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1.	Alfredson, Håkan, et al. (författare) Bone mass in female volleyball players : a comparison of total and regional bone mass in female volleyball players and nonactive females 1997 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 60:4, s. 338-342 Tidskriftsartikel (refereegranskat)abstract The purpose of this cross-sectional study was to evaluate bone mass in female athletes participating in an impact loading sport (volleyball), and especially to investigate whether any changes in bone mass might be related to the type and magnitude of weightbearing loading and muscle strength. The volleyball group consisted of 13 first division players (age 20.9 +/- 3.7 years) training for about 8 hours/week, and the reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur, and humerus using dual-energy-X-ray absorptiometry. Isokinetic concentric peak torque of the quadricep and hamstring muscles was measured using an isokinetic dynamometer. Compared with the controls, the volleyball players had a significantly (P < 0.05-0.01) higher BMD of the total body (6.1%), lumbar spine (13.2%), femoral neck (15.8%), Ward's triangle (17.9%), trochanter (18.8%), nondominant femur (8.2%), and humerus (dominant 9.5%, nondominant 10.0%), but not of the head and the dominant whole femur. The dominant humerus showed significantly higher BMD than the nondominant humerus in both the volleyball and nonactive group (P < 0.05). There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps, and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). However, in the volleyball group there were no correlations between muscle strength and BMD of the adjacent bones, but quadricep strength correlated to BMD of the humerus. These results clearly show that young female volleyball players have a high bone mass. The demonstrated high bone mass seems to be related to the type of loading subjected to each BMD site. Muscle strength of the thigh seems to have little impact on BMD in female volleyball players.
2.	Alfredson, Håkan, et al. (författare) Bone mass in the calcaneus after heavy loaded eccentric calf-muscle training in recreational athletes with chronic achilles tendinosis 1999 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 64:5, s. 450-455 Tidskriftsartikel (refereegranskat)abstract In an ongoing prospective study of 14 recreational athletes (12 males and 2 females, mean age 44.2 +/- 7.1 years) with unilateral chronic Achilles tendinosis, we investigated the effect of treatment with heavy-loaded eccentric calf-muscle training. Pain during activity (recorded on a VAS scale) and isokinetic concentric and eccentric calf-muscle strength (peak torque at 90 degrees /second and 225 degrees /second) on the injured and noninjured side were evaluated. In this group of patients, we examined areal bone mineral density (BMD) of the calcaneus after 9 months (range 6-14 months) of training. BMD of the injured side (subjected to heavy-loaded eccentric training) was compared with BMD of the noninjured side. Before onset of heavy-loaded eccentric training, all patients had Achilles tendon pain which prohibited running activity, and significantly lower concentric and eccentric plantar flexion peak torque on the injured compared with the noninjured side. The training program consisted of 12 weeks of daily, heavy-loaded, eccentric calf-muscle training; thereafter the training was continued for 2-3 days/week. The clinical results were excellent-all 14 patients were back at their preinjury level with full running activity at the 3 month follow-up. The concentric and eccentric plantar flexion peak torque had increased significantly and did not significantly differ from the noninjured side at the 3 and 9 month follow-up. There were no significant side-to-side differences in BMD of the calcaneus. There was no significant relationship between BMD of the calcaneus and calf-muscle strength. As a comparison group, we used 10 recreational athletes (5 males and 5 females) mean age 40.9 years (range 26-55 years), who were selected for surgical treatment of chronic Achilles tendinosis localized at the 2-6 cm level. Their duration of symptoms and severity of disease were the same as in the experimental group. There were no significant side-to-side differences in BMD of the calcaneus preoperatively, but 12 months postoperatively BMD of the calcaneus was 16.4% lower at the injured side compared with the noninjured side. Heavy-loaded eccentric calf-muscle training resulted in a fast recovery in all patients, equaled the side-to-side differences in muscle strength, and was not associated with side-to-side differences in BMD of the calcaneus. In this group of middle-aged recreational athletes, BMD of the calcaneus was not related to calf-muscle strength.
3.	Alfredson, Håkan, et al. (författare) High thigh muscle strength but not bone mass in young horseback-riding females 1998 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 62:6, s. 497-501 Tidskriftsartikel (refereegranskat)abstract To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nondominant humerus, and in specific sites in the right femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric and eccentric peak torque of the quadricep and hamstring muscles were measured using an isokinetic dynamometer. There were no significant differences in bone mass between the horseback riders and nonactives at any site measured. The horse riders were significantly (P < 0.05-0.01) stronger in concentric hamstrings strength at 90 degrees/second and 225 degrees/second and in eccentric quadricep and hamstring strength at 90 degrees/second. Horseback riding in young females is associated with a high muscle strength of the thigh, but not with a high bone mass.
4.	Alfredson, Håkan, et al. (författare) Long-term loading and regional bone mass of the arm in female volleyball players 1998 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 62:4, s. 303-308 Tidskriftsartikel (refereegranskat)abstract In the present study, we compared the bone mineral content (BMC) and bone mineral density (BMD) in the arms of 11 female volleyball players (mean age 22.0 +/- 2.6 years) training for about 8 hours/week, and 11 nonactive females aged 24.6 +/- 3.1 years (mean +/- SD) not participating in regular or organized sport activity. Using dual X-ray absorptiometry (DXA), BMC was measured in the proximal and distal humerus, and BMD in the distal radius. Isokinetic concentric peak torque (highest value attained during 5 or 10 repetitions) of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow were measured using an isokinetic dynamometer. The volleyball players had significantly higher BMC (P < 0.05) at the proximal humerus of the dominant arm compared with the nonactive group, but there were no differences between the groups in BMC of the distal humerus and BMD of the distal radius. In the volleyball players, BMC was significantly higher at the proximal humerus, at the distal humerus, and at the distal radius in the dominant compared with the nondominant arm. In the nonactive group, there were no significant differences in BMC and BMD between the dominant and nondominant arm at any site measured. Except for shoulder internal rotation strength and elbow flexion strength at 90 degrees/second that was higher in the dominant arm in the volleyball players, there were no significant differences in muscle strength of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow between the dominant and nondominant arm in the volleyball players and nonactive controls. In the volleyball players, but not in the nonactive controls, there were several significant relationships between shoulder and elbow strength and BMC at the distal humerus of the dominant and especially the nondominant arm. These results show that young female volleyball players have a higher bone mass in the proximal humerus, distal humerus, and distal radius in the dominant compared with the nondominant arm, and a higher bone mass in the proximal humerus compared with nonactive controls. Muscle strength of the rotator muscles of the shoulder is not related to the higher bone mass in the proximal humerus of the dominant arm. Theoretically, the observed differences in bone mass can be related to the type of loading the skeleton undergoes when playing volleyball.
5.	Alfredson, Håkan, et al. (författare) Prolonged progressive calcaneal bone loss despite early weightbearing rehabilitation in patients surgically treated for Achilles tendinosis 1998 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 62:2, s. 166-171 Tidskriftsartikel (refereegranskat)abstract We prospectively evaluated areal bone mineral density (BMD) of the calcaneus and calf-muscle strength (concentric and eccentric plantar flexion peak torque in Nm) in 10 recreational athletes (5 males and 5 females), mean age 40.9 years (range 26-55), who were selected to undergo surgical treatment for chronic Achilles tendinosis localized at the 2-6 cm level. Surgery was followed by immobilization in a plaster cast for 2 weeks, followed by flexibility training and slowly progressing strength training and weight-bearing activity. One patient was excluded after week 0 because of a new injury. Seven patients were back to their preinjury activity at the 26-week control, and eight patients at the 52-week control postoperatively. BMD in the calcaneus and calf-muscle strength on the injured and noninjured side was measured preoperatively (week 0) and postoperatively (weeks 2, 6, 16, 26, and 52). There were no significant differences in BMD between the injured and noninjured side at weeks 0, 2, and 6, but at weeks 16, 26, and 52, BMD was significantly (P < 0.05) lower (11.5%, 18.4%, and 16.4%, respectively) in the calcaneus of the injured side. Concentric and eccentric plantar flexion strength were significantly lower on the injured side preoperatively. Eccentric, but not concentric plantar flexion strength had recovered compared with the noninjured side 1 year postoperatively. Calf-muscle strength was not related to bone mass in the calcaneus. As a comparison, we used a group of 11 recreational athletes (10 males and 1 female), with a mean age of 46.1 years (range 28.9-58.5) who had been surgically treated for chronic Achilles tendinosis at the 2-6 cm level 39.5 +/- 11.8 months ago. In this group, there was no significant difference in BMD of the calcaneus between the injured and noninjured side. It seems that there was a delayed and prolonged calcaneal bone loss despite early weightbearing loading in patients surgically treated for chronic Achilles tendinosis at the 2-6 cm level. Around that time, when the Achilles tendon had healed (4-6 months) and the athletes returned to their sports, the calcaneal bone had a relatively low BMD and might possibly be vulnerable to heavy loadings. There were no signs of recovery 1 year postoperatively, but in a comparison group there were no significant side-to-side differences 39.5 months postoperatively.
