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1.
Small ; : e2401397, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898735

RESUMEN

Pyroptosis, an inflammatory cell death, plays a pivotal role in activating inflammatory response, reversing immunosuppression and enhancing anti-tumor immunity. However, challenges remain regarding how to induce pyroptosis efficiently and precisely in tumor cells to amplify anti-tumor immunotherapy. Herein, a pH-responsive polydopamine (PDA) nanocluster, perfluorocarbon (PFC)@octo-arginine (R8)-1-Hexadecylamine (He)-porphyrin (Por)@PDA-gambogic acid (GA)-cRGD (R-P@PDA-GC), is rationally design to augment phototherapy-induced pyroptosis and boost anti-tumor immunity through a two-input programmed cascade therapy. Briefly, oxygen doner PFC is encapsulated within R8 linked photosensitizer Por and He micelles as the core, followed by incorporation of GA and cRGD peptides modified PDA shell, yielding the ultimate R-P@PDA-GC nanoplatforms (NPs). The pH-responsive NPs effectively alleviate hypoxia by delivering oxygen via PFC and mitigate heat resistance in tumor cells through GA. Upon two-input programmed irradiation, R-P@PDA-GC NPs significantly enhance reactive oxygen species production within tumor cells, triggering pyroptosis via the Caspase-1/GSDMD pathway and releasing numerous inflammatory factors into the TME. This leads to the maturation of dendritic cells, robust infiltration of cytotoxic CD8+ T and NK cells, and diminution of immune suppressor Treg cells, thereby amplifying anti-tumor immunity.

2.
Langmuir ; 40(23): 12239-12249, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38819103

RESUMEN

The high gravimetric (58.74 kJ/g) and volumetric (137.45 kJ/cm3) heat values loaded in boron (B) offer significant potential for application in solid propellants and explosives. However, the high melting (2076 °C) and boiling (3927 °C) points of boron powder and the low melting point (450 °C) of oxidation products affect the energy performance and application of boron. Fluorine-containing polymers have high oxidation potential and excellent mechanical properties and can produce expectant gaseous products through the combustion reaction with boron oxide, but research examining the interaction between purified boron powder and fluoropolymers and the optimal selection of the fluoropolymer remains scarce. Herein, the binding energy between typical fluoropolymers [Viton, polyvinylidene fluoride, poly(vinylidene fluoride-co-chlorotrifluoroethylene), and vinylidene fluoride] and boron was calculated via molecular dynamics simulations, which shows that Viton is an appropriate candidate for coating boron powder. In the experiment, The Bw@Viton core-shell composites were prepared using Viton as the coating layer, and boron powder was pre-purified with acetonitrile. Its structure, thermal properties, ignition, and combustion characteristics were then characterized. The results revealed successful removal of the oxide layer, and the hydrophobicity was significantly improved after Viton coating. Purification and coating synergistically enhance the energy release of boron powder, and the composites demonstrated excellent thermal, ignition, and combustion performances. In particular, the heat of oxidation and heat of combustion were increased by 26.6 and 32.7%, respectively. The ignition delay time was reduced by 53.2% compared to raw boron. A prospective reaction mechanism between boron and Viton is thus proposed.

3.
J Prosthet Dent ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38627178

RESUMEN

Precise implant placement is key to ensuring the success of dental implant surgery. Implant robotic systems have been increasingly adopted for clinical procedures because of their accuracy. Maxillary sinus floor elevation with the Disk-up Sinus Reamer (DSR) may be an effective solution for inadequate posterior maxillary bone height. This clinical treatment combined with an autonomous implant robot with DSR for maxillary sinus floor elevation with simultaneous dental implant surgery may be suitable for clinical practice.

4.
J Prosthet Dent ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38918156

RESUMEN

Yakebot, the first autonomous robotic dental implant system, provides a 1-stop solution for implant design, robot operation, real-time navigation, and precision analysis. This report describes the composition, principles, and implant operation procedures of the Yakebot dental implant robotic system in a patient for whom the robotic workflow procedure was used to place implants in the edentulous maxilla. The results showed that this workflow was more precise and predictable than traditional methods.

