Azithromycin possesses biofilm–inhibitory activity and potentiates non-bactericidal colistin methanesulfonate (CMS) and polymyxin B against <i>Klebsiella pneumonia</i>

Novel antibiotic combinations may act synergistically to inhibit the growth of multidrug-resistant bacterial pathogens but predicting which combination will be successful is difficult, and standard antimicrobial susceptibility testing may not identify important physiological differences between planktonic free-swimming and biofilm-protected surface-attached sessile cells. Using a nominally macrolide-resistant model Klebsiella pneumoniae strain (ATCC 10031) we demonstrate the effectiveness of several macrolides in inhibiting biofilm growth in multi-well plates, and the ability of azithromycin (AZM) to improve the effectiveness of the antibacterial last-agent-of-choice for K. pneumoniae infections, colistin methanesulfonate (CMS), against biofilms. This synergistic action was also seen in biofilm tests of several K. pneumoniae hospital isolates and could also be identified in polymyxin B disc-diffusion assays on azithromycin plates. Our work highlights the complexity of antimicrobial-resistance in bacterial pathogens and the need to test antibiotics with biofilm models where potential synergies might provide new therapeutic opportunities not seen in liquid culture or colony-based assays

Thomson scattering diagnostics at the Globus M2 tokamak

The paper is devoted to the Thomson scattering (TS) diagnostics recently developed for the Globus-M2 spherical tokamak and prototyping the ITER divertor TS diagnostics. The distinctive features of the system are the use of spectrometers, acquisition system and lasers that meet the base requirements for ITER TS diagnostics. The paper describes the diagnostic system that allows precise measurements of TS signals, as well as the results of the first measurements of electron temperature and density in both central region of the plasma column and scrape-off layer. The system provides measurements of electron temperature $T_{e}$ in the range of 5 eV to 5 keV and density $n_{e}$ in the range of $5{\cdot}10^{17}{\div}3.25{\cdot}10^{20} m^{-3}$. The use of two ITER-grade probing lasers of different wavelengths (Nd:YAG 1064.5 nm and Nd:YLF 1047.3 nm) allows reliable measurement of $T_{e}$ in multi-colour mode, i.e., assuming that spectral calibration is unknown

BRAIN NATRIURETIC PEPTIDE AS BIOCHEMICAL MARKER FOR STRUCTURAL AND FUNCTIONAL HEART DISORDERS IN ARTERIAL HYPERTENSION

Aim. Assessment of structural and functional condition of the left and right heart chambers related to the level of NT-proBNP and clinical signs of CHD in AH patients.Material and methods. Totally, 137 AH patients studied (45 men, 92 women) with sinus rhythm and EF LV ≥50%. All patients underwent standard investigations, 6-minute walking test, two-dimension EchoCG, transvalvular and tissue Dopplergraphy, treadmill-test, NT-proBNP concentration in plasma. Assessment of structural and functional heart condition was done in three defined groups according to NT-proBNP level (norm, “grey” zone, elevated NT-proBNP).Results. The level of NT-proBNP is related to the age, sex, therapy intake regularity and does not relate to body mass, BP level, heart rate. The relation revealed for NTproBNP level and diastolic dysfunction of the LV by the data of transmitral and tissue Doppler-graphy. Modified Tei index, obtained during impulse-wave tissue Dopplergraphy, was the most informative marker of LV dysfunction, relevant of NT-proBNP levels. The increase of NT-proBNP followed by significant increase of RV wall thickness. Evaluation of NT-proBNP together with EchoCG led to revelation of asympthomatic LV dysfunction in 13,1% of patients.Conclusion. Interpretation of NT-proBNP level in hypertensive must complex, taking into consideration clinical factors as risk factors, gender and age. Evaluation of NT-proBNP with echocardiography helps to identify groups of patients of higher cardiovascular risk and to optimize further treatment

CHEMOTHERAPY CARDIOTOXICITY SCREENING WITH CARDIAC TROPONINS

Recently, chemotherapy is one of the most trustworthy methods for treatment of malignant tumors and blood pathology. However clinical effect of the drugs not always matches with safety. These facts play as a solid evidence for the necessity of studying the problems related to side effects of the drugs, and, particularly, of cardiotoxicity, as reversible and/or irreversible damage of cardiomyocytes. Currently, the most sensitive ad specific markers of myocardium cells are troponins T and I. According with this, the main aims of this article are analysis of literary data for the problem of cardiac troponins application as cardiotoxicity revealing in oncology patients, and summon of more attention to this direction of science. The article provides a collection of the key points of all available studies at the moment, shows generalized analysis, analyses also the Russian and European Guidelines from the point of view related to troponins tests in oncology patients

Therapeutic Potential of an Azithromycin-Colistin Combination against XDR <i>K. pneumoniae</i> in a 3D Collagen-Based In Vitro Wound Model of a Biofilm Infection

A therapeutic combination of azithromycin (AZM) and colistin methanesulfonate (CMS) was shown to be effective against both non-PDR and PDR Klebsiella pneumoniae biofilms in vitro. These anti-biofilm effects, however, may not correlate with effects observed in standard plate assays, nor will they representative of in vivo therapeutic action. After all, biofilm-associated infection processes are also impacted by the presence of wound bed components, such as host cells or wound fluids, which can all affect the antibiotic effectiveness. Therefore, an in vitro wound model of biofilm infection which partially mimics the complex microenvironment of infected wounds was developed to investigate the therapeutic potential of an AZM-CMS combination against XDR K. pneumoniae isolates. The model consists of a 3D collagen sponge-like scaffold seeded with HEK293 cells submerged in a fluid milieu mimicking the wound bed exudate. Media that were tested were all based on different strengths of Dulbecco’s modified Eagles/high glucose medium supplemented with fetal bovine serum, and/or Bacto Proteose peptone. Use of this model confirmed AZM to be a highly effective antibiofilm component, when applied alone or in combination with CMS, whereas CMS alone had little antibacterial effectiveness or even stimulated biofilm development. The wound model proposed here proves therefore, to be an effective aid in the study of drug combinations under realistic conditions

Confinement bifurcation by magnetic compression on TUMAN-3

INTRODUCTION Experiments on magnetic compression on different tokamaks have shown superadiabatic increases in the plasma parameters On TUMAN-3 the both enhancement and degradation of the confinement were observed in the minor radius magnetic compression experiments In this paper the results of the new study of the L-H transition triggered by magnetic compression are presented. The feature of the recent experiments was small compression ratio what allowed reducing power input P ∂B/∂t during compression phase. The mechanism of the radial electric field E r origin during magnetic compression is proposed to account for the L-H transition