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1.
Small ; 18(3): e2104623, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34837464

RESUMEN

Fused-ring electron donors boost the efficiency of organic solar cells (OSCs), but they suffer from high cost and low yield for their large synthetic complexity (SC > 30%). Herein, the authors develop a series of simple non-fused-ring electron donors, PF1 and PF2, which alternately consist of furan-3-carboxylate and 2,2'-bithiophene. Note that PF1 and PF2 present very small SC of 9.7% for their inexpensive raw materials, facile synthesis, and high synthetic yield. Compared to their all-thiophene-backbone counterpart PT-E, two new polymers feature larger conjugated plane, resulting in higher hole mobility for them, especially a value up to ≈10-4 cm2 V-1 ·s for PF2 with longer alkyl side chain. Meanwhile, PF1 and PF2 exhibit larger dielectric constant and deeper electronic energy level versus PT-E. Benefiting from the better physicochemical properties, the efficiencies of PF1- and PF2-based devices are improved by ≈16.7% and ≈71.3% relative to that PT-E-based devices, respectively. Furthermore, the optimized PF2-based devices with introducing PC71 BM as the third component deliver a higher efficiency of 12.40%. The work not only indicates that furan-3-carboxylate is a simple yet efficient building block for constructing non-fused-ring polymers but also provides a promising electron donor PF2 for the low-cost production of OSCs.


Asunto(s)
Energía Solar , Electrones , Polímeros/química , Luz Solar , Tiofenos/química
2.
Bull Environ Contam Toxicol ; 99(2): 270-275, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28500355

RESUMEN

Direct head-space solid-phase microextraction (HS-SPME) of phenols in water is usually difficult due to its polarity and solubility in aqueous matrix. Herein we report the fabrication of metal-organic framework MOF-177 coated stainless steel fiber for the HS-SPME of phenols (2-methylolphenol, 4-methylolphenol, 2,4-dimethylolphenol, 2,4-dichlorphenol, and 3-methyl-4-chlorophenol) in environmental water samples prior to the gas chromatography-mass spectrometry detection. Several parameters affecting the extraction efficiency were optimized in the experiment, including extraction temperature and time, the pH value and salt addition. The results indicated that the coated fiber gave low detection limits (0.015-0.043 µg L-1) and good repeatability with the RSD ranging from 2.8% to 5.5% for phenols. The recoveries are between 84.5%-98.6% with the spiked level of 10 µg L-1 for the real water samples. The established method may afford a kind of potential enrichment material and a reference method for the analysis of methylphenols in water samples.


Asunto(s)
Fenoles/análisis , Microextracción en Fase Sólida/instrumentación , Contaminantes Químicos del Agua/análisis , Clorofenoles/análisis , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Microextracción en Fase Sólida/métodos , Acero Inoxidable/química , Temperatura
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 715-22, 2017 Mar.
Artículo en Zh, Inglés | MEDLINE | ID: mdl-30148550

