[Role of epithelial-mesenchymal transition in the pathogenesis of dermal wound healing]

Background. Investigation of mechanisms of wound healing remains relevant. It remains unknown the role of epithelial to mesenchymal transition in the regeneration. Epithelial to mesenchymal transition is a fundamental process, that leads epithelial cells to lose their polarization and specialized junctional structures, to undergo cytoskeleton reorganization, and to acquire morphological and functional features of mesenchymal-like cells. Epithelial to mesenchymal transition has been originally described in embryonic development, regeneration and several pathophysiological conditions. Objective is to investigate the role of epithelial to mesenchymal transition in wound healing. Results. The key points in the implementation mechanisms of epithelial to mesenchymal transition are described. The initiating role of growth factors and signaling pathways, participates in the development of epithelial to mesenchymal transition, are indicated. The comparative characteristic of incomplete epithelial to mesenchymal transition in the wound healing and completed epithelial to mesenchymal transition during pathological processes are given. Such kinds of epithelial to mesenchymal transition as endothelial-mesenchymal transition and back-mesenchymal to epithelial transition and their role in the wound healing process are enlightened. Conclusion. Epithelial to mesenchymal transition is a fundamental mechanism of histogenesis and tissue regeneration. Understanding the epithelial to mesenchymal transition and the factors involved in will help to create a theoretical framework for the development of new approaches to rational therapy of wound healing. Citation: Volkov KS, Kramar SB. [Role of epithelial-mesenchymal transition in the pathogenesis of dermal wound healing]. Morphologia. 2015;9(2):7-10. Russian

Histophysiology of submandibular salivary glands end pieces in rats with chronic ethanol intoxication

В роботі представлені дані морфометричного дослідження паренхіми піднижньощелепної слинної залози при хронічній інтоксикації етанолом. Встановлено, що хронічна інтоксикація етанолом впливає на морфофункціональний стан кінцевих відділів часточок піднижньощелепної залози щурів, що підтверджується зменшенням діаметру просвіту та збільшенням висоти епітеліоцитів до 15,44±0,41мкм на ранніх стадіях спостереження. Зменшенням діаметру зовнішнього та діаметру просвіту із зменшенням висоти епітеліоцитів на тридцяту добу експерименту. Що обумовлене дистрофічними змінами в клітинах кінцевих відділів піднижньощелепних залоз щурів на пізніх стадіях експерименту, та підтверджується зменшенням їх розмірів, кількості секреторних гранул та підвищенням оптичної щільності клітин. The paper presents the morphometric study of the submandibular salivary gland parenchyma in chronic intoxication with ethanol. It has been established, that chronic ethanol intoxication affects the morphofunctional state of the submandibular gland lobules’ end pieces in rats, which is confirmed by the lumen diameter reduction and the epithelial cells height growth up to 15.44 ± 0.41 µm at the early stages of observation. Reduction in the external diameter and the lumen diameter with the reduced epithelial cells height were observed on the thirtieth day of the experiment. This is due to dystrophic changes in the cells of the of the submandibular glands end pieces in rats at the later stages of the experiment, and is confirmed by reduction in their size, the number of secretory granules and the increased optical density of cells

Synthesis of Mn2+-doped CdS nanoparticles covered with different adsorptive layers and their application as biosensors

Colloidal CdS:Mn nanoparticles were synthesized in water solutions of the polymer polyvinyl-pyrrolidone (PVP), the surfactant cetyl-trimethyl-ammonium bromide (CTAB) and the mixture of PVP and CTAB. The sizes of nanoparticles were determined by electron microscopy and optical absorption methods. The growth media influence on photoluminescence of nanoparticles has been studied. It has been shown that the chemical composition and structure of the adsorptive layer on the surface of nanoparticles can be used as a technological tool to control their light emission. The possibility to use CdS:Mn NPs grown in PVP as light-emitting labels in biological media has been demonstrated

Gravity, p-branes and a spacetime counterpart of the Higgs effect

We point out that the worldvolume coordinate functions $\hat{x}^\mu(\xi)$ of a $p$-brane, treated as an independent object interacting with dynamical gravity, are Goldstone fields for spacetime diffeomorphisms gauge symmetry. The presence of this gauge invariance is exhibited by its associated Noether identity, which expresses that the source equations follow from the gravitational equations. We discuss the spacetime counterpart of the Higgs effect and show that a $p$-brane does not carry any local degrees of freedom, extending early known general relativity features. Our considerations are also relevant for brane world scenarios.Comment: 5 pages, RevTeX. v2 (30-IV-03) with additional text and reference

