MR-based Characterization of Bone Marrow in Its Relevance to Skeletal Disease in Patients With Diabetes...
Diabetes MellitusType 22 moreFor a long time, no direct connection was seen between the two common diseases diabetes mellitus and osteoporosis. However, as more and more younger people are affected by obesity, develop type 2 diabetes mellitus and suffer osteoporotic fractures, the question of a connection between these clinical pictures has now arisen. Modern magnetic resonance imaging and spectroscopy techniques allow detailed and non-invasive characterization of bone marrow in different body regions. Low body weight (BMI<20kg/m²) has been shown to be associated with decreased bone density, while obesity has long been associated with high cortical bone mass - the idea of bone health. It has now been proven that obesity also has a negative effect on bone structure. Here, it is not only BMI that is crucial, but also the localization of fat tissue in the body. Visceral fat has a directly damaging effect on bone microarchitecture through dysregulated production and release of cytokines and adipokines. Thus, it has been shown that both type 1 and type 2 diabetic patients have a decreased rate of bone remodeling and very obese patients with type 2 diabetes have an increased risk of fracture. It must be concluded that body weight, or BMI, cannot be the sole measure for estimating bone health. Thus, type 2 diabetes shows reduced bone remodeling with normal or slightly increased bone density, but inferior stability. This means that type 2 diabetes is associated with an increased risk of osteoporotic fracture, even when bone density measurements are unremarkable. Loss of trabecular bone structure in red (hematopoietic) bone marrow is also characterized by increasing infiltration of the bone marrow space with fat cells (bone marrow adipose tissue). In contrast, the yellow bone marrow, which is mainly present in the diaphysis of tabular bones, has particularly large amounts of fat incorporated into the reticulum cells. For a long time, only the role of "placeholder" was attributed to these fat cells, but it has been shown that they interact with other cells via the production of autocrine, paracrine and endocrine hormones and cytokines, or adipokines, and are thus related to the metabolic state of the entire body. A basic assumption here is that the amount of unsaturated fatty acids in the adipose bone marrow is an important and functional marker for different types of adipocytes. It has been shown that 3 individuals with poorer insulin sensitivity have more unsaturated fatty acids in yellow bone marrow. Thus, the concept of different types of adipocytes in the bone marrow, with their inherent different fatty acid composition could serve to reconcile the at first glance counterintuitive physiological regulation of bone marrow fat and its response to metabolic perturbations. In order to show whether and how the composition of the yellow (unsaturated fatty acids) and red (bone marrow adipose tissue) bone marrow differs in healthy individuals, individuals with impaired insulin sensitivity in different age groups and patients with type 2 diabetes, and whether this can be used to detect early changes in the bone matrix with regard to bone density, the proportion of bone marrow adipose tissue in the red bone marrow at different locations in the skeleton will be quantified by means of chemical-shift-selective MRI sequences as well as the composition of bone marrow fat in the yellow bone marrow with regard to the proportions of monounsaturated and polyunsaturated fatty acids by means of volume-selective MRS. A total of 96 healthy volunteers (48 each male and female) aged 25 to 75 years and with body mass index between 18.5 and 35 kg/m² will be included. In addition, 24 patients (12female/12male) with type 2 diabetes will be recruited. After magnetic resonance examination, anthropometric and metabolic characterization (oral glucose tolerance test) will take place.
A Phase III Clinical Study of Minodronate Tablets in Postmenopausal Women With Osteoporosis
OsteoporosisIn the randomized, active-controlled, double-blinded, multicenter study, the efficacy and safety of monthly oral minodronate were examined and compared to that of weekly oral alendronate.
The Role of Incretins in Bone Remodeling in Humans
IncretinsOsteoporosis2 moreThe role of incretins (GIP and GLP-1) on cells and bone tissue has been shown in cellular and animal studies. In humans, the role of these hormones is mainly studied in the pathophysiology of diabetes, their effect on bone is unknown. The serum incretin concentration is low and increases rapidly after a meal. This increase is brief, incretins being rapidly degraded by dipeptidylpeptidase 4 (DPP-4). The dosage of these hormones is complex and the basal "normal" serum concentrations and after feeding in healthy subjects are unknown. Before any study on the effect of incretins on bone remodeling in humans, it is necessary to establish physiological concentrations of incretins in healthy subjects. The aim of this study is to estimate physiological concentrations of incretins in healthy subject.
Chinese Second Hip Fracture Evaluation
Hip FracturesOsteoporosisTo Compare overall rates of second hip fractures in both genders, To determine the effect of hip fracture on proximal femoral volumetric bone mineral density (vBMD), bone structure and muscle by quantitative computed tomography(QCT), To evaluate the contribution of QCT-image analysis to the prediction of the second hip fracture risk. To identify the differences between femoral neck fracture and trochanter fracture following hip fracture
Incidence of HANA Conditions in HIV-infected Individuals
HIVMetabolic Syndrome5 moreWith the availability of effective anti-retroviral therapy, HIV-infected individuals are expected not to die of AIDS and have longer life expectancy. But at the same time, HIV-associated non-AIDS (HANA) conditions are becoming more important in their clinical management. It is currently uncertain whether patients started on different anti-retroviral regimens will have different incidence of HANA conditions. This study aims to evaluate the incidence of various HANA conditions in a cohort of newly diagnosed HIV-infected individuals in Hong Kong initiating anti-retroviral treatment. The incidence of various HANA conditions will be evaluated for those receiving INSTI versus other non-INSTI-based regimens. The HANA conditions evaluated will include 1. Hypertension 2. Diabetes and insulin resistance 3. Dyslipidemia 4. Lipodystrophy 5. Metabolic syndrome 6. Osteopenia and osteoporosis 7. Vitamin D deficiency 8. Renal impairment and kidney tubular dysfunction and 9. Liver fibrosis. Patients will be assessed prior to initiation of anti-retroviral therapy, and 48 weeks and 96 weeks after initiation of treatment. The incidence of development of each HANA condition will be determined and compared between those initiated different anti-retroviral regimens.
