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1.
Int J Nanomedicine ; 16: 1509-1523, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33658781

RESUMEN

Purpose: The study was intended to create a uniform zirconia layer even on the surface of complex structures via atomic layer deposition (ALD). The impact of crystalline zirconia deposited by ALD on bacterial adhesion and osteoblast viability was assessed via surface treatment of dental implants. Methods: Amorphous zirconia was deposited using an atomic layer deposition reactor (Atomic Classic, CN1, Hwaseong, Korea) on titanium discs. Heating the samples at 400°C resulted in crystallization. Samples were divided into three groups: the control group, the group carrying amorphous ALD-zirconia (Z group), and the heat-treated group following zirconia ALD deposition (ZH group).The surface of each sample was analyzed, followed by the assessment of adhesion of Streptococcus mutans and Porphyromonas gingivalis, and viability and differentiation of MC3T3-E1 cells. Results: The adhesion of S. mutans and P. gingivalis was significantly reduced in the Z and ZH groups compared with the control group (P < 0.05). The viability of MC3T3-E1 cells was significantly increased in the ZH group compared with the control group (P < 0.001), while no significant differences were observed in the Z group (P > 0.05). Differentiation of MC3T3-E1 cells showed a marginally significant increase in the ZH group compared with the control group (P < 0.1), while no significant differences were found in the Z group (P > 0.1). Conclusion: Compared with the pure titanium group, the groups that were coated with zirconia via ALD showed a decreased adhesion of S. mutans during the early stages of biofilm formation and P. gingivalis adhesion inducing peri-implantitis, and an increase in MC3T3-E1 cell viability and differentiation. The findings indicate the possibility of treating the implant surface to reduce peri-implantitis and improve osseointegration.


Asunto(s)
Adhesión Bacteriana , Osteoblastos/citología , Titanio/farmacología , Circonio/química , Animales , Adhesión Bacteriana/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Ratones , Microscopía de Fuerza Atómica , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/ultraestructura , Espectroscopía de Fotoelectrones , Espectrometría por Rayos X , Propiedades de Superficie , Difracción de Rayos X
2.
ACS Appl Mater Interfaces ; 13(3): 3521-3527, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33440931

RESUMEN

Small-molecule impurities, such as N-nitrosodimethylamine (NDMA), have infiltrated the generic drug industry, leading to recalls in commonly prescribed blood pressure and stomach drugs in over 43 countries since 2018 and directly affecting tens of millions of patients. One promising strategy to remove small-molecule impurities like NDMA from drug molecules is by size exclusion, in which the contaminant is removed by selective adsorption onto a (micro)porous material due to its smaller size. However, current solution-phase size-exclusion separations are primarily limited by the throughput-selectivity trade-off. Here, we report a bioinspired solution to conquer these critical challenges by leveraging the assembly of atomically precise building blocks into hierarchically porous structures. We introduce a bottom-up approach to form micropores, mesopores, and macroscopic superstructures simultaneously using functionalized oxozirconium clusters as building blocks. Further, we leverage recent advances in photopolymerization to design macroscopic flow structures to mitigate backpressure. Based on these multiscale design principles, we engineer simple, inexpensive devices that are able to separate NDMA from contaminated drugs. Beyond this urgent model system, we expect this design strategy to open up hitherto unexplored avenues of nanomaterial superstructure fabrication for a range of size-exclusion purification strategies.


Asunto(s)
Dimetilnitrosamina/aislamiento & purificación , Compuestos Organometálicos/química , Circonio/química , Adsorción , Contaminación de Medicamentos , Extracción Líquido-Líquido , Modelos Moleculares , Porosidad
3.
Life Sci ; 271: 119070, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33465388

