Skulan, J; DePaolo, D J
1999-11-23
Calcium from bone and shell is isotopically lighter than calcium of soft tissue from the same organism and isotopically lighter than source (dietary) calcium. When measured as the (44)Ca/(40)Ca isotopic ratio, the total range of variation observed is 5.5 per thousand, and as much as 4 per thousand variation is found in a single organism. The observed intraorganismal calcium isotopic variations and the isotopic differences between tissues and diet indicate that isotopic fractionation occurs mainly as a result of mineralization. Soft tissue calcium becomes heavier or lighter than source calcium during periods when there is net gain or loss of mineral mass, respectively. These results suggest that variations of natural calcium isotope ratios in tissues may be useful for assessing the calcium and mineral balance of organisms without introducing isotopic tracers.
Skulan, Joseph; DePaolo, Donald J.
1999-01-01
Calcium from bone and shell is isotopically lighter than calcium of soft tissue from the same organism and isotopically lighter than source (dietary) calcium. When measured as the 44Ca/40Ca isotopic ratio, the total range of variation observed is 5.5‰, and as much as 4‰ variation is found in a single organism. The observed intraorganismal calcium isotopic variations and the isotopic differences between tissues and diet indicate that isotopic fractionation occurs mainly as a result of mineralization. Soft tissue calcium becomes heavier or lighter than source calcium during periods when there is net gain or loss of mineral mass, respectively. These results suggest that variations of natural calcium isotope ratios in tissues may be useful for assessing the calcium and mineral balance of organisms without introducing isotopic tracers. PMID:10570137
The Role of Nutrition in the Changes in Bone and Calcium Metabolism During Space Flight
NASA Technical Reports Server (NTRS)
Morey-Holton, Emily R.; Arnaud, Sara B.
1995-01-01
On Earth, the primary purpose of the skeleton is provide structural support for the body. In space, the support function of the skeleton is reduced since, without gravity, structures have only mass and no weight. The adaptation to space flight is manifested by shifts in mineral distribution, altered bone turnover, and regional mineral deficits in weight-bearing bones. The shifts in mineral distribution appear to be related to the cephalic fluid shift. The redistribution of mineral from one bone to another or to and from areas in the same bone in response to alterations in gravitational loads is more likely to affect skeletal function than quantitative whole body losses and gains. The changes in bone turnover appear dependent upon changes in body weight with weight loss tending to increase bone resorption as well as decrease bone formation. During bedrest, the bone response to unloading varies depending upon the routine activity level of the subjects with more active subjects showing a greater suppression of bone formation in the iliac crest with inactivity. Changes in body composition during space flight are predicted by bedrest studies on Earth which show loss of lean body mass and increase tn body fat in adult males after one month. In ambulatory studies on Earth, exercising adult males of the same age, height, g weight, body mass index, and shoe size show significantly higher whole body mineral and lean body mass. than non-exercising subjects. Nutritional preference appears to change with activity level. Diet histories in exercisers and nonexercisers who maintain identical body weights show no differences in nutrients except for slightly higher carbohydrate intake in the exercisers. The absence of differences in dietary calcium in men with higher total body calcium is noteworthy. In this situation, the increased bone mineral content was facilitated by the calcium endocrine system. This regulatory system can be by-passed by raising dietary calcium. Increased calcium intake can increase the calcium content in normally loaded bone. However, bone with a higher calcium content still decreases proportionally to normal bone during unloading. Nutritional requirements in space should be reevaluated with respect to these adaptive changes to loading and physical activity.
Motil, Kathleen J; Barrish, Judy O; Neul, Jeffrey L; Glaze, Daniel G
2014-09-01
The aim of the present study was to characterize biomarkers of bone turnover and their relation with bone mineral mass in a cross-sectional cohort of girls with Rett syndrome (RTT) and to examine the role of dietary, biochemical, hormonal, and inflammatory factors on bone mineral mass and bone biomarkers in this disorder. Total body bone mineral content (BMC) and bone mineral density (BMD) were determined by dual-energy x-ray absorptiometry. Dietary nutrient intakes were determined from 3-day food records. Biomarkers of bone turnover, bone metabolites, vitamin D metabolites, hormones, and inflammatory markers were measured by standard clinical laboratory methods. Serum osteocalcin, bone alkaline phosphatase, and C-telopeptide showed significant inverse relations with age in the RTT cohort. Mean osteocalcin concentrations were significantly lower and mean bone alkaline phosphatase concentrations were significantly higher for individual age groups in the RTT cohort than mean values for their respective age ranges in the reference population. Significant inverse associations were identified between urinary calcium losses, expressed as calcium:creatinine ratios, and total body BMC and BMD z scores. Dietary protein, calcium, and phosphorus intakes, expressed as a proportion of Dietary Reference Intakes for age and sex, showed significant positive associations with total body BMD z scores. The present study suggests decreased bone formation instead of increased bone resorption may explain in part the deficits in bone mineral mass in RTT and that attention to the adequacy of dietary protein, calcium, and phosphorus intakes may offer an opportunity to improve bone health in RTT.
Burrows, Melonie; Baxter-Jones, Adam; Mirwald, Robert; Macdonald, Heather; McKay, Heather
2009-05-01
We investigated the contribution of ethnicity, physical activity, body composition, and calcium intake to bone accrual across 7 years of growth. We assessed 80 Caucasian and 74 Asian boys and 81 Caucasian and 64 Asian girls at baseline and retained 155 children across all 7 years. Ethnicity, physical activity, and calcium intake were assessed by questionnaire; fat mass, lean mass, and bone mineral content (BMC) of the whole body (WB), lumbar spine (LS), total proximal femur (PF(TOT)), and femoral neck (FN) were measured using DXA (Hologic QDR 4500). We aligned children on peak height velocity and utilized multilevel modeling to assess bone mineral accrual. Height and lean mass accounted for 51.8% and 44.1% of BMC accrual in children. There was a significant difference in physical activity, calcium intake, and lean mass between Asians and Caucasian boys and girls at baseline and conclusion (p < 0.05). In boys, physical activity and ethnicity significantly predicted BMC accrual at the FN. In girls, Asians had significantly lower PF(TOT) and FN BMC. Calcium was a significant predictor of WB BMC accrual in boys and girls. In conclusion, our findings highlight the importance of accounting for ethnicity in pediatric studies. Physical activity, dietary calcium, and lean mass positively influence bone accrual and are lower in Asian compared to Caucasian children from a very young age.
Lieben, L; Stockmans, I; Moermans, K; Carmeliet, G
2013-11-01
Pregnancy challenges maternal calcium handling because sufficient calcium has to be transferred to the fetus to ensure fetal bone mass acquisition. 1,25(OH)2 vitamin D [1,25(OH)2D] is an important regulator of calcium homeostasis during adulthood, yet its role seems redundant for the maternal adaptations to pregnancy as well as during fetal development. However, not only deficiency but also excess of 1,25(OH)2D can be harmful and we therefore questioned whether high maternal 1,25(OH)2D levels may injure fetal development or neonatal outcome, as maternal-fetal transport of 1,25(OH)2D has been largely disputed. To this end, vitamin D receptor (VDR) null (Vdr(-/-)) females, displaying high 1,25(OH)2D levels, were mated with Vdr(+/-) males to obtain pregnancies with fetuses that are responsive (Vdr(+/-)) or resistant (Vdr(-/-)) to 1,25(OH)2D. Surprisingly, most of the Vdr(+/-) neonates died shortly after birth, whereas none of the Vdr(-/-). Mechanistically, we noticed that in Vdr(+/-) embryos, serum calcium levels were normal, but that skeletal calcium storage was reduced as evidenced by decreased mineralized bone mass as well as bone mineral content. More precisely, bone formation was decreased and the level of bone mineralization inhibitors was increased. This decreased fetal skeletal calcium storage may severely compromise calcium balance and survival at birth. In conclusion, these data indicate that high maternal 1,25(OH)2D levels are transferred across the placental barrier and adversely affect the total amount of calcium stored in fetal bones which is accompanied by neonatal death. © 2013 Elsevier Inc. All rights reserved.
Bone mineralization in childhood and adolescence.
Bachrach, L K
1993-08-01
Prevention of osteoporosis depends on establishing adequate peak bone mass in the first two decades of life. Achievement of this goal requires an understanding of factors that promote skeletal health. Genetic factors are important determinants of adult bone mass, but nonheritable variables, including body mass, calcium nutriture, sex steroids, and activity can strongly influence whether maximal bone mineral is achieved. Acquisition of bone mineral continues throughout childhood and adolescence, reaching a lifetime maximum in early adulthood. Adolescence is a particularly critical time for bone mineral accretion as more than half of the bone calcium is normally laid down during the teen years. Chronic illness, malnutrition, or endocrine deficiencies at this age may result in profound deficits in bone mass, which may not be fully reversible. These risk factors contribute to the osteopenia associated with anorexia nervosa, exercise-induced amenorrhea, delayed puberty, Turner's syndrome, and growth hormone deficiency.
Srinivasan, Kritika; Naula, Diana P.; Mijares, Dindo Q.; Janal, Malvin N.; LeGeros, Raquel Z.; Zhang, Yu
2016-01-01
Calcium and other trace mineral supplements have previously demonstrated to safely improve bone quality. We hypothesize that our novel calcium-phosphate based biomaterial (SBM) preserves and promotes mandibular bone formation in male and female rats on mineral deficient diet (MD). Sixty Sprague-Dawley rats were randomly assigned to receive one of three diets (n = 10): basic diet (BD), MD or mineral deficient diet with 2% SBM. Rats were sacrificed after 6 months. Micro-Computed Tomography (μCT) was used to evaluate bone volume and 3D-microarchitecture while microradiography (Faxitron) was used to measure bone mineral density from different sections of the mandible. Results showed that bone quality varied with region, gender and diet. MD reduced bone mineral density (BMD) and volume and increased porosity. SBM preserved BMD and bone mineral content (BMC) in the alveolar bone and condyle in both genders. In the alveolar crest and mandibular body, while preserving more bone in males, SBM also significantly supplemented female bone. Results indicate that mineral deficiency leads to low bone mass in skeletally immature rats, comparatively more in males. Furthermore, SBM administered as a dietary supplement was effective in preventing mandibular bone loss in all subjects. This study suggests that the SBM preparation has potential use in minimizing low peak bone mass induced by mineral deficiency and related bone loss irrespective of gender. PMID:26914814
Motil, Kathleen J.; Barrish, Judy O.; Neul, Jeffrey L.; Glaze, Daniel G.
2014-01-01
Objective To characterize biomarkers of bone turnover and their relation with bone mineral mass in a cross-sectional cohort of females with Rett syndrome (RTT) and to examine the role of dietary, biochemical, hormonal, and inflammatory factors on bone mineral mass and bone biomarkers in this disorder. Methods Total body bone mineral content (BMC) and density (BMD) were determined by dual-energy x-ray absorptiometry. Dietary nutrient intakes were determined from 3-day food records. Biomarkers of bone turnover, bone metabolites, vitamin D metabolites, hormones, and inflammatory markers were measured by standard clinical laboratory methods. Results Serum osteocalcin, bone alkaline phosphatase, and C-telopeptide showed significant inverse relations with age in the RTT cohort. Mean osteocalcin concentrations were significantly lower and mean bone alkaline phosphatase concentrations were significantly higher for individual age groups in the RTT cohort than mean values for their respective age ranges in the reference population. Significant inverse associations were identified between urinary calcium losses, expressed as calcium:creatinine ratios, and total body BMC and BMD z-scores. Dietary protein, calcium, and phosphorus intakes, expressed as a proportion of Dietary Reference Intakes for age and gender, showed significant positive associations with total body BMD z-scores. Conclusion This study suggests decreased bone formation rather than increased bone resorption may explain in part the deficits in bone mineral mass in RTT and that attention to the adequacy of dietary protein, calcium and phosphorus intakes may offer an opportunity to improve bone health in RTT. PMID:25144778
Hake fish bone as a calcium source for efficient bone mineralization.
Flammini, Lisa; Martuzzi, Francesca; Vivo, Valentina; Ghirri, Alessia; Salomi, Enrico; Bignetti, Enrico; Barocelli, Elisabetta
2016-01-01
Calcium is recognized as an essential nutritional factor for bone health. An adequate intake is important to achieve or maintain optimal bone mass in particular during growth and old age. The aim of the present study was to evaluate the efficiency of hake fish bone (HBF) as a calcium source for bone mineralization: in vitro on osteosarcoma SaOS-2 cells, cultured in Ca-free osteogenic medium (OM) and in vivo on young growing rats fed a low-calcium diet. Lithotame (L), a Ca supplement derived from Lithothamnium calcareum, was used as control. In vitro experiments showed that HBF supplementation provided bone mineralization similar to standard OM, whereas L supplementation showed lower activity. In vivo low-Ca HBF-added and L-added diet similarly affected bone deposition. Physico-chemical parameters concerning bone mineralization, such as femur breaking force, tibia density and calcium/phosphorus mineral content, had beneficial effects from both Ca supplementations, in the absence of any evident adverse effect. We conclude HBF derived from by-product from the fish industry is a good calcium supplier with comparable efficacy to L.
Lappe, Joan M; Watson, Patrice; Gilsanz, Vicente; Hangartner, Thomas; Kalkwarf, Heidi J; Oberfield, Sharon; Shepherd, John; Winer, Karen K; Zemel, Babette
2015-01-01
Childhood and adolescence are critical periods of bone mineral content (BMC) accrual that may have long-term consequences for osteoporosis in adulthood. Adequate dietary calcium intake and weight-bearing physical activity are important for maximizing BMC accrual. However, the relative effects of physical activity and dietary calcium on BMC accrual throughout the continuum of pubertal development in childhood remains unclear. The purpose of this study was to determine the effects of self-reported dietary calcium intake and weight-bearing physical activity on bone mass accrual across the five stages of pubertal development in a large, diverse cohort of US children and adolescents. The Bone Mineral Density in Childhood study was a mixed longitudinal study with 7393 observations on 1743 subjects. Annually, we measured BMC by dual-energy X-ray absorptiometry (DXA), physical activity and calcium intake by questionnaire, and pubertal development (Tanner stage) by examination for up to 7 years. Mixed-effects regression models were used to assess physical activity and calcium intake effects on BMC accrual at each Tanner stage. We found that self-reported weight-bearing physical activity contributed to significantly greater BMC accrual in both sexes and racial subgroups (black and nonblack). In nonblack males, the magnitude of the activity effect on total body BMC accrual varied among Tanner stages after adjustment for calcium intake; the greatest difference between high- and low-activity boys was in Tanner stage 3. Calcium intake had a significant effect on bone accrual only in nonblack girls. This effect was not significantly different among Tanner stages. Our findings do not support differential effects of physical activity or calcium intake on bone mass accrual according to maturational stage. The study demonstrated significant longitudinal effects of weight-bearing physical activity on bone mass accrual through all stages of pubertal development. © 2014 American Society for Bone and Mineral Research.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zanzi, I; Colbert, C; Bachtell, R
1978-01-01
Two groups of investigators utilized three techniques for evaluating bone mineral mass. In one institution, total-body calcium by total body neutron activation analysis, and bone mineral content of the radius by photon absorptiometry were measured concomitantly. In the other institution, the mean bone mineral content of the three inner phalanges of the left hand was measured by radiographic absorptiometry. These techniques were applied to two groups of subjects: 16 patients with primary osteoporosis and 14 healthy marathon runners. The higher correlation found in osteoporotic patients may be related to the diffuse nature of this condition and to differences in themore » distribution of skeletal mass in the marathon runners.« less
Lieben, Liesbet; Masuyama, Ritsuko; Torrekens, Sophie; Van Looveren, Riet; Schrooten, Jan; Baatsen, Pieter; Lafage-Proust, Marie-Hélène; Dresselaers, Tom; Feng, Jian Q.; Bonewald, Lynda F.; Meyer, Mark B.; Pike, J. Wesley; Bouillon, Roger; Carmeliet, Geert
2012-01-01
Serum calcium levels are tightly controlled by an integrated hormone-controlled system that involves active vitamin D [1,25(OH)2D], which can elicit calcium mobilization from bone when intestinal calcium absorption is decreased. The skeletal adaptations, however, are still poorly characterized. To gain insight into these issues, we analyzed the consequences of specific vitamin D receptor (Vdr) inactivation in the intestine and in mature osteoblasts on calcium and bone homeostasis. We report here that decreased intestinal calcium absorption in intestine-specific Vdr knockout mice resulted in severely reduced skeletal calcium levels so as to ensure normal levels of calcium in the serum. Furthermore, increased 1,25(OH)2D levels not only stimulated bone turnover, leading to osteopenia, but also suppressed bone matrix mineralization. This resulted in extensive hyperosteoidosis, also surrounding the osteocytes, and hypomineralization of the entire bone cortex, which may have contributed to the increase in bone fractures. Mechanistically, osteoblastic VDR signaling suppressed calcium incorporation in bone by directly stimulating the transcription of genes encoding mineralization inhibitors. Ablation of skeletal Vdr signaling precluded this calcium transfer from bone to serum, leading to better preservation of bone mass and mineralization. These findings indicate that in mice, maintaining normocalcemia has priority over skeletal integrity, and that to minimize skeletal calcium storage, 1,25(OH)2D not only increases calcium release from bone, but also inhibits calcium incorporation in bone. PMID:22523068
USDA-ARS?s Scientific Manuscript database
Calcium absorption efficiency and bone mineral mass are increased in adolescents who regularly consume inulin-type fructans (ITF). The mechanism of action in increasing absorption is unknown but may be related to increased colonic calcium absorption. We conducted a study in young adults designed to ...
French, Simone A; Story, Mary; Fulkerson, Jayne A; Himes, John H; Hannan, Peter; Neumark-Sztainer, Dianne; Ensrud, Kristine
2005-01-01
Background A two-year, community-based, group-randomized trial to promote bone mass gains among 9–11 year-old girls through increased intake of calcium-rich foods and weight-bearing physical activity was evaluated. Methods Following baseline data collection, 30 5th-grade Girl Scout troops were randomized to a two-year behavioral intervention program or to a no-treatment control group. Evaluations were conducted at baseline, one year, and two years. Measures included bone mineral content, density, and area (measured by DXA), dietary calcium intake (24-hour recall), and weight-bearing physical activity (physical activity checklist interview). Mixed-model regression was used to evaluate treatment-related changes in bone mineral content (g) for the total body, lumbar spine (L1-L4), proximal femur, one-third distal radius, and femoral neck. Changes in eating and physical activity behavioral outcomes were examined. Results Although the intervention was implemented with high fidelity, no significant intervention effects were observed for total bone mineral content or any specific bone sites. Significant intervention effects were observed for increases in dietary calcium. No significant intervention effects were observed for increases in weight-bearing physical activity. Conclusion Future research needs to identify the optimal dosage of weight-bearing physical activity and calcium-rich dietary behavior change required to maximize bone mass gains in pre-adolescent and adolescent girls. PMID:16029507
Implications of sodium mass balance for interpreting the calcium cycle of a forested ecosystem
Scott W. Bailey; Donald C. Buso; Gene E. Likens
2003-01-01
Disturbance of forest ecosystems, such as that caused by harvesting or acid deposition, is thought to alter the ability of the ecosystem to retain nutrients. Although many watershed studies have suggested depletion of available calcium (Ca) pools, interpretation of ecosystem Ca mass balance has been limited by the difficulty in obtaining mineral weathering flux...
Veganism, bone mineral density, and body composition: a study in Buddhist nuns.
Ho-Pham, L T; Nguyen, P L T; Le, T T T; Doan, T A T; Tran, N T; Le, T A; Nguyen, T V
2009-12-01
This cross-sectional study showed that, although vegans had lower dietary calcium and protein intakes than omnivores, veganism did not have adverse effect on bone mineral density and did not alter body composition. Whether a lifelong vegetarian diet has any negative effect on bone health is a contentious issue. We undertook this study to examine the association between lifelong vegetarian diet and bone mineral density and body composition in a group of postmenopausal women. One hundred and five Mahayana Buddhist nuns and 105 omnivorous women (average age = 62, range = 50-85) were randomly sampled from monasteries in Ho Chi Minh City and invited to participate in the study. By religious rule, the nuns do not eat meat or seafood (i.e., vegans). Bone mineral density (BMD) at the lumbar spine (LS), femoral neck (FN), and whole body (WB) was measured by DXA (Hologic QDR 4500). Lean mass, fat mass, and percent fat mass were also obtained from the DXA whole body scan. Dietary calcium and protein intakes were estimated from a validated food frequency questionnaire. There was no significant difference between vegans and omnivores in LSBMD (0.74 +/- 0.14 vs. 0.77 +/- 0.14 g/cm(2); mean +/- SD; P = 0.18), FNBMD (0.62 +/- 0.11 vs. 0.63 +/- 0.11 g/cm(2); P = 0.35), WBBMD (0.88 +/- 0.11 vs. 0.90 +/- 0.12 g/cm(2); P = 0.31), lean mass (32 +/- 5 vs. 33 +/- 4 kg; P = 0.47), and fat mass (19 +/- 5 vs. 19 +/- 5 kg; P = 0.77) either before or after adjusting for age. The prevalence of osteoporosis (T scores < or = -2.5) at the femoral neck in vegans and omnivores was 17.1% and 14.3% (P = 0.57), respectively. The median intake of dietary calcium was lower in vegans compared to omnivores (330 +/- 205 vs. 682 +/- 417 mg/day, P < 0.001); however, there was no significant correlation between dietary calcium and BMD. Further analysis suggested that whole body BMD, but not lumbar spine or femoral neck BMD, was positively correlated with the ratio of animal protein to vegetable protein. These results suggest that, although vegans have much lower intakes of dietary calcium and protein than omnivores, veganism does not have adverse effect on bone mineral density and does not alter body composition.
Calcium requirements for Asian children and adolescents.
Lee, Warren Tak Keung; Jiang, Ji
2008-01-01
Calcium is important for bone health. Over the last 15 years, reference calcium intakes in Western countries have been revised upwards for maximizing bone mass at skeletal maturity and for prevention of osteoporotic fractures. Some of these reference figures have also been adopted for use in Asian countries. However, the scientific data based on for revising reference calcium intakes in the West was largely based on Caucasians. Limited human studies relating to calcium requirements and bone mineralization have been conducted in Asians in Asia. In children and adolescents, a trial has confirmed no effects of calcium supplementation on bone gains in adolescent girls after 7 years. A meta-analysis has also revealed that calcium supplementation has little beneficial effects on bone gain. Given that genetic factors, hormonal status, body size, bone structure, diets, physical activity, vitamin D status and adaptation could modify calcium retention and bone integrity, these factors need to be considered collectively to promote bone health in Asian populations. Furthermore, studies to identify indigenous foods rich in calcium and high in bioavailability are needed to widen sources of dietary calcium. Ethnic differences in calcium retention, hormonal status, bone structure, bone mineral accretion and peak bone mass are evident among Asians, Caucasians and Blacks in USA. Hence, reference calcium intakes for Asians are likely to be unique and different from those of Caucasians. More research has to be conducted in Asian populations in order to develop appropriate reference calcium intakes for the region.
Cole, T. J.; Laskey, M. A.; Ceesay, M.; Mendy, M. B.; Sawo, Y.; Prentice, A.
2014-01-01
Context: Calcium intake during growth is essential for future bone health but varies widely between individuals and populations. The impact on bone of increasing calcium intake is unknown in a population where low calcium intake, stunting, and delayed puberty are common. Objective: To determine the effect of prepubertal calcium supplementation on mean age at peak velocity for bone growth and mineral accrual. Design and Setting: Prospective follow-up of boys in rural Gambia, West Africa, who had participated in a double-blind, randomized, placebo-controlled trial of calcium supplementation. Participants: Eighty boys, initially aged 8.0–11.9 years, were followed up for 12 years. Interventions: Subjects received 1 year of calcium carbonate supplementation (1000 mg daily, 5 d/wk). Main Outcome Measures: Dual-energy x-ray absorptiometry measurements were carried out for whole body (WB), lumbar spine, and total hip bone mineral content, bone area (BA), and WB lean mass. Super imposition by translation and rotation models was made to assess bone growth. Results: Age at peak velocity was consistently earlier in the calcium group compared to the placebo group, for WB bone mineral content (mean, −6.2 [SE, 3.1]; P = .05), WB BA (mean, −7.0 [SE, 3.2] mo; P = .03), lumbar spine and total hip BA. By young adulthood, supplementation did not change the amount of bone accrued (mineral or size) or the rate of bone growth. Conclusions: Twelve months of prepubertal calcium carbonate supplementation in boys with a low calcium diet advanced the adolescent growth spurt but had no lasting effect on bone mineral or bone size. There is a need for caution when applying international recommendations to different populations. PMID:24762110
[High prevalence of osteoporosis in asymptomatic postmenopausal Mapuche women].
Ponce, Lucía; Larenas, Gladys; Riedemann, Pablo
2002-12-01
Genetic and environmental factors are responsible for variations in the frequency of osteoporosis. Prevalence of osteoporosis in Mapuche women (native Chileans) is unknown. To assess the prevalence and risk factors for osteoporosis in Mapuche women. A random sample of 95 asymptomatic postmenopausal Mapuche females, stratified by age, was studied. Women with diseases or medications that could interfere with calcium metabolism were excluded. Spine and femoral neck bone mass density was determined using a Lunar DPX Alpha densitometer. Seventeen percent of women had normal bone mineral density in both spine and femoral neck. In the spine, 25.3% had a normal bone mineral density, 17.9% had osteopenia and 56.8% had osteoporosis. In the femoral neck, 34.7% had a normal bone mineral density, 57.9% had osteopenia, and 7.4% had osteoporosis. There was a positive correlation between bone mineral density and body mass index. Women with more than one hour per day of physical activity, had a significantly lower proportion of osteopenia or osteoporosis. No association between bone mineral density and parity or calcium intake, was observed. There is a high prevalence of osteopenia and osteoporosis among Mapuche women. Osteoporosis was associated with low body mass index.
Calcium Kinetics During Space Flight
NASA Technical Reports Server (NTRS)
Smith, Scott M.; Wastney, Meryl E.; OBrien, Kimberly O.; Lane, Helen W.
1999-01-01
Bone loss is one of the most detrimental effects of space flight, threatening to limit the duration of human space missions. The ability to understand and counteract this loss will be critical for crew health and safety during and after extended-duration missions. The hypotheses to be tested in this project are that space flight alters calcium homeostasis and bone mineral metabolism, and that calcium homeostasis and bone mineral metabolism will return to baseline within days to weeks of return to Earth. These hypotheses will be evidenced by elevated rates of bone mineral resorption and decreased bone mineral deposition, decreased absorption of dietary calcium, altered calcitropic endocrine profiles, elevated excretion of calcium in urine and feces, and elevated excretion of markers of bone resorption. The second hypothesis will be evidenced by return of indices of calcium homeostasis and bone metabolism to preflight levels within days to weeks of return to Earth. Studies will be conducted on International Space Station astronauts before, during, and after extended-duration flights. Measurements of calcium kinetics, bone mass, and endocrine/biochemical markers of bone and calcium homeostasis will be conducted. Kinetic studies utilizing dual isotope tracer kinetic studies and mathematical modeling techniques will allow for determination of bone calcium deposition, bone calcium resorption, dietary calcium absorption and calcium excretion (both urinary and endogenous fecal excretion). These studies will build upon preliminary work conducted on the Russian Mir space station. The results from this project will be critical for clarifying how microgravity affects bone and calcium homeostasis, and will provide an important control point for assessment of countermeasure efficacy. These results are expected to aid in developing countermeasures for bone loss, both for space crews and for individuals on Earth who have metabolic bone diseases.
Lifetime physical activity and calcium intake related to bone density in young women.
Wallace, Lorraine Silver; Ballard, Joyce E
2002-05-01
Osteoporosis is a significant public health problem associated with increased mortality and morbidity. Our aim in this cross-sectional study was to investigate the relationship between lifetime physical activity and calcium intake and bone mineral density (BMD) and BMC (bone mineral content) in 42 regularly menstruating Caucasian women (age 21.26+/-1.91 years, BMI 23.83+/-5.85). BMD and BMC at the lumbar spine (L2-L4), hip (femoral neck, trochanter, total), and total body were assessed by dual energy x-ray absorptiometry (DXA). Lifetime history of physical activity and calcium intake was obtained by a structured interview using valid and reliable instruments. Measures of both lifetime physical activity and calcium intake were highly correlated. In stepwise multiple regression analyses, lean mass was the most important and consistent factor for predicting BMD and BMC at all skeletal sites (attributable r2 = 28.8%-78.7%). Lifetime physical activity contributed to 3.0% of the variation in total body BMD, and life-time weight-bearing physical activity explained 15.1% of variance in lumbar spine BMC. Current calcium intake predicted 6% of the variance in BMD at the femoral neck and trochanter. We found lean mass to be a powerful predictor of BMD and BMC in young women. Because lean mass can be modified to some extent by physical activity, public health efforts must be directed at increasing physical activity throughout the lifespan. Furthermore, our results suggest that adequate calcium intake may help to enhance bone mass, thus decreasing the risk of osteoporotic fracture later in life.
