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41.
Magnetobiosensors Based on Viral Protein p19 for MicroRNA Determination in Cancer Cells and Tissues 下载免费PDF全文
Dr. Susana Campuzano Dr. Eva López‐Hernández Felipe Conzuelo Dr. Rosario Granados Dr. José M. Sánchez‐Puelles Prof. José M. Pingarrón 《Angewandte Chemie (International ed. in English)》2014,53(24):6168-6171
MicroRNAs (miRs) have emerged as important clinical biomarkers with both diagnostic and prognostic value for relevant diseases, such as cancer. MiRs pose unique challenges for detection and are currently detected by northern blotting, real‐time PCR, and microarray techniques. These expensive, complicated, and time‐consuming techniques are not feasible for on‐site miR determination. In this study, amperometric magnetobiosensors involving RNA‐binding viral protein p19 as a selective biorecognition element were developed for miR quantification. The p19‐based magnetosensors were able to detect 0.4 fmol of a synthetic target and endogenous miR‐21 (selected as a model for its role in a wide variety of cancers) in only 2 h in total RNA extracted from cancer cells and human breast‐tumor specimens without PCR amplification and sample preprocessing. These results open up formidable perspectives for the diagnosis and prognosis of human cancers and for drug‐discovery programs. 相似文献
42.
I.C. Sophiana A. Topandi F. Iskandar H. Devianto N. Nishiyama Y.W. Budhi 《Materials Today Chemistry》2020
Mesoporous Ce0.75Zr0.25O2 solid solution powders were successfully synthesized by a co-precipitation method. A combination of 10 wt% copper oxide, manganese oxide, and nickel oxide was added to the Ce0.75Zr0.25O2 support by impregnation method and calcined in the air with a flow rate of 2 ml s?1 at 400 °C for 4 h. All catalysts were characterized using Hydrogen Temperature Programmed Reduction (H2-TPR), X-ray Diffraction (XRD), and Brunauer-Emmet-Teller (BET) isotherm methods to find the interaction between metals, the crystallinity of the catalyst, surface area and pore volume of the catalyst, respectively. The 3.3% CuO-3.3% MnO2-3.3% NiO/Ce0.75Zr0.25O2 catalyst showed higher catalytic activity for benzene oxidation with benzene conversion of 90% at 250 °C and weight hourly space velocity (72,000 mL g?1 h?1) when compared to one metal oxide only. This finding presents a high activity and low-cost catalysts for removing a very lean concentration of benzene containing in the industrial flue gas at low temperatures. 相似文献
43.
M.A. Mujawar H. Gohel S.K. Bhardwaj S. Srinivasan N. Hickman A. Kaushik 《Materials Today Chemistry》2020
Biosensors are emerging as efficient (sensitive and selective) and affordable analytical diagnostic tools for early-stage disease detection, as required for personalized health wellness management. Low-level detection of a targeted disease biomarker (pM level) has emerged extremely useful to evaluate the progression of disease under therapy. Such collected bioinformatics and its multi-aspects-oriented analytics is in demand to explore the effectiveness of a prescribed treatment, optimize therapy, and correlate biomarker level with disease pathogenesis. Owing to nanotechnology-enabled advancements in sensing unit fabrication, device integration, interfacing, packaging, and sensing performance at point-of-care (POC) has rendered diagnostics according to the requirements of disease management and patient disease profile i.e. in a personalized manner. Efforts are continuously being made to promote the state of art biosensing technology as a next-generation non-invasive disease diagnostics methodology. Keeping this in view, this progressive opinion article describes personalized health care management related analytical tools which can provide access to better health for everyone, with overreaching aim to manage healthy tomorrow timely. Considering accomplishments and predictions, such affordable intelligent diagnostics tools are urgently required to manage COVID-19 pandemic, a life-threatening respiratory infectious disease, where a rapid, selective and sensitive detection of human beta severe acute respiratory system coronavirus (SARS-COoV-2) protein is the key factor. 相似文献
44.
BaGd2O4, BaLa2O4 and SrLa2O4 powders doped with different concentrations of Eu3+ or Tb3+ are prepared by combustion synthesis method and the samples were further heated to 500, 700 and 900 °C to improve the crystallinity of the materials. The structure and morphology of materials have been examined by X-ray diffraction and scanning electron microscopy. It is remarkable that all the samples of BaGd2O4, BaLa2O4 and SrLa2O4 have similar morphology. The SEM images show homogeneous aggregates of varying shapes and sizes, which are composed of a large number of small elliptical shaped crystallites with an average diameter of about 0.5-3.0 μm. Photoluminescence for all materials increases with increase of temperature and shows a maximum for the samples heated to 900 °C with 4 mole% doping of Eu3+ or Tb3+ ions. The luminescence is almost same for all powders when doped with same concentration of Eu3+. 相似文献
45.
