Granulysin expression and granulysin-mediated apoptosis in the peripheral blood of osteoarthritis patients.

Osteoarthritis (OA) is a chronic joint disease caused by mechanical damage and metabolic factors that support the development of low-grade inflammation. Increased levels of T helper 1 pro-inflammatory cytokines in the serum of OA patients may support granulysin (GNLY) mediated cytotoxicity, which in-turn may contribute to the pathogenesis of OA. In the present study, GNLY expression and cytotoxic/apoptotic mechanisms mediated by GNLY in the peripheral blood of OA patients were assessed. A total of 40 non-obese women (median age of 64 years old) with knee OA, and 40 controls (median age 62 years old) were enrolled in the study. GNLY, IFN-γ and IL-4 expression levels were investigated in peripheral blood lymphocytes (PBLs) using flow cytometry, immunocytochemistry and/or confocal microscopy. Natural killer (NK) GNLY-mediated apoptosis through NK effectors against K-562 targets was analyzed using the PKH-26 18-h cytotoxicity assay. Serum GNLY levels were assessed using ELISA. The percentage of GNLY+PBLs was higher in the OA patients than that in the controls due to the increase in the proportions of GNLY+ cells in the natural killer (NK), T and natural killer T (NKT) subsets. GNLY localization inside exocytotic lysosomal-associated membrane protein-1+ granules was ~40% in both groups. However, the intensity of GNLY labeling in PBLs was higher in OA patients than in the controls, and it was supported by the increased expression of IFN-γ relative to IL-4 in NK and T cells from OA patients. The serum GNLY concentration was <0.3 ng/ml in both groups. RC8 anti-GNLY mAb by itself was unable to significantly alter early apoptosis, whereas RC8 anti-GNLY mAb combined with anti-perforin mAb significantly reduced NK-mediated early apoptosis of K-562 targets in the OA patients, whilst not exerting a notable effect in the controls. Anti-perforin mAb by itself did not affect apoptosis significantly. These results suggest that in women with knee OA, GNLY expression in the PBL subsets and GNLY-mediated early apoptosis of K-562 targets are increased compared with the controls and accompanied by intracellular dominance of IFN-γ over IL-4 in NK cells.

The impact of the COVID-19 pandemic on resident physicians: A cross-sectional study.

BACKGROUND: COVID-19 presents a threat to the mental health of the medical staff working with COVID-19 patients. OBJECTIVE: To investigate the impact of working during the COVID-19 pandemic on resident physicians. METHODS: The study was conducted via anonymous online survey and included resident physicians. The survey contained questions about sociodemographic information, general job satisfaction during the COVID-19 pandemic, and the impact of the COVID-19 pandemic on their personal lives. RESULTS: This study included a response from 728 resident physicians. The majority of residents rated that the COVID-19 pandemic had a mostly negative impact on their satisfaction with professional life (59.9%) and quality of work (62.8%), their personal lives (44.7%) and quality of life (57.1%). Half of all residents indicated that they did not have enough personal protective equipment (PPE). About one-third of residents indicated that the level of stress at work during the COVID-19 pandemic was higher. CONCLUSIONS: Working as resident physicians during COVID-19 pandemic had a negative effect on participants' professional and personal lives. Residents did not have all the necessary PPE nor felt safe working with patients with suspected or proven COVID-19. Further action is needed to provide support for physician residents working during the COVID-19 pandemic.

Can pain intensity in osteoarthritis joint be indicator of the impairment of endothelial function?

We propose that pathological remodeling in joint tissues of osteoarthritis (OA) patients persistently stimulates local secretion of pro-inflammatory mediators, which overflow into the blood, activating leukocytes that impair endothelial function and accelerate the atherosclerotic process. During periods of pain, endothelial dysfunction progresses more aggressively due to elevated secretion of these pro-inflammatory mediators, which are involved in both atherosclerosis and the sensation of pain. Concentrations of pro-inflammatory cytokines and their antagonists, activating and decoy receptors of the broad interleukin (IL)-1 and IL-17 families, IL-15, and monocyte chemotactic protein-1 should be measured in peripheral blood samples of OA patients and compared with (I) OA clinical severity; (II) subclinical parameters of atherosclerosis; (III) ischemic heart disease risk factors; (IV) soluble factors indicating endothelial dysfunction; (V) degree of bone destruction; and (VI) results of a six-minute walk test. Arthroscopy and joint replacement surgery provide an opportunity to estimate mRNA and protein expression of inflammatory mediators in specimens of synovial fluid, synovial membrane, cartilage, and/or subarticular bone. A range of methods, including questionnaires, X-ray, computed tomography, ultrasound, enzyme-linked immunosorbent assay, immunohistology, immunofluorescence, and reverse transcription and in situ polymerase chain reaction are available. Understanding the inflammatory and immune mechanisms underlying OA may allow the early identification of patients at high risk of cardiovascular disease, independently of classical coronary risk factors. Pain may constitute an extrinsic indicator of currently worsening endothelial function.