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The novel coronavirus disease 2019 (COVID-19) pandemic has had a huge impact on all areas of human life. Since the risk of biological threats will persist in the future, it is very important to ensure mobilization readiness for a prompt response to the possible emergence of epidemics of infectious diseases. Therefore, from both a theoretical and practical standpoint, it is currently necessary to conduct a thorough examination of the COVID-19 epidemic. The goal of this research is to investigate the underlying processes that led to the COVID-19 pandemic in Russia and to identify ways to improve preventive measures and ensure mobilization readiness for a quick response to potential COVID-19-like pandemics. This research will analyze the daily dynamics of the number of infection cases and the number of new lethal cases of COVID-19. We analyzed the daily number of new cases of COVID-19 infection N(d), the daily number of new lethal cases L(d), their percentage ratio L(d)/N(d) 100% in Russia for 2 years of the pandemic (from the beginning of the pandemic to 23 March 2022), the rate of increase and decrease of these indicators (dN(d)/dd and dL(d)/dd), as well as their spectra created on the basis of wavelet analysis. Wavelet analysis of the deep structure of the N(d) and L(d) wavelet spectra made it possible to identify the presence of internal cycles, the study of which makes it possible to predict the presence of days with the maximum number of infections and new deaths in a pandemic similar to COVID-19 and outline ways and methods for improving preventive measures and measures to ensure mobilization readiness for a rapid response to the potential emergence of pandemics similar to COVID-19.

The authors analyzed data of governmental statistics on mortality in Russian Federation over 1970-2008, including age-related mortality coefficients for men and women and mortality causes structure. Comparative analysis covered the parameters matched by sex, age groups and the dynamics over the studied period. Findings are that social and economic crisis in 1990s in Russia had the most negative influence on able-bodied and early retired age groups - that was demonstrated by drastic increase of

Annexins belong to a family of Ca2+- and phospholipid-binding proteins that can mediate the aggregation of granules and vesicles in the presence of Ca2+. We have studied the effects of different divalent metal ions on annexin-mediated aggregation of liposomes using annexins isolated from rabbit liver and large unilamellar vesicles prepared from soybean asolectin II-S. In the course of these studies, we have found that annexin-mediated aggregation of liposomes can be driven by various earth and transition metal ions other than Ca2+. The ability of metal ions to induce annexin-mediated aggregation decreases in the order: Cd2+ > Ba2+, Sr2+ > Ca2+ >> Mn2+ > Ni2+ >> Co2+. Annexin-mediated aggregation of vesicles is more selective to metal ions than the binding of annexins to membranes. We speculate that not every type of divalent metal ion can induce conformational change sufficient to promote the interaction of annexins either with two opposing membranes or with opposing protein molecules. Relative concentration ratios of metal ions in the intimate environment may be crucial for the functioning of annexins within specialized tissues and after treatment with toxic metal ions.

After isolation of rabbit skeletal muscle membranes in the presence of Ba2+ or Ca2+, significant portions of annexin V and VI tightly bind to membranes and become inaccessible for chelating agents. Tightly bound annexin VI is virtually completely solubilized only after treatment with a buffer supplemented both with EGTA and detergent. The portion of tightly bound annexin V cannot be removed even by extraction with buffer containing both EGTA and detergent. In some cases, tightly bound annexin V or VI is detected even in the control (not treated with cations) membranes, thus indicating the possible formation of tight annexin--membrane complexes in situ. The addition of exogenous cations seems to promote only the accumulation of tightly bound annexins within the cell. After temperature-induced phase separation, annexin V and VI bound to the membranes isolated in the presence of Ba2+ or Ca2+ remains mainly in the aqueous phase, similarly to annexins isolated from the control membranes. Neither annexin partitions into the detergent-enriched phase. This indicates the absence of hydrophobicity change in comparison with the standard EGTA-soluble annexins.

Rabbit antibodies generated against annexins of human origin recognize a variety of rabbit own annexins. The antibodies under study can be divided into two groups. The first group comprises antibodies against human annexins I and IV-VI which are sufficiently specific and show only slight cross-reactivities with other proteins, whereas the second group includes antibodies against human annexins I and III which react with many different annexins and in this relation resemble consensus peptide antibodies. Antibodies of either kind can be used for identifying rabbit own annexins. This eliminates the necessity to use other laboratory animals for immunization.