Dirac equation for the supermembrane in a background with fluxes from a component description of the D=11 supergravity-supermembrane interacting system

We present a simple derivation of the 'Dirac' equation for the supermembrane fermionic field in a D=11 supergravity background with fluxes by using a complete but gauge-fixed description of the supergravity-supermembrane interacting system previously developed. We also discuss the contributions linear in the supermembrane fermions -the Goldstone fields for the local supersymmetry spontaneously broken by the superbrane- to the field equations of the supergravity-supermembrane interacting system. The approach could also be applied to more complicated dynamical systems such as those involving the M5-brane and the D=10 Dirichlet branes.Comment: 1+22 pages, JHEP style. v2: cosmetic changes and references added to conform to the JHEP published versio

Synthesis of Mn²⁺-doped CdS nanoparticles covered with different adsorptive layers and their application as biosensors

Colloidal CdS:Mn nanoparticles were synthesized in water solutions of the polymer polyvinyl-pyrrolidone (PVP), the surfactant cetyl-trimethyl-ammonium bromide (CTAB) and the mixture of PVP and CTAB. The sizes of nanoparticles were determined by electron microscopy and optical absorption methods. The growth media influence on photoluminescence of nanoparticles has been studied. It has been shown that the chemical composition and structure of the adsorptive layer on the surface of nanoparticles can be used as a technological tool to control their light emission. The possibility to use CdS:Mn NPs grown in PVP as light-emitting labels in biological media has been demonstrated

Reflection, radiation and interference for black holes

Black holes are capable of reflection: there is a finite probability for any particle that approaches the event horizon to bounce back. The albedo of the black hole depends on its temperature and the energy of the incoming particle. The reflection shares its physical origins with the Hawking process of radiation, both of them arise as consequences of the mixing of the incoming and outgoing waves that takes place on the event horizon.Comment: 10 pages, 1 figure, Revte

No hair for spherical black holes: charged and nonminimally coupled scalar field with self--interaction

We prove three theorems in general relativity which rule out classical scalar hair of static, spherically symmetric, possibly electrically charged black holes. We first generalize Bekenstein's no--hair theorem for a multiplet of minimally coupled real scalar fields with not necessarily quadratic action to the case of a charged black hole. We then use a conformal map of the geometry to convert the problem of a charged (or neutral) black hole with hair in the form of a neutral self--interacting scalar field nonminimally coupled to gravity to the preceding problem, thus establishing a no--hair theorem for the cases with nonminimal coupling parameter $\xi<0$ or $\xi\geq {1\over 2}$. The proof also makes use of a causality requirement on the field configuration. Finally, from the required behavior of the fields at the horizon and infinity we exclude hair of a charged black hole in the form of a charged self--interacting scalar field nonminimally coupled to gravity for any $\xi$.Comment: 30 pages, RevTeX. Sec.IV corrected, simplified and shortened. Corrections to Sec.IIA between Eqs. 2.7 and Eq.2.1. First two paragraphs of Sec. VC new. To appear Phys. Rev. D, Oct. 15, 199

Faraday rotation in graphene

We study magneto--optical properties of monolayer graphene by means of quantum field theory methods in the framework of the Dirac model. We reveal a good agreement between the Dirac model and a recent experiment on giant Faraday rotation in cyclotron resonance. We also predict other regimes when the effects are well pronounced. The general dependence of the Faraday rotation and absorption on various parameters of samples is revealed both for suspended and epitaxial graphene.Comment: 10 pp; v2: typos corrected and references added, v3, v4: small changes and more reference

Rare Charm Decays in the Standard Model and Beyond

We perform a comprehensive study of a number of rare charm decays, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects. For processes mediated by the $c\to u\ell^+\ell^-$ transitions, we show that sensitivity to short distance physics exists in kinematic regions away from the vector meson resonances that dominate the total rate. In particular, we find that $D\to\pi\ell^+\ell^-$ and $D\to\rho\ell^+\ell^-$ are sensitive to non-universal soft-breaking effects in the Minimal Supersymmetric Standard Model with R-parity conservation. We separately study the sensitivity of these modes to R-parity violating effects and derive new bounds on R-parity violating couplings. We also obtain predictions for these decays within extensions of the Standard Model, including extensions of the Higgs, gauge and fermion sectors, as well as models of dynamical electroweak symmetry breaking.Comment: 45 pages, typos fixed, discussions adde