Cationic copolymers based on 2-(N,
-dimethylamino)ethyl methacrylate and polyethylene glycol monomethyl ether (pDMAEMA-co-PEO) with different molecular weights have been synthesized. Their ...physicochemical properties were studied by NMR spectroscopy, sedimentation, and potentiometric titration. According to the data of potentiometric titration for the synthesized pegylated cationic copolymers, the apparent dissociation constants were determined in the pH range from 4.5 to 8.5. The physicochemical properties of interpolyelectrolyte complexes of these polycations with circular DNA (IPEC DNA) were also studied by dynamic light scattering, electrophoretic mobility, and TEM methods. It has been established that the diameter and electrokinetic potential (ζ-potential) of interpolyelectrolyte complexes can be varied over a wide range (from 200 nm to 1.5 μm and from -25 mV to +30 mV) by changing the ratio of oppositely charged ionizable groups in pegylated cationic copolymers and DNA, as well as by regulating medium pH. The resistance of the IPEC DNA/polycation complex to the action of nucleases was studied by electrophoresis in agarose gel; the cytotoxic effect of the polymers in vitro, and the efficiency of penetration (transfection) of IPEC DNA with PDMAEMA-co-PEO-polycations into eukaryotic cells of a cell line derived from human embryonic kidneys HEK 293 in vitro.
Synthesis of polystyrene-block-polybutadiene (PS-b-PB) and polystyrene-block-polyisobutylene (PS-b-PIB) micelles filled with MoS x nanoparticles was carried out in a one-pot procedure in heptane ...using complexation with Mo(CO)6 followed by interaction with H2S. The structure and composition of Mo carbonyl complexes and MoS x -containing micelles were studied using FTIR, static light scattering, turbidimetry, and transmission electron microscopy. By varying the reaction atmosphere (argon or CO) during interaction with Mo(CO)6, the location of MoS x species obtained after sulfiding was tailored. Carrying out complexation with PS-b-PB in CO, which is also a reaction product, prevents complexation in the PS micelle core, thus providing location of Mo species only in the PB corona. Antifrictional tests show that this location leads to better tribological performance: lower friction coefficient or higher critical load (at which the friction coefficient is measured). When MoS x species are located in the PS core (complexation with Mo(CO)6 was carried out in argon atmosphere), low density of the micelles in the case of PS-b-PIB block copolymer with a short PS block provides much better antifrictional performance than those with the dense PS-b-PB micelles.
Integrin alpha9 (ITGA9) is one of the less studied integrin subunits that facilitates accelerated cell migration and regulates diverse biological functions such as angiogenesis, lymphangiogenesis, ...cancer cell proliferation and migration. In this work, integrin alpha9 expression and its epigenetic regulation in normal human breast tissue, primary breast tumors and breast cancer cell line MCF7 were studied. It was shown that integrin alpha9 is expressed in normal human breast tissue. In breast cancer, ITGA9 expression was downregulated or lost in 44% of tumors while another 45% of tumors showed normal or increased ITGA9 expression level (possible aberrations in the ITGA9 mRNA structure were supposed in 11% of tumors). Methylation of ITGA9 CpG-island located in the first intron of the gene was shown in 90% of the breast tumors with the decreased ITGA9 expression while no methylation at 5'-untranslated region of ITGA9 was observed. 5-aza-dC treatment restored integrin alpha9 expression in ITGA9-negative MCF7 breast carcinoma cells, Trichostatin A treatment did not influenced it but a combined treatment of the cells with 5-aza-dC/Trichostatin A doubled the ITGA9 activation. The obtained results suggest CpG methylation as a major mechanism of integrin alpha9 inactivation in breast cancer with a possible involvement of other yet unidentified molecular pathways.
WHO has declared the outbreak of monkeypox as a public health emergency of international concern. In less than three months, monkeypox was detected in more than 30 000 people and spread to more than ...80 countries around the world. It is believed that the immunity formed to smallpox vaccine can protect from monkeypox infection with high efficiency. The widespread use of Vaccinia virus has not been carried out since the 1980s, which raises the question of the level of residual immunity among the population and the identification of groups requiring priority vaccination. We conducted a cross-sectional serological study of remaining immunity among Moscow residents. To do this, a collection of blood serum samples of age group over 30 years old was formed, an
ELISA test system was developed, and a virus neutralization protocol was set up. Serum samples were examined for the presence of IgG antibodies against Vaccinia virus (
=2908), as well as for the ability to neutralize plaque formation with a Vaccinia virus MNIIVP-10 strain (
=299). The results indicate the presence of neutralizing antibody titer of 1/20 or more in 33.3 to 53.2% of people older than 45 years. Among people 30-45 years old who probably have not been vaccinated, the proportion with virus neutralizing antibodies ranged from 3.2 to 6.7%. Despite the higher level of antibodies in age group older than 66 years, the proportion of positive samples in this group was slightly lower than in people aged 46-65 years. The results indicate the priority of vaccination in groups younger than 45, and possibly older than 66 years to ensure the protection of the population in case of spread of monkeypox among Moscow residents. The herd immunity level needed to stop the circulation of the virus should be at least 50.25 - 65.28%.
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