Collagen type II modification by hypochlorite

Oxidation of proteins is a common phenomenon in the inflammatory process mediated by highly reactive agents such as hypochlorite (HOCl/OCl-) produced by activated neutrophils. For instance, in rheumatoid arthritis hypochlorite plays an important role in joint destruction. One of the major targets for HOCl/OCl- is collagen type II (CII) - the primary cartilage protein. In our study, HOCl/OCl- mediated collagen II modifications were tested using various methods: circular dichroism (CD), HPLC, ELISA, dynamic light scattering (DLS), fluorimetry and spectrophotometry. It was shown that hypochlorite action causes deamination with consecutive carbonyl group formation and transformation of tyrosine residues to dichlorotyrosine. Moreover, it was shown that ammonium chloramine (NH2Cl) formed in the reaction mixture reacts with CII. However, in this case the yield of carbonyl groups and dichlorotyrosine is lower than that observed for HOCl/OCl- by 50%. CD data revealed that collagen II exists as a random coil in the samples and that chlorination is followed by CII fragmentation. In the range of low HOCl/OCl- concentrations (up to 1 mM) 10-90 kDa peptides are predominant whereas massive production of shorter peptides was observed for high (5 mM) hypochlorite concentration. DLS measurements showed that chlorination with HOCl/OCl- decreases the radius of collagen II aggregates from 30 to 6.8 nm. Taking into account the fact that chlorinated collagen is partially degraded, the DLS results suggest that smaller micelles are formed of the 10-90 kDa peptide fraction. Moreover, collagen chlorination results in epitope modification which affects CII recognition by anti-CII antibodies. Finally, since in the synovial fluid the plausible hypochlorite concentration is smaller than that used in the model the change of size of molecular aggregates seems to be the best marker of hypochlorite-mediated collagen oxidation

Gender, Body Image and Social Support: Biopsychosocial Deter-minants of Depression Among Patients with Psoriasis

The aim of this study was to examine the importance of psychosocial factors, such as emotional and instrumental social support, distress, and assumptions about appearance and its salience to one’s self-worth, and to relate these factors to depressive symptoms in patients with psoriasis, according to gender. A group of 219 patients with psoriasis, aged 18-70 years completed the Beck Depression Inventory, the Appearance Schemas Inventory-Revised, the Berlin Social Support Scales, and the Distress Thermometer. Body Surface Area index was used to assess the severity of psoriasis. The main contributors to depression were: female gender, beliefs about appearance and its salience to one’s self-worth, greater psychological distress, and lower levels of emotional social support. Therefore, improving the body image of patients with psoriasis, by reducing its salience in their personal lives, may play a role in the prevention of depression, especially in women

Location-Based Games as a Contemporary, Original, and Innovative Method of Seniors’ Teaching and Learning

This book is a result of the Location-based games as a contemporary, original, and innovative method of seniors’ teaching and learning [LoGaSET] project, coordinated by Foundation Pro Scientia Publica, financed from the Erasmus Plus KA2 strategic partnership budget (nr 2017-1-PL01-KA204-038869). Dr Ewa Jurczyk-Romanowska (University of Wrocław, Poland) was the scientific coordinator of the project