Prebiotics and the absorption of minerals: a review of experimental and human data
USDA-ARS?s Scientific Manuscript database
Dietary factors, including calcium and vitamin D intake, absorption, and status, lifestyle factors including physical activity, and genetics interact to determine peak bone mass. The current recommended dietary intake of calcium (adequate intake, AI) of 1300 mg/day in the United States for adolescen...
NASA Astrophysics Data System (ADS)
Blättler, Clara L.; Higgins, John A.
2017-12-01
Carbonate minerals constitute a major component of the sedimentary geological record and an archive of a fraction of the carbon and calcium cycled through the Earth's surface reservoirs for over three billion years. For calcium, carbonate minerals constitute the ultimate sink for almost all calcium liberated during continental and submarine weathering of silicate minerals. This study presents >500 stable isotope ratios of calcium in Precambrian carbonate sediments, both limestones and dolomites, in an attempt to characterize the isotope mass balance of the sedimentary carbonate reservoir through time. The mean of the dataset is indistinguishable from estimates of the calcium isotope ratio of bulk silicate Earth, consistent with the Urey cycle being the dominant mechanism exchanging calcium among surface reservoirs. The variability in bulk sediment calcium isotope ratios within each geological unit does not reflect changes in the global calcium cycle, but rather highlights the importance of local mineralogical and/or diagenetic effects in the carbonate record. This dataset demonstrates the potential for calcium isotope ratios to help assess these local effects, such as the former presence of aragonite, even in rocks with a history of neomorphism and recrystallization. Additionally, 29 calcium isotope measurements are presented from ODP (Ocean Drilling Program) Site 801 that contribute to the characterization of altered oceanic crust as an additional sink for calcium, and whose distinct isotopic signature places a limit on the importance of this subduction flux over Earth history.
Costi, D; Calcaterra, P G; Iori, N; Vourna, S; Nappi, G; Passeri, M
1999-12-01
The aim of this research was to establish the importance of calcium intake through mineral water on vertebral bone density in women. To this purpose, we examined 255 women divided into two groups: those regularly drinking a high calcium content mineral water (group A; no.=175) and those using different type of water with a lower calcium content (group B; no.=80). Their dietary daily calcium intake was determined by means of a validated questionnaire (N.I.H. Consensus statement) and vertebral bone density was measured by Dual-Energy X-ray absorptiometry (Unigamma-plus ACN densitometer). Women in group A ingested a significantly higher quantity of calcium in water than women in group B (mean difference 258 mg; 95% confidence limits: 147-370 mg). The average bone density values were slightly but significantly higher in group A as compared to group B (mean+/-SD: 1.044+0,15 vs 1.002+0,14; p=0.03). In addition to age, BMI and menopausal status, calcium intake was a significant predictor of spinal BMD. These 4 variables explained about 35% of the spinal BMD variance. When the analysis was repeated separately for pre- and post-menopausal subjects, calcium remained a significant predictor in post-menopausal women (t=2.28; p=0.02), but not in premenopausal women. These results underline the importance of a lifelong daily calcium intake, resulting by the regular drinking of high bioavailable calcium water, in order to maintain bone mass after the menopause, in comparison to the use of a lower content calcium water.
Ramprasath, Vanu Ramkumar; Jones, Peter J H
2016-01-01
The objective was to determine safety and efficacy of health supplements "Beyond Tangy Tangerine," a multivitamin/mineral complex and combination of multivitamin/mineral complex, "Osteofx," a bone healthy supplement and "Ultimate Essential Fatty Acids" in Sprague Dawley rats consuming high-fat diets. Initially a pilot study was conducted which confirmed palatability and acceptability of supplements. In a second study, rats (n = 15/group) were randomized to Control; Multivitamin/mineral complex (2 g/kg BW) or Combination (2 g Multivitamin/mineral complex, 1.5 g Bone healthy supplement and 0.34 g Essential fatty acids/kg BW). No differences were observed in BW change, feed intake, organ weights or bone mineral composition with supplementations compared to control. Multivitamin/mineral complex supplementation decreased abdominal white adipose tissue weights (WAT) (p = .005), total (p = .033) and fat mass (p = .040), plasma IL-6 (p = .016) and ALKP (p = .038) and elevated plasma calcium (p < .001), phosphorus (p = .038), total protein (p = .002), albumin (p = .014) and globulin (p = .018), compared to control. Similarly, combination supplementation reduced WAT (p < .001), total (p = .023) and fat mass (p = .045), plasma triglycerides (p = .018), IL-6 (p = .002) and ALKP (p < .001) with increases in plasma calcium (p = .031), phosphorus (p < .001) compared to control. Results indicate that consuming either supplement can be considered safe and improves overall health by reducing inflammation, abdominal fat mass and plasma triglycerides, as well as promote bone health.
Weber, D R; Stark, L J; Ittenbach, R F; Stallings, V A; Zemel, B S
2017-06-01
Many children do not consume the recommended daily allowance of calcium. Inadequate calcium intake in childhood may limit bone accrual. The objective of this study was to determine if a behavioral modification and nutritional education (BM-NE) intervention improved dietary calcium intake and bone accrual in children. 139 (86 female) healthy children, 7-10 years of age, were enrolled in this randomized controlled trial conducted over 36 months. Participants randomized to the BM-NE intervention attended five sessions over a 6-week period designed to increase calcium intake to 1500 mg/day. Participants randomized to the usual care (UC) group received a single nutritional counseling session. The Calcium Counts Food Frequency Questionnaire was used to assess calcium intake; dual energy X-ray absorptiometry was used to assess areal bone mineral density (aBMD) and bone mineral content (BMC). Longitudinal mixed effects models were used to assess for an effect of the intervention on calcium intake, BMC and aBMD. BM-NE participants had greater increases in calcium intake that persisted for 12 months following the intervention compared with UC. The intervention had no effect on BMC or aBMD accrual. Secondary analyses found a negative association between calcium intake and adiposity such that greater calcium intake was associated with lesser gains in body mass index and fat mass index. A family-centered BM-NE intervention program in healthy children was successful in increasing calcium intake for up to 12 months but had no effect on bone accrual. A beneficial relationship between calcium intake and adiposity was observed and warrants future study.
Bone mineral density, serum albumin and serum magnesium.
Saito, Noboru; Tabata, Naoto; Saito, Saburou; Andou, Yoshihisa; Onaga, Yukiko; Iwamitsu, Akihiro; Sakamoto, Morihide; Hori, Tuyoshi; Sayama, Harumi; Kawakita, Toshiko
2004-12-01
This study explores clinical and laboratory abnormalities that contribute to the prevalence of bone fractures in frail and control elderly patients, to ascertain factors that relate to bone strength and fragility. Patients were selected as free from renal failure and not taking supplements or medications that affect their magnesium status, and categorized according to their underlying diseases, sex and age, and evaluated by tests of bone strength. Findings, differentiating elderly patients on the basis of their magnesium, calcium, serum albumin, body mass, bone mineral density and their fracture occurrence were tabulated. Evidence is presented of low magnesium and albumin serum levels, especially in women with low bone density, as well as of low calcium and trace minerals.
Haffner-Luntzer, Melanie; Heilmann, Aline; Heidler, Verena; Liedert, Astrid; Schinke, Thorsten; Amling, Michael; Yorgan, Timur Alexander; Vom Scheidt, Annika; Ignatius, Anita
2016-11-01
Efficient calcium absorption is essential for skeletal health. Patients with impaired gastric acidification display low bone mass and increased fracture risk because calcium absorption is dependent on gastric pH. We investigated fracture healing and post-traumatic bone turnover in mice deficient in Cckbr, encoding a gastrin receptor that affects acid secretion by parietal cells. Cckbr-/- mice display hypochlorhydria, calcium malabsorption, and osteopenia. Cckbr-/- and wildtype (WT) mice received a femur osteotomy and were fed either a standard or calcium-enriched diet. Healed and intact bones were assessed by biomechanical testing, histomorphometry, micro-computed tomography, and quantitative backscattering. Parathyroid hormone (PTH) serum levels were determined by enzyme-linked immunosorbent assay. Fracture healing was unaffected in Cckbr-/- mice. However, Cckbr-/- mice displayed increased calcium mobilization from the intact skeleton during bone healing, confirmed by significantly elevated PTH levels and osteoclast numbers compared to WT mice. Calcium supplementation significantly reduced secondary hyperparathyroidism and bone resorption in the intact skeleton in both genotypes, but more efficiently in WT mice. Furthermore, calcium administration improved bone healing in WT mice, indicated by significantly increased mechanical properties and bone mineral density of the fracture callus, whereas it had no significant effect in Cckbr-/- mice. Therefore, under conditions of hypochlorhydria-induced calcium malabsorption, calcium, which is essential for callus mineralization, appears to be increasingly mobilized from the intact skeleton in favor of fracture healing. Calcium supplementation during fracture healing prevented systemic calcium mobilization, thereby maintaining bone mass and improving fracture healing in healthy individuals whereas the effect was limited by gastric hypochlorhydria. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1914-1921, 2016. © 2016 The Authors. Journal of Orthopaedic Research Published by by Wiley Periodicals, Inc.
Bordbar, Mohammad Reza; Haghpanah, Sezaneh; Dabbaghmanesh, Mohammad Hossein; Omrani, Gholamhossein Ranjbar; Saki, Forough
2016-12-01
Acute leukemia is the most common malignancy in children. We showed that low bone mass is prevalent among children with leukemia, especially in femur. Serum calcium, exercise, chemotherapy protocol, and radiotherapy are the main contributing factors. We suggest that early diagnosis and treatment of this problem could improve bone health in them. Acute leukemia is the most common malignancy in children and has been reported to be associated with low bone mass. Due to lack of sufficient data about the bone mineral density of children with leukemia in the Middle East, and inconsistencies between possible associated factors contributing to decreasing bone density in these children, we aimed to conduct a case-control study in Iran. This case-control study was conducted on 60 children with acute leukemia and 60 age- and sex-matched healthy controls. Anthropometric data, sun exposure, puberty, physical activity, and mineral biochemical parameters were assessed. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DEXA). Data analysis was done by SPSS software v. 21. Serum calcium was higher in the control group (P = 0.012) while serum phosphorous, alkaline phosphatase, and serum 25(OH)D 3 were higher in children with leukemia with P values of 0.04, 0.002, and 0.036, respectively. Sun exposure and physical activity were more in healthy controls (P values <0.001 and 0.003, respectively). Prevalence of vitamin D deficiency in case and control groups was 57.8 and 79.4 %, respectively. This prevalence was higher in healthy controls (P value = 0.007). Both lumbar and femoral neck bone mineral apparent density (BMAD) were higher in the control group (P value <0.001). Serum calcium, physical activity, and radiotherapy were the most relevant factors associated with lumbar BMAD. Femoral neck BMAD was associated with chemotherapy protocol. Low bone mass for chronological age is prevalent among children with leukemia, especially in the femoral neck. Serum calcium, physical activity, chemotherapy protocol, and radiotherapy are the main contributing factors.
Courteix, D; Jaffré, C; Lespessailles, E; Benhamou, L
2005-06-01
High calcium intake combined with physical activity during childhood have been shown to improve bone mass accrual and bone mineral density. Our aim was to study the combined effect of calcium and exercise on bone gain in children. Two milk-powder products containing either 800 mg of calcium phosphate (calcium) or not (placebo) were randomly allocated to 113 healthy premenarchal girls on a daily basis for 1 year. The group was composed of 63 exercise (7.2 +/- 4 hours of exercise/week) and 50 sedentary (1.2 +/- 0.8 hours of exercise/week) children. The final experiment had 4 groups: exercise/calcium (n = 12), exercise/placebo (n = 42), sedentary/calcium (n = 10), and sedentary/placebo (n = 21). Bone mineral density (BMD) at 6 skeletal sites and body composition were determined by DXA. Bone age was calculated and the daily spontaneous calcium intake was assessed by a frequency questionnaire. All the tests were performed at baseline and 1 year by the same observer. BMD gains were significantly greater in the exercise/calcium group than in other groups at the total body (increase of 6.3 %, p < 0.05), lumbar spine (11 %, p < 0.05), femoral neck (8.2 %, p < 0.02), and Ward's triangle (9.3 %, p < 0.01). There was no difference between the other groups. These data suggest that calcium supplementation increases the effect of physical exercise on bone mineral acquisition in the period preceding puberty, and that calcium supplementation without physical activity does not improve the BMD acquisition during this period. Physical exercise that stimulates bone accretion needs a high calcium intake to be completely effective.
Kim, Young-Sang; Kim, Kwang-Min; Lee, Duck-Joo; Kim, Bom-Taeck; Park, Sat-Byul; Cho, Doo-Yeoun; Suh, Chang-Hee; Kim, Hyoun-Ah; Park, Rae-Woong
2011-01-01
Little is known about hair mineral status in fibromyalgia patients. This study evaluated the characteristics of hair minerals in female patients with fibromyalgia compared with a healthy reference group. Forty-four female patients diagnosed with fibromyalgia according to the American College of Rheumatology criteria were enrolled as the case group. Ageand body mass index-matched data were obtained from 122 control subjects enrolled during visit for a regular health check-up. Hair minerals were analyzed and compared between the two groups. The mean age was 43.7 yr. General characteristics were not different between the two groups. Fibromyalgia patients showed a significantly lower level of calcium (775 µg/g vs 1,093 µg/g), magnesium (52 µg/g vs 72 µg/g), iron (5.9 µg/g vs 7.1 µg/g), copper (28.3 µg/g vs 40.2 µg/g) and manganese (140 ng/g vs 190 ng/g). Calcium, magnesium, iron, and manganese were loaded in the same factor using factor analysis; the mean of this factor was significantly lower in fibromyalgia group in multivariate analysis with adjustment for potential confounders. In conclusion, the concentrations of calcium, magnesium, iron, and manganese in the hair of female patients with fibromyalgia are lower than of controls, even after adjustment of potential confounders. PMID:22022174
Sands, Dorota; Mielus, Monika; Umławska, Wioleta; Lipowicz, Anna; Oralewska, Beata; Walkowiak, Jarosław
2015-09-01
The aim of the study was to evaluate factors related to bone formation and resorption in Polish children and adolescents with cystic fibrosis and to examine the effect of nutritional status, biochemical parameters and clinical status on bone mineral density. The study group consisted of 100 children and adolescents with cystic fibrosis with a mean age 13.4 years old. Anthropometric measurements, included body height, body mass and body mass index (BMI); bone mineral densitometry and biochemical testing were performed. Bone mineral density was measured using a dual-energy X-ray absorption densitometer. Biochemical tests included serum calcium, phosphorus, parathyroid hormone and vitamin D concentrations, as well as 24-h urine calcium and phosphorus excretion. Pulmonary function was evaluated using FEV1%, and clinical status was estimated using the Shwachman-Kulczycki score. Standardized body height, body mass and BMI were significantly lower than in the reference population. Mean serum vitamin D concentration was decreased. Pulmonary disease was generally mild, with a mean FEV1% of 81%. Multivariate linear regression revealed that the only factors that had a significant effect on bone marrow density were BMI and FEV1%. There were no significant correlations between bone mineral density and the results of any of the biochemical tests performed. Nutritional status and bone mineral density were significantly decreased in children and adolescents with cystic fibrosis. In spite of abnormalities in biochemical testing, the factors that were found to have the strongest effect on bone mineral density were standardized BMI and clinical status. Copyright © 2015. Published by Elsevier Urban & Partner Sp. z o.o.
NASA Astrophysics Data System (ADS)
Frost, Ray L.; Scholz, Ricardo; López, Andrés; Xi, Yunfei; Granja, Amanda; Žigovečki Gobac, Željka; Lima, Rosa Malena Fernandes
2013-12-01
We have studied the mineral olmiite CaMn[SiO3(OH)](OH) which forms a series with its calcium analogue poldervaartite CaCa[SiO3(OH)](OH) using a range of techniques including scanning electron microscopy, thermogravimetric analysis, Raman and infrared spectroscopy. Chemical analysis shows the mineral is pure and contains only calcium and manganese in the formula. Thermogravimetric analysis proves the mineral decomposes at 502 °C with a mass loss of 8.8% compared with the theoretical mass loss of 8.737%. A strong Raman band at 853 cm-1 is assigned to the SiO stretching vibration of the SiO3(OH) units. Two Raman bands at 914 and 953 cm-1 are attributed to the antisymmetric vibrations. Two intense Raman bands observed at 3511 and 3550 cm-1 are assigned to the OH stretching vibration of the SiO3(OH) units. The observation of multiple OH bands supports the concept of the non-equivalence of the OH units. Vibrational spectroscopy enables a detailed assessment of the molecular structure of olmiite.
NASA Astrophysics Data System (ADS)
Indriyani, N.; Tridjaja, B.; Medise, B. E.; Kurniati, N.
2017-08-01
Systemic lupus erythematosus (SLE) is an autoimmune disease affecting children; its morbidity and mortality rates are significant. One risk factor for morbidity is chronic corticosteroid use. The aim of this study is to determine the occurrence rate of low bone mineral density; discuss the characteristics, including cumulative and daily doses of corticosteroid, body mass index, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), calcium, and vitamin D intake; and assess bone metabolism laboratory parameters, including serum calcium, vitamin D, alkaline phosphatase (ALP), phosphorus, and cortisol among children with SLE receiving corticosteroids. This was a descriptive, cross-sectional study involving 16 children with SLE attending the child and adolescent outpatient clinic at Cipto Mangunkusumo Hospital in November-December 2016. Low bone mineral density occurred among 7/16 patients. The mean total bone mineral density was 0.885 ± 0.09 g/cm2. Children with SLE receiving corticosteroid had low calcium (8.69 ± 0.50 mg/dl), vitamin D (19.3 ± 5.4 mg/dl), ALP (79.50 [43.00-164.00] U/l), and morning cortisol level (1.20 [0.0-10.21] ug/dl), as well as calcium (587.58 ± 213.29 mg/d) and vitamin D (2.9 [0-31.8] mcg/d) intake. The occurrence of low bone mineral density was observed among children with SLE receiving corticosteroid treatment. Low bone mineral density tends to occur among patients with higher cumulative doses and longer duration of corticosteroid treatments.
Behavioral Intervention in Adolescents Improves Bone Mass, Yet Lactose Maldigestion Is a Barrier
Lee, Yujin; Savaiano, Dennis A.; McCabe, George P.; Pottenger, Francis M.; Welshimer, Kathleen; Weaver, Connie M.; McCabe, Linda D.; Novotny, Rachel; Read, Marsha; Going, Scott; Mason, April; Van Loan, Marta
2018-01-01
Calcium intake during adolescence is important for attainment of peak bone mass. Lactose maldigestion is an autosomal recessive trait, leading to lower calcium intake. The Adequate Calcium Today study aimed to determine if a school-based targeted behavioral intervention over one year could improve calcium intake and bone mass in early adolescent girls. The school-randomized intervention was conducted at middle schools in six states over one school year. A total of 473 girls aged 10–13 years were recruited for outcome assessments. Bone mineral content (BMC) was determined by dual energy X-ray absorptiometry. Dietary calcium intake was assessed with a semi-quantitative food frequency questionnaire. Baseline calcium intake and BMC were not significantly different between groups. After the intervention period, there were no differences in changes in calcium intake and BMC at any site between groups. An unanticipated outcome was a greater increase in spinal BMC among lactose digesters than lactose maldigesters in the intervention schools only (12 months) (6.9 ± 0.3 g vs. 6.0 ± 0.4 g, p = 0.03) and considering the entire study period (18 months) (9.9 ± 0.4 vs. 8.7 ± 0.5 g, p < 0.01). Overall, no significant differences between the intervention and control schools were observed. However, lactose digesters who received the intervention program increased bone mass to a greater extent than lactose maldigesters. PMID:29597337
The Consequences of Modern Military Deployment on Calcium Status and Bone Health
2010-01-01
Army Medical Center (MAMC) in Tacoma, Washington. At MAMC, data on diet , exercise, and bone mineral density were collected before and after...Studies of basketball players and firefighters, for example, found that athletes experienced a significant decrease in bone mass density (BMD) during the...evidence supporting the link between calcium intake and bone health. We conducted a study to help better define the links between diet , environment
Dietary calcium requirements do not differ between Mexican-American boys and girls.
Palacios, Cristina; Martin, Berdine R; McCabe, George P; McCabe, Linda; Peacock, Munro; Weaver, Connie M
2014-08-01
Mexican Americans are an understudied ethnic group for determinants of bone health, although the risk of age-related osteoporosis is high in this rapidly growing sector of the U.S. population. Thus, the objective of the present study was to establish the dietary calcium requirements for bone health in Mexican-American adolescents by measuring calcium retention calculated from balance in response to a range of dietary calcium intakes and to determine predictors of skeletal calcium retention. Adolescents aged 12-15 y were studied twice on paired calcium intakes ranging from 600 to 2300 mg/d using randomized-order, crossover 3-wk balance studies. Skeletal calcium retention was calculated as dietary calcium intake minus calcium excreted in feces and urine over the last 2 wk of balance. A linear model was developed to explain the variation in calcium retention. Boys (n = 20) were taller and had higher lean mass, usual dietary calcium intake, bone mineral content, and serum alkaline phosphatase compared with girls, whereas girls (n = 20) had higher Tanner scores and greater fat mass. Calcium retention increased with calcium intake (P < 0.0001) and did not differ by sex (P = 0.66). In boys and girls considered together, calcium intake explained 33% of the variation in calcium retention. Serum alkaline phosphatase explained an additional 11% of the variation in calcium retention. Other variables measured, including the urine N-telopeptide of type I collagen/creatinine ratio, Tanner score, serum parathyroid hormone and 25-hydroxyvitamin D, weight, height, and body mass index, did not contribute to the variance in calcium retention. In adolescence, calcium retention in both Mexican-American boys and girls was higher than determined previously in adolescent nonHispanic white girls. This trial was registered at clinicaltrials.gov as NCT01277185. © 2014 American Society for Nutrition.
Douglas, Timothy E L; Krawczyk, Grzegorz; Pamula, Elzbieta; Declercq, Heidi A; Schaubroeck, David; Bucko, Miroslaw M; Balcaen, Lieve; Van Der Voort, Pascal; Bliznuk, Vitaliy; van den Vreken, Natasja M F; Dash, Mamoni; Detsch, Rainer; Boccaccini, Aldo R; Vanhaecke, Frank; Cornelissen, Maria; Dubruel, Peter
2016-11-01
Mineralization of hydrogels, desirable for bone regeneration applications, may be achieved enzymatically by incorporation of alkaline phosphatase (ALP). ALP-loaded gellan gum (GG) hydrogels were mineralized by incubation in mineralization media containing calcium and/or magnesium glycerophosphate (CaGP, MgGP). Mineralization media with CaGP:MgGP concentrations 0.1:0, 0.075:0.025, 0.05:0.05, 0.025:0.075 and 0:0.1 (all values mol/dm 3 , denoted A, B, C, D and E, respectively) were compared. Mineral formation was confirmed by IR and Raman, SEM, ICP-OES, XRD, TEM, SAED, TGA and increases in the the mass fraction of the hydrogel not consisting of water. Ca was incorporated into mineral to a greater extent than Mg in samples mineralized in media A-D. Mg content and amorphicity of mineral formed increased in the order A < B < C < D. Mineral formed in media A and B was calcium-deficient hydroxyapatite (CDHA). Mineral formed in medium C was a combination of CDHA and an amorphous phase. Mineral formed in medium D was an amorphous phase. Mineral formed in medium E was a combination of crystalline and amorphous MgP. Young's moduli and storage moduli decreased in dependence of mineralization medium in the order A > B > C > D, but were significantly higher for samples mineralized in medium E. The attachment and vitality of osteoblastic MC3T3-E1 cells were higher on samples mineralized in media B-E (containing Mg) than in those mineralized in medium A (not containing Mg). All samples underwent degradation and supported the adhesion of RAW 264.7 monocytic cells, and samples mineralized in media A and B supported osteoclast-like cell formation. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.
Nachshon, Liat; Katz, Yitzhak
2016-03-01
The necessity of milk consumption in the western diet is a subject of intense controversy. One of the main benefits of milk is that it is the main source of dietary calcium. Calcium is a major bone mineral, mandatory for bone health. Its supply is derived exclusively from external dietary sources. During the growth period, an increased calcium supply is needed for the process of bone mass accumulation. An optimal bone mass achieved by the end of the growth period may be protective later in life against the bone mass loss that commonly occurs. This in turn, can be preventative against the occurrence of osteoporosis and the development of spontaneous bone fractures. Over the past several decades, an increased incidence of osteoporosis has been documented in western countries, leading to high rates of morbidity and mortality in the middle-aged and geriatric population. Many studies have investigated the dietary calcium requirements for different ages, to achieve and maintain proper bone health. Based on their results, guidelines concerning calcium intake in every stage of life have been published by national and international organizations. In the western diet, it is difficult to achieve the recommended calcium intake without milk consumption. Moreover, calcium bioavailability for intestinal absorption is high. Several studies have recently raised doubts concerning the amounts of calcium intake in the western diet and its effectiveness in preventing osteoporosis. The main disadvantage of these studies is their being based on the patient's past memory recall of milk consumption. Patients with IgE-mediated cow's milk protein allergy are a unique population. Their lifetime negligible milk consumption is undisputed. A recent study investigated for the first time, the bone density of young adults with milk allergy at the end of their growth period. Their severe reduction in bone mineral density and dietary calcium intake defines them as a high risk group for the development of early osteoporosis. Another finding of this study was that normal bone density was found in milk allergic patients who started to consume milk after a successful desensitization program. Interestingly, these patients had consumed milk for a period of only 12-36 months and had only partially achieved the recommended dietary intake for calcium. It appears that dietary milk is essential for optimal peak bone mass. The required amounts of calcium and the preferred form for consumption, however, requires further investigation.
Bone nutrients for vegetarians.
Mangels, Ann Reed
2014-07-01
The process of bone mineralization and resorption is complex and is affected by numerous factors, including dietary constituents. Although some dietary factors involved in bone health, such as calcium and vitamin D, are typically associated with dairy products, plant-based sources of these nutrients also supply other key nutrients involved in bone maintenance. Some research suggests that vegetarian diets, especially vegan diets, are associated with lower bone mineral density (BMD), but this does not appear to be clinically significant. Vegan diets are not associated with an increased fracture risk if calcium intake is adequate. Dietary factors in plant-based diets that support the development and maintenance of bone mass include calcium, vitamin D, protein, potassium, and soy isoflavones. Other factors present in plant-based diets such as oxalic acid and phytic acid can potentially interfere with absorption and retention of calcium and thereby have a negative effect on BMD. Impaired vitamin B-12 status also negatively affects BMD. The role of protein in calcium balance is multifaceted. Overall, calcium and protein intakes in accord with Dietary Reference Intakes are recommended for vegetarians, including vegans. Fortified foods are often helpful in meeting recommendations for calcium and vitamin D. Plant-based diets can provide adequate amounts of key nutrients for bone health. © 2014 American Society for Nutrition.
Kinetic aspects of bone mineral metabolism
NASA Technical Reports Server (NTRS)
Palmer, H. E.
1973-01-01
Two techniques were studied for measuring changes in bone mass in rats. One technique measures the Ar-37 produced from calcium during neutron irradiation and the other measures the changes in the Na-22 content which has been incorporated within the rat bone. Both methods are performed in VIVO and cause no significant physiological damage. The Ar-37 leaves the body of a rat within an hour after being produced, and it can be quantitatively collected and measured with a precision of - or + 2% on the same rat. With appropriate irradiation conditions it appears that the absolute quantity of calcuim in any rat can be determined within - or + 3% regardless of animal size. The Na-22 when uniformly distributed in bone, can be used to monitor bone mineral turnover and this has been demonstrated in conditions of calcium deficiency during growth and also pregnancy coupled with calcium deficiency.
Ozden, Ozkan; Erkan, Nuray; Ulusoy, Safak
2009-08-01
Two bivalve's species (Chamelea gallina and Donax trunculus) were investigated in terms of proximate and mineral compositions (sodium, potassium, magnesium, calcium, iodine and selenium) throughout the year. The concentrations of minerals were determined using inductively coupled plasma mass spectrometry. Ranges of moisture, protein, fat, ash and carbohydrate contents were 82.70-86.57%, 6.86-8.99%, 0.58-1.20%, 2.44-2.95% and 2.70-4.50% for C. gallina, and were 81.09-85.55%, 8.13-10.61%, 0.69-1.33%, 3.19-4.06% and 2.31-3.18% for D. trunculus, respectively. The highest sodium, potassium, magnesium, calcium, iodine and selenium contents for two species were found in the summer, followed by spring, autumn and winter. The concentrations of metals in two tissues exceeded the acceptable levels for a food source for human consumption.
