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The well-known effect of the local interaction between graphene and photoresist (LIGF) during the creation of biosensors is shown to lead to non-uniform distribution of compressive stresses, which deteriorates the adsorption properties of graphene, parameter reproducibility, and detecting ability of influenza B and SARS-Cov-2 biosensors. It is also shown that controlling the occurrence of LIGF areas on a graphene surface by atomic force microscopy or introducing a protective layer between graphene and photoresist can minimize the non-persistent effect of LIGF. The results of influenza B and SARS-CoV-2 imaging on the graphene surface in biosensor chips in a scanning electron microscope are presented. [ABSTRACT FROM AUTHOR]

A technology for creating a Russian-made instrument platform for clinical laboratory diagnosis using biochips is described. The device is a fluorescence analyzer for recording images of fluorescent biochips at excitation wave-lengths of 520 and 633 nm and determination of the fluorescence intensities in the resulting images. [ABSTRACT FROM AUTHOR]

Seasonal and highly infectious strains of the influenza A and influenza B viruses cause millions of cases of severe complications in elderly people, children, and patients with immune diseases each year. Immunoglobulin A (IgA), which is an active component of humoral immunity, can prevent the spread of the virus in the upper respiratory tract. The preparation and study of the properties of recombinant virus-specific IgA could be an important approach to finding new means of preventing and treating influenza. Based on CHO DG44 cells, we developed stable monoclonal cell lines that produce monomeric and dimeric antibodies FI6-IgA1 and FI6-IgA2m1 to hemagglutinin (HA) of the influenza A virus. When studying the productivity, growth, and stability of the obtained clones, we found that the dimeric form of antibodies of IgA1 isotype is superior to other forms. The dimeric form of IgA antibodies plays a key role in mucosal immunity. Recognizing the prospects of using dimeric IgA as prophylactic and therapeutic mucosal drugs for viral infections, we studied their virus-neutralizing and antiviral activities on MDCK cell culture and compared them with the antibodies of the IgG1 isotype. This study presents the data on antiviral and virus-neutralizing activities of the FI6-IgA1 dimers to seasonal and highly infectious strains of influenza A virus. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the genetic determinants of Influenza A virus resistance factors to Adamantanes and neuraminidase inhibitors using biological microarrays. The study explores the culturing viruses and studying its influences on various drugs on replication and activity of its protein and its molecular genetic methods which aimed at identifying the drug-resistance-associated mutations. The study conclude the used of biochip technology in detecting infectious agents.

Copper deficiency in adult rats was induced by addition of silver chloride to the feed. The concentrations of silver, copper, iron, and zinc and relative activity of genes for copper transporting proteins and copper enzymes were measured in the cortex, cerebellum, hippocampus, amygdala, pituitary gland, and hypothalamus. Silver was accumulated only in the hypothalamic—pituitary system. These changes were accompanied by a decrease in the concentration of copper and increase in the contents of iron and zinc. Activity of genes for copper transport enzymes (high-affinity copper transporter; and two copper transport ATPases, ATP7A and ATP7B) and copper enzymes that were formed in the intracellular secretory pathway did not decrease in the brain of rats with copper deficiency. Relative activity of genes for intracellular copper enzymes (Cu2+/Zn2+ superoxide dismutase and subunit IV of cytochrome c oxidase), concentration of immunoreactive polypeptides of superoxide dismutase, and enzymatic activity of superoxide dismutase remained unchanged under these conditions. [ABSTRACT FROM AUTHOR]

The article reports on the results of a study of the effect of silver ions on copper metabolism and expression of genes encoding copper transport proteins in rat liver. A description of the experimental set-up and measurement methods is presented. The study concluded that the copper transporters promote successful uptake of silver ions, isoelectronic to copper ions by hepatocytes.

