Influence of daily regimen calcium and vitamin D supplementation on parathyroid hormone secretionReginster, Jean-Yves ; Zegels, Brigitte ; Lejeune, Emmanuelle et alin Calcified Tissue International (2002), 70(2), 78-82 Calcium and vitamin D supplementation has been shown to reduce secondary hyperparathyroidism and play a role in the management of senile osteoporosis. In order to define the optimal regimen of calcium and ... [more ▼] Calcium and vitamin D supplementation has been shown to reduce secondary hyperparathyroidism and play a role in the management of senile osteoporosis. In order to define the optimal regimen of calcium and vitamin D supplementation to produce the maximal inhibition of parathyroid hormone secretion, we have compared the administration of a similar amount of Ca and vitamin D, either as a single morning dose or split in two doses, taken 6 hours apart. Twelve healthy volunteers were assigned to three investigational procedures, at weekly intervals. After a blank control procedure, when they were not exposed to any drug intake, they received two calcium-vitamin D supplement regimens including either two doses of Orocal D3 (500 mg Ca and 400 IU vitamin D) 6 hours apart or one water-soluble effervescent powder pack of Cacit D3 in a single morning dose (1000 mg Ca and 880 IU vitamin D). During the three procedures (control and the two calcium-vitamin D supplementations), venous blood was drawn every 60 minutes for up to 9 hours, for serum Ca and serum PTH measurements. The order of administration of the two Ca and vitamin D supplementation sequences was allocated by randomization. No significant changes in serum Ca were observed during the study. During the 6 hours following Ca and vitamin D supplementation, a statistically significant decrease in serum PTH was observed with both regimens, compared with baseline and with the control procedure. Over this period of time, no differences were observed between the two treatment regimens. However, between the sixth and the ninth hour, serum PTH levels were still significantly decreased compared with baseline with split dose Orocal D3 administration, while they returned to baseline value with the Cacit D3 preparation. During this period, the percentage decrease in serum PTH compared with baseline was significantly more pronounced with Orocal D3 than with Cacit D3 (P = 0.0021). We therefore conclude that the administration of two doses of 500 mg of calcium and 400 IU of vitamin D3 6 hours apart provides a more prolonged decrease in serum PTH levels than the administration of the same total amount of Ca and vitamin D as a single morning dose in young healthy volunteers. This might have implications in terms of protection of the skeleton against secondary hyperparathyroidism and increased bone resorption and turnover in elderly subjects. [less ▲] Detailed reference viewed: 50 (13 ULg) Bone resorption in post-menopausal women with normal and low BMD assessed with biochemical markers specific for telopeptide derived degradation products of collagen type IReginster, Jean-Yves ; Henrotin, Yves ; et alin Calcified Tissue International (2001), 69(3), 130-137 Biochemical markers of bone resorption can be used clinically to predict the risk of osteoporosis-related fractures (prognostic tool) and to assess the response of an osteoporotic patient to an ... [more ▼] Biochemical markers of bone resorption can be used clinically to predict the risk of osteoporosis-related fractures (prognostic tool) and to assess the response of an osteoporotic patient to an antiresorptive therapy (monitoring tool). Our aim was to assess the ability of four currently marketed biochemical markers of bone resorption, based on the measurement of degradation products from collage type I telopeptides to monitor the elevated resorption associated with menopause. Women (846) were stratified for menopause, age, and bone mineral density and the following markers were measured: urinary cross-linked N-telopeptides of type I collagen (NTx), the levels of breakdown products of type I collagen C-telopeptides in serum (S-CTx), and in urine, by ELISA (U-CTx-E), and RIA (U-CTx-R). Furthermore, the ratio (a/b) between the aL form of CTx measured in the CTx RIA and the bL form measured in the ELISA was calculated. The mean difference was calculated for each marker in women with osteopenia (Op) or osteoporosis (PMO) (WHO definition) compared with healthy premenopausal (Pre) women and postmenopausal (N Post) women with normal bone mass. Serum CTx showed the highest elevation in post- compared with premenopausal women. All marker values were significantly higher in Op and PMO subjects compared with both Pre and to N Post