This study investigates the in vitro biocompatibility, corrosion resistance, and adhesion strength of a gas abrasive-treated Ti6Al4V alloy, alongside microplasma-sprayed titanium and tantalum coatings. Employing a novel approach in selecting microplasma spray parameters, this study successfully engineers coatings with tailored porosity, roughness, and over 20% porosity with pore sizes up to 200 μm, aiming to enhance bone in-growth and implant integration. This study introduces an innovative methodology for quantifying surface roughness using laser electron microscopy and scanning electron microscopy, facilitating detailed morphological analysis of both the substrate and coatings. Extensive evaluations, including tests for in vitro biocompatibility, corrosion resistance, and adhesive strength, revealed that all three materials are biocompatible, with tantalum coatings exhibiting superior cell proliferation and osteogenic differentiation, as well as the highest corrosion resistance. Titanium coatings followed closely, demonstrating favorable osteogenic properties and enhanced roughness, which is crucial for cell behavior and attachment. These coatings also displayed superior tensile adhesive strengths (27.6 ± 0.9 MPa for Ti and 28.0 ± 4.9 MPa for Ta), surpassing the ISO 13179-1 standard and indicating a robust bond with the substrate. Our findings offer significant advancements in biomaterials for medical implants, introducing microplasma spraying as a versatile tool for customizing implant coatings, particularly emphasizing the superior performance of tantalum coatings in terms of biocompatibility, osteogenic potential, and corrosion resistance. This suggests that tantalum coatings are a promising alternative for enhancing the performance of metal implants, especially in applications demanding high biocompatibility and corrosion resistance.

Background: Pathological bone fracturing is an escalating problem driven by increasing aging and obesity. Bioceramics, particularly tricalcium-phosphate-based materials (TCP), are renowned for their exceptional biocompatibility, osteoconductivity, and ability to promote biomineralization. In the present study, we designed and characterized TCP porous granules doped with strontium (Sr) and copper (Cu) (CuSr TCP). Sr²⁺ ions were selected as Sr plays a crucial role in early bone formation, osteogenesis, and angiogenesis; Cu²⁺ ions possess antibacterial properties. Materials: The synthesized CuSr TCP granules were characterized by X-ray diffraction. Cytotoxicity and cell proliferation analyses’ assays were performed through the lactate dehydrogenase (LDH) activity and CCK-8 viability tests in rat bone marrow-derived mesenchymal stem cells (BM-MSCs). Hemolytic activity was carried out with human red blood cells (RBCs). Early and late osteogenesis were assessed with alkaline phosphatase (ALP) and Alizarin Red S activity in human osteoblast progenitor cells and rat BM-MSCs. The influence of CuSr TCP on angiogenesis was investigated in human umbilical vein endothelial cells (HUVECs). Results: We have demonstrated that media enriched with CuSr TCP in concentrations ranging from 0.1 mg/mL to 1 mg/mL were not cytotoxic and did not significantly affect cell proliferation rate motility. Moreover, a concentration of 0.5 mg/mL showed a 2.5-fold increase in the migration potential of BM-MSCs. We also found that CuSr TCP-enriched media slightly increased early osteogenesis. We also found that Sr and Cu substitutions in TCP particles significantly enhanced the measured angiogenic parameters compared to control and unsubstituted TCP granules. Conclusion: Our results demonstrate that TCP porous granules doped with Sr and Cu are biocompatible, promote osteodifferentiation and angiogenesis, and could be recommended for further in vivo studies.

