Search

Myocilin is a protein with a molecular weight near 50 kDa. It is expressed in almost all organs and tissues.1 We showed that the peptide DQL ETQ TRE LET AYS NLL RD corresponding to N-terminal Leucine zipper motif (LZM) of the protein is able to form amyloid-like fibrils. The possible role of this motif in myocilin aggregation is discussed.

In the surveillance of the incidence of rubella in the northwestern region of Russia, an analysis was conducted of swabs from the noses and pharynxes of 37 patients with rubella treated in Solovev District Military Clinical Hospital No. 442. To isolate the virus, the RK-13 cell line was used, in total 22 strains were allocated. The strains of the Rubella virus isolated in St. Petersburg during the 2007 outbreak belong to the 1E genotype. In the culture of RK-13 cells, changes of cellular morphogenesis and the formation of replicative complexes, as well as the shells of virions of rubella viruses, were detected.

Therapy with anaferon (pediatric formulation) during the acute period of calicivirus infection shortened the duration of the main symptoms of the disease and period of virus release. Changes in the immunological status included increased production of IgA and IgM and activation of IFN-alpha synthesis.

The relationship between the structural and photosensitizing properties of solid-phase particles of fullerene C60 in aqueous suspensions is studied using the methods of absorption spectroscopy, electron spin resonance spectroscopy (ESR), X-ray diffraction, and spectrophotometry of solutions of singlet oxygen chemical traps—histidine in combination with p-nitrosodimethylaniline. Two new variants are proposed for obtaining aqueous suspensions of particles of solid-phase fullerene whose structures are disordered and whose degrees of amorphization are 67 and 40%, respectively. It is shown that an increase in the disorder of the structure of particles in suspensions and a decrease in their average size facilitate an increase in the formation efficiency of singlet oxygen by solid-phase fullerene presumably due to an in increase in the concentration of surface localized excitons.

The conditions of self-propagating high-temperature synthesis in a powdered sodium carbonate-magnesium mixture optimum for the preparation of the largest amount of carbon nanotubes (CNTs) were studied. The yield of nanotubes and nanofibers was weakly sensitive to the selection of the amount of a catalyst. The yield of nanotubes ceased to increase noticeably at a relative catalyst content higher than 10 wt %. For the first time, the self-propagating high-temperature reaction was performed with an iron-nickel catalyst in a limestone-magnesium mixture, that is, with the cheapest powdered reagent containing carbon. The reaction produced a small number of CNTs and nanofibers; cubic crystals, predominantly of MgO, were also observed.

The purpose of the study was to investigate the influence of cationic polymer structure on the formation of DNA-polycation complexes and their transfection activity. Primary, tertiary, and quaternary polyamines with molecular masses ranging from 8000 to 200,000 were investigated. DNA-cationic polymer interaction was characterized by low gradient viscometry, dynamic light scattering, circular dichroism, UV spectrometry, flow birefringence, DNA electrophoresis, and electron microscopy. Transfection activity of the complexes was evaluated by the expression of reporter gene (beta-galactosidase) and using synthetic FITC-labelled oligonucleotides. Complex formation was found to be dependent on the structure and molecular weight of the polymer and the ionic strength of the solution. Secondary DNA structure in complexes was not disrupted, and DNA was protected from protonation. Cell lines of different origin were used for testing of transfection activity of the complexes. The sensitivity of the cells to transfection was established to be highly dependent on the cell line. DNA-polycation complexes are non-toxic according to MTT. Polyallylamine, and polydimethylaminoethylmethacrylate were found to be the most promising polycations for gene delivery. Transfection efficacy of their complexes with DNA to T-98G cells reaches up to 90-100%. It was found that optimal molecular mass of polydimethylaminoethylmethacrylate is in the range of 8000-50,000 Da.

A mechanism of formation of fulleroid nanoparticles in shungites, adequate to the principal structural features of these particles (a cavity filled with nothing but water traces, the absence of the catalyst nanoclusters, and some other) was suggested.

Diagnostic properties of new monoclonal antibodies (MAbs) to hexon adenovirus antigen (AB) monoclonal ELISA kit for early diagnosis of adenoviral infection were tested. Developed ELISA kit and FITC-conjugate of new monocional antibodies for immunofluorescent analysis were used for detection of different types of adenoviruses in clinical materials. The availability of their use in clinical and epidemiological practice was validated.