Douglas, Timothy E L; Piwowarczyk, Wojciech; Pamula, Elzbieta; Liskova, Jana; Schaubroeck, David; Leeuwenburgh, Sander C G; Brackman, Gilles; Balcaen, Lieve; Detsch, Rainer; Declercq, Heidi; Cholewa-Kowalska, Katarzyna; Dokupil, Agnieszka; Cuijpers, Vincent M J I; Vanhaecke, Frank; Cornelissen, Ria; Coenye, Tom; Boccaccini, Aldo R; Dubruel, Peter
2014-08-01
Hydrogels of biocompatible calcium-crosslinkable polysaccharide gellan gum (GG) were enriched with bioglass particles to enhance (i) mineralization with calcium phosphate (CaP); (ii) antibacterial properties and (iii) growth of bone-forming cells for future bone regeneration applications. Three bioglasses were compared, namely one calcium-rich and one calcium-poor preparation both produced by a sol-gel technique (hereafter referred to as A2 and S2, respectively) and one preparation of composition close to that of the commonly used 45S5 type (hereafter referred to as NBG). Incubation in SBF for 7 d, 14 d and 21 d caused apatite formation in bioglass-containing but not in bioglass-free samples, as confirmed by FTIR, XRD, SEM, ICP-OES, and measurements of dry mass, i.e. mass attributable to polymer and mineral and not water. Mechanical testing revealed an increase in compressive modulus in samples containing S2 and NBG but not A2. Antibacterial testing using biofilm-forming meticillin-resistant staphylococcus aureus (MRSA) showed markedly higher antibacterial activity of samples containing A2 and S2 than samples containing NBG and bioglass-free samples. Cell biological characterization using rat mesenchymal stem cells (rMSCs) revealed a stimulatory effect of NBG on rMSC differentiation. The addition of bioglass thus promotes GG mineralizability and, depending on bioglass type, antibacterial properties and rMSC differentiation.
Ganpule, A; Yajnik, C S; Fall, C H D; Rao, S; Fisher, D J; Kanade, A; Cooper, C; Naik, S; Joshi, N; Lubree, H; Deshpande, V; Joglekar, C
2006-08-01
Bone mass is influenced by genetic and environmental factors. Recent studies have highlighted associations between maternal nutritional status during pregnancy and bone mass in the offspring. We hypothesized that maternal calcium intakes and circulating micronutrients during pregnancy are related to bone mass in Indian children. DESIGN/SETTING/PARTICIPANTS/MAIN OUTCOME MEASURES: Nutritional status was measured at 18 and 28 wk gestation in 797 pregnant rural Indian women. Measurements included anthropometry, dietary intakes (24-h recall and food frequency questionnaire), physical workload (questionnaire), and circulating micronutrients (red cell folate and plasma ferritin, vitamin B12, and vitamin C). Six years postnatally, total body and total spine bone mineral content and bone mineral density (BMD) were measured using dual-energy x-ray absorptiometry (DXA) in the children (n = 698 of 762 live births) and both parents. Both parents' DXA measurements were positively correlated with the equivalent measurements in the children (P < 0.001 for all). The strength of these correlations was similar for fathers and mothers. Children of mothers who had a higher frequency of intake of calcium-rich foods during pregnancy (milk, milk products, pulses, non-vegetarian foods, green leafy vegetables, fruit) had higher total and spine bone mineral content and BMD, and children of mothers with higher folate status at 28 wk gestation had higher total and spine BMD, independent of parental size and DXA measurements. Modifiable maternal nutritional factors may influence bone health in the offspring. Fathers play a role in determining their child's bone mass, possibly through genetic mechanisms or through shared environment.
The three-dimensional distribution of minerals in potato tubers
Subramanian, Nithya K.; White, Philip J.; Broadley, Martin R.; Ramsay, Gavin
2011-01-01
Background and Aims The three-dimensional distributions of mineral elements in potato tubers provide insight into their mechanisms of transport and deposition. Many of these minerals are essential to a healthy human diet, and characterizing their distribution within the potato tuber will guide the effective utilization of this staple foodstuff. Methods The variation in mineral composition within the tuber was determined in three dimensions, after determining the orientation of the harvested tuber in the soil. The freeze-dried tuber samples were analysed for minerals using inductively coupled plasma-mass spectrometry (ICP-MS). Minerals measured included those of nutritional significance to the plant and to human consumers, such as iron, zinc, copper, calcium, magnesium, manganese, phosphorus, potassium and sulphur. Key Results The concentrations of most minerals were higher in the skin than in the flesh of tubers. The potato skin contained about 17 % of total tuber zinc, 34 % of calcium and 55 % of iron. On a fresh weight basis, most minerals were higher in tuber flesh at the stem end than the bud end of the tuber. Potassium, however, displayed a gradient in the opposite direction. The concentrations of phosphorus, copper and calcium decreased from the periphery towards the centre of the tuber. Conclusions The distribution of minerals varies greatly within the potato tuber. Low concentrations of some minerals relative to those in leaves may be due to their low mobility in phloem, whereas high concentrations in the skin may reflect direct uptake from the soil across the periderm. In tuber flesh, different minerals show distinct patterns of distribution in the tuber, several being consistent with phloem unloading in the tuber and limited onward movement. These findings have implications both for understanding directed transport of minerals in plants to stem-derived storage organs and for the dietary implications of different food preparation methods for potato tubers. PMID:21289026
Calcium absorption from fortified ice cream formulations compared with calcium absorption from milk.
van der Hee, Regine M; Miret, Silvia; Slettenaar, Marieke; Duchateau, Guus S M J E; Rietveld, Anton G; Wilkinson, Joy E; Quail, Patricia J; Berry, Mark J; Dainty, Jack R; Teucher, Birgit; Fairweather-Tait, Susan J
2009-05-01
Optimal bone mass in early adulthood is achieved through appropriate diet and lifestyle, thereby protecting against osteoporosis and risk of bone fracture in later life. Calcium and vitamin D are essential to build adequate bones, but calcium intakes of many population groups do not meet dietary reference values. In addition, changes in dietary patterns are exacerbating the problem, thereby emphasizing the important role of calcium-rich food products. We have designed a calcium-fortified ice cream formulation that is lower in fat than regular ice cream and could provide a useful source of additional dietary calcium. Calcium absorption from two different ice cream formulations was determined in young adults and compared with milk. Sixteen healthy volunteers (25 to 45 years of age), recruited from the general public of The Netherlands, participated in a randomized, reference-controlled, double-blind cross-over study in which two test products and milk were consumed with a light standard breakfast on three separate occasions: a standard portion of ice cream (60 g) fortified with milk minerals and containing a low level (3%) of butter fat, ice cream (60 g) fortified with milk minerals and containing a typical level (9%) of coconut oil, and reduced-fat milk (1.7% milk fat) (200 mL). Calcium absorption was measured by the dual-label stable isotope technique. Effects on calcium absorption were evaluated by analysis of variance. Fractional absorption of calcium from the 3% butterfat ice cream, 9% coconut oil ice cream, and milk was 26%+/-8%, 28%+/-5%, and 31%+/-9%, respectively, and did not differ significantly (P=0.159). Results indicate that calcium bioavailability in the two calcium-fortified ice cream formulations used in this study is as high as milk, indicating that ice cream may be a good vehicle for delivery of calcium.
Vittori, Miloš; Rozman, Alenka; Grdadolnik, Jože; Novak, Urban; Štrus, Jasna
2013-01-01
Crustacean calcium bodies are epithelial sacs which contain a mineralized matrix. The objectives of this study were to describe the microscopic anatomy of calcium bodies in the terrestrial isopod Hyloniscus riparius and to establish whether they undergo molt-related structural changes. We performed 3D reconstruction of the calcium bodies from paraffin sections and analyzed their structure with light and electron microscopy. In addition, we analyzed the chemical composition of their mineralized matrices with micro-Raman spectroscopy. Two pairs of these organs are present in H. riparius. One pair is filled with bacteria while the other pair is not. In non-molting animals, the bacteria-filled calcium bodies contain apatite crystals and the bacteria-free calcium bodies enclose CaCO3-containing concretions with little organic matrix. During preparation for molt, an additional matrix layer is deposited in both pairs of calcium bodies. In the bacteria-filled calcium bodies it contains a mixture of calcium carbonate and calcium phosphate, whereas only calcium carbonate is present in bacteria-free calcium bodies. After ecdysis, all mineral components in bacteria-free calcium bodies and the additional matrix layer in bacteria-filled calcium bodies are completely resorbed. During calcium resorption, the apical surface of the calcium body epithelium is deeply folded and electron dense granules are present in spaces between epithelial cells. Our results indicate that the presence of bacteria might be linked to calcium phosphate mineralization. Calcium bodies likely provide a source of calcium and potentially phosphate for the mineralization of the new cuticle after molt. Unlike other terrestrial isopods, H. riparius does not form sternal CaCO3 deposits and the bacteria-free calcium bodies might functionally replace them in this species.
Vittori, Miloš; Rozman, Alenka; Grdadolnik, Jože; Novak, Urban; Štrus, Jasna
2013-01-01
Crustacean calcium bodies are epithelial sacs which contain a mineralized matrix. The objectives of this study were to describe the microscopic anatomy of calcium bodies in the terrestrial isopod Hyloniscus riparius and to establish whether they undergo molt-related structural changes. We performed 3D reconstruction of the calcium bodies from paraffin sections and analyzed their structure with light and electron microscopy. In addition, we analyzed the chemical composition of their mineralized matrices with micro-Raman spectroscopy. Two pairs of these organs are present in H. riparius. One pair is filled with bacteria while the other pair is not. In non-molting animals, the bacteria-filled calcium bodies contain apatite crystals and the bacteria-free calcium bodies enclose CaCO3-containing concretions with little organic matrix. During preparation for molt, an additional matrix layer is deposited in both pairs of calcium bodies. In the bacteria-filled calcium bodies it contains a mixture of calcium carbonate and calcium phosphate, whereas only calcium carbonate is present in bacteria-free calcium bodies. After ecdysis, all mineral components in bacteria-free calcium bodies and the additional matrix layer in bacteria-filled calcium bodies are completely resorbed. During calcium resorption, the apical surface of the calcium body epithelium is deeply folded and electron dense granules are present in spaces between epithelial cells. Our results indicate that the presence of bacteria might be linked to calcium phosphate mineralization. Calcium bodies likely provide a source of calcium and potentially phosphate for the mineralization of the new cuticle after molt. Unlike other terrestrial isopods, H. riparius does not form sternal CaCO3 deposits and the bacteria-free calcium bodies might functionally replace them in this species. PMID:23554963
Gątarska, Anna; Tońska, Elżbieta; Ciborska, Joanna
2016-01-01
Natural mineral waters may be an essential source of calcium, magnesium and other minerals. In bottled waters, minerals occur in an ionized form which is very well digestible. However, the concentration of minerals in underground waters (which constitute the material for the production of bottled waters) varies. In view of the above, the type of water consumed is essential. The aim of the study was to estimate the calcium and magnesium contents in products available on the market and to evaluate calcium and magnesium consumption with natural mineral water by different consumer groups with an assumed volume of the consumed product. These represented forty different brands of natural mineral available waters on Polish market. These waters were produced in Poland or other European countries. Among the studied products, about 30% of the waters were imported from Lithuania, Latvia, Czech Republic, France, Italy and Germany. The content of calcium and magnesium in mineral waters was determined using flame atomic absorption spectrometry in an acetylene-air flame. Further determinations were carried out using atomic absorption spectrometer--ICE 3000 SERIES-THERMO-England, equipped with a GLITE data station, background correction (a deuterium lamp) as well as other cathode lamps. Over half of the analysed natural mineral waters were medium-mineralized. The natural mineral waters available on the market can be characterized by a varied content of calcium and magnesium and a high degree of product mineralization does not guarantee significant amounts of these components. Among the natural mineral waters available on the market, only a few feature the optimum calcium-magnesium proportion (2:1). Considering the mineralization degree of the studied products, it can be stated that the largest percentage of products with significant calcium and magnesium contents can be found in the high-mineralized water group. For some natural mineral waters, the consumption of 1 litre daily may ensure the recommended intake levels of calcium and magnesium in some consumer groups to a considerable degree. For 1-3-year-old children it is recommended to consume less than 1 litre daily of natural mineral waters containing an excess of 700 mg of calcium and 80 mg of magnesium in 1 litre.
Variations in Urine Calcium Isotope: Composition Reflect Changes in Bone Mineral Balance in Humans
NASA Technical Reports Server (NTRS)
Skulan, Joseph; Anbar, Ariel; Bullen, Thomas; Puzas, J. Edward; Shackelford, Linda; Smith, Scott M.
2004-01-01
Changes in bone mineral balance cause rapid and systematic changes in the calcium isotope composition of human urine. Urine from subjects in a 17 week bed rest study was analyzed for calcium isotopic composition. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism indicates the calcium isotope composition of urine reflects changes in bone mineral balance. Urine calcium isotope composition probably is affected by both bone metabolism and renal processes. Calcium isotope. analysis of urine and other tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.
Calcium phosphate mineralization is widely applied in crustacean mandibles.
Bentov, Shmuel; Aflalo, Eliahu D; Tynyakov, Jenny; Glazer, Lilah; Sagi, Amir
2016-02-24
Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, crayfishes, prawns and shrimps) shifted toward the formation of calcium phosphate as the main mineral at specified locations of the mandibular teeth. In these structures, calcium phosphate is not merely co-precipitated with the bulk calcium carbonate but rather creates specialized structures in which a layer of calcium phosphate, frequently in the form of crystalline fluorapatite, is mounted over a calcareous "jaw". From a functional perspective, the co-existence of carbonate and phosphate mineralization demonstrates a biomineralization system that provides a versatile route to control the physico-chemical properties of skeletal elements. This system enables the deposition of amorphous calcium carbonate, amorphous calcium phosphate, calcite and apatite at various skeletal locations, as well as combinations of these minerals, to form graded composites materials. This study demonstrates the widespread occurrence of the dual mineralization strategy in the Malacostraca, suggesting that in terms of evolution, this feature of phosphatic teeth did not evolve independently in the different groups but rather represents an early common trait.
Calcium phosphate mineralization is widely applied in crustacean mandibles
Bentov, Shmuel; Aflalo, Eliahu D.; Tynyakov, Jenny; Glazer, Lilah; Sagi, Amir
2016-01-01
Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, crayfishes, prawns and shrimps) shifted toward the formation of calcium phosphate as the main mineral at specified locations of the mandibular teeth. In these structures, calcium phosphate is not merely co-precipitated with the bulk calcium carbonate but rather creates specialized structures in which a layer of calcium phosphate, frequently in the form of crystalline fluorapatite, is mounted over a calcareous “jaw”. From a functional perspective, the co-existence of carbonate and phosphate mineralization demonstrates a biomineralization system that provides a versatile route to control the physico-chemical properties of skeletal elements. This system enables the deposition of amorphous calcium carbonate, amorphous calcium phosphate, calcite and apatite at various skeletal locations, as well as combinations of these minerals, to form graded composites materials. This study demonstrates the widespread occurrence of the dual mineralization strategy in the Malacostraca, suggesting that in terms of evolution, this feature of phosphatic teeth did not evolve independently in the different groups but rather represents an early common trait. PMID:26906263
Friedman, Michael A.; Bailey, Alyssa M.; Rondon, Matthew J.; McNerny, Erin M.; Sahar, Nadder D.; Kohn, David H.
2016-01-01
Exercise has long-lasting benefits to bone health that may help prevent fractures by increasing bone mass, bone strength, and tissue quality. Long-term exercise of 6–12 weeks in rodents increases bone mass and bone strength. However, in growing mice, a short-term exercise program of 3 weeks can limit increases in bone mass and structural strength, compared to non-exercised controls. Short-term exercise can, however, increase tissue strength, suggesting that exercise may create competition for minerals that favors initially improving tissue-level properties over structural-level properties. It was therefore hypothesized that adding calcium and phosphorus supplements to the diet may prevent decreases in bone mass and structural strength during a short-term exercise program, while leading to greater bone mass and structural strength than exercise alone after a long-term exercise program. A short-term exercise experiment was done for 3 weeks, and a long-term exercise experiment was done for 8 weeks. For each experiment, male 16-week old C57BL/6 mice were assigned to 4 weight-matched groups–exercise and non-exercise groups fed a control or mineral-supplemented diet. Exercise consisted of treadmill running at 12 m/min, 30 min/day for 7 days/week. After 3 weeks, exercised mice fed the supplemented diet had significantly increased tibial tissue mineral content (TMC) and cross-sectional area over exercised mice fed the control diet. After 8 weeks, tibial TMC, cross-sectional area, yield force, and ultimate force were greater from the combined treatments than from either exercise or supplemented diet alone. Serum markers of bone formation (PINP) and resorption (CTX) were both decreased by exercise on day 2. In exercised mice, day 2 PINP was significantly positively correlated with day 2 serum Ca, a correlation that was weaker and negative in non-exercised mice. Increasing dietary mineral consumption during an exercise program increases bone mass after 3 weeks and increases structural strength after 8 weeks, making bones best able to resist fracture. PMID:27008546
[Dietary patterns in college freshmen and its relation to bone mineral density].
Wang, Sufang; Mu, Min; Zhao, Yan; Wang, Xiaoqin; Shu, Long; Li, Qingyan; Li, Yingchun
2012-07-01
In order to investigate the bone density of freshmen, and to analyze the association between dietary pattern and bone mineral density (BMD). A questionnaire survey on the situation of dietary pattern was conducted in 1414 freshmen. Effective dietary survey questionnaires and bone mineral density measurements were completed for 1319 participants. Bone mass was assessed by using an Ultrasound Bone Densitometer on the right calcaneus (CM-200, Furuno Electric Corporation, Japan), and the speed of sound (SOS, m/s) was used as an indicator for bone density. Factor analysis with varimax rotation was used to identify the dietary patterns. After adjusting for confounders, covariance with Bonferroni's was used to further examine the associations between dietary patterns and bone mineral density (BMD). (1) Four major dietary patterns were noticed. Western food pattern (high consumption in hamburger, fried food, nuts, biscuit, chocolate, cola, coffee, sugars). Animal protein pattern (high consumption in pork, mutton, beef, poultry meat, animal liver). Calcium pattern (high consumption in fresh fruits, eggs, fish and shrimps, kelp laver and sea fish, milk and dairy products, beans and bean products). Traditional Chinese pattern (high consumption in rice and grain, fresh fruits, fresh vegetables, pork). (2) No association was observed between the western food pattern and bone mineral density. High animal protein pattern showed lower SOS value compared with low animal protein pattern. High calcium pattern showed higher SOS value compared with low calcium pattern. High traditional Chinese pattern showed higher SOS value compared with the low traditional Chinese pattern. Dietary patterns are closely related with bone mineral density (BMD) of freshmen.
Vittori, Miloš; Kostanjšek, Rok; Znidaršič, Nada; Zagar, Kristina; Ceh, Miran; Strus, Jasna
2012-10-01
Crustaceans form a variety of calcium deposits in which they store calcium necessary for the mineralization of their exoskeletons. Calcium bodies, organs containing large amounts of calcium, have been reported in some terrestrial isopod crustaceans, but have not yet been extensively studied. We analyzed the architecture of these organs during the molt cycle in the isopod Titanethes albus. Two pairs of calcium bodies are positioned ventrolaterally in posterior pereonites of T. albus. Individual organs are epithelial sacs that contain material arranged in concentric layers delimited by thin laminae. As demonstrated by electron microscopy and fluorescence in situ hybridization, abundant bacteria are present within the calcium bodies. Regardless of the molt cycle stage, crystalline concretions are present in the central areas of the calcium bodies. Energy dispersive X-ray spectrometry of the concretions demonstrated that they are composed predominantly of calcium and phosphorus and selected area electron diffraction indicated the presence of hydroxyapatite. In molting animals, a glassy layer of mineralized matrix is formed between the envelope and the outermost lamina of the calcium body. This layer consists of an amorphous calcium mineral which contains less phosphorus than the central concretions and is resorbed after molt. Since changes in the mineralized matrix are synchronized with the molt cycle, the calcium bodies likely function as a storage compartment that complements sternal deposits as a source of calcium for the mineralization of the exoskeleton. Bacteria associated with the mineralized matrix of calcium bodies are evidently involved in calcium dynamics. Copyright © 2012 Elsevier Inc. All rights reserved.
Alissa, Eman M; Alnahdi, Wafa A; Alama, Nabeel; Ferns, Gordon A
2014-01-01
Osteoporosis remains a major health problem in all developed countries and is a condition in which several dietary factors have been implicated. To assess the nutritional status and levels of adiposity of postmenopausal women in relation to bone mineral density. A cross-sectional study in which dietary intake was estimated by a food frequency questionnaire in 300 Saudi postmenopausal women aged 46-88 years. Bone profile biochemistry (serum calcium, phosphate, parathyroid hormone [PTH], vitamin D) and bone mineral density (BMD) in 3 skeletal sites were determined for all participants. Overweight and obesity were highly prevalent among the study population. No significant correlation was found between dietary calcium and vitamin D and bone mass at any site. Dietary intake of calcium and vitamin D was significantly less than the recommended levels for a large proportion of the cohort. Energy-adjusted intakes of carbohydrates, fat, protein, and unsaturated fatty acids were associated with BMD in the postmenopausal women. Age, body weight, and residency type were predictors of BMD at all sites. Serum-intact PTH was a predictor of BMD at lumbar spine and femoral neck. Waist : hip ratio (WHR) was a predictor for BMD at femoral neck. These results suggest that BMD is influenced by dietary factors other than calcium and vitamin D. However, nondietary factors such as age, WHR, PTH, and body weight may be important determinants of BMD in postmenopausal women.
Greupner, Theresa; Schneider, Inga; Hahn, Andreas
2017-07-01
The aim of the present study was to compare the bioavailability of calcium from 3 mineral waters with different concentrations of minerals with that of milk and a calcium supplement. A single-center, randomized controlled trial with a crossover design with 21 healthy men and women was conducted at the Institute of Food Science and Human Nutrition, Leibniz University Hannover. The participants consumed the 5 test products providing 300 mg of calcium each on 5 examination days with 1-week wash-out phases in between. Primary outcome variables were the area under the curve of serum calcium levels for 10-hour (AUC 0-10h ) and 24-hour urinary calcium excretion. In all groups, no significant differences in the AUC 0-10h of serum calcium levels as well as in the 24-hour urinary calcium excretion were observed. Likewise, mean changes in serum phosphate and urinary phosphate, as well as serum parathormone, showed no differences between the groups. Given an equivalent bioavailability of calcium in all test products, neither a high concentration of SO 4 2- or of HCO 3 influenced the bioavailability of calcium. Accordingly, the use of mineral water with high concentrations of calcium constitutes a calorie-free calcium source that can improve calcium supply.
Fukushima, Yoichi; Kumagai, Akiko
2006-10-01
Calcium is not sufficiently consumed by Japanese at any age groups. Childhood is an important period, when they should earn bone minerals to reach higher peak bone mass for reducing the risk of osteoporosis in their later life. Children require higher calcium consumption per body weight than adults, and also establish their dietary pattern in this period. MILO has attracted widespread popularity as a good-taste chocolate-flavored malt drink with balanced nutrients for children. We developed FOSHU MILO with fructooligosaccharides (FOS) aiming at improving absorption of calcium, which is originally rich in the products. Using the calcium stable isotope (44)Ca, we found that the urinary excretion in the subject fed the products with FOS was higher than that of control product without FOS, suggesting that the FOSHU MILO is effective in promoting calcium absorption from the intestines. MILO could contribute to bone health by increasing consumption of calcium and/or improving the calcium bioavailability.
NASA Astrophysics Data System (ADS)
Sullivan, Ryan Christopher
Mineral dust particles are a major component of tropospheric aerosol mass and affect regional and global atmospheric chemistry and climate. Dust particles experience heterogeneous reactions with atmospheric gases that alter the gas and particle-phase chemistry. These in turn influence the warm and cold cloud nucleation ability and optical properties of the dust particles. This dissertation investigates the atmospheric chemistry of mineral dust particles and their role in warm cloud nucleation through a combination of synergistic field measurements, laboratory experiments, and theoretical modeling. In-situ measurements made with a single-particle mass spectrometer during the ACE-Asia field campaign in 2001 provide the motivation for this work. The observed mixing state of the individual ambient particles with secondary organic and inorganic components is described in Chapter 2. A large Asian dust storm occurred during the campaign and produced dramatic changes in the aerosol's composition and mixing state. The effect of particle size and mineralogy on the atmospheric processing of individual dust particles is explored in Chapters 3 & 4. Sulfate was found to accumulate preferentially in submicron iron and aluminosilicate-rich dust particles, while nitrate and chloride were enriched in supermicron calcite-rich dust. The mineral dust (and sea salt particles) were also enriched in oxalic acid, the dominant component of water soluble organic carbon. Chapter 5 explores the roles of gas-phase photochemistry and partitioning of the diacids to the alkaline particles in producing this unique behavior. The effect of the dust's mixing state with secondary organic and inorganic components on the dust particles' solubility, hygroscopicity, and thus warm cloud nucleation properties is explored experimentally and theoretically in Chapter 6. Cloud condensation nucleation (CCN) activation curves revealed that while calcium nitrate and calcium chloride particles were very hygroscopic and CCN-active, due to the high solubility of these compounds, calcium sulfate and calcium oxalate were not. Particles composed of these two sparingly soluble compounds had apparent hygroscopicities similar to pure calcium carbonate. This implies that the commonly made assumption that all dust particles become more hygroscopic after atmospheric processing must be revisited. Calcium sulfate and oxalate represent two forms of aged mineral dust particles that remain non-hygroscopic and thus have poor CCN nucleation ability. The particle generation method (dry versus wet) was found to significantly affect the chemistry and hygroscopicity of the aerosolized particles. Finally, in Chapter 7 the timescale for the atmospheric conversion of insoluble calcite particles to soluble, CCN-active calcium nitrate particles was derived from aerosol flow tube experiments. The reaction rate is rapid was used to estimate the conversion of calcite particles to very hygroscopic particles can occur in just a few hours of exposure to tropospheric levels of nitric acid. This process will therefore be controlled by the availability of nitric acid and its precursors, as opposed to the available atmospheric reaction time.
Intestinal absorption and renal reabsorption of calcium throughout postnatal development
Beggs, Megan R
2017-01-01
Calcium is vital for many physiological functions including bone mineralization. Postnatal deposition of calcium into bone is greatest in infancy and continues through childhood and adolescence until peek mineral density is reached in early adulthood. Thereafter, bone mineral density remains static until it eventually declines in later life. A positive calcium balance, i.e. more calcium absorbed than excreted, is crucial to bone deposition during growth and thus to peek bone mineral density. Dietary calcium is absorbed from the intestine into the blood. It is then filtered by the renal glomerulus and either reabsorbed by the tubule or excreted in the urine. Calcium can be (re)absorbed across intestinal and renal epithelia via both transcellular and paracellular pathways. Current evidence suggests that significant intestinal and renal calcium transport changes occur throughout development. However, the molecular details of these alterations are incompletely delineated. Here we first briefly review the current model of calcium transport in the intestine and renal tubule in the adult. Then, we describe what is known with regard to calcium handling through postnatal development, and how alterations may aid in mediating a positive calcium balance. The role of transcellular and paracellular calcium transport pathways and the contribution of specific intestinal and tubular segments vary with age. However, the current literature highlights knowledge gaps in how specifically intestinal and renal calcium (re)absorption occurs early in postnatal development. Future research should clarify the specific changes in calcium transport throughout early postnatal development including mediators of these alterations enabling appropriate bone mineralization. Impact statement This mini review outlines the current state of knowledge pertaining to the molecules and mechanisms maintaining a positive calcium balance throughout postnatal development. This process is essential to achieving optimal bone mineral density in early adulthood, thereby lowering the lifetime risk of osteoporosis. PMID:28346014
Douglas, Timothy E L; Łapa, Agata; Samal, Sangram Keshari; Declercq, Heidi A; Schaubroeck, David; Mendes, Ana C; der Voort, Pascal Van; Dokupil, Agnieszka; Plis, Agnieszka; De Schamphelaere, Karel; Chronakis, Ioannis S; Pamuła, Elżbieta; Skirtach, Andre G
2017-12-01
Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration. Calcium carbonate (CaCO 3 ) has been successfully applied as a bone regeneration material, but hydrogel-CaCO 3 composites have received less attention. Magnesium (Mg) has been used as a component of calcium phosphate biomaterials to stimulate bone-forming cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In the present study, gellan gum (GG) hydrogels were mineralized enzymatically with CaCO 3 , Mg-enriched CaCO 3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing the magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite (Mg 5 (CO 3 ) 4 (OH) 2 .4H 2 O) formed at high magnesium concentration in the absence of calcium. The amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. The calcium:magnesium elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels with calcite or magnesian calcite promoted adhesion and growth of osteoblast-like cells. Hydrogels mineralized with hydromagnesite displayed higher cytotoxicity. In conclusion, enzymatic mineralization of GG hydrogels with CaCO 3 in the form of calcite successfully reinforced hydrogels and promoted osteoblast-like cell adhesion and growth, but magnesium enrichment had no definitive positive effect. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Simon, M J K; Beil, F T; Rüther, W; Busse, B; Koehne, T; Steiner, M; Pogoda, P; Ignatius, A; Amling, M; Oheim, R
2014-07-01
Chronic environmental fluoride exposure under calcium stress causes fragility fractures due to osteoporosis and bone quality deterioration, at least in sheep. Proof of skeletal fluorosis, presenting without increased bone density, calls for a review of fracture incidence in areas with fluoridated groundwater, including an analysis of patients with low bone mass. Understanding the skeletal effects of environmental fluoride exposure especially under calcium stress remains an unmet need of critical importance. Therefore, we studied the skeletal phenotype of sheep chronically exposed to highly fluoridated water in the Kalahari Desert, where livestock is known to present with fragility fractures. Dorper ewes from two flocks in Namibia were studied. Chemical analyses of water, blood and urine were executed for both cohorts. Skeletal phenotyping comprised micro-computer tomography (μCT), histological, histomorphometric, biomechanical, quantitative backscattered electron imaging (qBEI) and energy-dispersive X-ray (EDX) analysis. Analysis was performed in direct comparison with undecalcified human iliac crest bone biopsies of patients with fluoride-induced osteopathy. The fluoride content of water, blood and urine was significantly elevated in the Kalahari group compared to the control. Surprisingly, a significant decrease in both cortical and trabecular bones was found in sheep chronically exposed to fluoride. Furthermore, osteoid parameters and the degree and heterogeneity of mineralization were increased. The latter findings are reminiscent of those found in osteoporotic patients with treatment-induced fluorosis. Mechanical testing revealed a significant decrease in the bending strength, concurrent with the clinical observation of fragility fractures in sheep within an area of environmental fluoride exposure. Our data suggest that fluoride exposure with concomitant calcium deficit (i) may aggravate bone loss via reductions in mineralized trabecular and cortical bone mass and (ii) can cause fragility fractures and (iii) that the prevalence of skeletal fluorosis especially due to groundwater exposure should be reviewed in many areas of the world as low bone mass alone does not exclude fluorosis.