6.	Alfredson, Håkan, et al. (författare) Total and regional bone mass in female soccer players 1996 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 59:6, s. 438-442 Tidskriftsartikel (refereegranskat)abstract This cross-sectional study investigated bone mass in female athletes participating in an impact-loading sport (soccer), and evaluated whether any changes in bone mass could be related to the type of weight-bearing loading and muscle strength. The group of soccer players consisted of 16 second-division female players (age 20.9 +/- 2.2 years) training for about 6 hours/week. The reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur and humerus, and in specific sites in femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric peak torque of the quadriceps and hamstring muscles was measured using an isokinetic dynamometer. The soccer players had significantly (P < 0.05-0.01) higher BMD in the lumbar spine (10.7%), femoral neck (13.7%), Ward's triangle (19.6%), nondominant femur and humerus (8.2 and 8.0%, respectively), distal femur (12.6%), and proximal tibia (12.0%) compared with the nonactive women. There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). In the soccer group, there were no correlations between muscle strength and BMD of the adjacent and distant bones. Soccer playing and training appears to have a beneficial effect on bone mass in young females, and it seems that there is a site-specific skeletal response to the type of loading subjected to each BMD site. Muscle strength in the thigh is not related to bone mass in female soccer players.
7.	Alwis, Gayani, et al. (författare) Bone mineral accrual and gain in skeletal width in pre-pubertal school children is independent of the mode of school transportation-one-year data from the prospective observational pediatric osteoporosis prevention (POP) study (Abstracts of the 35th European Symposium on Calcified Tissues) 2008 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 82:Suppl. 1, s. 60-60 Konferensbidrag (refereegranskat)
8.	Alwis, Gayani, et al. (författare) Femoral Neck Bone Strength Estimated by Hip Structural Analysis (HSA) in Swedish Caucasians Aged 6-90 Years. 2012 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 90:3, s. 174-185 Tidskriftsartikel (refereegranskat)abstract Dual-energy X-ray absorptiometry hip scans of 1,760 population-based Caucasians, 599 girls and 642 boys aged 6-19 years and 270 women and 249 men aged 20-90 years, were analyzed with the hip structural analysis (HSA) software to present age- and sex-specific normative HSA data of the femoral neck (FN). Measured traits included bone mineral density (BMD), cross-sectional area (CSA), section modulus (Z), periosteal diameter (PD), endosteal diameter (ED), cortical thickness (CT), and cross-sectional moment of inertia (CSMI). When plotting the measured traits versus age, the curves increased with higher ages until statistically significant break points were reached, for all traits at age 17 in girls and age 19 in boys. After the break points, PD and ED increased with higher ages but, as ED increased more than PD, BMD and CT decreased significantly with higher ages. The decline in BMD was counteracted by the increase in bone size so that there was only a nonstatistically significant decrease in bone strength, estimated as Z and CSMI, from break point to age 90. The partial preservation of bone strength was more obvious in men than in women as the decline in BMD was higher in women than in men, while the expansion in PD was larger in men than in women. The sex difference in the normative FN bone strength data seems to be related to sex discrepancies in the development of both bone mass and geometrical parameters during both growth and adulthood.
9.	Alwis, Gayani, et al. (författare) Normative Calcaneal Quantitative Ultrasound Data as an Estimation of Skeletal Development in Swedish Children and Adolescents. 2010 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 87, s. 493-506 Tidskriftsartikel (refereegranskat)abstract We present age- and gender-specific normative bone status data evaluated by quantitative ultrasound (QUS) in the calcaneus with the Lunar Achilles device and compare these estimates with bone mineral content (BMC) and bone mineral density (BMD) estimated by dual X-ray absorptiometry (DXA). Included were a sample of 518 population-based collected Swedish girls and 558 boys aged 6-19 years. QUS measurements included speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI) in the calcaneus. DXA measurements included BMC and BMD in the femoral neck (FN), lumbar spine (L2-L4), and total body (TB). Height and weight were measured with standard equipment. Age, height, and weight were significantly associated with SOS, BUA, and SI. Compared to SOS, in both girls and boys there was a higher correlation between BUA and FN BMC (r = 0.71 and r = 0.73, respectively), FN BMD (r = 0.68 and r = 0.67, respectively), L2-L4 BMC (r = 0.70 and r = 0.64, respectively), L2-L4 BMD (r = 0.69 and r = 0.64, respectively), TB BMC (r = 0.76 and r = 0.75, respectively), and TB BMD (r = 0.74 and r = 0.74, respectively). The correlations between SOS and FN BMC (r = 0.38 and r = 0.52, respectively), FN BMD (r = 0.41 and r = 0.52, respectively), L2-L4 BMC (r = 0.31 and r = 0.40, respectively), L2-L4 BMD (r = 0.32 and r = 0.41, respectively), TB BMC (r = 0.42 and r = 0.49, respectively), and TB BMD (r = 0.48 and r = 0.54, respectively) were lower, although still significant (all P < 0.001). BUA seems to be the QUS parameter that best resembles the changes in BMC during growth.
10.	Baker, SM, et al. (författare) TGF-beta/extracellular matrix interactions in dentin matrix: a role in regulating sequestration and protection of bioactivity 2009 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 85:1, s. 66-74 Tidskriftsartikel (refereegranskat)
11.	Boltenstal, H, et al. (författare) Association of Serum Sclerostin with Bone Sclerostin in Chronic Kidney Disease is Lost in Glucocorticoid Treated Patients 2019 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 104:2, s. 214-223 Tidskriftsartikel (refereegranskat)
12.	Bornefalk, Eva, et al. (författare) Age-dependent effect of oral glucocorticoids on markers of bone resorption in patients with acute asthma 1998 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 63:1, s. 9-13 Tidskriftsartikel (refereegranskat)abstract It is generally accepted that bone formation is depressed during corticosteroid treatment, but the effects of glucocorticoids on bone resorption are less well characterized. We have investigated the effects of short-term treatment with high-dose oral glucocorticoids on biochemical markers of bone turnover in 20 consecutive patients with asthma who sought help for acute respiratory obstruction in our emergency department. Serum concentrations of the carboxy-terminal cross-linked telopeptide of type 1 collagen (1CTP), reflecting bone resorption, and the carboxy-terminal propeptide of type 1 procollagen (P1CP), reflecting bone formation, were measured by radioimmunoassay. Changes of the circulating levels of the bone resorption marker 1CTP after treatment were age dependent with a significant negative correlation (r = -0.54, P = 0.01). The dependency on age remained when correcting, in a multiple linear regression analysis, for 1CTP levels at admission, weight, sex, and daily maintenance dose of inhaled glucocorticoids. Circulating levels of P1CP were suppressed in the whole group 1 week after initiation of glucocorticoid therapy, from 123.3 +/- 10.2 ng/ml at admission to 88.1 +/- 6.3 ng/ml after 1 week (P < 0.01). The changes in P1CP levels were not related to age. Our data indicate that bone formation is suppressed by glucocorticoids in all age groups, whereas the effect of glucocorticoids on markers of bone resorption is dependent on age.
13.	Brage, M, et al. (författare) Different cysteine proteinases involved in bone resorption and osteoclast formation. 2005 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 76:6, s. 439-47 Tidskriftsartikel (refereegranskat)abstract Cysteine proteinases, especially cathepsin K, play an important role in osteoclastic degradation of bone matrix proteins and the process can, consequently, be significantly inhibited by cysteine proteinase inhibitors. We have recently reported that cystatin C and other cysteine proteinase inhibitors also reduce osteoclast formation. However, it is not known which cysteine proteinase(s) are involved in osteoclast differentiation. In the present study, we compared the relative potencies of cystatins C and D as inhibitors of bone resorption in cultured mouse calvariae, osteoclastogenesis in mouse bone marrow cultures, and cathepsin K activity. Inhibition of cathepsin K activity was assessed by determining equilibrium constants for inhibitor complexes in fluorogenic substrate assays. The data demonstrate that whereas human cystatins C and D are equipotent as inhibitors of bone resorption, cystatin D is 10-fold less potent as an inhibitor of osteoclastogenesis and 200-fold less potent as an inhibitor of cathepsin K activity. A recombinant human cystatin C variant with Gly substitutions for residues Arg8, Leu9, Val10, and Trp106 did not inhibit bone resorption, had 1,000-fold decreased inhibitory effect on cathepsin K activity compared to wildtype cystatin C, but was equipotent with wildtype cystatin C as an inhibitor of osteoclastogenesis. It is concluded that (i) different cysteine proteinases are likely to be involved in bone resorption and osteoclast formation, (ii) cathepsin K may not be an exclusive target enzyme in any of the two systems, and (iii) the enzyme(s) involved in osteoclastogenesis might not be a typical papain-like cysteine proteinase.
