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1.
J Glob Antimicrob Resist ; 32: 104-107, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36764658

RESUMEN

OBJECTIVES: Around the globe, escalation in rare opportunistic microbial infections is alarming as they are heading steadily towards 'superbug' status. In aquatic ecosystems, plastic fosters multidrug-resistant pathogenic bacteria and plays a significant role in trafficking antibiotic-resistant genes. In this study, we focused on a multidrug-resistant bacterial strain isolated from microbial communities found on plastic substrates of a volcanic lake in central Italy. METHODS: Extended-spectrum beta-lactamase-producing strains were isolated from both raw water and plastic substrates for a comparative investigation using microbiological and molecular methods, and antibiotic susceptibility profiling was performed against a panel of ten antibiotics. RESULTS: Molecular identification and Basic Local Alignment Search Tool analysis confirmed an almost identical sequencing pattern of two isolated strains and their homology with Morganella morganii. Antibiotic susceptibility tests revealed their resistance to almost all tested antibiotics. Class 1 integron-associated gene (intI1) and seven antibiotic resistance genes were detected in both strains, confirming their superbug status. CONCLUSION: To our knowledge, this is the first study on the characterization of extended-spectrum beta-lactamase-producing M. morganii isolated from the biofilm of plastic substrates, depicting the potential toxicity of plastic in harbouring and dispersing virulent, multidrug-resistant, opportunistic human pathogens.


Asunto(s)
Infecciones por Enterobacteriaceae , Morganella morganii , Humanos , Morganella morganii/genética , Ecosistema , Infecciones por Enterobacteriaceae/microbiología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
2.
Polymers (Basel) ; 13(3)2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33513938

RESUMEN

Plastics are used in cover substrates for billboards, windows, large LED signboards, lighting devices, and solar panels because they are transparent and can be colored and shaped as desired. However, when plastic cover substrates installed in outdoor environments are constantly exposed to harsh conditions such as snow, rain, dust, and wind, their transparency deteriorates owing to watermarks and dust contamination. Herein, we investigated a simple dipping-press coating method that can impart hydrophobicity while maintaining the transparency, regardless of the plastic substrate type. A highly transparent and hydrophobic coating film was formed on a plastic substrate by a two-step process, as follows: (1) application of a polydimethylsiloxane-octadecylamine coating by a dipping process, and (2) embedding (1H,1H,2H,2H-heptadecafluorodec-1-yl) phosphonic acid-aluminum oxide nanoparticles by a thermal press process. The plastic substrates on which the highly transparent and hydrophobic coating film was formed showed 150° or higher hydrophobicity and 80% or higher visible light transparency. The coating method proposed herein can easily impart hydrophobicity and is compatible with any plastic substrate that must maintain prolonged transparency without contamination when exposed to adverse conditions.

3.
Nanomaterials (Basel) ; 10(6)2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32585985

RESUMEN

A growth scheme at a low processing temperature for high crystalline-quality of ZnO nanostructures can be a prime stepping stone for the future of various optoelectronic devices manufactured on transparent plastic substrates. In this study, ZnO nanorods (NRs) grown by the hydrothermal method at 150 °C through doping of transition metals (TMs), such as Co, Ni, or Co-plus-Ni, on polyethylene terephthalate substrates were investigated by various surface analysis methods. The TM dopants in ZnO NRs suppressed the density of various native defect-states as revealed by our photoluminescence and X-ray photoelectron spectroscopy analysis. Further investigation also showed the doping into ZnO NRs brought about a clear improvement in carrier mobility from 0.81 to 3.95 cm2/V-s as well as significant recovery in stoichiometric contents of oxygen. Ultra-violet photodetectors fabricated with Co-plus-Ni codoped NRs grown on an interdigitated electrode structure exhibited a high spectral response of ~137 A/W, on/off current ratio of ~135, and an improvement in transient response speed with rise-up and fall-down times of ~2.2 and ~3.1 s, respectively.

4.
ACS Appl Mater Interfaces ; 12(23): 25616-25624, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32426973

RESUMEN

A novel strategy to functionalize transparent flexible plastic films with an optical ion-sensing layer using an inkjet-printing technology is described. The hydrophobic sensing chemicals that include a sodium ionophore, a lipophilic proton chromoionophore, and a lipophilic ion-exchanger are co-deposited onto substrates such as transparent polyester film sheets in the absence of any plasticizer and/or hydrophobic polymer matrix. The inkjet-printing process enables the formation of optode films with nanoscale thickness/roughness that readily facilitate interfacing with aqueous samples. Using a smartphone detector, the colorimetric response of the optodes is shown to reach 95% of equilibrium values within 100 s in response to different concentrations of sodium ions, which is more rapid than traditional ion-selective optodes based on plasticized PVC films as the sensing layer. The new optodes also exhibit high selectivity to Na+ over interfering ions including K+, Ca2+, and Mg2+. Chemical leaching experiments show that the highly hydrophobic optode components remain in place on the plastic substrate surface. Hence, excellent sensor stability and fully reversible optical responses are obtained, which is essential for potential continuous monitoring applications. Further testing of the sensors with undiluted human sweat samples is shown to yield accurate values for sodium concentrations. Therefore, the use of plasticizer-free ion-selective optode nanolayers that enable highly selective ion sensing on a clear plastic support is likely to expand the range of available chemical sensors suited for preparing wearable real-time sweat analysis devices.