5.
Opt Express ; 31(16): 25598-25612, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710442

RESUMEN

To meet the demand of flexible access for high-precision synchronization frequency, we demonstrate multi-node stable radio frequency (RF) dissemination over a long-distance optical fiber. Stable radio frequency signals can be extracted at any node along the optical fiber, not just at the endpoint. The differential mixing structure (DMS) is employed to avoid the frequency harmonic leakage and enhance the precision. The phase-locked loop (PLL) provides frequency reference for the DMS while improving the signal to noise ratio (SNR) of dissemination signal. We measure the frequency instability of multi-node stable frequency dissemination system (MFDS) at different locations along the 2,000 km optical fiber. The measured short-term instability with average time of 1 s are 1.90 × 10-14 @ 500 km, 2.81 × 10-14 @ 1,000 km, 3.46 × 10-14 @ 1,500 km, and 3.84 × 10-14 @ 2,000 km respectively. The long-term instability with average time of 10,000 s are basically the same at any position of the optical fiber, which is about (6.24 ± 0.05) × 10-17. The resulting instability is sufficient for the propagation of precision active hydrogen masers.

6.
Med Sci Monit ; 29: e938566, 2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36932638

RESUMEN

BACKGROUND This study evaluated the clinical efficacy of polylactic acid (PLA) membranes in guiding bone regeneration in anterior maxillary implants. MATERIAL AND METHODS Forty-eight participants with maxillary anterior tooth loss requiring implantation with guided bone regeneration were recruited and randomly divided into 2 groups (n=24): the PLA membrane (experimental) and the Bio-Gide membrane (control) group. Wound healing was observed at 1 week and 1 month postoperatively. Cone beam CT was performed immediately and at 6 and 36 months postoperatively. Soft-tissue parameters were measured at 18 and 36 months postoperatively. Implant stability quotient (ISQ) and patient satisfaction were separately evaluated at 6 and 18 months after the operation. The independent sample t test and chi-square test were preformed to analyze quantitative and descriptive statistics, respectively. RESULTS No implants were lost and there were no statistically significant differences in ISQ between the 2 groups. The labial bone plates in the experimental group exhibited a non-significantly greater extent of absorption than did the control group at 6 and 18 months postoperatively. Soft-tissue parameters did not reveal inferior results for the experimental group. Patients in both groups were satisfied. CONCLUSIONS PLA membranes are comparable to Bio-Gide in terms of the effectiveness and safety and can be used as a barrier membrane to guide bone regeneration in clinical practice.


Asunto(s)
Regeneración Ósea , Implantes Dentales , Humanos , Poliésteres/farmacología , Resultado del Tratamiento , Cicatrización de Heridas
7.
J Prosthet Dent ; 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37442750

RESUMEN

Autogenous dental root placement is an available approach for horizontal alveolar ridge augmentation in patients with severe bony defects. However, in previous reports, bone augmentation has been done before the implant placement. This clinical report describes the use of dentin grafting for alveolar ridge augmentation and simultaneous implant placement in the maxillary left central incisor region with a severe horizontal bone defect. Under strict adherence to the recommended indications, dentin grafting and simultaneous implantation could be clinically feasible protocols.

8.
Molecules ; 28(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37049973

RESUMEN

Boron powder is a kind of metal fuel with high gravimetric and volumetric calorific values, which has been widely used in military fields such as solid propellants, high-energy explosives, and pyrotechnics. However, the easily formed liquid oxide layer can adhere to the surface of boron powder and react with the hydroxyl (-OH) group of hydroxyl-terminated polybutadiene (HTPB) binder to form a gel layer that is detrimental to propellant processing and restricts the complete oxidation of boron powder. Therefore, to improve the combustion efficiency of boron powder, the ignition and combustion mechanisms of boron powder have been studied, and surface coating modification strategies have been developed by researchers worldwide, aiming to optimize the surface properties, improve the reaction activity, and promote the energy release of boron powder. In this review, recent studies on the ignition and combustion mechanisms of boron powder are discussed. Moreover, the reported boron powder coating materials are classified according to the chemical structure and reaction mechanism. Additionally, the mechanisms and characteristics of different coating materials are summarized, and the mechanism diagrams of fluoride and metal oxide are provided. Furthermore, promising directions for modification methods and the potential application prospects of boron powder are also proposed.

