Enabling magnetic resonance imaging of hollow-core microstructured optical fibers via nanocomposite coating

Optical fibers are widely used in bioimaging systems as flexible endoscopes capable of low-invasive penetration inside hollow tissue cavities. Here, we report on the technique which allows magnetic resonance imaging (MRI) of hollow-core microstructured fibers (HC-MFs), paving the way for combing MRI and optical bioimaging. Our approach is based on Layer-by-Layer assembly of oppositely charged polyelectrolytes and magnetite nanoparticles on the inner core surface of HC-MFs. Incorporation of magnetite nanoparticles into polyelectrolyte layers renders HC-MFs visible for MRI and induces the red-shift in their transmission spectra. Specifically, the transmission shifts up to 60 nm have been revealed for the several-layers composite coating along with the high-quality contrast of HC-MFs in MRI scans. Our results shed light on marrying fiber-based endoscopy with MRI that opens novel possibilities for minimally invasive clinical diagnostics and surgical procedures in vivo.Comment: 11 pages, 6 figure

Boosting the Power Generation in Wind and Hydro Power Production

When approaching a conventional wind turbine, the air flow is slowed down and widened. This results in a loss of turbine efficiency. In order to exploit wind or water flow power as effectively as possible, it was suggested that the turbine should be placed inside a shroud, which consists of 4 wing-shaped surfaces. Two internal air foils improve the turbine performance by speeding up the flow acting on the turbine blades, two external wings create a field of low pressure behind the turbine, thus, helping to draw more mass flow to the turbine and avoid the loss of efficiency due to flow deceleration. The system accumulates kinetic energy of the flow in a small volume where the smaller (and therefore, cheaper) turbine can be installed. A smaller system can be installed inside the bigger one, which would help to accumulate even more kinetic energy on the turbine. This method implies kinetic energy summation with local flow redistribution. Both experiments and CFD simulations demonstrate a significant increase in velocity and generated mechanical power in comparison to those for a bare turbine

CXCR3 chemokine receptor ligands in sarcoidosis

Sarcoidosis is a polysystemic inflammatory disease of unknown etiology, morphologically related to the group of granulomatosis, with heterogeneous clinical manifestations and outcomes. Immune cells, in particular T helper cells, are attracted to lung tissue and/or other organs by chemokine gradients and play an important role in the granuloma formation. T helper cells migrate from peripheral blood to the tissues due to expression of CXCR3 chemokine receptor on their surface. It interacts, e.g., with CXCL9/MIG, CXCL10/IP- 10, and CXCL11/I-TAC. Our study was aimed for determining the levels of CXCL9/MIG, CXCL10/IP-10, CXCL11/I-TAC chemokines in peripheral blood of the patients with sarcoidosis, depending on the features of their clinical course before administration of immunosuppressive therapy. We studied peripheral blood plasma samples of the patients with sarcoidosis (n = 52). In 37% (19/52), they exhibited acute clinical manifestations, and 63% (33/52) had chronic sarcoidosis. The control group included peripheral blood samples from healthy volunteers (n = 22). The chemokine concentrations (pg/ml) were determined by multiplex analysis using xMAP technology (Luminex), and Milliplex MAP test system (Millipore, USA). In the patients with sarcoidosis, significantly higher levels of chemokines were shown relative to healthy volunteers: CXCL9, 4013.00 pg/ml vs 1142.00 pg/ml (p < 0.001); CXCL10, 565.90 pg/ml vs 196.60 pg/ml (p < 0.001); CXCL11, 230.20 pg/ml vs 121.10 pg/ml (p = 0.018). Plasma concentrations of CXCL9 and CXCL10 were significantly increased both in blood samples from patients with acute and chronic sarcoidosis compared to healthy volunteers, p < 0.001. The level of CXCL11 chemokine was significantly increased only in the patients with chronic sarcoidosis, compared to the healthy volunteers: respectively, 251.50 pg/ml and 121.10 pg/ml (p = 0.044). The levels of this chemokine correlated with the activity of angiotensin-converting enzyme (ACE), with r = 0.374; p = 0.042. The ACE level in sarcoidosis is considered a clinical and laboratory index of the disease activity. In acute sarcoidosis, the level of CXCL11 chemokine was not significantly higher than in healthy individuals, whereas the CXCL9 chemokine content was significantly increased and correlated with ACE activity (r = 0.762; p = 0.037). The level of CXCL9 chemokine was significantly decreased in patients with signs of fibrosis as compared with fibrosis-free patients (1839.88 pg/ml vs 4375.52 pg/ml, p = 0.035). Significantly higher levels of CXCL9 were detected in cases of systemic sarcoidosis, i.e. 6036.84 pg/ml, as compared with 1927.44 pg/ml in the patients without these signs (p = 0.018). Evaluation of clinical and laboratory diagnostic characteristics for plasma chemokine levels in sarcoidosis patients allowed to assess their sensitivity and specificity. The respective values were as follows: in acute sarcoidosis: for CXCL9, 84% and 95%; for CXCL10, 84% and 95%; for CXCL11, 74% and 59%. In chronic sarcoidosis, the respective values for CXCL9 were 82% and 72%; for CXCL10, 91% and 77%; for CXCL11, 79% and 55%, respectively. Thus, the determination of plasma CXCL9, CXCL10, and CXCL11 chemokines in sarcoidosis allows of understanding their role in development of the disease, e.g., recruitment of T helper cells from peripheral blood to the lung tissue, and granuloma formation. Clinical and immunological comparisons of CXCL9 levels in the peripheral blood of patients and characteristics of the clinical course of sarcoidosis indicate to the role of this diagnostic parameter for assessing the disease activity, signs of lung fibrosis, and systemic manifestations in this disease

