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Here we report on the structural and tribo-mechanical characterization of epitaxial single-crystalline Ti2AlC MAX phase thin films, grown by means of electron beam physical vapor deposition at relatively low temperature (700°C). The growth of phase pure Ti2AlC at a relatively lower temperature when compared to other PVD methods was achieved utilizing a relatively low deposition rate and layer-by-layer deposition technique. The epitaxial growth is evidenced through the combination of XRD, HR-TEM and Raman spectroscopy measurements. The nanomechanical and micro-scale tribological properties of the Ti2AlC thin films were studied by means of nanoindentation and nanoscratch tests. The growth temperature of phase pure single-crystalline Ti2AlC MAX phase thin films was reduced to 700°C utilizing the low-rate layer-by-layer PVD technique. [ABSTRACT FROM AUTHOR]

Low temperature scanning tunneling microscopy/ scanning tunneling spectroscopy, room temperature atomic force microscopy and X-ray photoelectron spectroscopy of the boron ions implanted into the magnesium substrate were performed in order to get information about the local superconducting behavior of thin MgBx film. Results confirm the island superconductivity far from the percolation threshold of the bulk superconducting MgB2 sample. [ABSTRACT FROM AUTHOR]

Epicardial adipose tissue (EAT) is a fat deposit surrounding the heart and located under the visceral layer of the pericardium. Due to its unique features, the contribution of EAT to the pathogenesis of cardiovascular and metabolic disorders is extensively studied. Especially, EAT can be associated with the onset and development of coronary artery disease, myocardial infarction and post-infarct heart failure which all are significant problems for public health. In this article, we focus on the mechanisms of how EAT impacts acute coronary syndromes. Particular emphasis was placed on the role of inflammation and adipokines secreted by EAT. Moreover, we present how EAT affects the remodeling of the heart following myocardial infarction. We further review the role of EAT as a source of stem cells for cardiac regeneration. In addition, we describe the imaging assessment of EAT, its prognostic value, and its correlation with the clinical characteristics of patients.

Currently marketed drug-eluting stents are non-selective in their anti-restenotic action. New active substance introduction to polymeric stents and vascular grafts can promote early re-endothelialization, crucial in preventing implant restenosis. Additionally, managing material hydrophobicity by blending synthetic polymers limits adverse effects on bulk properties and controls active substance release. However, the influence of hydrophilic synthetic polymer on human cells in the cardiovascular system remains to be determined. In this report, effects of both poly(ε-caprolactone) (PCL) fibers hydrophilization with Pluronic P123 (P123) and cilostazol (CIL) loading were studied. Physicochemical and mechanical properties of electrospun tubular structures produced from PCL and PCL/P123 fibers with and without CIL were investigated and compared. Release profiles studies and in vitro cell proliferation assays of electrospun materials were conducted. It was found that P123 located near the surface of electrospun fibers increased the rate of CIL release. PCL formulation sustained human umbilical vein endothelial cells (HUVEC) growth for 48 h. Despite improved hydrophilicity, PCL/P123 formulations were found to reduce HUVEC viability. Both PCL and PCL/P123 materials reduced primary aortic smooth muscle cells (PASM) viability after 48 h. In PCL formulations containing CIL, drug release caused a decrease in PASM viability. P123 blending with PCL was found to be as a useful pre-fabrication technique for modulating surface hydrophobicity of electrospun materials and the release profile of incorporated active substance. The cytotoxicity of P123 was evaluated to improve the design of drug-loaded vascular grafts for cardiovascular applications., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Reduced graphene oxide-magnetite hybrid aerogels attract great interest thanks to their potential applications, e.g., as magnetic actuators. However, the tendency of magnetite particles to migrate within the matrix and, ultimately, escape from the aerogel structure, remains a technological challenge. In this article we show that coating magnetite particles with polydopamine anchors them on graphene oxide defects, immobilizing the particles in the matrix and, at the same time, improving the aerogel structure. Polydopamine coating does not affect the magnetic properties of magnetite particles, making the fabricated materials promising for industrial applications.