RESUMEN

AIMS: In vivo biodistribution of radio labeled ZrO2 nanoparticles is addressed for better imaging, therapy and diagnosis. Nanoparticles are synthesized by microwave assisted sol-gel technique using Fe3O4 as a stabilizer. Antioxidant assay, hemolytic activity in human blood and biodistribution in rabbits was explored to study the therapeutical as well as in vivo targeted diagnostic applications of as synthesized nanoparticles. MAIN METHODS: Fe3O4 stabilized zirconia nanoparticles are synthesized using microwave assisted sol-gel method. Microwave (MW) powers are varied in the range of 100 to 1000 W. As synthesized nanoparticles are evaluated using different characterizations such as X-ray diffractometer, scanning electron microscope, Raman spectroscopy, impedance analyzer, Vickers micro hardness indenter, FTIR, and UV-Vis spectroscopy. In vitro activity of synthesized nanoparticles is checked in freshly extracted human blood serum. To study biodistribution of Fe3O4 stabilized zirconia nanoparticles in rabbit, technetium-99 m was used for labeling purpose. The labeling efficacy and stability of labeled nanoparticles are also measured with instant thin layer chromatography (ITLC) method. Intravenous injection of 99mTc-Fe3O4 stabilized zirconia nanoparticles (0.2 ml), containing 110 MBq of radioactivity, is performed to study the biodistribution; nanoparticles are injected into the ear vein of animal (rabbit). KEY FINDINGS: Zirconia (ZrO2) nanoparticles (NPs) are stabilized using Fe3O4 that were prepared by means of microwave assisted sol-gel method. Crystallite size (~20 nm) agrees well with the values required to stabilize tetragonal zirconia (t-ZrO2). Volume shrinkage results in high value of hardness (~1369). Dielectric constant values, compatible for biomedical application, are observed for tetragonally stabilized samples. Low value of hemolytic response is observed for Fe3O4 stabilized ZrO2 NPs. 99mTc radio labeled ZrO2 NPs proved to be potential candidate to study biodistribution. Biodistribution studies show stability of radiolabeled NPs in the original suspension as well as in blood serum. CT scan of rabbit is performed for several times to check the biodistribution of NPs with time and survival of rabbit. Results suggest that these NPs can also be used as targeted nanoparticles as well as variants of drug payload carrier. SIGNIFICANCE: Results signify that Fe3O4 stabilized ZrO2 nanoparticles synthesized by microwave assisted sol-gel method may be considered as "all-rounder" nanoplatform and are safe enough to be used in diagnostic as well as therapeutic purposes.


Asunto(s)
Compuestos Férricos/metabolismo , Depuradores de Radicales Libres/metabolismo , Microondas , Nanopartículas/metabolismo , Radioinmunodetección/métodos , Circonio/metabolismo , Animales , Compuestos Férricos/síntesis química , Humanos , Nanopartículas/química , Conejos , Tecnecio/metabolismo , Distribución Tisular/fisiología , Difracción de Rayos X/métodos , Circonio/química
4.
Anal Chem ; 93(4): 2090-2096, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33435685

RESUMEN

The sensitive detection of coronavirus is of vital importance for the prevention of its rapid spread. Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that causes severe diarrhea and death in neonatal piglets. In this work, a novel PCN-224-based electrochemiluminescence (ECL) system was constructed for PEDV detection with high sensitivity. We found that PCN-224 can be employed as an ECL reporter with a strong signal because of its zirconium-based organic porous frame nanomaterial with a large specific surface area and stable structure. TiO2 nanoparticles were used as an accelerator for the first time to promote the reduction of coreactant potassium peroxydisulfate on the cathode; thus, the initial ECL signal of PCN-224 was significantly amplified. In the presence of PEDV, the ECL signal decreased due to the block effect to electron transfer. As a result, the novel "signal off" biosensor achieved a sensitive detection of PEDV ranging from 1 pg/mL to 10 ng/mL, with a detection limit of 0.4 pg/mL (S/N = 3). Importantly, the PCN-224 nanomaterial enriched the ECL system in biological analysis, and the proposed strategy provided a new route for coronavirus detection.


Asunto(s)
Técnicas Electroquímicas/métodos , Estructuras Metalorgánicas/química , Porfirinas/química , Circonio/química , Técnicas Biosensibles , Luminiscencia , Nanopartículas del Metal/química , Microscopía Electrónica de Transmisión , Titanio/química
5.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445501

RESUMEN

This research paper is concentrated on the design of biologically compatible lead-free piezoelectric composites which may eventually replace traditional lead zirconium titanate (PZT) in micromechanical fluidics, the predominantly used ferroelectric material today. Thus, a lead-free barium-calcium zirconate titanate (BCZT) composite was synthesized, its crystalline structure and size, surface morphology, chemical, and piezoelectric properties were analyzed, together with the investigations done in variation of composite thin film thickness and its effect on the element properties. Four elements with different thicknesses of BCZT layers were fabricated and investigated in order to design a functional acoustophoresis micromechanical fluidic element, based on bulk acoustic generation for particle control technologies. Main methods used in this research were as follows: FTIR and XRD for evaluation of chemical and phase composition; SEM-for surface morphology; wettability measurements were used for surface free energy evaluation; a laser triangular sensing system-for evaluation of piezoelectric properties. XRD results allowed calculating the average crystallite size, which was 65.68 Å3 confirming the formation of BCZT nanoparticles. SEM micrographs results showed that BCZT thin films have some porosities on the surface with grain size ranging from 0.2 to 7.2 µm. Measurements of wettability showed that thin film surfaces are partially wetting and hydrophilic, with high degree of wettability and strong solid/liquid interactions for liquids. The critical surface tension was calculated in the range from 20.05 to 27.20 mN/m. Finally, investigations of piezoelectric properties showed significant results of lead-free piezoelectric composite, i.e., under 5 N force impulse thin films generated from 76 mV up to 782 mV voltages. Moreover, an experimental analysis showed that a designed lead-free BCZT element creates bulk acoustic waves and allows manipulating bio particles in this fluidic system.