14.	Brahm, H, et al. (författare) Net fluxes over working thigh of hormones, growth factors and biomarkers of bone metabolism during short lasting dynamic exercise 1997 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 60:2, s. 175-180 Tidskriftsartikel (refereegranskat)
15.	Brahm, Helena, et al. (författare) Relationships between bone mass measurements and lifetime physical activity in a Swedish population 1998 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 62:5, s. 400-412 Tidskriftsartikel (refereegranskat)abstract Lifetime occupational and leisure time activities were assessed by a questionnaire in order to evaluate their relationship to bone mass measurements and biochemical markers of bone metabolism in a population of 61 women and 61 men, randomly selected from a Swedish population register, to represent ages between 22 and 85 years. We also considered possible confounders by using questions about smoking habits, milk consumption, hormone replacement therapy (HRT), and menopausal age. Bone mineral density (BMD) and bone mineral content (bone mass, BMC) of the total body, lumbar spine, and proximal femur (neck, trochanter, Ward's triangle) were measured by dual energy X-ray absorptiometry (DXA), and BMD of the forearm with single energy X-ray absorptiometry (SXA). In addition, both DXA and SXA provided information on bone area. Quantitative ultrasound measurements (QUS) at the heel were performed to assess the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Fasting blood samples were analyzed for biochemical markers of bone metabolism as well as parathyroid hormone (PTH) and total serum calcium. After adjustment for confounding factors, neither BMD nor QUS measurements were consistently related to lifetime leisure time or occupational activities; nor were there any consistent patterns relating biochemical markers of bone metabolism to bone mass measurements. However, physical activity seemed to influence bone mass, area, and width more than density. In men, high levels of leisure time activity were associated with raised values for lumbar spine area (6.2%) and width (3.3%) as well as for femoral neck area (5.5%) compared with their low activity counterpart. Men exposed to high levels of occupational activity demonstrated lower lumbar spine BMD (10.9%) and area (5.3%) than men with low activity levels. Within an unselected Swedish population, estimation of lifetime occupational and sport activities as well as bedrest, using a questionnaire, demonstrated no major effects on bone density. However, the association between high levels of lifetime activity and raised values for bone mass, area, and width indicate that geometrical changes in bone may provide better estimations of mechanically induced bone strength than bone density, at least in men.
16.	Brändström, Helena, et al. (författare) Single nucleotide polymorphisms in the human gene for osteoprotegerin are not related to bone mineral density or fracture in elderly women 2004 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 74:1, s. 18-24 Tidskriftsartikel (refereegranskat)abstract Osteoprotegerin (OPG), a secreted member of the tumor necrosis factor receptor family, is a potent inhibitor of osteoclast activation and differentiation. In animal models OPG prevents bone loss, and in humans bone resorption can be reduced by injections of OPG. OPG may also play a role in cardiovascular disease since mice lacking the OPG gene display arterial calcification. In a screening effort of the OPG gene, we recently discovered a single nucleotide polymorphism in the promoter region of OPG (T950C), and reported an association with vascular morphology and function in 59 healthy individuals. Due to the pronounced effect of OPG on bone turnover, the present study was conducted to investigate whether OPG polymorphisms are also associated with bone mineral density or with fracture. The relationship between single nucleotide polymorphisms in the promoter region of OPG (T950C) and the first intron (C1217T), and bone mineral density, measured by DXA in the hip or spine or ultrasound of the heel, was investigated in the Malmö OPRA-study of 1044 women, all 75 years old. The possible relation to fracture incidence was also analyzed. Among the 858 and 864 individuals respectively, genotyped, no significant associations between the investigated single nucleotide polymorphisms and bone mineral density measurements (T950C P = 0.50-0.64, C1217T P = 0.51-1.00), quantitative ultrasound measurements of the calcaneus, or fractures (T950C P = 0.61-0.66, C1217T P = 0.14-0.33) were found. Thus, our results show that polymorphisms in the OPG gene, one of which has previously been found to be associated with cardiovascular morphology and function, are not associated with bone mineral density in elderly Swedish women.
17.	Buttazzoni, Christian, et al. (författare) A Pediatric Bone Mass Scan Has Poor Ability to Predict Adult Bone Mass: A 28-Year Prospective Study in 214 Children. 2014 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 94:2, s. 232-239 Tidskriftsartikel (refereegranskat)abstract As the correlation of bone mass from childhood to adulthood is unclear, we conducted a long-term prospective observational study to determine if a pediatric bone mass scan could predict adult bone mass. We measured cortical bone mineral content (BMC [g]), bone mineral density (BMD [g/cm(2)]), and bone width (cm) in the distal forearm by single photon absorptiometry in 120 boys and 94 girls with a mean age of 10 years (range 3-17) and mean 28 years (range 25-29) later. We calculated individual and age-specific bone mass Z scores, using the control cohort included at baseline as reference, and evaluated correlations between the two measurements with Pearson's correlation coefficient. Individual Z scores were also stratified in quartiles to register movements between quartiles from growth to adulthood. BMD Z scores in childhood and adulthood correlated in both boys (r = 0.35, p < 0.0001) and girls (r = 0.50, p < 0.0001) and in both children ≥10 years at baseline (boys r = 0.43 and girls r = 0.58, both p < 0.0001) and children <10 years at baseline (boys r = 0.26 and girls r = 0.40, both p < 0.05). Of the children in the lowest quartile of BMD, 58 % had left the lowest quartile in adulthood. A pediatric bone scan with a value in the lowest quartile had a sensitivity of 48 % (95 % confidence interval [CI] 27-69 %) and a specificity of 76 % (95 % CI 66-84 %) to identify individuals who would remain in the lowest quartile also in adulthood. Childhood forearm BMD explained 12 % of the variance in adult BMD in men and 25 % in women. A pediatric distal forearm BMD scan has poor ability to predict adult bone mass.
18.	Buttazzoni, Christian, et al. (författare) A Pediatric Bone Mass Scan has Poor Ability to Predict Peak Bone Mass: An 11-Year Prospective Study in 121 Children. 2015 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 96:5, s. 379-388 Tidskriftsartikel (refereegranskat)abstract This 11-year prospective longitudinal study examined how a pre-pubertal pediatric bone mass scan predicts peak bone mass. We measured bone mineral content (BMC; g), bone mineral density (BMD; g/cm(2)), and bone area (cm(2)) in femoral neck, total body and lumbar spine by dual-energy X-ray absorptiometry in a population-based cohort including 65 boys and 56 girls. At baseline all participants were pre-pubertal with a mean age of 8 years (range 6-9), they were re-measured at a mean 11 years (range 10-12) later. The participants were then mean 19 years (range 18-19), an age range that corresponds to peak bone mass in femoral neck in our population. We calculated individual BMC, BMD, and bone size Z scores, using all participants at each measurement as reference and evaluated correlations between the two measurements. Individual Z scores were also stratified in quartiles to register movements between quartiles from pre-pubertal age to peak bone mass. The correlation coefficients (r) between pre-pubertal and young adulthood measurements for femoral neck BMC, BMD, and bone area varied between 0.37 and 0.65. The reached BMC value at age 8 years explained 42 % of the variance in the BMC peak value; the corresponding values for BMD were 31 % and bone area 14 %. Among the participants with femoral neck BMD in the lowest childhood quartile, 52 % had left this quartile at peak bone mass. A pediatric bone scan with a femoral neck BMD value in the lowest quartile had a sensitivity of 47 % [95 % confidence interval (CI) 28, 66] and a specificity of 82 % (95 % CI 72, 89) to identify individuals who would remain in the lowest quartile at peak bone mass. The pre-pubertal femoral neck BMD explained only 31 % of the variance in femoral neck peak bone mass. A pre-pubertal BMD scan in a population-based sample has poor ability to predict individuals who are at risk of low peak bone mass.
