Impaired Dynamic Thiol%252Fdisulfide Homeostasis and Pro-inflammatory Parameters in Hand Osteoarthritis

Background%253A Reactive oxygen species have a role in pathogenesis of osteoarthritis. The main objective of this study was to determine other oxidant%252Fantioxidant substances and inflammatory markers in hand osteoarthritis patients. Methods%253A Thirty healthy controls and 50 patients with hand osteoarthritis (HOA) were included in the study. All patients were questioned about age, sex, history of the symptoms, presence of sensitive and swollen joints, smoking habits, other systemic diseases and medications. Serum thiol-disulfide homeostasis tests (TDHT), catalase (CAT), ceruloplasmin (Cp), arylesterase (ARES), paraoxonase (PON), stimulated paraoxonase (SPON), total antioxidant status (TAS), total oxidant status (TOS), malondialdehyde (MDA), myeloperoxidase (MPO), routine biochemistry tests and inflammatory markers%253A Interleukin-1b (IL-1b), interleukin-6 (IL-6), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were measured. Results%253A MPO, TDHT, MDA, MPO and inflammatory markers (IL-6, CRP and ESR) were significantly different in HOA patients from those in control group (p%253D0.005%253B p%253D0.001%253B p%253D0.014%253B p%253D0.005%253B p%253D0.012%253B p%253D0.003 and plt%253B0.001, respectively). Conclusion%253A Our results support that oxidative stress increases in HOA and with the severity of the disease, suggesting that oxidative stress might be involved in pathogenesis of HOA

Impedance testing of porous Si3N4 scaffolds for skeletal implant applications

Si3N4 ceramics show excellent characteristics of mechanical and chemical resistance in combination with good biocompatibility, antibacterial property and radiolucency. Therefore, they are intensively studied as structural materials in skeletal implant applications. Despite their attractive properties, there are limited data in the field about in vitro studies of cellular growth on ceramic implant materials. In this study, the growth of bone cells was investigated on porous Silicon Nitride (Si3N4) ceramic implant by using electrochemical impedance spectroscopy (EIS). Partial sintering was performed at 1700 °C with limited amount of sintering additive for the production of porous Si3N4 scaffolds. All samples were then sterilized by using ethylene oxide followed by culturing MG-63 osteosarcoma cells on the substrates for in vitro assays. At 20 and 36 hours, EIS was performed and results demonstrated that magnitude of the impedance as a result of the changes in the culture media increased after incubation with osteosarcoma cells. The changes are attributed to the cellular uptake of charged molecules from the media. Si3N4 samples appear to show large impedance magnitude changes, especially between 100 Hz and 1 Hz. Impedance changes were also correlated with WST-1 measurements (36 hr) and DAPI results