women. Compared with premenopausal values, the largest elevation in both Op and PMO women was observed for serum CTx. Compared with N Post, urine NTx showed the highest increase in OP subjects. The a/b CTx ratio was elevated in post- compared with Pre women, but there was no difference in the ratio among N Post, Op, or PMO women. In conclusion, postmenopausal women showed elevated turnover with all bone resorption markers, but with substantial individual variation in resorption levels. Furthermore, the turnover process in postmenopausal women appears to be quantitatively different from the premenopausal stage, apparent as altered a/b CTx ratios. [less ▲] Detailed reference viewed: 19 (6 ULg) Do estrogens effectively prevent osteoporosis-related fractures?Reginster, Jean-Yves ; Bruyère, Olivier ; et alin Calcified Tissue International (2000), 67 Detailed reference viewed: 12 (6 ULg) Alphacalcidol in Prevention of Glucocorticoid-Induced OsteoporosisReginster, Jean-Yves ; ; et alin Calcified Tissue International (1999), 65(4), 328-31 One of the major drawbacks of glucocorticoids long-term therapy is the occurrence of a severe osteoporosis characterized by fractures occurring at different sites, mainly at the level of trabecular bone ... [more ▼] One of the major drawbacks of glucocorticoids long-term therapy is the occurrence of a severe osteoporosis characterized by fractures occurring at different sites, mainly at the level of trabecular bone. One of the major determinants of glucocorticoid-induced osteoporosis is a decrease in the intestinal absorption of calcium (Ca) leading to a secondary hyperparathyroidism. D-hormones have been shown to significantly improve Ca absorption in the gut and subsequently to decrease parathyroid hormone circulating levels, hence normalizing bone turnover. In a recent study evaluating 145 patients suffering from diseases requiring long-term treatment with high doses of corticosteroids, we have demonstrated a significant benefit of alphacalcidol (1 microg/day) over placebo in terms of changes in bone mineral density of the lumbar spine. These results are in accordance with studies showing better prevention of bone loss and vertebral fractures in cardiac transplant patients treated with alphacalcidol than those treated with etidronate. There is now a convergent body of evidence to suggest that alphacalcidol is a reasonable, safe, and effective option for the prevention of glucocorticoid-induced osteoporosis, provided that serum Ca is monitored on a regular basis. [less ▲] Detailed reference viewed: 16 (2 ULg) Risedronate reduces fracture risk in women with established postmenopausal osteoporosis; ; et al in Calcified Tissue International (1999), 64(S1), 43 Detailed reference viewed: 6 (2 ULg) Risedronate produces dose-dependent increases in bone mineral density in postmenopausal women with low bone mass; ; et al in Calcified Tissue International (1999), 64(S1), 69 Detailed reference viewed: 5 (2 ULg) Raloxifene therapy for 3 years reduces the risk of incident vertebral fractures in postmenopausal women; ; et al in Calcified Tissue International (1999), 64(S1), 43 Detailed reference viewed: 5 (2 ULg) Risedronate, a highly effective, short-term oral treatment for Paget’s disease: a dose-response study; ; et al in Calcified Tissue International (1999), 64 Detailed reference viewed: 3 (0 ULg) Recommendations for the registration of drugs intended for use in the treatment of male osteoporosis; ; et al in Calcified Tissue International (1999), 65 Detailed reference viewed: 1 (0 ULg) Limited clinical utility of a self-evaluating risk assessment scale for postmenopausal osteoporosis: lack of predictive value of lifestyle-related factors; Zegels, Brigitte ; et alin Calcified Tissue International (1999), 65(5), 354-358 The aim of this study was to assess the efficiency of a self-administered questionnaire to identify subjects with postmenopausal osteoporosis in the setting of first line medical care. A sample of 300 ... [more ▼] The aim of this study was to assess the efficiency of a self-administered questionnaire to identify subjects with postmenopausal osteoporosis in the setting of first line medical care. A sample of 300 postmenopausal women completed the questionnaire based on 18 items. Bone mineral density at the lumbar spine (BMD-L), total hip (BMD-H), and femoral neck (BMD-N) was used as objective criterion for evaluation. The mean risk score was 8.2 +/- 3.21. BMD was correlated with total risk score: r = -0.32 for BMD-L, -0.36 for BMD-N, and -0.43 for BMD-H. Cutoff points for the risk score (equal likelihood points) according to a T-score threshold of -2.5 were 8.6 for BMD-L and BMD-N and 9.3 for BMD-H; specificity