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Childhood obesity is growing in prevalence. Obesity and bone dysfunctions may be related disorders, and therefore our aim was to study the impact of the early overfeeding (EO) in off spring bone health since weaning up to adulthood. To induce EO during lactation, litter size was adjusted to 3 male rats per litter (SL). Litter containing 10 pups per mother was the control (NL). Bone tissue was evaluated by dual-energy X-ray absorptiometry, computed tomography, microcomputed tomography, biomechanical tests, and serum analyses. SL off spring presented higher body weight, fat mass, lean mass from 21 up to 180 days, hyperphagia, and higher visceral fat mass. Bone analysis showed that SL off spring presented higher total bone mineral density (BMD) only at 180 days, and higher total bone mineral content and higher bone area from 21 until 180 days. At 180 days, SL off spring presented higher femur BMD and fourth lumbar vertebra (LV4) BMD, higher femoral head radiodensity and LV4 vertebral body radiodensity, lower trabecular pattern factor and trabecular separation, however with higher trabecular number, higher maximal load, resilience, stiff ness and break load, and lower break deformation. SL group had, at 180 days, higher osteocalcin and lower C-terminal cross-linked telopeptide of type I collagen (CTX I). We have shown that the excess of fat mass contributed to an increased bone mass, and hypothesized that this increase could be mediated by the hypothyroidism and previous higher thyroid hormone action and hyperleptinemia at weaning. Furthermore, the increased biomechanical loading due to increased body weight probably help us to understand the protective effects obesity exerts upon bone health. [ABSTRACT FROM AUTHOR]

Abstract: Bone quality is an evaluation index often applied in order to interpret clinical observations made upon bone health, such as bone mineral density, micro and macro architecture, and mineral content. Conventional inspection techniques do not provide full information on trabecular bone quality. This study shows the high resolution potential and the non-destructive character of X-ray microtomography and microfluorescence upon the application of such techniques for evaluating bone quality. The mineral content assessment was performed by two-dimensional concentration mappings of calcium, zinc, and strontium. The results showed significant changes in bone morphology. [Copyright &y& Elsevier]

Abstract: The X-ray microtomography is a non-destructive image technique that allows evaluation of inner structure of several kinds of materials, such as trabecular bone. The microarchitecture of osteoporosis bone becomes more fragile and susceptible to fractures. Strontium ranelate (Protos®) is a current oral medication used in the treatment of osteoporosis diseases, which promises to act stimulating the proliferation of osteoblasts, as well as inhibiting the proliferation of osteoclasts. In the present work, two ways to administer strontium ranelate are studied in experiments with rats and mice: via oral and via intra-peritoneal injections. Intra-peritoneal injections are easier and not susceptible to gastrointestinal tract issues such as diarrhoea and absorption variations. However, the only method to administrate the strontium ranelate described in literature is still the gavage. In order to establish the best technique for future experiments, structural bone changes in rats were evaluated. The results show that bone porosity parameter at the femoral head decreased after 23 days of treatment when both oral and intraperitoneal routes of strontium ranelate administration were applied, suggesting an improved bone microarchitecture. [Copyright &y& Elsevier]

Tibolone is a synthetic steroid with estrogenic, androgenic, and progestagenic properties used for the prevention of postmenopausal osteoporosis and treatment of climacteric symptoms. Tibolone shows almost no action on breast and endometrium, which are target-organs for estrogens and progesterone activity. The aim of this work was to investigate the spatial distribution of calcium and zinc minerals in the femoral head of ovariectomized rat in order to evaluate the effects of the long-term administration of tibolone. For that purpose X-ray microfluorescence was used with synchrotron radiation imaging technique which was performed at Brazilian Light Synchrotron Laboratory, Campinas, SP. Minerals were not homogeneously distributed in trabecular bone areas; a higher concentration of calcium in the trabecular regions at femoral heads was found in ovariectomized and tibolone-treated rats compared to ovariectomized and control groups. [ABSTRACT FROM AUTHOR]

