The regeneration of cartilage has made great progress in the past few decades, Previous techniques for constructing tissue-engineered cartilage scaffolds mainly include particulate-leaching, gas-foaming, freeze-drying, and phase-separation techniques. Cartilage is heterogeneous, and it is difficult for traditional scaffolds to simulate such anisotropy. Therefore, the functional regeneration of cartilage is challenging. With advancements in additive manufacturing, it has become possible to prepare functional bionic scaffolds for structures and components by the codeposition of biological materials, cells, and active biomolecules, thereby achieving functional cartilage regeneration. This article reviews the applications of three dimensional (3D) printing techniques in the regeneration of cartilage at different anatomical locations, including articular cartilage, meniscus, intervertebral disc, and auricle. In addition, methods for preparing biomimetic constructs with regional structural gradients and regional componential gradients are discussed, with multinozzle 3D bioprinting technology as a future research direction for the functional regeneration and repair of cartilage.

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Respiratory diseases are significant recurrent threats to global public health. Since the 1918 Spanish flu pandemic, seasonal influenza viruses continue to cause epidemics around the world each year. More recently, the COVID-19 global pandemic conducted a public health crisis with more than 6 million deaths and it also severely affected the global economy. Due to the phenomenon that people get infection from objects carrying viruses, it has aroused people's attention to home disinfection. As there is no ideal existing common domestic disinfectant, new and safer antiviral disinfectants are urgently needed. Lysozyme is a natural antibacterial agent widespread in nature and widely used in healthcare and food industry because of is recognized safety. Recently, it has been shown that thermally denatured lysozyme has the ability to kill murine norovirus and hepatitis A virus. In our study, we also demonstrated that heat-denatured lysozyme (HDLz) had an antiviral effect against H1N1 influenza A virus, and we optimized its antiviral activities by testing different heating denaturation conditions, to generalize this property, using pseudotype virus neutralization assay, we found that HDLz can also inhibit the entry of H5N1, H5N6, and H7N1 avian influenza viruses as well as SARS-CoV and SARS-CoV-2 particles in cell with IC50 at the ng/mL range. Finally, using western blot analysis, we provide evidence that HDLz polymerization correlates with antiviral effect, which may be a precious possible quality control test. Altogether, our data support HDLz as a powerful anti-respiratory virus disinfectant as a sole or additive of current disinfectants to reduce concentration of toxic component.