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The wear behaviors of combinations comprised of a new titanium alloy, Ti29Nb13Ta4.6Zr (TNTZ) and a conventional titanium alloy, Ti6Al4V extra-low interstitial (Ti64) were investigated using ball-on-disc type configuration in Ringer's solution for metal-to-metal contacting biomedical implant applications. The worn surfaces, wear debris, and subsurface damage were analyzed using a scanning electron microscopy combined with energy-dispersive spectroscopy and an electron probe microanalysis. Moreover theses wear characteristics are compared to the results obtained from the wear tests in air. Volume loss of both the disc and ball primarily increases for the TNTZ disc/TNTZ ball combination in Ringer's solution compared to that in air. This increase can be explained by the ejection of debris from the contact region induced by the presence of Ringer's solution. Subsequently, this increases the number of areas with asperity junctions between the disc and ball, thereby leading to severe delamination wear. In contrast, the volume loss of both the disc and ball decrease for the Ti64 disc/Ti64 ball combination in Ringer's solution compared to that in air. It is believed that the predominately abrasive wear associated with Ti64 is effectively suppressed by the use of Ringer's solution.

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Hepatitis B virus (HBV) is a main cause of chronic liver disease worldwide and can lead to severe liver diseases. The World Health Organization has planned to eliminate viral hepatitis, including hepatitis caused by HBV and hepatitis C virus, by 2030. As mother-to-child transmission (MTCT) of HBV is a main cause of chronic HBV infection, MTCT prevention is the main target to reduce the risk of chronic HBV infection and eliminate the disease. Recent clinical trials and meta-analyses found that antiviral therapy could prevent MTCT effectively in mothers with ≥200,000 IU/mL of HBV DNA, in combination with serial vaccination and hepatitis B immune globulin administration in infants. Despite the preventive role of antivirals for MTCT of HBV, there are several concerns regarding antiviral therapy with respect to the safety of the mother and fetus during pregnancy. This review summarizes the benefits and risks of antiviral treatment during pregnancy in women with chronic HBV infection.

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