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PURPOSE: There is considerable morphologic overlap between various entities of high-grade gliomas, and, therefore, a further planning of their optimal treatment is a controversial issue. The aim of this study was molecular stratification of morphologically ambiguous high-grade gliomas composed from small cells. Fluorescence in situ hybridization (FISH) with commercially available probes was used for this purpose. EXPERIMENTAL DESIGN: We analyzed a set of 114 high-grade small-cell gliomas that were difficult to interpret diagnostically because of their distinct cytological origin. FISH assay with locus probes for EGFR, p16, PTEN, and 1p and 19q was done. RESULTS: Morphologically uniform high-grade gliomas composed of small cells varied greatly in terms of molecular features and clinical outcome. Four clinically relevant subsets of patients whose tumors showed distinctly different molecular profiles were identified as follows: (a) 13 patients whose tumors exhibited no discernable molecular alterations (5-year survival rate, 83%); (b) 20 patients whose tumors harbored either 1p/19q codeletion or isolated deletion of 19q unaccompanied by other molecular abnormalities (5-year survival rate, 59%); (c) 35 patients whose tumors showed p16 and/or PTEN deletions unaccompanied by EGFR amplification (5-year survival rate, 8%); and (d) 46 patients whose tumors harbored EGFR amplification (5-year survival rate, 0). CONCLUSIONS: The FISH method provides clinically useful information in the molecular analysis of morphologically ambiguous malignant small-cell gliomas that could potentially enhance the quality of patient care. 相似文献
14.
Alexey D. Sereda Mikhail E. Vlasov Galina S. Koltsova Sergey Y. Morgunov Dmitry A. Kudrjashov Irina P. Sindryakova Olga L. Kolbasova Valentina M. Lyska Andrei Y. Koltsov Sergey P. Zhivoderov Elena Y. Pivova Vladimir M. Baluishev Andrey E. Gogin Denis V. Kolbasov 《Viruses》2022,14(8)
The African swine fever virus (ASFV) is the cause of a recent pandemic that is threatening the global pig industry. The virus infects domestic and wild pigs and manifests with a variety of clinical symptoms, depending on the strain. No commercial vaccine is currently available to protect animals from this virus, but some attenuated and recombinant live vaccine candidates might be effective against the disease. This article describes the immunobiological characteristics of one such candidate—the laboratory-attenuated ASFV strain, Katanga-350—which belongs to genotype I. In this study, we assessed clinical signs and post-mortem changes, the levels of viremia and the presence of viral DNA caused by injection of ASF virus strains Katanga-350, Lisbon-57, and Stavropol 08/01. Intramuscular injection of this strain protected 80% of pigs from a virulent strain of the same genotype and seroimmunotype (Lisbon-57). At least 50% of the surviving pigs received protection from subsequent intramuscular infection with a heterologous (genotype II, seroimmunotype VIII) virulent strain (Stavropol 08/01). Virus-specific antibodies were detectable in serum and saliva samples between 8–78 days after the first inoculation of the Katanga-350 strain (the observational period). The results suggested that this strain could serve as a basis for the development of a recombinant vaccine against ASF viruses belonging to seroimmunotype I. 相似文献
15.
Alexander A. Koryakin Sergey A. Kukushkin Andrey V. Osipov Shukrillo Sh. Sharofidinov Mikhail P. Shcheglov 《Materials》2022,15(18)
In this work, the growth mechanism of aluminum nitride (AlN) epitaxial films by hydride vapor phase epitaxy (HVPE) on silicon carbide (SiC) epitaxial layers grown on silicon (110) substrates is investigated. The peculiarity of this study is that the SiC layers used for the growth of AlN films are synthesized by the method of coordinated substitution of atoms. In this growth method, a part of the silicon atoms in the silicon substrate is replaced with carbon atoms. As a result of atom substitution, the initially smooth Si(110) surface transforms into a SiC surface covered with octahedron-shaped structures having the SiC(111) and SiC() facets. The SiC(111)/() facets forming the angle of 35.3° with the original Si(110) surface act as “substrates” for further growth of semipolar AlN. The structure and morphology of AlN films are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), reflection high-energy electron diffraction (RHEED) and Raman spectroscopy. It is found that the AlN layers are formed by merged hexagonal microcrystals growing in two directions, and the following relation is approximately satisfied for both crystal orientations: AlN()||Si(110). The full-width at half-maximum (FWHM) of the X-ray rocking curve for the AlN() diffraction peak averaged over the sample area is about 20 arcmin. A theoretical model explaining the presence of two orientations of AlN films on hybrid SiC/Si(110) substrates is proposed, and a method for controlling their orientation is presented. 相似文献
16.
