Flexural strength,biocompatibility, and antimicrobial activity of a polymethyl methacrylate denture resin enhanced with graphene and silver nanoparticles

Clinical Oral Investigations - The study evaluates the effect of adding graphene-Ag nanoparticles (G-AgNp) to a PMMA auto-polymerizing resin, with focus on antibacterial activity, cytotoxicity,...     

New Composite Hydrogel Based on Whey and Gelatin Crosslinked with Copper Sulphate

By-products from the meat and dairy industries are important sources of high biological value proteins. This paper explores possibilities for improving the swelling and integrity of a cross-linked whey and gelatin hydrogel with different amounts of CuSO₄ × 5H₂O. Overall, swelling tests demonstrate that cross-linked samples show a better hydration capacity and stability in the hydration medium, but different copper concentrations lead to different swelling behavior. At concentrations smaller than 0.39%, the sample lasts for 75 h in a water environment before beginning to disintegrate. At a concentration of copper sulphate higher than 0.55%, the stability of the sample increased substantially. The swelling kinetics has been investigated. The diffusion constant values increased with the increase in copper concentration, but, at the highest concentration of copper (0.86%), its value has decreased. Spectroscopy analyses such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-VIS), and nuclear magnetic resonance (NMR) relaxometry analyses revealed changes in the secondary and tertiary structure of proteins as a result of the interaction of Cu²⁺ ions with functional groups of protein chains. In addition to its cross-linking ability, CuSO₄ × 5H₂O has also shown excellent antibacterial properties over common bacterial strains responsible for food spoilage. The result of this research demonstrates the potential of this hydrogel system as a unique material for food packaging.     

Course of functional status and pain in osteoarthritis of the hip or knee: a systematic review of the literature

OBJECTIVE: To systematically review studies describing the course of functioning in patients with osteoarthritis (OA) of the hip or knee and identifying potential prognostic factors. METHODS: A systematic search was performed. Studies involving patients with hip or knee OA, >6 months of followup, and outcome measures on functional status or pain were included. Methodologic quality was assessed using a standardized set of 11 criteria; a qualitative data analysis was performed. RESULTS: Approximately 6,500 titles and abstracts were screened and 48 publications were considered for inclusion. Eighteen studies, 4 of which met the high methodologic quality criteria, were included. For hip OA, there was limited evidence that functional status and pain do not change during the first 3 years of followup. After 3 years, however, a worsening of functional status and pain was seen. For knee OA, there was conflicting evidence for the first 3 years and limited evidence for worsening of pain and functional status after 3 years. Furthermore, limited evidence was established for negative associations between future functional status and laxity, proprioceptive inaccuracy, age, body mass index, and knee pain intensity. In contrast, greater muscle strength, better mental health, better self-efficacy, social support, and more aerobic exercise were protective factors in the first 3 years. CONCLUSION: Pain and functional status in hip or knee OA seem to deteriorate slowly, with limited evidence for worsening after 3 years of followup. In specific subgroups, prognosis in the first 3 years of followup was either worse or better, as both risk factors and protective factors were identified. Prognostic factors included biomechanical factors, psychological factors, clinical factors, and treatment modalities. To strengthen the evidence, further high-quality longitudinal research on hip or knee OA functioning is needed.