Aqueous fullerene preparations, namely complex of C60 with polyvinylpyrrolidone (C60/PVP) and molecular‐colloidal water solutions of C60 (FWS) exhibit virocidal activity due to different mechanisms: C60/PVP complexes act mainly on the lipid component of virus membranes, while the mechanism of virocidal action of FWS is mainly connected with the ability of fullerene to generate singlet oxygen under irradiation. In the first case, fullerene acts mainly as a membranotropic agent, whereas in the second case it acts mainly as a photosensitizer.

The carbon material MNS, produced from shungite-III by successive alkaline and acid treatment, was studied. Cavitational treatment of an aqueous dispersion of the MNS material in the field of a standing acoustic wave converts a part of the substance into a material with a developed surface and a sorption capacity for hydrogen of up to 1.5%.

Polypeptide chain fragments of recombinant transthyretin (TTR) with leucine-55 substituted by proline (L55P), which are involved in abnormal fibrillogenesis of this protein, were studied. No fibrils were produced in purified preparations of TTR(L55P) under the optimum conditions for fibrillogenesis but in absence of protease inhibitors. The ability of TTR for fibrillogenesis was lost because of a limited proteolysis resulting in detachment of the TTR polypeptide chain C-terminal fragment of approximately 18 amino acid residues in length. This proteolysis seemed to occur with involvement of a bacterial serine endopeptidase sohB (EC 3.4.21), which was identified in TTR preparations by the MALDI-TOF method. The presence of the C-terminal fragment of the TTR polypeptide chain seems to be crucial for production of abnormal fibrils.

Conditions for preparing stable aqueous micellar solution of nonmodified fullerene C60 were optimized. The size distribution of the micellar particles was determined by transmission electron microscopy, and the negative charge of the micelles was proved. The mean particle diameter appeared to be ∼2.5 times smaller than that determined by dynamic light scattering. The possibility of generation of singlet oxygen in the modified system C60/H2O was demonstrated. The 1O2 luminescence signal at λ = 1268 nm lasts for ∼3 μs.

Emulsion polymerization of styrene in the presence of an anionic surfactant, sodium dodecyl sulfate, in a concentration close to the critical micellization concentration, was studied, as influenced by the pH of the initial reaction mixture and the content of the carboxyl-containing azoinitiator.

The fibrillogenesis of a peptide corresponding to residues 35-51 of human α-lactalbumin (¹GYDTQAIVENNESTEYG¹⁷) can be dramatically enhanced by the addition of a tetrapeptide TDYG homologous to its C-terminus (TEYG). Generation of spontaneous hydrolytic products similar to this peptide was demonstrated by mass-spectrometry analysis of GYDTQAIVENNESTEYG peptide solution components during fibrillogenesis. Possible mechanisms and roles of short peptides in protein metabolism are discussed.

A mirror-symmetry motif was discovered in the N-terminus of the influenza virus PB1 protein. Structure of peptide comprised of the corresponding part of PB1 (amino acid residues 6-25) was investigated by circular dichroism and in silico modeling. We found that peptide PB1 (6-25) in solution assumes beta-hairpin conformation. A truncated peptide PB1 (6-13), containing only half of the mirror-symmetry motif, appeared to stabilize the beta-structure of the original peptide and, at high concentrations, was capable of reacting with peptide to form insoluble aggregates in vitro. Ability of PB1 (6-13) peptide to interact with the N-terminal domain of PB1 protein makes it a potential antiviral agent that inhibits PA-PB1 complex formation by affecting PB1 N-terminus structure.

In the surveillance of rubella in the northwest region of Russia samples of nasopharyngeal swabs from 37 patients with rubella, which were treated in the 442nd district military hospital named after Z.P. Solovyov in autumn 2007 were screened for the rubella virus using RK-13 cell line, 22 strains of rubella virus were isolated. Gene sequencing of E1 region of rubella virus isolates was carried out. Rubella virus strains isolated in St. Petersburg during the 2007 outbreak belonged to rubella virus genotype 1E. The morphogenesis of RK-13 cells with formation of replication complexes and enveloped virions of rubella virus was shown.

The goal of this study was to evaluate the effect of Ingavirin on the morphological features of the foci of adenovirus hepatitis in Syrian hamsters by electron microscopy. The use of the drug was shown to cause a substantial reduction in the rate of destructive processes and inflammatory reactions in the liver, by normalizing its structure at the levels of both tissue and individual hepatocytes. After administration of Ingavirin, the morphogenesis of adenovirus infection in the infected hepatocytes did not differ from that in the controls; however, the infected cells were fewer. The proportion of morphologically inadequate virions in the presence of Ingavirin increased from 35 to 46%. The findings suggest that Ingavirin is an effective drug that has antiviral, anti-inflammatory, and cytoprotective activities in the focus of adenovirus tissue involvement.