Features of cytokine profile in patients with sarcoidosis

Sarcoidosis is an inflammatory disease of unknown etiology with damage to the lungs and other organs characterized by development of necrosis-free epithelioid cell granulomas. Granulomatous inflammation characterized by the activation of different immune systems cells, in particular T lymphocytes, and the cytokines production. Our study was aimed at investigating the characteristics of the cytokine profile of blood plasma in patients with sarcoidosis. We studied peripheral blood plasma samples of patients with sarcoidosis (n = 52). The control blood samples were taken from healthy volunteers (n = 22). The level of 46 cytokines (pg/ml) was determined, as follows: IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL- 6, IL-7, IL-9, IL-12 (p40), IL-12 (p70), IL-13, IL-15, IL-17A, IFNα2, IFNγ, TNFα, TNFβ, IL- 1ra, IL-10, EGF, FGF-2, Flt3 Ligand, G-CSF, GM-CSF, PDGF-AA, PDGF-AB / BB, TGFα, VEGF-A, sCD40L, CCL2, CCL3, CCL4, CCL5, CCL7, CCL11, CCL17, CCL20, CCL22, CXCL1, CXCL8, CXCL9, CXCL10, CXCL11, CXCL13, CX3CL1. Significantly higher levels of interleukins and some proinflammatory cytokines were found in the patients with sarcoidosis, i.e., IL-3, 0.70 vs 0.20, p = 0.003; IL-4, 14.37 vs 3.15, p = 0.009; IL-5, 1.06 vs 0.89, p < 0.001; IL-12 (p70), 1.27 vs 0.56, p = 0.028; IL-17A, 1.48 vs 0.43, p < 0.001; IFNα2, 41.79 vs 25.04, p = 0.003; IFNγ, 4.13 vs 1.14, p < 0.001; TNFα, 21.67 vs 6.70, p < 0.001; anti-inflammatory cytokine IL-10, 1.03 vs 0.45, p = 0.019; growth factors: FGF-2, 40.08 vs 30.58, p = 0.008, G-CSF, 24.18 vs 8.21, p = 0.006, and VEGF-A, 42.52 vs 26.76, p = 0.048; chemokines: CCL3, 3.86 vs 1.33, p < 0,001; CCL17, 78.24 vs 26.24, p < 0.001; CCL20, 7.19 vs 5.64, p = 0.021; CCL22, 660.60 vs 405.00, p < 0,001; CXCL9, 4013 vs 1142, p < 0,001; CXCL10, 565.90 vs 196.60, p < 0.001; CXCL11, 230.20 vs 121.10, p = 0.018; CX3CL1, 56.99 vs 5.16, p < 0.001. Peripheral blood chemokine CCL11 levels were significantly lower in patients compared to the group of healthy volunteers: 77.58 vs 124.70, p = 0.022. The features of the cytokine profile in patients with sarcoidosis may indicate their important role in the processes of formation and outcomes of granulomas. These issues require an additional detailed study, comparison with phenotypes, differential course and outcomes of the disease

Collection of microorganisms of ICG SB RAS as a genetic resource for biotechnology

