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Metallic implantation materials having high yield strength, low elastic modulus, and non-cytotoxic alloying elements would be advantageous for the long-term stability of implants. This study assessed the surface and mechanical properties, and also in vitro osteoconductivity of ultrafine-grained (UFG) Ti-13Nb-13Zr alloy produced by dynamic globularization without any severe deformation for future biomedical applications as an endosseous implant material. The surface characteristics and mechanical properties were investigated by orientation image microscopy, contact angle measurements, optical profilometry, and uniaxial tension tests. Mouse calvaria-derived pre-osteoblastic cell (MC3T3-E1) attachment, spreading, viability, alkaline phosphatase (ALP) activity, and quantitative analysis of osteoblastic gene expression on UFG Ti-13Nb-13Zr alloy were compared with coarse-grained (CG) Ti-13Nb-13Zr and CG Ti-6Al-4V alloys. Dynamic globularized Ti-13Nb-13Zr alloy has an ultrafine grain size (0.3 μm) and an excellent combination of yield strength and elastic modulus compared with CG alloys, which displayed significantly lower water contact angles compared with CG alloys ( P<0.05). The UFG and CG Ti-13Nb-13Zr alloys displayed significantly increased cellular attachment compared with CG Ti-6Al-4V alloy ( P<0.05). The UFG Ti-13Nb-13Zr supported better cell spreading and more numerous focal adhesions. ALP activity ( P<0.05) and mRNA expressions of the osteoblast transcription factor genes (osterix, Runx2) and marker gene for osteoblast differentiation (osteocalcin) were markedly increased in cells grown on the UFG substrate compared with CG substrates at early incubation timepoints. Enhanced pre-osteoblast response to UFG Ti-13Nb-13Zr substrate is attributable to the non-cytotoxic alloying elements and the submicron scale grain size contributes to the superior surface hydrophilicity and abundant grain boundaries favorable for cell behavior. These findings indicate that dynamic globularized UFG Ti-13Nb-13Zr alloy is promising for load-bearing endosseous implant material because of excellent mechanical and biological compatibilites. Park CH, Lee CS, Kim Y-J, Jang J-H, Suh J-Y, Park J-W. Improved pre-osteoblast response and mechanical compatibility of ultrafine-grained Ti-13Nb-13Zr alloy. Clin. Oral Impl. Res. , 2011; 735-742 doi: 10.1111/j.1600-0501.2010.02053.x [ABSTRACT FROM AUTHOR]

Ursodeoxycholic acid (UDCA) is a tertiary bile acid synthesized by the liver and has various functions such as promoting bile secretion, antibacterial effect, inflammatory treatment, cholesterol reduction, and degradation. UDCA seems to be a material that can be applied in many aspects, such as adding it to implant coating materials or wound coatings. However, until now, only experiments and studies have been conducted to administer UDCA orally as a drug. In this paper, research was conducted to serve as a foothold for the application of UDCA to in vitro research. In this study, polymer fibers were prepared using electrospinning technology by mixing UDCA with Polycaprolactone(PCL), a biocompatible polymer. Through various analyses, it was confirmed that UDCA was contained in the electrospun membrane. In addition, it was confirmed that UDCA functions properly through the appearance of antimicrobial properties in antimicrobial experiments. The PCL/UDCA electrospun fiber prepared in this study and the analysis results using it show that UDCA can be applied not only to oral drugs but also to various fields such as wound coverings and stent coating membranes. [ABSTRACT FROM AUTHOR]