The Review of Four Experimental Methods: X-ray diffraction, Raman spectroscopy, electron paramagnetic resonance and four-point electrical conductivity measurements is presented to characterize carbon nanoparticles. Two types of carbon nanoparticle systems are discussed: one comprising the powder of individual carbon nanoparticles and the second as a structurally interconnected nanoparticle matrix in the form of a fiber. X-ray diffraction and Raman spectroscopy reveal the atomic structure of the carbon nanoparticles and allow for observation of the changes in the quasi-graphitic ordering induced by ultrasonic irradiation and with the so-called quasi-high pressure effect under adsorption conditions. Structural changes have strong influence on the electronic properties, especially the localization of charge carriers within the nanoparticles, which can be observed with the EPR technique. This in turn can be well-correlated with the four-point electrical conductivity measurements which directly show the character of the charge carrier transport within the examined structures.

We report X-ray diffraction studies of water and carbon tetrachloride adsorbed in nanoporous activated carbon fibres. The fibres are built of turbostratic nanoparticles separated by quasi two-dimensional voids, forming narrow slit-shaped pores. In order to determine the structure of water within the pores and its influence on the fibres' structure, mean interatomic and intermolecular distances have been estimated from the positions of the maxima of the normalized angular distribution functions obtained by X-ray diffraction. We observe a cluster arrangement of the water molecules, as well as significant changes in the interlayer distance of the carbon nanoparticles upon adsorption of both water and carbon tetrachloride. The results suggest that very high pressures arise within the pores, as has been observed in molecular simulations, and this may give rise to the large change in electronic properties of the fibres after adsorption of guest molecules. The in-pore pressure normal to the pore walls is estimated from the experimental data, and is found to be positive and of the order 4000 bar. Molecular simulation results for the normal pressure component are presented for both water and carbon tetrachloride in carbon slit pores, and are in general agreement with the experiments. For both fluids the normal pressure is an oscillating function of pore width.

Among several topoisomerase I inhibitors topotecan is worth taking into account because of its little toxicity, good tolerance and quick excretion. The study compared functioning of bone marrow, liver and kidneys during and after the treatment, as well as survival period and quality of life of patients treated with topotecan and patients who underwent symptomatic treatment. 35 patients aged 43-71 of both sexes, with advanced stage of large intestine cancer (IV grade in TNM scale) were included in the study. 20 hospitalized patients were administered topotecan, topoisomerase I inhibitor, intravenously in 5-day courses (1.5 mg/m2 of body surface daily) repeated 5 times with 21-day intervals. Before the beginning of therapy and after it the following were conducted: medical check-ups as well as surveys and test research including groups of somatic and vegetative symptoms connected with the disease (based on the questionnaire QLQ-C30). 15 patients with the similar stage of the disease who had not agreed to palliative treatment with chemotherapy were treated only symptomatically. Applying antineoplastic treatment with topotecan contributes to the extension of the survival time by 4 months on average, and mortality during and after the treatment is lower than in the group of patients with the symptomatic treatment only. Antineoplastic treatment improves the quality of life and delays the disease progression. The quality of life is better until the preterminal period of the disease and enables patients maintaining motor activity and independence.

Unlabelled: Anxiety accompanies patients at all stages of severe somatic diseases as well in the course of diagnostic procedures. It affects significantly quality of life of these patients and their relations with their physicians. It may also induce or exacerbate wide range of somatic complaints., Objective: Evaluation of usefulness of anxiolytic therapies in patients with diagnosed neoplastic diseases. Comparison of anti-anxiety and antidepressant effects of alprazolam and diazepam in patients treated with systemic chemotherapy., Material and Methods: Final analysis included 45 patients with various malignancies randomly assigned to receive alprazolam 3 x 0.5 mg or diazepam 3 x 2 mg. Anti-anxiety effects of both drugs was evaluated four times during the 21-day follow-up period at one week intervals with help of Clinical Global Impression scale (CGI), Hamilton Anxiety Rating Scale (HARS), Hospital Anxiety and Depression Scale (HADS). Analysis of these questionnaires was performed with Mann-Whitney test and Wilcoxon test., Results: Statistically significant reduction of anxiety was found in both study groups. Alprazolam was proven to be significantly more effective than diazepam in reduction of anxiety (HARS, HADS) and depressive symptoms accompanying anxiety (HADS). Alprazolam vs. diazepam showed better tolerance by patients., Conclusions: Alprazolam effectively reduced anxiety in patients suffering from malignant diseases. Alprazolam was found to reduce depressive symptoms in patients with neurotic disorders whereas no effects of this kind were observed for diazepam.