INCLUSION OF SITE-SPECIFIC MUTATIONS INTO CONSERVATIVE SEG- MENTS OF PA-GENE RESULTS IN ATTENUATION OF VIRULENT INFLUENZA VIRUS STRAIN A/WSN/33.

Aim: Study the possibility of obtaining attenuated variants of influenza virus by including specially selected site-specific mutations into a conservative sequence of PA-gene (terminal segment of COOH-domain of the PA-gene) of a virulent strain.

Materials And Methods: A/ WSN/33 - a virulent strain of influenza virus was used in the study. Inclusion of site-specif- ic mutations into PA-gene of the A/WSN/33 virulent strain was carried out using a two-step mutation PCR.

Exosomal Annexin II Promotes Angiogenesis and Breast Cancer Metastasis.

Unlabelled: Tumor-derived exosomes are emerging mediators of tumorigenesis and tissue-specific metastasis. Proteomic profiling has identified Annexin II as one of the most highly expressed proteins in exosomes; however, studies focused on the biological role of exosomal Annexin II (exo-Anx II) are still lacking. In this study, mechanistic insight was sought regarding exo-Anx II and its function in angiogenesis and breast cancer metastasis.

[COLD-ADAPTED A/KRASNODAR/101/35/59 (H2N2) STRAIN--A PROMISING STRAIN-DONOR OF ATTENUATION FOR PROCURATION OF LIVE INFLUENZA VACCINES].

Aim: Study of ts, ca, att phenotype, immunogenicity and protective effectiveness of reassortants obtained by a way of recombination of a new influenza cold-adapted (ca) strain donor of attenuation A/Krasnodar/101/35/59 (H2N2) and virulent strain of influenza virus.

Materials And Methods: Viruses were used: ca strain A/Krasnodar/101/35.59 (H2N2), virulent strains: A/Kumamoto/102/02 (H3N2) and A/Bern/07/95.

Steady State and Time Resolved Fluorescence Studies of Azadioxatriangulenium (ADOTA) Fluorophore in Silica and PVA Thin Films.

A cationic azadioxatriangulenium (ADOTA) dye was entrapped in silica thin films obtained by the sol-gel process and in poly (vinyl) alcohol (PVA) thin films. Azadioxatriangulenium is a red emitting fluorophore with a long fluorescence lifetime of ~20 ns. The fluorescent properties of azadioxatriangulenium in silica thin films and PVA films were studied by means of steady-state and time resolved fluorescence techniques.

Preparation of plasmonic platforms of silver wires on gold mirrors and their application to surface enhanced fluorescence.

In this report we describe a preparation of silver wires (SWs) on gold mirrors and its application to surface enhanced fluorescence (SEF) using a new methodology. Silica protected gold mirrors were drop-coated with a solution of silver triangular nanoprisms. The triangular nanoprisms were slowly air-dried to get silver wires that self-assembled on the gold mirrors.

Pre-Clinical Evaluation of rHDL Encapsulated Retinoids for the Treatment of Neuroblastoma.

Despite major advances in pediatric cancer research, there has been only modest progress in the survival of children with high risk neuroblastoma (NB) (HRNB). The long term survival rates of HRNB in the United States are still only 30-50%. Due to resistance that often develops during therapy, development of new effective strategies is essential to improve the survival and overcome the tendency of HRNB patients to relapse subsequent to initial treatment.

Real-time imaging of exocytotic mucin release and swelling in Calu-3 cells using acridine orange.

Mucus secretion is the first-line of defence against the barrage of irritants inhaled into human lungs, but abnormally thick and viscous mucus results in many respiratory diseases. Understanding the processes underlying mucus pathology is hampered, in part, by lack of appropriate experimental tools for labeling and studying mucin granule secretion from live cells with high sensitivity and temporal resolution. In this report we present original spectroscopic properties of acridine orange (AO) which could be utilized to study granule release and mucin swelling with various advanced fluorescence imaging approaches.

[New cold-adapted donor strains for live influenza vaccine].

Cold-adapted (CA) strains A/Krasnodar/35 and B/Victoria/63 were isolated using passages of A/Krasnodar/101/59 and B/Victoria/2/87 wild type strains at low temperatures. The resulting CA strains possessed TS and CA phenotypes and had a reduced ability to reproduce in mouse lungs and nasal turbinates. They displayed a high protective efficacy in experiments on mice.