Asunto(s)
Acústica/instrumentación , Materiales Biocompatibles/química , Cerámica/química , Circonio/química , Bario/química , Electroforesis/métodos , Diseño de Equipo , Glicerol/química , Plomo , Microscopía Electrónica de Rastreo , Aceite de Oliva/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
6.
Molecules ; 26(2)2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33419179

RESUMEN

A new conjugate of gallato zirconium (IV) phthalocyanine complexes (PcZrGallate) has been obtained from alkilamino-modified SiO2 nanocarriers (SiO2-(CH2)3-NH2NPs), which may potentially be used in photodynamic therapy of atherosclerosis. Its structure and morphology have been investigated. The photochemical properties of the composite material has been characterized. in saline environments when exposed to different light sources Reactive oxygen species (ROS) generation in DMSO suspension under near IR irradiation was evaluated. The PcZrGallate-SiO2 conjugate has been found to induce a cytotoxic effect on macrophages after IR irradiation, which did not correspond to ROS production. It was found that SiO2 as a carrier helps the photosensitizer to enter into the macrophages, a type of cells that play a key role in the development of atheroma. These properties of the novel conjugate may make it useful in the photodynamic therapy of coronary artery disease.


Asunto(s)
Complejos de Coordinación , Portadores de Fármacos , Indoles , Fotoquimioterapia , Fármacos Fotosensibilizantes , Placa Aterosclerótica , Dióxido de Silicio , Circonio , Animales , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Indoles/química , Indoles/farmacología , Ratones , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Células RAW 264.7 , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Circonio/química , Circonio/farmacología
7.
Food Chem ; 337: 127974, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920274

RESUMEN

Facile enrichment and determination of trace organophosphorus pesticides (OPPs) in foods has been a constantly pursuing goal in food safety field. Herein, Zr4+-immobilized covalent organic frameworks (Fe3O4@COF@Zr4+) have been first constructed and utilized as the powerful adsorbents for magnetic solid-phase extraction (MSPE) of OPPs. Owing to the π-π stacking interaction, hydrogen bonding and Zr4+-phosphate coordination reaction, the composites exhibited excellent selectivity and superior affinity to OPPs. Under optimized conditions, the proposed MSPE method coupled with GC-FPD showed good linearity (R2 ≥ 0.9990) and yielded low limits of detection (0.7-3.0 µg kg-1) for OPPs. Moreover, the developed method was successfully employed for the quantitation of OPPs in spiked vegetable samples and obtained satisfactory recoveries in the range of 87-121% with the relative standard deviations (RSDs) ≤ 8.9%. These results demonstrated that the prepared nanoparticles hold unique advantages for trace OPPs analysis in foodstuffs.


Asunto(s)
Estructuras Metalorgánicas/química , Organofosfatos/análisis , Plaguicidas/análisis , Extracción en Fase Sólida/métodos , Verduras/química , Compuestos de Anilina/química , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Hierro/química , Límite de Detección , Fenómenos Magnéticos , Nanocompuestos/química , Extracción en Fase Sólida/instrumentación , Circonio/química
8.
Chemosphere ; 263: 127938, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32829222

RESUMEN

The urgent need for eutrophication control motivated the development of many novel adsorbents for enhanced phosphate polishing removal. Among these, zirconium-based nanomaterial was regarded as an effective kind because of its ability to bind phosphate specifically via inner-sphere complexation. In this study, we proposed a new strategy to improve the efficiency of zirconium oxides (HZO) nanoparticles by immobilizing them onto a gel-type anion exchange resin covalently attached with ammonium groups, denoted as HZO@N201. A previously developed macro-porous polymeric nanocomposite HZO@D201 was used for comparison. The immobilized nanoparticles in HZO@N201 were well dispersed in the gel matrix, manifesting smaller particle size and richer surface hydroxyl groups in comparison to HZO@D201. As a result of the structural merits in collective, HZO@N201 not only exhibited superior phosphate adsorptive capacity and affinity towards phosphate to HZO@D201, but also facilitate phosphate diffusion, based on isotherm, pH and kinetic tests. Mechanistic study by XPS and 31P SS-NMR substantiated the selective phosphate adsorption pathway as the formation of inner-sphere complexes by HZO@N201, which exhibited enhanced reactivity than HZO@D201. Lastly, fixed-bed runs of HZO@N201 was conducted, achieving an effective treatable volume of 2000 BV, which was 600 BV more than HZO@D201. Additional adsorption-regeneration cycle confirmed its reusability and potential for practical application. We believe the gel-type polymeric host could facilitate the formation and dispersion of smaller sized nanoparticles, exposing more surface hydroxyl groups highly accessible to phosphate. The results of this paper offer insights to a new strategy for immobilization of functional nanoparticles aiming at enhanced adsorptive removal of phosphate.


