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971.
Brain tumors are the most common malignant primary intracranial tumors of the central nervous system. They are often recognized too late for successful therapy. Minimally invasive methods are needed to establish a diagnosis or monitor the response to treatment of CNS tumors. Brain tumors release molecular information into the circulation. Liquid biopsies collect and analyze tumor components in body fluids, and there is an increasing interest in the investigation of liquid biopsies as a substitute for tumor tissue. Tumor-derived biomarkers include nucleic acids, proteins, and tumor-derived extracellular vesicles that accumulate in blood or cerebrospinal fluid. In recent years, circulating tumor cells have also been identified in the blood of glioblastoma patients. In this review of the literature, the authors highlight the significance, regulation, and prevalence of molecular biomarkers such as O6-methylguanine-DNA methyltransferase, epidermal growth factor receptor, and isocitrate dehydrogenase. Herein, we critically review the available literature on plasma circulating tumor cells (CTCs), cell-free tumors (ctDNAs), circulating cell-free microRNAs (cfmiRNAs), and circulating extracellular vesicles (EVs) for the diagnosis and monitoring of brain tumor. Currently available markers have significant limitations. While much research has been conductedon these markers, there is still a significant amount that we do not yet understand, which may account for some conflicting reports in the literature. 相似文献
972.
973.
Syed Muhammad Muntazir Mehdi Sivakumar Krishnamoorthy Michal Wojciech Szczesniak Agnieszka Ludwikw 《International journal of molecular sciences》2021,22(13)
miRNAs are involved in various biological processes, including adaptive responses to abiotic stress. To understand the role of miRNAs in the response to ABA, ABA-responsive miRNAs were identified by small RNA sequencing in wild-type Arabidopsis, as well as in abi1td, mkkk17, and mkkk18 mutants. We identified 10 novel miRNAs in WT after ABA treatment, while in abi1td, mkkk17, and mkkk18 mutants, three, seven, and nine known miRNAs, respectively, were differentially expressed after ABA treatment. One novel miRNA (miRn-8) was differentially expressed in the mkkk17 mutant. Potential target genes of the miRNA panel were identified using psRNATarget. Sequencing results were validated by quantitative RT-PCR of several known and novel miRNAs in all genotypes. Of the predicted targets of novel miRNAs, seven target genes of six novel miRNAs were further validated by 5′ RLM-RACE. Gene ontology analyses showed the potential target genes of ABA-responsive known and novel miRNAs to be involved in diverse cellular processes in plants, including development and stomatal movement. These outcomes suggest that a number of the identified miRNAs have crucial roles in plant responses to environmental stress, as well as in plant development, and might have common regulatory roles in the core ABA signaling pathway. 相似文献
974.
In the present work, the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes (38mm-O.D.) in a commercial circulating fluidized bed (CFB) boiler. Heat transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246mm. The heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler. A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal approach. The predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale. 相似文献
975.
Ting Meng Wojciech J Florkowski Anna M Klepacka Daniel B Sarpong Anna V A Resurreccion Manjeet S Chinnan Adam Ekielski 《Journal of the science of food and agriculture》2018,98(2):i-i
The cover image, by Ting Meng et al., is based on the Research Article Preferences for groundnut products among urban residents in Ghana, DOI: 10.1002/jsfa.8532 . Photo Credit: Wojciech J Florkowski.
976.
Wojciech Knap Salman Nadar Hadley Videlier Stephane Boubanga-Tombet Dominique Coquillat Nina Dyakonova Frederic Teppe Kristoph Karpierz Jerzy ?usakowski Maciej Sakowicz Irmantas Kasalynas Dalius Seliuta Gintaras Valusis Taiichi Otsuji Yahya Meziani Abdel El Fatimy Simon Vandenbrouk Kamel Madjour Didier Th��ron Christophe Gaqui��re 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(5):618-628
Resonant frequencies of the two-dimensional plasma in field effect transistors (FETs) increase with the reduction of the channel dimensions and can reach the Terahertz (THz) range. Nonlinear properties of the plasma/electron gas in the transistor channel can be used for the rectification and detection of THz radiation. The excitation of plasma waves by sub-THz and THz radiation was demonstrated for short gate transistors at cryogenic temperatures. At room temperature plasma oscillations are usually overdamped, but the FETs can still operate as efficient broadband rectifiers/detectors in the THz range. We present a few recent experimental results on THz detection by FETs showing some new ways of improvement of FETs for THz imaging at room temperature as well as the new physical phenomena like detection in quantizing magnetic fields. We also demonstrate THz emission properties of GaN based FETs. 相似文献
977.