Asunto(s)
Celulosa/análogos & derivados , Poliésteres/química , Sodio/análisis , Sudor/química , Celulosa/química , Colorimetría/instrumentación , Colorimetría/métodos , Tinta , Ionóforos/química , Membranas Artificiales , Óptica y Fotónica/instrumentación , Impresión/instrumentación , Teléfono Inteligente
5.
Biol Open ; 9(2)2020 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-31941700

RESUMEN

One of the main challenges relating to tendons is to understand the regulators of the tendon differentiation program. The optimum culture conditions that favor tendon cell differentiation have not been identified. Mesenchymal stem cells present the ability to differentiate into multiple lineages in cultures under different cues ranging from chemical treatment to physical constraints. We analyzed the tendon differentiation potential of C3H10T1/2 cells, a murine cell line of mesenchymal stem cells, upon different 2D- and 3D-culture conditions. We observed that C3H10T1/2 cells cultured in 2D conditions on silicone substrate were more prone to tendon differentiation, assessed with the expression of the tendon markers Scx, Col1a1 and Tnmd as compared to cells cultured on plastic substrate. The 3D-fibrin environment was more favorable for Scx and Col1a1 expression compared to 2D cultures. We also identified TGFß2 as a negative regulator of Tnmd expression in C3H10T1/2 cells in 2D and 3D cultures. Altogether, our results provide us with a better understanding of the culture conditions that promote tendon gene expression and identify mechanical and molecular parameters upon which we could act to define the optimum culture conditions that favor tenogenic differentiation in mesenchymal stem cells.


Asunto(s)
Técnicas de Cultivo de Célula , Diferenciación Celular , Fenómenos Mecánicos , Tendones/citología , Tendones/fisiología , Animales , Biomarcadores , Diferenciación Celular/genética , Células Cultivadas , Expresión Génica , Perfilación de la Expresión Génica , Ratones , Transcriptoma
6.
Stomatologiia (Mosk) ; 97(6): 72-77, 2018.
Artículo en Ruso | MEDLINE | ID: mdl-30589431

RESUMEN

The purpose of this article was to discuss the need for the introduction of the concepts of 'vicryl situational frame' and 'the plastic substrate', in which the first one updates the shape-generating aspect of reconstruction, the second one - its volume-generating aspect. The latter is described as a new surgical technique. The great importance of a new level of methodological and methodical support the method of GBR, which determines the high clinical and prognostic indicators of effectiveness was concluded.


Asunto(s)
Regeneración Ósea , Regeneración Tisular Guiada Periodontal
7.
Biosens Bioelectron ; 101: 235-244, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29096361

RESUMEN

Quantitative polymerase chain reaction (qPCR) renders profiling of genes of interest less time-consuming and cost-effective. Recently, multiplex profiling of miRNAs has enabled identifying or investigating predominant miRNAs for various diseases such as cancers and neurodegenerative diseases. Conventional multiplex qPCR technologies mostly use colorimetric measurements in solution phase, yet not only suffer from limited multiplexing capacity but also require target-screening processes due to non-specific binding between targets and primers. Here, we present hydrogel micropost-based qPCR for multiplex detection of miRNAs associated with Alzheimer's disease (AD). Our methodology promises two key advantages compared with the conventional solution-based PCR: 1) nearly no non-specific crosstalks between targets and primers, and 2) practically valuable multiplexing by spatial encoding within a single microchamber. Specifically, we immobilized hydrogel microposts (~ 400µm in diameter) within commercially available polycarbonate PCR chips by multi-step ultraviolet (UV, 365nm) exposure. We optimized this photoimmobilization for thermal cycles of PCR as well. Acrylated forward primers incorporated in polyethylene glycol diacrylate (PEGDA) posts played a crucial role to confine fluorescent signal of cDNA amplification within the PEGDA hydrogel. To demonstrate the potential of our platform, we successfully verified multiplex detection of five miRNAs, which were reported to be highly correlated with AD, from a complex buffer of human plasma.