Developing mechanical energy harvesters for electrical stimulation (ES) needed to augment cell behavior is a burgeoning area of interest. Mechanical energy harvesters that can generate electrical energy in electrolyte‐containing aqueous environments offer a unique solution for delivering ES to cells. In this work, a fully integrated ES assembly (FESA) is introduced that comprises coiled polydopamine (PDA) containing carbon nanotube yarn (CNT) harvesters, serving as ES generators, and poly(3,4‐ethylenedioxythiophene) coated carbon nanotube (PEDOT/CNT) sheets employed as a conductive scaffold. The PDA containing CNT (PDA/CNT) yarn, a novel twistron electrode, achieves an enhanced electrical power at a lower matching impedance than coiled CNT yarn to efficiently transfer ES to the conductive scaffold. The PEDOT used for the scaffold provides a suitable surface for cell adhesion and low resistance for effective ES transmission. In addition, the upscaled array of coiled PDA/CNT yarns provides an ES current density range up to 75.4 µA cm−2, which is much higher than for ES systems using different mechanical energy harvesters. This FESA is designed to provide an optimal level of ES for the proliferation and differentiation of chondrocytes. The findings illuminate the potential of chemically modified twistron energy harvesters as an innovative and effective strategy to promote biological response. [ABSTRACT FROM AUTHOR]

Single‐atomic catalysts based on ruthenium have a balanced efficiency for water splitting, but it is necessary to control their activity and durability. In this work, a binder‐free Fe2‐xRuxNb2O6 (FRNO) hybrid catalyst is rationally designed through a facile hydrogel‐crosslinking route. The as‐prepared FRNO catalyst exhibits high electrocatalytic activity and stability when operating under acidic (0.5 m H2SO4) and alkaline (1 m KOH) media. Operando X‐ray adsorption and density functional theory calculations show that FRNO/CC, with its high intrinsic conductivity, promotes the adsorption and dissociation of water on its surface by regulating the charge distribution via charge transfer to the coordinated surface oxygen. This facilitates the oxygen evolution reaction (OER) performance by stabilizing *OOH adsorption on Ru and Fe. The FRNO/carbon cloth (CC) hybrid catalyst also delivers excellent activity and stability for both hydrogen evolution reaction (HER) and OER in pH‐universal electrolytes with low overpotentials of 30 mV per 82 mV for HER and 200 mV per 260 mV for OER at a current density of 10 mA cm‐2 in acidic/basic medium. Ultimately, the FRNO/CC hybrid catalyst shows good water‐splitting performance, and it is expected to help contribute to the creation of various hybrid electrocatalysts. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma (CCA) is a fatal disease often detected late in unresectable stages. Currently, there are no effective diagnostic methods or biomarkers to detect CCA early with high confidence. Analysis of tumor-derived extracellular vesicles (tEVs) harvested from liquid biopsies can provide a new opportunity to achieve this goal. Here, an advanced nanoplasmonic sensing technology is reported, termed FLEX (fluorescence-amplified extracellular vesicle sensing technology), for sensitive and robust single EV analysis. In the FLEX assay, EVs are captured on a plasmonic gold nanowell surface and immunolabeled for cancer-associated biomarkers to identify tEVs. The underlying plasmonic gold nanowell structures then amplify EVs' fluorescence signals, an effective amplification process at the single EV level. The FLEX EV analysis revealed a wide heterogeneity of tEVs and their marker levels. FLEX also detected small tEVs not detected by conventional EV fluorescence imaging due to weak signals. Tumor markers (MUC1, EGFR, and EPCAM) are identified in CCA, and this marker combination is applied to detect tEVs in clinical bile samples. The FLEX assay detected CCA with an area under the curve of 0.93, significantly better than current clinical markers. The sensitive and accurate nanoplasmonic EV sensing technology can aid in early CCA diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: An implantable anticancer device (IAD) amenable to eradicate local regional recurrence (LRR) of breast cancer as well as to enhance the breast reconstruction during/after therapy is proposed for the first time. The IAD is fabricated by incorporating the superparamagnetic graphene oxide doxorubicin nanocomposite of size ≈200 nm in a nanofiber matrix to enable the sustained and tumor specific anticancer drug release over 60 d in vitro with a minimum initial burst release and the repeated hyperthermic capability in an alternating magnetic field to ensure the synergistic inhibition of LRR. The IAD also enriches the reconstruction of poor breast cosmesis that resulted from the surgical treatment by supporting the lipofilling of the surgical residual cavity to induce the adipogenic process. Moreover, the noninvasive monitoring capability of IAD through magnetic resonance imaging augments to the effective patient care. Thus, this work reports a new and reliable concept by introducing the multifunctional IAD possessing enhanced specificity with a real‐time monitoring capability and long‐term anticancer efficacy as a potential platform for synergistic inhibition of LRR and a great promise for the in situ breast reconstruction ability for better breast cosmesis. [ABSTRACT FROM AUTHOR]