19.	Buttazzoni, Christian, et al. (författare) Preterm Children Born Small for Gestational Age are at Risk for Low Adult Bone Mass. 2016 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 98:2, s. 105-113 Tidskriftsartikel (refereegranskat)abstract Cross-sectional studies suggest that premature birth and low birth weight may both be associated with low peak bone mass. We followed bone traits in preterm individuals and controls for 27 years and examined the effects of birth weight relative to gestational age [stratified as small for gestational age (SGA) or appropriate for gestational (AGA)] on adult bone mineral density (BMD). We measured distal forearm BMC (g/cm) and BMD (g/cm(2)) with single-photon absorptiometry (SPA) in 46 preterm children (31 AGA and 15 SGA) at mean age 10.1 years (range 4-16) and in 84 healthy age-matched children. The measurements were repeated 27 years later with the same SPA apparatus but then also with dual energy absorptiometry and peripheral computed tomography (pQCT). Preterm individuals were shorter (p = 0.03) in adulthood than controls. Preterm AGA individuals had similar BMC and BMD height-adjusted Z-scores in adulthood compared to controls. Preterm SGA individuals had lower distal forearm BMC and BMD height-adjusted Z-scores in adulthood than both controls and preterm AGA individuals. Preterm SGA individuals had lower gain from childhood to adulthood in distal forearm BMC height-adjusted Z-scores than controls (p = 0.03). The deficits in preterm SGA individuals in adulthood were also captured by DEXA in height-adjusted femoral neck (FN) BMC Z-score and height-adjusted FN BMD Z-score and by pQCT in tibial cross-sectional area (CSA) Z-score and stress strain index (SSI) Z-score, where all measurements were lower than controls (all p values <0.05). Preterm SGA individuals are at increased risk of reaching low adult bone mass, at least partly due to a deficit in the accrual of bone mineral during growth. In our cohort, we were unable to find a similar risk in preterm AGA individuals.
20.	Callréus, Mattias, et al. (författare) Adverse Effects of Smoking on Peak Bone Mass May Be Attenuated by Higher Body Mass Index in Young Female Smokers. 2013 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 93:6, s. 517-525 Tidskriftsartikel (refereegranskat)abstract Smoking is associated with postmenopausal bone loss and fracture, but the effect of smoking on bone in younger women is unclear. Peak bone mass is an important determinant for fracture risk; therefore, our aim was to evaluate the association between smoking and bone mass in 25-year-old women, specifically the influence of daily cigarette consumption and total exposure, duration, age at starting smoking, and time since smoking cessation on bone density and fracture risk. Smoking and bone mineral density (BMD) data were available for 1,054 women from the PEAK-25 cohort. Analyses comparing current smokers with women who never smoked were performed using number of cigarettes per day, pack-years, smoking duration, age smoking started, and, for former smokers, age at quitting. BMD did not differ between never, former, and current smokers; and the relative fracture risk in smokers was not significant (relative risk [RR] = 1.2, 95 % confidence interval 0.8-1.9). Among current smokers, BMD decreased with a dose response as cigarette consumption increased (femoral neck p = 0.037). BMD was not significantly lower in young women who had smoked for long duration or started smoking early (p = 0.07-0.64); long duration and early start were associated with higher body mass index (BMI; p = 0.038). Lower BMD persisted up to 24 months after smoking cessation (p = 0.027-0.050), becoming comparable to never-smokers after 24 months. Hip BMD was negatively associated with smoking and dose-dependent on cigarette consumption. Smoking duration was not associated with BMD, although young women with a long smoking history had higher BMI, which might attenuate the adverse effects from smoking.
21.	Costa, Adriana, et al. (författare) PLS3 Mutations in X-Linked Osteoporosis : Clinical and Genetic Features in Five New Families 2023 Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 114, s. 157-170 Tidskriftsartikel (refereegranskat)abstract Childhood-onset osteoporosis is a rare but clinically significant condition. Studies have shown pathogenic variants in more than 20 different genes as causative for childhood-onset primary osteoporosis. The X-chromosomal PLS3, encoding Plastin-3, is one of the more recently identified genes. In this study, we describe five new families from four different European countries with PLS3-related skeletal fragility. The index cases were all hemizygous males presenting with long bone and vertebral body compression fractures. All patients had low lumbar spine bone mineral density (BMD). The age at the first clinical fracture ranged from 1.5 to 13 years old. Three of the identified PLS3 variants were stop-gain variants and two were deletions involving either a part or all exons of the gene. In four families the variant was inherited from the mother. All heterozygous women reported here had normal BMD and no bone fractures. Four patients received bisphosphonate treatment with good results, showing a lumbar spine BMD increment and vertebral body reshaping after 10 months to 2 years of treatment. Our findings expand the genetic spectrum of PLS3-related osteoporosis. Our report also shows that early treatment with bisphosphonates may influence the disease course and reduce the progression of osteoporosis, highlighting the importance of early diagnosis for prompt intervention and appropriate genetic counseling.
22.	Costantini, A, et al. (författare) Autosomal Recessive Osteogenesis Imperfecta Caused by a Novel Homozygous COL1A2 Mutation 2018 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 103:3, s. 353-358 Tidskriftsartikel (refereegranskat)
23.	Cronin, O., et al. (författare) Role of the Microbiome in Regulating Bone Metabolism and Susceptibility to Osteoporosis 2022 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 110:3, s. 273-284 Tidskriftsartikel (refereegranskat)abstract The human microbiota functions at the interface between diet, medication-use, lifestyle, host immune development and health. It is therefore closely aligned with many of the recognised modifiable factors that influence bone mass accrual in the young, and bone maintenance and skeletal decline in older populations. While understanding of the relationship between micro-organisms and bone health is still in its infancy, two decades of broader microbiome research and discovery supports a role of the human gut microbiome in the regulation of bone metabolism and pathogenesis of osteoporosis as well as its prevention and treatment. Pre-clinical research has demonstrated biological interactions between the microbiome and bone metabolism. Furthermore, observational studies and randomized clinical trials have indicated that therapeutic manipulation of the microbiota by oral administration of probiotics may influence bone turnover and prevent bone loss in humans. In this paper, we summarize the content, discussion and conclusions of a workshop held by the Osteoporosis and Bone Research Academy of the Royal Osteoporosis Society in October, 2020. We provide a detailed review of the literature examining the relationship between the microbiota and bone health in animal models and in humans, as well as formulating the agenda for key research priorities required to advance this field. We also underscore the potential pitfalls in this research field that should be avoided and provide methodological recommendations to facilitate bridging the gap from promising concept to a potential cause and intervention target for osteoporosis.
24.	den Bussche, K., et al. (författare) Influence of Birth Weight on Calcaneal Bone Stiffness in Belgian Preadolescent Children 2012 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 91:4, s. 267-275 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to investigate the relation between birth weight and calcaneal bone stiffness in a large sample of Belgian, healthy, preadolescent children. Participants were 827 children (3.6-11.2 years, 51.6 % boys) from the Belgian cohort of the IDEFICS study. Birth weight was obtained using a parental questionnaire, and quantitative ultrasound (QUS) measurements were performed to determine calcaneal broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) using the Lunar Achilles device. Average birth weights were 3435.7 +/- A 512.0 g for boys and 3256.9 +/- A 471.1 g for girls. Average calcaneal QUS measurements were 89.6 +/- A 24.0 (23.3-153.9) dB/MHz for BUA, 1621.4 +/- A 49.6 (1516.3-1776.5) m/s for SOS, and 92.8 +/- A 15.6 (49.0-163.0) for SI. Birth weight was positively associated with BUA (r = 0.13, p = 0.002) and SOS (r = -0.16, p < 0.001). The associations remained after correcting for age and sex in multiple regression analyses but disappeared after correcting for anthropometric covariates. Our findings suggest that birth weight, as a rough proxy indicator for genetic and environmental influences during intrauterine life, is associated with BUA and SOS in preadolescent children and may therefore influence the risk of osteoporosis later in life. Further studies using QUS are needed to investigate the consistency of the results of this study.
25.	Detter, Fredrik, et al. (författare) A 5-Year Exercise Program in Pre- and Peripubertal Children Improves Bone Mass and Bone Size Without Affecting Fracture Risk. 2013 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 92:4, s. 385-393 Tidskriftsartikel (refereegranskat)abstract We studied the effect in children of an exercise intervention program on fracture rates and skeletal traits. Fractures were registered for 5 years in a population-based prospective controlled exercise intervention study that included children aged 6-9 years at study start, 446 boys and 362 girls in the intervention group and 807 boys and 780 girls in the control group. Intervention subjects received 40 min/school day of physical education and controls, 60 min/week. In 73 boys and 48 girls in the intervention group and 52 boys and 48 girls in the control group, bone mineral density (BMD, g/cm(2)) and bone area (mm(2)) were followed annually by dual-energy X-ray absorptiometry, after which annual changes were calculated. At follow-up we also assessed trabecular and cortical volumetric BMD (g/cm(3)) and bone structure by peripheral computed tomography in the tibia and radius. There were 20.0 fractures/1,000 person-years in the intervention group and 18.5 fractures/1,000 person-years in the control group, resulting in a rate ratio of 1.08 (0.79-1.47) (mean and 95 % CI). The gain in spine BMD was higher in both girls (difference 0.01 g/cm(2), 0.005-0.019) and boys (difference 0.01 g/cm(2), 0.001-0.008) in the intervention group. Intervention girls also had higher gain in femoral neck area (difference 0.04 mm(2), 0.005-0.083) and at follow-up larger tibial bone mineral content (difference 0.18 g, 0.015-0.35), larger tibial cortical area (difference 17 mm(2), 2.4-31.3), and larger radial cross-sectional area (difference 11.0 mm(2), 0.63-21.40). As increased exercise improves bone mass and in girls bone size without affecting fracture risk, society ought to encourage exercise during growth.