Asunto(s)
Enfermedad de Alzheimer/genética , Hidrogel de Polietilenoglicol-Dimetacrilato/química , MicroARNs/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Polietilenglicoles/química , Enfermedad de Alzheimer/sangre , Técnicas Biosensibles/métodos , ADN Complementario/genética , Humanos , MicroARNs/análisis , MicroARNs/sangre
8.
ACS Appl Mater Interfaces ; 9(10): 8774-8782, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28211995

RESUMEN

The inkjet-printing process of precursor solutions containing In nitrate dissolved in 2-methoxyethanol is optimized using ethylene glycol as a cosolvent that allows the stabilization of the droplet formation, leading to a robust, repeatable printing process. The inkjet-printed precursor films are then converted to In2O3 semiconductors at flexible-substrate-compatible low temperatures (150-200 °C) using combined far-ultraviolet (FUV) exposure at ∼160 nm and thermal treatment. The compositional nature of the precursor-to-metal oxide conversion is studied using grazing incidence X-ray diffraction (GIXRD), X-ray reflectivity (XRR), and Fourier transform infrared (FTIR) spectroscopy that indicate that amorphous, high density (up to 5.87 g/cm3), and low impurity In2O3 films can be obtained using the combined annealing technique. Prolonged annealing (180 min) at 150 °C yields enhancement-mode TFTs with saturation mobility of 4.3 cm2/(Vs) and ∼1 cm2/(Vs) on rigid Si/SiO2 and flexible plastic PEN substrates, respectively. This paves the way for manufacturing relatively high-performance, printed metal-oxide TFT arrays on cheap, flexible substrate for commercial applications.

9.
ACS Appl Mater Interfaces ; 8(50): 34513-34519, 2016 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-27998139

RESUMEN

Amorphous, sol-gel processed, indium gallium zinc oxide (IGZO) transistors on plastic substrate with a printable gate dielectric and an electron mobility of 4.5 cm2/(V s), as well as a mobility of 7 cm2/(V s) on solid substrate (Si/SiO2) are reported. These performances are obtained using a low temperature pulsed light annealing technique. Ultraviolet (UV) pulsed light system is an innovative technique compared to conventional (furnace or hot-plate) annealing process that we successfully implemented on sol-gel IGZO thin film transistors (TFTs) made on plastic substrate. The photonic annealing treatment has been optimized to obtain IGZO TFTs with significant electrical properties. Organic gate dielectric layers deposited on this pulsed UV light annealed films have also been optimized. This technique is very promising for the development of amorphous IGZO TFTs on plastic substrates.

10.
Adv Mater ; 27(35): 5223-9, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26257314

RESUMEN

By plasma-enhanced chemical vapor deposition, a molybdenum disulfide (MoS2 ) thin film is synthesized directly on a wafer-scale plastic substrate at below 300 °C. The carrier mobility of the films is 3.74 cm(2) V(-1) s(-1) . Also, humidity is successfully detected with MoS2 -based sensors fabricated on the flexible substrate, which reveals its potential for flexible sensing devices.

11.
ACS Appl Mater Interfaces ; 6(18): 16249-56, 2014 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-25162375

RESUMEN

Polypyrrole/reduced graphene oxide (PPy/RGO) composites on the rigid and plastic conducting substrates were fabricated via a facile two-step electrochemical process at low temperature. The polypyrrole/graphene oxide (PPy/GO) composites were first prepared on the substrate with electrochemical polymerization method, and the PPy/RGO composites were subsequently obtained by electrochemically reducing the PPy/GO. The resultant PPy/GO and PPy/RGO composites were porous, in contrast to the dense and flat pristine PPy films. The cyclic voltammetry measurement revealed that resultant composites exhibited a superior catalytic performance for triiodide reduction in the order of PPy/RGO > PPy/GO > PPy. The catalytic activity of PPy/RGO was comparable to that of Pt counter electrode (CE). Under the optimal conditions, an energy conversion efficiency of 6.45% was obtained for a rigid PPy/RGO-based dye-sensitized solar cell, which is 90% of that for a thermally deposited Pt-based device (7.14%). A plastic counter electrode was fabricated by depositing PPy/RGO composites on the plastic ITO/PEN substrate, and then an all-plastic device was assembled and exhibited an energy conversion efficiency of 4.25%, comparable to that of the counterpart using a sputtered-Pt CE (4.83%) on a plastic substrate. These results demonstrated that electrochemical synthesis is a facile low-temperature method to fabricate high-performance RGO/polymer composite-based CEs for plastic DSCs.

12.
Sensors (Basel) ; 10(10): 9118-26, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22163398

RESUMEN

In this study, a laterally coupled device composed of a photodiode and a Si nanowires-field-effect transistor (NWs-FET) is constructed on a plastic substrate and the coupled device is characterized. The photodiode is made of p-type Si NWs and an n-type ZnO film. The Si NWs-FET is connected electrically to the photodiode in order to enhance the latter's photocurrent efficiency by adjusting the gate voltage of the FET. When the FET is switched on by biasing a gate voltage of -9 V, the photocurrent efficiency of the photodiode is three times higher than that when the FET is switched off by biasing a gate voltage of 0 V.


Asunto(s)
Nanocables/química , Plásticos/química , Silicio/química , Transistores Electrónicos , Óxido de Zinc/química , Propiedades de Superficie
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