Asunto(s)
Fosfatos/química , Poliestirenos/química , Contaminantes Químicos del Agua/química , Circonio/química , Adsorción , Resinas de Intercambio Aniónico/química , Concentración de Iones de Hidrógeno , Inmovilización , Nanocompuestos/química , Nanopartículas , Óxidos , Polímeros , Contaminantes Químicos del Agua/análisis
9.
Chemosphere ; 262: 128317, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33182083

RESUMEN

The development of industrialization and agricultural activities have carried various negative impacts to living organisms in recent decades and also, the frequent problem of inorganic pollution have been environmental anxiety to the community. Among these, Cr6+ and F- are priority poisonous pollutants from many industries. In this work, we present a low-cost synthesis procedure to obtain biocompatible zirconium incorporated chitosan-gelatin composite (CS-Zr-GEL) were fabricated and explored for the adsorptive removal of toxic Cr6+ and F- from water. The adsorption mechanism of toxic Cr6+ and F- was done by batch mode as a function of contact time, solution pH and co-existing ions. The obtained materials were extensively studied by several physico-chemical techniques to access their properties by X-ray diffraction (XRD), scanning electron microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analysis. Additionally, the fabricated adsorbent is highly dependent on solution pH. The kinetic and isotherm data were fitted using pseudo-second-order kinetic and Langmuir isotherm models. The maximum adsorption capacity for CS-Zr-GEL is 138.89 and 12.13 mg/g at 323K for Cr6+ and F- respectively. These findings demonstrate that the CS-Zr-GEL adsorbent represents a promising candidate that would have a practical influence on water/wastewater treatments.


Asunto(s)
Quitosano/química , Cromo/análisis , Fluoruros/análisis , Gelatina/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Circonio/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Aguas Residuales/química
10.
Int J Nanomedicine ; 15: 9891-9907, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33328732

RESUMEN

Purpose: The aim of this study was to investigate the effect of various mass fractions of 10-methacry-loyloxydecyl dihydrogen phosphate (MDP)-conditioned or unconditioned zirconia nano- or micro-particles with different initiator systems on the mechanical properties of nanohybrid resin composites. Methods: Both light-cured (L) and dual-cured (D) resin composites were prepared. When the mass fraction of the nano- or micro-zirconia fillers reached 55 wt%, resin composites were equipped with dual-cured initiator systems. We measured the three-point bending-strength, elastic modulus, Weibull modulus and translucency parameter of the nanohybrid resin composites containing various mass fractions of MDP-conditioned or unconditioned zirconia nano- or micro-particles (0%, 5 wt%, 10 wt%, 20 wt%, 30 wt% and 55 wt%). A Cell Counting Kit (CCK)-8 was used to test the cell cytotoxicity of the experimental resin composites. The zirconia nano- or micro-particles with MDP-conditioning or not were characterized by transmission electron microscopy (TEM), Fourier infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Results: Resin composites containing 5-20 wt% MDP-conditioned or unconditioned nano-zirconia fillers exhibited better three-point bending-strength than the control group without zirconia fillers. Nano- or micro-zirconia fillers decreased the translucence of the nanohybrid resin composites. According to the cytotoxicity classification, all of the nano- or micro-zirconia fillers containing experimental resin composites were considered to have no significant cell cytotoxicity. The FTIR spectra of the conditioned nano- or micro-fillers showed new absorption bands at 1719 cm-1 and 1637 cm-1, indicating the successful combination of MDP and zirconia particles. The XPS analysis measured Zr-O-P peak area on MDP-conditioned nano- and micro-zirconia fillers at 39.91% and 34.89%, respectively. Conclusion: Nano-zirconia filler improved the mechanical properties of nanohybrid resin composites, but cannot be the main filler to replace silica filler. The experimental dual-cured composites can be resin cements with better opacity effects and a low viscosity.