RESUMEN

We report tandem polymer light emitting devices by using the PEDOT∶PSS/ZnO/PEIE charge generation layer (CGL) and investigate the influences of the conductance and thickness of PEDOT∶PSS layer on the properties of the devices. The results indicate that the conductance and thickness of PEDOT∶PSS layer have marginal impact on the J-V characteristics of the devices, while significant influences of device efficiency upon utilization of different PEDOT∶PSS specimens mainly come from their different strengths on exciton quenching. Luminance efficiency of TOLEDs with the PEDOT∶PSS thickness of 60 nm in CGL is better than TOLEDs with the PEDOT∶PSS thickness of 30 nm in CGL, the reason is that PEDOT∶PSS thickness of 60 nm the surface topography is more even . Luminance efficiency and driving voltage of the tandem devices match the sum of the luminance efficiency and driving voltage of the component light-emitting units, respectively, indicating that charges generated in the CGL can be injected efficiently into the adjacent light-emitting units. Incorporation of a V2O5 layer into the CGL structure only slightly affects the J-V and LE-I characteristics of the tandem devices, suggesting that the utilization of the PEDOT∶PSS/ZnO/PEIE CGL enables the simplification of the CGL structure without compromising device performance. The luminescence spectra of TOLEDs obviously involves two light emitting unit of spectrum, which shows that two light emitting unit in TOLEDs is normal work. Measurements on the capacitance-voltage characteristics of the CGL-based devices confirm that under negative bias (ITO anode) charges are accumulated and displaced in the CGL, which is totally in line with the full operation of light emitting units in the tandem devices. PEDOT∶PSS/ZnO/PEIE layer is evidenced the effective CGL. On this basis, for the first time we report tandem polymer light emitting devices containing three SY-PPV light-emitting units,which show the mixture of luminance efficiency and external quantum efficiency of 21.7 cd·A-1 and 6.95%, similar to the total luminance efficiency and external quantum efficiency of constituent LEUs. At 5 000 cd·m-2, the luminance efficiency and external quantum efficiency of the tandem devices are 20.5 cd·A-1 and 6.6%. Thus, the increase in the number of light emitting units leads to almost no performance losses, implying the robustness of the PEDOT∶PSS/ZnO/PEIE CGL. Tandem polymer light emitting devices containing three SY-PPV light-emitting units of the luminescent spectra is close to the light emitting unit. Further efforts on the optimization of hole injection layer in the CGL to minimize exciton quenching are underlying to promote the luminance efficiency of tandem polymer light emitting devices.


Asunto(s)
Luminiscencia , Polímeros , Electrodos
4.
Acta Crystallogr C ; 69(Pt 4): 360-2, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23579706

RESUMEN

In the title compound, {[Zn(C8H4O5)(C12H10N2)]·0.5C12H10N2}n or {[Zn(HO-BDC)(bpe)]·0.5bpe}n [HO-H2BDC is 5-hydroxyisophthalic acid and bpe is 1,2-bis(pyridin-4-yl)ethene], the asymmetric unit contains a Zn(II) atom, one HO-BDC ligand, one coordinated bpe ligand and half a noncoordinating bpe molecule with crystallographic inversion symmetry. Each Zn(II) centre is four-coordinated by two O atoms from two distinct HO-BDC ligands and two N atoms from two different bpe ligands in a ZnO2N2 coordination environment. The three-dimensional topology of the title compound corresponds to a fourfold interpenetrating diamondoid coordination polymer network, with the uncoordinated bpe ligands located in the cavities, hydrogen bonded to the main network via the hydroxy group of the HO-H2BDC ligand.


Asunto(s)
Compuestos Organometálicos/química , Polímeros/química , Zinc/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Ligandos , Modelos Moleculares
5.
Artículo en Zh | MEDLINE | ID: mdl-24812845

RESUMEN

The gene-coding mature apyrase protein from Aedes albopictus was amplified by RT-PCR and cloned in frame with the a-factor secretion signal peptide into Pichia pastoris secreting expression vector pGAPZalpha-A resulting in the pGAPZa-A-apyrase. After being linearized by Bln I restriction enzyme, the recombinant pGAPZalpha-A-apyrase was trans-formed into Pichia pastoris GS115 by electroporation. Recombinant strains pGAPZalpha-A-apyrase/GS115 were screened on YPDS plates containing Zeocin and identified by PCR. The recombinant protein of apyrase (M(r) 60000) has been expressed in the supernatant of Pichia pastoris.


Asunto(s)
Aedes/enzimología , Apirasa/metabolismo , Proteínas de Insectos/metabolismo , Pichia/metabolismo , Animales , Proteínas Recombinantes/metabolismo , Saliva/enzimología
6.
Kaohsiung J Med Sci ; 37(6): 513-519, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33501725