26.	Døvling Kaspersen, Jørn, et al. (författare) Small-Angle X-ray Scattering Demonstrates Similar Nanostructure in Cortical Bone from Young Adult Animals of Different Species. 2016 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. Tidskriftsartikel (refereegranskat)abstract Despite the vast amount of studies focusing on bone nanostructure that have been performed for several decades, doubts regarding the detailed structure of the constituting hydroxyapatite crystal still exist. Different experimental techniques report somewhat different sizes and locations, possibly due to different requirements for the sample preparation. In this study, small- and wide-angle X-ray scattering is used to investigate the nanostructure of femur samples from young adult ovine, bovine, porcine, and murine cortical bone, including three different orthogonal directions relative to the long axis of the bone. The radially averaged scattering from all samples reveals a remarkable similarity in the entire q range, which indicates that the nanostructure is essentially the same in all species. Small differences in the data from different directions confirm that the crystals are elongated in the [001] direction and that this direction is parallel to the long axis of the bone. A model consisting of thin plates is successfully employed to describe the scattering and extract the plate thicknesses, which are found to be in the range of 20-40 Å for most samples but 40-60 Å for the cow samples. It is demonstrated that the mineral plates have a large degree of polydispersity in plate thickness. Additionally, and equally importantly, the scattering data and the model are critically evaluated in terms of model uncertainties and overall information content.
27.	Egund, Lisa, et al. (författare) High Prevalence of Osteoporosis in Men with Distal Radius Fracture : A Cross-Sectional Study of 233 Men 2016 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 99:3, s. 250-258 Tidskriftsartikel (refereegranskat)abstract Distal radius fracture is an early indicator of osteoporosis, yet little is known about men with this fracture and osteoporosis prevalence. The purpose of this cross-sectional, controlled study was to evaluate bone mineral density (BMD) in men, from working age to the elderly, with distal radius fracture. Recruitment was as follows: men who fractured during 1999–2000 were evaluated retrospectively in 2003 and men who fractured during 2003–2007 were followed prospectively for one year post-fracture. A total of 233 patients, response rate 40 %, were enrolled and compared with 643 controls. Fractures from all degrees of trauma were included. BMD was measured at femoral neck, total hip, and lumbar spine. Mean age at fracture was 52 years (21–88 years). Men aged 40–64 years had 5.4–6.7 % lower BMD at all sites compared to controls (p = 0.001) and in >65 years BMD was lower by 10.7–13.8 % (p <0.001), while not significant at 65 years: 23.3 vs 8.3 %) BMD did not differ with trauma level. Already from age 40, men with a distal radius fracture had lower BMD, the difference becoming more pronounced with increasing age. Also, the prevalence of osteoporosis was higher, surprisingly even in the youngest age group.
28.	Eklund, Fredrik, et al. (författare) Variation in fracture rates by country may not be explained by differences in bone mass 2009 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 85:1, s. 10-16 Tidskriftsartikel (refereegranskat)abstract It is unclear whether the high fracture incidence in Sweden compared with other countries is related to low bone mass. We present and compare bone mineral density (BMD, g/cm(2)) at the femoral neck in a mainly osteoporotic referral population consisting of 2,031 men and 6,932 women with that of previous population-based cohorts. BMD measurements were collected at a single study center in Sweden, and data on validated hip fractures were collected from the corresponding health-care district and the cohort investigated. The BMD values of our cohort were similar to those of population-based cohorts from other countries. In contrast, the total incidence of hip fractures in 80-year-old women and men in the health-care district where our BMD measurements were performed was high (1.8% and 0.9%, respectively). The correlation between age and BMD was more negative in men aged 20-49 years than in women of the same age group (-0.011 vs. -0.006 g/cm(2) yearly, P < 0.001). In contrast, at 50-80 years of age, more negative regression coefficients were seen in women (-0.007 vs. -0.004 g/cm(2) yearly, P < 0.001 for comparison). In conclusion, a low BMD may not be the key factor explaining Sweden's comparatively high fracture incidence. In our cross-sectional data, age trends in BMD at the femoral neck differ between men and women. It would be highly interesting to further study the underlying causes of the global variations in fracture incidence rates.
29.	Ekman, S, et al. (författare) Ultrastructural immunolocalization of cartilage oligomeric matrix protein (COMP) in porcine growth cartilage 1997 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 60:6, s. 547-553 Tidskriftsartikel (refereegranskat)
30.	Farley, JR, et al. (författare) Effects of tunicamycin, mannosamine, and other inhibitors of glycoprotein processing on skeletal alkaline phosphatase in human osteoblast-like cells 2005 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 76:1, s. 63-74 Tidskriftsartikel (refereegranskat)abstract Skeletal alkaline phosphatase (sALP) is a glycoprotein - ∼20% carbohydrate by weight, with five presumptive sites for N-linked glycosylation, as well as a carboxy-terminal site for attachment of the glycolipid structure (glycosylphosphatidylinositol, GPI), which anchors sALP to the outer surface of osteoblasts. The current studies were intended to characterize the effects of inhibiting glycosylation and glycosyl-processing on the synthesis, plasma membrane attachment, cellular-extracellular distribution, and reaction kinetics of sALP in human osteosarcoma (SaOS-2) cells. sALP synthesis, glycosylation, and GPI-anchor attachment were assessed as total protein synthesis/immunospecific sALP synthesis, sialic acid content (i.e., wheat germ agglutinin precipitation), and insolubility (i.e., temperature-dependent phase-separation), respectively. sALP reaction kinetics were characterized by analysis of dose-dependent initial velocity data, with a phosphoryl substrate. The results of these studies revealed that the inhibition of either N-linked glycosylation or oligosaccharide synthesis for GPI-anchor addition could affect the synthesis and the distribution of sALP, but not the kinetics of the phosphatase reaction. Tunicamycin - which blocks N-linked glycosylation by inhibiting core oligosaccharide synthesis - decreased cell layer protein and the total amount of sALP in the cells, while increasing the relative level of sALP in the cell-conditioned culture medium (CM, i.e., the amount of sALP released). These effects were attributed to dose- and time-dependent decreases in sALP synthesis and N-linked glycosylation, and an increase in apoptotic cell death (P < 0.001 for each). In contrast to the effects of tunicamycin on N-linked glycosylation, the effects of mannosamine, which inhibits GPI-anchor glycosylation/formation, included (1) an increase in cell layer protein, (2) decreases in sALP specific activity, in the cells and in the CM, and (3) increases in the percentages of both anchorless and wheat germ agglutinin (WGA)-soluble sALP in the medium, but not in the cells (P < 0.005 for each). These effects of mannosamine were, presumably, a consequence of inhibiting the insertion/attachment of sALP to the outside of the plasma membrane surface. Neither mannosammine nor tunicamycin had any effect on the reaction kinetics of sALP or on the apparent affinity (the value of KM) for the phosphoryl substrate.
31.	Flodgren, G, et al. (författare) Bone mineral density in flatwater sprint kayakers. 1999 Ingår i: Calcified Tissue International. - 0171-967X .- 1432-0827. ; 64:5, s. 374-379 Tidskriftsartikel (refereegranskat)abstract To elucidate the possible skeletal benefits of the muscular contractions and the nonweight-bearing loading pattern associated with kayaking, we investigated the bone mineral density (BMD, g/cm2) of 10 elite kayakers, six males and four females, with a median age of 19 years. Each subject was compared with the mean value of two matched controls. BMD of the total body, head, ribs, humerus, legs, proximal femur (neck, wards, trochanter), spine, lumbar spine, and bone mineral content (BMC, g), of the arms was obtained using a dual energy X-ray absorptiometer (DXA). Body composition was also assessed. The kayakers had a significantly (P < 0.05-0.01) greater BMD in most upper body sites: left and right humerus (10.4% and 11. 7%), respectively, ribs (6.4%), spine (10.9%), and a greater BMC of the left and right arm (15.7% and 10.6%, respectively). No significant differences in the BMD of the total body, head, or any of the lower body sites were found, except for the pelvis, which was significantly greater in kayakers (5.1%). The controls had a significantly lesser lean body mass (10.4%) and greater percentage of body fat (19.5%) than the kayakers. Bivariate correlation analysis in the controls demonstrated significant and strong relationships between BMD in upper body sites and lean body mass, weight, and fat; the effects of training seem to outweigh most such relationships in kayakers. In conclusion, it seems that the loading pattern and muscular contractions associated with kayaking may result in site-specific adaptations of the skeleton.