M. Ivković M.A. Gonzalez S. Jovićević M.A. Gigosos N. Konjević 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The results of an experimental study of the He I 447.1 nm line and its forbidden component at high electron number density are presented and compared with profiles calculated using computer simulation method. Michelson interferometer at 632.8 nm was used to measure plasma electron number density in the range (1–7) × 1023 m− 3 while electron temperatures for the same experimental conditions in the range of 25 000 K to 35 000 K were determined using several spectroscopic techniques. The agreement of experimental overall line shape with computer simulation results is within 10% of what is well within theoretical and experimental uncertainty. This favorable comparison enabled the development of a simple approximate formula for the evaluation of electron number density from the measurement of wavelength separation between peaks of allowed and forbidden lines. This technique of plasma diagnostics is not sensitive to the presence of self-absorption of strong He I allowed line. The derivation of approximate formula with estimated accuracy of 15% was followed by detailed comparison with other experimental and theoretical data. 相似文献
46.
Fengtao Jin Tianxuan Huang Yongkun Ding Zhijian Zheng Jianmin Yuan 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(1):78-86
The orbital relaxation effect was studied in the calculations and diagnostics of the L-shell absorption spectra (2p→3d,4d,5d) of iron and bromine plasmas. A detailed level accounting model was developed to calculate the huge number of L-shell absorption lines of the two typical mid-Z plasmas. The orbital sets were generated by the optimizations according to the initial and final states, respectively. It was found that the L-shell line positions agree with the experimental iron and bromine spectra better when the orbital relaxations were included in calculations. Since experimental mid-Z spectra have few detailed line structures, calculations without considering orbital relaxations may misinterpret the spectra and consequently lead to underestimations of the plasma temperatures. 相似文献
47.
Suchinder K. Sharma Shreyas S. Pitale T.K. GunduRao M.S. Qureshi 《Journal of luminescence》2010,130(2):240-248
A simple solution combustion synthesis route for preparation of Cu-doped SrAl4O7 has been described. Average particle size of 33 nm and platelet-like morphology has been observed. ESR studies confirm the presence of Cu in polycrystalline SrAl4O7. Bright-green luminescence under near-UV irradiation arising due to transition between Cu+ levels with microsecond level decay time makes it suitable for application in phosphor converted light emitting diode (LED). TL measurements show broad glow peaks which when deconvoluted indicate activation energies in the range of 0.6-1.1 eV and elucidate the trapping dynamics. 相似文献
48.
Various well dried solid celluloses, such as nativecelluloses from different sources, different pulps and regenerated cellulosefibers were compared by dielectric relaxation spectroscopy (DRS) in the lowfrequency (10 mHz to 5 MHz) and low temperature(–130 to 20 °C) range. No significant differences werefound in the polymeric dynamics. In addition, the influence of the watercontenton the -relaxation and the wet relaxation wasinvestigated for morphologically very different celluloses such as cottonlinters, highly amorphous bead cellulose and lyocell fibers. The lyocell fiberswere investigated in the unmodified form and after modification by a treatmentwith alkali, after mild bleaching and after chemical crosslinking. It was foundthat the water content influences the dielectric dynamics and the intensityparameters differently for these different materials. NaOH-activation usingdifferent lye concentrations also influenced the dielectric dynamics. Finally,opportunities and limitations of DRS as a diagnostic tool are discussed. 相似文献
49.
Eva?Chinarro Ana?Maria?Segad?esEmail author José?Ramón?Jurado 《Journal of Solid State Electrochemistry》2004,8(9):606-610
Metals and ceramics can behave as active electrocatalyst materials, particularly in hydrocarbon oxidation in anodic reaction fuel cells. Combustion synthesis is a very reliable, fruitful and rapid synthesis method to produce metals, ceramics and cermets with low particle size and high specific surface area. This work describes the preparation of nanoparticle Pt/Ru alloys, ceramic perovskites such as Sm0.95CoO3–, and Sm0.95CoO3–/Pt cermets, and shows how promising these materials can be in the role of electrochemically active materials.Presented at the OSSEP Workshop Ionic and Mixed Conductors: Methods and Processes, Aveiro, Portugal, 10–12 April 2003 相似文献
50.
Asger Hobolth Jan Pedersen Eva B. Vedel Jensen 《Annals of the Institute of Statistical Mathematics》2003,55(2):227-242
In this paper we propose a flexible continuous parametric shape model for star-shaped planar objects. The model is based on
a polar Fourier expansion of the normalized radius-vector function. The expected phase amplitudes are modelled by a simple
regression with parameters having nice geometric interpretations. The suggestedgeneralized p-order model is an extension of first- and second-order Gaussian shape models, and in particular the Gaussian assumption is relaxed. The
statistical analysis is straightforward, as demonstrated by an application concerning shape discrimination of two cell nuclei
populations. 相似文献