9.
J Prosthet Dent ; 122(4): 383-388, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30982624

RESUMEN

STATEMENT OF PROBLEM: High rates of veneering chipping are a common prosthodontic complication of restorations with a titanium framework. A new bio high-performance polymer (BioHPP) based on polyetheretherketone (PEEK) has been introduced for denture superstructures. Clinical reports suggest that BioHPP could be used as an alternative framework material to support complete-arch restorations. However, peer-reviewed information is lacking regarding the performance of BioHPP as a framework material for implant-supported screw-retained fixed dental prostheses (FDPs) veneered with composite resin. PURPOSE: The purpose of this in vitro study was to evaluate and compare the bond strength of modified PEEK (BioHHP) and titanium with a veneering composite resin and compare the marginal fit and fracture resistance of implant-supported screw-retained FDPs fabricated by using computer-aided design and computer-aided manufacturing (CAD-CAM) frameworks veneered with composite resin. MATERIAL AND METHODS: A composite resin was bonded to 2 framework materials (n=20/group): pure titanium (Ti) and BioHPP (Bi). The shear bond strength (SBS) was determined after 24-hour wet storage. Furthermore, 20 3-unit CAD-CAM BioHPP and titanium frameworks were fabricated (n=10/group). The marginal fit between frameworks and abutments was evaluated by scanning electron microscopy by using the single-screw test. After thermocycling and mastication simulation, the fracture resistance of FDPs veneered with the composite resin was examined. The independent sample t test was used to evaluate differences (α=.05). RESULTS: Significantly higher shear bond strengths were obtained in group Bi (31.1 ±3.5 MPa) than in group Ti (20.5 ±1.8 MPa). The mean marginal gap width was 19 ±4 µm in group Bi and 16 ±6 µm in group Ti. Statistical tests showed no significant differences (P>.05). After loading, veneering chipping was observed at a load of 1960 ±233 N in group Ti. Although the BioHPP frameworks fractured at 1518 ±134 N, no chipping occurred. CONCLUSIONS: The bond strength of BioHPP with the composite resin was greater than that of titanium. CAD-CAM BioHPP frameworks exhibit good marginal fit and fracture resistance. BioHPP may be a suitable alternative to metal as a framework to be veneered with composite resin.


Asunto(s)
Prótesis Dental de Soporte Implantado , Titanio , Resinas Compuestas , Diseño Asistido por Computadora , Materiales Dentales , Porcelana Dental , Ensayo de Materiales , Polímeros , Circonio
10.
Shanghai Kou Qiang Yi Xue ; 33(1): 64-70, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38583027

RESUMEN

PURPOSE: To analyze the bone remodeling around the implant 10 years after disk-up sinus reamer(DSR)-based internal sinus floor elevation with implantation and to investigate the influence of different factors on implant retention. METHODS: The clinical and imaging data of patients undergoing DSR-based sinus floor elevation with simultaneous implantation were collected from the Department of Dental Implantology, Affiliated Hospital of Qingdao University from January 2008 to December 2011. Panoramic film and CBCT were used to measure the changes of bone mass around implant in different periods. Kaplan-Meier and Log-rank tests were used to analyze the effects of different factors on implant retention with SPSS 26.0 software package. RESULTS: The study included 98 patients with a total of 128 implants. During the follow-up of 0-168 months, 7 implants failed, and the remaining formed good osseointegration and functioned, with a 10-year cumulative retention rate of 94.53%. The height of bone formation was (0.29±0.15) mm at the top and (2.74±0.66) mm in the sinus of 75 implant sites with complete imaging data obtained ten years after surgery. Kaplan-Meier and Log-rank tests showed that 8 factors including initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis had significant effects on implant retention. CONCLUSIONS: The DSR-based internal sinus floor elevation with implantation is a reliable and stable bone augmentation operation for vertical bone defect in maxillary posterior region, with a 10-year cumulative retention rate of no less than 94%. Initial bone height, elevated bone height, mucosal perforation, implant length, implant torsion, diabetes, smoking and periodontitis are the important factors affecting the long-term retention rate of implants.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Elevación del Piso del Seno Maxilar , Humanos , Implantación Dental Endoósea/métodos , Diabetes Mellitus/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Periodontitis , Resultado del Tratamiento
11.
Clin Implant Dent Relat Res ; 26(2): 309-316, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37728030