Brian Walls Oisín Murtagh Sergey I. Bozhko Andrei Ionov Andrey A. Mazilkin Daragh Mullarkey Ainur Zhussupbekova Dmitry A. Shulyatev Kuanysh Zhussupbekov Nikolai Andreev Nataliya Tabachkova Igor V. Shvets 《Materials》2022,15(21)
The strongly correlated electron material, vanadium dioxide (VO), has seen considerable attention and research application in metal-oxide electronics due to its metal-to-insulator transition close to room temperature. Vacuum annealing a VO(010) single crystal results in Wadsley phases (VO, n > 1) and VO. The resistance changes by a factor of 20 at 342 K, corresponding to the metal-to-insulator phase transition of VO. Macroscopic voltage-current measurements with a probe separation on the millimetre scale result in Joule heating-induced resistive switching at extremely low voltages of under a volt. This can reduce the hysteresis and facilitate low temperature operation of VO devices, of potential benefit for switching speed and device stability. This is correlated to the low resistance of the system at temperatures below the transition. High-resolution transmission electron microscopy measurements reveal a complex structural relationship between VO, VO and VO crystallites. Percolation paths incorporating both VO and metallic VO are revealed, which can reduce the resistance below the transition and result in exceptionally low voltage resistive switching. 相似文献
17.
Maxim Mazurin Angelika Shelestova Dmitry Tsvetkov Vladimir Sereda Ivan Ivanov Dmitry Malyshkin Andrey Zuev 《Materials》2022,15(21)
Hybrid organic–inorganic perovskite halides, and, in particular, their mixed halide solid solutions, belong to a broad class of materials which appear promising for a wide range of potential applications in various optoelectronic devices. However, these materials are notorious for their stability issues, including their sensitivity to atmospheric oxygen and moisture as well as phase separation under illumination. The thermodynamic properties, such as enthalpy, entropy, and Gibbs free energy of mixing, of perovskite halide solid solutions are strongly required to shed some light on their stability. Herein, we report the results of an experimental thermochemical study of the CH3NH3Pb(Cl1−xBrx)3 mixed halides by solution calorimetry. Combining these results with molecular dynamics simulation revealed the complex and irregular shape of the compositional dependence of the mixing enthalpy to be the result of a complex interplay between the local lattice strain, hydrogen bonds, and energetics of these solid solutions. 相似文献
18.
Alexander Grenadyorov Vladimir Oskirko Alexander Zakharov Konstantin Oskomov Andrey Solovyev 《Materials》2022,15(22)
The paper deals with the (Cr1−xAlx)N coating containing 17 to 54 % Al which is deposited on AISI 430 stainless steel stationary substrates by short-pulse high-power dual magnetron sputtering of Al and Cr targets. The Al/Cr ratio in the coating depends on the substrate position relative to magnetrons. It is shown that the higher Al content in the (Cr1−xAlx)N coating improves its hardness from 17 to 28 GPa. Regardless of the Al content, the (Cr1−xAlx)N coating manifests a low wear rate, namely (4.1–7.8) × 10−9 and (3.9–5.3) × 10−7 mm3N−1m−1 in using metallic (100Cr6) and ceramic (Al2O3) counter bodies, respectively. In addition, this coating possesses the friction coefficient 0.4–0.7 and adhesive strength quality HF1 and HF2 indicating good interfacial adhesion according to the Daimler-Benz Rockwell-C adhesion test. 相似文献
19.
Abdel-Monem El-Batahgy Mohamed Raafat Elkousy Ahmed Abd Al-Rahman Andrey Gumenyuk Michael Rethmeier Sergej Gook 《Materials》2022,15(23)
Motivated by the loss of tensile strength in 9%Ni steel arc-welded joints performed using commercially available Ni-based austenitic filler metals, the viability of retaining tensile strength using an experimentally produced matching ferritic filler metal was confirmed. Compared to the austenitic Ni-based filler metal (685 MPa), higher tensile strength in gas metal arc (GMA) welded joints was achieved using a ferritic filler metal (749 MPa) due to its microstructure being similar to the base metal (645 MPa). The microstructure of hard martensite resulted in an impact energy of 71 J (−196 °C), which was two times higher than the specified minimum value of ≥34 J. The tensile and impact strength of the welded joint is affected not only by its microstructure, but also by the degree of its mechanical mismatch depending on the type of filler metal. Welds with a harder microstructure and less mechanical mismatch are important for achieving an adequate combination of tensile strength and notched impact strength. This is achievable with the cost-effective ferritic filler metal. A more desirable combination of mechanical properties is guaranteed by applying low preheating temperature (200 °C), which is a more practicable and economical solution compared to the high post-weld heat treatment (PWHT) temperature (580 °C) suggested by other research. 相似文献
20.
In this work, we describe a novel temperate bacteriophage, Bacillus phage B13. Bacillus-infecting phages are widespread and abundant, though often overlooked including because of their temperate lifestyle. B13 was isolated from its bacterial host via mitomycin C induction. Its host range was determined, and its pH and thermal stability were evaluated. The whole genome of B13 was sequenced and annotated. The genome is 36,864 bp long and contains 53 genes. The tail genes of B13 suggest that the phage has a siphovirus morphotype. It was found both in vitro and in silico that the phage uses the 3′-cos DNA packaging strategy, and the phage genome termini were located. Comparative analyses revealed that B13 has no close relatives and should therefore be assigned to a new viral genus, for which we propose the name Bunatrivirus. 相似文献