RESUMEN
Osteoporosis is a common disease of old age that affects millions of people worldwide. Besides, it has been a chronic disease difficult to treat in the elderly, so it is of great significance to develop new drugs for the treatment of senile osteoporosis. The endocannabinoid system contains cannabinoid ligands, endocannabinoid receptors, and enzymes required for the synthesis and degradation of endocannabinoids, which play an important role in bone metabolism. Preclinical studies using endocannabinoid system-based therapies in animal models and in vitro have shown that endocannabinoid systems can prevent senile osteoporosis and highlight their therapeutic potential for senile osteoporosis. In this paper, PubMed, ScienceDirect, CNKY, and Wanfang databases were searched for articles related to the endocannabinoid system and osteoporosis. This paper analyzed the pathogenesis of senile osteoporosis (such as calcium, active vitamin D3 deficiency or insufficiency, sex hormone deficiency, cell function decline and secondary to chronic diseases, etc.), and reviewed the various components of the endocannabinoid system and their application in osteoporosis by regulating bone homeostasis in recent years, providing a new direction for the clinical treatment of senile osteoporosis.
RESUMEN
Polyetherketoneketone (PEKK) is a semi-crystalline linear thermoplastic polymer with two ketone bonds and one ether bond in the main chain structure. It has many advantages such as elastic modulus close to that of natural human bone, biocompatibility, good chemical stability, radiolucency, compatibility with MRI, etc, which make it a new biomaterial for the production of orthopedic implants. The development of PEKK composites with better bone bioactivity without compromising the original properties of PEKK through special material preparation processes has become a hotspot. PEKK composites are made by combining biological ceramics (hydroxyapatite, silicon nitride) and metals with good biocompatibility (aluminum, tantalum and titanium). These composites not only retain the elastic modulus similar to that of human bone, but also improve hardness, biocompatibility, antibacterial properties, and bone integration ability, and thus have great potential in the field of orthopedic implants. The application of PEKK and its composites in the orthopedic field was searched in PubMed, Embase, ScienceDirect, CNKI and Wanfang databases. The properties advantages and disadvantages of PEKK and its composite materials modified by various methods in the recnt years (e.g. modification doping mixture, modification of the surface by sulfonation, 3D printing and treatment by surface deposition) were analyzed to provide a reference for the preparation clinically usable orthopedic implants with different functions.