The Effects of Melatonin Treatment on Bone, Marrow, Sleep and Blood Pressure
OsteoporosisPostmenopausalMelatonin protects your bones while losing fat! This was previously demonstrated by our group. The mechanisms behind these findings are still elusive, and the aim of the present study is to assess the mechanisms. In a double-blinded randomized controlled trial 40 postmenopausal woman are randomized to receive either 10 mg melatonin or placebo nightly for three months. Changes in gene expression in marrow cells will be assessed through micro array. Markers of bone metabolism will be assessed through biochemical markers. Cardiovascular health will be measured by tonometry and 24h blood pressure. The results of the study will contribute with important knowledge about the beneficial effects of melatonin making it an interesting supplement to known treatment regimens against osteoporosis and overweight.
Immunophenotyping in Patients With Osteoporosis
Immunophenotyping Blood Samples of Patients With OsteoporosisIn addition to a medical history and clinical examination, the diagnosis of osteoporosis includes the measurement of bone surface density by means of dual X-ray absorptiometry (DXA). In addition, blood tests are performed for certain parameters, such as vitamin D, calcium, phosphate and C-reactive protein. In order to optimize osteoporosis diagnostics, the development of further specific methods is required. The modulation of the immune system seems promising in this respect, since osteoporosis is based on an inflammatory reaction. Various regulatory markers of the innate and acquired immune system, which seem to be relevant in the development of the disease, have already been detected in osteoporosis patients. This study may help to gain new insights into disease-associated immunoregulatory markers that could revolutionize both the diagnosis and therapy of osteoporosis in the long term. By means of a simple blood test, patients could be diagnosed early and without additional radiation exposure, and effective therapy options could be developed.
Exercise and Posture in Individuals With Osteoporosis
OsteoporosisOsteoporosis is a common condition found in postmenopausal women. Osteoporosis increases the risk of fractures: especially hip and vertebral fractures. These fractures increase the risk of morbidity and mortality. Falls and movements that incorporate trunk flexion or rotation can increase the risk of fractures in women with osteoporosis. Weight-bearing exercise and posture training are important complementary therapies to help decrease the risk of fractures and improve the function of individuals with osteoporosis. Often in Rheumatology clinic, patient's will be given handouts concerning bone building exercises and tips on holding safe postures with activities to complete, with little follow-up of their progress or evaluation of their technique. In this study, we will compare a video-based exercise intervention with printed handout group to a handout only group and will evaluate the effectiveness of these two different modalities using physical activity measures and overall outcomes of strength and posture.
Assessment of Cortical Bone Mechanics Technology (CBMT) Fracture Discrimination Capability
OsteoporosisOsteopenia or Osteoporosis6 moreOsteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue leading to bone fragility (i.e., weakness) and an increased risk for fracture. Bone strength is a critical factor in a bone's ability to resist fracture and is clearly an important outcome in studies of osteoporosis. The current standard for assessing bone health and diagnosing osteoporosis is to use dual-energy x-ray absorptiometry (DXA) to quantify the areal bone mineral density (BMD), typically at the hip and spine. However, DXA-derived BMD has limited discriminatory accuracy for distinguishing individuals that experience fragility fracture from those who do not. One well known limitation of DXA-derived BMD is that it does not adequately assay bone strength. There is a critical unmet need to identify persons more accurately with diminished bone strength who are at high risk of experiencing a fragility fracture in order to determine an appropriate therapy. A potential new diagnostic approach to assess skeletal health and improve osteoporosis diagnosis is the use of Cortical Bone Mechanics Technology (CBMT). CBMT leverages multifrequency vibration analysis to conduct a noninvasive, dynamic 3-point bending test that makes direct, mechanical measurements of ulnar cortical bone. Data indicates that CBMT-derived ulnar flexural rigidity accurately estimates ulnar whole bone strength and provides information about cortical bone that is unique and independent of DXA-derived BMD. However, the clinical utility of CBMT-derived flexural rigidity has not yet been demonstrated. The investigators have designed a clinical study to assess the accuracy of CBMT-derived ulnar flexural rigidity in discriminating post-menopausal women who have suffered a fragility fracture from those who have not. These data will be compared to DXA-derived peripheral and central measures of BMD obtained from the same subjects.
Comparison of Efficacy of Denosumab With Eldecalcitol or Native Vitamin D in Postmenopausal Women...
Osteoporosis in Postmenopausal WomenPrimary objective: To compare the bone mineral density (BMD) change under the treatment of denosumab with eldecalcitol or native vitamin D in postmenopausal women with osteoporosis on bone mineral density. Secondary objective: To compare the efficacy of denosumab with eldecalcitol or native vitamin D treatment in postmenopausal women with osteoporosis on bone turnover markers, serum PTH, serum calcium, serum phosphorus, muscle mass, muscle strength, body balance ability, and quality of life.