RESUMEN

Osteoporosis (OP) behaves in different manners in different parts of the skeleton. This study aims to investigate the effects of curcumin on bone mass of the mandibular and femur from ovariectomized OP rats and to validate whether enhancer of zeste homolog 2 (EZH2)/Wnt/ß-Catenin pathway is involved in this process. Curcumin was administered intragastrically into ovariectomized rats for 12 weeks. The bone parameters and the morphology of the trabecular bone of the left mandible and left femur were assessed by micro-computed tomography assay. Morphological changes of the left mandible and left femur were evaluated by hematoxylin and eosin staining. The mRNA levels of EZH2, ß-Catenin, and Runx2 in the right mandible and right femur were examined by quantitative real-time polymerase chain reaction. Immunohistochemistry was performed to assess EZH2 expression. Both the mandible and femur exhibited OP-like changes in ovariectomized rats, while the mandible bone resorption was less than the femur bone resorption. Curcumin intragastric administration improved bone microstructure and promoted bone formation in the mandible and femur. Curcumin inhibited EZH2 mRNA level and induced that of ß-Catenin and Runx2 in the mandible and femur. Collectively, curcumin exerts protective effects against OP, possibly by regulating the EZH2/Wnt/ß-Catenin pathway.


Asunto(s)
Curcumina/farmacología , Proteína Potenciadora del Homólogo Zeste 2/biosíntesis , Fémur/metabolismo , Mandíbula/metabolismo , Osteoporosis/metabolismo , Proteínas Wnt/biosíntesis , beta Catenina/biosíntesis , Animales , Densidad Ósea/efectos de los fármacos , Femenino , Fémur/efectos de los fármacos , Mandíbula/efectos de los fármacos , Osteogénesis , Ovariectomía , Ratas , Ratas Sprague-Dawley , Vía de Señalización Wnt/fisiología , Microtomografía por Rayos X
7.
Small ; 6(5): 695-9, 2010 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-20025081

RESUMEN

Using ultrathin alumina membranes (UTAMs) as evaporation or etching masks large-scale ordered arrays of surface nanostructures can be synthesized on substrates. However, it is a challenge for this technique to synthesize quantum-sized surface structures. Here an innovative approach to prepare UTAMs with regularly arrayed pores in the quantum size range is reported. This new approach is based on a well-controlled pore-opening process and a modulated anodization process. Using UTAMs with quantum-sized pores for the surface patterning process, ordered arrays of quantum dots are synthesized on silicon substrates. This is the first time in realizing large-scale regularly arrayed surface structures in the quantum size range using the UTAM technique, which is an important breakthrough in the field of surface nanopatterning.


Asunto(s)
Óxido de Aluminio/química , Membranas Artificiales , Nanoestructuras/química , Puntos Cuánticos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Nanoestructuras/ultraestructura
8.
Anal Biochem ; 398(2): 191-7, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-19944059

RESUMEN

Here we report a simple, biomolecular-friendly protocol for the fabrication of a hydroxyapatite nanowires array (HANWA) biosensor of spatial positioning, large surface area, and abundant adsorbing sites and its application to cyanide sensing. The fabrication of HANWA is performed by template-assisted electrodeposition. The well-aligned hydroxyapatite nanoarray is composed of vertical nanowires with a diameter of approximately 200 nm and an average length of 1 microm. The electrochemical biosensor for the determination of cyanide through its inhibitory effect on horseradish peroxidase (HRP) encapsulated by chitosan (CHIT) on the platform of HANWA is demonstrated. The current organic-inorganic hybrid nanostructure provides excellent enzyme-substrate contact with enzyme activity well maintained. The densely distributed HANWA with large surface area and abundant adsorbing sites can provide a favorable electrochemical interface for the construction of electrochemical biosensor. A sensitive detection limit of 0.6 ng ml(-1) was obtained for cyanide. The proposed CHIT-HRP/HANWA biosensor has the advantages of spatial resolution, high sensitivity, rapid regeneration, and fast response associated with individual nanowires. It broadens the possible applications of chemosensors and biosensors, and it offers an alternative method for toxic substance determination. The new device holds great promise for environmental and food industrial monitoring of toxins.


