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A large multinuclear cell associated with bone resorption.
A large surgical apparatus through which leverage can be exerted to effect osteoclasis.



a cell that is involved in the destruction and resorption of bone tissue in vertebrate animals and man. An osteoclast contains from three to several dozen nuclei and a great many lysosomes, whose hydrolytic enzymes upon release from the osteoclasts resorb the mineral matrix of bone and calcified cartilage.

References in periodicals archive ?
For differentiation of BMNCs into osteoclasts, BMNCs were cultured for 7 days in medium containing macrophage colony-stimulating factor (M-CSF; 10 ng/ml), RANKL (50 ng/ml) (Reprotech; Rocky Hill, NJ, USA), and LPNS (0, 50, 100 or 200 mg/l).
The key signalling protein for osteoclast differentiation is RANKL, which attaches to a receptor that is widely expressed on osteoclasts--RANK.
In addition, the proteins needed for the differentiation of the macrophages into osteoclasts will be incorporated in these NPs.
Osteoblasts not only play a central role in bone formation by synthesizing several bone matrix proteins, but regulate osteoclast maturation through expression of soluble factors RANKL and M-CSF, resulting in bone resorption.
All peptides appeared to have an impact on osteoclasts mediating bone resorption.
They discovered that human smokers produce unusually large amounts of two proteins that foster production of bone-resorbing osteoclasts compared to non-smokers.
Osteblasts and osteoclasts are not the only cellular elements contributing to the bone turnover process.
Bone resorption by osteoclasts involves the breakdown of both the mineral and organic bone matrix of bone, the latter mainly involving type I collagen.
The bisphosphonates, which are non-metabolized synthetic analogs of pyrophosphate synthetase, function through their inhibition of osseous resorption via suppression of osteoclast activity.
OPG binds to RANKL and neutralizes it, blocking the differentiation and activation of new osteoclasts and shortening the survival time of existing osteoclasts.
In the in vitro study, a mixed culture of osteoblasts and osteoclasts was used to represent the composition of a normal bone and levels of alkaline phosphatase (ALP), a marker of osteoblast activity, were measured.