Asunto(s)
Fenómenos Mecánicos , Nanopartículas/química , Circonio/química , Resinas Compuestas/química , Módulo de Elasticidad , Ensayo de Materiales , Metacrilatos/química , Fosfatos/química , Dióxido de Silicio/química , Propiedades de Superficie
11.
Nat Protoc ; 15(11): 3579-3594, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33028982

RESUMEN

Efficient methods to functionalize proteins are essential for the development of many diagnostic and therapeutic compounds, such as fluorescent probes for immunohistochemistry, zirconium-89 radiolabeled mAbs (89Zr-mAbs) for positron emission tomography and antibody-drug conjugates (ADCs). This protocol describes a step-by-step procedure for the light-induced functionalization of proteins with compounds bearing the photochemically active aryl azide group. As an illustration of the potential utility of our approach, this protocol focuses on the synthesis of 89Zr-mAbs using photoactivatable derivatives of the metal ion binding chelate desferrioxamine B (DFO). The light-induced synthesis of 89Zr-mAbs is a unique, one-pot process involving simultaneous radiolabeling and protein conjugation. The photoradiochemical synthesis of purified 89Zr-mAbs, starting from unmodified proteins, [89Zr][Zr(C2O4)4]4- (89Zr-oxalate), and a photoactivatable DFO derivative, can be performed in <90 min. The method can be easily adapted to prepare other radiolabeled proteins, ADCs or fluorescently tagged proteins by using drug molecules or fluorophores functionalized with photoactive moieties.


Asunto(s)
Anticuerpos Monoclonales/química , Inmunoconjugados/química , Radioisótopos/química , Circonio/química , Técnicas de Química Sintética/instrumentación , Técnicas de Química Sintética/métodos , Diseño de Equipo , Luz , Modelos Moleculares
12.
J Vis Exp ; (162)2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32894264

RESUMEN

Localized surface plasmon resonance (LSPR) in plasmonic nanoparticles (NPs) can accelerate and control the selectivity of a variety of molecular transformations. This opens possibilities for the use of visible or near-IR light as a sustainable input to drive and control reactions when plasmonic nanoparticles supporting LSPR excitation in these ranges are employed as catalysts. Unfortunately, this is not the case for several catalytic metals such as palladium (Pd). One strategy to overcome this limitation is to employ bimetallic NPs containing plasmonic and catalytic metals. In this case, the LSPR excitation in the plasmonic metal can contribute to accelerate and control transformations driven by the catalytic component. The method reported herein focuses on the synthesis of bimetallic silver-palladium (Ag-Pd) NPs supported on ZrO2 (Ag-Pd/ZrO2) that acts as a plasmonic-catalytic system. The NPs were prepared by co-impregnation of corresponding metal precursors on the ZrO2 support followed by simultaneous reduction leading to the formation of bimetallic NPs directly on the ZrO2 support. The Ag-Pd/ZrO2 NPs were then used as plasmonic catalysts for the reduction of nitrobenzene under 425 nm illumination by LED lamps. Using gas chromatography (GC), the conversion and selectivity of the reduction reaction under the dark and light irradiation conditions can be monitored, demonstrating the enhanced catalytic performance and control over selectivity under LSPR excitation after alloying non-plasmonic Pd with plasmonic metal Ag. This technique can be adapted to a wide range of molecular transformations and NPs compositions, making it useful for the characterization of the plasmonic catalytic activity of different types of catalysis in terms of conversion and selectivity.


Asunto(s)
Aleaciones/química , Nanopartículas del Metal/química , Paladio/química , Plata/química , Aleaciones/síntesis química , Catálisis , Luz , Nitrobencenos/química , Oxidación-Reducción , Resonancia por Plasmón de Superficie , Circonio/química
13.
Int J Nanomedicine ; 15: 6137-6152, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32884268

