Formation of biofilms by clinical strains of microorganisms responsible for surgical pyoinflammatory diseases in children

The ability of microorganisms to exist in the form of biofilms creates considerable difficulties for medical practice, since in this case the resistance of bacteria to antimicrobial agents is greatly increased. Therefore, the purpose of this study was to scrutinize the ability to form biofilms by microorganisms isolated from children with pyoinflammatory processes. The identification of microorganisms was carried out according to the generally accepted microbiological protocols of their isolation and cultivation. Testing of isolates for the ability to form biofilms was realized by measurement of optical density in standard units (absorbance units - AU) on the spectrophotometer «Multiskan EX 355». The statistical processing of the results was performed using the programs «Statistica 6» and «Biostat». In the course of the study, S. aureus, S.epidermidis, P. aeruginosa, E. coli, Klebsiella, Proteus spp., and C.albicans were isolated. In most cases, microbial associations comprising from two to three types of microorganisms were detected, namely E. coli, K.pneumoniae, S. aureus in 26,8 %; P.vulgaris, Enterobacter, S.epidermidis – 7,9 %; P.mirabilis, K.pneumoniae, C.albicans – 13,4 %; S.aureus, K.pneumoniae, C.albicans – 23,7 %; E.coli, K.pneumoniae, C.albicans – 16,5 %; S. aureus, P. aeruginosa, C.albicans - 3,4 %; E.coli, S.epidermidis, C.albicans – 2,9 %; P. vulgaris, P. aeruginosa, S.epidermidis – 2,8 %; S. aureus, P.mirabilis – 2,6 % of cases. The obtained results indicated the prevalence of microorganisms of the Enterobacteriaceae in children with pyoinflammatory processes in the material examined. The studies of the ability of clinical strains of microorganisms to form daily compound biofilms, as well as plankton cells and new biofilms, made it possible to establish that the maximum daily biofilms density and the highest plankton cell formation were registered in microbial associations of S. aureus, K.pneumoniae, C .albicans (4,56 ± 0,19 AU) and S. aureus, P. aeruginosa, C. albicans (4,87 ± 0,14 AU). Plankton cells of all investigated microorganisms formed secondary biofilms actively with the highest density in C. albicans (3,62 ± 0,16 AU), K.pneumoniae (2,96 ± 0,14 units), S. aureus (3,09 ± 0,18AU) and P. aeruginosa (3,11 ± 0,12 AU). Thus, as a result of the division of bacterial cells, biofilm-forming microorganisms produce plankton cells capable of attaching themselves to the mucous membranes, wounds, catheters, and IV-lines with following formation of the new colonies, subsequently transforming into dense secondary biofilms, which makes for the spread and formation of multiresistant clinical strains of microorganisms. These properties of virulent microorganisms prompt to the development of methods for destruction of biofilms and intensification of micriflora inactivation in the focus of inflammation. Our studies showed that the above mentioned requirements relating to the effective influence on biofilms corresponded to the joint effect of ultrasound and ozone, which significantly increased the efficiency of the treatment complex

Experimental access to Transition Distribution Amplitudes with the P̄ANDA experiment at FAIR

Baryon-to-meson Transition Distribution Amplitudes (TDAs) encoding valuable new information on hadron structure appear as building blocks in the collinear factorized description for several types of hard exclusive reactions. In this paper, we address the possibility of accessing nucleon-to-pion (\u3c0N) TDAs from \uafpp \u2192 e+e 12\u3c00 reaction with the future PANDA detector at the FAIR facility. At high center- of-mass energy and high invariant mass squared of the lepton pair q2, the amplitude of the signal channel pp\uaf \u2192 e+e 12\u3c00 admits a QCD factorized description in terms of \u3c0N TDAs and nucleon Distribution Amplitudes (DAs) in the forward and backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring \uafpp \u2192 e+e 12\u3c00 with the PANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. pp\uaf \u2192 \u3c0+\u3c0 12\u3c00 were performed for the center-of-mass energy squared s = 5 GeV2 and s = 10 GeV2, in the kinematic regions 3.0 0.5 in the proton-antiproton center-of-mass frame. Results of the simulation show that the particle identification capabilities of the PANDA detector will allow to achieve a background rejection factor of 5 \ub7 107 (1 \ub7 107) at low (high) q2 for s = 5 GeV2, and of 1 \ub7 108 (6 \ub7 106) at low (high) q2 for s = 10 GeV2, while keeping the signal reconstruction efficiency at around 40%. At both energies, a clean lepton signal can be reconstructed with the expected statistics corresponding to 2 fb 121 of integrated luminosity. The cross sections obtained from the simulations are used to show that a test of QCD collinear factorization can be done at the lowest order by measuring scaling laws and angular distributions. The future measurement of the signal channel cross section with PANDA will provide a new test of the perturbative QCD description of a novel class of hard exclusive reactions and will open the possibility of experimentally accessing \u3c0N TDAs

Eperimental access to Transition Distribution Amplitudes with the PANDA experiment at FAIR

We address the possibility of accessing nucleon-to-pion (πN) Transition Distribution Amplitudes (TDAs) from p¯p→e+e−π0 reaction with the future \={P}ANDA detector at the FAIR facility. At high center of mass energy and high invariant mass of the lepton pair q2, the amplitude of the signal channel p¯p→e+e−π0 admits a QCD factorized description in terms of πN TDAs and nucleon Distribution Amplitudes (DAs) in the forward and backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring p¯p→e+e−π0 with the \={P}ANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, {\it i.e.} p¯p→π+π−π0 were performed for the center of mass energy squared s=5 GeV2 and s=10 GeV2, in the kinematic regions 3.00.5 in the proton-antiproton center of mass frame. Results of the simulation show that the particle identification capabilities of the \={P}ANDA detector will allow to achieve a background rejection factor at the level of 108 (2⋅107) at low (high) q2 while keeping the signal reconstruction efficiency at around 40% and that a clean lepton signal can be reconstructed with the expected statistics corresponding to 2 fb−1 of integrated luminosity. The future measurement of the signal channel cross section with \={P}ANDA will provide a new test of perturbative QCD description of a novel class of hard exclusive reactions and will open the possibility of experimentally accessing πN TDAs