32.	Franceschi, R, et al. (författare) Idiopathic Juvenile Osteoporosis: Clinical Experience from a Single Centre and Screening of LRP5 and LRP6 Genes 2015 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 96:6, s. 575-579 Tidskriftsartikel (refereegranskat)
33.	Fritz, Jesper, et al. (författare) Influence of a School-based Physical Activity Intervention on Cortical Bone Mass Distribution : A 7-year Intervention Study 2016 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 99:5, s. 443-453 Tidskriftsartikel (refereegranskat)abstract Cortical bone mass and density varies across a bones length and cross section, and may be influenced by physical activity. This study evaluated the long-term effects of a pediatric school-based physical activity intervention on tibial cortical bone mass distribution. A total of 170 children (72 girls and 98 boys) from one school were provided with 200 min of physical education per week. Three other schools (44 girls and 47 boys) continued with the standard 60 min per week. Tibial total and cortical area, cortical density, polar stress–strain index (SSI), and the mass and density distribution around the center of mass (polar distribution, mg) and through the bones cortex (radial distribution subdivided into endo-, mid-, and pericortical volumetric BMD: mg/cm3) at three sites (14, 38, and 66 %) were assessed using peripheral quantitative computed tomography after 7 years. Girls in the intervention group had 2.5 % greater cortical thickness and 6.9 % greater SSI at the 66 % tibia, which was accompanied by significantly greater pericortical volumetric BMD compared to controls (all P <0.05). Region-specific differences in cortical mass were also detected in the anterior, medial, and lateral sectors at the 38 and 66 % tibial sites. There were no group differences at the 14 % tibia site in girls, and no group differences in any of the bone parameters in boys. Additional school-based physical education over seven years was associated with greater tibial structure, strength, and region-specific adaptations in cortical bone mass and density distribution in girls, but not in boys.
34.	Gagnemo-Persson, R, et al. (författare) Chicken parathyroid hormone gene expression in response to gastrin, omeprazole, ergocalciferol, and restricted food intake 1997 Ingår i: Calcified Tissue International. - 0171-967X .- 1432-0827. ; 61:3, s. 210-215 Tidskriftsartikel (refereegranskat)
35.	Gerdhem, Paul, et al. (författare) Association of the collagen type 1 (COL1A 1) Sp1 binding site polymorphism to femoral neck bone mineral density and wrist fracture in 1044 elderly Swedish women 2004 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 74:3, s. 264-269 Tidskriftsartikel (refereegranskat)abstract Identification of risk factors for osteoporosis has been essential for understanding the development of osteoporosis and related fragility fractures. A polymorphism of the binding site for the transcription factor Sp1 of the collagen I alpha 1 gene (COLIA1) has shown an association to bone mass and fracture, but the findings have not been consistent, which may be related to population differences. The Sp1 polymorphism was determined in 1044 women, all 75 years old, participating in the population-based Osteoporosis Prospective Risk Assessment study in Malmö (OPRA). Bone mineral density, heel ultrasound and all previous fractures were registered. BMD was 2.7% lower in the femoral neck in women carrying at least one copy of the "s" allele ( P = 0.027). There was no difference in bone mass at any other site, weight, BMI or age at menopause. Women with a prevalent wrist fracture (n = 181) had an increased presence of the "s" allele. The odds ratio for prevalent wrist fracture was 2.73 (95% CI 1.1-6.8) for the ss homozygotes and 1.4 (95% CI 1.0-2.0) for the Ss heterozygotes when compared with the SS homozygotes. In conclusion, in this large and homogeneous cohort of 75-year-old Swedish women, there was an association among the Sp1 COLIA1 polymorphism, bone mass, and fracture. The presence of at least one copy of the "s" allele was associated with lower femoral neck BMD and previous wrist fracture and in addition, it was related to an increased risk for wrist fracture.
36.	Grundberg, Elin, et al. (författare) A poly adenosine repeat in the human vitamin D receptor gene is associated with bone mineral density in young Swedish women 2003 Ingår i: Calcified Tissue International. - 0171-967X .- 1432-0827. ; 73, s. 455- Tidskriftsartikel (refereegranskat)
37.	Halling Linder, Cecilia, et al. (författare) Bone Alkaline Phosphatase and Tartrate-Resistant Acid Phosphatase: Potential Co-regulators of Bone Mineralization 2017 Ingår i: Calcified Tissue International. - : SPRINGER. - 0171-967X .- 1432-0827. ; 101:1, s. 92-101 Tidskriftsartikel (refereegranskat)abstract Phosphorylated osteopontin (OPN) inhibits hydroxyapatite crystal formation and growth, and bone alkaline phosphatase (BALP) promotes extracellular mineralization via the release of inorganic phosphate from the mineralization inhibitor inorganic pyrophosphate (PPi). Tartrate-resistant acid phosphatase (TRAP), produced by osteoclasts, osteoblasts, and osteocytes, exhibits potent phosphatase activity towards OPN; however, its potential capacity as a regulator of mineralization has not previously been addressed. We compared the efficiency of BALP and TRAP towards the endogenous substrates for BALP, i.e., PPi and pyridoxal 5-phosphate (PLP), and their impact on mineralization in vitro via dephosphorylation of bovine milk OPN. TRAP showed higher phosphatase activity towards phosphorylated OPN and PPi compared to BALP, whereas the activity of TRAP and BALP towards PLP was comparable. Bovine milk OPN could be completely dephosphorylated by TRAP, liberating all its 28 phosphates, whereas BALP dephosphorylated at most 10 phosphates. OPN, dephosphorylated by either BALP or TRAP, showed a partially or completely attenuated phosphorylation-dependent inhibitory capacity, respectively, compared to native OPN on the formation of mineralized nodules. Thus, there are phosphorylations in OPN important for inhibition of mineralization that are removed by TRAP but not by BALP. In conclusion, our data indicate that both BALP and TRAP can alleviate the inhibitory effect of OPN on mineralization, suggesting a potential role for TRAP in skeletal mineralization. Further studies are warranted to explore the possible physiological relevance of TRAP in bone mineralization.
38.	Halling Linder, Cecilia, et al. (författare) Glycation Contributes to Interaction Between Human Bone Alkaline Phosphatase and Collagen Type I 2016 Ingår i: Calcified Tissue International. - : Springer-Verlag New York. - 0171-967X .- 1432-0827. ; 98:3, s. 284-293 Tidskriftsartikel (refereegranskat)abstract Bone is a biological composite material comprised primarily of collagen type I and mineral crystals of calcium and phosphate in the form of hydroxyapatite (HA), which together provide its mechanical properties. Bone alkaline phosphatase (ALP), produced by osteoblasts, plays a pivotal role in the mineralization process. Affinity contacts between collagen, mainly type II, and the crown domain of various ALP isozymes were reported in a few in vitro studies in the 1980s and 1990s, but have not attracted much attention since, although such interactions may have important implications for the bone mineralization process. The objective of this study was to investigate the binding properties of human collagen type I to human bone ALP, including the two bone ALP isoforms B1 and B2. ALP from human liver, human placenta and E. coli were also studied. A surface plasmon resonance-based analysis, supported by electrophoresis and blotting, showed that bone ALP binds stronger to collagen type I in comparison with ALPs expressed in non-mineralizing tissues. Further, the B2 isoform binds significantly stronger to collagen type I in comparison with the B1 isoform. Human bone and liver ALP (with identical amino acid composition) displayed pronounced differences in binding, revealing that post-translational glycosylation properties govern these interactions to a large extent. In conclusion, this study presents the first evidence that glycosylation differences in human ALPs are of crucial importance for protein–protein interactions with collagen type I, although the presence of the ALP crown domain may also be necessary. Different binding affinities among the bone ALP isoforms may influence the mineral-collagen interface, mineralization kinetics, and degree of bone matrix mineralization, which are important factors determining the material properties of bone.