RESUMEN

AIMS: To compare the accuracy of the Yakebot dental implant robotic system with that of fully guided static computer-assisted implant surgery (CAIS) template in edentulous implantation. MATERIALS AND METHODS: Thirteen patients with edentulous were recruited and divided into two groups: the Yake robotic system group (experimental) (n = 5) and the CAIS group (control) (n = 8). Postoperative cone-beam computed tomography (CBCT) was performed immediately, and the 3-dimensional positions of implants were obtained and compared with that in the preoperative design. The comparison showed platform, apical, depth, and angular deviations. A value of p < 0.05 was considered statistically significant. RESULTS: A total of 84 implants (36 in the robotic group and 48 in the CAIS group) were placed. The mean deviation at the implant platform, apex, depth, and angle in the CAIS group was 1.37 ± 0.72 mm, 1.28 ± 0.68 mm, 0.88 ± 0.47 mm, and 3.47 ± 2.02°, respectively. However, the mean deviation at the implant platform, apex, depth, and angle in the robotic group was 0.65 ± 0.25 mm, 0.65 ± 0.22 mm, 0.49 ± 0.24 mm, and 1.43 ± 1.18°, respectively. Significant differences in the four types of deviation (p < 0.05) between the two groups were observed. CONCLUSION: The accuracy of robotic system in edentulous implant placement was superior to that of the CAIS template, suggesting that robotic system is more accurate, safe, and flexible, can be considered a promising treatment in clinical practice.


Asunto(s)
Implantes Dentales , Arcada Edéntula , Boca Edéntula , Procedimientos Quirúrgicos Robotizados , Cirugía Asistida por Computador , Humanos , Implantación Dental Endoósea/métodos , Arcada Edéntula/cirugía , Cirugía Asistida por Computador/métodos , Boca Edéntula/diagnóstico por imagen , Boca Edéntula/cirugía , Tomografía Computarizada de Haz Cónico , Diseño Asistido por Computadora , Computadores , Imagenología Tridimensional
12.
Int J Periodontics Restorative Dent ; (7): s295-s306, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36856732

RESUMEN

Osteoporosis is an increasingly prevalent disease. The development of an osteoporosis-like experimental animal model is of great importance for the study of peri-implant osteogenesis in osteoporosis. The present authors aimed to establish a rapid modeling method of osteoporotic rabbits for implant-bone analysis and validate whether the models can affect the implant osseointegration. The present study included 29 female New Zealand rabbits (age: 5 to 6 months). Two rabbits were lost during anesthetization. Of the remaining 27 rabbits, 18 received an ovariectomy, with 9 receiving dexamethasone injections for 8 weeks (OVX+D group) and 9 receiving equivalent-volume saline injections (OVX group). As a control group, the remaining 9 rabbits were sham-operated and received an equivalent volume of normal saline (SHAM group). Then, serum biochemical markers of bone metabolism were detected and densitometric measurements were performed. Implants were then placed in the tibias of each rabbit. Bone samples (including implants) were obtained after 4, 8, and 12 weeks of healing and were subjected to histologic and histomorphometric analyses. The results showed that the OVX+D group experienced a 32% reduction in bone mineral density (BMD) from baseline. The BMD of the OVX+D group was significantly lower than that of the SHAM and OVX groups. Moreover, alkaline phosphatase (ALP) blood concentrations of in the OVX+D group were increased significantly. The osteoporotic rabbits exhibited marked decreases in osseointegration, characterized by slowed bone formation and decreased bone-to-implant contact (BIC). The combination of an ovariectomy and dexamethasone injections could experimentally induce osteoporosis in rabbits in the short term, which can be used as an appropriate animal model to study the osseointegration of implants under osteoporosis.


