Structural Basis for Evasion of New SARS-CoV-2 Variants from the Potent Virus-Neutralizing Nanobody Targeting the S-Protein Receptor-Binding Domain.

COVID-19 has caused millions of deaths and many times more infections worldwide, emphasizing the unpreparedness of the global health system in the face of new infections and the key role for vaccines and therapeutics, including virus-neutralizing antibodies, in prevention and containment of the disease. Continuous evolution of the SARS-CoV-2 coronavirus has been causing its new variants to evade the action of the immune system, which highlighted the importance of detailed knowledge of the epitopes of already selected potent virus-neutralizing antibodies. A single-chain antibody ("nanobody") targeting the SARS-CoV-2 receptor-binding domain (RBD), clone P2C5, had exhibited robust virus-neutralizing activity against all SARS-CoV-2 variants and, being a major component of the anti-COVID-19 formulation "GamCoviMab", had successfully passed Phase I of clinical trials.

Experimental Use of Common Marmosets (Callithrix jacchus) in Preclinical Trials of Antiviral Vaccines.

Common marmoset (, CM) is a New World primate species that is of interest for preclinical trials of immunobiological products. In this study, we describe the approaches to long-term laboratory breeding and maintenance of CMs. We also establish the reference values of the main complete blood count and serum chemistry parameters evaluated during preclinical trials of immunobiological products and describe the histological characteristics of CM lymphoid organs during the development of post-vaccination immune response.

Dual-Functional Implant Based on Gellan-Xanthan Hydrogel with Diopside, BMP-2 and Lysostaphin for Bone Defect Repair and Control of Staphylococcal Infection.

A new dual-functional implant based on gellan-xanthan hydrogel with calcium-magnesium silicate ceramic diopside and recombinant lysostaphin and bone morphogenetic protein 2 (BMP-2)-ray is developed. In this composite, BMP-2 is immobilized on microparticles of diopside while lysostaphin is mixed directly into the hydrogel, providing sustained release of BMP-2 to allow gradual bone formation and rapid release of lysostaphin to eliminate infection immediately after implantation. Introduction of diopside of up to 3% (w/v) has a negligible effect on the mechanical properties of the hydrogel but provides a high sorption capacity for BMP-2.

Synthesis of Substituted 1,2,4-Triazole-3-Thione Nucleosides Using Purine Nucleoside Phosphorylase.

1,2,4-Triazole derivatives have a wide range of biological activities. The most well-known drug that contains 1,2,4-triazole as part of its structure is the nucleoside analogue ribavirin, an antiviral drug. Finding new nucleosides based on 1,2,4-triazole is a topical task.

Combined Light and Thermal Stimulation of Bone Marrow Stem Cells.

The purpose of this study is to achieve a significant increase in the proliferative activity of mesenchymal stem cells (MSCs) of the bone marrow (BM) at early passages after laser exposure to a suspension of these cells and to estimate the effect of light and heat components of laser radiation on the proliferation of BM MSCs. The studies were performed on rats BM MSCs. MSC suspension was placed into the wells and heated by using laser radiation (980 nm wavelength) or a water bath at 70 °C providing similar temperature dynamics.

Polyamine Catabolism Revisited: Acetylpolyamine Oxidase Plays a Minor Role due to Low Expression.

Biogenic polyamines are ubiquitous compounds. Dysregulation of their metabolism is associated with the development of various pathologies, including cancer, hyperproliferative diseases, and infections. The canonical pathway of polyamine catabolism includes acetylation of spermine and spermidine and subsequent acetylpolyamine oxidase (PAOX)-mediated oxidation of acetylpolyamines (back-conversion) or their direct efflux from the cell.

Modeling hepatitis A epidemiological profiles and estimating the pediatric vaccination threshold in the Russian Federation.

Background: To combat the hesitancy towards implementing a hepatitis A universal mass vaccination (UMV) strategy and to provide healthcare authorities with a comprehensive analysis of the potential outcomes and benefits of the implementation of such a vaccination program, we projected HAV seroprevalence and incidence rates in the total population of the Russian Federation and estimated the pediatric vaccination threshold required to achieve an incidence level of less than 1 case per 100,000 using a new mathematical model.

Methods: A dynamic age-structured SEIRV (susceptible-exposed-infectious-recovered-vaccinated) compartmental model was developed and calibrated using demographic, seroprevalence, vaccination, and epidemiological data from different regions of the Russian Federation. This model was used to project various epidemiological measures.

New synthesis of oligosaccharides modelling the M epitope of the O-polysaccharide.

Brucellosis is a dangerous zoonotic disease caused by bacteria of the genus . Diagnosis of brucellosis is based on the detection in animal and human sera of antibodies to the O-polysaccharide of lipopolysaccharide. The currently employed serodiagnosis of brucellosis relies on the use of the O-polysaccharide as a diagnostic antigen.

ATP and Formyl Peptides Facilitate Chemoattractant Leukotriene-B4 Synthesis and Drive Calcium Fluxes, Which May Contribute to Neutrophil Swarming at Sites of Cell Damage and Pathogens Invasion.

Here, we demonstrate that human neutrophil interaction with the bacterium fuels leukotriene B4 synthesis induced by the chemoattractant fMLP. In this work, we found that extracellular ATP (eATP), the amount of which increases sharply during tissue damage, can effectively regulate fMLP-induced leukotriene B4 synthesis. The vector of influence strongly depends on the particular stage of sequential stimulation of neutrophils by bacteria and on the stage at which fMLP purinergic signaling occurs.