In this work, we investigate the enhanced performance of amorphous indium zinc oxides-based thin film transistors with hafnium silicate (HfSiOx) gate insulators. HfSiOx gate insulators annealed at various conditions are deposited by cosputtering of hafnium oxide and Si. The structural properties of HfSiOx are investigated using the atomic force microscopy, X-ray diffraction, and x-ray photoelectron spectroscopy (XPS). techniques. Furthermore, the electrical characteristics of HfSiOx are analyzed to investigate the effect of annealing conditions. We obtain optimal results for thin film transistors with HfSiOx gate insulators annealed for 1 h at 100 °C, with a saturation mobility of 1.2 cm2/V · s, threshold voltage of 2.2 V, on current/off current ratio of 2.0 × 106, and an insulator surface roughness of 0.187 nm root mean square. [ABSTRACT FROM AUTHOR]

A method for the versatile synthesis of novel, mussel-inspired, electrospun nanofibers with catechol moieties is reported. These mussel-inspired nanofibers are used to bind iron oxide nanoparticles (IONPs) and the borate-containing anticancer drug Bortezomib (BTZ) through a catechol metal binding mechanism adapted from nature. These smart nanofibers exhibit a unique conjugation of Bortezomib to their 1, 2-benzenediol (catechol) moieties for enabling a pH-dependent drug delivery towards the cancer cells and the IONPs via strong coordination bonds for exploiting the repeated application of hyperthermia. Thus the synergistic anticancer effect of these mussel-inspired magnetic nanofibers were tested in vitro for the repeated application of hyperthermia along with the chemotherapy and found that the drug-bound catecholic magnetic nanofibers exhibited excellent therapeutic efficacy for potential anticancer treatment. [ABSTRACT FROM AUTHOR]

Mechanotransduction: Regulating Electrical Cue and Mechanotransduction in Topological Gradient Structure Modulated Piezoelectric Scaffolds to Predict Neural Cell Response (Adv. Funct. In article number 1907330, Chan Hee Park, Cheol Sang Kim, and co-workers develop tunable topography modulated piezoelectric fibrous scaffolds that can regulate electrical cues and mechanotransduction to predict neural cell response. YAP translocation in cells provide clues to how cells respond to topological gradient structure-modulated piezoelectric scaffolds. [Extracted from the article]

Neural cells respond to topographical cues with alterations in cell growth and neurite sprouting mediated by changes in cell behavior. The interaction of fiber topography with cell adhesion receptors affects how the cells adhere to the surface of fibers and defines cell fate through alterations in the biochemistry, physiology, and morphology of neural cells. Although previous studies suggest topographical features influence neural cell proliferation and neurite sprouting, only a few studies have attempted to assess the use of both electrical and topological cues in piezoelectric scaffolds for nerve regeneration. In this study, variations in the shape‐modified collectors enable tunable surface topographic constructs, from micropatterns to fiber bundle structure. The crystallinity, chemical composition, and quantitative analysis confirm that the interplay between the topological structures of the fibers and the blending of nanocomposite materials is critical for the formation of the β‐phase. It is found that the topographical features and induced electrical characteristics affect cell growth. Also, the intracellular signaling pathway is induced that can provide clues as to how neural cells respond to the topological gradient structure modulated piezoelectric scaffolds. An analysis of the neuron‐specific cytoskeletal related markers further reveals that the specific topographical features piezoelectric fibrous scaffold reinforces neuron‐specific cytoskeletal proteins and microtubule assembly. [ABSTRACT FROM AUTHOR]