Genetic knowledge of microorganisms plays a critical role in the creation of new biotechnologies, since the effectiveness of any biotechnology is determined by the particular qualities of the structurally functional organization of molecular-genetic systems and their components used for the production of targeted products. Collections of microbial cultures play a decisive role in mobilizing biological resources and make it possible to form a solid base for genetic, molecular biological and biotechnological research. The aim of this work was to assess the key molecular-genetic and phenotypic characteristics of strains of the collection of microorganisms created in the “FRC Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences” as a genetic resource for biotechnology. Thirty strains of microorganisms of the collection were isolated by employees of the FRC ICG SB RAS from extreme natural ecosystems, the key molecular-genetic and phenotypic characteristics were described using modern methods of molecular biology and mass-spectrometry. DNA isolation and the sequencing of 16S rRNA gene sequences were performed. The strains of the collection were characterized by morphological, physiological, moleculargenetic and mass-spectrometric characteristics. The particular qualities of growing of strains on different substrates have been established, the study of cell morphology has been carried out. The physiological characteristics of the strains of the collection have been established: the attitude to oxygen, the type of nutrition, the range of temperature and pH, the attitude to NaCl and others. Different resistance of strains to antibiotics has been established. The creation of personal mass spectra of protein profiles of the studied strains of the collection was carried out. The resulting DNA sequences of the strains are deposited in the GenBank. The chemotaxonomic characteristics of strains have been determined. The biotechnological properties of the strains were assessed, the amount of metabolites (ethanol, lactic and acetic acids) in the culture liquid was determined. The value of the collection of microorganisms of the FRC ICG SB RAS as a genetic resource for biotechnology and bioengineering is determined not only by the species diversity of its strains, but also by a wide range of their area isolation and by the depth of their characterization using the widest arsenal of both classical and modern methods (including methods of genomics, proteomics, transcriptomics and bioinformatics)

CHEMOKINES CCL17 AND CCL22 IN SARCOIDOSIS

Various immune cells as well as related cytokines are involved in immunopathogenesis of sarcoidosis and mechanisms of granuloma development. Currently, a role for chemokines in sarcoidosis has been extensively investigated, which is paralleled with a search for key molecules necessary for recruiting immune cells to intrusion site and granuloma formation as well as affecting outcome of the latter. Our study was aimed for determining level of plasma CCL17/TARC and CCL22/MDC chemokines in patients with sarcoidosis who received no immunosuppressive therapy is of high priority for clarifying some aspects in underlying immunopathogenesis as well as seeking out for secure clinical and laboratory criteria for assessing activity and disease prognosis. We studied peripheral blood plasma samples of the patients with sarcoidosis (n = 52). In 37% (19/52), they exhibited acute clinical manifestations, and 63% (33/52) had chronic sarcoidosis. The control group included peripheral blood samples from healthy volunteers (n = 22). The chemokine concentrations (pg/ml) were determined by multiplex analysis using xMAP technology (Luminex), and Milliplex MAP test system (Millipore, USA). In the patients with sarcoidosis, significantly higher levels of chemokines were shown relative to healthy volunteers: CCL17 – 78.24 pg/ml vs 26.24 pg/ml, p < 0.001; CCL22 – 660.60 pg/ml vs 405.00 pg/ml, p < 0.001. Evaluation of clinical and laboratory diagnostic characteristics for plasma chemokine levels in sarcoidosis patients allowed to assess their sensitivity and specificity. The respective values were as follows: in acute sarcoidosis: for CCL17 – 63% and 78%, CCL22 – 63% and 91%; in chronic sarcoidosis: CCL17 – 58% and 83%, CCL22 – 67% and 86%, respectively. In chronic sarcoidosis the levels of this chemokine correlated with the activity of angiotensin-converting enzyme (ACE), for CCL17 (r = 0.530; p = 0.003), for CCL22 (r = 0.446; p = 0.014). Patients with systemic lesions vs no systemic lesions (sarcoidosis of the respiratory system only) had significantly elevated CCL17 level: 102.82 pg/ml vs 32.72 pg/ml, p = 0.011. The concentration of chemokine CCL17 was significantly increased in patients with vs without signs of hepatomegaly: 130.73 pg/ml vs 51.60 pg/ml, p = 0.022. Levels of chemokines was significantly increased in patients with vs without ultrasound signs of splenomegaly comprising: for CCL17 – 249.18 pg/ml vs 46.87 pg/ml, p = 0.002; for CCL22 – 1271.40 pg/ml vs 660.63 pg/ml, p = 0.003. Thus, it should be noted that the peripheral blood plasma level of chemokines CCL17 and CCL22 may be used as additional prognostic markers in chronic sarcoidosis with varying scoring of clinical signs including with/without systemic disease manifestations

