Hydrophobic composition based on mixed-molecular weight polyethylene

The paper presents investigations of compositions based on low and high molecular weight polyethylene so as to synthesize a hydrophobic composition for moisture protection of timber. X-ray phase analysis and measurements of the tear-off force of hydrophobic coating needed to apply to the timber surface and the limiting wetting angle are carried out to detect the hydrophobic, adhesive, electrophysical, and physicochemical properties of compositions. Kinetic dependencies are given for moisture absorption of timber specimens. It is shown that the preliminary formation of the texture by the surface patterning or its treatment with low-temperature plasma with the following protective coating results in the improvement of hydrophobic properties of the suggested compositions. These compositions can be used in the capacity of water repellents to protect building materials from moisture including restoration works

Water-repellent coatings for surface and 3D wood processing

The paper presents the results of research in organic chemical compositions for hydrophobic protection of wood with the use of surface and three-dimensional coating techniques of impregnation and chemical compositions. Water absorption indicators, angles of contact on the surface of treated samples are detected herein. Kinetic equation of the moisture diffusion transition in capillary-porous structure of wood is suggested

Hydrophobic composition based on mixed-molecular weight polyethylene

The paper presents investigations of compositions based on low and high molecular weight polyethylene so as to synthesize a hydrophobic composition for moisture protection of timber. X-ray phase analysis and measurements of the tear-off force of hydrophobic coating needed to apply to the timber surface and the limiting wetting angle are carried out to detect the hydrophobic, adhesive, electrophysical, and physicochemical properties of compositions. Kinetic dependencies are given for moisture absorption of timber specimens. It is shown that the preliminary formation of the texture by the surface patterning or its treatment with low-temperature plasma with the following protective coating results in the improvement of hydrophobic properties of the suggested compositions. These compositions can be used in the capacity of water repellents to protect building materials from moisture including restoration works

Quantitative Detection of the Influenza a Virus by an EGOFET-Based Portable Device

Elaboration of biosensors on the base of organic transistors with embedded biomolecules which can operate in an aqueous environment is of paramount importance. Electrolyte-gated organic field-effect transistors demonstrate high sensitivity in detection of various analytes. In this paper, we demonstrated the possibility of quantitative fast specific determination of virus particles by an aptasensor based on EGOFET. The sensitivity and selectivity of the devices were examined with the influenza A virus as well as with control bioliquids like influenza B, Newcastle disease viruses or allantoic fluid with different dilutions. The influence of the semiconducting layer thickness on EGOFETs sensory properties is discussed. The fabrication of a multi-flow cell that simultaneously registers the responses from several devices on the same substrate and the creation of a multi-sensor flow device are reported. The responses of the elaborated bioelectronic platform to the influenza A virus obtained with application of the portable multi-flow mode are well correlated with the responses obtained in the laboratory stationary mode

Water-repellent coatings for surface and 3D wood processing

The paper presents the results of research in organic chemical compositions for hydrophobic protection of wood with the use of surface and three-dimensional coating techniques of impregnation and chemical compositions. Water absorption indicators, angles of contact on the surface of treated samples are detected herein. Kinetic equation of the moisture diffusion transition in capillary-porous structure of wood is suggested

Highly sensitive detection of influenza virus with SERS aptasensor.

Highly sensitive and rapid technology of surface enhanced Raman scattering (SERS) was applied to create aptasensors for influenza virus detection. SERS achieves 106-109 times signal amplification, yielding excellent sensitivity, whereas aptamers to hemagglutinin provide a specific recognition of the influenza virus. Aptamer RHA0385 was demonstrated to have essentially broad strain-specificity toward both recombinant hemagglutinins and the whole viruses. To achieve high sensitivity, a sandwich of primary aptamers, influenza virus and secondary aptamers was assembled. Primary aptamers were attached to metal particles of a SERS substrate, and influenza viruses were captured and bound with secondary aptamers labelled with Raman-active molecules. The signal was affected by the concentration of both primary and secondary aptamers. The limit of detection was as low as 1 · 10-4 hemagglutination units per probe as tested for the H3N2 virus (A/England/42/72). Aptamer-based sensors provided recognition of various influenza viral strains, including H1, H3, and H5 hemagglutinin subtypes. Therefore, the aptasensors could be applied for fast and low-cost strain-independent determination of influenza viruses

Putative Mechanisms Underlying High Inhibitory Activities of Bimodular DNA Aptamers to Thrombin