RESUMEN

Background: Beyond clinical atherosclerosis imaging of vessel stenosis and plaque morphology, early detection of inflamed atherosclerotic lesions by molecular imaging could improve risk assessment and clinical management in high-risk patients. To identify inflamed atherosclerotic lesions by molecular imaging in vivo, we studied the specificity of our radiotracer based on maleylated (Mal) human serum albumin (HSA), which targets key features of unstable atherosclerotic lesions. Materials and Methods: Mal-HSA was radiolabeled with a positron-emitting metal ion, zirconium-89 (89Zr4+). The targeting potential of this probe was compared with unspecific 89Zr-HSA and 18F-FDG in an experimental model of atherosclerosis (Apoe-/- mice, n=22), and compared with wild-type (WT) mice (C57BL/6J, n=21) as controls. Results: PET/MRI, gamma counter measurements, and autoradiography showed the accumulation of 89Zr-Mal-HSA in the atherosclerotic lesions of Apoe-/- mice. The maximum standardized uptake values (SUVmax) for 89Zr-Mal-HSA at 16 and 20 weeks were 26% and 20% higher (P<0.05) in Apoe-/- mice than in control WT mice, whereas no difference in SUVmax was observed for 18F-FDG in the same animals. 89Zr-Mal-HSA uptake in the aorta, as evaluated by a gamma counter 48 h postinjection, was 32% higher (P<0.01) for Apoe-/- mice than in WT mice, and the aorta-to-blood ratio was 8-fold higher (P<0.001) for 89Zr-Mal-HSA compared with unspecific 89Zr-HSA. HSA-based probes were mainly distributed to the liver, spleen, kidneys, bone, and lymph nodes. The phosphor imaging autoradiography (PI-ARG) results corroborated the PET and gamma counter measurements, showing higher accumulation of 89Zr-Mal-HSA in the aortas of Apoe-/- mice than in WT mice (9.4±1.4 vs 0.8±0.3%; P<0.001). Conclusion: 89Zr radiolabeling of Mal-HSA probes resulted in detectable activity in atherosclerotic lesions in aortas of Apoe-/- mice, as demonstrated by quantitative in vivo PET/MRI. 89Zr-Mal-HSA appears to be a promising diagnostic tool for the early identification of macrophage-rich areas of inflammation in atherosclerosis.


Asunto(s)
Aterosclerosis/diagnóstico por imagen , Maleatos/química , Imagen Molecular/métodos , Radioisótopos , Albúmina Sérica Humana/química , Circonio , Animales , Aorta/diagnóstico por imagen , Aorta/patología , Aterosclerosis/patología , Autorradiografía , Modelos Animales de Enfermedad , Femenino , Fluorodesoxiglucosa F18 , Humanos , Marcaje Isotópico , Macrófagos/patología , Imagen por Resonancia Magnética , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/patología , Tomografía de Emisión de Positrones , Radioisótopos/química , Radioisótopos/farmacocinética , Radiofármacos/química , Distribución Tisular , Circonio/química , Circonio/farmacocinética
14.
Int J Nanomedicine ; 15: 5061-5072, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32764936

RESUMEN

Purpose: Zirconia is one of the most promising implant materials due to its favorable physical, mechanical and biological properties. However, until now, we know little about the mechanism of osseointegration on zirconia. The purpose of this study is to evaluate the effect of Syndecan (Sdc) on osteoblastic cell (MC3T3-E1) adhesion and proliferation onto zirconia materials. Materials and Methods: The mirror-polished disks 15 mm in diameter and 1.5 mm in thick of commercial pure titanium (CpTi), 3mol% yttria-stabilized tetragonal zirconia polycrystalline (3Y-TZP) and nano-zirconia (NanoZr) are used in this study. MC3T3-E1 cells were seeded onto specimen surfaces and subjected to RNA interference (RNAi) for Syndecan-1, Syndecan-2, Syndecan-3, and Syndecan-4. At 48h post-transfection, the cell morphology, actin cytoskeleton, and focal adhesion were observed using scanning electron microscopy or laser scanning confocal fluorescence microscopy. At 24h and 48h post-transfection, cell counting kit-8 (CCK-8) assay was used to investigate cell proliferation. Results: The cell morphology of MC3T3-E1 cells on CpTi, 3Y-TZP, and NanoZr changed into abnormal shape after gene silencing of Syndecan. Among the Syndecan family, Sdc-2 is responsible for NanoZr-specific morphology regulation, via maintenance of cytoskeletal conformation without affecting cellular attachment. According to CCK-8 assay, Sdc-2 affects the osteoblastic cell proliferation onto NanoZr. Conclusion: Within the limitation of this study, we suggest that Syndecan affects osteoblastic cell adhesion on CpTi, 3Y-TZP, and NanoZr. Sdc-2 might be an important heparin-sensitive cell membrane regulator in osteoblastic cell adhesion, specifically on NanoZr, through the organization of actin cytoskeleton and affects osteoblastic cell proliferation.


Asunto(s)
Oseointegración/fisiología , Osteoblastos/citología , Osteoblastos/fisiología , Sindecanos/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Animales , Adhesión Celular/fisiología , Membrana Celular/efectos de los fármacos , Proliferación Celular/fisiología , Células Cultivadas , Ratones , Microscopía Electrónica de Rastreo , Oseointegración/genética , Propiedades de Superficie , Sindecano-2/genética , Sindecano-2/metabolismo , Sindecanos/genética , Titanio/química , Itrio/química , Circonio/química
15.
PLoS One ; 15(6): e0234524, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32579584