Fluorescent Polyelectrolyte Capped Silver Nanoclusters: Optimization and Spectroscopic Evaluation.

In the present work, we have synthesized water soluble Ag nanoclusters using PMAA as a template with different Ag+: COO-ratios, to optimize it for highest brightness using less UV exposure time. Fluorescence polarization was 0.30 for and was found to vary with excitation and emission wavelength with few hundred picoseconds average fluorescence lifetime.

YY1 and a unique DNA repeat element regulates the transcription of mouse CS1 (CD319, SLAMF7) gene.

CS1 (CD319, CRACC, SLAMF7, novel Ly9) activates NK cell-mediated cytotoxicity and proliferation of B lymphocytes during immune responses. The expression of CS1 is up regulated on B cells in multiple myeloma and systemic lupus erythematosus. In this study we describe the transcriptional regulation of mouse CS1 (mCS1) gene.

Sigma-1 receptor stimulation attenuates calcium influx through activated L-type Voltage Gated Calcium Channels in purified retinal ganglion cells.

Sigma-1 receptors (σ-1rs) exert neuroprotective effects on retinal ganglion cells (RGCs) both in vivo and in vitro. This receptor has unique properties through its actions on several voltage-gated and ligand-gated channels. The purpose of this study was to investigate the role that σ-1rs play in regulating cell calcium dynamics through activated L-type Voltage Gated Calcium Channels (L-type VGCCs) in purified RGCs.

[Increasing the immunogenicity of inactivated chitosan adjuvanted vaccine from A/California/7/09 (H1N1) strain and analyzing the antigenic specificity of this influenza virus strain].

Addition of chitosan as an adjuvant to subunit vaccine from the swine origin influenza virus A/California/7/09 (H1N1) increases vaccine immunogenicity by 8-16 times and significantly enhances its protective potency. Single immunization with chitosan adjuvanted vaccine induced similar antibody titers as two immunizations with unadjuvanted vaccine. Chitosan stabilized the immunogenicity of subunit vaccine when stored at 4 degrees C.

Metal-enhanced immunoassays.

The surface-confined assay format is one of the most convenient detection formats used in many immunoassays. Fluorescence emission from monolayers of dyes requires a strong excitation and good detection system. Such samples are susceptible to artifacts due to background fluorescence from substrates.

FRET enhanced fluorescent nanodiamonds.

Fluorescent nanodiamonds (FNDs) are one of the new and very promising biocompatible nanomaterials that can be used both as a fluorescence imaging agent and a highly versatile platform for controlled functionalization to target and deliver a wide spectrum of therapeutic agents. Among the remarkable fluorescence properties are excellent photostability, emission between 600-700nm, quantum yield of 1 and moderately long fluorescence lifetimes. However the low absorption cross section of fluorescent (N-V)(-) centers limits FNDs' brightness.

[Enhancing the immunogenicity of inactivated polio vaccines with chitosan used as an adjuvant].

Addition of chitosan to inactivated trivalent polio vaccine or inactivated preparations of attenuated poliomyelitis viruses (Sabin strains) significantly increases immunogenicity of these inactivated poliomyelitis virus preparations. High neutralizing antibody titers are detected after two immunizations of mice and a single immunization of rats, as well as when the antigen dose was reduced by 4 times. Addition of chitosan as an adjuvant significantly induces cellular immunity.

[Investigation of antiviral activity of adamantan boron derivaties on pandemic influenza virus models].

Comparative investigation of the virus-inhibiting activity of some boron-containing compounds showed that products BG 12 and BG 4 had the highest inhibitory effect on pandemic viruses. The minimum inhibitory concentration (MIC) of the products was 0.1 mcg/ml.

Imaging exocytosis of ATP-containing vesicles with TIRF microscopy in lung epithelial A549 cells.

Nucleotide release constitutes the first step of the purinergic signaling cascade, but its underlying mechanisms remain incompletely understood. In alveolar A549 cells much of the experimental data is consistent with Ca(2+)-regulated vesicular exocytosis, but definitive evidence for such a release mechanism is missing, and alternative pathways have been proposed. In this study, we examined ATP secretion from A549 cells by total internal reflection fluorescence microscopy to directly visualize ATP-loaded vesicles and their fusion with the plasma membrane.