Asunto(s)
Técnicas Biosensibles/instrumentación , Cianuros/análisis , Durapatita/química , Nanocables/química , Materiales Biocompatibles/química , Técnicas Biosensibles/métodos , Quitosano/química , Cianuros/farmacología , Conductividad Eléctrica , Electroquímica , Transporte de Electrón , Galvanoplastia , Inhibidores Enzimáticos/análisis , Inhibidores Enzimáticos/farmacología , Peroxidasa de Rábano Silvestre/antagonistas & inhibidores , Peroxidasa de Rábano Silvestre/química , Peroxidasa de Rábano Silvestre/metabolismo , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Permeabilidad
9.
ACS Appl Mater Interfaces ; 12(45): 50713-50720, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33112614

RESUMEN

We present a well-designed, low-cost, and simple synthetic approach to realizing the hybrid composites of Ag nanoparticle-decorated bacterial nanocellulose (denoted as Ag-NPs@BNC) as a three-dimensional (3D) flexible surface-enhanced Raman scattering (SERS) substrate with ultrahigh SERS sensitivity, excellent signal reproducibility, and stability. The homogeneous Ag-NPs with high density were in situ grown on the networked BNC fibers by the controlled silver mirror reaction and volume shrinkage treatment, which created uniformly distributed SERS "hot spots" in the 3D networked hybrid substrate. Attributed to these unique 3D hot spots, the as-presented Ag-NPs@BNC substrates exhibited ultrahigh sensitivity and good spectral reproducibility. Moreover, the hydrophilic BNC exhibits good permeability and adsorption performances, which could capture the target molecules in the highly active hot spot areas to further improve the SERS sensitivity. As a result, not only dye molecules (rhodamine 6G) but also toxic organic pollutants such as 2-naphthalenethiol and thiram have been detected using the hybrid substrates as SERS substrates, with sensitivities of 1.6 × 10-8 and 3.8 × 10-9 M, respectively. The good linear response of the intensity and the logarithmic concentration revealed promising applications in the rapid and quantitative detection of toxic organic pollutants. Besides, this self-supported Ag-NPs@BNC substrate demonstrated good stability and flexibility for varied detection conditions. Therefore, the 3D networked, flexible, ultrasensitive, and stable Ag-NPs@BNC substrate shows potential as a versatile SERS substrate in the rapid identification of various organic molecules.


Asunto(s)
Bacterias/química , Celulosa/química , Nanopartículas/química , Plata/química , Adsorción , Colorantes Fluorescentes/análisis , Naftalenos/análisis , Tamaño de la Partícula , Rodaminas/análisis , Espectrometría Raman , Compuestos de Sulfhidrilo/análisis , Propiedades de Superficie , Tiram/análisis
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(1): 76-80, 2019 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-30854824

RESUMEN

OBJECTIVE: We aim to examine teenagers with varying vertical facial skeletal types with near-normal occlusion. We further aim to identify and study mandibular morphology and dentition characteristics to establish normal ranges and variations for future clinical reference. METHODS: According to the results of the case studies, 42 adolescents with near-normal occlusion were divided into three groups, namely, low- (7 cases), average- (23 cases) and high-angle (12 cases) groups. We used Invivo 5 software for Digital Imaging and Communications in Medicine (DICOM) data to calculate the cant of occlusal plane, axis corner of L6, ∠L1/MP, ∠L6/MP, Balkwill angle and Bonwill triangle of each group. RESULTS: Markedly, the finding shows that the cant of occlusal plane and axis corner of L6 in the low-angle group were smaller than those of the other two groups. In the average-angle group, ∠L1/MP was larger than that of the high-angle group. Lastly, in the high-angle group, ∠L6/MP was smaller than those of the two other groups. On the one hand, these differences were considered statistically significant (P<0.05). On the other hand, other measurements show that these differences were considered statistically non-significant (P>0.05). CONCLUSIONS: In the low-angle group, the parallelisation of the occlusal plane tends to be more obvious compared with the two other groups. In the coronal section of the low-angle group, the axis of the mandibular first molar is up-right, whereas it is distally tilted in the sagittal section of the high-angle group. Furthermore, a number of differences are noted in the adult groups. Factors, such as aging and development in the craniofacial region, lead to changes in functional occlusion.