39.	Hasselstrom, H. A., et al. (författare) A 3-year Physical Activity Intervention Program Increases the Gain in Bone Mineral and Bone Width in Prepubertal Girls but not Boys: The Prospective Copenhagen School Child Interventions Study (CoSCIS) 2008 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 83:4, s. 243-250 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to evaluate the effect of increasing the amount of time spent in physical education classes on bone mineral accrual and gain in bone size in prepubertal Danish children. A total of 135 boys and 108 girls, aged 6-8 years, were included in a school-based curriculum intervention program where the usual time spent in physical education classes was doubled to four classes (180 min) per week. The control group comprised age-matched children (62 boys and 76 girls) recruited from a separate community who completed the usual Danish school curriculum of physical activity (90 min/week). Dual-energy X-ray absorptiometry was used to evaluate bone mineral content (BMC; g), bone mineral density (g/cm(2)), and bone width at the calcaneus and distal forearm before and after 3 years of intervention. Anthropometrics and Tanner stages were evaluated on the same occasions. General physical activity was measured with an accelerometer worn for 4 days. In girls, the intervention group had a 12.5% increase (P = 0.04) in distal forearm BMC and a 13.2% increase (P = 0.005) in distal forearm scanned area compared with girls in the control group. No differences were found between the intervention and control groups in boys. Increasing the frequency of physical education classes for prepubertal children is associated with a higher accrual of bone mineral and higher gain in bone size after 3 years in girls but not in boys.
40.	Hasselstrom, H., et al. (författare) Peripheral bone mineral density and different intensities of physical activity in children 6-8 years old: The Copenhagen School Child Intervention Study 2007 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 80:1, s. 31-38 Tidskriftsartikel (refereegranskat)abstract This study aimed to evaluate the association between objectively measured habitual physical activity and calcaneal and forearm bone mineral density (BMD, g/cm(2)), one mechanically more loaded and one less loaded skeletal region, in children aged 6-8 years. BMD was measured in 297 boys and 265 girls by peripheral dual-energy X-ray absorptiometry in the forearm and calcaneus. An accelerometer registered the level of physical activity during 4 days (2 weekdays and the weekend). Weight, height, and skinfold thickness were measured. In order to establish thresholds (count center dot min(-1)) for bone-stimulating physical activity, we evaluated different definitions of vigorous physical activity. The boys had 3.2% higher distal forearm bone mineral content (BMC, P < 0.001) and 4.5% higher distal forearm BMD (P < 0.001) than the girls. They also carried out 9.7% more daily physical activity and spent 14.6-19.0% more time in vigorous physical activity (all P < 0.05) compared to the girls. In contrast, the girls had 3.8% higher calcaneal BMC (P < 0.01) and 2.5% higher calcaneal BMD (P < 0.05) than the boys. Both calcaneal and forearm BMD were significantly related to total time of daily physical activity as well as with intense physical activity above all the chosen cut-off points (all P < 0.05). The beta value for mean count center dot min(-1) physical activity was significantly lower than that for all the chosen cut-off points of vigorous activity both for calcaneal and distal forearm BMD. This study suggests that both habitual daily physical activity and amount of vigorous physical activity in children aged 6-8 years are associated with appendicular BMD.
41.	Hasselstrom, H., et al. (författare) Sex differences in bone size and bone mineral density exist before puberty. The Copenhagen School Child Intervention Study (CoSCIS) 2006 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 79:1, s. 7-14 Tidskriftsartikel (refereegranskat)abstract Background: The aim of this study was to provide normative data of bone mineral density (BMD; g/cm(2)) of the forearm and the calcaneus, evaluated by peripheral dual X ray absorbtiometry (DXA), in children aged 6 to 7 years of age and to evaluate the association with anthropometrics and sex. Materials and methods: 368 boys and 326 girls with a mean age of 6.7 +/- 0.4 years participated. BMD was measured by DXA in the forearms and the os calcanei, with average values presented in this report. Measurements of weight, height, skinfolds, the width of distal radius and ulna, and the femur condyles were collected and body composition estimated from skinfolds measurements. Results: There was no difference in calcaneus BMD when comparing boys and girls, whereas the boys had 4.5% (0.013 g/cm(2)) higher forearm BMD than the girls (P < 0.001). Calcaneal BMD (mean 0.318 g/cm(2)) was 11% higher than forearm BMD (mean 0.283 g/cm(2)). Linear relationship was found between calcaneus BMD and weight (partial r = 0.50), Fat free mass (FFM) (partial r = 0.50), Fat mass (FM) (partial r = 0.45), % body fat (partial r = 0.29) and knee width (partial r = 0.46), all P < 0.000 respectively. Adjusted for weight the relationship between calcaneus BMD and FFM, FM, %body fat and knee width disappeared. There were significant relationships between the forearm BMD and weight (partial r = 0.37), FFM (partial r = 0.39), FM (partial r = 0.28), %body fat (partial r = 0.14) and wrist width (partial r = 0.24), all P < 0.000 respectively. Adjusted for body weight, the relationship remained between forearm BMD and FFM (r = 0.10), FM (R = -0.10) and % body fat (r = -0.12), all P < 0.000 respectively. Children measured in the spring had 3.5% (P < 0.01) higher calcaneus BMD than children measured in the winter. Conclusion: Seven year old boys have higher BMD in the forearm but not in the calcaneus in comparison with girls of a similar age. Body weight is the best predictor of calcaneus BMD, accounting for 25% of the variance whereas body weight and FFM are the best predictors of forearm BMD, each accounting for 17% of the variance, respectively.
42.	Hasserius, Ralph, et al. (författare) Long-Term Morbidity and Mortality After a Clinically Diagnosed Vertebral Fracture in the Elderly-a 12- and 22-Year Follow-up of 257 Patients. 2005 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 76:4, s. 235-242 Tidskriftsartikel (refereegranskat)
43.	Hill, Tom R., et al. (författare) A Vitamin D, Calcium and Leucine-Enriched Whey Protein Nutritional Supplement Improves Measures of Bone Health in Sarcopenic Non-Malnourished Older Adults : The PROVIDE Study 2019 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 105:4, s. 383-391 Tidskriftsartikel (refereegranskat)abstract Alterations in musculoskeletal health with advanced age contribute to sarcopenia and decline in bone mineral density (BMD) and bone strength. This decline may be modifiable via dietary supplementation. To test the hypothesis that a specific oral nutritional supplement can result in improvements in measures of bone health. Participants (n 380) were participants of the PROVIDE study, a 13-week, multicenter, randomized, controlled, double-blind, 2 parallel-group study among non-malnourished older participants (≥ 65 years) with sarcopenia [determined by Short Physical Performance Battery (SPPB; 0-12) scores between 4 and 9, and a low skeletal muscle mass index (SMI; skeletal muscle mass/BW × 100) ≤ 37% in men and ≤ 28% in women using bioelectric impedance analysis] Supplementation of a vitamin D, calcium and leucine-enriched whey protein drink that comprises a full range of micronutrients (active; 2/day) was compared with an iso-caloric control. Serum 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), biochemical markers of bone formation (osteocalcin; OC, procollagen type 1 amino-terminal propeptide; P1NP) and resorption (carboxy-terminal collagen crosslinks; CTX), insulin like growth factor 1 (IGF-1) and total-body BMD were analysed pre- and post-intervention. Serum 25(OH)D concentrations increased from 51.1 ± 22.9 nmol/L (mean ± SD) to 78.9 ± 21.1 nmol/L in the active group (p < 0.001 vs. control). Serum PTH showed a significant treatment difference (p < 0.001) with a decline in the active group, and increase in the control group. Serum IGF-1 increased in the active group (p < 0.001 vs. control). Serum CTX showed a greater decline in the active group (p = 0.001 vs. control). There were no significant differences in serum OC or P1NP between groups during the intervention. Total body BMD showed a small (0.02 g/cm2; ~ 2%) but significant increase in the active group after supplementation (p = 0.033 vs. control). Consuming a vitamin D, calcium and leucine-enriched whey protein supplement for 13 weeks improved 25(OH)D, suppressed PTH and had small but positive effects on BMD, indicative of improved bone health, in sarcopenic non-malnourished older adults.
44.	Högström, Magnus, et al. (författare) Relationship between vitamin D metabolites and bone mineral density in young males : a cross-sectional and longitudinal study. 2006 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 79:2, s. 95-101 Tidskriftsartikel (refereegranskat)
45.	Ivaska, Kaisa K., et al. (författare) Bone Turnover Marker Profiling and Fracture Risk in Older Women : Fracture Risk from Age 75 to 90 2022 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 111:3, s. 288-299 Tidskriftsartikel (refereegranskat)abstract Purpose: A major challenge in osteoporosis is to identify individuals at high fracture risk. We investigated six bone turnover markers (BTMs) to determine association with specific fracture types; the time-frame for risk prediction and whether these are influenced by age at assessment. Methods: Population-based OPRA cohort (n = 1044) was assessed at ages 75, 80, 85 and fractures documented for up to 15 years. Six BTMs were analyzed at each time-point (N-terminal propeptide of type I collagen, PINP; total osteocalcin, OC; bone-specific alkaline phosphatase, BALP; C-terminal telopeptide of type I collagen, CTX; tartrate-resistant acid phosphatase 5b, TRAcP5b; urinary osteocalcin). Hazard ratios (HR) for any, major osteoporotic, vertebral and hip fractures were calculated as short (1, 2, 3 years) and long-term risk (5, 10, 15 years). Results: At 75 year, high CTX levels were associated with an increased risk of all fractures, including major osteoporotic fractures, across most time-frames (HRs ranging: 1.28 to 2.28). PINP was not consistently associated. Urinary osteocalcin was consistently associated with elevated short-term risk (HRs ranging: 1.83–2.72). Other BTMs were directionally in accordance, though not all statistically significant. BTMs were not predictive for hip fractures. Association of all BTMs attenuated over time; at 80 year none were associated with an increased fracture risk. Conclusion: CTX, urinary OC and TRAcP5b are predictive for fracture in a 1 to 3 year, perspective, whereas in the long-term or above age 80 years, BTMs appear less valuable. Resorption markers, particularly CTX, were more consistently associated with fracture risk than formation markers in the very elderly.