Schmalenberger, A.; Duran, A. L.; Bray, A. W.; Bridge, J.; Bonneville, S.; Benning, L. G.; Romero-Gonzalez, M. E.; Leake, J. R.; Banwart, S. A.
2015-01-01
Trees and their associated rhizosphere organisms play a major role in mineral weathering driving calcium fluxes from the continents to the oceans that ultimately control long-term atmospheric CO2 and climate through the geochemical carbon cycle. Photosynthate allocation to tree roots and their mycorrhizal fungi is hypothesized to fuel the active secretion of protons and organic chelators that enhance calcium dissolution at fungal-mineral interfaces. This was tested using 14CO2 supplied to shoots of Pinus sylvestris ectomycorrhizal with the widespread fungus Paxillus involutus in monoxenic microcosms, revealing preferential allocation by the fungus of plant photoassimilate to weather grains of limestone and silicates each with a combined calcium and magnesium content of over 10 wt.%. Hyphae had acidic surfaces and linear accumulation of weathered calcium with secreted oxalate, increasing significantly in sequence: quartz, granite < basalt, olivine, limestone < gabbro. These findings confirmed the role of mineral-specific oxalate exudation in ectomycorrhizal weathering to dissolve calcium bearing minerals, thus contributing to the geochemical carbon cycle. PMID:26197714
NASA Astrophysics Data System (ADS)
Schmalenberger, A.; Duran, A. L.; Bray, A. W.; Bridge, J.; Bonneville, S.; Benning, L. G.; Romero-Gonzalez, M. E.; Leake, J. R.; Banwart, S. A.
2015-07-01
Trees and their associated rhizosphere organisms play a major role in mineral weathering driving calcium fluxes from the continents to the oceans that ultimately control long-term atmospheric CO2 and climate through the geochemical carbon cycle. Photosynthate allocation to tree roots and their mycorrhizal fungi is hypothesized to fuel the active secretion of protons and organic chelators that enhance calcium dissolution at fungal-mineral interfaces. This was tested using 14CO2 supplied to shoots of Pinus sylvestris ectomycorrhizal with the widespread fungus Paxillus involutus in monoxenic microcosms, revealing preferential allocation by the fungus of plant photoassimilate to weather grains of limestone and silicates each with a combined calcium and magnesium content of over 10 wt.%. Hyphae had acidic surfaces and linear accumulation of weathered calcium with secreted oxalate, increasing significantly in sequence: quartz, granite < basalt, olivine, limestone < gabbro. These findings confirmed the role of mineral-specific oxalate exudation in ectomycorrhizal weathering to dissolve calcium bearing minerals, thus contributing to the geochemical carbon cycle.
Regulation of bone mineral loss during lactation
NASA Technical Reports Server (NTRS)
Brommage, R.; Deluca, H. F.
1985-01-01
The effects of varyng dietary calcium and phosphorous levels, vitamin D deficiency, oophorectomy, adrenalectomy, and simultaneous pregnancy on bone mineral loss during lactation in rats are studied. The experimental procedures and evaluations are described. The femur ash weight of lactating and nonlactating rats are calculated. The data reveals that a decrease in dietary calcium of 0.02 percent results in an increased loss of bone mineral, an increase in calcium to 1.4 percent does not lessen bone mineral loss, and bone mineral loss in vitamin D deficient rats is independent of calcium levels. It is observed that changes in dietary phosphorous level, oophorectomy, adrenalectomy, and simultaneous pragnancy do not reduce bone mineral loss during lactation. The analysis of various hormones to determine the mechanism that triggers bone mineral loss during lactation is presented.
Reduced bone mass in Dutch adolescents fed a macrobiotic diet in early life.
Parsons, T J; van Dusseldorp, M; van der Vliet, M; van de Werken, K; Schaafsma, G; van Staveren, W A
1997-09-01
This study investigated the effect of a macrobiotic (vegan-type) diet, low in calcium and vitamin D, consumed in early life, on bone mineral during adolescence. Bone mineral content (BMC) and bone area were measured in 195 adolescents (103 girls, 92 boys) aged 9-15 years, using dual-energy X-ray absorptiometry. Ninety-three adolescents (43 girls, 50 boys) had followed a macrobiotic diet in childhood, and 102 (60 girls, 42 boys) were control subjects. After adjustment for bone area, weight, height, percent body lean, age, and puberty, BMC was significantly lower in macrobiotic subjects, in boys and girls, respectively, at the whole body, -3.4% and -2.5%, spine, -8.5% and -5.0%, femoral neck, -8.0% and -8.2%, midshaft radius, -6.8% and -5.6%, and also in girls, at the trochanter, -5.8% (p < 0.05). No group differences were observed at the wrist. Group differences were not explained by current calcium adjusted bone mass at age 9-15 years, observations which may hold important implications for fracture risk in later life.
Vitoria, Isidro; Maraver, Francisco; Ferreira-Pêgo, Cíntia; Armijo, Francisco; Moreno Aznar, Luis; Salas-Salvadó, Jordi
2014-07-01
A sufficient intake of calcium enables correct bone mineralization. The bioavailability of calcium in water is similar to that in milk. To determine the concentration of calcium in public drinking water and bottled mineral water. We used ion chromatography to analyse the calcium concentrations of public drinking waters in a representative sample of 108 Spanish municipalities (21,290,707 people) and of 109 natural mineral waters sold in Spain, 97 of which were produced in Spain and 12 of which were imported. The average calcium concentration of public drinking waters was 38.96 ± 32.44 mg/L (range: 0.40- 159.68 mg/L). In 27 municipalities, the water contained 50-100 mg/L of calcium and in six municipalities it contained over 100 mg/L. The average calcium concentration of the 97 Spanish natural mineral water brands was 39.6 mg/L (range: 0.6-610.1 mg/L). Of these, 34 contained 50-100 mg/L of calcium and six contained over 100 mg/L. Of the 12 imported brands, 10 contained over 50 mg/L. Assuming water consumption is as recommended, water containing 50-100 mg/L of calcium provides 5.4-12.8% of the recommended intake of calcium for children aged one to thirteen, up to 13.6% for adolescents, 5.8-17.6% for adults, and up to 20.8% for lactating mothers. Water with 100-150 mg/L of calcium provides 10-31% of the recommended dietary allowance, depending on the age of the individual. Public drinking water and natural mineral water consumption in a third of Spanish cities can be considered an important complementary source of calcium. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Nabatov, Alexey A; Troegubova, Natalya A; Gilmutdinov, Ruslan R; Sereda, Andrey P; Samoilov, Alexander S; Rylova, Natalya V
2017-09-01
Active physical exercises and growth are associated with mineral imbalances in young athletes. The purpose of this study was to examine the impact of sport-related factors on tissue mineral status in adolescent female athletes. Saliva and hair samples were used for the analysis of immediate and more permanent tissue mineral status, respectively. Samples taken from a control non-athletic female group and two groups of female athletes (field hockey and fencing) were analyzed for seven essential minerals: calcium, chromium, iron, potassium, magnesium, selenium and zinc. Inductively-coupled plasma mass spectrometry was used for the quantification of elements having very low concentration range in samples (Se, Cr and Zn) whereas inductively coupled plasma optical emission spectrometry was used for quantification of more ubiquitous elements (Mg, К, Са, Fe). The obtained results for athletic groups were compared with control. Female athletes had increased levels of selenium in both saliva and hair as well as chromium in saliva. Field hockey players had the higher level of zinc in hair whereas fencers had the lower levels of salivary calcium. Strong negative correlation between potassium levels in saliva and hair was identified. Iron and magnesium did not differ between the studied groups. In conclusion, novel sport-specific features of chromium tissue levels in female athletes were found. The studied sport disciplines have different impact on the distribution of osteoporosis-related minerals (calcium and zinc). Our finding can help in the development of osteoporosis preventive trainings and in the proper nutrient supplementation to correct mineral imbalances in female athletes. Copyright © 2016 Elsevier GmbH. All rights reserved.
Calcium Absorption from Fortified Ice Cream Formulations Compared with Calcium Absorption from Milk
van der Hee, Regine M.; Miret, Silvia; Slettenaar, Marieke; Duchateau, Guus S.M.J.E.; Rietveld, Anton G.; Wilkinson, Joy E.; Quail, Patricia J.; Berry, Mark J.; Dainty, Jack R.; Teucher, Birgit; Fairweather-Tait, Susan J.
2009-01-01
Objective Optimal bone mass in early adulthood is achieved through appropriate diet and lifestyle, thereby protecting against osteoporosis and risk of bone fracture in later life. Calcium and vitamin D are essential to build adequate bones, but calcium intakes of many population groups do not meet dietary reference values. In addition, changes in dietary patterns are exacerbating the problem, thereby emphasizing the important role of calcium-rich food products. We have designed a calcium-fortified ice cream formulation that is lower in fat than regular ice cream and could provide a useful source of additional dietary calcium. Calcium absorption from two different ice cream formulations was determined in young adults and compared with milk. Subjects/setting Sixteen healthy volunteers (25 to 45 years of age), recruited from the general public of The Netherlands, participated in a randomized, reference-controlled, double-blind cross-over study in which two test products and milk were consumed with a light standard breakfast on three separate occasions: a standard portion of ice cream (60 g) fortified with milk minerals and containing a low level (3%) of butter fat, ice cream (60 g) fortified with milk minerals and containing a typical level (9%) of coconut oil, and reduced-fat milk (1.7% milk fat) (200 mL). Calcium absorption was measured by the dual-label stable isotope technique. Statistical analysis Effects on calcium absorption were evaluated by analysis of variance. Results Fractional absorption of calcium from the 3% butterfat ice cream, 9% coconut oil ice cream, and milk was 26%±8%, 28%±5%, and 31%±9%, respectively, and did not differ significantly (P=0.159). Conclusions Results indicate that calcium bioavailability in the two calcium-fortified ice cream formulations used in this study is as high as milk, indicating that ice cream may be a good vehicle for delivery of calcium. PMID:19394469
Lopez-Heredia, Marco A; Łapa, Agata; Reczyńska, Katarzyna; Pietryga, Krzysztof; Balcaen, Lieve; Mendes, Ana C; Schaubroeck, David; Van Der Voort, Pascal; Dokupil, Agnieszka; Plis, Agnieszka; Stevens, Chris V; Parakhonskiy, Bogdan V; Samal, Sangram Keshari; Vanhaecke, Frank; Chai, Feng; Chronakis, Ioannis S; Blanchemain, Nicolas; Pamuła, Elżbieta; Skirtach, Andre G; Douglas, Timothy E L
2018-04-27
Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO 3 is a widely used bone regeneration material and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone-forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum (GG) hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg-free to Ca-free were compared. Carbonate mineral formed in all sample groups subjected to the Ca:Mg elemental ratio in the carbonate mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO 3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite, decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3-E1 osteoblast-like cells or differentiation after 7 days. This article is protected by copyright. All rights reserved.
[Diet, nutrition and bone health].
Miggiano, G A D; Gagliardi, L
2005-01-01
Nutrition is an important "modifiable" factor in the development and maintenance of bone mass and in the prevention of osteoporosis. The improvement of calcium intake in prepuberal age translates to gain in bone mass and, with genetic factor, to achievement of Peak Bone Mass (PBM), the higher level of bone mass reached at the completion of physiological growth. Individuals with higher PBM achieved in early adulthood will be at lower risk for developing osteoporosis later in life. Achieved the PBM, it is important maintain the bone mass gained and reduce the loss. This is possible adopting a correct behaviour eating associated to regular physical activity and correct life style. The diet is nutritionally balanced with caloric intake adequate to requirement of individual. This is moderate in protein (1 g/kg/die), normal in fat and the carbohydrates provide 55-60% of the caloric intake. A moderate intake of proteins is associated with normal calcium metabolism and presumably does'nt alter bone turnover. An adequate intake of alkali-rich foods may help promote a favorable effect of dietary protein on the skeleton. Lactose intolerance may determinate calcium malabsorption or may decrease calcium intake by elimination of milk and dairy products. Omega3 fatty acids may "down-regulate" pro-inflammatory cytokines and protect against bone loss by decreasing osteoclast activation and bone reabsorption. The diet is characterized by food containing high amount of calcium, potassium, magnesium and low amount of sodium. If it is impossible to reach the requirement with only diet, it is need the supplement of calcium and vitamin D. Other vitamins (Vit. A, C, E, K) and mineral (phosphorus, fluoride, iron, zinc, copper and boron) are required for normal bone metabolism, thus it is need adequate intake of these dietary components. It is advisable reduce ethanol, caffeine, fibers, phytic and ossalic acid intake. The efficacy of phytoestrogens is actually under investigation. Some drugs may interfere with calcium and other nutrients and produce an unfavourable effect on bone health.
de Beer, M; Maree, J P; Liebenberg, L; Doucet, F J
2014-11-01
The production of elemental sulphur and calcium carbonate (CaCO3) from gypsum waste can be achieved by thermally reducing the waste into calcium sulphide (CaS), which is then subjected to a direct aqueous carbonation step for the generation of hydrogen sulphide (H2S) and CaCO3. H2S can subsequently be converted to elemental sulphur via the commercially available chemical catalytic Claus process. This study investigated the carbonation of CaS by examining both the solution chemistry of the process and the properties of the formed carbonated product. CaS was successfully converted into CaCO3; however, the reaction yielded low-grade carbonate products (i.e. <90 mass% as CaCO3) which comprised a mixture of two CaCO3 polymorphs (calcite and vaterite), as well as trace minerals originating from the starting material. These products could replace the Sappi Enstra CaCO3 (69 mass% CaCO3), a by-product from the paper industry which is used in many full-scale AMD neutralisation plants but is becoming insufficient. The insight gained is now also being used to develop and optimize an indirect aqueous CaS carbonation process for the production of high-grade CaCO3 (i.e. >99 mass% as CaCO3) or precipitated calcium carbonate (PCC). Copyright © 2014 Elsevier Ltd. All rights reserved.
Association of Inflammatory, Lipid, and Mineral Markers with Cardiac Calcification in Older Adults
Bortnick, Anna E.; Bartz, Traci M.; Ix, Joachim H.; Chonchol, Michel; Reiner, Alexander; Cushman, Mary; Owens, David; Barasch, Eddy; Siscovick, David S.; Gottdiener, John S.; Kizer, Jorge R.
2016-01-01
Objective Calcification of the aortic valve and adjacent structures involves inflammatory, lipid, and mineral metabolism pathways. We hypothesized that circulating biomarkers reflecting these pathways are associated with cardiac calcification in older adults. Methods We investigated the associations of various biomarkers with valvular and annular calcification in the Cardiovascular Health Study. Of 5888 participants, up to 3585 were eligible after exclusions for missing biomarker, covariate, or echocardiographic data. We evaluated analytes reflecting lipid (lipoprotein [Lp] (a), lipoprotein-associated phospholipase A2 [LpPLA2] mass and activity), inflammatory (interleukin-6, soluble [s] CD14), and mineral metabolism (fetuin-A, fibroblast growth factor [FGF]-23) that were measured within 5 years of echocardiography. The relationships of plasma biomarkers with aortic valve calcium (AVC), aortic annular calcium (AAC) and mitral annular calcium (MAC) were assessed with relative risk (RR) regression. Results Calcification was prevalent: AVC 59%, AAC 45% and MAC 41%. After adjustment, Lp(a), LpPLA2 mass and activity, and sCD14 were positively associated with AVC. RRs for AVC per SD (95% CI) were: Lp(a), 1.051 (1.022–1.081); LpPLA2 mass, 1.036 (1.006–1.066), and activity, 1.037 (1.004–1.071); sCD14, 1.039 (1.005–1.073). FGF-23 was positively associated with MAC, 1.040 (1.004–1.078), and fetuin-A was negatively associated, 0.949 (0.911–0.989). No biomarkers were significantly associated with AAC. Conclusions This study shows novel associations of circulating FGF-23 and fetuin-A with MAC, and LpPLA2 and sCD14 with AVC, confirming that previously reported for Lp(a). Further investigation of lipoprotein and inflammatory pathways may provide added insight into the etiology AVC, while study of phosphate regulation may illuminate the pathogenesis of MAC. PMID:27411840
Vujasinović-Stupar, Nada; Novković, Snezana; Jezdić, Ivana
2009-01-01
Treatment of osteoporosis, in addition to a specific antiresorptive or anabolic treatment, requires supplementation with calcium and vitamin D. Widespread cultivation of pearl shells has made pearls available for commercial use for a very reasonable price. The main chemical compound of pearls from shells Pinctada maxima is calcium-carbonate (CaCO3). Recently developed technologies applied in a micronisation process have provided increased gastrointestinal resorption of calcium, estimated at over 90% of calcium intake. The paper is aimed at monitoring of efficacy and tolerance of six-month bio-calcium supplementation in postmenopausal women with reduced bone mineral density. Group 1 (30 patients) received, three times a day, capsules of pearl powder from shells Pinctada maxima (it is equal to 260 mg of elementary calcium); group II (20 patients) received a daily dose of 500 mg inorganic CaCO3. Both groups received 666 IU of cholecalciferol per day. In all patients, bone mineral density (BMD) of the spine or hip, serum blood and urine levels of Ca, phosphates and alkaline phosphatase, were measured before and after six months of the treatment. Group I/Group II: average age 61.7/61.7 years; beginning of menopause: 48.32 /48 years; menopause duration 13.4/13.7 years; average body mass index 27.2/27 kg/m2. These two groups did not different significantly before supplementation. Six-month supplementation with CaCO3 of the biological origin led to the increase of BMD from 0.901 g/cm2 to 0.948 g/cm2 (p = 0.067), while BMD remained the same in the group supplemented with inorganic CaCO3 Gastrointestinal tolerability of bio-calcium was excellent, without any adverse events. These data could not strongly support the hypothesis of better efficacy of bio-calcium taking into account a small number of patients and a short follow-up period in this pilot study. Tolerance of CaCO3 of the biological origin was excellent and free of any adverse events. The results of laboratory values were within normal range.
Hansen, Karen E.; Johnson, R. Erin; Chambers, Kaitlin R.; Johnson, Michael G.; Lemon, Christina C.; Thuy Vo, Tien Nguyen; Marvdashti, Sheeva
2015-01-01
Importance Experts debate optimal 25(OH)D levels for musculoskeletal health. Objective To compare effects of placebo, low-dose and high-dose vitamin D on one-year changes in total fractional calcium absorption, bone mineral density, Timed-Up-and-Go and 5-sit-to-stand tests and muscle mass in postmenopausal women with vitamin D insufficiency. Design Randomized, double-blind, placebo-controlled, clinical trial conducted from May 2010 to August 2014. Setting Single-center trial conducted in Madison, Wisconsin. Participants 230 postmenopausal women ≤75 years old with baseline 25(OH)D levels 14-27 ng/mL and no osteoporosis. Intervention Three arms included daily white and twice monthly yellow placebo (n=76), daily 800 IU vitamin D3 and twice monthly yellow placebo (n=76), and daily white placebo and twice monthly 50,000 IU vitamin D3 (n=79). The high-dose vitamin D regimen achieved and maintained 25(OH)D levels ≥30 ng/mL. Main Outcome Measures One year change in total fractional calcium absorption using two stable isotopes, bone mineral density and muscle mass using dual energy x-ray absorptiometry, Timed-Up-and-Go and 5-Sit-to-Stand tests, functional status (Health Assessment Questionnaire) and physical activity (Physical Activity Scale for the Elderly), with Benjamini-Hochberg correction of p-values to control the false discovery rate. Results After controlling for baseline absorption, calcium absorption increased 1% (10 mg/day) in the high-dose arm, but decreased by 2% in low-dose (p=0.005 vs. high-dose) and by 1.3% placebo (p=0.03 vs. high-dose) arms. We found no between-arm changes in spine, mean total hip, mean femoral neck or total body bone mineral density, trabecular bone score, muscle mass, 5-sit-to-stand or Timed-Up-and-Go test scores. Likewise, we found no between-arm differences for numbers of falls, number of fallers, physical activity or functional status. Conclusion and Relevance High-dose vitamin D therapy increased calcium absorption, but the effect was small and did not translate into beneficial effects on bone mineral density, muscle function, muscle mass or falls. We found no data to support experts’ recommendations to maintain serum 25(OH)D levels ≥30 ng/mL in postmenopausal women. Instead, we found that low and high-dose vitamin D were equivalent to placebo, in their effects on bone and muscle outcomes in this cohort of postmenopausal women with 25(OH)D levels <30 ng/mL. ClinicalTrials.gov.Identifier:NCT00933244 PMID:26237520
He, Chao; Tian, Chaochao; Li, Gang; Mei, Yahe; Zhang, Quanguo; Jiao, Youzhou
2018-01-01
A coproduction tests of quaternary (Q) phase(6CaO·4Al2O3·MgO·SiO2) -3CaO·3Al2O3·CaSO4 cement clinker and an experimental study on the relationship between the mineral production capability and the physiochemical properties are conducted in a two-stage multiphase reaction test bed with Changguang coal. X-ray diffractometer (XRD) analyses are performed on the coproduction clinker samples. The results demonstrate that, with the reduction in particle sizes of the coal powder and the additives and expanded screening level differences between them, both the proportion of Q phase and the mass of 3CaO·3Al2O3·CaSO4 in the clinker increase accordingly. When mixed coal powder particles are prepared through reducing particle sizes and expanding screening level differences between coal powder and additives, the additives CaO and MgO are more likely to be enclosed by coal powder to form globular polymerized particles. In addition, this preparation aids in polymerization and promotes even distribution of CaO, MgO and coal minerals, thus facilitating clinker mineral formation reactions of inorganic substances in the mixed coal powder. Target minerals, such as 2CaO·SiO2 and Q phase, are found in both industrial high-calcium limestone and low-calcium limestone coproduction clinker samples. A diffraction peak of free CaO is also evident in both samples. Compared with a coproduction clinker sample of high-calcium limestone, that of low-calcium limestone exhibits higher diffraction peaks for 2CaO·SiO2 and Q phase. With the current state of the art, it is not yet the optimum choice to substitute CaCO3 for CaO in Q-phase cement clinker coproduction. Before the technology matures and gains practical application, further study on the form and the mixing process of calcium-based additives for cement clinker coproduction will be required.
Tian, Chaochao; Li, Gang; Mei, Yahe; Zhang, Quanguo; Jiao, Youzhou
2018-01-01
A coproduction tests of quaternary (Q) phase(6CaO·4Al2O3·MgO·SiO2) -3CaO·3Al2O3·CaSO4 cement clinker and an experimental study on the relationship between the mineral production capability and the physiochemical properties are conducted in a two-stage multiphase reaction test bed with Changguang coal. X-ray diffractometer (XRD) analyses are performed on the coproduction clinker samples. The results demonstrate that, with the reduction in particle sizes of the coal powder and the additives and expanded screening level differences between them, both the proportion of Q phase and the mass of 3CaO·3Al2O3·CaSO4 in the clinker increase accordingly. When mixed coal powder particles are prepared through reducing particle sizes and expanding screening level differences between coal powder and additives, the additives CaO and MgO are more likely to be enclosed by coal powder to form globular polymerized particles. In addition, this preparation aids in polymerization and promotes even distribution of CaO, MgO and coal minerals, thus facilitating clinker mineral formation reactions of inorganic substances in the mixed coal powder. Target minerals, such as 2CaO·SiO2 and Q phase, are found in both industrial high-calcium limestone and low-calcium limestone coproduction clinker samples. A diffraction peak of free CaO is also evident in both samples. Compared with a coproduction clinker sample of high-calcium limestone, that of low-calcium limestone exhibits higher diffraction peaks for 2CaO·SiO2 and Q phase. With the current state of the art, it is not yet the optimum choice to substitute CaCO3 for CaO in Q-phase cement clinker coproduction. Before the technology matures and gains practical application, further study on the form and the mixing process of calcium-based additives for cement clinker coproduction will be required. PMID:29634732
Dairy food intake, peripheral bone structure, and muscle mass in elderly ambulatory women.
Radavelli-Bagatini, Simone; Zhu, Kun; Lewis, Joshua R; Prince, Richard L
2014-07-01
Previous studies suggest that dairy intake may be associated with reduced bone and muscle loss with aging, but there are limited data in the very old. We evaluated the association between intake of dairy foods and peripheral bone structure and muscle mass in 564 elderly women aged 80 to 92 (mean 84.7) years, who were participants of the Calcium Intake Fracture Outcome Study/CAIFOS Aged Extension Study (CAIFOS/CARES) cohort and attended the 10-year follow-up. Assessments included dairy consumption (milk, yogurt, and cheese) by a validated food frequency questionnaire, 15% tibia bone mass, area and volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT), and appendicular bone and skeletal muscle mass by dual-energy X-ray absorptiometry (DXA). Women were categorized according to tertiles of dairy intake: first tertile (≤ 1.5 servings/d), second tertile (1.5 to 2.2 servings/d) and third tertile (≥ 2.2 servings/d). Controlling for confounding factors, pQCT assessment at the 15% tibia showed that compared with those in the first tertile of dairy intake, women in the third tertile had 5.7% greater total bone mass (p = 0.005), principally because of an increase in cortical and subcortical bone mass (5.9%, p = 0.050), resulting in a 6.2% increase in total vBMD (p = 0.013). Trabecular but not cortical and subcortical vBMD was also higher (7.8%, p = 0.044). DXA assessment showed that women in the third tertile of dairy intake had greater appendicular bone mass (7.1%, p = 0.007) and skeletal muscle mass (3.3%, p = 0.014) compared with tertile 1. The associations with bone measures were dependent on dairy protein and calcium intakes, whereas the association with appendicular muscle mass was not totally dependent on dairy protein intake. Our results suggest a positive association of dairy intake with appendicular bone mineralization and muscle mass in elderly women. Because many fractures in this age group are of the appendicular skeleton often associated with falls, dairy intake may be a modifiable lifestyle factor contributing to healthy aging. © 2014 American Society for Bone and Mineral Research.
Calcium Isotope Systematics During Development of the Domestic Chicken (Gallus gallus)
NASA Astrophysics Data System (ADS)
Wheatley, P. V.
2003-12-01
Calcium isotope distributions have been recognized as showing systematic and predictable fractionation in nature. However, most of the observed calcium isotope fractionation to date is due to biological processes. The presence of abundant amounts of calcium in mineralized tissues makes the isotopic system of calcium particularly valuable in biological and paleobiological questions involving biomineralization. In order to apply calcium isotope systematics to paleobiological questions the changes in the calcium isotope signatures of mineralized tissue in modern animals should be studied. My study observed the domestic chicken (Gallus gallus) through embryologic ontogeny. This was accomplished by obtaining fertilized eggs staged in a growth series from day 12 to day 20. The eggs were dissected and shell, embryonic bone, albumen, and yolk were analyzed in order to characterize the calcium isotopic composition of the individual components over the course of the growth series. Several systematic changes in the isotopic signatures of various tissues were observed during the course of the development of the embryos. In general, mineralization in biological systems preferentially partitions the lighter isotopes of calcium into hard parts. As a result of this fractionation during mineralization, partitioning of light isotopes of calcium into the mineralized tissues may result in residual tissues being enriched in the heavier isotopes as ontogeny progresses. Better understanding of the behavior of calcium in modern biological systems will improve its application to fossils and expand the number of paleobiological and evolutionary questions that can be addressed using calcium isotopic data.
