Pathogenetic role of cytokines in hemorrhagic fever with renal syndrome in dynamics and disease of various severity

The aim of the work is to determine the relationship between the levels of cytokines of proinflammatory and anti-inflammatory action during the clinical course of hemorrhagic fever with renal syndrome (HFRS) and the previously described characteristics of the phenotypic composition of blood lymphocytes in disease of various severity. Materials and methods. 65 patients with a serologically verified diagnosis of HFRS were under observation. The control group included 15 conditionally healthy people. Determination of cytokines in the blood of patients with HFRS was carried out by the enzyme immunoassay method at the different stages of the disease. The phenotypic composition of blood lymphocytes was assessed by flow cytofluorimetry. Results. At the different stages of the disease, there was a quantitatively different increase in the content of cytokines in the blood associated with cytotoxic immune reactions (IL-12, IFN, TNFa, TNF), as well as IL-10 and IL-6 correlated with each other in severe cases, against the background of a drop in blood levels of IL-4 and IL-1. In the moderate course of HFRS, correlations of IL-12 and IL-4 with NKG2D+ CTL, the relationship of IL-12 with almost all other cytokines, and the correlation of CD8+ Treg with IL-6 and TNF levels were observed. In severe cases, the formation of a complex that included interconnected IL-6 and IL-10 correlating with the number of NKG2D+ CTL, CD8+ Treg, NKT was noted. Conclusion. The pathogenetically significant mechanism of HFRS is realized with the predominant participation of cytokines of the cellular immune response and IL-6, correlatively associated with NKG2D+ CTL, CD8+ Treg, NKT, which, in case of a favorable outcome, contribute to the active formation of a pool of CD8+ memory cells, disrupted presumably by excessive secretion of IL-10

Performance of the left ventricular myocardium in patients with a negative test result during exercise stress echocardiography

Aim. To determine the possibility of identifying patients with significant coronary artery disease (CAD) by evaluation of the left ventricular (LV) myocardial work indicators by constructing pressure-strain loops despite a negative test result during exercise stress echocardiography. Materials and methods. The study included 79 patients with suspected or previously confirmed CAD, of which 47 (59%) men, who had a negative test result during exercise stress echocardiography on the treadmill. Global work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE) were evaluated using the technique of constructing pressure-strain loops at rest and at peak exercise. Results. With similar systolic blood pressure and LV ejection fraction at peak exercise between the control group and the group of patients with single-vessel CAD, there was revealed significant difference in GWI, GCW and GWE at peak exercise. In patients with multi-vessel CAD, GWI and GCW also significantly differed from the control group at peak exercise. Conclusion. The evaluation of LV myocardial work indicators may be recommended for a more accurate diagnosis of CAD in negative or unreliable test results during exercise stress echocardiography

Superconformal mechanics and nonlinear supersymmetry

We show that a simple change of the classical boson-fermion coupling constant, $2\alpha \to 2\alpha n$, $n\in \N$, in the superconformal mechanics model gives rise to a radical change of a symmetry: the modified classical and quantum systems are characterized by the nonlinear superconformal symmetry. It is generated by the four bosonic integrals which form the so(1,2) x u(1) subalgebra, and by the 2(n+1) fermionic integrals constituting the two spin-n/2 so(1,2)-representations and anticommuting for the order n polynomials of the even generators. We find that the modified quantum system with an integer value of the parameter $\alpha$ is described simultaneously by the two nonlinear superconformal symmetries of the orders relatively shifted in odd number. For the original quantum model with $|\alpha|=p$, $p\in \N$, this means the presence of the order 2p nonlinear superconformal symmetry in addition to the osp(2|2) supersymmetry.Comment: 16 pages; misprints corrected, note and ref added, to appear in JHE

Latitude, temperature, and habitat complexity predict predation pressure in eelgrass beds across the Northern Hemisphere

Latitudinal gradients in species interactions are widely cited as potential causes or consequences of global patterns of biodiversity. However, mechanistic studies documenting changes in interactions across broad geographic ranges are limited. We surveyed predation intensity on common prey (live amphipods and gastropods) in communities of eelgrass (Zostera marina) at 48 sites across its Northern Hemisphere range, encompassing over 370 of latitude and four continental coastlines. Predation on amphipods declined with latitude on all coasts but declined more strongly along western ocean margins where temperature gradients are steeper. Whereas in situ water temperature at the time of the experiments was uncorrelated with predation, mean annual temperature strongly positively predicted predation, suggesting a more complex mechanism than simple increased metabolic activity at the time of predation. This large-scale biogeographic pattern was modified by local habitat characteristics; predation declined with higher shoot density both among and within sites. Predation rates on gastropods, by contrast, were uniformly low and varied little among sites. The high replication and geographic extent of our study not only provides additional evidence to support biogeographic variation in intensity, but also insight into the mechanisms that relate temperature and biogeographic gradients in species interactions

Finite-gap systems, tri-supersymmetry and self-isospectrality

We show that an n-gap periodic quantum system with parity-even smooth potential admits $2^n-1$ isospectral super-extensions. Each is described by a tri-supersymmetry that originates from a higher-order differential operator of the Lax pair and two-term nonsingular decompositions of it; its local part corresponds to a spontaneously partially broken centrally extended nonlinear N=4 supersymmetry. We conjecture that any finite-gap system having antiperiodic singlet states admits a self-isospectral tri-supersymmetric extension with the partner potential to be the original one translated for a half-period. Applying the theory to a broad class of finite-gap elliptic systems described by a two-parametric associated Lame equation, our conjecture is supported by the explicit construction of the self-isospectral tri-supersymmetric pairs. We find that the spontaneously broken tri-supersymmetry of the self-isospectral periodic system is recovered in the infinite period limit.Comment: 40 pages, published versio

A Pleistocene legacy structures variation in modern seagrass ecosystems

Distribution of Earth’s biomes is structured by the match between climate and plant traits, which in turn shape associated communities and ecosystem processes and services. However, that climate–trait match can be disrupted by historical events, with lasting ecosystem impacts. As Earth’s environment changes faster than at any time in human history, critical questions are whether and how organismal traits and ecosystems can adjust to altered conditions. We quantified the relative importance of current environmental forcing versus evolutionary history in shaping the growth form (stature and biomass) and associated community of eelgrass ( Zostera marina ), a widespread foundation plant of marine ecosystems along Northern Hemisphere coastlines, which experienced major shifts in distribution and genetic composition during the Pleistocene. We found that eelgrass stature and biomass retain a legacy of the Pleistocene colonization of the Atlantic from the ancestral Pacific range and of more recent within-basin bottlenecks and genetic differentiation. This evolutionary legacy in turn influences the biomass of associated algae and invertebrates that fuel coastal food webs, with effects comparable to or stronger than effects of current environmental forcing. Such historical lags in phenotypic acclimatization may constrain ecosystem adjustments to rapid anthropogenic climate change, thus altering predictions about the future functioning of ecosystems