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Quercus species are utilized for their durable wood, providing sustenance for wildlife, conserving biodiversity, and contributing ecological, medicinal, and esthetic benefits to ecosystems and landscapes. In this study, we aimed to use the bark of three Quercus species ( Q. dalechampi , Q. fraineto , and Q. petraea ) for the synthesis of silver and gold nanoparticles (AgNPs and AuNPs). The aqueous extracts from the bark of Quercus sp. acted both as reducing and stabilizing agent, facilitating the rapid synthesis of AuNPs (AuQD, AuQF, and AuQP) and AgNPs (AgQD, AgQF, and AgQP). The obtained nanoparticles were characterized using UV-vis spectroscopy, TEM, DLS, and FTIR. Characterizations revealed that the nanoparticles exhibited a variety of shapes, such as polygonal, triangular, and spherical forms, with sizes ranging between 14 and 24 nm for AuNPs and 45-70 nm for AgNPs. The total phenolic content was assessed through spectroscopic methods, while several individual phenolic compounds were identified and quantified using UPLC-PDA. Furthermore, we assessed the antioxidant, antibacterial, and antifungal capacities of AuNPs, AgNPs, and raw extracts. The highest antioxidant activity was observed for raw extracts, followed by AgNPs and AuNPs, while the most potent antibacterial and antifungal activity was observed in AgQP. Moreover, cytotoxicity was examined in a human keratinocyte cell line (HaCaT). The results indicated no cytotoxic effects for AuNPs, while AgNPs and the raw extracts exhibited cytotoxic effects after 48 h of incubation. This research underscores the multifaceted utility of Quercus bark extracts in the green synthesis of metallic nanoparticles and their subsequent bioactivity assessment, suggesting promising perspectives for their application in various fields while urging cautious consideration of their cytotoxic implications.

Nanoporous/nanotubular complex oxide layers were developed on high-fraction β phase quaternary Ti-Nb-Zr-Ta and Ti-Nb-Zr-Fe promising biomedical alloys with a low elasticity modulus. Surface modification was achieved by electrochemical anodization aimed at the synthesis of the morphology of the nanostructures, which exhibited inner diameters of 15-100 nm. SEM, EDS, XRD, and current evolution analyses were performed for the characterization of the oxide layers. By optimizing the process parameters of electrochemical anodization, complex oxide layers with pore/tube openings of 18-92 nm on Ti-10Nb-10Zr-5Ta, 19-89 nm on Ti-20Nb-20Zr-4Ta, and 17-72 nm on Ti-29.3Nb-13.6Zr-1.9Fe alloys were synthesized using 1 M H 3 PO 4 + 0.5 wt% HF aqueous electrolytes and 0.5 wt% NH 4 F + 2 wt% H 2 0 + ethylene glycol organic electrolytes.

Helicobacter pylori is a common pathogen causing gastric inflammation and malignancy. Fetuin-A is a multifunctional protein that is involved in the regulation of calcification, insulin resistance and inflammation. Reports on serum levels of fetuin-A in acute H. pylori infection are contradictory. We intended to see whether H. pylori post-infection status has a long-term effect on serum fetuin-A levels in a well-characterized series of systemic lupus erythematosus cases. In this cross-sectional study 117 patients with systemic lupus erythematosus were enrolled. Helicobacter infection status and serum fetuin-A concentration were determined by ELISA and radial immunodiffusion, respectively. H. pylori positive patients had higher serum fetuin-A concentration than negative ones: 517 (456-603) vs. 476 (408-544) mg L-1, median (25-75% percentiles), P = 0.020. No other parameters differed between these groups. During univariate regression analysis fetuin-A levels were associated with Erythrocyte sedimentation rate (ESR), White blood cell count (WBC), C-reactive protein (CRP), serum total protein, albumin, and the SLEDAI index at the time of diagnosis but only serum albumin remained a significant determinant in multivariate regression study.