Feng, Xin; Lyu, Ying; Wu, Zhenghao; Fang, Yuehui; Xu, Hao; Zhao, Pengling; Xu, Yajun; Feng, Haotian
2014-04-01
Optimizing peak bone mass in early life is one of key preventive strategies against osteoporosis. Fructus ligustri lucidi (FLL), the fruit of Ligustrum lucidum Ait., is a commonly prescribed herb in many kidney-tonifying traditional Chinese medicinal formulas to alleviate osteoporosis. Previously, FLL extracts have been shown to have osteoprotective effect in aged or ovariectomized rats. In the present study, we investigated the effects of FLL ethanol extract on bone mineral density (BMD) and mechanical properties in growing male rats and explored the underlying mechanisms. Male weaning Sprague-Dawley rats were randomized into four groups and orally administrated for 4 months an AIN-93G formula-based diet supplementing with different doses of FLL ethanol extract (0.40, 0.65, and 0.90 %) or vehicle control, respectively. Then calcium balance, serum level of Ca, P, 25(OH)2D3, 1,25(OH)2D3, osteocalcin (OCN), C-terminal telopeptide of type I collagen (CTX-I), and parathyroid hormone, bone microarchitecture, and calcium absorption-related genes expression in duodenum and kidney were analyzed. The results demonstrated that FLL ethanol extract increased BMD of growing rats and improved their bone microarchitecture and mechanical properties. FLL ethanol extract altered bone turnover, as evidenced by increasing a bone formation maker, OCN, and decreasing a bone resorption maker, CTX-I. Intriguingly, both Ca absorption and Ca retention rate were elevated by FLL ethanol extract treatment, possibly through the mechanisms of up-regulating the transcriptions of calcitropic genes in kidney (1α-hydroxylase) and duodenum (vitamin D receptor, calcium transporter calbindin-D9k, and transient receptor potential vanilloid 6). In conclusion, FLL ethanol extract increased bone mass gain and improved bone properties via modulating bone turnover and up-regulating calcium absorption-related gene expression in kidney and duodenum, which could then activate 1,25(OH)2D3-dependent calcium transport in male growing rats.
Characterisation of Bone Beneficial Components from Australian Wallaby Bone
Lao, Weiguo; Jin, Xingliang; Tan, Yi; Xiao, Linda; Padula, Matthew P.; Bishop, David P.; Reedy, Brian; Ong, Madeleine; Kamal, Mohammad A.; Qu, Xianqin
2016-01-01
Background: Osteoporosis is a condition in which the bones become brittle, increasing the risk of fractures. Complementary medicines have traditionally used animal bones for managing bone disorders, such as osteoporosis. This study aimed to discover new natural products for these types of conditions by determining mineral and protein content of bone extracts derived from the Australian wallaby. Methods: Inductively coupled plasma-mass spectrometry and Fourier transform infrared spectroscopic analysis were used for mineral tests, proteome analysis was using LC/MS/MS and the effects of wallaby bone extracts (WBE)s on calcium deposition and alkaline phosphatase activity were evaluated in osteogenic cells derived from adipose tissue-derived stem cells (ADSCs). Results: Concentrations of calcium and phosphorus were 26.21% and 14.72% in WBE respectively. Additionally, minerals found were wide in variety and high in concentration, while heavy metal concentrations of aluminium, iron, zinc and other elements were at safe levels for human consumption. Proteome analysis showed that extracts contained high amounts of bone remodelling proteins, such as osteomodulin, osteopontin and osteoglycin. Furthermore, in vitro evaluation of WBEs showed increased deposition of calcium in osteoblasts with enhanced alkaline phosphatase activity in differentiated adipose-derived stem cells. Conclusion: Our results demonstrate that wallaby bone extracts possess proteins and minerals beneficial for bone metabolism. WBEs may therefore be used for developing natural products for conditions such as osteoporosis and further investigation to understand biomolecular mechanism by which WBEs prevent osteoporosis is warranted. PMID:28930133
Vatanparast, Hassanali; Baxter-Jones, Adam; Faulkner, Robert A; Bailey, Donald A; Whiting, Susan J
2005-09-01
Nutrition is an important modifiable factor in the development of bone mass during adolescence. Recent studies of children and adolescents examined the effects of foods such as milk products and fruit and vegetables on bone growth; however, few studies included both boys and girls. The purpose was to ascertain the role of consumption of milk products and vegetables and fruit in the accrual of total-body bone mineral content (TBBMC) in boys and girls from childhood to late adolescence. Seven-year longitudinal data were obtained from 85 boys and 67 girls aged 8-20 y. Biological maturity was defined by the number of years from the age at peak height velocity. Dietary intake was assessed by serial 24-h recalls. Anthropometric measurements and physical activity were assessed every 6 mo. TBBMC assessed with dual-energy X-ray absorptiometry in the fall of each year was the indicator of bone mass. Most boys (87.8%) met Canadian recommendations for milk product intake. Few subjects (<30%) consumed vegetables and fruit in recommended amounts. Using a multilevel modeling statistical approach containing important biological and environmental factors, we found that vegetable and fruit intakes, calcium intake, and physical activity were significant independent environmental predictors of TBBMC in boys but not in girls. In addition to adequate dietary calcium intake, appropriate intakes of vegetables and fruit have a beneficial effect on TBBMC in boys aged 8-20 y. Underreporting of dietary intake by girls may explain why this effect was not apparent in girls.
Ashouri, Elham; Meimandi, Elham Mahmoodi; Saki, Forough; Dabbaghmanesh, Mohammad Hossein; Omrani, Gholamhossein Ranjbar; Bakhshayeshkaram, Marzieh
2015-11-01
Failure to achieve optimal bone mass in childhood is the primary cause of decreased adult bone mineral density (BMD) and increased bone fragility in later life. Activating and inactivating LRP5 gene mutations has been associated with extreme bone-related phenotypes. Our aim was to investigate the role of LRP5 polymorphism on BMD, mineral biochemical parameters, and body composition in Iranian children. This cross-sectional study was performed on 9-18 years old children (125 boys, 137 girls). The serum level of calcium, phosphorous, alkaline phosphatase, and vitamin D parameters were checked. The body composition and BMD variables were measured by the Hologic system DXA. The rs566442 (V1119V) coding polymorphism in exon 15 of LRP5 was performed using PCR-RFLP method. Linear regression analysis, with adjustment for age, gender, body size parameters, and pubertal status was used to determine the association between LRP5 polymorphism (rs556442) and bone and body composition parameters. The allele frequency of the rs566442 gene was 35.5 % A and 63.9 % G. Our study revealed that LRP5 (rs556442) has not any significant influence on serum calcium, phosphorus, 25OHvitD, and serum alkaline phosphatase (P > 0.05). Total lean mass was greater in GG genotype (P = 0.028). Total body less head area (P = 0.044), spine BMD (P = 0.04), and total femoral BMC (P = 0.049) were lower in AG heterozygote genotype. This study show LRP5 polymorphism may associate with body composition and BMD in Iranian children. However, further investigations should be done to evaluate the role of other polymorphism.
Cuticular Biominerals of the Terrestrial Crustacean Oniscus asellus (Isopoda, Linnaeus 1758)
NASA Astrophysics Data System (ADS)
Mergelsberg, S. T.; Mukhopadhyay, B.; Dove, P. M.
2013-12-01
Biomineralization is a phenomenon observed in many eukaryotic organisms and evidence suggests this process began relatively early in the evolution of multicellular life (Marin F et al. 1996). Crustaceans form a large fraction of all eukaryotic biomineralizers by incorporating calcium carbonate (CaCO3) into their cuticle. Terrestrial species are challenged in their production of CaCO3 by the absence of calcium-rich waters. To cope with this limitation, the terrestrial crustacean Oniscus asellus recycles up to 80% (Auzou G 1953) of its total calcium during the molting process. This feat is accomplished by separate molting of the front and back cuticle, with temporary storage of the calcium carbonate as amorphous calcium carbonate (ACC) in the front half (Ziegler A 1997). These processes infer a highly efficient and regulated mechanism for biomineralization that is most likely orchestrated by a myriad of proteins (Ziegler A et al. 2012). Until recently, investigations of biomineralization were largely directed toward understanding morphology and large-scale chemistry of the minerals, ignoring the mechanistic roles of biomacromolecules in mineralization processes. More recent work suggests a high involvement of these compounds on the formation of biominerals and, in some cases, the specific polymorphs thereof (Keene EC et al. 2010). This study focuses on identifying the components of the biological mineralization matrix at each stage of the process. Using chemical demineralization of the stored ACC, all biomacromolecules can be separated and purified for subsequent analysis by MALDI-TOF mass spectrometry. To link the localized biochemistry more intimately to the polymorph of calcium carbonate that forms in the animal, the inorganic phase (';the mineral') will be monitored at each life stage using XRD and TEM. This analysis will reveal the organic components of a very precise biomineralization mechanism and may shed insight on its evolutionary origin. References: Marin F, Westbroek P et al., 1996, Proc Nat Acad Sci 93:1554-1559 Auzou G, 1953, L Ann Sci Nat 15:71-98 Ziegler A, 1997, Zoomorphology 117:181-187 Ziegler A et al., 2012, Cryst Growth Des 12:646-655 Keene EC et al., 2010, Cryst Growth Des 10:1383-1389
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zanzi, I.; Roginsky, M.S.; Ellis, K.J.
1976-01-01
The evaluation of diffuse osteoporosis in patients with rheumatoid arthritis (RA) remains controversial. An important associated problem is the compounded effect of osteopenia secondary to chronic corticosteroid treatment. Photon-absorptiometric techniques have been utilized for measurements of selected sites of the skeleton, such as the distal femur and the distal radius. The development of the technique of in-vivo total body neutron activation analysis (TBNAA) along with whole body counting, has made possible the direct measurement of skeletal mass (total body calcium, TBCa). The TBCa and radial bone mineral content (BMC) were evaluated in 19 Caucassian women with R.A., with and withoutmore » a history of corticosteroid treatment. (auth)« less
NASA Astrophysics Data System (ADS)
Nerdy
2018-01-01
Vegetables from the cabbage family vegetables consumed by many people, which is known healthful, by eaten raw, boiled, or cooked (stir fry or soup). Vegetables like broccoli and cauliflower contain vitamins, minerals, and fiber. This study aims to determine the decrease percentage of sodium, potassium, magnesium, and calcium minerals level caused by boiled broccoli and cauliflower by atomic absorption spectrometry. Boiled broccoli and cauliflower prepared by given boiled treatment in boiling water for 3 minutes. Fresh and boiled broccoli and cauliflower carried out dry destruction, followed by quantitative analysis of sodium, potassium, magnesium, and calcium minerals respectively at a wavelength of 589.0 nm; 766.5 nm; 285.2 nm; and 422.7 nm, using atomic absorption spectrometry methods. After the determination of the sodium, potassium, magnesium, and calcium minerals level followed by validation of analytical methods with accuracy, precision, linearity, range, limit of detection (LOD), and limit of quantitation (LOQ) parameters. Research results show a decrease in the sodium, potassium, magnesium, and calcium minerals level in boiled broccoli and cauliflower compared with fresh broccoli and cauliflower. Validation of analytical methods gives results that spectrometry methods used for determining sodium, potassium, magnesium, and calcium minerals level are valid. It concluded that the boiled gives the effect of decreasing the minerals level significantly in broccoli and cauliflower.
Calcium and bone health in children: a review.
Stallings, V A
1997-01-01
The recent national survey shows that dietary calcium intake is variable in children and adolescents, with about half consuming less than the intake recommended by the Recommended Dietary Allowances or the National Institutes of Health Consensus Panel on Optimal Calcium Intake. Osteoporosis is a major disease in adults, resulting in 1.5 million fractures and over $10 billion in medical expenditures annually. Osteoporosis is of growing interest in the research, public health, and health consumer-lay communities and to the many primary care and specialty physicians and other health care professionals who work directly with patients with osteoporosis. Treatment of osteoporosis to prevent fracture is improving with newly introduced medications and approaches, but it is not as effective as needed. Effective prevention strategies are critical to decreasing the morbidity and mortality of the disease. Peak bone mass, obtained during childhood and adolescent growth, is one of the major determinants for the risk of developing osteoporosis and fracture. Genetic potential, gender, ethnic origins, nutritional factors such as calcium and vitamin D intake, growth patterns, and physical activity influence the accretion of bone mineral during childhood and determine the peak bone mass. Randomized, placebo-controlled intervention trials conducted in healthy children who are consuming amounts of dietary calcium in accordance with the US recommendations show that bone mass can be increased by calcium supplementation. Retrospective studies in adults suggest that childhood calcium intake is associated with risk of later osteoporosis and fracture. In addition, common childhood clinical conditions, such as low calcium intake related to lactose intolerance or the use of glucocorticoid medications for chronic illness, are risk factors for the development of osteoporosis in childhood, not just in adulthood. An approach for physicians and other pediatric care providers for screening children for low dietary calcium intake, low bone density, and other osteoporosis risk factors using dual-energy X-ray absorptiometry and the use of calcium supplementation in clinical care are presented.
Rodríguez-Navarro, Alejandro B; Marie, Pauline; Nys, Yves; Hincke, Maxwell T; Gautron, Joel
2015-06-01
Avian eggshell mineralization is the fastest biogenic calcification process known in nature. How this is achieved while producing a highly crystalline material composed of large calcite columnar single crystals remains largely unknown. Here we report that eggshell mineral originates from the accumulation of flat disk-shaped amorphous calcium carbonate (ACC) particles on specific organic sites on the eggshell membrane, which are rich in proteins and sulfated proteoglycans. These structures known as mammillary cores promote the nucleation and stabilization of a amorphous calcium carbonate with calcitic short range order which predetermine the calcite composition of the mature eggshell. The amorphous nature of the precursor phase was confirmed by the diffuse scattering of X-rays and electrons. The nascent calcitic short-range order of this transient mineral phase was revealed by infrared spectroscopy and HRTEM. The ACC mineral deposited around the mammillary core sites progressively transforms directly into calcite crystals without the occurrence of any intermediate phase. Ionic speciation data suggest that the uterine fluid is equilibrated with amorphous calcium carbonate, throughout the duration of eggshell mineralization process, supporting that this mineral phase is constantly forming at the shell mineralization front. On the other hand, the transient amorphous calcium carbonate mineral deposits, as well as the calcite crystals into which they are converted, form by the ordered aggregation of nanoparticles that support the rapid mineralization of the eggshell. The results of this study alter our current understanding of avian eggshell calcification and provide new insights into the genesis and formation of calcium carbonate biominerals in vertebrates. Copyright © 2015 Elsevier Inc. All rights reserved.
Mitri, Zahi; Tangpricha, Vin
2012-01-01
We report the case of a 30-year-old African-American male with osteopetrosis and hypophosphatemia, presenting with diffuse myalgias. Laboratory evaluation performed revealed a low serum phosphorus level with urinary phosphate wasting, low calcium, and 25-hydroxyvitamin D concentrations, as well as elevated alkaline phosphatase. Skull and pelvic radiographs revealed high bone density consistent with high bone mass found on bone mineral density reports. PHEX gene mutation analysis was negative. Patient was started on calcium and phosphorus replacement, and he clinically improved. This paper will review the different subtypes of osteopetrosis, and the evaluation of hypophosphatemia.
Space medicine considerations: Skeletal and calcium homeostasis
NASA Technical Reports Server (NTRS)
Schneider, Victor B.
1989-01-01
Based on the information obtained from space missions, particularly Skylab and the longer Salyut missions, it is clear that bone and mineral metabolism is substantially altered during space flight. Calcium balance becomes increasingly more negative throughout the flight, and the bone mineral content of the os calcis declines. The major health hazards associated with skeletal changes include the signs and symptoms of hypercalcemia with rapid bone turnover, the risk of kidney stones because of hypercalciuria, the lengthy recovery of lost bone mass after flight, the possibility of irreversible bone loss (particularly the trabecular bone), the possible effects of metastated calcification in the soft tissues, and the possible increase in fracture potential. For these reasons, major efforts need to be directed toward elucidating the fundamental mechanisms by which bone is lost in space and developing more effective countermeasures to prevent both short-term and long-term complications.
Calcium metabolism in health and disease.
Peacock, Munro
2010-01-01
This brief review focuses on calcium balance and homeostasis and their relationship to dietary calcium intake and calcium supplementation in healthy subjects and patients with chronic kidney disease and mineral bone disorders (CKD-MBD). Calcium balance refers to the state of the calcium body stores, primarily in bone, which are largely a function of dietary intake, intestinal absorption, renal excretion, and bone remodeling. Bone calcium balance can be positive, neutral, or negative, depending on a number of factors, including growth, aging, and acquired or inherited disorders. Calcium homeostasis refers to the hormonal regulation of serum ionized calcium by parathyroid hormone, 1,25-dihydroxyvitamin D, and serum ionized calcium itself, which together regulate calcium transport at the gut, kidney, and bone. Hypercalcemia and hypocalcemia indicate serious disruption of calcium homeostasis but do not reflect calcium balance on their own. Calcium balance studies have determined the dietary and supplemental calcium requirements needed to optimize bone mass in healthy subjects. However, similar studies are needed in CKD-MBD, which disrupts both calcium balance and homeostasis, because these data in healthy subjects may not be generalizable to this patient group. Importantly, increasing evidence suggests that calcium supplementation may enhance soft tissue calcification and cardiovascular disease in CKD-MBD. Further research is needed to elucidate the risks and mechanisms of soft tissue calcification with calcium supplementation in both healthy subjects and CKD-MBD patients.
Calcium Intake, Major Dietary Sources and Bone Health Indicators in Iranian Primary School Children.
Omidvar, Nasrin; Neyestani, Tirang-Reza; Hajifaraji, Majid; Eshraghian, Mohammad-Reza; Rezazadeh, Arezoo; Armin, Saloumeh; Haidari, Homa; Zowghi, Telma
2015-02-01
Adequate calcium intake may have a crucial role with regards to prevention of many chronic diseases, including hypertension, hypercholesterolemia, different types of cancer, obesity and osteoporosis. In children, sufficient calcium intake is especially important to support the accelerated growth spurt during the preteen and teenage years and to increase bone mineral mass to lay the foundation for older age. This study aimed to assess daily calcium intake in school-age children to ensure whether they fulfill the FGP dairy serving recommendations, the recommended levels of daily calcium intake and to assess the relationship between dietary calcium intake and major bone health indicators. A total of 501 Iranian school-age children were randomly selected. Calcium intake was assessed using a semi-quantitative food frequency questionnaire. Bone health indicators were also assessed. Dairy products contributed to 69.3% of the total calcium intake of the children. Daily adequate intake of calcium was achieved by 17.8% of children. Only 29.8% met the Food guide pyramid recommendations for dairy intake. Dietary calcium intake was not significantly correlated with serum calcium and other selected biochemical indicators of bone health. The need for planning appropriate nutrition strategies for overcoming inadequate calcium intake in school age children in the city of Tehran is inevitable.
NASA Technical Reports Server (NTRS)
Makuch, Lauren A.
2004-01-01
Humans reach peak bone mass at age 30. After this point, we lose 1 to 2 percent of bone mass each decade. In the microgravity environment of space, astronauts lose bone mass at an accelerated rate of 1 to 2 percent each month. When astronauts travel to Mars, they may be in space for as long as 3 years. During this time, they may lose about half of their bone mass from weight-bearing bones. This loss may be irreversible. The drastic loss in bone that astronauts experience in space makes them much more vulnerable to fractures. In addition, the corresponding removal of calcium from bone results in higher levels of calcium in the blood, which increases the risk of developing kidney stones. Currently, studies are being conducted which investigate factors governing bone adaptation and mechanotransduction. Bone is constantly adapting in response to mechanical stimuli. Increased mechanical loading stimulates bone formation and suppresses bone resorption. Reduction in mechanical loading caused by bedrest, disuse, or microgravity results in decreased bone formation and possibly increased bone resorption. Osteoblasts and osteoclasts are the two main cell types that participate in bone remodeling. Osteoblasts are anabolic (bone-forming) cells and osteoclasts are catabolic (bone-resorbing) cells. In microgravity, the activity of osteoblasts slows down and the activity of osteoclasts may speed up, causing a loss of bone density. Mechanotransduction, the molecular mechanism by which mechanical stimuli are converted to biochemical signals, is not yet understood. Exposure of cells to fluid flow imposes a shear stress on the cells. Several studies have shown that the shear stress that results from fluid flow induces a cellular response similar to that induced by mechanical loading. Thus, fluid flow can be used as an in vitro model to simulate the mechanical stress that bone cells experience in vivo. Previous in vitro studies have shown that fluid flow induces several responses in osteoblasts, including increased proliferation, osteoblastic differentiation, alkaline phosphatase activity, and production of nitric oxide, prostaglandins, and osteopontin. Several proteins have been implicated in osteoblastic mechanotransduction including Bone Morphogenetic Protein-2 (BMP-2), parathyroid hormone, 1,25-dihydroxyvitamin D3 receptor, osteopontin (OPN), osteoprotegerin (OPG), and alkaline phosphatase (AP). We will characterize relative levels of each protein in mineralizing or non-mineralizing MC3T3 osteoblastic cells that have been exposed to fluid flow compared to non-fluid flow using immunofluorescent staining and two- photon laser microscopy as well as western blotting. Because calcium-mediated pathways are important in osteoblastic signaling, we will transfect MC3T3 cells with cameleon probes for Ca2+ containing YFP and CFP. Results will be analyzed using FRET/FLIM to study differential release of intracellular Ca(2+) in response to fluid flow and conditions inducing matrix mineralization. In addition, we plan to conduct several microarray experiments to determine differential gene expression in MC3T3 cells in response to fluid flow and conditions inducing mineralization.
USDA-ARS?s Scientific Manuscript database
The relative contributions of calcium and vitamin D to calcium metabolism and bone mineral density (BMD) have been examined previously, but not in a population with very low calcium intake. To determine the relative importance of dietary calcium intake and serum 25-hydroxyvitamin D [25(OH)D] concent...
Geochemistry of spring water, southeastern Uinta Basin, Utah and Colorado
Kimball, Briant A.
1981-01-01
The chemical quality of water in the southeastern Uinta Basin, Utah and Colorado, is important to the future development of the abundant oil-shale resources of the area. This report examines the observed changes in chemistry as water circulates in both shallow and deep ground-water systems. Mass-balance and mass- transfer calculations are used to define reactions that simulate the observed water chemistry in the mixed sandstone, siltstone, and carbonate lithology of the Green River Formation of Tertiary age.The mass-transfer calculations determine a reaction path particular to this system. The early dominance of calcite dissolution produces a calcium carbonate water. After calcite saturation, deeper circulation and further rock-water interaction cause the reprecipitation of calcite, the dissolution of dolomite and plagioclase, and the oxidation of pyrite; all combining to produce a calcium magnesium sodium bicarbonate sulfate water. The calculations suggest that silica concentrations are controlled by a kaolinite-Ca-montmorillonite phase boundary. Close agreement of mineral-saturation indices calculated by both an aqueous-equilibrium model and the mass-transfer model support the selection of reactions from the mass-transfer calculations.
Fourier transform Raman spectroscopy of synthetic and biological calcium phosphates.
Sauer, G R; Zunic, W B; Durig, J R; Wuthier, R E
1994-05-01
Fourier-transform (FT) Raman spectroscopy was used to characterize the organic and mineral components of biological and synthetic calcium phosphate minerals. Raman spectroscopy provides information on biological minerals that is complimentary to more widely used infrared methodologies as some infrared-inactive vibrational modes are Raman-active. The application of FT-Raman technology has, for the first time, enabled the problems of high sample fluorescence and low signal-to-noise that are inherent in calcified tissues to be overcome. Raman spectra of calcium phosphates are dominated by a very strong band near 960 cm-1 that arises from the symmetric stretching mode (v1) of the phosphate group. Other Raman-active phosphate vibrational bands are seen at approximately 1075 (v3), 590 (v4), and 435 cm-1 (v2). Minerals containing acidic phosphate groups show additional vibrational modes. The different calcium phosphate mineral phases can be distinguished from one another by the relative positions and shapes of these bands in the Raman spectra. FT-Raman spectra of nascent, nonmineralized matrix vesicles (MV) show a distinct absence of the phosphate v1 band even though these structures are rich in calcium and phosphate. Similar results were seen with milk casein and synthetic Ca-phosphatidyl-serine-PO4 complexes. Hence, the phosphate and/or acidic phosphate ions in these noncrystalline biological calcium phosphates is in a molecular environment that differs from that in synthetic amorphous calcium phosphate. In MV, the first distinct mineral phase to form contained acidic phosphate bands similar to those seen in octacalcium phosphate. The mineral phase present in fully mineralized MV was much more apatitic, resembling that found in bones and teeth.(ABSTRACT TRUNCATED AT 250 WORDS)
Dietary protein and skeletal health: a review of recent human research.
Kerstetter, Jane E; Kenny, Anne M; Insogna, Karl L
2011-02-01
Both dietary calcium and vitamin D are undoubtedly beneficial to skeletal health. In contrast, despite intense investigation, the impact of dietary protein on calcium metabolism and bone balance remains controversial. A widely held view is that high intakes of animal protein result in increased bone resorption, reduced bone mineral density, and increased fractures because of its ability to generate a high fixed metabolic acid load. The purpose of this review is to present the recent or most important epidemiological and clinical trials in humans that evaluated dietary protein's impact on skeletal health. Many epidemiological studies have found a significant positive relationship between protein intake and bone mass or density. Similarly, isotopic studies in humans have also demonstrated greater calcium retention and absorption by individuals consuming high-protein diets, particularly when the calcium content of the diet was limiting. High-protein intake may positively impact bone health by several mechanisms, including calcium absorption, stimulation of the secretion of insulin-like growth factor-1, and enhancement of lean body mass. The concept that an increase in dietary protein induces a large enough shift in systemic pH to increase osteoclastic bone resorption seems untenable. Recent epidemiological, isotopic and meta-analysis studies suggest that dietary protein works synergistically with calcium to improve calcium retention and bone metabolism. The recommendation to intentionally restrict dietary protein to improve bone health is unwarranted, and potentially even dangerous to those individuals who consume inadequate protein.
Barger-Lux, M Janet; Davies, K Michael; Heaney, Robert P
2005-10-01
In earlier observational work, the dietary calcium:protein ratio was directly related to bone accrual in healthy postadolescent women. In this study, we sought to test the hypothesis that augmented calcium intake would increase postadolescent skeletal consolidation, using a double-blind, randomized, placebo-controlled design. We recruited 152 healthy young women (age 23.1 +/- 2.7 y, BMI 22.5 +/- 3.0 kg/m2); their usual diets, as assessed by 7-d food diaries, were low in calcium (605 +/- 181 mg/d; 15.1 +/- 4.5 mmol/d) and in the calcium:protein ratio (10.1 +/- 2.0 mg/g). The subjects were randomly assigned to supplemental calcium [500 mg calcium (12.5 mmol) as the carbonate, 3 times/d, with meals] or placebo capsules identical in appearance; all participants also took a daily multivitamin, and they were followed for up to 36 mo with bone densitometry (dual energy X-ray absorptiometry; DXA) at 6-mo intervals. A total of 121 subjects remained in the study for at least 12 mo (median time in the study, 35 mo), with a mean compliance level (observed/expected tablet consumption) of 87.7%. DXA data for these 121 subjects indicated modest but significant mean rates of increase (i.e., 0.24 to 1.10%/y) in bone mineral content (BMC; total body, total hip, and lumbar spine) and in lumbar spine bone mineral density (BMD) but no change in total hip BMD. None of these rates of change differed by group, i.e., calcium supplementation did not have any measurable effect on bone mass accrual. By midstudy, the calcium content of the subjects' usual diets for both groups had risen by approximately 15%. The combined effect of improved intakes of dietary calcium and the small amount of calcium added by the multivitamin tablets resulted in a mean calcium intake for the control group > 800 mg (20 mmol)/d, possibly at or near the threshold beyond which additional calcium has no further effect on bone accrual.
IMPACT OF DEFICIENT NUTRITION IN BONE MASS AFTER BARIATRIC SURGERY.