RESUMEN

The purpose of this study was to evaluate the adherence of streptococci to disks of titanium (commercially pure titanium: CpTi) and zirconia (tetragonal zirconia polycrystals: TZP). CpTi and yttria-stabilized TZP disks with a mirror-polished surface were used as specimens. The arithmetic mean surface roughness (Ra and Sa) and the surface wettability of the experimental specimens were measured. For analyzing the outermost layer of the experimental specimens, X-ray photoelectron spectroscopy (XPS) analysis was performed. Streptococcus sanguinis, S. gordonii, S. oralis, and S. mutans were used as streptococcal bacterial strains. These bacterial cultures were grown for 24 h on CpTi and TZP. The number of bacterial adhesions was estimated using an ATP-bioluminescent assay, and scanning electron microscope (SEM) observation of the adhered bacterial specimens was performed. No significant differences in surface roughness or wettability were found between CpTi and TZP. In XPS analyses, outermost layer of CpTi included Ti0 and Ti4+, and outermost layer of TZP included Zr4+. In the cell adhesion assay, the adherences of S. sanguinis, S. gordonii, and S. oralis to TZP were significantly lower than those to CpTi (p < 0.05); however, significant difference was not observed for S. mutans among the specimens. The adherence to CpTi and TZP of S. mutans was significantly lower than that of S. sanguinis, S. gordonii, and S. oralis. These results were confirmed by SEM. S. sanguinis, S. gordonii, and S. oralis adhered less to TZP than to CpTi, but the adherence of S. mutans was similar to both surfaces. S. mutans was less adherent compare with the other streptococci tested in those specimens.


Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Streptococcus sanguis/efectos de los fármacos , Titanio/química , Circonio/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Espectroscopía de Fotoelectrones , Streptococcus sanguis/química , Streptococcus sanguis/ultraestructura , Propiedades de Superficie/efectos de los fármacos , Itrio/química
16.
Niger J Clin Pract ; 23(6): 792-797, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32525113

RESUMEN

Background: There is no information about the shear bond strengths (SBS) of zirconia ceramic to primary tooth dentin. Aim: To investigate the effect of different surface treatments and cements on the shear bond strength (SBS) of zirconia ceramic to primary tooth dentin. Materials and Methods: Prepared zirconia bars were distributed into four groups according to surface treatment procedure: control, sandblasting, CoJet and hot etching. The zirconia specimens in each group were further divided into subgroups according to cement (n = 13): self-adhesive resin (Rely-X Unicem), resin-modified glass ionomer (Ketac-Cem Plus), and universal bioactive (BioCem). Zirconia specimens were bonded to the primary tooth dentin surface by cement. SBS was measured, and the data were subjected to two-way ANOVA and Tukey's tests. Results: Statistical differences were observed in the surface treatment procedures for Rely-X Unicem (P < 0.05), but no statistically significant differences were found in the sandblasting, CoJet and hot-etching groups for Ketac-Cem Plus (P > 0.05). For BioCem, the SBS value for the hot etching group was significantly lower than those for the CoJet and sandblasting groups (P < 0.05). The SBS values for the Rely-X Unicem subgroups (sandblasting, CoJet and hot etching) were significantly higher than those for the other cements (P < 0.05). Conclusion: The bond strength of zirconia ceramic to primary tooth dentin is affected by surface treatments and cements.


Asunto(s)
Cerámica/química , Recubrimiento Dental Adhesivo , Dentina , Cementos de Resina/química , Resistencia al Corte , Diente Primario , Circonio/química , Resinas Acrílicas , Adhesivos , Cementos de Ionómero Vitreo , Humanos , Ensayo de Materiales , Dióxido de Silicio , Propiedades de Superficie
17.
Food Chem ; 329: 127210, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32512388

RESUMEN

In this study, a novel, easy, rapid and green zirconium nanoparticles (Zr-NPs) based dispersive solid phase extraction (DSPE) method is presented for the precise and sensitive determination of selenium by slotted quartz tube-flame atomic absorption spectrophotometry (SQT-FAAS). Influential parameters of the extraction procedure were optimized by altering one parameter while keeping the other parameters constant. The optimum conditions were selected as 10 mg of Zr-NPs, 75 s vortex period, and 200 µL of concentrated HCl for 30 mL of sample/standard solution. The linear range of the developed method was found to be between 25 and 100 µg/L, and the respective limits of detection and quantification were 5.3 and 18 µg/L. About 415 folds enhancement in detection power was achieved by the optimized method relative to the conventional FAAS. Green tea samples were spiked and used for recovery experiments and the results obtained were between 92 and 102%.


