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Introduction
Published in Stanton H. Cohn, Non-Invasive Measurements of Bone Mass and Their Clinical Application, 2020
The current interest in the determination of bone mass reflects the recognition of the physiological importance of bone, with its wide range of functions. Bone is a particularly interesting tissue to study. Unlike soft tissue, it imprints and then retains, for long periods, evidence of events experienced by the organism through changes in its morphology, and in its physical and chemical properties. The high mineral content of the bone makes it amenable to study by means of non-invasive radiological techniques which basically measure the bone density.
Safety factors, reserve and trade-offs
Published in Francesco E. Marino, Human Fatigue, 2019
One of the most pronounced changes that occur to bone is the increase in the percentage of mineralisation with advancing age. The outcome of this mineralisation is that energy absorption decreases by a factor of three between the ages of 3 and 90, as reported for the cortical bone of the femur (Currey 1979). Effectively, this results in decreased plastic deformation before a fracture occurs. On this basis, the consequence is that the safety factor of bone and more generally the skeleton declines with age because of the quality of the bone material (Biewener 1993). The unavoidable reduction in bone mineral density (osteopenia) and the subsequent development of bone mass loss and the associated microarchitecture (osteoporosis) lead to the increased risk of fracture. However, this is a complex phenomenon that is dependent on so many factors, including genetics, nutrition, gender and the volume of physical activity that one undertakes over the lifespan in addition to the lean and fat mass components (Taaffe et al. 2001). Although it may seem inevitable that the safety factor of the skeleton is reduced over the life span, it is also evident that the decrease in the safety factor can also be retarded given the appropriate conditions. It is well known that exercise, and in particular resistance exercise, can have a positive effect on bone health if the program can be maintained (Lang et al. 2010).
Osteoporosis
Published in Gill Wakley, Ruth Chambers, Paul Dieppe, Musculoskeletal Matters in Primary Care, 2018
Gill Wakley, Ruth Chambers, Paul Dieppe
Drug treatments for improving bone mass (or preventing further loss of bone mass) are summarised in the guidelines from the Royal College of Physicians,18 and you could consider the medications in Table 9.2 for established osteoporosis or for osteopenia with a history of previous fracture.48
Resveratrol promotes bone mass in ovariectomized rats and the SIRT1 rs7896005 SNP is associated with bone mass in women during perimenopause and early postmenopause
Published in Climacteric, 2023
X. Wang, C. Lu, Y. Chen, Q. Wang, X. Bao, Z. Zhang, X. Huang
The recommended evaluation for bone mass is measuring BMD using dual-energy X-ray absorptiometry, and the T-score is the recommended diagnostic criterion. Normal bone mass is defined as a T-score greater than or equal to −1.0 SD, and a T-score of −1.0 to –2.5 SD is considered as osteopenia and low bone mass. Individuals with T-score of −2.5 SD or less have osteoporosis and are more likely to fracture [32]. In women, bone mass peaks at 25–30 years of age and is rapidly lost during menopause, including perimenopause and early postmenopause, but is slightly reduced in late postmenopause [21]. Considering this rapid bone loss, it is essential to address it during this time-limited window to prevent rapid bone loss and microarchitectural damage. We recruited 38 women with normal bone mass and 38 women with low bone mass in perimenopause and early postmenopause, according to STRAW + 10 [24]. We found that serum SIRT1 protein levels were significantly decreased in osteopenia, but the BMI also differed significantly between the two groups, which is considered to be a factor related to bone mass and fracture [33]. However, even after adjustment for BMI, age and other factors, a significant association between SIRT1 and BMD remained.
Body composition and 6 minute walking ability in late-onset pompe disease patients after 9 years of enzyme replacement therapy
Published in International Journal of Neuroscience, 2022
Gerasimos Terzis, Georgios Papadimas, Argyro Krase, Eleni Kontou, Ioannis Arnaoutis, Constantinos Papadopoulos
Data were retrieved from the regular examination files of three male and three female late-onset Pompe disease patients of our center. Adult, ambulatory patients receiving regular intravenous ERT infusions were included in this study. Patients with diseases that could potentially affect bone mineral density (e.g. primary hyperparathyroidism, rheumatologic disorders) and patients using medications known to affect bone mass (e.g. corticosteroids, biphosphonates) were excluded. Initial diagnosis of Pompe disease was confirmed in all cases by deficient GAA activity in cultured fibroblasts and mutational analysis of genomic DNA isolated from peripheral blood leukocytes. All subjects received ERT with alpha-glucosidase (Myozyme, Genzyme, USA) every fourteen days with 20 mg/kg, continually for 9 years. No serious adverse reactions were observed due to the ERT throughout the 9 year period. The initial characteristics of the patients, including the corresponding enzyme deficiency and gene point mutations, are presented in Table 1. None of the patients required ventilation support at study entry. The experimental protocol was previously approved by the Ethics Committee of the Eginition Hospital, of the Medical School of the National and Kapodistrian University of Athens, Greece. All patients gave their written informed consent for inclusion in this study.
It starts from the womb: maximizing bone health
Published in Climacteric, 2022
R. F. Vasanwala, L. Gani, S. B. Ang
Both animal and human studies indicate that low protein intake is detrimental for both the acquisition of bone mass during growth and its conservation during adulthood. Low protein intake impairs both the production and action of IGF-1 [16,17]. Most data seem to confirm that an adequate intake of calcium is important to reach skeletal maturity in adolescence. Prospective randomized clinical trials have shown that calcium supplementation may increase the acquisition of bone mass during adolescence, early adulthood and until the third decade of life. When that calcium supplementation ceases, the beneficial effect on bone seems to disappear. Bone growth and development are related to the amount of calcium consumed, and calcium intake recommended to meet these needs in children and adolescents has been established by various authorities. An inadequate intake of calcium may contribute to failure to develop bone from the first months of life. Calcium intake in some studies appeared insufficient in subgroups of children and adolescents, especially in girls. Data suggest that the recommended dietary levels of calcium in order to allow a female teenager to achieve full genetic potential of bone mass is estimated to be around 1200–1500 mg/day [48–51].