Kazan Federal University

About: Kazan Federal University is a education organization based out in Kazan’, Russia. It is known for research contribution in the topics: Population & Chemistry. The organization has 9868 authors who have published 14390 publications receiving 135726 citations. The organization is also known as: Kazan (Volga region) Federal University & Kazan State University.

The mechanism of the dielectric relaxation in water.

Abstract: Although relating to the same system, the interpretations of the water spectra from Raman and Dielectric spectroscopy present independent pictures of the nature of water. We show that in the overlap region of the two methods it is possible to combine these views into a coherent concept of what drives the dynamic features of water. In this work, we develop the idea that the dielectric relaxation in water is driven by the migration of defects through the H-bond network, leading to a Debye-like peak in the lower frequencies. The deviation from the Debye law in the higher sub-THz frequencies is traced to a global fluctuation of the same H-bond network, clearly evident in the Raman Spectra. By incorporating these two views, a mathematical formalism is presented that can aptly explicate the dielectric spectra of liquid water.

Plexciton Dirac points and topological modes

Abstract: Plexcitons are polaritonic modes that result from the strong coupling between excitons and plasmons. Here, we consider plexcitons emerging from the interaction of excitons in an organic molecular layer with surface plasmons in a metallic film. We predict the emergence of Dirac cones in the two-dimensional band-structure of plexcitons due to the inherent alignment of the excitonic transitions in the organic layer. An external magnetic field opens a gap between the Dirac cones if the plexciton system is interfaced with a magneto-optical layer. The resulting energy gap becomes populated with topologically protected one-way modes, which travel at the interface of this plexcitonic system. Our theoretical proposal suggests that plexcitons are a convenient and simple platform for the exploration of exotic phases of matter and for the control of energy flow at the nanoscale.

Three-dimensional culture sensitizes epithelial ovarian cancer cells to EZH2 methyltransferase inhibition.

Abstract: Inhibitors of EZH2 methyltransferase activity have been demonstrated to selectively suppress the growth of diffused large B cell lymphoma (DLBCL) cells with gain-of-function mutations in EZH2, while exhibiting very limited effects on the growth of DLBCL cells with wild-type EZH2. Given that EZH2 is often overexpressed but not mutated in solid tumors, it is important to investigate the determinants of sensitivity of solid tumor cells to EZH2 inhibitors. In the current study, we show that three-dimensional (3D) culture of epithelial ovarian cancer (EOC) cells that overexpress EZH2 sensitizes these cells to EZH2 methyltransferase inhibition. Treatment of EOC cells with GSK343, a specific inhibitor of EZH2 methyltransferase, decreases the level of H3K27Me3, the product of EZH2’s enzymatic activity. However, GSK343 exhibited limited effects on the growth of EOC cells in conventional two-dimensional (2D) culture. In contrast, GSK343 significantly suppressed the growth of EOC cells cultured in 3D matrigel extrac...

Secretome of Intestinal Bacilli: A Natural Guard against Pathologies.

Abstract: Current studies of human gut microbiome usually do not consider the special functional role of transient microbiota, although some of its members remain in the host for a long time and produce broad spectrum of biologically active substances. Getting into the gastrointestinal tract (GIT) with food, water and probiotic preparations, two representatives of Bacilli class, genera Bacillus and Lactobacillus, colonize epithelium blurring the boundaries between resident and transient microbiota. Despite their minor proportion in the microbiome composition, these bacteria can significantly affect both the intestinal microbiota and the entire body thanks to a wide range of secreted compounds. Recently, insufficiency and limitations of pure genome-based analysis of gut microbiota became known. Thus, the need for intense functional studies is evident. This review aims to characterize the Bacillus and Lactobacillus in GIT, as well as the functional roles of the components released by these members of microbial intestinal community. Complex of their secreted compounds is referred by us as the “bacillary secretome”. The composition of the bacillary secretome, its biological effects in GIT and role in counteraction to infectious diseases and oncological pathologies in human organism is the subject of the review.

Tubule Nanoclay-Organic Heterostructures for Biomedical Applications.

Abstract: Natural halloysite nanotubes (HNTs) show unique hollow structure, high aspect ratio and adsorption ability, good biocompatibility, and low toxicity, which allow for various biomedical applications in the diagnosis and treatment of diseases. Here, advances in self-assembly of halloysite for cell capturing and bacterial proliferation, coating on biological surfaces and related drug delivery, bone regeneration, bioscaffolds, and cell labeling are summarized. The in vivo toxicity of these clay nanotubes is discussed. Halloysite allows for 10-20% drug loading and can extend the delivery time to 10-100 h. These drug-loaded nanotubes are doped into the polymer scaffolds to release the loaded drugs. The rough surfaces fabricated by self-assembly of the clay nanotubes enhance the interactions with tumor cells, and the cell capture efficacy is significantly improved. Since halloysite has no toxicity toward microorganisms, the bacteria composed within these nanotubes can be explored in oil/water emulsion for petroleum spilling bioremediation. Coating of living cells with halloysite can control the cell growth and is not harmful to their viability. Quantum dots immobilized on halloysite were employed for cell labeling and imaging. The concluding academic results combined with the abundant availability of these natural nanotubes promise halloysite applications in personal healthcare and environmental remediation.