46.	Ivaska, K K, et al. (författare) For how many years can fracture be predicted by bone turnover markers: A 7.5-year follow-up study of 1040 elderly women (Abstracts of the 35th European Symposium on Calcified Tissues) 2008 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 82:Suppl. 1, s. 29-29 Konferensbidrag (refereegranskat)
47.	Johannesdottir, Fjola, et al. (författare) Mid-Thigh Cortical Bone Structural Parameters, Muscle Mass and Strength, and Association with Lower Limb Fractures in Older Men and Women (AGES-Reykjavik Study) 2012 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 90:5, s. 354-364 Tidskriftsartikel (refereegranskat)abstract In a cross-sectional study we investigated the relationship between muscle and bone parameters in the mid-thigh in older people using data from a single axial computed tomographic section through the mid-thigh. Additionally, we studied the association of these variables with incident low-trauma lower limb fractures. A total of 3,762 older individuals (1,838 men and 1,924 women), aged 66-96 years, participants in the AGES-Reykjavik study, were studied. The total cross-sectional muscular area and knee extensor strength declined with age similarly in both sexes. Muscle parameters correlated most strongly with cortical area and total shaft area (adjusted for age, height, and weight) but explained < 10 % of variability in those bone parameters. The increment in medullary area (MA) and buckling ratio (BR) with age was almost fourfold greater in women than men. The association between MA and muscle parameters was nonsignificant. During a median follow-up of 5.3 years, 113 women and 66 men sustained incident lower limb fractures. Small muscular area, low knee extensor strength, large MA, low cortical thickness, and high BR were significantly associated with fractures in both sexes. Our results show that bone and muscle loss proceed at different rates and with different gender patterns.
48.	Johansson, Peter, et al. (författare) Increased Risk of Hip Fracture in Patients with Lymphoma, a Swedish Population Study of 37,236 Lymphoma Patients. 2020 Ingår i: Calcified tissue international. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 106, s. 591-598 Tidskriftsartikel (refereegranskat)abstract Increased bone loss has been noted in lymphoma patients; however, the incidence of hip fracture is not known. The aim of our study was to explore the risk for hip fracture in patients with lymphoma compared with the entire Swedish population. The risk of hip fracture was determined in a retrospective population cohort study of adult Swedish lymphoma patients (n=37,236), diagnosed 1995-2015 and compared with the entire Swedish population during the same period. The incidence of hip fracture in lymphoma patients was higher in women than in men, increased by age, and decreased by calendar year as also demonstrated in the total population. 2.2% of the men and 4.7% of women with lymphoma sustained a hip fracture. For the total group of females, the hazard ratio (HR) was 1.19 (95% CI 1.11-1.28) and for men, the hazard ratio was 1.06 (95% CI 0.97-1.17) compared with the Swedish population. The HR for hip fracture (2016) was 2.80 (95% CI 1.20-6.53), 2.04 (95% CI 1.30-3.20), 1.56 (95% CI 1.21-2.01), 1.08 (95% CI 0.89-1.30), and 1.07 (95% CI 0.92-1.25) in females aged 40, 50, 60, 70, and 80years, respectively. Corresponding figures for men were not significant in 2016. Unmarried men with lymphoma had a two times higher risk for hip fracture (HR 2.02 95% CI 1.63-2.50) compared with married men. Patients with lymphoma had an increased risk of hip fracture, especially younger women and unmarried men. The incidence of hip fracture is decreased by calendar year in the lymphoma patients and the entire Swedish population.
49.	Kaastad, T S, et al. (författare) Effects of clodronate on cortical and trabecular bone in ovariectomized rats on a low calcium diet 1997 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 61:2, s. 158-164 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to evaluate the contribution of a low calcium diet to the cortical and trabecular osteoporosis seen in ovariectomized rats after 7 weeks on a low calcium diet and to investigate the effects of the bisphosphonate clodronate on this development of osteoporosis. Thirty-six mature, female Wistar rats were randomized into four groups: Ovx-B (bisphosphonate) and Ovx-C (control) were ovariectomized, and Sham-Ca (low calcium) and Sham+Ca (normal calcium) were sham operated. The first three groups were fed a low calcium diet (0.01%) and Sham+Ca normal rat chow (Ca 1.1%). The Ovx-B received 10 mg/kg s.c. clodronate daily for nine weeks, and Ovx-C, Sham-Ca, and Sham+Ca received the same volumes of saline. Bone mineral turnover measured as 85Sr-uptake was increased in all low calcium groups compared to Sham+Ca. The Sham+Ca femora had higher dry weight and ash weight than the other groups, and Ovx-C had higher dry weight compared with Ovx-B and Sham-Ca. Calcium content was lower in both Ovx groups compared to both Sham groups. Magnesium was lower in all groups compared to Sham+Ca and higher in Ovx-B compared with Ovx-C. In the femoral shaft, Sham+Ca had significantly higher ultimate bending moment, energy absorption, and deflection compared to the other three groups. Ultimate bending moment was higher in Sham-Ca than in Ovx-C. Stiffness was increased in both Sham+Ca and Ovx-B compared to Ovx-C. The maximum stress in the femoral midshaft was higher in Sham+Ca than in the other groups, and higher in Ovx-B than in Ovx-C. Histomorphometry showed increased medullary area in all low calcium groups compared to Sham+Ca and larger cortical area in Sham+Ca and Ovx-B compared to Ovx-C. Compared to Sham+Ca the trabecular bone volume was decreased to 30% in Sham-Ca and to 9% in Ovx-C, but was unchanged in Ovx-B. The low calcium diet generally increased bone mineral turnover and reduced the tibial bone volume. Femoral changes led to a reduction of cortical fracture strength and maximal stress. Ovariectomy in addition to a low calcium diet reduced femoral strength even more. Daily injections of clodronate to ovariectomized rats on a low calcium diet increased femoral shaft stiffness and maximum stress, and clodronate preserved both trabecular and cortical tibial bone volume completely.
50.	Kaastad, T S, et al. (författare) Vitamin D deficiency and ovariectomy reduced the strength of the femoral neck in rats 2001 Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 69:2, s. 102-108 Tidskriftsartikel (refereegranskat)abstract Vitamin D (vit D) deficiency is common in the elderly, and the aim of this study was to investigate whether vit D deprivation in ovariectomized (ovx) and normal rats would reduce fracture strength. Forty mature female Wistar rats were randomized into four groups: two were ovariectomized (ovx) and two were sham-operated (sham). One ovx and one sham group were fed a vit D-deficient diet (Ovx-D and Sham-D), and the control groups were fed normal rat chow (Ovx and Sham) for 12 weeks. Vit D deficiency was substantiated after 12 weeks by undetectable serum concentrations of 25OHD in the Sham-D and Ovx-D groups. 85Sr activity was lower in Sham-D than in the other groups (P < 0.005). Tibial and femoral weights and lengths showed no differences. Distal tibial trabecular bone volume was reduced in both ovx groups compare with sham (P < 0.005). Bone mineral density (BMD) was higher in sham than in Sham-D and both ovx groups (P < 0.005). Femoral area moment of inertia increased and ultimate stress decreased in Ovx-D compared with ovx (P < 0.05). Other biomechanical properties of the femoral shafts did not differ significantly. The femoral neck was significantly weaker in Ovx-D than in the other groups. In conclusion, ovx decreased tibial trabecular bone volume and both ovx and vit D depletion reduced femoral BMD in rats. Vit D depletion reduced the ultimate stress in the femoral shaft, and the combined depletion of estrogen and vit D significantly reduced the fracture strength in the femoral neck. This fits well with clinical evidence of how postmenopausal status combined with vit D deficiency lead to an increased risk of hip fractures, making this animal model a possible tool for investigating measures to prevent such fractures.

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