Asunto(s)
Cefalometría , Oclusión Dental , Dentición , Adolescente , Humanos , Mandíbula , Diente
11.
Shanghai Kou Qiang Yi Xue ; 28(5): 529-535, 2019 Oct.
Artículo en Zh | MEDLINE | ID: mdl-32274487

RESUMEN

PURPOSE:To investigate the effects of adenoid hypertrophy and maxillary sinus mucosal thickening on dentofacial development. METHODS:The selected subjects were divided into 4 groups according to the inclusion criteria: group A (adenoid hypertrophy with maxillary sinus mucosal thickening), group B (adenoid hypertrophy without maxillary sinus mucosal thickening), group C (normal adenoid with maxillary sinus mucosal thickening), and group D (normal adenoid without maxillary sinus mucosal thickening). There were 20 subjects in each group, aging from 12 to 14 years old. The volume of maxillary sinus was measured by Mimics software. The adenoid, dental arch width, basal bone width and palatal height were measured by Dolphin software and dentofacial measurements were performed in the lateral cephalograms derived from cone-beam CT (CBCT). The data were analyzed with SPSS 24.0 software package. RESULTS: There was no significant difference in dentofacial measurements between group B and group D or group C and group D,except for ANB angle (P<0.05). Compared with group D, SNB, ANB, Wits appraisal, NA-APo, MP-HP, N-Me, S-Go/N-Me, N-ANS (perp HP), sum of three angles, Ar-Go of group A were significantly different (P<0.05). Neither left nor right maxillary sinus bony volume had significant difference between group B and D or group C and D. CONCLUSIONS: Both adenoid hypertrophy and maxillary sinus mucosal thickening have impact on dentofacial development. Moderate or more severe adenoid hypertrophy with maxillary sinus mucosal thickening has greater impact on dentofacial development over adenoid hypertrophy or maxillary sinus mucosal thickening alone.


Asunto(s)
Tonsila Faríngea , Seno Maxilar , Adolescente , Niño , Tomografía Computarizada de Haz Cónico , Humanos , Hipertrofia , Maxilar
12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 33(10): 898-905, 2008 Oct.
Artículo en Zh | MEDLINE | ID: mdl-19001731

RESUMEN

OBJECTIVE: To determine the effective rule of protraction in different directions,strains, and shifts of maxillary bone,and to supply the scientific data for treatment of the maxilla in patients with cleft lip and palate. METHODS: " Based on the establishment of 3-dimensional finite element model of maxilla with cleft lip and palate,ANSYS 10.0 software was used to simulate protraction,and then we analyzed the change of maxillary stress and shift in the same force of traction in different directions. RESULTS: With 500 g per lateral protraction and the protraction angle from 20 degree to 45 degree,the maxillary shifted upward, forward, and outward, and the shape of maxillary plate bow showed internal shrinkage. There was a close relation between the internal shrinkage and the direction of protraction. The smaller the angle between the direction of protraction and the functional occlusion plane,the larger the internal shrinkage of tooth bow. The larger the angle between the direction of protraction and the functional occlusion plane,the smaller the internal shrinkage of tooth bow. CONCLUSION: With protraction,the maxilla grows upward, forward, and outward, and the maxillary palate shinks internally. There is a close relation between the direction of protraction and the range of internal shrinkage.


Asunto(s)
Labio Leporino/terapia , Fisura del Paladar/terapia , Aparatos de Tracción Extraoral , Análisis de Elementos Finitos , Maxilar/fisiología , Fenómenos Biomecánicos , Humanos , Imagenología Tridimensional , Maloclusión/terapia , Retrognatismo/terapia
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(5): 786-90, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18007071

RESUMEN

OBJECTIVE: To explore a faster and more precise method to establish a 3-dimensional (3 D) finite element model of maxillary in human complete unilateral cleft lip and palate. METHODS: The surface of the model was created using Materialists Interactive Medical Image Control System (Mimics) software to deal with Dicom standard files obtained by scanning the cranium of the patient with multi-slice helical CT. The 3D finite element model for complete unilateral cleft lip and plate in maxillary was established by Ansys software. RESULTS: A 3D finite element model of maxillary in human complete unilateral cleft lip and palate was constructed with 27,405 units and 26,876 nodes. CONCLUSION: The combination of Mimics software, Geomagic studio software, Ansys software, and spiral CT is able to create a 3D finite element counter model, which provides a faster and more valid method to study complete unilateral cleft lip and palate.