Magdalena Gawęda Piotr Jeleń Elżbieta Długoń Aleksandra Wajda Magdalena Leśniak Wojciech Simka Maciej Sowa Rainer Detsch Aldo R. Boccaccini Maciej Sitarz 《Journal of the American Ceramic Society》2018,101(2):590-601
Black glasses are amorphous materials based on silicon oxycarbide. The use of precursors in the form of ladder‐like silsesquioxanes enables the control of the amount of carbon ions in the glass network by adjusting ratios of T to D structural units in precursors. In this study, four different sols precursors of four different layers of black glasses on titanium substrates were prepared. The materials were analyzed with the use of various spectroscopic and microscopic methods. Formation of continuous and hermetic layers resistant to corrosion was proven. The black glasses layers were examined as materials for biomedical applications. Therefore, preliminary tests of their bioactivity and biocompatibility were performed. The best results were obtained for the material of lower contribution of carbon ions. 相似文献
978.
Cristina Cvitanich Wojciech J. Przyby?owicz Jolanta Mesjasz-Przyby?owiczMatthew W. Blair Carolina AstudilloEl?bieta Or?owska Anna M. JurkiewiczErik Ø. Jensen Jens Stougaard 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(20):2297-2302
This study compares the distribution and concentrations of micro- and macronutrients in different bean cultivars with the aim of optimizing the biofortification, a sustainable approach towards improving dietary quality. Micro-PIXE was used to reveal the distribution of Fe, Zn, Mn, Ca, P, S in seeds of common beans (Phaseolus vulgaris) and runner beans (Phaseolus coccineus). Average concentrations of elements in different tissues were obtained using ICP-AES. The highest concentrations of Zn in the studied beans were found in the embryonic axis, but an increased concentration of this element was also detected in the provascular bundles of the cotyledons. The first layer of cells surrounding provascular bundles accumulated high concentrations of Fe, while the next cell layer had an increased concentration of Mn. The analysis showed that the provascular bundles and the first cell layers surrounding them could have a significant role in the storage of important seed micronutrients - Zn, Fe, and Mn. This information has important implications for molecular biology studies aimed at seed biofortification. 相似文献
979.
Bożena Sartowska Jerzy Piekoszewski Lech Waliś Jan Senatorski Marek Barlak Wojciech Starosta Cezary Pochrybniak Irena Pokorska 《Surface & coatings technology》2011
Austenitic stainless steels are widely used in numerous industrial applications due to their excellent corrosion resistance. However some applications are limited in cases when due to low hardness and poor tribological properties of stainless steel wear is responsible for the durability of a given engineering component.In the present work we have undertaken an attempt to improve the wear resistance of AISI 316L steel by alloying its near surface region with rare earth elements—REE using high intensity pulsed plasma beams in so called deposition by pulse erosion (DPE) mode. Power density of pulses was 106–107 W/cm2 with the pulse duration in μs range. Heating and cooling processes were of non-equilibrium type. The near surface layer—thickness in μm range—was melted and simultaneously doped with cerium and lanthanum. Various parameters of the process were set up to get level of doping between 0.3 and 2.8 at.% REE.An improvement of tribological properties—linear wear and scratch resistance—with increasing REE concentration as compared to the initial material was observed. 相似文献
980.
Magdalena Paczkowska-Walendowska Natalia Rosiak Ewa Tykarska Katarzyna Michalska Anita Paziska Wojciech Paziski Daria Szymanowska Judyta Cielecka-Piontek 《International journal of molecular sciences》2021,22(1)
Progressive increase in bacterial resistance has caused an urgent need to introduce new antibiotics, one of them being oxazolidinones with their representative tedizolid. Despite the broad spectrum of activity of the parent tedizolid, it is characterized by low water solubility, which limits its use. The combination of the active molecule with a multifunctional excipient, which is cyclodextrins, allows preservation of its pharmacological activity and modification of its physicochemical properties. Therefore, the aim of the study was to change the dissolution rate and permeability through the model membrane of tedizolid by formation of solid dispersions with a cyclodextrin. The research included identification of tedizolid-hydroxypropyl-β-cyclodextrin (tedizolid/HP-β-CD) inclusion complex by thermal method (Differential Scanning Colorimetry), spectroscopic methods (powder X-ray diffraction, Fourier-Transform Infrared spectroscopy), and molecular docking. The second part of the research concerned the physicochemical properties (dissolution and permeability) and the biological properties of the system in terms of its microbiological activity. An increase in the dissolution rate was observed in the presence of cyclodextrin, while maintaining a high permeation coefficient and high microbiological activity. The proposed approach is an opportunity to develop drug delivery systems used in the treatment of resistant bacterial infections, in which, in addition to modifying the physicochemical properties caused by cyclodextrin, we observe a favorable change in the pharmacological potential of the bioactives. 相似文献