Apolipoprotein B (apoB) and 40 different protein standards were submitted to sodium dodecyl sulfate-polyacrylamide gel electrophoresis under various conditions. The system selected is capable of fractionating well the apoB and its high-molecular-weight species formed after treatment of serum lipoproteins by malonic dialdehyde. The basis for good resolution of protein bands is the use of complex gels combining in one block the areas with constant (T = 3 and 10%) or continuously changing (gradient gel with T = 3-6%) concentrations of acrylamide. The procedure allows one to create the optimal conditions for simultaneous separation of both high- and low-molecular-weight polypeptides. The method was used to determine the relative molecular mass (Mr) of apoB. When apoB was isolated in the presence of proteolytic inhibitors, its Mr was found to be equal to 540,000 +/- 9500 or 500,000 +/- 5700, depending on the linear regression equation applied. The results are in good accordance with values calculated from the amino acid sequence of mature apoB.

By using extraction in the presence of Ca2+ and Triton X-100 and then in the presence of EGTA without detergent, a set of Ca2+-dependent phospholipid binding proteins has been identified in the membranes of transverse tubules (T-tubules) and sarcoplasmic reticulum (SR), isolated from rabbit skeletal muscles. Longitudinal SR, junctional SR and T-tubule membranes yielded about 9, 14 and 3.3 micrograms of EGTA-soluble proteins per 1 mg of membrane protein, respectively. In the presence of 1 mM CaCl2, 68 and 33 kDa proteins of T-tubules and junctional SR as well as 30 kDa protein of T-tubules were shown to bind to liposomes made of 1:1 w/w mixtures of (i) phosphatidylcholine and (ii) phosphatidylserine, phosphatidic acid, or phosphatidyl ethanolamine. In the presence of EGTA, the above-mentioned proteins were mostly found in the supernatants. Binding of the proteins with liposomes consisting of pure phosphatidylcholine was negligible.

Apolipoprotein B (apoB) of human plasma low-density lipoprotein has been solubilized with sodium cholate added in an amount highly above its critical micellar concentration. During isolation by gel exclusion chromatography on Sepharose CL-4B, the apoB forms mixed micelles of protein and detergent that are free of endogenous lipids. The circular dichroic spectra of the sodium cholate-solubilized apoB indicate significant heterogeneity within the fractions obtained by gel chromatography. The peak position fraction of apoB taken from the column was used for reassociation with dipalmitoyl phosphatidylcholine (DPPC). A soluble apoB-DPPC complex has been prepared by incubation of apoB-sodium cholate and DPPC-sodium cholate solutions at 42 degrees C, followed with detergent removal by extensive dialysis in the presence of a XAD-2 ion-exchange resin. Data from negative-stain electron microscopy suggests the incorporation of solubilized apoB into single-bilayer phospholipid vesicles. Upon reassociation with phospholipid, a shift (to shorter wavelengths) occurs in the intrinsic fluorescence of the apoB, thus indicating a transfer of tryptophan residues to a more hydrophobic environment. Sodium dodecylsulfate-polyacrylamide electrophoresis gives a single band (apparent Mr 370,000) for apoB after solubilization, purification and interaction with the phospholipid.

To determine the conditions under which the Ca-ATPase from rabbit skeletal sarcoplasmic reticulum can be restored to full activity, a systematic study of reactivation of lipid-depleted enzyme by various non-ionic detergents and surfactants has been carried out. All the non-ionic detergents used were able to reactivate the enzyme. The reactivation potencies of the detergents are closely related to a relative size of their polar head group and hydrophobic hydrocarbon chains. The so-called HLB (hydrophyle/lipophyle balance) numbers were used to estimate the relative hydrophobicities of the detergents studied. A striking correlation between the reactivation potency and the HLB number of any detergent was observed; the inverse correlation coefficient for small samples if equal to -0.95 +/- 0.09. The proper orientation of the ATPase protein in two different phases (lipophyle and hydrophyle) seems to be restored during reactivation. In many cases the protein-bound detergent simulates the lipid environment in the membrane sufficiently well to support the continued activity of the Ca-ATPase.

Apolipoprotein B (apoB) and 40 different protein standards have been studied at electrophoresis under various conditions of separation. The system was selected that is capable of fractionating well the apoB and its high-molecular weight species formed after the treatment of serum lipoproteins with malondialdehyde. The separation of proteins is based on the usage of complex gels combining in one unit the regions with constant (T = 3 and 10%) or continuously changing (gradient gel with T = 3-6%) concentration of acrylamide. The technique allows to create the optimum conditions for simultaneous separation of both high and low-molecular weight polypeptides. The method was applied to determine the relative molecular mass (Mr) of apoB. When apoB was isolated in strictly controlled environment its Mr has been found to be about 500-540 kilodaltons. The result is in a good accordance with the data on the amino acid sequence of mature apoB.