Abstract: Characterization of trabeculae structures is one of the most important applications of imaging techniques in the biomedical area. The aim of this study was to investigate structure modifications in trabecular and cortical bones using non destructive techniques such as X-ray microtomography, X-ray microfluorescence by synchrotron radiation and scanning electron microscopy. The results obtained reveal the potential of this computational technique to verify the capability of characterization of internal bone structures. [Copyright &y& Elsevier]

Abstract: In recent years, the 3D X-ray microcomputed tomography (3DμCT) has become a useful method to access the internal geometry based microarchitecture of bones. All measurements are based on the image quality. In this context, the aim of this work is to investigate bone quality in terms of strength parameters determined by 3DμCT. The system that was used to do the 3DμCT was a microfocus Fein Focus which has a microfocus X-ray tube, adjustment of the magnification factor of the captured image by mobile supports and an image intensifier with a diameter of 9in. The results show that microtomography by microfocus X-ray tube is a powerful technique that can be used to analyze bone microstructures. A quantification procedure conducted with a locally developed program, produced images with 20μm of resolution for different bone samples. [Copyright &y& Elsevier]

Abstract: The abnormal accumulation or deficiency of trace elements may theoretically impair the formation of bone and contribute to osteoporosis. In this context, the knowledge of major and trace elements is very important in order to clarify many issues regarding diseases of the bone, such as osteoporosis, that remain unresolved. Several kinds of imaging techniques can be useful to access morphology and the minerals present in osteoporotic bones. In this work, synchrotron radiation X-ray microfluorescence was used as an X-ray imaging technique to investigate bone structures. Therefore, this research aims to improve the knowledge about some aspects of bone quality. The measurements were carried out at the Brazilian Synchrotron Laboratory Light Laboratory, in Brazil. A white beam with an energy range of 4–23keV, a 45°/45° geometry and a capillary optics were used. It was demonstrated that bone quality can and must be evaluated not only by considering the architecture of bones but also by taking into account the concentration and the distribution of minerals. Our results showed that the elemental distributions in bone zones on a micron scale were very helpful to understand functions in those structures. [Copyright &y& Elsevier]

Abstract: In this work, two X-ray techniques used were 3D microcomputed tomography (micro-CT) and X-ray microfluorescence (micro-XRF) in order to investigate the internal structure of the bone samples. Those two techniques work together, e.g. as a complement to each other, to characterize bones structure and composition. Initially, the specimens were used to do the scan procedure in the microcomputer tomography system and the second step consists of doing the X-ray microfluorescence analysis. The results show that both techniques are powerful methods for analyzing, inspecting and characterizing bone samples: they are alternative procedures for examining bone structures and compositions and they are complementary. [Copyright &y& Elsevier]

Abstract: The study of trabecular structures is important for understanding the mechanism of alcohol related to bone changes. Alcohol consumption can compromise the body mineral composition, affecting the bone metabolism and compromising the skeleton. The effects of the ethanol treatment on the internal microarchitecture of bone samples through 3D microcomputed tomography are shown in this study. The data was acquired from a radiographic system with a micro focus X-ray conic beam and it was used the Feldkamp''s technique was used to carry out the 3D reconstructions. The measured microstructure parameters, which were based on stereological concepts, were bone volume fraction, relationship between bone surface and volume, trabecular number, separation and thickness. The results show that this technique is able to analyze these kinds of structures, especially rat bone, as these structures in rats (trabecular diameter) are thinner than in human bones. [Copyright &y& Elsevier]

Abstract: In recent years, bone quantification led to a deeper knowledge of the 3D microarchitecture. In this study the bone architecture of rats was investigated based on 2D/3D morphometric analysis using microcomputed tomography, aiming at determining the effect of the image acquisition pixel on the quality of some 2D/3D morphometric parameters, such as porosity and trabecular density. Six pairs of bone samples were used and the scans were carried out using high microcomputed tomography system, operating at three different pixel sizes of 33.3μm, 15.0μm and 9.5μm. The results showed 2D parameters values lower than those obtained in the 3D analysis, mainly for trabecular density, separation and thickness. [Copyright &y& Elsevier]