Currently ‘accepted’ treatments for bone disease utilise drugs that inhibit osteoclastic bone resorption; these lead to a reduction in subsequent bone loss and thence, indirectly, to an increase in bone mass and fewer fractures. Three classes of compounds currently form the mainstay of therapy for osteoporosis: oestrogens (hormone-replacement therapy), ‘selective oestrogen receptor modulators’ and the bisphosphonates. Problems of patient compliance, real or theoretical long-term toxicological risks and the lack of bone anabolic agents of clinical utility suggest that there is a need for the development of further novel osteoclast resorption inhibitors. Recent biological and genetic findings in the area of bone cell function have led to the identification of new drug targets. These drugs include agents that (directly or indirectly): inhibit osteoclast adhesion to bone matrix; modify osteoclast differentiation; act on the proton pump and hence affect extracellullar acidification; antagonise extracellular enzymes that are involved in bone matrix protein degradation. Particular emphasis is placed in the present review on the evaluation of antagonists of αvβ3 integrin-mediated cell adhesion for use in bone disease. The wealth of new agents being developed suggests that resorption inhibition will be the best treatment for osteoporosis in the short to medium term, with the long-term aim still being toward developing anabolic drugs or cell therapeutics.

Population ageing affects the entire world population. Also at world level one can observe a sharp increase in the proportion of older people. The challenge posed by population ageing translates into ensuring that the extra years of life will be as good as possible, free from high-cost dependency. Omega-3 fatty acids are now generally recognized as potential key nutrients to prevent the pathological conditions associated to the aging process. Ageing physiological process, its association with quality of life and the impact of omega-3 fatty acids intake and/or status is the focus of the present review. This report deals with the effects of omega-3 fatty acids on normal aging of older adults ( ≥  65 years) mainly on the effects such as nutritional status itself, cognition, bone health, muscle tonus, and general health status. The preliminary broad search of the literature on the effects of omega-3 fatty acids on normal aging yielded 685 citations. Forty two full text papers were checked for inclusion and thirty six studies were finally included in this review. It may be concluded that paradoxically even though the elderly population is the largest one, the number of studies and the methodology employed clearly lacks of sufficient evidence to establish definite conclusions on the effects of omega-3 fatty acids on aging metabolism without pathological conditions and on quality of life.

Laying hens have a unique bone turnover due to the daily egg laying cycle. Laying hens have three distinctive kinds of bones related to egg formation: cortical, cancellous, and medullary bones. Cortical bone is a compact structural bone, whereas cancellous bone is the three-dimensional lattice-like honeycomb architecture at the end of long bones. Medullary bone is a highly labile woven bone lying in the marrow cavities. Medullary bone acts as Ca storage for egg shell formation. Thus, bone quality is closely related with egg production and eggshell quality. During the daily egg laying cycle, medullary bone osteoclasts alternately cease and accelerate bone resorption. Although osteoclast numbers are not changed during the daily egg laying cycle, considerable morphological changes in osteoclasts occur along with changes in calcium requirements for egg shell formation. Furthermore, the selection of proper methods is critical to obtain precise bone evaluation data, and include bone ashing, densitometric techniques, mechanical testing, or histomorphometry to evaluate bone status in laying hens. Since bone metabolism in laying hens is related to economic and animal welfare issues, better understanding of bone metabolism in laying hens would be important to enhance productivity and improve animal welfare.

Atomic force microscopy (AFM) is a specialised form of scanning probe microscopy, which was invented by Binnig and colleagues in 1986. Since then, AFM has been increasingly used to study biomedical problems. Because of its high resolution, AFM has been used to examine the topography or shape of surfaces, such as during the molecular imaging of proteins. This, combined with the ability to operate under known force regimes, makes AFM technology particularly useful for measuring intermolecular bond forces and assessing the mechanical properties of biological materials. Many of the constraints (e.g. complex instrumentation, slow acquisition speeds and poor vertical range) that previously limited the use of AFM in cell biology are now beginning to be resolved. Technological advances will enable AFM to challenge both confocal laser scanning microscopy and scanning electron microscopy as a method for carrying out three-dimensional imaging. Its use as both a precise micro-manipulator and a measurement tool will probably result in many novel and exciting applications in the future. In this article, we have reviewed some of the current biological applications of AFM, and illustrated these applications using studies of the cell biology of bone and integrin-mediated adhesion.

These guidelines review the relevant literature on the way plant phyto-oestrogens act on bone and the responsiveness of different bone cell systems to phyto-oestrogenic compounds. The primary emphasis is on the experimental conditions used, the markers available for assessing osteoblast and osteoclast function, and their expected sensitivity. Finally, we assess the published results to derive some general recommendations for in vitro experiments in this area of research.

For comparison with chemically fixed osteoclasts, we prepared chick osteoclasts by quick freezing followed by freeze-substitution. In spite of technical difficulties this demonstrated that osteoclasts can be satisfactorily frozen in situ by the metal contact method. Ultrastructural differences were revealed between conventional fixation and quick freezing. Compared with conventional fixation, the quick freezing method appeared to improve preservation: (1) a discrete trilaminar plasma membrane and other intracellular membranes showed a smooth profile without undulation or rupture; (2) cytoskeletal components appeared to be clearer, straighter, and more numerous; (3) the interior of the ruffled finger contained interconnected lattice structures whereas highly organised microfilaments were seen in the clear zone; (4) well developed tubulovesicular structures (TVSs) that branched or anastomosed with each other were revealed in the cytoplasm; (5) the contents of intracellular membrane systems including the nuclear envelope, endoplasmic reticulum, and Golgi complex were stained to a various extent; (6) vesicles and vacuoles were much smaller, round and well-defined with electron-dense contents; (7) crystalline structures were seen at the extracellular channels of the ruffled border, in the lumen of TVSs, and in vesicles; (8) in some instances mitochondrial granules were visible; (9) within the resorptive lacuna, osteoclasts adhered to the degraded bone matrix without any intervening empty space.