A study was made of the expression of the ceruloplasmin (Cp) gene, whose product, blue multicopper ferroxidase, acts as a neuron survival factor. Computer analysis predicted an alternative promoter in the 3′-terminal region of intron 2 of the rat Cp gene and showed that transcription from this promoter potentially yields an mRNA coding for a 109-kDa polypeptide. The alternative Cp form starts with a region of 25 amino acid residues encoded by a part of intron 2. From Gly113, its sequence is identical to that of the major Cp form. The in silico data were confirmed experimentally by RT-PCR. The predicted mRNA was found predominantly in the liver and brain of adult rats. Direct sequencing of the PCR product demonstrated the complete identity of the predicted and real mRNA sequences. It was shown in vitro that a Cp-like protein of about 110 kDa is synthesized in the cytosol and accumulates in the absence of mitochondria. The protein was transferred into isolated mitochondria in a reconstructed system. Transport was energy-dependent, was associated with no change in Cp polypeptide length, and required cytosolic factors. Mitochondrial import of the Cp form was probably determined by an internal mitochondrial localization signal, KVVYREFTDSTFRE, corresponding to region 756–769 of mature Cp. The possible role of Cp in mitochondrial iron metabolism is discussed. [ABSTRACT FROM AUTHOR]

Immunoblotting has been used to detect ceruloplasmin (Cp) polypeptides in rat mitochondria isolated from the brain, liver, testes, and mammary glands. It has been found that Cp is contained in the matrix and inner membranes of mitochondria, and that its molecular weight corresponds to the nonglycosylated form of the protein. Computer analysis has not identified sequences encoding the signal peptide for mitochondria protein import (SPMPI) in the chromosomal Cp gene of rats. However, the analysis of Cp-encoding sequences from databases has shown the presence of SPMPI nucleotide sequences in the human processed Cp pseudogene. A 984-nt region of the Cp pseudogene is translated in the only reading frame to yield a polypeptide consisting of 328 amino acid residues (aa) that contains a 66-aa SPMPI at its N-terminus. The predicted protein (without SPMPI) is 92% identical to the corresponding Cp fragment and contains 20 amino acid substitutions, including eight significant substitutions. The His-X-His motif characteristic of copper-containing ferroxidases is in the middle of the molecule. The substitution of proline by histidine at position 923 of Cp results in a potential copper-binding site. The transcription product of the Cp pseudogene has been found in cultured HepG2 and HuTu 80 human cells with the use of RT-PCR. A 30-kDa polypeptide interacting with antibodies to human Cp has been found in the mitochondria of HuTu 80 cells. The possible biological role of mitochondrial Cp is discussed. [ABSTRACT FROM AUTHOR]

Presents a study which examined the expression of ceruloplasmin (Cp) pseudogene in cultured human cells. Purpose and function of Cp in the body; Information on the process of transporting iron in cell compartments; Analysis of Cp-like protein in mammalian mitochondria.

Adhesion of protein materials with fluorescent stains to the film of GaGeS composition fabricated by the pulsed laser deposition was investigated. Resistance of the protein markers deposited onto the film to a washing in buffer isotonic solution was established. The obtained results provide the possibility to use these films for the development of protein biochips. [ABSTRACT FROM AUTHOR]

The article discusses a study that identifies proteins in complex samples by using magnetic particles conjugated to antibodies. It shows that the surface topography data do not provide any information on the presence or absence of the structures of the target protein because they were covered with excess immunoglobins unbound to the metal nanoparticles. It highlights an increase in the local concentration of magnetic nanoparticles bound to the fibrils through the immobilized antibodies.

A correction is presented to the article "In vitro Antiviral Activity of Recombinant Antibodies of IgG and IgA Isotypes to Hemagglutinin of the Influenza A Virus" which was published in previous issue of the periodical.

Due to the photoresistive properties of films in the As-S system, a two-dimensional array has been formed on a glass substrate using islands of this film. The adhesion of protein materials with fluorescent dyes to the structure obtained was studied. Selective adhesion of protein molecules to islands of a chalcogenide film has been found. The protein markers adsorbed on the film are resistant to prolonged washing in a buffer isotonic solution and water. The results obtained indicate prospects in the study of these films as a material for substrates of protein biochips. [ABSTRACT FROM AUTHOR]