In addition to maintaining the GenBank® nucleic acid sequence database, the National Center for Biotechnology Information (NCBI) provides analysis and retrieval resources for the data in GenBank and other biological data made available through the NCBI Website. NCBI resources include Entrez, the Entrez Programming Utilities, MyNCBI, PubMed, PubMed Central (PMC), Gene, the NCBI Taxonomy Browser, BLAST, BLAST Link (BLink), Primer-BLAST, COBALT, Splign, RefSeq, UniGene, HomoloGene, ProtEST, dbMHC, dbSNP, dbVar, Epigenomics, Genome and related tools, the Map Viewer, Model Maker, Evidence Viewer, Trace Archive, Sequence Read Archive, BioProject, BioSample, Retroviral Genotyping Tools, HIV-1/Human Protein Interaction Database, Gene Expression Omnibus (GEO), Probe, Online Mendelian Inheritance in Animals (OMIA), the Molecular Modeling Database (MMDB), the Conserved Domain Database (CDD), the Conserved Domain Architecture Retrieval Tool (CDART), Biosystems, Protein Clusters and the PubChem suite of small molecule databases. Augmenting many of the Web applications are custom implementations of the BLAST program optimized to search specialized data sets. All of these resources can be accessed through the NCBI home page at www.ncbi.nlm.nih.gov.

The effect of meglumine salt of acridonoacetic acid (cycloferon) on the in vivo morphogenesis of influenza infection caused by viruses of different origin (avian, swine and human) and variable susceptibility to antivirals (rimantadine and oseltamivir) has been studied. The administration of cycloferon results in stimulation of the immune response, restriction of the foci of post-influenza pneumonia, and normalization of the structure of respiratory zones independently of the susceptibility or resistance of infectious virus to the drugs. Among virions formed in the lungs of cycloferon-treated mice, prevalence of irregular-shaped virions with defects of surface glycoproteins was observed. The data obtained suggest that cycloferon is a drug with the complex mechanism of activity.

Equations which describe the evolution of the bubble spectrum in the process of cavitational fragmentation by a shock wave reflected from a free liquid surface are formulated. As an example, the effect of artificial saturation of the initial fluid with large bubbles on the dispersity of a liquid-drop gas suspension focused by dispersion is investigated.

The problem of cavitation in the tension wave associated with the reflection of a shock wave from a free fluid surface is considered. A method of calculating the cavitation zone dynamics which makes it possible to determine the structure of the cavitation front, including for large space scales, is developed. A procedure for determining the dispersity of the fragment-drops of dispersed fluid, which takes into account the initial size distribution of the cavitation nuclei and the parameters of the incident shock wave, is proposed.

In addition to maintaining the GenBank® nucleic acid sequence database, the National Center for Biotechnology Information (NCBI) provides analysis and retrieval resources for the data in GenBank and other biological data made available through the NCBI Web site. NCBI resources include Entrez, the Entrez Programming Utilities, MyNCBI, PubMed, PubMed Central (PMC), Entrez Gene, the NCBI Taxonomy Browser, BLAST, BLAST Link (BLink), Primer-BLAST, COBALT, Electronic PCR, OrfFinder, Splign, ProSplign, RefSeq, UniGene, HomoloGene, ProtEST, dbMHC, dbSNP, dbVar, Epigenomics, Cancer Chromosomes, Entrez Genomes and related tools, the Map Viewer, Model Maker, Evidence Viewer, Trace Archive, Sequence Read Archive, Retroviral Genotyping Tools, HIV-1/Human Protein Interaction Database, Gene Expression Omnibus (GEO), Entrez Probe, GENSAT, Online Mendelian Inheritance in Man (OMIM), Online Mendelian Inheritance in Animals (OMIA), the Molecular Modeling Database (MMDB), the Conserved Domain Database (CDD), the Conserved Domain Architecture Retrieval Tool (CDART), IBIS, Biosystems, Peptidome, OMSSA, Protein Clusters and the PubChem suite of small molecule databases. Augmenting many of the Web applications are custom implementations of the BLAST program optimized to search specialized data sets. All of these resources can be accessed through the NCBI home page at www.ncbi.nlm.nih.gov.