Asunto(s)
Implantes Dentales , Osteoporosis , Femenino , Conejos , Animales , Densidad Ósea , Oseointegración , Modelos Teóricos , Dexametasona/farmacología
13.
Int J Oral Maxillofac Implants ; 38(2): 374-380, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37083918

RESUMEN

Purpose: To evaluate the long-term functional and esthetic effects of immediate implantation combined with guided bone regeneration in patients with labial bone plate defects. Materials and Methods: A total of 46 implants were immediately placed into anterior maxillary fresh sockets with buccal bone defects. Jumping space and the outer side of buccal defects were densely filled with hydroxyapatite bioceramics and covered with biomembrane. CBCT was performed immediately after surgery (T1), 6 months later (T2), and after 5 years (T3). Radiographs were taken at 1 month after surgery (RT1), definitive crown delivery (RT2), and once a year after prosthetic loading (RT3 to RT7) for 5 years. Pink esthetic score (PES) was evaluated at the time of definitive crown delivery (PT1) and at follow-up visits 1, 3, and 5 years (PT2 to PT4) after crown fixation. Results: No implants were lost during the observational period. The labial bone was radiographically reconstructed to acceptable volumes, with an average 2.86-mm horizontal bone and 2.2-mm vertical bone. Significant marginal bone loss occurred within 1 year after delivery of the definitive prosthesis. PES scores did not reveal inferior results at the 5-year follow-up. Conclusion: When other conditions are met for immediate implant placement, small labial plate defects (≤ 5 mm) will not affect the long-term esthetic effect.


Asunto(s)
Pérdida de Hueso Alveolar , Implantes Dentales de Diente Único , Implantes Dentales , Carga Inmediata del Implante Dental , Humanos , Estudios Retrospectivos , Carga Inmediata del Implante Dental/métodos , Resultado del Tratamiento , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/cirugía , Estética Dental , Alveolo Dental/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Estudios de Seguimiento
14.
Nanoscale Horiz ; 8(4): 422-440, 2023 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-36852666

RESUMEN

Wound healing is a complex and dynamic process, in which the pH value plays an important role in reflecting the wound status. Wound dressings are materials that are able to accelerate the healing process. Among the multifunctional advanced wound dressings developed in recent years, pH-responsive wound dressings, especially hydrogels, show great potential owing to their unique properties of adjusting their functions according to the wound conditions, thereby allowing the wound to heal in a regulated manner. However, a comprehensive review of pH-responsive wound dressings is lacking. This review summarizes the design strategies and advanced functions of pH-responsive hydrogel wound dressings, including their excellent antibacterial properties and significant pro-healing abilities. Other advanced pH-responsive materials, such as nanofibers, composite films, nanoparticle clusters, and microneedles, are also classified and discussed. Next, the pH-monitoring functions of pH-responsive wound dressings and the related pH indicators are summarized in detail. Finally, the achievements, challenges, and future development trends of pH-responsive wound dressings are discussed.


Asunto(s)
Vendajes , Cicatrización de Heridas , Antibacterianos/uso terapéutico , Concentración de Iones de Hidrógeno
15.
FEBS Open Bio ; 12(5): 1006-1016, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35032368