Asunto(s)
Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Niño , Femenino , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional/métodos , Programas Informáticos , Tomografía Computarizada Espiral/métodos
14.
Shanghai Kou Qiang Yi Xue ; 26(1): 1-6, 2017 Feb.
Artículo en Zh | MEDLINE | ID: mdl-28474057

RESUMEN

PURPOSE: To establish cranio-maxillary complex finite element models (FEMs) in cleft lip and palate (CLP) patients with miniplate and tooth-borne anchorage, and to investigate the biomechanical effects on maxillary protraction. METHODS: The protracting process was simulated on FEMs established from a male patient's cone beam CT (CBCT) data to analyze the displacement and stress from different appliances. RESULTS: Four FEMs of unilateral cleft lip and palate (UCLP) or bilateral cleft lip and palate (BCLP) patients' cranio-maxillary complex with MA and TA were established. The maxillary arch on both sides of the cleft moved towards the cleft side during protraction, which was more obvious in the miniplate anchorage three-dimensional finite element models(FEM-MA) than the tooth-borne anchorage three-dimensional finite element models (FEM-TA).The amount of forward, downward displacement of the inferior orbital rim, paranasal area and middle maxilla point in the FEM-MA was larger than that in the FEM-TA, while the amount of forward displacement of premaxilla and upper canine in the FEM-TA was larger than that in the FEM-MA. The FEM-MA exhibited an orthopedic effect with more favorable stress distribution on the middle maxilla point while the FEM-TA showed a dentoalveolar effect with prominent stress distribution on the upper canine point. In addition, the FEM-MA showed a larger stress distribution area and sutural stress value than did the FEM-TA. The UCLP models showed an asymmetric pattern in stress distribution and displacement, which was larger on the cleft side than that on the non-cleft side. The amount of displacement of premaxilla in the BCLP models was smaller than that in the UCLP models. CONCLUSIONS: The established models have high geomagic and biomechanical similarities. It would be more advantageous to obtain more aesthetic outcomes and better stability using the miniplate anchorage.


Asunto(s)
Labio Leporino/terapia , Análisis de Elementos Finitos , Animales , Fisura del Paladar , Perros , Masculino , Maxilar , Modelos Biológicos , Cráneo
15.
Mater Sci Eng C Mater Biol Appl ; 72: 134-142, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28024569

RESUMEN

For the clinical application of bone tissue engineering with the combination of biomaterials and mesenchymal stem cells (MSCs), bone scaffolds should possess excellent biocompatibility and osteoinductivity to accelerate the repair of bone defects. Herein, strontium hydroxyapatite [SrHAP, Ca10-xSrx(PO4)6(OH)2]/chitosan (CS) nanohybrid scaffolds were fabricated by a freeze-drying method. The SrHAP nanocrystals with the different x values of 0, 1, 5 and 10 are abbreviated to HAP, Sr1HAP, Sr5HAP and Sr10HAP, respectively. With increasing x values from 0 to 10, the crystal cell volumes and axial lengths of SrHAP become gradually large because of the greater ion radius of Sr2+ than Ca2+, while the crystal sizes of SrHAP decrease from 70.4nm to 46.7nm. The SrHAP/CS nanohybrid scaffolds exhibits three-dimensional (3D) interconnected macropores with pore sizes of 100-400µm, and the SrHAP nanocrystals are uniformly dispersed within the scaffolds. In vitro cell experiments reveal that all the HAP/CS, Sr1HAP/CS, Sr5HAP/CS and Sr10HAP/CS nanohybrid scaffolds possess excellent cytocompatibility with the favorable adhesion, spreading and proliferation of human bone marrow mesenchymal stem cells (hBMSCs). The Sr5HAP nanocrystals in the scaffolds do not affect the adhesion, spreading of hBMSCs, but they contribute remarkably to cell proliferation and osteogenic differentiation. As compared with the HAP/CS nanohybrid scaffold, the released Sr2+ ions from the SrHAP/CS nanohybrid scaffolds enhance alkaline phosphatase (ALP) activity, extracellular matrix (ECM) mineralization and osteogenic-related COL-1 and ALP expression levels. Especially, the Sr5HAP/CS nanohybrid scaffolds exhibit the best osteoinductivity among four groups because of the synergetic effect between Ca2+ and Sr2+ ions. Hence, the Sr5HAP/CS nanohybrid scaffolds with excellent cytocompatibility and osteogenic property have promising application for bone tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Hidroxiapatitas/química , Nanoestructuras/química , Estroncio/química , Ingeniería de Tejidos , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Materiales Biocompatibles/farmacología , Células de la Médula Ósea/citología , Huesos/citología , Huesos/metabolismo , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Microscopía Electrónica de Rastreo , Osteogénesis/efectos de los fármacos , Tamaño de la Partícula , Andamios del Tejido/química
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(3): 411-3, 2006 Jun.
Artículo en Zh | MEDLINE | ID: mdl-16859136