Pediatric bacteremia and CNS infections associated with <i>klebsiella pneumoniae</i>: molecular genetic characteristics and clinical features

Klebsiella pneumoniae is one of the most significant and life-threatening pathogen of nosocomial infections. This opportunistic microorganism can cause infections of the bloodstream, respiratory tract, urinary tract, skin and soft tissues, inflammation of meninges of the brain and spinal cord, leading to elevated hospital mortality. The purpose of our study was a retrospective analysis of molecular genetic characteristics of K. pneumoniae isolated from blood and liquor samples as well as to describe clinical features in bacteremia and CNS infections. According to the results of assessed clinical data, K. pneumoniae isolates were selected from 64 children suffered from surgical pathology (congenital heart defects — 30%, abdominal pathology — 39%, severe combined trauma — 12%) and somatic diseases accompanied by antibacterial and/or glucocorticosteroid therapy — 14%. The minimum suppressive concentrations of antibiotics were determined by the broth micro-dilution method. Carbapenemases were detected by real time polymerase chain reaction. Virulence genes and capsule serotypes K1/K2 were assessed by multiplex PCR. Biofilms were grown using flat-bottomed polystyrene plates, followed by coloring, fixation, elution and data detection. The population diversity was assessed by multilocus sequence typing. Bacteremia and CNS infections associated with K. pneumoniae were fatal in 25% of cases. A substantial portion of the isolates demonstrated the phenotype of extremely drug resistance (XDR) — 43%, the phenotype of multidrug resistance (MDR) was shown in 16% of the isolates. The blaCTX-M cephalosporinase gene was found in 85% of the strains. The main determinant of resistance to carbapenems was the blaOXA-48 gene (33%); the blaNDM gene was detected in 9% of strains. The combination of blaOXA-48 and blaNDM was found in 7% of isolates. The study of biofilm production showed that moderate ability to form biofilms was shown in 61%, strong — 21%, and weak — 15% isolates. Two isolates (3%) did not form biofilms. The virulence genes entB and mrkD were detected in 100% of isolates, ybtS — in 78%. The iutA gene was found in 18% of the strains. Two isolates showed the presence of the kfu gene. Seven isolates belonged to the K2 serotype. 27 different genotypes were found in K. pneumoniae isolates examined. The most common were: ST307 — 21%, ST395 — 12%, ST48 — 7%, ST39 — 6% and ST29 — 6%. Infections of the bloodstream and central nervous system associated with K. pneumoniae have great importance in clinical practice. This microorganism is able to long persist on biotic and abiotic surfaces, has a wide natural and acquired resistance to antibiotics

DIAGNOSTIC VALUE OF SEROLOGICAL MARKERS OF RHEUMATOID ARTHRITIS

Rheumatoid arthritis (RA) is a classic autoimmune disease associated with the production of wide range of autoantibodies, and their detection has diagnostic and prognostic implication. The objective of this study was to estimate the diagnostic value of antibodies against modified citrullinated vimentin (AMCV) and nuclear antigen RA33 of the IgA rheumatoid factor (RF) versus the value of routinely used profile of autoantibodies in diagnostic work-up of RA. Material and methods. 253 patients with RA prehistory of varying duration were included into the study group. The control group was comprised of 92 patients, including patients with seronegative spondyloarthropathies and diffuse connective tissue diseases, as well as sex and age matched healthy controls. Serum levels of IgM and IgA RF, antibodies against cyclic citrullinated peptide (ACCP), ACMV, anti-keratin antibodies (AKA), antibodies against RA33 antigen (ARA33) and antinuclear factor (ANF) were measured in all patients and controls. Results and discussion. Diagnostic sensitivity of AMCV equaled 78%, ACCP — 77%, IgM RF — 71%, IgA RF — 43%, AKA — 43%, ARA33 — 31% and ANF — 31%. All anti-citrullinic antibodies (AKA, ACCP, ACMV) were significantly more commonly associated with IgM RF. Among RF and ACCP seronegative patients ACMV were found in 24% cases with 20 IU/Ml detection threshold, and in 21% — with 30 IU/Ml, allowing to increase diagnostic specificity of the test up to 91% with the increment of diagnostic threshold. Incidence of ARA33 was not significantly different among the RF and ACCP positive or negative subgroups, thus making ARA33 an independent RA marker. Specificity of this marker was 87,9%, thus making it inferior to RF and ACCP by a composite of diagnostic characteristics. Conclusions. Integrated measurement of ACMV and ARA33 is a rational approach at the second stage of serologic testing work-up in suspected cases of RA onset, when initial RF and ACCP tests were negative