Nucleic acid aptamers are prospective molecular recognizing elements. Similar to antibodies, aptamers are capable of providing specific recognition due to their spatial structure. However, the apparent simplicity of oligonucleotide folding is often elusive, as there is a balance between several conformations and, in some cases, oligomeric structures. This research is focused on establishing a thermodynamic background and the conformational heterogeneity of aptamers taking a series of thrombin DNA aptamers having G-quadruplex and duplex modules as an example. A series of aptamers with similar modular structures was characterized with spectroscopic and chromatographic techniques, providing examples of the conformational homogeneity of aptamers with high inhibitory activity, as well as a mixture of monomeric and oligomeric species for aptamers with low inhibitory activity. Thermodynamic parameters for aptamer unfolding were calculated, and their correlation with aptamer functional activity was found. Detailed analysis of thrombin complexes with G-quadruplex aptamers bound to exosite I revealed the similarity of the interfaces of aptamers with drastically different affinities to thrombin. It could be suggested that there are some events during complex formation that have a larger impact on the affinity than the states of initial and final macromolecules. Possible mechanisms of the complex formation and a role of the duplex module in the association process are discussed

Predictive value of vascular endothelial growth factor receptor type 2 in triple-negative breast cancer patients treated with neoadjuvant chemotherapy

The identification of informative biomarkers that could predict the treatment response is particularly important in the triple-negative (TN) breast cancer, which is characterized by biological diversity. The aim of this study was to investigate the impact of vascular endothelial growth factor receptor (VEGFR2) expression and its gene polymorphisms on pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) in Russian patients with TN breast cancer. We performed a retrospective analysis of 70 women with operable TN breast cancer, who underwent NCT with 5-fluorouracil, adriamycin, and cyclophosphamide (FAC) or cyclophosphamide, adriamycin, and capecitabine (CAX) between 2007 and 2013. VEGFR2 expression was evaluated before NCT by immunohistochemistry. TaqMan SNP assays were used for genotyping KDR − 604T>C (rs2071559) and KDR 1192G>A (rs2305948) polymorphisms. The pCR was used as an end-point in the treatment efficacy analysis. In the univariate analysis, the pCR rate was strongly associated with young age (P = 0.004), high Ki67 expression (P = 0.012), lymph node negativity (P = 0.023) as well as with positive VEGFR2 expression (P = 0.019) and the CAX regimen (P = 0.005). In the multivariate analysis, only patient’s age (P = 0.005) and pre-NCT VEGFR2 expression (P = 0.048) remained significant predictors of pCR. The pCR rate was higher in the CAX-treated patients than that in the FAC-treated patients (P = 0.005). Our results revealed that − 604TT genotype of rs2071559 and age < 50 years were correlated with a pCR in the CAX-treated patients. VEGFR2 expression in pre-NCT tumors and KDR gene polymorphism can be considered as additional predictive molecular markers of pCR in Russian TN breast cancer patients treated with NCT

Predictive value of vascular endothelial growth factor receptor type 2 in triple-negative breast cancer patients treated with neoadjuvant chemotherapy

The identification of informative biomarkers that could predict the treatment response is particularly important in the triple-negative (TN) breast cancer, which is characterized by biological diversity. The aim of this study was to investigate the impact of vascular endothelial growth factor receptor (VEGFR2) expression and its gene polymorphisms on pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) in Russian patients with TN breast cancer. We performed a retrospective analysis of 70 women with operable TN breast cancer, who underwent NCT with 5-fluorouracil, adriamycin, and cyclophosphamide (FAC) or cyclophosphamide, adriamycin, and capecitabine (CAX) between 2007 and 2013. VEGFR2 expression was evaluated before NCT by immunohistochemistry. TaqMan SNP assays were used for genotyping KDR − 604T>C (rs2071559) and KDR 1192G>A (rs2305948) polymorphisms. The pCR was used as an end-point in the treatment efficacy analysis. In the univariate analysis, the pCR rate was strongly associated with young age (P = 0.004), high Ki67 expression (P = 0.012), lymph node negativity (P = 0.023) as well as with positive VEGFR2 expression (P = 0.019) and the CAX regimen (P = 0.005). In the multivariate analysis, only patient’s age (P = 0.005) and pre-NCT VEGFR2 expression (P = 0.048) remained significant predictors of pCR. The pCR rate was higher in the CAX-treated patients than that in the FAC-treated patients (P = 0.005). Our results revealed that − 604TT genotype of rs2071559 and age < 50 years were correlated with a pCR in the CAX-treated patients. VEGFR2 expression in pre-NCT tumors and KDR gene polymorphism can be considered as additional predictive molecular markers of pCR in Russian TN breast cancer patients treated with NCT