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Item The effect of a high calcium dairy based supplement on parameters of bone health in pre-pubertal New Zealand children : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Nutritional Science at Massey University(Massey University, 2002) Merrilees, Megan JoanWith an ageing population and an increased awareness of the rising health costs of fractures caused by osteoporosis (1); the focus of osteoporosis research is changing from treatment to prevention. More recent studies have looked at the effect of calcium supplementation during childhood and adolescence as a method of increasing the peak bone mass (2-10). It is postulated this will lead to a decrease in fractures in later life. This study investigated the effect of a calcium enriched milk drink on bone density, bone mineral content and bone size in both male and female 8-10 year old New Zealand (NZ) pre-pubertal children. One hundred and fifty four NZ pre-pubertal boys and girls were randomized to receive a high calcium dairy (Ca 2+ =1200mg) drink or a control (Ca 2+ =400mg) drink for 18 months. They were assessed at baseline and then every 6 months for the first 18 months, during the supplementation period; they were then followed up 12 months later. Bone mineral density, and bone mineral content was assessed at the total body, hip and spine. Indicators of bone size were measured at the spine. Anthropometric data was collected and Tanner stages of pubertal development, dietary calcium intake, compliance and medical questionnaires were administered. The calcium food frequency questionnaire was validated against a 3 day weighed food record at baseline. There was no significant difference between the 2 groups for bone mineral density or bone mineral content observed either before or after the intervention. Trends were seen in bone mineral density in the total hip (p=0.081) and the trochanter (p=0.088). There was no difference in vertebral height or width at any stage of the study, indicating no additional influence on bone size. There were no significant differences between height, weight, lean mass or fat mass. Both groups had high habitual calcium intakes at baseline and this continued throughout the study, resulting in calcium intakes above the estimated calcium threshold for both groups. In this 2 1/2 year study (18 months supplementation, 1 year follow-up) there was no difference in bone mineral density in children aged 8-12 years. This is most likely due to a high habitual dietary calcium intake, that even with minimal addition of calcium to the diet a threshold level was reached where no further benefit was seen.Item Bone mineral density characteristics of the third metacarpal /metatarsal distal epiphysis of thoroughbred horses : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University, Manawatu, New Zealand(Massey University, 2012) Bogers, Sophie HelenThis thesis includes two studies using non-invasive imaging techniques to quantify, in detail, the bone mineral density (BMD) characteristics of the distal third metacarpal (Mc3) and metatarsal (Mt3) epiphyses of Thoroughbred horses associated with exercise exposure and condylar fracture. Additionally, the relationship between the bone structure of the distal Mc3/Mt3 epiphysis and incurred cyclic loading, as well as techniques for imaging the area non-invasively, are reviewed. Mt3 bones from fourteen trained or untrained Thoroughbred horses and Mc3 bones from fourteen Thoroughbred racehorses with or without condylar fracture were scanned using peripheral quantitative computed tomography (pQCT) at a site on the distal epiphysis. The relative proportions of volumetric bone mineral density (BMDV) and the spatial distribution of BMDV were quantitatively assessed using conventional and ArcGIS software. The relative proportion of voxels within nine threshold categories of BMDV and spatial statistics of BMDV distribution were compared for regions of interest in the palmar/plantar epiphysis between respective treatment groups; trained vs. untrained controls or fractured vs. non-fractured controls. In study one, trained horses had a significantly higher (P=0.006) proportion of high BMDV voxels and a significantly lower (P=0.006) relative proportion of low BMDV voxels than controls in the central condylar regions of the plantar Mt3 epiphysis. In other regions of the plantar epiphysis the trained horses also had a significantly higher (P=0.006) relative proportion of high BMDV voxels than controls; however, there were no significant differences for the relative proportion of low BMDV voxels. These relationships were also evident with multiple correspondence analysis. There was strong to marked clustering of high BMDV voxels in the central condylar region of all of the trained horses (I = 0.64 - 1.0, P = 0.01) and no clustering of low BMDV voxels. In contrast, half of the control horses had clustering of high BMDV voxels, which was weak to strong (I = 0.64 - 1.0, P = 0.01) and there was weak to moderate clustering of low BMDV voxels in the lateral and medial central condylar regions (I = 0.45-0.62, P = 0.01 and I = 0.45-0.57, P = 0.01, respectively). In study two, there were no significant differences between the median age (P = 0.7), number of race starts (P = 0.5), the relative proportion of BMDV voxels, or the spatial distribution of BMDV voxels in regions of the palmar Mc3 epiphysis between the fractured and control groups. The results of this thesis suggest that the response of bone to exercise is specific in relation to anatomical site, the thresholds of BMD that change, and the spatial distribution of BMD. In both studies the exercise exposure was responsible for much of the variation in the relative proportions and the spatial distributions of BMDV. The clinical relevance of these findings are that detailed quantification of previous exercise exposure needs to be considered when determining if a BMD response of the Mt3/Mc3 epiphysis is part of a physiological or pathological finding.Item Inflammatory markers and bone health in postmenopausal women: a cross-sectional overview(BioMed Central Ltd, 10/07/2019) Ilesanmi-Oyelere BL; Schollum L; Kuhn-Sherlock B; McConnell M; Mros S; Coad J; Roy NC; Kruger MCBackground: Cytokines, chemokines, C-reactive proteins (CRP) and ferritin are known inflammatory markers. However, cytokines such as interleukin (IL-1β), (IL-6) and tumour necrosis factor (TNF-α) have been reported to interfere with both the bone resorption and bone formation processes. Similarly, immune cell cytokines are known to contribute to inflammation of the adipose tissue especially with obesity. IL-10 but not IL-33 has been linked to lower ferritin levels and anemia. In this study, we hypothesized that specific cytokine levels in the plasma of women with low bone mineral density (BMD) would be higher than those in the plasma of healthy women due to the actions of elevated levels of pro-inflammatory cytokines in inducing osteoclast formation and differentiation during senescence. Results: Levels of cytokines (IFNα2, IFN-γ, IL-12p70, IL-33) and monocyte chemoattractant protein-1 (MCP-1) were significantly higher in the plasma of the osteoporotic group compared to the osteopenic and/or healthy groups. Meanwhile CRP levels were significantly lower in women with osteoporosis (P = 0.040) than the osteopenic and healthy groups. Hip BMD values were significantly lower in women with high/detectable values of IL-1β (P = 0.020) and IL-6 (P = 0.030) compared to women where these were not detected. Similarly, women with high/detectable values of IL-1β had significantly lower spine BMD than those where IL-1β was not detected (P = 0.030). Participants' CRP levels were significantly positively correlated with BMI, fat mass and fat percentage (P < 0.001). In addition, ferritin levels of women with high/detectable values of anti-osteoclastogenic IL-10 (P = 0.012) and IL-33 (P = 0.017) were significantly lower than those where these were not detected. There was no statistically significant association between TNF-α and BMD of the hip and lumbar spine. Conclusions: High levels of cytokines (IFNα2, IFN-γ, IL-12p70, IL-33) and MCP-1 in apparently healthy postmenopausal women are associated with bone health issues. In addition, an increase in levels of IL-10 and IL-33 may be associated with low ferritin levels in this age group. Trial registration: ANZCTR, ACTRN12617000802303. Registered May 31st, 2017, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373020.Item The importance of fall history in fracture risk assessment(2013) Edwards MH; Jameson KA; Denison H; Harvey NC; Sayer AA; Dennison EM; Cooper C
