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This study explores the tribological properties of mollusk‐shell‐high‐density polyethylene (MS‐HDPE) biocomposites and diamond‐like carbon (DLC)‐coated metal beads as potential substitutes for hip joint prostheses. HDPE biocomposites with 0, 5, and 10 wt% of MS were developed using hot compression molding. Coatings included pure DLC, DLC‐Si, and DLC W:H. Wear tests on a ball‐on‐disk tribometer examined friction and wear rates against coated and uncoated balls, along with wear morphology. MS‐HDPE demonstrated superior tribological performance against DLC, achieving a 67% reduction in specific wear rate compared to pure HDPE. The study suggests that 5 wt% MS‐HDPE coupled with a DLC‐coated counterpart coating could be a promising combination for orthopedic applications, presenting a potential solution to metal corrosion and wear debris issues in orthopedic implants. Highlights: Tested coatings: DLC, DLC‐Si, and DLC W:H.Biocomposite wear versus coated balls.DLC coating improves wear with shell fillers.Mollusk shell strengthens biocomposites.Reduced wear rate by 63% and friction by 77%. [ABSTRACT FROM AUTHOR]

The effect of hygrothermal aging on the tribological and mechanical behaviors of UHMWPE biocomposites reinforced with different weight fractions of mollusc shell (MS) particles was investigated. The developed MS-UHMWPE biocomposites samples were subjected to accelerated hygrothermal aging in Ringer's solution at 80°C. The results showed that hygrothermal aging increases the tribological behavior of these biocomposites. The effect of hygrothermal aging on the wear resistance depends on the reinforcement rate of the MS particles. The mechanical properties of the MS-UHMWPE biocomposite were affected by hygrothermal aging as well as by the weight content of the added MS particles. The modulus of elasticity increased with increasing MS particle content for all tested materials. A scenario of the wear mechanism of aged biocomposites will be proposed. [ABSTRACT FROM AUTHOR]

This article highlights the importance of the addition of Mollusc shell (MS) particles, as bio-filler, on the tribological behavior of high-density polyethylene (HDPE) matrix. The elaborated biocomposites are intended to be used as an orthopedic replacement biomaterial. Different mass content of MS (0, 5, 10, 15 and 20 wt. %) have been added to the HDPE matrix. FTIR analysis, crystallinity rate and Rockwell hardness of different bio-composites were performed. A reciprocating pin-on-disc tribometer was used to fulfil dry wear tests. FTIR analysis showed that the presence of MS particles improved the crystallinity of the HDPE phase. Adding to that, it was found that MS improved the hardness, friction coefficient and wear resistance of the HDPE polymer. In fact, by adding 5 wt. % of MS to the HDPE, good tribological properties were achieved. Scanning Electron Microscopy (SEM) was performed to investigate the wear morphology of biocomposites under dry condition. SEM images showed that the morphology of the worn surfaces had been improved by the addition of MS to the polymer. Finally, a wear scenario was proposed. [ABSTRACT FROM AUTHOR]

Background: Recent randomized controlled trial (RCTs) comparing percutaneous closure with antithrombotic treatment in patients with patent foramen ovale (PFO) and cryptogenic stroke revealed inconsistent results. Indeed, there is still no consensus on the management of these patients, namely closure or medical therapy treatment. Methods: To take stock of the PFO management after cryptogenic stroke, we conducted a literature review that included 16 articles dealing with different therapeutic strategies and long-term outcomes of these results. Results: The reviewed studies showed great methodological diversity rendering an exhaustive and balanced comparison between studies difficult. Low recurrence rates under prevention regimens, crossovers, procedure- and device-related complications, as well as inappropriate patient selection might explain the inconsistency of trials. However, despite the methodological heterogeneity certain patterns could be detected. It appears that device closure as secondary prevention measure is an effective and safe procedure reducing the recurrence of neurological events in cryptogenic stroke patients <60 years with large PFOs. Standardization of procedures and larger trials are needed to arrive to definitive conclusions. Conclusion: In cryptogenic stroke patients <60 years with large PFOs, PFO closure seems to be safe and more effective compared to medical treatment alone. For all other patients group, for example, patients >60 years further trials are needed to clarify the role of PFO closure. [ABSTRACT FROM AUTHOR]