249 research outputs found
Generation of orbital-angular-momentum-entangled biphotons in triangular quadratic waveguide arrays
We suggest that closed-loop quadratic nonlinear waveguide arrays can be used as a compact interferometrically stable integrated source of discrete orbital-angular-momentum (OAM) entangled biphoton state. We describe analytically and numerically the proce
The association of TNF-alpha secretion and mtDNA copy number in CD14+ monocytes of patients with obesity and CHD
IntroductionMitochondrial dysfunction may be one of the causes of inflammatory activation of monocytes and macrophages, which leads to excessive secretion of inflammatory mediators and the development of chronic inflammation.AimsThe study was aimed to evaluate the secretion of inflammatory cytokine tumor necrosis factor-α (TNF-α) in the primary culture of monocytes, and to analyze its relationship with the number of mitochondrial DNA (mtDNA) copies in the blood of patients with coronary heart disease (CHD) and obesity.Materials and methods108 patients with obesity and concomitant CHD and a control group of 25 participants were included in the study. CD14+ monocytes were isolated by a standard method in a ficoll-urographin gradient, followed by separation using magnetic particles. The number of mtDNA copies was estimated using qPCR.ResultsIt was demonstrated that the number of mtDNA copies was significantly increased in groups of patients with CHD and obesity + CHD in comparison with control group. mtDNA copy number positively correlated with basal and LPS-stimulated TNF-α secretion, the most significant correlation was found in the group of patients with CHD and obesity.ConclusionThus, the change in mtDNA copy number in CD14+ monocytes which indicates the presence of mitochondrial dysfunction, confirm the direct involvement of mitochondria in the violation of the inflammatory response of monocytes revealed in this study as an increased secretion of inflammatory cytokine TNF-α
Modulation of the pHLIP Transmembrane Helix Insertion Pathway
The membrane-associated folding/unfolding of pH (low) insertion peptide (pHLIP) provides an opportunity to study how sequence variations influence the kinetics and pathway of peptide insertion into bilayers. Here, we present the results of steady-state and kinetics investigations of several pHLIP variants with different numbers of charged residues, with attached polar cargoes at the peptide\u27s membrane-inserting end, and with three single-Trp variants placed at the beginning, middle, and end of the transmembrane helix. Each pHLIP variant exhibits a pH-dependent interaction with a lipid bilayer. Although the number of protonatable residues at the inserting end does not affect the ultimate formation of helical structure across a membrane, it correlates with the time for peptide insertion, the number of intermediate states on the folding pathway, and the rates of unfolding and exit. The presence of polar cargoes at the peptide\u27s inserting end leads to the appearance of intermediate states on the insertion pathway. Cargo polarity correlates with a decrease of the insertion rate. We conclude that the existence of intermediate states on the folding and unfolding pathways is not mandatory and, in the simple case of a polypeptide with a noncharged and nonpolar inserting end, the folding and unfolding appears as an all-or-none transition. We propose a model for membrane-associated insertion/folding and exit/unfolding and discuss the importance of these observations for the design of new delivery agents for direct translocation of polar therapeutic and diagnostic cargo molecules across cellular membranes
Atheroprotective Effects of Glycyrrhiza glabra L.