RESUMEN

OBJECTIVE: To evaluate the therapeutic effects of MBT straight wire on extraction case of Class II division I. METHODS: Thirty-six class II division I malocclusion patients were treated with MBT straight wire by extracting 4 bicuspid premolars or 2 maxillary bicuspid premolars. The X-ray cephalograms were analyzed before and after the treatment of MBT straight wire. RESULTS: After the treatment, the overjet was reduced by 6.04 mm (P < 0.01); U1-NA was reduced by 15.43 degrees (P <0.01); and U1-NA (mm) was reduced by 4.71 mm (P <0.01). ANB was significantly reduced (P < 0.05). CONCLUSION: MBT straight wire not only shortens the operation but also shows superior effect for Class II division I malocclusion cases.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Alambres para Ortodoncia , Ortodoncia Correctiva/instrumentación , Adolescente , Niño , Femenino , Humanos , Masculino , Diseño de Aparato Ortodóncico , Ortodoncia Correctiva/métodos
17.
J Mech Behav Biomed Mater ; 61: 345-359, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27107263

RESUMEN

Implant-associated infection is a common postoperative complication and remains a serious problem in orthopedic surgery. This work describes the synthesis of silver nanoparticle-doped hydroxyapatite coatings with oriented block arrays (AgNP-BHAC). The resulting nanostructure was investigated using scanning electron microscopy, energy-dispersive spectrometry, transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. AgNP-BHAC exhibited excellent antimicrobial activity toward gram-negative Escherichia coli and gram-positive Staphylococcus aureus owing to the antibacterial effects of the silver nanoparticles. Human bone marrow stromal cells (hBMSC) culture revealed that the AgNP-BHAC exhibited better biocompatibility, and permitted improved cell proliferation, attachment, and osteoinductivity than uncoated Ti-6Al-4V titanium alloy, the favored material for biomedical applications. In summary, this study presents a convenient and effective method for the incorporation of silver into HA coatings with block morphology. This method can be utilized to modify a variety of metallic implant surfaces to improve their antimicrobial effects and reduce potential long-term cytotoxicity.


Asunto(s)
Antibacterianos/química , Materiales Biocompatibles Revestidos , Durapatita/química , Nanopartículas del Metal/química , Plata/química , Células Cultivadas , Humanos , Microscopía Electrónica de Rastreo , Staphylococcus aureus , Células del Estroma/citología , Titanio , Difracción de Rayos X
18.
Mater Sci Eng C Mater Biol Appl ; 67: 395-408, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27287136

RESUMEN

Hydroxyapatite (HA) crystals exhibit rod-like shape with c-axis orientation and plate-like shape with a(b)-axis orientation in vertebrate bones and tooth enamel surfaces, respectively. Herein, we report the synthesis of HA coatings with the oriented nanorod arrays (RHACs) and HA coatings with oriented nanoplate arrays (PHACs) by using bioglass coatings as sacrificial templates. After soaking in simulated body fluid (SBF) at 120°C, the bioglass coatings are hydrothermally converted into the HA coatings via a dissolution-precipitation reaction. If the Ca/P ratios in SBF are 2.50 and 1.25, the HA crystals on the coatings are oriented nanorod arrays and oriented nanoplate arrays, respectively. Moreover, the bioglass coatings are treated with SBF at 37°C, plate-like HA coatings with a low crystallinity (SHACs) are prepared. As compared with the Ti6Al4V and SHACs, the human bone marrow stromal cells (hBMSCs) on the RHACs and PHACs have better cell adhesion, spreading, proliferation and osteogenic differentiation because of their moderately hydrophilic surfaces and similar chemical composition, morphology and crystal orientation to human hard tissues. Notably, the morphologies of HA crystals have no obvious effects on cytocompatibility and osteogenic differentiation. Hence, the HA coatings with oriented nanoplate arrays or oriented nanorod arrays have a great potential for orthopedic applications.


