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The use of targeted drug delivery systems, including those based on selective absorption by certain receptors on the surface of the target cell, can lead to a decrease in the minimum effective dose and the accompanying toxicity of the drug, as well as an increase in therapeutic efficacy. A fullerene C60 conjugate (FA-PVP-C60) with polyvinylpyrrolidone (PVP) as a biocompatible spacer and folic acid (FA) as a targeting ligand for tumor cells with increased expression of folate receptors (FR) was obtained. Using 13C NMR spectroscopy, FT-IR, UV-Vis spectrometry, fluorometry and thermal analysis, the formation of the conjugate was confirmed and the nature of the binding of its components was established. The average particle sizes of the conjugate in aqueous solutions and cell culture medium were determined using dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). The FA-PVP-C60 showed antiradical activity against •DPPH, •OH and O2•−, but at the same time, it was shown to generate 1O2. It was found that the conjugate in the studied concentration range (up to 200 μg/mL) is non-toxic in vitro and does not affect the cell cycle. To confirm the ability of the conjugate to selectively accumulate through folate-mediated endocytosis, its uptake into cells was analyzed by flow cytometry and confocal microscopy. It was shown that the conjugate is less absorbed by A549 cells with low FR expression than by HeLa, which has a high level of expression of this receptor. [ABSTRACT FROM AUTHOR]

The compressive sensing (CS) framework offers a cost-effective alternative to dense alias-free sampling. Designing seismic layouts based on the CS technique imposes the use of specific sampling patterns in addition to the logistical and geophysical requirements. We propose a two-step design process for generating CS-based schemes suitable for seismic applications. During the first step, uniform random sampling is used to generate a random scheme, which is supported theoretically by the restricted isometry property. Following that, designated samples are added to the random scheme to control the maximum distance between adjacent sources (or receivers). The null space property theoretically justifies the additional samples of the second step. Our sampling method generates sampling patterns with a CS theoretical background, controlled distance between adjacent samples, and a flexible number of active and omitted samples. The robustness of two-step sampling schemes for reallocated samples is investigated and CS reconstruction tests are performed. In addition, using this approach, a CS-based 3D seismic survey is designed, and the distributions of traces in fold maps and rose diagrams are analyzed. It is shown that the two-step scheme is suitable for CS-based seismic surveys and field applications. [ABSTRACT FROM AUTHOR]

Numerous studies of domestic and foreign researchers show that long-term exposure to electromagnetic fields (EMF) of artificial radio frequency range have negative effects on the human body. At the same time, if the effects of EMF of significant intensity are sufficiently well studied and regulated by the relevant sanitary norms and rules and state Standards, the harmful effects of low-intensity EMF are confirmed by many researchers, but there are practically no quantitative estimates of their impact on human health in combination with other exogenous and endogenous factors. In real conditions, the human body is often exposed to combined, combined and mixed EMF effects of various frequency ranges of different intensity, which cause a multiplicative effect, leading to an increased risk of occurrence and development of a number of socially significant diseases, especially when they are long-term exposure

Retinoid X receptors (RXRs), as members of the steroid/thyroid hormone superfamily of nuclear receptors, are crucial regulators of immune response during health and disease. RXR subtype expression is dependent on tissue and cell type, RXRα being the relevant isoform in monocytes and macrophages. Previous studies have assessed different functions of RXRs and positive implications of RXR agonists on outcomes after ischemic injuries have been described. However, the impact of a reduced Rxrα expression in mononuclear phagocytes on cardiac remodeling after myocardial infarction (MI) has not been investigated to date. Here, we use a temporally controlled deletion of Rxrα in monocytes and macrophages to determine its role in ischemia-reperfusion injury. We show that reduced expression of Rxrα in mononuclear phagocytes leads to a decreased phagocytic activity and an accumulation of apoptotic cells in the myocardium, reduces angiogenesis and cardiac macrophage proliferation in the infarct border zone/infarct area, and has an impact on monocyte/macrophage subset composition. These changes are associated with a greater myocardial defect 30 days after ischemia/reperfusion injury. Overall, the reduction of Rxrα levels in monocytes and macrophages negatively impacts cardiac remodeling after myocardial infarction. Thus, RXRα might represent a therapeutic target to regulate the immune response after MI in order to improve cardiac remodeling. [ABSTRACT FROM AUTHOR]

In this work the possibility of using the IR intensity of the stretching vibration νs of proton donor group for estimation of hydrogen bond strength was investigated. For a set of complexes with FH···X (X = F, N, O) hydrogen bonds in the wide range of energies (0.1–49.2 kcal/mol) vibrational frequencies νs and their intensities A were calculated (CCSD at complete basis set limit). The validity of the previously proposed linear proportionality between the intensification of the stretching vibration νs in IR spectra and hydrogen bond enthalpy –ΔH = 12.2 ∆A (A. V. Iogansen, Spectrochimica Acta A1999) was examined. It is shown that for a range of similar hydrogen bond types with complexation energies ∆E <15 kcal/mol the ∆E(∆A) function remains similar to that proposed in the Iogansen's work, while upon strengthening this dependency becomes significantly nonlinear. We examined two other parameters (∆Aνs and ∆A∙mR) related to IR intensity as descriptors of hydrogen bond strength which are proportional to transition dipole moment matrix element and mass‐independent dipole moment derivative. It was found that the dependency ∆E(∆Aνs) stays linear in the whole studied range of complexation energies and it can be used for evaluation of ∆E from infrared spectral data with the accuracy about 2 kcal/mol. The mass‐independent product ∆A∙mR is an appropriate descriptor for sets of complexes with various hydrogen bond types. Simple equations proposed in this work can be used for estimations of hydrogen bond strength in various systems, where experimental thermodynamic methods or direct calculations are difficult or even impossible. [ABSTRACT FROM AUTHOR]

Summary: Christodoulakis and Mamatzakis (2009, Journal of Applied Econometrics 24, pp. 583–606) estimate the EU Commission loss preferences for selected economic forecasts of 12 EU Member States. They employ the generalized method of moments (GMM) estimation procedure proposed by Elliott et al. (2005, Review of Economic Studies 72, pp. 1107–1125) and find the forecasts to be somewhat optimistic on average. However, this note shows the GMM estimator to possess nonstandard limiting distributions when some of the instruments are highly persistent, which is the case with one of the instruments employed by Christodoulakis and Mamatzakis. Standard distributions are recovered in some interesting particular cases which are relevant in practice. A reexamination of the EU Commission loss preferences using methods robust to persistence and a dataset extended to 2017 reveals that, while the conclusions of the original study are, by and large, still justified, the EU Commission loss preferences have become more symmetric over the whole studied period. [ABSTRACT FROM AUTHOR]