Viruses are the most dangerous contaminants of human blood and blood products. The purpose of this study was to investigate the light-mediated virus-inactivating properties of fullerene and its effect on the intactness of biological fluids. Influenza virus was propagated in chicken embryos, and a water suspension of C60 fullerene was added to the allantoic fluid. The fluid was light-irradiated with a constant flow of oxygen through the specimen, and the dynamics of the virus titer were studied in Madin-Darby canine kidney (MDCK) cells. The morphology of the virions was studied by electron microscopy (EM). The electrophoretic pattern of the proteins in the allantoic fluid and blood plasma, as well as the growth properties of the calf serum were compared before and after 6h of irradiation. A dramatic drop of infectious titer (from 6 to 0 log10 EID50) in the virus was observed within 2h after the start of irradiation. No change in the titers was observed in control specimens without the fullerene, or light, or oxygen. EM revealed numerous defects in the morphology of the virions (destruction of the outer membrane) leading to the loss of infectious properties in the virus. Based on comparison of proteins and growth properties of the serum, no differences were revealed between intact and irradiated biological fluids. Water-insoluble fullerenes may therefore be considered an effective and safe way to inactivate enveloped viruses in biological materials including blood products.

The reproduction of the new coronavirus HCoV/SPb/01/03 in the cultured human embryo lung fibroblasts (HELFBs) was electron microscopically studied. The virus was shown to replicate in the cultured HELFBs, by using for this a cell membrane system and causing profound changes in its morphology. After 24 hours of cell infection, there were mature and defective HCoVISPb/01/03 virions were detected in the vacuoles near the peripheral cisterns of the Golgi apparatus. Some of the vacuoles contained folded membranous structures along with virions.

As the result of prolonged (17 years) observations of patients with acute respiratory infections hospitalized in basic departments of clinics of the Research Institute of Influenza, coronavirus infection was found to be the cause of respiratory diseases, on the average, in 12% of cases (in some years in 6.8% to 28.6% of cases). The analysis of extensive morbidity rates among different age groups of the population showed that children were affected by coronavirus infection 5-7 times more often than adults. Three year cycles of this infection were established. The periods of coronaviruses activation were accompanied by their detection in patient material by electron-microscopy, a sharp increase of immune response of patients as well as in the number of nosocomial infections and the proportion of the monoinfection of the coronavirus nature. Coronaviruses played the leading role among other viruses in the etiology of hospital respiratory infections. Mucosal antibodies to coronaviruses in the secretions of the nasal cavity proved to be more important than serum antibodies not only in protection from infection, but also in the pattern of clinical manifestations of the disease.

Conditions were developed for obtaining surface viral glycoprotein (GP) fraction intended for solid phase sensitization with the aim of constructing enzyme immunoassay test systems (EIATS) for detection of subtypical IgG and IgG to influenza A (H1N1) and A (H3N2) viruses. New variants of test systems were compared with the traditional methods for serological diagnosis of influenza. GP-based EIATS more often diagnosed influenza than EIATS based on purified whole-virion (WV) suspensions, hemagglutination inhibition and neutralization tests. Evaluation of conversions of subtypical IgG showed that the results coincided with the findings of neutralization and hemagglutination inhibition tests in 83-90% (EIATS-GP) and 50% (EIATS-WV). Cross-detection of antibodies to both virus subtypes in EIATS-GP and EIATS-WV was observed in 4 and 31% cases, respectively.

Respiratory syncytial virus (RSV), strain Long, was purified through 20-60% sucrose gradient. The virions from different sucrose density zones were tested by ELISA for reactivity with monoclonal antibodies (MAB) to F- (MAB 9C5) and N- (MAB 8B10) proteins of RSV. Comparative study of the same patterns of RSV by electron microscopy after negative staining showed a close relationship between the virion morphology and MAB binding in ELISA. MAB 9C5 were highly reactive with the surface domains of both mature RSV virions and "empty" virion envelopes without formed inner nucleocapsid structures. MAB 8B10 reacted well only with mature virions with completely assembled nucleocapsids. These MAB failed to reorganize the N-protein epitope of immature and destroyed virions, which indicated a conformation dependence of the 8B10 binding site. For practical purposes, MAB tests can be used to determine the RSV patterns, which can be used in ELISA for serologic diagnosis of RSV infection. Testing with these MAB demonstrate the stability of RSV to extreme exposures (lyophilization, storage, heating), which is important for creation of sensitive ELISA test systems and their standardization.

A new type of solid-phase photosensitizer has been proposed and created on the basis of aggregated fullerene C60 for the photodynamic inactivation of pathogens in biological liquids. This paper demonstrates the chief advantage of such solid-phase systems, which is that efficient inactivation of pathogens (using influenza viruses as an example) by active forms of oxygen formed when a photosensitizer is irradiated in aqueous and biological media is combined with high photostability of the fullerene coatings and the possibility of completely extracting the photosensitizer from the biological medium after photodynamic activation.