Asunto(s)
Nanopartículas del Metal/química , Selenio/análisis , Espectrofotometría Atómica/métodos , Té/química , Circonio/química , Concentración de Iones de Hidrógeno , Límite de Detección , Reproducibilidad de los Resultados , Selenio/aislamiento & purificación , Extracción en Fase Sólida
18.
Chemosphere ; 258: 127370, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32554019

RESUMEN

Porous luffa plant fibre (LF) was grafted with Fe and Zr, and the ability of the fabricated adsorbents to remove arsenate (As(V)) from water was investigated in batch and column adsorption experiments. The Langmuir adsorption capacity (mg g-1) at pH 7 of LF was found to be 0.035, which increased to 2.55 and 2.89 after being grafted with Fe (FLF-3) and Zr (ZLF-3), respectively. Grafting with Fe and Zr increased the zeta potential and zero point of charge (ZPC) of LF (from pH 3.9 to 7.4 for Fe grafting and to 7.6 for Zr grafting), due to chemical bonding of the metals, possibly with the hydroxyl and carboxylic groups in LF as indicated in FTIR peaks. Zeta potential and ZPC decreased after As adsorption owing to inner-sphere complexation mechanism of adsorption. The increase of pH from 3 to 10 progressively reduced the adsorbents' adsorption capacity. Co-existing anions weakened the As(V) removal efficiency in the order, PO43- > SiO32- > CO32- > SO42-. Adsorption kinetics data fitted well to the Weber and Morris model, which revealed initial fast and subsequent slow rates of intra-particle As diffusion into the bigger pores and smaller pores, respectively. Column adsorption data fitted well to the Thomas model with the predicted adsorption capacities in the same order as in the batch adsorption experiment (ZLF-3 > FLF-3 > LF).


Asunto(s)
Arseniatos/análisis , Agua Potable/química , Hierro/química , Luffa/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Circonio/química , Adsorción , Agua Potable/normas , Concentración de Iones de Hidrógeno , Cinética
19.
Artículo en Inglés | MEDLINE | ID: mdl-32532181

RESUMEN

Diesel oil spills in marine environments pose a severe threat to both aquatic and terrestrial ecosystems. Photocatalysis is an environment-friendly method for marine oil remediation; however, its practical usage is limited due to several issues. In this study, we demonstrate the enhanced efficacy of doped CuO/ZrO2 photocatalyst at degrading marine diesel in comparison to undoped ZrO2. The photocatalysts were prepared using co-precipitation method, and their physical and chemical properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and ultraviolet-visible spectroscopy (UV-Vis). XRD analysis showed that the photocatalytic crystallite size of ZrO2 and CuO/ZrO2 was 28.80 nm and 40.32 nm, respectively. Both catalysts exhibited stable crystalline forms. UV-Vis analysis showed that doping of ZrO2 with CuO significantly reduced its band gap from 4.61 eV to 1.18 eV, thus enhancing the utilization of visible light. The effect of catalyst dosage, doping ratio, and initial diesel concentration on the degradation rate of diesel was investigated by performing single-factor experiments. The optimization experiment results showed that 96.96% of diesel could be degraded under visible light. This study laid an experimental foundation for expanding the practical applications of photocatalytic technology.


Asunto(s)
Cobre/química , Luz , Nanocompuestos/química , Contaminación por Petróleo/análisis , Contaminantes Químicos del Agua/análisis , Circonio/química , Catálisis , Ecosistema , Restauración y Remediación Ambiental , Modelos Teóricos , Oxidación-Reducción , Agua de Mar/química
20.
Proc Natl Acad Sci U S A ; 117(25): 14299-14305, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32513701

RESUMEN

The Lower Cretaceous Huajiying Formation of the Sichakou Basin in northern Hebei Province, northern China contains key vertebrate taxa of the early Jehol Biota, e.g., Protopteryx fengningensis, Archaeornithura meemannae, Peipiaosteus fengningensis, and Eoconfuciusornis zhengi This formation arguably documents the second-oldest bird-bearing horizon, producing the oldest fossil records of the two major Mesozoic avian groups Enantiornithes and Ornithuromorpha. Hence, precisely determining the depositional ages of the Huajiying Formation would advance our understanding of the evolutionary history of the Jehol Biota. Here we present secondary ion mass spectrometry (SIMS) U-Pb zircon analysis results of eight interbedded tuff/tuffaceous sandstone samples from the Huajiying Formation. Our findings, combined with previous radiometric dates, suggest that the oldest enantiornithine and ornithuromorph birds in the Jehol Biota are ∼129-131 Ma, and that the Jehol Biota most likely first appeared at ∼135 Ma. This expands the biota's temporal distribution from late Valanginian to middle Aptian with a time span of about 15 My.


Asunto(s)
Biota , Aves/clasificación , Plomo/química , Silicatos/química , Circonio/química , Animales , Evolución Biológica , China , Fósiles , Geología , Filogenia , Espectrometría de Masa de Ion Secundario
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