Cardiovascular diseases associated with atherosclerosis are the major cause of death in developed countries. Early prevention and treatment of atherosclerosis are considered to be an important aspect of the therapy of cardiovascular disease. Preparations based on natural products affect the main pathogenetic steps of atherogenesis, and so represent a perspective for the long-term prevention of atherosclerosis development. Numerous experimental and clinical studies have demonstrated the multiple beneficial effects of licorice and its bioactive compounds—anti-inflammatory, anti-cytokine, antioxidant, anti-atherogenic, and anti-platelet action—which allow us to consider licorice as a promising atheroprotective agent. In this review, we summarized the current knowledge on the licorice anti-atherosclerotic mechanisms of action based on the results of experimental studies, including the results of the in vitro study demonstrating licorice effect on the ability of blood serum to reduce intracellular cholesterol accumulation in cultured macrophages, and presented the results of clinical studies confirming the ameliorating activity of licorice in regard to traditional cardiovascular risk factors as well as the direct anti-atherosclerotic effect of licorice
The Role of Cytokines in Cholesterol Accumulation in Cells and Atherosclerosis Progression
Atherosclerosis is the most common cardiovascular disease and is the number one cause of death worldwide. Today, atherosclerosis is a multifactorial chronic inflammatory disease with an autoimmune component, accompanied by the accumulation of cholesterol in the vessel wall and the formation of atherosclerotic plaques, endothelial dysfunction, and chronic inflammation. In the process of accumulation of atherogenic lipids, cells of the immune system, such as monocytes, macrophages, dendritic cells, etc., play an important role, producing and/or activating the production of various cytokines—interferons, interleukins, chemokines. In this review, we have tried to summarize the most important cytokines involved in the processes of atherogenesis
STRUCTURE AND PROPERTIES OF FINE-GRAINED Zn-Mg ALLOYS FOR MEDICAL PURPOSES
В работе исследовано влияние условий отливки слитка на структуру и свойства бинарных модельных Zn-Mg сплавов. Установлено, что за счет изменения величины переохлаждения на фронте кристаллизации происходит уменьшение объемной доли эвтектики ((Zn) + Mg2Zn) и измельчение зёренной структуры сплавов в 3-5 раз. Показано, что увеличение содержания Mg в сплаве также способствует измельчению зеренной структуры и увеличению твердости сплавов. Выявлено, что твердость исследованных образцов в большей степени определяется объемной долей эвтектики, а не дисперсностью зеренной структуры сплавов.The influence of ingot casting conditions on the structure and properties of binary model Zn-Mg alloys is investigated. It was found that due to the different magnitude of supercooling at the crystallization front, the volume fraction of eutectic ((Zn) + Mg2Zn) and the alloys grain sizes decreased. It is shown that an Mg content increase in the alloy also provided the grinding of the grain structure and an increase in the alloys hardness. It is revealed that the samples hardness is determined to a greater extent by the volume fraction of the eutectic, and not by the dispersion of the alloys grain structure
Invasive Plants and Enemy Release: Evolution of Trait Means and Trait Correlations in Ulex europaeus
Several hypotheses that attempt to explain invasive processes are based on the fact that plants have been introduced without their natural enemies. Among them, the EICA (Evolution of Increased Competitive Ability) hypothesis is the most influential. It states that, due to enemy release, exotic plants evolve a shift in resource allocation from defence to reproduction or growth. In the native range of the invasive species Ulex europaeus, traits involved in reproduction and growth have been shown to be highly variable and genetically correlated. Thus, in order to explore the joint evolution of life history traits and susceptibility to seed predation in this species, we investigated changes in both trait means and trait correlations. To do so, we compared plants from native and invaded regions grown in a common garden. According to the expectations of the EICA hypothesis, we observed an increase in seedling height. However, there was little change in other trait means. By contrast, correlations exhibited a clear pattern: the correlations between life history traits and infestation rate by seed predators were always weaker in the invaded range than in the native range. In U. europaeus, the role of enemy release in shaping life history traits thus appeared to imply trait correlations rather than trait means. In the invaded regions studied, the correlations involving infestation rates and key life history traits such as flowering phenology, growth and pod density were reduced, enabling more independent evolution of these key traits and potentially facilitating local adaptation to a wide range of environments. These results led us to hypothesise that a relaxation of genetic correlations may be implied in the expansion of invasive species
Search for top squark pair production in pp collisions at root s=13 TeV using single lepton events
Peer reviewe
Multiplicity and rapidity dependence of strange hadron production in pp, pPb, and PbPb collisions at the LHC
Peer reviewe
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