and sensitivity was 62% and 62%, respectively, for BMD-L, 65% and 62% for BMD-N, and 75% and 63% for BMD-H. Stepwise multiple regression analysis of the questionnaire items in relation to BMD showed higher correlation coefficients for models including individual items rather than the overall risk score. Items concerning low weight, older age, and wrist fracture after 50 years of age were always selected as significant determinants of BMD (R = 0.43-0.55). Hormonal replacement therapy was also an important determinant. Lifestyle-related items did not contribute significantly. In conclusion, the diagnostic performance of the 18-item self-administered questionnaire was poorer than a shortened questionnaire omitting lifestyle factors. The clinical utility of a questionnaire should ultimately be evaluated in the specific optic of a chosen global strategy for prevention of osteoporotic fractures. [less ▲] Detailed reference viewed: 8 (4 ULg) Recommendations for the health economic analysis to be performed with a drug to be registered in prevention or treatment of osteoporosis; ; et al in Calcified Tissue International (1998), 63 Detailed reference viewed: 11 (2 ULg) Expression of Bone Sialoprotein in Human Lung CancerBellahcene, Akeila ; Maloujahmoum, Naïma ; et alin Calcified Tissue International (1997), 61(3), 183-8 Lung cancer belongs to the group of malignant lesions that specifically select bone as secondary implantation site. The molecular bases for this property, defined as osteotropism, is still largely unknown ... [more ▼] Lung cancer belongs to the group of malignant lesions that specifically select bone as secondary implantation site. The molecular bases for this property, defined as osteotropism, is still largely unknown. The recent demonstration that human breast cancer cells express and attach to bone sialoprotein (BSP), a sulfated phosphoprotein rich in bone and other mineralized tissues, could provide a clue to elucidating bone metastases formation. BSP contains the integrin binding peptide Arg-Gly-Asp (RGD), as well as non-RGD cell attachment domain. Using an immunoperoxidase technique and a specific polyclonal antibody directed against a BSP synthetic peptide, we examined the expression of BSP in 48 lung lesions including 25 squamous carcinoma, 21 adenocarcinoma, and 2 bronchioloalveolar cancers, as well as 38 human ovarian carcinoma that constitute a group of generally nonosteotropic cancers. BSP was not specifically detected in normal lung tissue with the exception of cartilage associated with bronchi. Most of the adenocarcinoma (74%) and all squamous carcinoma of the lung examined exhibited detectable levels of BSP. Staining was mainly cytoplasmic and membrane associated. The two bronchioloalveolar lung cancers examined did not show detectable amounts of BSP. When microcalcifications were observed in pulmonary malignant lesions, they were usually associated with cancer cells expressing BSP. Only 21% of the ovarian cancers examined contained malignant cells with 2+ or 3+ positivity for BSP. We further demonstrated that in 8 of 10 additional lung cancers, BSP was detected at the mRNA level. Our observation is the first demonstration that BSP is expressed in non-small cell lung carcinoma. Lung cancer cells are now the second type of osteotropic malignant cells described to express BSP. Added to the observation that BSP expression is not frequent in ovarian carcinoma, a low osteotropic cancer, our study supports our hypothesis that BSP could play a role in determining the affinity of cancer cells to bone. [less ▲] Detailed reference viewed: 23 (3 ULg) Prediction of Bone Loss Rate in Healthy Postmenopausal WomenReginster, Jean-Yves ; Deroisy, Rita ; Collette, Julien et alin Calcified Tissue International (1997), 60(3), 261-4 Prevention of fractures is the only way to drastically reduce osteoporosis-related health expenditures. In order to optimize the cost/benefit ratio of a strategy of prevention, it is essential to identify ... [more ▼] Prevention of fractures is the only way to drastically reduce osteoporosis-related health expenditures. In order to optimize the cost/benefit ratio of a strategy of prevention, it is essential to identify, as early as possible, women who will develop fractures later in their life. Therefore, and since postmenopausal bone loss is an asymptomatic process, screening procedures should detect, at the time of the menopause, women whose postmenopausal bone loss is higher than the mean, and will, a couple of years later, exhibit a low mineral content and a subsequent high risk for fractures. For 3 years we have followed a cohort of 92 healthy women who had undergone menopause less than 36 months