Asunto(s)
Células de la Médula Ósea/metabolismo , Durapatita/química , Membranas Artificiales , Nanotubos/química , Osteogénesis , Aleaciones , Células de la Médula Ósea/citología , Adhesión Celular , Células Cultivadas , Humanos , Nanotubos/ultraestructura , Células del Estroma/citología , Células del Estroma/metabolismo , Titanio/química
19.
Shanghai Kou Qiang Yi Xue ; 22(1): 35-40, 2013 Feb.
Artículo en Zh | MEDLINE | ID: mdl-23552779

RESUMEN

PURPOSE: To explore an effective method to construct and validate a finite element model of the unilateral cleft lip and palate(UCLP) craniomaxillary complex with sutures, which could be applied in further three-dimensional finite element analysis (FEA). METHODS: One male patient aged 9 with left complete lip and palate cleft was selected and CT scan was taken at 0.75mm intervals on the skull. The CT data was saved in Dicom format, which was, afterwards, imported into Software Mimics 10.0 to generate a three-dimensional anatomic model. Then Software Geomagic Studio 12.0 was used to match, smoothen and transfer the anatomic model into a CAD model with NURBS patches. Then, 12 circum-maxillary sutures were integrated into the CAD model by Solidworks (2011 version). Finally meshing by E-feature Biomedical Modeler was done and a three-dimensional finite element model with sutures was obtained. A maxillary protraction force (500 g per side, 20° downward and forward from the occlusal plane) was applied. Displacement and stress distribution of some important craniofacial structures were measured and compared with the results of related researches in the literature. RESULTS: A three-dimensional finite element model of UCLP craniomaxillary complex with 12 sutures was established from the CT scan data. This simulation model consisted of 206 753 individual elements with 260 662 nodes, which was a more precise simulation and a better representation of human craniomaxillary complex than the formerly available FEA models. By comparison, this model was proved to be valid. CONCLUSIONS: It is an effective way to establish the three-dimensional finite element model of UCLP cranio-maxillary complex with sutures from CT images with the help of the following softwares: Mimics 10.0, Geomagic Studio 12.0, Solidworks and E-feature Biomedical Modeler.


Asunto(s)
Labio Leporino , Imagenología Tridimensional , Niño , Fisura del Paladar , Análisis de Elementos Finitos , Humanos , Masculino , Maxilar , Suturas
20.
Bioresour Technol ; 101(10): 3665-71, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20100654

RESUMEN

High-melting-temperature poly(ethylene terephthalate) (PET) was successfully introduced into wood plastic composites through a two-step reactive extrusion technology. Wood flour was added into pre-prepared PET/high density polyethylene (HDPE) microfibrillar blends (MFBs) in the second extrusion at the temperature for processing HDPE. Addition of 25% in situ formed PET microfibers obviously increased the mechanical properties of HDPE, and more significant enhancement by the in situ formed recycled PET microfibers was observed for the recycled HDPE. Adding 2% E-GMA improved the compatibility between matrix and microfibers in MFBs, resulting further enhanced mechanical properties. The subsequent addition of 40% wood flour did not influence the size and morphology of PET microfibers, and improved the comprehensive mechanical properties of MFBs. The wood flour increased the crystallinity level of HDPE in the compatibilized MFB in which PET phase did not crystallize. The storage modulus of MFB was greatly improved by wood flour.


Asunto(s)
Plásticos , Tereftalatos Polietilenos/química , Polietilenos/química , Madera , Cristalización , Resistencia a la Tracción
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