Cytokine concentration and profile of lipid peroxidation in synovial fluids of patients with osteoarthritis and concomitant defects of articular surfaces

The objective of the study was to evaluate cytokine concentration and profile of lipid peroxidation in synovial fluid of patients with osteoarthritis and concomitant defects of articular surfaces. Material and methods Synovial fluid samples were taken from 102 patients with osteoarthritis of the knee joint. Patients with rheumatoid arthritis, osteoarthritis of a post-traumatic etiology, and somatic diseases that could affect results of the study were excluded from the study. Thirty control samples originated from deceased donors of both genders. Synovial fluid was extracted in compliance with Ministry of Health Order No. 694 dtd July 21, 1978, p. 2.24 "Guidelines of forensic medical examination in the USSR". Results Findings of laboratory studies showed statistically significant differences in synovial fluid cytokine levels depending on absence or presence of defects on the tibial condyles. Biochemical tests revealed greater changes in lipid peroxidation in patients with articular defects. Total level of lipid peroxidation products resulting in the formation of conjugated dienes (CD), malondialdehyde (MDA) was shown to increase in both groups of patients being significantly higher in patients with defects on articular surfaces. Primary (conjugated dienes) and secondary (malondialdehyde) lipid peroxidation products accumulated in the synovial fluid of the patients with the levels being significantly increased in both groups with no changes in the CD/MDA ratio. Patients with defects on articular surfaces demonstrated increased formation of primary products, and non-defect group showed greater formation of secondary products. Antioxidant enzyme, catalase, appeared to me more active in patients of Group I. Conclusion The findings can be used to evaluate defects on articular surface and identify strategies of medication therapy

Normative resistance to responsibility to protect in times of emerging multipolarity: the cases of Brazil and Russia

This article assesses the normative resistance to Responsibility to Protect adopted by Brazil and Russia against the backdrop of their international identities and self-assigned roles in a changing global order. Drawing upon the framework of Bloomsfield's norm dynamics role spectrum, it argues that while the ambiguous Russian role regarding this principle represents an example of 'norm antipreneurship', particularities of Brazil's resistance are better grasped by a new category left unaccounted for by this model, which this study portrays as 'contesting entrepreneur'.- (undefined

Contemporary Research and Developments in the Low-Toxic Chelating Reagents for the Extraction of Non-Ferrous and Noble Metals from Poor Polymetallic Ores and Processing Tailings

An urgent technological, economic and environmental task of mining and metallurgical enterprises is to involve poor, off-balance and hard-to-beneficiate ores in the technological process, as well as accumulated and current waste from mining and metallurgical industries. As the reserves of developed deposits are depleted, technogenic objects may become a priority, and in some cases the only, source of mineral raw materials. Mining wastes represent a large reserve of raw materials for the extraction of non-ferrous and precious metals, and at the same time, they are centers of local or regional environmental pollution. Stale waste re-processing may promote territorial cultivation and reduce the environmental burden. The conventional methods of poor ore and waste treatment do not fully provide for a sufficient separation degree of high metal extraction, and lead to significant valuable ore losses, while the quality of the obtained concentrates often does not meet the requirements for subsequent technological process. In this regard, the development of novel chelating agents with specific functional groups that can selectively adsorb on the mineral surface, change the contrast of chemical surface composition and improve the flotation properties of mineral complexes, is an innovative solution for increasing their flotation selectivity. Furthermore, the synthesis and application of novel flotation reagents may help to replace toxic reagents by ecologically friendly or less-toxic ones

TNFR1 Absence Is Not Crucial for Different Types of Cell Reaction to TNF: A Study of the TNFR1-Knockout Cell Model

Background: One of the mechanisms regulating the biological activity of tumor necrosis factor (TNF) in cells is the co-expression of TNFR1/TNFR2 receptors. A model with a differential level of receptor expression is required to evaluate the contribution of these mechanisms. Aim: The development of a cellular model to compare the effects of TNF on cells depending on the presence of both receptors and TNFR2 alone. Methods: TNFR1 absence modifications of ZR-75/1 and K-562 cell lines were obtained by TNFR1 knockout. The presence of deletions was confirmed by Sanger sequencing, and the absence of cell membrane receptor expression was confirmed by flow cytometry. The dose-dependent effect of TNF on intact and knockout cells was comparatively evaluated by the effect on the cell cycle, the type of cell death, and the profile of expressed genes. Results: Knockout of TNFR1 resulted in a redistribution of TNFR2 receptors with an increased proportion of TNFR2+ cells in both lines and a multidirectional change in the density of expression in the lines (increased in K562 and decreased in ZR75/1). The presence of a large number of cells with high TNFR2 density in the absence of TNFR1 in the K562 cells was associated with greater sensitivity to TNF-stimulating doses and increased proliferation but did not result in a significant change in cell death parameters. A twofold increase in TNFR2+ cell distribution in this cell line at a reduced expression density in ZR75/1 cells was associated with a change in sensitivity to low cytokine concentrations in terms of proliferation; an overall increase in cell death, most pronounced at standard stimulating concentrations; and increased expression of the lymphocyte-activation gene groups, host–pathogen interaction, and innate immunity. Conclusions: The absence of TNFR1 leads to different variants of compensatory redistribution of TNFR2 in cellular models, which affects the type of cell response and the threshold level of sensitivity. The directionality of cytokine action modulation and sensitivity to TNF levels depends not only on the fraction of cells expressing TNFR2 but also on the density of expression