RESUMEN

Autophagy can affect the invasion and metastasis of carcinoma. Our previous study has shown that invasion and epithelial-mesenchymal transition in salivary adenoid cystic carcinoma (SACC) can be promoted by the metabolic reprogramming of free fatty acids (FFAs). However, the effect of FFA metabolism on autophagy in SACC remains unknown. In this study, we showed that overexpression of paired related homeobox 1 (PRRX1) reduced the number of autophagosomes and decreased the expression of LC3 and Beclin-1 in SACC patients and SACC-83 cells in vitro. Moreover, PRRX1-mediating FFA reprogramming triggered to autophagy via regulating acetyl-CoA carboxylase 1 (ACC1), leading to invasion and migration in SACC.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias de las Glándulas Salivales , Acetil-CoA Carboxilasa/genética , Autofagia , Carcinoma Adenoide Quístico/genética , Carcinoma Adenoide Quístico/metabolismo , Carcinoma Adenoide Quístico/patología , Línea Celular Tumoral , Ácidos Grasos , Genes Homeobox , Proteínas de Homeodominio/genética , Humanos , Neoplasias de las Glándulas Salivales/genética , Neoplasias de las Glándulas Salivales/metabolismo , Neoplasias de las Glándulas Salivales/patología
16.
Front Bioeng Biotechnol ; 10: 804201, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35360406

RESUMEN

With the development of nanotechnology, nanomaterials have been used in dental fields over the past years. Among them, graphene and its derivatives have attracted great attentions, owing to their excellent physicochemical property, morphology, biocompatibility, multi-differentiation activity, and antimicrobial activity. In our review, we summarized the recent progress about their applications on the dentistry. The synthesis methods, structures, and properties of graphene-based materials are discussed. Then, the dental applications of graphene-based materials are emphatically collected and described. Finally, the challenges and outlooks of graphene-based nanomaterials on the dental applications are discussed in this paper, aiming at inspiring more excellent studies.

17.
Stem Cells Int ; 2022: 1395299, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36017130

RESUMEN

Scutellarin is known as a safe, effective, and low-cost traditional Chinese medicine and has a variety of biological activities. Studies reported that the scutellarin loaded on ultradeformable nanoliposome scutellarin EDTMP (S-UNL-E) could promote osteoblast differentiation and bone formation in vitro. However, its effect on promoting osteogenesis in vivo is still unclear. In this study, pharmacology network and transcriptome sequencing were used to screen the potential targets and pathways of scutellarin in treating osteoporosis. The female Sprague-Dawley (SD) rats were operated on with bilateral oophorectomy and femoral defect to establish an osteoporosis model and then treated separately with bone dust, single scutellarin, 40 mg/kg ultradeformable nanoliposome scutellarin (S-UNL), and the optimal concentration of 40 mg/kg S-UNL-E for a total of 56 d to detect the parameters of trabecular bones. And qRT-PCR and western blot were performed to determine the expression of prostaglandin-endoperoxide synthase 2 (PTGS2), alkaline phosphatase (ALP), transcription factor 4 (TCF4), and ß-catenin. Results of microscopic computed tomography (Micro-CT) of trabecular bones showed that single scutellarin, S-UNL, and S-UNL-E all promoted the bone formation of osteoporotic rats, in which S-UNL-E manifested the most remarkable therapeutic effect. And it is found that 40 mg/kg of S-UNL-E increased the expression of PTGS2, ALP, TCF4, and ß-catenin, which indicated that S-UNL-E stimulated the secretion of ALP in bone defect areas to promote bone healing, and increased PTGS2 expression thereby enhancing the transcription and translation of key gene ß-catenin and TCF4 in the Wnt/ß-catenin signaling pathway to treat osteoporotic rats.