Costa, Tatiana Munhoz da Rocha Lemos; Paganoto, Mariana; Radominski, Rosana Bento; Borba, Victoria Zeghbi Cochenski
2016-03-01
Essential nutrients are considered for the prevention of the bone loss that occurs after bariatric surgery. Evaluate nutrients involved in bone metabolism, and relate to serum concentrations of calcium, vitamin D, and parathyroid hormone, and the use of supplements and sun exposure on the bone mass of patients who had undergone gastric bypass surgery. An observational study, with patients who had undergone the surgery 12 or more months previously, operated group (OG), compared to a control group (CG). Were included 56 in OG and 27 in the CG. The mean age was 36.4±8.5 years. The individuals in the OG, compared to CG, consumed inadequate amounts of protein and daily calcium. The OG had a higher prevalence of low sun exposure, lower levels of 25OH Vitamin D (21.3±10.9 vs. 32.1±11.8 ng/dl), and increased serum levels of parathyroid hormone (68.1±32.9 vs. 39.9±11.9 pg/ml, p<0.001). Secondary hyperparathyroidism was present only in the OG (41.7%). The mean lumbar spine bone mineral density was lower in the OG. Four individuals from the OG had low bone mineral density for chronological age, and no one from the CG. The dietary components that affect bone mass in patients undergoing bariatric surgery were inadequate. The supplementation was insufficient and the sun exposure was low. These changes were accompanied by secondary hyperparathyroidism and a high prevalence of low bone mass in lumbar spine in these subjects.
Experiment 305: Pathophysiology of Mineral Loss During Space Flight
NASA Technical Reports Server (NTRS)
Arnaud, Claude D.; Cann, Christopher E.
1995-01-01
The objective of this SLS-2 experiment was to determine the pathophysiology of mineral loss during space flight. This was to be accomplished by (1) determining the concentrations of blood minerals and of calciotropic hormones (parathyroid hormone-PTH, vitamin D metabolites) before, during, and after a 14 day shuttle flight, and (2) determining, by calcium kinetic analysis (using stable calcium isotopes), the influence of space flight on intestinal calcium absorption .
The role of intracellular calcium phosphate in osteoblast-mediated bone apatite formation
Boonrungsiman, Suwimon; Gentleman, Eileen; Carzaniga, Raffaella; Evans, Nicholas D.; McComb, David W.; Porter, Alexandra E.; Stevens, Molly M.
2012-01-01
Mineralization is a ubiquitous process in the animal kingdom and is fundamental to human development and health. Dysfunctional or aberrant mineralization leads to a variety of medical problems, and so an understanding of these processes is essential to their mitigation. Osteoblasts create the nano-composite structure of bone by secreting a collagenous extracellular matrix (ECM) on which apatite crystals subsequently form. However, despite their requisite function in building bone and decades of observations describing intracellular calcium phosphate, the precise role osteoblasts play in mediating bone apatite formation remains largely unknown. To better understand the relationship between intracellular and extracellular mineralization, we combined a sample-preparation method that simultaneously preserved mineral, ions, and ECM with nano-analytical electron microscopy techniques to examine osteoblasts in an in vitro model of bone formation. We identified calcium phosphate both within osteoblast mitochondrial granules and intracellular vesicles that transported material to the ECM. Moreover, we observed calcium-containing vesicles conjoining mitochondria, which also contained calcium, suggesting a storage and transport mechanism. Our observations further highlight the important relationship between intracellular calcium phosphate in osteoblasts and their role in mineralizing the ECM. These observations may have important implications in deciphering both how normal bone forms and in understanding pathological mineralization. PMID:22879397
Densitometric and biochemical values of broiler tibias at different ages.
Barreiro, F R; Sagula, A L; Junqueira, O M; Pereira, G T; Baraldi-Artoni, S M
2009-12-01
The objective of this experiment was to determine the normal values of bone radiographic density (BRD) by using the optical densitometry in radiographic images and the biochemical values represented by serum calcium, ash percentage, and minerals (calcium, phosphorus, and magnesium) from tibia ash of Cobb broilers at 8, 22, and 43 d of age. A total of 14 broilers were used for densitometric analysis, and 15 were used for biochemical dosages. The BRD values increased (P < 0.05) with age and in all tibia regions (proximal epiphysis, diaphysis, and distal epiphysis), concluding that growth was a determinative factor for bone performance, demanding a higher BRD during broiler development. Tibia proximal epiphysis presented higher BRD values in relation to the other bone regions (P < 0.05), as a result of a possible biomechanical adaptation to ligaments and tension of the muscle tendons at this region, allowing the support of the muscle mass increase. The serum calcium values were kept constant, as a result of the appropriate nutritional levels of the diet that supported the animal homeostasis. The bone ash and mineral percentage increased (P < 0.05) at 22 d of age, due to the higher mineral requirement in this age. The correlation between bone densitometry and the invasive techniques showed that the bone densitometry can substitute the determination of mineral percentage in the ash. This experiment presented normal values of the noninvasive and invasive methods more used in aviculture, allowing us to compare, subsequently, pathological and physiological values or results of broilers fed with different diets.
Jarjou, Landing MA; Laskey, M Ann; Sawo, Yankuba; Goldberg, Gail R; Cole, Timothy J
2010-01-01
Background: Mobilization of maternal bone mineral partly supplies calcium for fetal and neonatal bone growth and development. Objective: We investigated whether pregnant women with low calcium intakes may have a more extensive skeletal response postpartum that may compromise their short- or long-term bone health. Design: In a subset of participants (n = 125) in a double-blind, randomized, placebo-controlled trial (International Trial Registry: ISRCTN96502494) in pregnant women in The Gambia, West Africa, with low calcium intakes (≈350 mg Ca/d), we measured bone mineral status of the whole body, lumbar spine, and hip by using dual-energy X-ray absorptiometry and measured bone mineral status of the forearm by using single-photon absorptiometry at 2, 13, and 52 wk lactation. We collected blood and urine from the subjects at 20 wk gestation and at 13 wk postpartum. Participants received calcium carbonate (1500 mg Ca/d) or a matching placebo from 20 wk gestation to parturition; participants did not consume supplements during lactation. Results: Women who received the calcium supplement in pregnancy had significantly lower bone mineral content (BMC), bone area (BA), and bone mineral density (BMD) at the hip throughout 12 mo lactation (mean ± SE difference: BMC = −10.7 ± 3.7%, P = 0.005; BA = −3.8 ± 1.9%, P = 0.05; BMD = −6.9 ± 2.6%, P = 0.01). The women also experienced greater decreases in bone mineral during lactation at the lumbar spine and distal radius and had biochemical changes consistent with greater bone mineral mobilization. Conclusions: Calcium supplementation in pregnant women with low calcium intakes may disrupt metabolic adaptation and may not benefit maternal bone health. Further study is required to determine if such effects persist long term or elicit compensatory changes in bone structure. PMID:20554790
Initial stages of calcium uptake and mineral deposition in sea urchin embryos
Vidavsky, Netta; Addadi, Sefi; Mahamid, Julia; Shimoni, Eyal; Ben-Ezra, David; Shpigel, Muki; Weiner, Steve; Addadi, Lia
2014-01-01
Sea urchin larvae have an endoskeleton consisting of two calcitic spicules. We reconstructed various stages of the formation pathway of calcium carbonate from calcium ions in sea water to mineral deposition and integration into the forming spicules. Monitoring calcium uptake with the fluorescent dye calcein shows that calcium ions first penetrate the embryo and later are deposited intracellularly. Surprisingly, calcium carbonate deposits are distributed widely all over the embryo, including in the primary mesenchyme cells and in the surface epithelial cells. Using cryo-SEM, we show that the intracellular calcium carbonate deposits are contained in vesicles of diameter 0.5–1.5 μm. Using the newly developed airSEM, which allows direct correlation between fluorescence and energy dispersive spectroscopy, we confirmed the presence of solid calcium carbonate in the vesicles. This mineral phase appears as aggregates of 20–30-nm nanospheres, consistent with amorphous calcium carbonate. The aggregates finally are introduced into the spicule compartment, where they integrate into the growing spicule. PMID:24344263
Initial stages of calcium uptake and mineral deposition in sea urchin embryos.
Vidavsky, Netta; Addadi, Sefi; Mahamid, Julia; Shimoni, Eyal; Ben-Ezra, David; Shpigel, Muki; Weiner, Steve; Addadi, Lia
2014-01-07
Sea urchin larvae have an endoskeleton consisting of two calcitic spicules. We reconstructed various stages of the formation pathway of calcium carbonate from calcium ions in sea water to mineral deposition and integration into the forming spicules. Monitoring calcium uptake with the fluorescent dye calcein shows that calcium ions first penetrate the embryo and later are deposited intracellularly. Surprisingly, calcium carbonate deposits are distributed widely all over the embryo, including in the primary mesenchyme cells and in the surface epithelial cells. Using cryo-SEM, we show that the intracellular calcium carbonate deposits are contained in vesicles of diameter 0.5-1.5 μm. Using the newly developed airSEM, which allows direct correlation between fluorescence and energy dispersive spectroscopy, we confirmed the presence of solid calcium carbonate in the vesicles. This mineral phase appears as aggregates of 20-30-nm nanospheres, consistent with amorphous calcium carbonate. The aggregates finally are introduced into the spicule compartment, where they integrate into the growing spicule.
Regulation of Cellular Calcium in Vestibular Supporting Cells by Otopetrin 1
Kim, Euysoo; Hyrc, Krzysztof L.; Speck, Judith; Lundberg, Yunxia W.; Salles, Felipe T.; Kachar, Bechara; Goldberg, Mark P.; Warchol, Mark E.
2010-01-01
Otopetrin 1 (OTOP1) is a multitransmembrane domain protein, which is essential for mineralization of otoconia, the calcium carbonate biominerals required for vestibular function, and the normal sensation of gravity. The mechanism driving mineralization of otoconia is poorly understood, but it has been proposed that supporting cells and a mechanism to maintain high concentrations of calcium are critical. Using Otop1 knockout mice and a utricular epithelial organ culture system, we show that OTOP1 is expressed at the apex of supporting cells and functions to increase cytosolic calcium in response to purinergic agonists, such as adenosine 5′-triphosphate (ATP). This is achieved by blocking mobilization of calcium from intracellular stores in an extracellular calcium-dependent manner and by mediating influx of extracellular calcium. These data support a model in which OTOP1 acts as a sensor of the extracellular calcium concentration near supporting cells and responds to ATP in the endolymph to increase intracellular calcium levels during otoconia mineralization. PMID:20554841
Calcium glycerophosphate and caries: a review of the literature.
Lynch, R J M
2004-01-01
To review studies in the dental literature regarding the anti-caries mode of action of glycerophosphate with special reference to calcium glycerophosphate. The cariostatic properties of calcium glycerophosphate have been demonstrated during numerous in vivo and in vitro studies. Several mechanisms have been suggested and these include plaque-pH buffering, elevation of plaque calcium and phosphate levels and direct interaction with dental mineral. There is credible evidence that calcium glycerophosphate has the potential to reduce the progression of caries via all of these mechanisms if it is applied frequently and at a sufficiently high concentration. Reduction of plaque mass has also been proposed as a cariostatic mechanism but this seems less likely. Animal studies have shown that the calcium glycerophosphate/sodium monofluorophosphate system can have a greater anti-caries effect than sodium monofluorophosphate alone and this was subsequently confirmed in a caries clinical trial. We conclude that elevation of calcium levels in plaque is the most likely explanation and that any means of enhancing this effect has significant promise as a means to further increase in anti-caries potential of the calcium glycerophosphate/sodium monofluorophosphate system compared to sodium monofluorophosphate alone.
Water quality characterization in some birimian aquifers of the Birim Basin, Ghana
Bruce, B.-Y.; Yidana, S.M.; Anku, Y.; Akabzaa, T.; Asiedu, D.
2009-01-01
The objective of this study was to determine the main controls on the hydrochemistry of groundwater in the study area. Mass balance modeling was used simultaneously with multivariate R-mode hierarchical cluster analysis to determine the significant sources of variation in the hydrochemistry. Two water types have been revealed in this area: (1) waters influenced more significantly by the weathering of silicate minerals from the underlying geology, and are rich in silica, sodium, calcium, bicarbonate, and magnesium ions, and (2) waters that have been influenced by the effects of fertilizers and other anthropogenic activities in the area. Mineral speciation and silicate mineral stability diagrams generated from the data suggest that montmorillonite, probably derived from the incongruent dissolution of feldspars and micas, is the most stable silicate phase in the groundwater. The apparent incongruent weathering of silicate minerals in the groundwater system has led to the enrichment of sodium, calcium, magnesium and bicarbonate ions as well as silica, leading to the supersaturation of calcite, aragonite, dolomite and quartz. Stability in the montmorillonite field suggests restricted flow conditions whereby groundwater residence time is relatively high, leading to greater contact of groundwater with the rock to enhance weathering. Cation exchange processes have also been determined to play minor roles in the hydrochemistry.
Presentation and management of osteoporosis presenting in association with pregnancy or lactation.
Kovacs, C S; Ralston, S H
2015-09-01
In this review, we summarize our current understanding of the pathophysiology of fragility fractures that occur for the first time during pregnancy and lactation, and provide guidance on appropriate investigations and treatment strategies. Most affected women will have had no prior bone density reading, and so the extent of bone loss that may have occurred during pregnancy or lactation is uncertain. During pregnancy, intestinal calcium absorption doubles in order to meet the fetal demand for calcium, but if maternal intake of calcium is insufficient to meet the combined needs of the mother and baby, the maternal skeleton will undergo resorption during the third trimester. During lactation, several hormonal changes, independent of maternal calcium intake, program a 5-10 % loss of trabecular mineral content in order to provide calcium to milk. After weaning the baby, the maternal skeleton is normally restored to its prior mineral content and strength. This physiological bone resorption during reproduction does not normally cause fractures; instead, women who do fracture are more likely to have additional secondary causes of bone loss and fragility. Transient osteoporosis of the hip may affect one or both femoral heads during pregnancy but it involves localized edema and not skeletal resorption. Case reports have described the use of calcitonin, bisphosphonates, strontium ranelate, teriparatide, vertebroplasty, and kyphoplasty to treat post-partum vertebral fractures. However, the need for such treatments is uncertain given that a progressive increase in bone mass subsequently occurs in most women who present with a fracture during pregnancy or lactation.
Chen, Luoping; Zheng, Lisha; Jiang, Jingyi; Gui, Jinpeng; Zhang, Lingyu; Huang, Yan; Chen, Xiaofang; Ji, Jing; Fan, Yubo
2016-09-01
Calcium hydroxide has been extensively used as the gold standard for direct pulp capping in clinical dentistry. It induces proliferation, migration, and mineralization in dental pulp stem cells (DPSCs), but the underlying mechanisms are still unclear. The aim of this study was to investigate the role of the mitogen-activated protein (MAP) kinase pathway in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Human DPSCs between passages 3 and 6 were used. DPSCs were preincubated with inhibitors of MAP kinases and cultured with calcium hydroxide. The phosphorylated MAP kinases were detected by Western blot analysis. Cell viability was analyzed via the methylthiazol tetrazolium assay. Cell migration was estimated using the wound healing assay. Alkaline phosphatase (ALP) expression was analyzed using the ALP staining assay. Mineralization was studied by alizarin red staining analysis. Calcium hydroxide significantly promoted the phosphorylation of the c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase. The inhibition of JNK and p38 signaling abolished calcium hydroxide-induced proliferation of DPSCs. The inhibition of JNK, p38, and extracellular signal-regulated kinase signaling suppressed the migration, ALP expression, and mineralization of DPSCs. Our study showed that the MAP kinase pathway was involved in calcium hydroxide-induced proliferation, migration, osteogenic differentiation, and mineralization in human DPSCs. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Invited review: Dairy intake and bone health: a viewpoint from the state of the art.
Caroli, A; Poli, A; Ricotta, D; Banfi, G; Cocchi, D
2011-11-01
The aim of this review was to focus on the complex relationships between milk and dairy products intake and bone health, with particular emphasis on osteoporosis. The literature was extensively examined to provide an objective overview of the most significant achievements on the subject. Osteoporosis can be defined as a disease characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture risk. Although the major determinants of peak bone mass and strength are genetic, major factors during childhood and adolescence may affect the ability to achieve peak bone mass. These include nutrition, particularly calcium and protein intake, physical activity, endocrine status, as well as exposure to a wide variety of risk factors. The role of calcium intake in determining bone mineral mass is well recognized to be the most critical nutritional factor to achieve optimal peak bone mass. The greatest amount of dietary calcium is obtained from milk and dairy foods, which also provide the human diet with vitamin D (particularly for products fortified with vitamin D), potassium, and other macro- and micronutrients. Although studies supporting the beneficial effects of milk or calcium on bone health are predominant in the literature, perplexity or discordance on this subject was expressed by some authors. Discordant data, mainly on the risk of fractures, provided limited proof of the unfavorable effect of dairy intake. More often, discordant works indicate no effect of dairy consumption on bone safety. Some considerations can be drawn from this viewpoint. Milk and dairy products are an optimal source of calcium as well as of other limiting nutrients (e.g., potassium and magnesium), with important effects on bone health. Bioactive components occurring in milk and dairy products may play an essential role on bone metabolism, as shown by in vivo and in vitro studies on colostrum acidic proteins and milk basic proteins. Calcium intake positively affects bone mass and is crucial in childhood and youth for correct bone development. In elderly people, calcium intake as well as vitamin D availability should be carefully checked. As a general conclusion, calcium is essential for bone health, although it will not prevent bone loss due to other factors; in this context, milk and dairy foods are bioavailable, relatively inexpensive sources of calcium for the human diet. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Bone mass of female dance students prior to professional dance training: A cross-sectional study
Amorim, Tânia; Metsios, George S.; Wyon, Matthew; Nevill, Alan M.; Flouris, Andreas D.; Maia, José; Teixeira, Eduardo; Machado, José Carlos; Marques, Franklim; Koutedakis, Yiannis
2017-01-01
Background Professional dancers are at risk of developing low bone mineral density (BMD). However, whether low BMD phenotypes already exist in pre-vocational dance students is relatively unknown. Aim To cross-sectionally assess bone mass parameters in female dance students selected for professional dance training (first year vocational dance students) in relation to aged- and sex-matched controls. Methods 34 female selected for professional dance training (10.9yrs ±0.7) and 30 controls (11.1yrs ±0.5) were examined. Anthropometry, pubertal development (Tanner) and dietary data (3-day food diary) were recorded. BMD and bone mineral content (BMC) at forearm, femur neck (FN) and lumbar spine (LS) were assessed using Dual-Energy X-Ray Absorptiometry. Volumetric densities were estimated by calculating bone mineral apparent density (BMAD). Results Dancers were mainly at Tanner pubertal stage I (vs. stage IV in controls, p<0.001), and demonstrated significantly lower body weight (p<0.001) and height (p<0.01) than controls. Calorie intake was not different between groups, but calcium intake was significantly greater in dancers (p<0.05). Dancers revealed a significantly lower BMC and BMD values at all anatomical sites (p<0.001), and significantly lower BMAD values at the LS and FN (p<0.001). When adjusted for covariates (body weight, height, pubertal development and calcium intake), dance students continued to display a significantly lower BMD and BMAD at the FN (p<0.05; p<0.001) at the forearm (p<0.01). Conclusion Before undergoing professional dance training, first year vocational dance students demonstrated inferior bone mass compared to controls. Longitudinal models are required to assess how bone health-status changes with time throughout professional training. PMID:28678833
Bone mass of female dance students prior to professional dance training: A cross-sectional study.
Amorim, Tânia; Metsios, George S; Wyon, Matthew; Nevill, Alan M; Flouris, Andreas D; Maia, José; Teixeira, Eduardo; Machado, José Carlos; Marques, Franklim; Koutedakis, Yiannis
2017-01-01
Professional dancers are at risk of developing low bone mineral density (BMD). However, whether low BMD phenotypes already exist in pre-vocational dance students is relatively unknown. To cross-sectionally assess bone mass parameters in female dance students selected for professional dance training (first year vocational dance students) in relation to aged- and sex-matched controls. 34 female selected for professional dance training (10.9yrs ±0.7) and 30 controls (11.1yrs ±0.5) were examined. Anthropometry, pubertal development (Tanner) and dietary data (3-day food diary) were recorded. BMD and bone mineral content (BMC) at forearm, femur neck (FN) and lumbar spine (LS) were assessed using Dual-Energy X-Ray Absorptiometry. Volumetric densities were estimated by calculating bone mineral apparent density (BMAD). Dancers were mainly at Tanner pubertal stage I (vs. stage IV in controls, p<0.001), and demonstrated significantly lower body weight (p<0.001) and height (p<0.01) than controls. Calorie intake was not different between groups, but calcium intake was significantly greater in dancers (p<0.05). Dancers revealed a significantly lower BMC and BMD values at all anatomical sites (p<0.001), and significantly lower BMAD values at the LS and FN (p<0.001). When adjusted for covariates (body weight, height, pubertal development and calcium intake), dance students continued to display a significantly lower BMD and BMAD at the FN (p<0.05; p<0.001) at the forearm (p<0.01). Before undergoing professional dance training, first year vocational dance students demonstrated inferior bone mass compared to controls. Longitudinal models are required to assess how bone health-status changes with time throughout professional training.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false If I am mining calcium chloride, may I... Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the commingled sodium chloride? Yes. If you are producing calcium chloride in...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false If I am mining calcium chloride, may I... Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the commingled sodium chloride? Yes. If you are producing calcium chloride in...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false If I am mining calcium chloride, may I... Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the commingled sodium chloride? Yes. If you are producing calcium chloride in...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false If I am mining calcium chloride, may I... Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the commingled sodium chloride? Yes. If you are producing calcium chloride in...
Enamel-like apatite crown covering amorphous mineral in a crayfish mandible
Bentov, Shmuel; Zaslansky, Paul; Al-Sawalmih, Ali; Masic, Admir; Fratzl, Peter; Sagi, Amir; Berman, Amir; Aichmayer, Barbara
2012-01-01
Carbonated hydroxyapatite is the mineral found in vertebrate bones and teeth, whereas invertebrates utilize calcium carbonate in their mineralized organs. In particular, stable amorphous calcium carbonate is found in many crustaceans. Here we report on an unusual, crystalline enamel-like apatite layer found in the mandibles of the arthropod Cherax quadricarinatus (freshwater crayfish). Despite their very different thermodynamic stabilities, amorphous calcium carbonate, amorphous calcium phosphate, calcite and fluorapatite coexist in well-defined functional layers in close proximity within the mandible. The softer amorphous minerals are found primarily in the bulk of the mandible whereas apatite, the harder and less soluble mineral, forms a wear-resistant, enamel-like coating of the molar tooth. Our findings suggest a unique case of convergent evolution, where similar functional challenges of mastication led to independent developments of structurally and mechanically similar, apatite-based layers in the teeth of genetically remote phyla: vertebrates and crustaceans. PMID:22588301
Inulin and oligofructose and mineral metabolism: the evidence from animal trials.
Scholz-Ahrens, Katharina E; Schrezenmeir, Jürgen
2007-11-01
Nondigestible oligosaccharides have been shown to increase the absorption of several minerals (calcium, magnesium, in some cases phosphorus) and trace elements (mainly copper, iron, zinc). Inulin-type fructans including oligofructose and fructooligosaccharides derived from sucrose by enzymatic transfructosylation are the best investigated food ingredients in this respect. The stimulation of absorption was more pronounced when the demand for calcium was high, i.e., in animals in the rapid growing stage and in animals with impaired calcium absorption because of either ovariectomy or gastrectomy. Even a small stimulation of calcium absorption increased the mineral accumulation in the skeleton because of its persisting effect over months. Inulin-type fructans stimulated mineral absorption and bone mineral accretion when combined with probiotic lactobacilli and in the presence of antibiotics. Direct comparison of different inulin-type fructans revealed a more pronounced effect by inulin or a mixture of long-chain inulin and oligofructose than by oligofructose alone. Mechanisms on how inulin-type fructans mediate this effect include acidification of the intestinal lumen by short-chain fatty acids increasing solubility of minerals in the gut, enlargement of the absorption surface, increased expression of calcium-binding proteins mainly in the large intestine, modulated expression of bone-relevant cytokines, suppression of bone resorption, increased bioavailability of phytoestrogens, and, via stimulation of beneficial commensal microorganisms, increase of calcium uptake by enterocytes. Under certain conditions, inulin-type fructans may improve mineral absorption by their impact on the amelioration of gut health including stabilization of the intestinal flora and reduction of inflammation. The abundance of reports indicate that inulin-type fructans are promising substances that could help to improve the supply with available calcium in human nutrition and by this contribute to bone health.
Phosphate toxicity and vascular mineralization.
Razzaque, Mohammed S
2013-01-01
Vascular calcification or mineralization is a major complication seen in patients with advanced stages of chronic kidney disease (CKD), and it is associated with markedly increased morbidity and mortality. Most of the CKD-related vascular mineralization is attributable to abnormal mineral ion metabolism. Elevated serum calcium and phosphate levels, along with increased calcium-phosphorus byproduct, and the use of active vitamin D metabolites are thought to be the predisposing factors for developing vascular mineralization in patients with CKD. Recent experimental studies have shown that vascular mineralization can be suppressed by reducing serum phosphate levels, even in the presence of extremely high serum calcium and 1,25-dihydroxyvitamin D levels, indicating that reducing 'phosphate toxicity' should be the important therapeutic priority in CKD patients for minimizing the risk of developing vascular mineralization and the disease progression. Copyright © 2013 S. Karger AG, Basel.
Borer, Katarina T
2005-01-01
Osteoporosis is a serious health problem that diminishes quality of life and levies a financial burden on those who fear and experience bone fractures. Physical activity as a way to prevent osteoporosis is based on evidence that it can regulate bone maintenance and stimulate bone formation including the accumulation of mineral, in addition to strengthening muscles, improving balance, and thus reducing the overall risk of falls and fractures. Currently, our understanding of how to use exercise effectively in the prevention of osteoporosis is incomplete. It is uncertain whether exercise will help accumulate more overall peak bone mass during childhood, adolescence and young adulthood. Also, the consistent effectiveness of exercise to increase bone mass, or at least arrest the loss of bone mass after menopause, is also in question. Within this framework, section 1 introduces mechanical characteristics of bones to assist the reader in understanding their responses to physical activity. Section 2 reviews hormonal, nutritional and mechanical factors necessary for the growth of bones in length, width and mineral content that produce peak bone mass in the course of childhood and adolescence using a large sample of healthy Caucasian girls and female adolescents for reference. Effectiveness of exercise is evaluated throughout using absolute changes in bone with the underlying assumption that useful exercise should produce changes that approximate or exceed the absolute magnitude of bone parameters in a healthy reference population. Physical activity increases growth in width and mineral content of bones in girls and adolescent females, particularly when it is initiated before puberty, carried out in volumes and at intensities seen in athletes, and accompanied by adequate caloric and calcium intakes. Similar increases are seen in young women following the termination of statural growth in response to athletic training, but not to more limited levels of physical activity characteristic of longitudinal training studies. After 9-12 months of regular exercise, young adult women often show very small benefits to bone health, possibly because of large subject attrition rates, inadequate exercise intensity, duration or frequency, or because at this stage of life accumulation of bone mass may be at its natural peak. The important influence of hormones as well as dietary and specific nutrient abundance on bone growth and health are emphasised, and premature bone loss associated with dietary restriction and estradiol withdrawal in exercise-induced amenorrhoea is described. In section 3, the same assessment is applied to the effects of physical activity in postmenopausal women. Studies of postmenopausal women are presented from the perspective of limitations of the capacity of the skeleton to adapt to mechanical stress of exercise due to altered hormonal status and inadequate intake of specific nutrients. After menopause, effectiveness of exercise to increase bone mineral depends heavily on adequate availability of dietary calcium. Relatively infrequent evidence that physical activity prevents bone loss or increases bone mineral after menopause may be a consequence of inadequate calcium availability or low intensity of exercise in training studies. Several studies with postmenopausal women show modest increases in bone mineral toward the norm seen in a healthy population in response to high-intensity training. Physical activities continue to stimulate increases in bone diameter throughout the lifespan. These exercise-stimulated increases in bone diameter diminish the risk of fractures by mechanically counteracting the thinning of bones and increases in bone porosity. Seven principles of bone adaptation to mechanical stress are reviewed in section 4 to suggest how exercise by human subjects could be made more effective. They posit that exercise should: (i) be dynamic, not static; (ii) exceed a threshold intensity; (iii) exceed a threshold strain frequency; (iv) be relatively brief but intermittent; (v) impose an unusual loading pattern on the bones; (vi) be supported by unlimited nutrient energy; and (vii) include adequate calcium and cholecalciferol (vitamin D3) availability.
