and decreased IC50 against MCF-7. Thus, FA/CAD@PEI@CNC hybrid nanomedicines displayed efficient targetability and enhanced cellular uptake. In addition, FA/CAD@PEI@CNC nanomedicine could deliver more DOX to the nucleus than the control group, due to the ß-carboxylic acid catalyzed breakage of the pH-labile cis-aconityl amide linkages in CAD. These results indicated that FA/CAD@PEI@CNC nanomedicines achieved lysosomal pH-controlled drug release into the nucleus and showed great potential to be high-performance nanomedicines to improve the delivery efficiency and therapy efficacy. This study for CNC-based nanomedicines provided important insights into the bioapplication of CNCs modified by LbL assembly.


Assuntos
Núcleo Celular/metabolismo , Celulose/química , Preparações de Ação Retardada/química , Ácido Fólico/química , Lisossomos/química , Nanopartículas/química , Linhagem Celular Tumoral , Celulose/análogos & derivados , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Nanomedicina/métodos , Polietilenoimina/análogos & derivados , Polietilenoimina/química , Pró-Fármacos/química
20.
Macromol Rapid Commun ; 40(4): e1800648, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30485580

RESUMO

As one of the most important smart materials, fluorescent hydrogel actuators can produce both color and shape changes under external stimuli. In the present work, an effective approach to develop a novel fluorescent hydrogel actuator with pH and thermo dual responsiveness is proposed. Through incorporating pH-responsive perylene tetracarboxylic acid (PTCA), which is a typical fluorescent moiety with aggregation-caused quenching (ACQ) effect, into an anisotropic poly(N-isopropylacrylamide)-polyacrylamide (PNIPAm-PAAm) structure, the obtained hydrogel exhibits stable thermoresponsive shape deformation and switchable fluorescence performance upon a pH trigger. Therefore, fluorescence-quenching-based and actuation-based information can be revealed when exposed to UV light and immersed into warm water, respectively. Moreover, the thermoresponsive actuating behavior can be applied to further hide the fluorescence-quenching-based images. The present work may provide new insights into the design and preparation of novel stimuli-responsive hydrogel actuators.


Assuntos
Corantes Fluorescentes/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Temperatura , Fluorescência , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Propriedades de Superfície
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