previously. By a multivariate discriminant analysis based on the differences in lumbar bone density, assessed by dual photon absorptiometry, and in a few routine biochemical parameters (serum phosphorus, estrone, androstenedione, and urine calcium) observed during the first 6 months of the study, we have been able to correctly predict the rate of spinal bone loss, observed at the end of the 3 years, in 76% of the subjects. All of the women who presented a bone loss higher than 10% over the 3 years were correctly isolated by our discriminant functions after 6 months of follow-up. We conclude that a measurement of lumbar bone mineral density coupled with a few routine biochemical determinations, repeated twice at a 6-month interval in healthy postmenopausal women, can isolate 100% of postmenopausal "fast bone losers" with an overall specificity of 76%. [less ▲] Detailed reference viewed: 19 (5 ULg) Design for an Ipriflavone Multicenter European Fracture StudyReginster, Jean-Yves ; ; et alin Calcified Tissue International (1997), 61(Suppl 1), 28-32 In order to investigate the efficacy of ipriflavone (i.p.) on the prevention of vertebral fractures and the effect on bone mineral density (BMD) in women with postmenopausal osteoporosis, a large ... [more ▼] In order to investigate the efficacy of ipriflavone (i.p.) on the prevention of vertebral fractures and the effect on bone mineral density (BMD) in women with postmenopausal osteoporosis, a large multicentric European study was designed and is presently ongoing. Included in the study were 460 Caucasian, nonobese postmenopausal women aged > 45 and < 75 years, menopaused for at least 12 months. Inclusion was on the basis of a lumbar bone mineral density (BMD) lower than 2 SD compared with healthy women aged 50 years, corresponding to values below 0.860 g/cm2 (antero-posterior measurement) by Hologic QDR 1000. Women with prevalent vertebral fractures were excluded as well as those presenting secondary osteoporosis or having been treated with medications that could affect bone metabolism. This study was designed as a 3-year, double-blind, placebo-controlled, parallel group study that randomized the women to the oral administration of either 3 x 200 mg/day of i.p. or placebo. All patients received a daily supplement of 500 mg calcium. The primary purpose of the study was to evaluate the efficacy of i.p. in preventing vertebral nontraumatic fractures. Fracture is defined here as a > or = 20% decrease in any anterior, central, or posterior T4-L4 vertebral height. Blinded vertebral X-ray readings and vertebral morphometry have been centralized in an independent Center, with standardized evaluation of two experts. Power calculations have been based on the hypothesis that 21% of placebo-treated patients would fracture within 3 years and that treatment with i.p. would lead to a 50% reduction in the incidence of fracture. Statistical tests have been designed to have a power of 80%, with a type I error equal to 5%. Secondary endpoints were changes in vertebral, radial, and femoral BMD. Centralized controls on 100% BMD scans would ensure the good quality of BMD readings. This study should verify the hypothesis that i.p. significantly decreases the risk of vertebral fracture in postmenopausal, osteoporotic women. [less ▲] Detailed reference viewed: 5 (0 ULg) GREES recommendations for the Registration of new drugs in the prevention and treatment of osteoporosisReginster, Jean-Yves ; in Calcified Tissue International (1997), 60 Detailed reference viewed: 8 (2 ULg) Comparative analysis of healthcare use in patients with rheumatoid arthritis and control subjects without chronic diseaseEthgen, Olivier ; ; Guillemin, Francis et alin Calcified Tissue International (1997), 61 Detailed reference viewed: 14 (2 ULg) Diagnostic efficiency of a self-evaluating risk assessment for postmenopausal osteoporosis; Zegels, Brigitte ; et alin Calcified Tissue International (1997), 61 Detailed reference viewed: 16 (4 ULg) Direct social costs of Osteoporotice hip fractures in BelgiumGillet, Pierre ; Gosset, Christiane ; Reginster, Jean-Yves ![]() in Calcified Tissue International (1997), 61 Detailed reference viewed: 30 (8 ULg) Osteoporosis : The interest of a prospective visionGillet, Pierre ; Gosset, Christiane ; Reginster, Jean-Yves ![]() in Calcified Tissue International (1997), 61 Detailed reference viewed: 16 (9 ULg) Harmonization of clinical practice guidelines for the prevention and treatment of osteoporosis and osteopenia in Europe : a difficult challengeReginster, Jean-Yves ![]() in Calcified Tissue International (1996), 59(S1), 24-29 Detailed reference viewed: 3 (1 ULg) |
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