Calcium Intake, Major Dietary Sources and Bone Health Indicators in Iranian Primary School Children
Omidvar, Nasrin; Neyestani, Tirang-Reza; Hajifaraji, Majid; Eshraghian, Mohammad-Reza; Rezazadeh, Arezoo; Armin, Saloumeh; Haidari, Homa; Zowghi, Telma
2015-01-01
Background: Adequate calcium intake may have a crucial role with regards to prevention of many chronic diseases, including hypertension, hypercholesterolemia, different types of cancer, obesity and osteoporosis. In children, sufficient calcium intake is especially important to support the accelerated growth spurt during the preteen and teenage years and to increase bone mineral mass to lay the foundation for older age. Objectives: This study aimed to assess daily calcium intake in school-age children to ensure whether they fulfill the FGP dairy serving recommendations, the recommended levels of daily calcium intake and to assess the relationship between dietary calcium intake and major bone health indicators. Patients and Methods: A total of 501 Iranian school-age children were randomly selected. Calcium intake was assessed using a semi-quantitative food frequency questionnaire. Bone health indicators were also assessed. Results: Dairy products contributed to 69.3% of the total calcium intake of the children. Daily adequate intake of calcium was achieved by 17.8% of children. Only 29.8% met the Food guide pyramid recommendations for dairy intake. Dietary calcium intake was not significantly correlated with serum calcium and other selected biochemical indicators of bone health. Conclusions: The need for planning appropriate nutrition strategies for overcoming inadequate calcium intake in school age children in the city of Tehran is inevitable. PMID:26199684
Manganese-enhanced magnetic resonance microscopy of mineralization
Chesnick, I.E.; Todorov, T.I.; Centeno, J.A.; Newbury, D.E.; Small, J.A.; Potter, K.
2007-01-01
Paramagnetic manganese (II) can be employed as a calcium surrogate to sensitize magnetic resonance microscopy (MRM) to the processing of calcium during bone formation. At high doses, osteoblasts can take up sufficient quantities of manganese, resulting in marked changes in water proton T1, T2 and magnetization transfer ratio values compared to those for untreated cells. Accordingly, inductively coupled plasma mass spectrometry (ICP-MS) results confirm that the manganese content of treated cell pellets was 10-fold higher than that for untreated cell pellets. To establish that manganese is processed like calcium and deposited as bone, calvaria from the skull of embryonic chicks were grown in culture medium supplemented with 1 mM MnCl2 and 3 mM CaCl2. A banding pattern of high and low T2 values, consistent with mineral deposits with high and low levels of manganese, was observed radiating from the calvarial ridge. The results of ICP-MS studies confirm that manganese-treated calvaria take up increasing amounts of manganese with time in culture. Finally, elemental mapping studies with electron probe microanalysis confirmed local variations in the manganese content of bone newly deposited on the calvarial surface. This is the first reported use of manganese-enhanced MRM to study the process whereby calcium is taken up by osteoblasts cells and deposited as bone. ?? 2007 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Sala, M.; Delmonte, B.; Frezzotti, M.; Proposito, M.; Scarchilli, C.; Maggi, V.; Artioli, G.; Dapiaggi, M.; Marino, F.; Ricci, P. C.; De Giudici, G.
2008-07-01
Micrometre-sized aeolian dust particles stored in Antarctic firn and ice layers are a useful tool for reconstructing climate and environmental changes in the past. The mineral content, particle concentration and chemical composition of modern dust in firn cores from the peripherycal dome (Talos Dome) and coastal area of East Antarctica (Ross Sea sector) were investigated. During analyses there was a considerable decrease in microparticle concentrations within a few hours of ice sample melting, accompanied by a systematic increase in the concentration of calcium ions (Ca 2+) in solution. Based on mineralogical phase analyses, which reveal the presence of anhydrous and hydrous calcium carbonates such as calcite (CaCO 3), monohydrocalcite (CaCO 3·H 2O) and ikaite (CaCO 3·6H 2O, hexahydrate calcium carbonate), the observed variations in concentrations are ascribed to the partial dissolution of the carbonate content of samples. Soluble carbonate compounds are thus primary aerosols included into the samples along with insoluble aluminosilicate minerals. We hypothesize hydrous carbonates may derive from the sea ice surface, where ikaite typically forms at the early stages of sea ice formation. Back trajectory calculations show that favourable events for air mass advection from the sea ice surface to Talos Dome are rare but likely to occur.
Effect of two forms of alendronate administration upon bone mass after two years of treatment.
Sosa, M; Hernández, D; Segarra, M C; Gómez, A; de la Peña, E; Betancor, P
2002-01-01
The efficacy of alendronate in slowing the loss of bone mass, or even in increasing it, in osteoporotic patients and thus reducing the risk of new fractures has been described. Nevertheless, the way of taking this drug, together with its side effects, sometimes produces withdrawals. In this study, we analyzed if an alternative way of taking the alendronate improves the follow-up of the treatment and if it had the same effect on bone mineral metabolism than the traditional way of prescription. An open, intention-to-treat study, with follow-up of 2 yr was conducted. Eighty women suffering from postmenopausal osteoporosis were included in the study. They were classified in a random manner into two groups, each one of them received 10 mg/d alendronate, together with 1.2 g of calcium and 800 IU of Vitamin D3. Group I received the drug fasting, before breakfast, as usually prescribed and group II received the alendronate fasting, at noon, before lunch. Biochemical markers of bone remodeling were determined. Total alkaline phosphatase, osteocalcin, tartrate-resistant acid phosphatase, urine calcium/creatinine ratio, crosslinked N-telopeptides of type I collagen/creatinine ratio, serum calcium, and parathyroid hormone were also determined, and a lateral dorsolumbar radiography of the spine was performed. Bone mineral density was determined in the lumbar spine by dual-energy X-ray absorptiometry and quantitative computed tomography and by dual-energy X-ray absorptiometry in the proximal femur. Both groups showed an increase in bone mineral density in the lumbar spine and in the proximal femur, which was statistically significant after 1 yr of treatment in the range between 1.5% and 4.3%, depending on the anatomical localization where bone mineral density was measured. There was also an important decrease in the biochemical markers of bone remodeling, between 5.6% and 42.5%, depending on the biochemical marker; the decrease of amino-terminal telopetide during the first year was more important. The group that received alendronate in the morning reported a significantly higher number of withdrawals than the group that received the drug at noon. The alternative administration of 10 mg alendronate at noon had the same effect on bone mineral metabolism than its traditional administration in the morning, but the rate of withdrawals was significantly lower.
NASA Astrophysics Data System (ADS)
Sullivan, R. C.; Moore, M. J.; Petters, M. D.; Laskin, A.; Roberts, G. C.; Kreidenweis, S. M.; Prather, K. A.
2009-05-01
Our laboratory investigations of mineral dust particle hygroscopicity are motivated by field observations of the atmospheric processing of dust. During ACE-Asia we observed sulphate and nitrate to be strongly segregated from each other in individual aged Asian dust particles. CCN activation curves of pure calcium minerals as proxies for fresh (calcium carbonate) and aged (calcium sulphate, nitrate, chloride) dust indicate that this mixing state would cause a large fraction of aged dust particles to remain poor warm cloud nucleation potential, contrary to previous assumptions. The enrichment of oxalic acid in calcium-rich dust particles could have similar effects due to the formation of insoluble calcium oxalate. Soluble calcium nitrate and chloride reaction products are hygroscopic and will transform mineral dust into excellent CCN. Generating insoluble mineral particles wet by atomization produced particles with much higher hygroscopicity then when resuspended dry. The atomized particles are likely composed of dissolved residuals and do not properly reflect the chemistry of dry mineral powders. Aerosol flow tube experiments were employed to study the conversion of calcium carbonate into calcium nitrate via heterogeneous reaction with nitric acid, with simultaneous measurements of the reacted particles' chemistry and hygroscopicity. The timescale for this hygroscopic conversion was found to occur on the order of a few hours under tropospheric conditions. This implies that the conversion of non-hygroscopic calcite- containing dust into hygroscopic particles will be controlled by the availability of nitric acid, and not by the atmospheric residence time. Results from recent investigations of the effect of secondary coatings on the ice nucleation properties of dust particles will also be presented. The cloud formation potential of aged dust particles depends on both the quantity and form of the secondary species that have reacted or mixed with the dust. These results have important implications for the treatment of mineral dust particles in global chemistry and climate models.
Disorders of calcium, phosphorus, and magnesium metabolism in the neonate
USDA-ARS?s Scientific Manuscript database
Approximately 98% of the calcium, 80% of the phosphorus, and 65% of the magnesium in the body are in the skeleton. These elements, often referred to as the "bone minerals" are also constituents of the intracellular and extracellular spaces. The metabolism of these bone minerals and mineralization of...
An update on childhood bone health: mineral accrual, assessment and treatment.
Sopher, Aviva B; Fennoy, Ilene; Oberfield, Sharon E
2015-02-01
To update the reader's knowledge about the factors that influence bone mineral accrual and to review the advances in the assessment of bone health and treatment of bone disorders. Maternal vitamin D status influences neonatal calcium levels, bone mineral density (BMD) and bone size. In turn, BMD z-score tends to track in childhood. These factors highlight the importance of bone health as early as fetal life. Dual-energy x-ray absorptiometry is the mainstay of clinical bone health assessment in this population because of the availability of appropriate reference data. Recently, more information has become available about the assessment and treatment of bone disease in chronically ill pediatric patients. Bone health must become a health focus starting prenatally in order to maximize peak bone mass and to prevent osteoporosis-related bone disease in adulthood. Vitamin D, calcium and weight-bearing activity are the factors of key importance throughout childhood in achieving optimal bone health as BMD z-score tracks through childhood and into adulthood. Recent updates of the International Society for Clinical Densitometry focus on the appropriate use of dual-energy x-ray absorptiometry in children of all ages, including children with chronic disease, and on the treatment of pediatric bone disease.
Control of the spread of inorganic elements by shelterbelt in agricultural landscape
NASA Astrophysics Data System (ADS)
Życzyńska-Bałoniak, Irena; Wojciech Szajdak, Lech
2010-05-01
Non-point pollution from agricultural lands involves primarily three transport processes: runoff, leaching, and erosion-sedimentation. The primary transport medium for all three processes is water, which is also a significant carrier of nutrients and sediments. Hydrologic processes important relative to non-point pollution are: (a) infiltration, (b) subsurface flow, (c) overland flow. A better understanding of the impact of shelterbelt on the decrease the quantities of chemical compounds in ground water should increase our ability to predict the improvement of the quality of ground water. The objective of this study was to evaluate the effect of shelterbelt on the decrease of calcium, magnesium and inorganic carbon in ground water passing through the shelterbelt from adjoining cultivated fields. The investigations were carried out in Turew in Chlapowski's Agroecological Park situated 40 km South-West of Poznań (West Polish Lowland). Afforestations represent well developed network of shelterbelts (mid-field rows of trees afforestation). The established network of shelterbelts in Turew is the unique in Europe. Ground water under cultivated field and shelterbelt from the artificial wells ones a month during 7 years from 2000 to 2006 was sampled and investigated. Ground water under shelterbelt flows away from adjoining cultivated field and passing through the shelterbelt. The first distance of this shelterbelt 104 m long is located on mineral soils (division-autogenic soils, order-brown forest soils, type-hapludalfs, subtype-glossudalfs) next from 104 to 125 m on mineral organic soils (division-hydrogenic soils, order-post-bog, soils, type-mucky soils, subtype-muckous). Calcium, magnesium and mineral carbon quantities have been investigated in the ground water of shelterbelts. The direction of water flow was estimated on the basis of the water level in the wells. Shelterbelt includes different species with the dominations of the maple, ash, beech, and hawthorn. Ground water samples were taken from the wells located (a) in the border between adjoining cultivated fields and shelterbelts, and (b) in the distances 62 m, 104 m and 125 m from the edge of the shelterbelt. The concentrations of calciumand magnesium and also mineral carbon were studied by examining ground water filtered by the filter paper Whatman GT/C. The concentrations of calcium and magnesium were investigated by the method by Hermanowicz. Dry masses were isolated by the freeze-dried and drying to the constant of weight at 105oC. Total organic carbon, dissolved organic carbon and mineral carbon were measured on Total Organic Carbon Analyzer 5050A, ASI 5000A auto sampler, SSM - 5000A solid sample module, (Shimadzu, Japan). Total amount of yearly rainfall was in 2000 - 671 mm, 2001 - 544 mm, 2002 - 495 mm, 2003 - 449 mm, 2004 - 672 mm, 2005 - 551 mm, 2006 - 578 mm. Mean temperatures ranged from 9.2 to 13.3oC. The highest temperature +23.5oC was measured in July 2000, and the lowest -6.4oC observed in January 2006. The precision based on replicate analyses, were ± 4% for Ca+2, ± 3% for Mg+2, ± 4% for dry mass. All the determinations were run in triplicate, and the results were averaged. The differences among the concentrations of calcium, magnesium and mineral carbon were attributed solely of width of the shelterbelt. Shelterbelt revealed the improvement in the quality of ground water. Concerns over the environmental impacts of the elements of agricultural landscapes have focused attention on the study of calcium, magnesium, mineral carbon in ground water. These investigations have shown high contents of chemical compounds migrates ground water from cultivated fields. Ground water under cultivated field revealed high concentrations of calcium, which yearly mean contents are equaled from 81.9 to 179.2 mg/l. It was proved that biogeochemical barrier such as shelterbelt efficiency decrease the quantity of chemical compounds in ground water. The highest decrease of determined forms in the first distance of shelterbelt (62 m) and ranged for calcium from 26 to 34%, magnesium to 26% and mineral carbon to 71% was observed. On the basis of all aspects it seems that the first distance 62 m of shelterbelt is the most efficient for the function as biogeochemical barrier.
Ogata, Fumihiko; Nagai, Noriaki; Ito, Yoshimasa; Kawasaki, Naohito
2014-01-01
Since osteoporosis is a major public health problem in Japan, it is important to clarify the effect of high-mineral drinking water consumption on osteogenesis. Therefore, in this study, we investigated the relationship between high-mineral drinking water consumption and osteogenesis in ovariectomized rats that received a low-calcium diet and purified water (PW group) or a low-calcium diet and high-mineral drinking water (CR group). High-mineral drinking water affected the rats' body weight. After 3 months, the bone density of the CR group was higher than that of the PW group (p<0.05). Furthermore, the CR group showed a decrease in the amount of calcium in the bones after 3 months. These results suggest that high-mineral drinking water contributes to the maintenance of bone density and not to the amount of calcium in bone. On the other hand, serum alkaline phosphatase levels in the PW group at 3 months were higher than those in the CR group, which indicates that the blood concentration of calcium in the CR group was maintained. Moreover, the amount of magnesium in the bones and the blood concentration of magnesium in the CR group after 3 months were higher than the corresponding values in the PW group. These results suggest that consumption of high-mineral drinking water could be beneficial for osteogenesis (i.e., for maintaining bone quantity).
Changes in oxidative potential of soil and fly ash after reaction with gaseous nitric acid
NASA Astrophysics Data System (ADS)
Zhan, Ying; Ginder-Vogel, Matthew; Shafer, Martin M.; Rudich, Yinon; Pardo, Michal; Katra, Itzhak; Katoshevski, David; Schauer, James J.
2018-01-01
The goal of this study was to examine the impact of simulated atmospheric aging on the oxidative potential of inorganic aerosols comprised primarily of crustal materials. Four soil samples and one coal fly ash sample were artificially aged in the laboratory through exposure to the vapor from 15.8 M nitric acid solution for 24 h at room temperature. Native and acid-aged samples were analyzed with a cellular macrophage and acellular dithionthreitol assays to determine oxidative potential. Additionally, the samples were analyzed to determine the concentration of 50 elements, both total and the water-soluble fraction of these elements by Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICMS) and crystalline mineral composition using X-ray Diffraction (XRD). The results show that reactions with gaseous nitric acid increase the water-soluble fraction of many elements, including calcium, iron, magnesium, zinc, and lead. The mineral composition analysis documented that calcium-rich minerals present in the soils (e.g., calcite) are converted into different chemical forms, such as calcium nitrate (Ca(NO3)2). The nitric acid aging process, which can occur in the atmosphere, leads to a 200-600% increase in oxidative potential, as measured by cellular and acellular assays. This laboratory study demonstrates that the toxic effects of aged versus freshly emitted atmospheric dust may be quite different. In addition, the results suggest that mineralogical analysis of atmospheric dust may be useful in understanding its degree of aging.
Li, Chen; Solomons, Noel W; Scott, Marilyn E; Koski, Kristine G
2016-10-01
Breast milk is the recommended source of nutrients for infant growth, but its adequacy to meet infants' mineral and trace element needs is unknown. We used breast-milk mineral and trace element concentrations of Guatemalan mothers at 3 lactation stages to estimate total daily intakes and to determine whether intakes were associated with early infant growth. In this cross-sectional study, breast-milk samples were collected from Mam-Mayan mothers during transitional (5-17 d, n = 56), early (18-46 d, n = 75), and established (4-6 mo, n = 103) lactation; z scores for weight (WAZ), length (LAZ), and head circumference (HCAZ) were measured. Concentrations of 11 minerals (calcium, potassium, magnesium, sodium, copper, iron, manganese, rubidium, selenium, strontium, and zinc) were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). WHO equations were used to calculate the estimated energy requirement, which was divided by the energy density of breast milk to estimate daily milk volume, and this number was multiplied by breast-milk mineral concentrations to estimate intakes. Principal component analyses identified clusters of minerals; principal components (PCs) were used in regression analyses for anthropometric outcomes. Estimated breast-milk intakes during established lactation were insufficient to compensate for the lower milk sodium, copper, manganese, and zinc concentrations in male infants and the lower sodium, iron and manganese concentrations in female infants. Estimated intakes of calcium, magnesium, potassium, sodium, and selenium were below the Institute of Medicine Adequate Intake for both sexes at all 3 stages of lactation. In early lactation, multiple linear regressions showed that PC1 (calcium, magnesium, potassium, rubidium, and strontium intakes) was positively associated with WAZ, LAZ, and HCAZ. In established lactation, the same PC with sodium added was positively associated with all 3 anthropometric outcomes; a second PC (PC2: zinc, copper, and selenium intakes) was associated with WAZ and LAZ but not HCAZ. Breast milk may be inadequate in selected minerals and trace elements where higher estimated intakes were associated with greater infant growth. © 2016 American Society for Nutrition.
Calcium isotope constraints on the end-Permian mass extinction
Payne, Jonathan L.; Turchyn, Alexandra V.; Paytan, Adina; DePaolo, Donald J.; Lehrmann, Daniel J.; Yu, Meiyi; Wei, Jiayong
2010-01-01
The end-Permian mass extinction horizon is marked by an abrupt shift in style of carbonate sedimentation and a negative excursion in the carbon isotope (δ13C) composition of carbonate minerals. Several extinction scenarios consistent with these observations have been put forward. Secular variation in the calcium isotope (δ44/40Ca) composition of marine sediments provides a tool for distinguishing among these possibilities and thereby constraining the causes of mass extinction. Here we report δ44/40Ca across the Permian-Triassic boundary from marine limestone in south China. The δ44/40Ca exhibits a transient negative excursion of ∼0.3‰ over a few hundred thousand years or less, which we interpret to reflect a change in the global δ44/40Ca composition of seawater. CO2-driven ocean acidification best explains the coincidence of the δ44/40Ca excursion with negative excursions in the δ13C of carbonates and organic matter and the preferential extinction of heavily calcified marine animals. Calcium isotope constraints on carbon cycle calculations suggest that the average δ13C of CO2 released was heavier than -28‰ and more likely near -15‰; these values indicate a source containing substantial amounts of mantle- or carbonate-derived carbon. Collectively, the results point toward Siberian Trap volcanism as the trigger of mass extinction. PMID:20421502
Neues, Frank; Hild, Sabine; Epple, Matthias; Marti, Othmar; Ziegler, Andreas
2011-07-01
The main mineral components of the isopod cuticle consists of crystalline magnesium calcite and amorphous calcium carbonate. During moulting isopods moult first the posterior and then the anterior half of the body. In terrestrial species calcium carbonate is subject to resorption, storage and recycling in order to retain significant fractions of the mineral during the moulting cycle. We used synchrotron X-ray powder diffraction, elemental analysis and Raman spectroscopy to quantify the ACC/calcite ratio, the mineral phase distribution and the composition within the anterior and posterior tergite cuticle during eight different stages of the moulting cycle of Porcellio scaber. The results show that most of the amorphous calcium carbonate (ACC) is resorbed from the cuticle, whereas calcite remains in the old cuticle and is shed during moulting. During premoult resorption of ACC from the posterior cuticle is accompanied by an increase within the anterior tergites, and mineralization of the new posterior cuticle by resorption of mineral from the anterior cuticle. This suggests that one reason for using ACC in cuticle mineralization is to facilitate resorption and recycling of cuticular calcium carbonate. Furthermore we show that ACC precedes the formation of calcite in distal layers of the tergite cuticle. Copyright © 2011 Elsevier Inc. All rights reserved.
Stable prenucleation mineral clusters are liquid-like ionic polymers
Demichelis, Raffaella; Raiteri, Paolo; Gale, Julian D.; Quigley, David; Gebauer, Denis
2011-01-01
Calcium carbonate is an abundant substance that can be created in several mineral forms by the reaction of dissolved carbon dioxide in water with calcium ions. Through biomineralization, organisms can harness and control this process to form various functional materials that can act as anything from shells through to lenses. The early stages of calcium carbonate formation have recently attracted attention as stable prenucleation clusters have been observed, contrary to classical models. Here we show, using computer simulations combined with the analysis of experimental data, that these mineral clusters are made of an ionic polymer, composed of alternating calcium and carbonate ions, with a dynamic topology consisting of chains, branches and rings. The existence of a disordered, flexible and strongly hydrated precursor provides a basis for explaining the formation of other liquid-like amorphous states of calcium carbonate, in addition to the non-classical behaviour during growth of amorphous calcium carbonate. PMID:22186886
Template-assisted mineral formation via an amorphous liquid phase precursor route
NASA Astrophysics Data System (ADS)
Amos, Fairland F.
The search for alternative routes to synthesize inorganic materials has led to the biomimetic route of producing ceramics. In this method, materials are manufactured at ambient temperatures and in aqueous solutions with soluble additives and insoluble matrix, similar to the biological strategy for the formation of minerals by living organisms. Using this approach, an anionic polypeptide additive was used to induce an amorphous liquid-phase precursor to either calcium carbonate or calcium phosphate. This precursor was then templated on either organic or inorganic substrates. Non-equilibrium morphologies, such as two-dimensional calcium carbonate films, one-dimensional calcium carbonate mesostructures and "molten" calcium phosphate spherulites were produced, which are not typical of the traditional (additive-free) solution grown crystals in the laboratory. In the study of calcium carbonate, the amorphous calcium carbonate mineral formed via the liquid-phase precursor, either underwent a dissolution-recrystallization event or a pseudo-solid-state transformation to produce different morphologies and polymorphs of the mineral. Discrete or aggregate calcite crystals were formed via the dissolution of the amorphous phase to allow the reprecipitation of the stable crystal. Non-equilibrium morphologies, e.g., films, mesotubules and mesowires were templated using organic and inorganic substrates and compartments. These structures were generated via an amorphous solid to crystalline solid transformation. Single crystalline tablets and mesowires of aragonite, which are reported to be found only in nature as skeletal structures of marine organisms, such as mollusk nacre and echinoderm teeth, were successfully synthesized. These biomimetic structures were grown via the polymer-induced liquid-phase precursor route in the presence of magnesium. Only low magnesium-bearing calcite was formed in the absence of the polymer. A similar approach of using a polymeric additive was implemented in calcium phosphate. Spherulitic crystals and films, seemingly formed from a molten state, were produced. These structures served as nucleating surfaces for the radial formation of calcium oxalate minerals. The composite calcium phosphate-calcium oxalate assemblies are similar to the core-shell structures found in certain kidney stones.
Carbon dioxide released from subduction zones by fluid-mediated reactions
NASA Astrophysics Data System (ADS)
Ague, Jay J.; Nicolescu, Stefan
2014-05-01
The balance between the subduction of carbonate mineral-bearing rocks into Earth's mantle and the return of CO2 to the atmosphere by volcanic and metamorphic degassing is critical to the carbon cycle. Carbon is thought to be released from subducted rocks mostly by simple devolatilization reactions. However, these reactions will also retain large amounts of carbon within the subducting slab and have difficulty in accounting for the mass of CO2 emitted from volcanic arcs. Carbon release may therefore occur via fluid-induced dissolution of calcium carbonate. Here we use carbonate δ18O and δ13C systematics, combined with analyses of rock and fluid inclusion mineralogy and geochemistry, to investigate the alteration of the exhumed Eocene Cycladic subduction complex on the Syros and Tinos islands, Greece. We find that in marble rocks adjacent to two fluid conduits that were active during subduction, the abundance of calcium carbonate drastically decreases approaching the conduits, whereas silicate minerals increase. Up to 60-90% of the CO2 was released from the rocks--far greater than expected via simple devolatilization reactions. The δ18O of the carbonate minerals is 5-10 lighter than is typical for metamorphosed carbonate rocks, implying that isotopically light oxygen was transported by fluid infiltration from the surroundings. We suggest that fluid-mediated carbonate mineral removal, accompanied by silicate mineral precipitation, provides a mechanism for the release of enormous amounts of CO2 from subduction zones.
The effect of supplemental oral phosphate on the bone mineral changes during prolonged bed rest
Hulley, Stephen B.; Vogel, John M.; Donaldson, Charles L.; Bayers, Jon H.; Friedman, Ronald J.; Rosen, Sheldon N.
1971-01-01
Five healthy young men were studied during 24-30 wk of continuous bed rest. During the first 12 wk of bed rest, untreated subjects increased calcium excretion in the urine by 109 mg/day and in the feces by 147 mg/day. The rate of total body calcium loss was 0.5-0.7% per month. Losses of central calcaneus mineral, assessed by gamma ray transmission scanning, occurred at a tenfold higher rate, whereas the mineral content of the radius did not change. Changes in phosphorus balance resembled the calcium pattern, and increased excretion of nitrogen and hydroxyproline also occurred during bed rest. Upon reambulation, the subjects' calcium balance became positive in 1 month and recovery of their calcaneus mineral was complete within 10-20 wk. Treatment with potassium phosphate supplements (1327 mg P/day) entirely prevented the hypercalciuria of bed rest, but fecal calcium tended to increase. During the first 12 wk, calcium balance was slightly less negative (mean - 193 mg/day) than during bed rest without added phosphate (mean - 267 mg/day). This effect was not seen during the second 12 wk of bed rest. The patterns of magnesium excretion were similar to those of calcium. Fecal and urinary phosphorus excretions were doubled, and phosphorus balance became positive (+ 113 mg/day). Mineral loss from the central calcaneus was similar to that of untreated subjects. It is concluded that this form of phosphate supplementation reduces urinary calcium excretion but does not prevent bone loss during bed rest. PMID:5129304
Complementary effects of multi-protein components on biomineralization in vitro
Ba, Xiaolan; Rafailovich, Miriam; Meng, Yizhi; Pernodet, Nadine; Wirick, Sue; Füredi-Milhofer, Helga; Qin, Yi-Xian; DiMasi, Elaine
2016-01-01
The extracellular matrix (ECM) is composed of mixed protein fibers whose precise composition affects biomineralization. New methods are needed to probe the interactions of these proteins with calcium phosphate mineral and with each other. Here we follow calcium phosphate mineralization on protein fibers self-assembled in vitro from solutions of fibronectin, elastin and their mixture. We probe the surface morphology and mechanical properties of the protein fibers during the early stages. The development of mineral crystals on the protein matrices is also investigated. In physiological mineralization solution, the elastic modulus of the fibers in the fibronectin-elastin mixture increases to a greater extent than that of the fibers from either pure protein. In the presence of fibronectin, longer exposure in the mineral solution leads to the formation of amorphous calcium phosphate particles templated along the self-assembled fibers, while elastin fibers only collect calcium without any mineral observed during early stage. TEM images confirm that small needle-shape crystals are confined inside elastin fibers which suppress the release of mineral outside the fibers during late stage, while hydroxyapatite crystals form when fibronectin is present. These results demonstrate complementary actions of the two ECM proteins fibronectin and elastin to collect cations and template mineral, respectively. PMID:20035875
Influence of calcite and dissolved calcium on uranium(VI) sorption to a hanford subsurface sediment.
Dong, Wenming; Ball, William P; Liu, Chongxuan; Wang, Zheming; Stone, Alan T; Bai, Jing; Zachara, John M
2005-10-15
The influence of calcite and dissolved calcium on U(VI) adsorption was investigated using a calcite-containing sandy silt/clay sediment from the U. S. Department of Energy Hanford site. U(VI) adsorption to sediment, treated sediment, and sediment size fractions was studied in solutions that both had and had not been preequilibrated with calcite, at initial [U(VI)] = 10(-7)-10(-5) mol/L and final pH = 6.0-10.0. Kinetic and reversibility studies (pH 8.4) showed rapid sorption (30 min), with reasonable reversibility in the 3-day reaction time. Sorption from solutions equilibrated with calcite showed maximum U(VI) adsorption at pH 8.4 +/- 0.1. In contrast, calcium-free systems showed the greatest adsorption at pH 6.0-7.2. At pH > 8.4, U(VI) adsorption was identical from calcium-free and calcium-containing solutions. For calcite-presaturated systems, both speciation calculations and laser-induced fluorescence spectroscopic analyses indicated that aqueous U(VI) was increasingly dominated by Ca2UO2(CO3)3(0)(aq) at pH < 8.4 and thatformation of Ca2UO2(CO3)3(0)(aq) is what suppresses U(VI) adsorption. Above pH 8.4, aqueous U(VI) speciation was dominated by UO2(CO3)3(4-) in all solutions. Finally, results also showed that U(VI) adsorption was additive in regard to size fraction but not in regard to mineral mass: Carbonate minerals may have blocked U(VI) access to surfaces of higher sorption affinity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nakamura, K.