Background/Objectives: Periprosthetic infection remains a major challenge in orthopedic implantation, particularly for porous titanium implants that promote bone integration but may also facilitate bacterial colonization. This study evaluated magnetron-sputtered tantalum–copper (TaCu) and niobium–copper (NbCu) coatings on Ti6Al4V implants following Staphylococcus aureus challenge, with particular attention to implant geometry. Methods: TaCu-coated, NbCu-coated, and uncoated Ti6Al4V implants with dense (smooth) or porous (rough) geometries were evaluated. Cytocompatibility was assessed using rat mesenchymal stromal cells exposed to implant-conditioned media, and Cu release was measured by ICP-MS. Twenty-four rabbits received femoral implants followed by local S. aureus inoculation. Outcomes were assessed by clinical observation, macroscopic examination, radiography, and confocal microscopy. DAPI-positive structures were analyzed three-dimensionally using a 100 μm³ volume threshold and sensitivity analysis. Results: Neither TaCu- nor NbCu-conditioned media adversely affected MSC metabolic activity, and both coatings released measurable Cu. Despite infection across groups, TaCu-coated implants showed the greatest preservation of implant retention. Analysis of 6,248 segmented objects from 21 animals showed significant associations of coating and implant geometry with the proportion of small DAPI-positive objects (both p < 0.001). Uncoated Ti6Al4V showed higher proportions than NbCu and TaCu (Holm-adjusted p < 0.001), whereas TaCu and NbCu did not differ (p = 0.731). Rough implants showed higher proportions than smooth implants, and the coating-related pattern persisted across thresholds of 25–200 μm³. An additional analysis using a 5 µm³ threshold confirmed differences in the relative proportions of very small DAPI-positive objects (p = 0.0156), whereas total volumetric object density did not differ significantly among coating groups (p = 0.769). Conclusions: Cu-containing coatings altered the distribution of implant-associated DAPI-positive structures without adversely affecting MSC metabolic activity. TaCu showed the greatest preservation of implant retention despite a confocal profile comparable to NbCu, supporting further investigation of TaCu for infection-resistant orthopedic implants.

Background. Aging represents a complex biological process characterized by the progressive accumulation of molecular and cellular alterations that ultimately lead to a decline in tissue functional capacity and the development of age-associated diseases. The concept of the hallmarks of aging provides a systematic framework for analyzing the mechanisms underlying biological aging. In recent years, accumulating evidence has highlighted the important role of the small GTPase Cdc42 in the regulation of aging-related processes at multiple levels of cellular organization. This review presents an analysis of current studies addressing the impact of Cdc42 on all three categories of aging hallmarks—primary, antagonistic, and integrative. The mechanisms through which Cdc42 contributes to genomic instability, epigenetic alterations, cellular senescence, oxidative stress, and impaired intercellular communication, including SASP-dependent processes, are discussed. Particular attention is given to the role of Cdc42 in the regulation of cytoskeletal dynamics, mitochondrial function, and the DNA damage response. The potential of pharmacological inhibition of Cdc42 is also considered as a promising approach for correcting age-associated cellular dysfunctions and developing geroprotective strategies. This review underscores the central role of Cdc42 in the biology of aging and provides a foundation for future studies aimed at slowing age-related physiological processes and promoting functional longevity. Keywords: Cdc42, aging, cellular senescence, hallmarks of aging, mesenchymal stem cells, genomic instability, oxidative stress, SASP, epigenetic alterations, geroprotection.

Background: Pathological bone fracturing is an escalating problem driven by increasing aging and obesity. Bioceramics, particularly tricalcium-phosphate-based materials (TCP), are renowned for their exceptional biocompatibility, osteoconductivity, and ability to promote biomineralization. In the present study, we designed and characterized TCP porous granules doped with Strontium (Sr) and Copper (Cu). Sr2+ ions were selected as it plays a crucial role in early bone formation, osteogenesis and angiogenesis; Cu2+ ions possesses antibacterial properties. Materials: The synthesized CuSr TCP granules were characterized by X-Ray Diffraction. Cytotoxicity and cell proliferation analyses assays were performed through the Lactate dehydrogenase (LDH) activity and CCK-8 viability tests in rat bone marrow-derived mesenchymal stem cells (BM-MSCs). Hemolytic activity was carried out with human red blood cells (RBCs). Early and late osteogenesis was assessed with alkaline phosphatase (ALP) and Alizarin Red S activity in human osteoblast progenitor cells and rat BM-MSCs. The influence of Sr and Cu-substituted TCP on angiogenesis was investigated in human umbilical vein endothelial cells (HUVECs). Results: We have demonstrated that a media enriched with CuSr TCP in concentrations ranging from 0.1 mg/ml to 1 mg/ml was not cytotoxic and did not significantly affect cell proliferation rate motility. Moreover, a concentration of 0.5 mg/ml has shown a 2.5-fold increase in the migration potential of BM-MSCs. We also found that CuSr TCP-enriched media slightly increased early osteogenesis. We also found that Sr and Cu substitutions in TCP particles significantly enhanced the measured angiogenic parameters compared to control and unsubstituted TCP granules. Conclusion: Our results demonstrate that TCP porous granules doped with Sr and Cu are biocompatible, promote osteodifferentiation and angiogenesis, and could be recommended for further in vivo studies.