18.
Int J Mol Med ; 48(4)2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34414453

RESUMEN

The present study aimed to investigate the effect of ß­receptor blocker propranolol on early osseointegration of pure titanium implants and the underlying molecular regulatory mechanisms. An implant osseointegration model using the tibial metaphysis of New Zealand rabbits was established. The rabbits were divided into control and low­, medium­ and high­dose propranolol groups. The formation of implant osseointegration was detected by X­ray scanning. Mesenchymal stem cells (MSCs) and osteoblasts (OBs) were isolated and cultured in vitro, isoproterenol was supplemented to simulate sympathetic action and propranolol was subsequently administrated. The effect of propranolol on cell proliferation and osteogenic differentiation were assessed by EdU, flow cytometry, alizarin red staining and alkaline phosphatase (ALP) detection. The expression levels of bone morphogenetic protein (BMP)2, RUNX family transcription factor (RunX)2, collagen (COL)­1, osteocalcin (OCN) and ß2­adrenergic receptor (AR) were detected by immunofluorescence, reverse transcription­quantitative PCR and western blot assay. Propranolol effectively promoted implant osseointegration in vivo, facilitated proliferation of OBs, inhibited proliferation of MSCs and enhanced osteogenic differentiation of OBs and MSCs. The calcium content and ALP activity of cells treated with propranolol were markedly higher than in the control group. Propranolol also elevated mRNA and protein expression levels of BMP2, RunX2, COL­1 and OCN in tissue and cells, and decreased the expression of ß2­AR. The present study demonstrated that the ß­receptor blocker propranolol promoted osteogenic differentiation of OBs and MSCs and enhanced implant osseointegration. The present study provided a novel insight into the application and regulatory mechanisms of propranolol.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Oseointegración/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Propranolol/farmacología , Animales , Proteína Morfogenética Ósea 2/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteocalcina/efectos de los fármacos , Osteocalcina/metabolismo , Conejos , Receptores Adrenérgicos beta 2/metabolismo , Titanio/farmacología
19.
Shanghai Kou Qiang Yi Xue ; 30(5): 477-480, 2021 Oct.
Artículo en Zh | MEDLINE | ID: mdl-34888598

RESUMEN

PURPOSE: To investigate the effect of paired related homeobox1 (PRRX1) on autophagy of salivary adenoidcystic carcinoma (SACC) cells. METHODS: PRRX1-overexpressed lentiviral vectors and their negative control lentiviral vectors were used to transfect SACC cells. The transfection effect was detected by Western blot. Autophagosome was observed under transmission electron microscopy(TEM). The level of autophagy markers (LC3-II/Beclin1) was detected by immunofluorescence and Western blot. Statistical analysis was performed with SPSS 17.0 software package. RESULTS: PRRX1 protein level increased, autophagosome number decreased, and autophagy marker level decreased in the PRRX1 overexpressed group, compared to the control (P<0.05). CONCLUSIONS: PRRX1 inhibits the autophagy of SACC cells.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias de las Glándulas Salivales , Autofagia , Beclina-1 , Carcinoma Adenoide Quístico/genética , Línea Celular Tumoral , Proteínas de Homeodominio , Humanos , Neoplasias de las Glándulas Salivales/genética
20.
Dalton Trans ; 50(47): 17766-17773, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34813635

RESUMEN

The surface functionalization of graphene oxide (GO) is always attractive in improving certain properties of the polymer. In this study, 3-aminopropyltriethoxysilane (APTES) and 3-mercaptopropyl-trimethoxysilane (SPTES) have been used to make silane functionalized graphene oxides (SiGOs). The APTES-grafted GO (NH-SiGO), SPTES-grafted GO (SH-SiGO) and pure GO have been separately introduced into the nitrocellulose (NC) matrix. The morphology, thermal properties and energetic properties of the prepared nanocomposites (NH-SiGO and SH-SiGO) were investigated comprehensively. It is shown that the presence of GO and SiGOs have different influences on the thermal reactivity of NC with various contents, and NH-SiGO with 0.5 wt% content showed better catalytic performance on the thermal decomposition of NC than others and showed prominently higher efficiency in improving its heat of combustion. Adding 0.5 wt% of NH-SiGO to NC may decrease its decomposition temperature from 202.1 °C to 196.6 °C, and the residue was decreased from 10.61 wt% to 3.95 wt%, respectively. One isoconversional kinetic method was exploited to determine the kinetic parameters of NC and its nanocomposites. It was found that NH-SiGO had a strong catalytic action on the thermal decomposition of NC-based nanocomposites for which the activation energy and the pre-exponential factor were considerably lowered, while SH-SiGO exhibited an inverse effect. The heat of combustion from NC/GO/0.5, NC/NH-SiGO/0.5 and NC/SH-SiGO/0.5 were determined as 11 249.5, 11 675.1 and 11 491.5 J g-1, respectively, which are higher than that of the pure NC (10 908.4 J g-1). From the combustion process of NC/NH-SiGO/0.5, it was shown that the nanocomposite was combusted completely.

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