A New "Non-Traditional" Antibacterial Drug Fluorothiazinone-Clinical Research in Patients with Complicated Urinary Tract Infections.

In order to combat resistance, it is necessary to develop antimicrobial agents that act differently from conventional antibiotics. Fluorothiazinone, 300 mg tablet (The Gamaleya National Research Center), is an original antibacterial drug based on a new small molecule T3SS and flagellum inhibitor. A total of 357 patients with complicated urinary tract infections (UTIs) were divided into two groups and given Fluorothiazinone 1200 mg/day or a placebo for 7 days to evaluate the efficacy and safety of the drug.

Assessment of Modulating Effect of the Experimental Drug Astrabionorm on Synthesis of Proinflammatory Cytokine IL-1β and Anti-Inflammatory Cytokine IL-10 in the Splenic Red Pulp Cells in a Mouse Model of Sepsis.

An indirect immunohistochemical method was used to study the production of proinflammatory (IL-1β) and anti-inflammatory (IL-10) cytokines in the spleen cells of mature male C57BL/6 mice with an experimental model of sepsis and during treatment with a drug based on formic acid aldehyde (Astrabionorm). Clinical isolates of two strains of Pseudomonas aeruginosa were used. In the red pulp of the spleen, interleukin-positive cells represented by mononuclear forms were identified, as well as differences in the intensity of immunohistochemical staining of these cells for the studied interleukins in the two models used.

Optimizing Antimicrobial Peptide Design: Integration of Cell-Penetrating Peptides, Amyloidogenic Fragments, and Amino Acid Residue Modifications.

The escalating threat of multidrug-resistant pathogens necessitates innovative approaches to combat infectious diseases. In this study, we examined peptides R23F*, V31K*, and R44K*, which were engineered to include an amyloidogenic fragment sourced from the S1 protein of , along with one or two cell-penetrating peptide (CPP) components. We assessed the antimicrobial efficacy of these peptides in a liquid medium against various strains of both Gram-positive bacteria, including (209P and 129B strains), MRSA (SA 180 and ATCC 43300 strains), and (strain IP 5832), and Gram-negative bacteria such as (ATCC 28753 and 2943 strains) and (MG1655 and K12 strains).

Optical detection of infectious SARS-CoV-2 virions by counting spikes.

Existing methods for the mass detection of viruses are limited to the registration of small amounts of a viral genome or specific protein markers. In spite of high sensitivity, the applied methods cannot distinguish between virulent viral particles and non-infectious viral particle debris. We report an approach to solve this long-standing challenge using the SARS-CoV-2 virus as an example.

PhyloBench: A Benchmark for Evaluating Phylogenetic Programs.

Phylogenetic inference based on protein sequence alignment is a widely used procedure. Numerous phylogenetic algorithms have been developed, most of which have many parameters and options. Choosing a program, options, and parameters can be a nontrivial task.

Avian flu: «for whom the bell tolls»?

The family consists of 9 genera, including which contains avian influenza viruses. In two subtypes H5 and H7 besides common low-virulent strains, a specific type of highly virulent avian virus have been described to cause more than 60% mortality among domestic birds. These variants of influenza virus are usually referred to as «avian influenza virus».

Protease S of entomopathogenic bacterium Photorhabdus laumondii: expression, purification and effect on greater wax moth Galleria mellonella.

Background: Protease S (PrtS) from Photorhabdus laumondii belongs to the group of protealysin-like proteases (PLPs), which are understudied factors thought to play a role in the interaction of bacteria with other organisms. Since P. laumondii is an insect pathogen and a nematode symbiont, the analysis of the biological functions of PLPs using the PrtS model provides novel data on diverse types of interactions between bacteria and hosts.

Rev Protein Diversity in HIV-1 Group M Clades.

The HIV-1 Rev protein expressed in the early stage of virus replication is involved in the nuclear export of some forms of virus RNA. Naturally occurring polymorphisms in the Rev protein could influence its activity. The association between the genetic features of different virus variants and HIV infection pathogenesis has been discussed for many years.

(Heteroarylmethyl)benzoic Acids as a New Class of Bacterial Cystathionine γ-Lyase Inhibitors: Synthesis, Biological Evaluation, and Molecular Modeling.

Antibiotic resistance is one of the most serious global health threats. Therefore, there is a need to develop antimicrobial agents with new mechanisms of action. Targeting of bacterial cystathionine γ-lyase (bCSE), an enzyme essential for bacterial survival, is a promising approach to overcome antibiotic resistance.

Airway basal cells from human-induced pluripotent stem cells: a new frontier in cystic fibrosis research.

Human-induced airway basal cells (hiBCs) derived from human-induced pluripotent stem cells (hiPSCs) offer a promising cell model for studying lung diseases, regenerative medicine, and developing new gene therapy methods. We analyzed existing differentiation protocols and proposed our own protocol for obtaining hiBCs, which involves step-by-step differentiation of hiPSCs into definitive endoderm, anterior foregut endoderm, NKX2.1+ lung progenitors, and cultivation on basal cell medium with subsequent cell sorting using the surface marker CD271 (NGFR).