Reactive oxygen species-mediated TRPC6 protein activation in vascular myocytes, a mechanism for vasoconstrictor-regulated vascular tone.

Both TRPC6 and reactive oxygen species (ROS) play an important role in regulating vascular function. However, their interplay has not been explored. The present study examined whether activation of TRPC6 in vascular smooth muscle cells (VSMCs) by ROS was a physiological mechanism for regulating vascular tone by vasoconstrictors.

Chitosan as an adjuvant for poliovaccine.

The use of inactivated poliomyelitis vaccine is very important for eradicating poliomyelitis. However, this vaccine is not available readily in underdeveloped countries due to the high cost. Adjuvants can improve the immunogenicity of a vaccine and reduce the antigen dose required for vaccination, thus lowering the cost of the vaccine.

Förster resonance energy transfer evidence for lysozyme oligomerization in lipid environment.

Intermolecular time-resolved and single-molecule Förster resonance energy transfer (FRET) have been applied to detect quantitatively the aggregation of polycationic protein lysozyme (Lz) in the presence of lipid vesicles composed of phosphatidylcholine (PC) and its mixture with 5, 10, 20, or 40 mol % of phosphatidylglycerol (PG) (PG5, PG10, PG20, or PG40, respectively). Upon binding to PC, PG5, or PG10 model membranes, Lz was found to retain its native monomeric conformation, while increasing content of anionic lipid up to 20 or 40 mol % resulted in the formation of Lz aggregates. The structural parameters of protein self-association (the degree of oligomerization, the distance between the monomers in protein assembly, and the fraction of donors present in oligomers) have been derived.

[Increase of immunogenicity of cold-adapted influenza vaccine by using adjuvant].

Aim: To assess increase of protective efficacy of live cold-adapted (ca) influenza vaccine after addition of adjuvant chitozan.

Materials And Methods: Used viruses: ca donor of attenuation A/Krasnodar/101/35/59 (H2N2) and epidemic strain A/Krasnodar/101/59 (H2N2); as an adjuvant--derivative of chitozan and microparticles of chitozan. Experiments were performed in outbred mice.

Morphological changes of supported lipid bilayers induced by lysozyme: planar domain formation vs. multilayer stacking.

Total internal reflection fluorescence microscopy (TIRFM) has been utilized to explore the effect of cationic protein lysozyme (Lz) on the morphology of solid-supported lipid bilayers (SLBs) comprised of zwitterionic lipid phosphatidylcholine (PC) and its mixture with anionic lipid cardiolipin (CL). Kinetic TIRFM imaging of different systems revealed subtle interplay between lipid lateral segregation accompanied by exchange of neutral and acidic lipids in the protein-lipid interaction zone, and the formation of lipid multilayer stacks. The switch between these states was shown to be controlled by CL content.

Nanostructured silver-based surfaces: new emergent methodologies for an easy detection of analytes.

In this work, we describe how to realize a new sensing platform for an easy and fast detection of analytes. In particular, we utilized enhanced fluorescence emission on silver island films (SIFs) coupled to the total internal reflection fluorescence mode (TIRF) to develop a new assay format for the detection of target analytes. Here, as an example, we report on the detection of the toxic peptides present in gliadin (Gli).

Enhanced Fluorescence Emission of Me-ADOTA by Self-Assembled Silver Nanoparticles on a Gold Film.

We report a multi-fold enhancement of the fluorescence of methyl-azadioxatriangulenium chloride (Me-ADOTA*Cl) in PVA deposited on a 50 nm thick gold mirror carrying an evaporation induced self-assembly of colloidal silver nanoparticles (Ag-SACs). The average measured increase in fluorescence emission of about 50-fold is accompanied by hot spots with a local enhancement in brigthness close to 200. The long lifetime of the dye allows for the first direct determination of the correlation between the enhancement of emission intensity and the decrease in fluorescence lifetime.

Single molecule immunoassay on plasmonic platforms.

We examined the photophysical properties of the new near infrared (NIR) fluorescent label SeTau-665 on a plasmonic platform of self- assembled colloidal structures (SACS) of silver prepared on a semitransparent silver film. A SeTau-665 immunoassay was performed on this platform and a control glass slide. The fluorescence properties of this label substantially change due to plasmonic interactions.