1972-01-01
Deficiency of available food material due either to poor diet or to malabsorption may adversely affect the skeleton. To study the affection, DDN mice were fed low calcium diet to induce low calcium state corresponding to malabsorption of calcium from the intestine. The femur was fractured manually. Then, calcium deposition in the callus was observed by microradiography and tracer technics with /sup 47/Ca. Increase of the body weight in mice fed low calcium diet was much slower than in the control. The affection of the low calcium diet on bone tissue appeared as a decrease of precipitation of calcium salt.more » This tendency was also observed in callus, Tracer study with /sup 47/Ca was performed in mice fed the low calcium diet for 24 days. Incorporation activity of calcium was generally high in each organ except the kidney. Callus in the site of the fracture in mice fed a low calcium diet was formed to the same degree as the control, although the amount of precipitated calcium in it was significantly poorer. In summary, insufficient mineralization in relation to osteogenesis occurred when the supply of the requisite electrolytes was insufficient or inappropriate. On the other hand, the uptake rate of calcinm in the callus was elevated even in the calcium deficient state. (auth)« less
Hydrochemical characterization of groundwater in the Akyem area, Ghana
Banoeng-Yakubo, B.; Yidana, S.M.; Anku, Y.; Akabzaa, T.; Asiedu, D.
2008-01-01
The Akyem area is a small farming community located in southeastern Ghana. Groundwater samples from wells in the area were analyzed for concentrations of the major ions, silica, electrical conductivity and pH. The objective was to determine the main controls on the hydrochemistry of ground-water. Mass balance modeling was used together with multivariate R-mode hierarchical cluster analysis to determine the significant sources of variation in the hydrochemistry. Two water types exist in this area. The first is influenced most by the weathering of silicate minerals from the underlying geology, and is thus rich in silica, sodium, calcium, bicarbonate, and magnesium ions. The second is water that has been influenced by the effects of fertilizers and other anthropogenic activities in the area. Mineral speciation and silicate mineral stability diagrams suggest that montmorillonite, probably derived from the incongruent dissolution of feldspars and micas, is the most stable silicate phase in the groundwaters. The apparent incongruent weathering of silicate minerals in the groundwater system has led to the enrichment of sodium, calcium, magnesium and bicarbonate ions as well as silica, leading to the supersaturation of calcite, aragonite, dolomite and quartz. Stability in the montmorillonite field suggests restricted flow conditions and a long groundwater residence time, leading to greater exposure of the rock to weathering. Cation exchange processes appear to play minor roles in the hydrochemistry of groundwater.
NASA Astrophysics Data System (ADS)
Moyo, Mack; Amoo, Stephen O.; Aremu, Adeyemi O.; Gruz, Jiri; Šubrtová, Michaela; Jarošová, Monika; Tarkowski, Petr; Doležal, Karel
2017-12-01
The study compared mineral, chemical and antioxidant qualities of Cleome gynandra, a wild leafy vegetable, with two widely consumed commercial vegetables; Brassica oleracea and Beta vulgaris. Mineral nutrients were quantified with inductively coupled plasma mass spectrometry (ICP-MS), phenolic compounds using ultra-high performance liquid chromatography coupled to a mass spectrometer (UHPLC-MS) and β-carotene and vitamin C using high performance liquid chromatography with a photodiode array detector (HPLC-PDA). The antioxidant potential was evaluated using 2,2–diphenyl–1–picryl hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC). Cleome gynandra had highest concentrations of phosphorus, potassium, calcium, iron, zinc, ascorbic acid, total phenolics and flavonoids; whereas sodium, magnesium, manganese, copper and β-carotene were higher in Beta vulgaris. The significantly higher antioxidant activity (P ≤ 0.05) exhibited by Cleome gynandra in comparison to the two commercial vegetables may be due to its significantly high levels of vitamin C and phenolic acids. These findings on the mineral, chemical and antioxidant properties of Cleome gynandra provide compelling scientific evidence of its potential in adding diversity to our diet and contributing towards the daily nutritional requirements of millions of people for food and nutritional security.
Mineral balance and bone turnover in adolescents with anorexia nervosa.
Abrams, S A; Silber, T J; Esteban, N V; Vieira, N E; Stuff, J E; Meyers, R; Majd, M; Yergey, A L
1993-08-01
We evaluated seven female adolescents with anorexia nervosa to determine whether calcium metabolism was affected by their disorder. We measured calcium absorption, urinary calcium excretion, and calcium kinetics, using a dual-tracer, stable-isotope technique during the first weeks of an inpatient nutritional rehabilitation program. Results were compared with those from a control group of seven healthy adolescent girls of similar ages. The percentage of absorption of calcium was lower in subjects with anorexia nervosa than in control subjects (16.2% +/- 6.3% vs 24.6% +/- 7.2%; p < 0.05). Urinary calcium excretion was greater in subjects with anorexia nervosa than in control subjects (6.4 +/- 2.5 vs 1.6 +/- 0.7 mg.kg-1 x day-1; p < 0.01) and was associated with bone resorption rather than calcium hyper-absorption. Calcium kinetic studies demonstrated a decreased rate of bone formation and an increased rate of bone resorption. These results suggest marked abnormalities in mineral metabolism in patients with anorexia nervosa. From these results, we hypothesize that improvement in bone mineralization during recovery from anorexia nervosa will require resolution of hormonal abnormalities, including hypercortisolism, in addition to increased calcium intake.
ERIC Educational Resources Information Center
Hemayattalab, Rasool
2010-01-01
The purpose of this study was to investigate the effects of physical training and calcium intake on bone mineral density (BMD) of students with mental retardation. Forty mentally retarded boys (age 7-10 years old) were randomly assigned to four groups (no differences in age, BMD, calcium intake and physical activity): training groups with or…
Building osteoporosis prevention into dental practice.
Stewart, Stacey; Hanning, Rhona
2012-01-01
The National Report Card on Osteoporosis Care (2008) announced the need for comprehensive approaches to risk reduction and improvement in the early diagnosis of osteoporosis. Dental research has suggested that low systemic bone-mineral density also occurs in alveolar bone, and people with osteoporosis may have an increased risk of tooth loss. Whether or not a causal link exists, both conditions share similar modifiable risk factors, including a role for calcium and vitamin D. The purpose of this paper was to critically examine the role calcium and vitamin D play in the relationship between osteoporosis and the risk of tooth loss. Scientific articles were obtained through PubMed, MEDLINE, CINAHL, AgeLine and Web of Science. Publications were restricted to those involving human subjects, and English-language articles on calcium and vitamin D. The search yielded 8 articles relating to osteoporosis and tooth loss that included calcium and vitamin D intake. Despite methodological concerns, the evidence shows a relationship between osteoporosis and tooth loss for people who have an inadequate intake of calcium and vitamin D. Adequate calcium intake positively influences optimal peak bone mass and may also assist in tooth retention in later life. The dental sector can assist with national prevention strategies for osteoporosis care.
Close-up View of Homestake Vein
2011-12-07
This close-up view of a mineral vein called Homestake comes from the microscopic imager on NASA Mars Exploration Rover Opportunity; the vein is found to be rich in calcium and sulfur, possibly the calcium-sulfate mineral gypsum.
Dietary supplement use is associated with higher intakes of minerals from food sources1234
Fulgoni, Victor L; Keast, Debra R; Dwyer, Johanna T
2011-01-01
Background: Dietary supplement use is extensive in US adults. Some reports suggested that supplement users had higher nutrient intakes from the diet than did nonusers, but to our knowledge this finding has not been examined in nationally representative survey data. Objective: In this analysis, we examined mineral intakes from the diet by supplement-use categories and how these supplements contributed to meeting or exceeding Dietary Reference Intakes for selected minerals. Design: Data from adults (≥19 y of age; n = 8860) who participated in NHANES 2003–2006, a nationally representative, cross-sectional survey, were examined. Supplement use was defined as the participant's self-reported use of a supplement that contained one or more selected minerals. Results: Dietary intakes of minerals from food sources were higher for magnesium, copper, potassium, and selenium in male supplement users than in nonusers. For women, dietary intakes of minerals from food sources were higher for users than for nonusers for each mineral examined except for selenium. In women, users of calcium-containing dietary supplements were much more likely to meet the Estimated Average Requirement (EAR) than were nonusers. Even after consideration of supplement use, >14% of adults had inadequate intakes for calcium and magnesium on the basis of the percentage of adults with usual intakes less than the EAR. The prevalence of adults who exceeded the tolerable upper intake level (UL) for calcium, zinc, iron, and magnesium was higher in users than in nonusers. Conclusions: Individuals who used mineral-containing dietary supplements had higher mineral intakes from food sources in the diet than did nonusers. For all minerals examined, and particularly for calcium and magnesium in men and women and iron in women, supplement use decreased the prevalence of intake inadequacy for each respective mineral; however, supplements contributed to risk of potentially excessive intakes for calcium, iron, zinc, and magnesium. PMID:21955646
Ercole, Claudia; Cacchio, Paola; Botta, Anna Lucia; Centi, Valeria; Lepidi, Aldo
2007-02-01
Bacterially induced carbonate mineralization has been proposed as a new method for the restoration of limestones in historic buildings and monuments. We describe here the formation of calcite crystals by extracellular polymeric substances isolated from Bacillus firmus and Bacillus sphaericus. We isolated bacterial outer structures (glycocalix and parietal polymers), such as exopolysaccharides (EPS) and capsular polysaccharides (CPS) and checked for their influence on calcite precipitation. CPS and EPS extracted from both B. firmus and B. sphaericus were able to mediate CaCO3 precipitation in vitro. X-ray microanalysis showed that in all cases the formed crystals were calcite. Scanning electron microscopy showed that the shape of the crystals depended on the fractions utilized. These results suggest the possibility that biochemical composition of CPS or EPS influences the resulting morphology of CaCO3. There were no precipitates in the blank samples. CPS and EPS comprised of proteins and glycoproteins. Positive alcian blue staining also reveals acidic polysaccharides in CPS and EPS fractions. Proteins with molecular masses of 25-40 kDa and 70 kDa in the CPS fraction were highly expressed in the presence of calcium oxalate. This high level of synthesis could be related to the binding of calcium ions and carbonate deposition.
Liang, Jianfen; Han, Bei-Zhong; Nout, M J Robert; Hamer, Robert J
2010-02-01
In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and [PA]/[Fe] and [PA]/[Zn] similarly ranged between 5 and 74, with most values between 20 and 30. [PA]/[mineral] molar ratios in intensively processed products were lower. Solubility of calcium ranged from 0% to 87%, with the lowest in brown rice (12%) and the highest in infant foods (50%). Iron solubility in two-thirds of samples was lower than 30%, and that of zinc narrowly ranged from 6% to 30%. Solubility of minerals was not significantly affected by [PA]/[mineral]. At present, neither primary nor intensively processed rice-based products are good dietary sources of minerals. Improvements should be attempted by dephytinization, mineral fortification or, preferably, combination of both.
NASA Technical Reports Server (NTRS)
Ross, M. D.; Pote, K. G.; Rarey, K. E.; Verma, L. M.
1981-01-01
The gravity receptors of all vertebrates utilize a 'test mass' consisting of a complex arrangement of mineral and organic substance that lies over the sensory receptor areas. In most vertebrates, the mineral is a polymorph of calcium carbonate in the form of minute, single crystals called otoconia. An investigation is conducted to determine the number of proteins in otoconial complexes and their molecular weights. The investigation makes use of a microdisk gel electrophoresis method reported by Gainer (1971). The most important finding of the reported research is that analysis of the proteins of the organic material of the otoconial complexes is possible when sensitive microanalytical methods are employed. Further modification of the basic technique employed and the inclusion of other sensitive staining methods should mean that, in the future, protein separation by molecular weight will be possible in sample pools containing only two otoconial masses.
High Dietary Protein Intake and Protein-Related Acid Load on Bone Health.
Cao, Jay J
2017-12-01
Consumption of high-protein diets is increasingly popular due to the benefits of protein on preserving lean mass and controlling appetite and satiety. The paper is to review recent clinical research assessing dietary protein on calcium metabolism and bone health. Epidemiological studies show that long-term, high-protein intake is positively associated with bone mineral density and reduced risk of bone fracture incidence. Short-term interventional studies demonstrate that a high-protein diet does not negatively affect calcium homeostasis. Existing evidence supports that the negative effects of the acid load of protein on urinary calcium excretion are offset by the beneficial skeletal effects of high-protein intake. Future research should focus on the role and the degree of contribution of other dietary and physiological factors, such as intake of fruits and vegetables, in reducing the acid load and further enhancing the anabolic effects of protein on the musculoskeletal system.
Bae, Yun Jung; Bu, So Young; Kim, Jae Young; Yeon, Jee-Young; Sohn, Eun-Wha; Jang, Ki-Hyo; Lee, Jae-Cheol; Kim, Mi-Hyun
2011-12-01
Commercially available seaweed calcium extract can supply high amounts of calcium as well as significant amounts of magnesium and other microminerals. The purpose of this study was to investigate the degree to which the high levels of magnesium in seaweed calcium extract affects the calcium balance and the bone status in ovariectomized rats in comparison to rats supplemented with calcium carbonate and magnesium oxide. A total of 40 Sprague-Dawley female rats (7 weeks) were divided into four groups and bred for 12 weeks: sham-operated group (Sham), ovariectomized group (OVX), ovariectomized with inorganic calcium and magnesium supplementation group (OVX-Mg), and ovariectomized with seaweed calcium and magnesium supplementation group (OVX-SCa). All experimental diets contained 0.5% calcium. The magnesium content in the experimental diet was 0.05% of the diet in the Sham and OVX groups and 0.1% of the diet in the OVX-Mg and OVX-SCa groups. In the calcium balance study, the OVX-Mg and OVX-SCa groups were not significantly different in calcium absorption compared to the OVX group. However, the femoral bone mineral density and strength of the OVX-SCa group were higher than those of the OVX-Mg and OVX groups. Seaweed calcium with magnesium supplementation or magnesium supplementation alone did not affect the serum ALP and CTx levels in ovariectomized rats. In summary, consumption of seaweed calcium extract or inorganic calcium carbonate with magnesium oxide demonstrated the same degree of intestinal calcium absorption, but only the consumption of seaweed calcium extract resulted in increased femoral bone mineral density and strength in ovariectomized rats. Our results suggest that seaweed calcium extract is an effective calcium and magnesium source for improving bone health compared to synthetic calcium and magnesium supplementation.
Nutritional status among postmenopausal osteoporotic women in North West of Iran.
Hejazi, Jalal; Mohtadinia, Javad; Kolahi, Sousan; Ebrahimi-Mamaghani, Mehrangiz
2009-01-01
Osteoporosis is a multifactorial disease and one of the most important modifiable factors in the development and maintenance of bone mass is nutrition. The aim of this study was to determine the nutritional status among osteoporotic postmenopausal women in north west of Iran and compare intake of several nutrients important in terms of bone health with the standard values (DRIs). Bone mineral density of the left proximal femur, the lumbar spine and total hip were measured using dual-energy X-ray absorptiometry. Ninety-seven postmenopausal osteoporotic women were studied. A validated food frequency questionnaire was used to determine food habits and 24-h recall was used to estimate average energy and nutrient intakes. The mean t-score for bone mineral density (BMD) of LS, FN and total hip were -3.15 +/- 0.73, -1.93 +/- 0.86 and -1.92 +/- 0.88, respectively. The percentages of participants receiving adequate intake of calcium, vitamin D and vitamin K were 7.2%, 3.1% and 42.3%, respectively. The mean phosphate to calcium ratio was 1.6 +/- 0.87. BMD of femoral neck and total hip was correlated inversely with the amount of energy obtained from fat and positively with energy intake. Among micronutrients studied, calcium was positively correlated with BMD of total hip. Most of the postmenopausal osteoporotic women in north west of Iran have a considerable deficiency in terms of energy and some micronutrients such as calcium, vitamin D and magnesium, which can be deleterious for bone health.
Murad, Rafat; Shezad, Zahra; Ahmed, Saara; Ashraf, Mussarat; Qadir, Murad; Rehman, Rehana
2018-03-01
To compare biochemical parameters serum tumour necrosis factor alpha, calcium, magnesium, bone-specific alkaline phosphatase and vitamin D in postmenopausal women. This cross-sectional study was carried out from June 2015 to July 2016 at Jinnah Medical and Dental College, Karachi, and comprised postmenopausal women. Bone mineral density done by dual energy X-ray absorptiometryscan categorised subjects by World Health Organisation classification into normal (T score > -1) osteopenic (T score between -1 and -2.5) and osteoporotic (T score < -2.5). Biochemical parameters like tumour necrosis alpha, calcium, magnesium, bone-specific alkaline phosphatase and vitamin D were measured by solid phase enzyme amplified sensitivity immunoassay method. SPSS 16 was used to analyse the data. Of the 146 women, 34(23%) were normal, 93(67%) were osteopenic and 19(13%) were osteoporotic. There was significant difference in mean body mass index, serum tumour necrosis factor alpha and calcium in all the three groups (p<0.01). Significant mean difference was observed in serum calcium levels between normal and osteopenic, and between normal and osteoporotic group (p<0.05 each) without any significant mean difference between osteopenic and osteoporotic groups (p>0.05). A significant difference was observed for mean tumour necrosis factor alpha values between normal and osteoporotic groups (p<0.05). Tumour necrosis factor alpha showed negative correlation with bone mineral density in osteopenic and osteoporotic groups (p>0.05). Increased bone turnover in postmenopausal osteopenic women can be predicted by increased serum cytokine.
Intestinal Calcium Absorption among Hypercalciuric Patients with or without Calcium Kidney Stones.
Vezzoli, Giuseppe; Macrina, Lorenza; Rubinacci, Alessandro; Spotti, Donatella; Arcidiacono, Teresa
2016-08-08
Idiopathic hypercalciuria is a frequent defect in calcium kidney stone formers that is associated with high intestinal calcium absorption and osteopenia. Characteristics distinguishing hypercalciuric stone formers from hypercalciuric patients without kidney stone history (HNSFs) are unknown and were explored in our study. We compared 172 hypercalciuric stone formers with 36 HNSFs retrospectively selected from patients referred to outpatient clinics of the San Raffaele Hospital in Milan from 1998 to 2003. Calcium metabolism and lumbar bone mineral density were analyzed in these patients. A strontium oral load test was performed: strontium was measured in 240-minute urine and serum 30, 60, and 240 minutes after strontium ingestion; serum strontium concentration-time curve and renal strontium clearance were evaluated to estimate absorption and excretion of divalent cations. Serum strontium concentration-time curve (P<0.001) and strontium clearance (4.9±1.3 versus 3.5±2.7 ml/min; P<0.001) were higher in hypercalciuric stone formers than HNSFs, respectively. The serum strontium-time curve was also higher in hypercalciuric stone formers with low bone mineral density (n=42) than in hypercalciuric stone formers with normal bone mineral density (n=130; P=0.03) and HNSFs with low (n=22; P=0.01) or normal bone mineral density (n=14; P=0.02). Strontium clearance was greater in hypercalciuric stone formers with normal bone mineral density (5.3±3.4 ml/min) than in hypercalciuric stone formers and HNSFs with low bone mineral density (3.6±2.5 and 3.1±2.5 ml/min, respectively; P=0.03). Multivariate regression analyses displayed that strontium absorption at 30 minutes was positively associated calcium excretion (P=0.03) and negatively associated with lumbar bone mineral density z score (P=0.001) in hypercalciuric stone formers; furthermore, hypercalciuric patients in the highest quartile of strontium absorption had increased stone production risk (odds ratio, 5.06; 95% confidence interval, 1.2 to 20.9; P=0.03). High calcium absorption in duodenum and jejunum may expose hypercalciuric patients to the risk of stones because of increased postprandial calcium concentrations in urine and tubular fluid. High calcium absorption may identify patients at risk of bone loss among stone formers. Copyright © 2016 by the American Society of Nephrology.
Tassinary, João Alberto Fioravante; Lunardelli, Adroaldo; Basso, Bruno de Souza; Dias, Henrique Bregolin; Catarina, Anderson Velasque; Stülp, Simone; Haute, Gabriela Viegas; Martha, Bianca Andrade; Melo, Denizar Alberto da Silva; Nunes, Fernanda Bordignon; Donadio, Márcio Vinícius Fagundes; Oliveira, Jarbas Rodrigues de
2018-03-01
The present study aimed to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on pre-osteoblast mineralization using in vitro bioassays. Pre-osteoblastic MC3T3-E1 cells were exposed to LIPUS at 1 MHz frequency, 0.2 W/cm 2 intensity and 20% duty cycle for 30 min. The analyses were carried out up to 336 h (14 days) after exposure. The concentration of collagen, phosphate, alkaline phosphatase, calcium and transforming growth factor beta 1 (TGF-β1) in cell supernatant and the presence of calcium deposits in the cells were analyzed. Our results showed that LIPUS promotes mineralized nodules formation. Collagen, phosphate, and calcium levels were decreased in cell supernatant at 192 h after LIPUS exposure. However, alkaline phosphatase and TGF-β1 concentrations remained unchanged. Therapeutic pulsed ultrasound is capable of stimulating differentiation and mineralization of pre-osteoblastic MC3T3-E1 cells by calcium and phosphate uptake with consequent hydroxyapatite formation. Copyright © 2017 Elsevier B.V. All rights reserved.
Biomimetic Mineralization on a Macroporous Cellulose-Based Matrix for Bone Regeneration
Petrauskaite, Odeta; Gomes, Pedro de Sousa; Fernandes, Maria Helena; Juodzbalys, Gintaras; Maminskas, Julius
2013-01-01
The aim of this study is to investigate the biomimetic mineralization on a cellulose-based porous matrix with an improved biological profile. The cellulose matrix was precalcified using three methods: (i) cellulose samples were treated with a solution of calcium chloride and diammonium hydrogen phosphate; (ii) the carboxymethylated cellulose matrix was stored in a saturated calcium hydroxide solution; (iii) the cellulose matrix was mixed with a calcium silicate solution in order to introduce silanol groups and to combine them with calcium ions. All the methods resulted in a mineralization of the cellulose surfaces after immersion in a simulated body fluid solution. Over a period of 14 days, the matrix was completely covered with hydroxyapatite crystals. Hydroxyapatite formation depended on functional groups on the matrix surface as well as on the precalcification method. The largest hydroxyapatite crystals were obtained on the carboxymethylated cellulose matrix treated with calcium hydroxide solution. The porous cellulose matrix was not cytotoxic, allowing the adhesion and proliferation of human osteoblastic cells. Comparatively, improved cell adhesion and growth rate were achieved on the mineralized cellulose matrices. PMID:24163816
Natural calcium isotonic composition of urine as a marker of bone mineral balance
Skulan, J.; Bullen, T.; Anbar, A.D.; Puzas, J.E.; Shackelford, L.; LeBlanc, A.; Smith, S.M.
2007-01-01
Background: We investigated whether changes in the natural isotopic composition of calcium in human urine track changes in net bone mineral balance, as predicted by a model of calcium isotopic behavior in vertebrates. If so, isotopic analysis of natural urine or blood calcium could be used to monitor short-term changes in bone mineral balance that cannot be detected with other techniques. Methods: Calcium isotopic compositions are expressed as ??44Ca, or the difference in parts per thousand between the 44Ca/40Ca of a sample and the 44Ca/ 40Ca of a standard reference material. ??44Ca was measured in urine samples from 10 persons who participated in a study of the effectiveness of countermeasures to bone loss in spaceflight, in which 17 weeks of bed rest was used to induce bone loss. Study participants were assigned to 1 of 3 treatment groups: controls received no treatment, one treatment group received alendronate, and another group performed resistive exercise. Measurements were made on urine samples collected before, at 2 or 3 points during, and after bed rest. Results: Urine ??44Ca values during bed rest were lower in controls than in individuals treated with alendronate (P <0.05, ANOVA) or exercise (P <0.05), and lower than the control group baseline (P <0.05, Mest). Results were consistent with the model and with biochemical and bone mineral density data. Conclusion: Results confirm the predicted relationship between bone mineral balance and calcium isotopes, suggesting that calcium isotopic analysis of urine might be refined into a clinical and research tool. ?? 2007 American Association for Clinical Chemistry.
Natural calcium isotopic composition of urine as a marker of bone mineral balance.
Skulan, Joseph; Bullen, Thomas; Anbar, Ariel D; Puzas, J Edward; Shackelford, Linda; LeBlanc, Adrian; Smith, Scott M
2007-06-01
We investigated whether changes in the natural isotopic composition of calcium in human urine track changes in net bone mineral balance, as predicted by a model of calcium isotopic behavior in vertebrates. If so, isotopic analysis of natural urine or blood calcium could be used to monitor short-term changes in bone mineral balance that cannot be detected with other techniques. Calcium isotopic compositions are expressed as delta(44)Ca, or the difference in parts per thousand between the (44)Ca/(40)Ca of a sample and the (44)Ca/(40)Ca of a standard reference material. delta(44)Ca was measured in urine samples from 10 persons who participated in a study of the effectiveness of countermeasures to bone loss in spaceflight, in which 17 weeks of bed rest was used to induce bone loss. Study participants were assigned to 1 of 3 treatment groups: controls received no treatment, one treatment group received alendronate, and another group performed resistive exercise. Measurements were made on urine samples collected before, at 2 or 3 points during, and after bed rest. Urine delta(44)Ca values during bed rest were lower in controls than in individuals treated with alendronate (P <0.05, ANOVA) or exercise (P <0.05), and lower than the control group baseline (P <0.05, t-test). Results were consistent with the model and with biochemical and bone mineral density data. Results confirm the predicted relationship between bone mineral balance and calcium isotopes, suggesting that calcium isotopic analysis of urine might be refined into a clinical and research tool.
Interaction of zinc with dental mineral.
Ingram, G S; Horay, C P; Stead, W J
1992-01-01
As some currently available toothpastes contain zinc compounds, the reaction of zinc with dental mineral and its effect on crystal growth rates were studied using three synthetic calcium-deficient hydroxyapatites (HAP) as being representative of dental mineral. Zinc was readily acquired by all HAP samples in the absence of added calcium, the amount adsorbed being proportional to the HAP surface area; about 9 mumol Zn/m2 was adsorbed at high zinc concentrations. As zinc was acquired, calcium was released, consistent with 1:1 Ca:Zn exchange. Soluble calcium reduced zinc uptake and similarly, calcium post-treatment released zinc. Pretreatment of HAP with 0.5 mM zinc reduced its subsequent ability to undergo seeded crystal growth, as did extracts of a toothpaste containing 0.5% zinc citrate, even in the presence of saliva. The reverse reaction, i.e. displacement of adsorbed zinc by salivary levels of calcium, however, indicates the mechanism by which zinc can reduce calculus formation in vivo by inhibiting plaque mineralisation without adversely affecting the anti-caries effects of fluoride.
ERIC Educational Resources Information Center
Goodarzi, Mahmood; Hemayattalab, Rasool
2012-01-01
The purpose of this study was to investigate the effects of weight bearing exercise and calcium intake on bone mineral density (BMD) of students with autism spectrum disorders. For this reason 60 boy students with autism disorder (age 8-10 years old) were assigned to four groups with no differences in age, BMD, calcium intake, and physical…
Using stable isotope tracers to study bone metabolism in children.
O'Brien, Kimberly O; Abrams, Steven A
2018-06-05
Skeletal mineralization is initiated in utero and continues throughout childhood and adolescence. During these key periods of the life cycle calcium retention must increase significantly to provide sufficient mineral for bone deposition and skeletal growth. Stable calcium isotopes have served as a fundamental tool to non-invasively characterize the dynamic changes in calcium physiology that occur from infancy through adolescence. These approaches have helped define the dynamics of calcium absorption and utilization in healthy children and in children with chronic diseases. As data in this area have accumulated, new areas of emphasis are beginning to characterize the determinants of variability in mineral retention, the genetic determinants of bone turnover and calcium flux and the impact of the gut microbiome on whole body and niche specific calcium dynamics. Advances in these areas will help define calcium utilization in pediatric populations and provide information that may be useful in maximizing bone acquisition across this critical phase of the life cycle. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Vibrational spectroscopic study of poldervaartite CaCa[SiO3(OH)(OH)
NASA Astrophysics Data System (ADS)
Frost, Ray L.; López, Andrés; Scholz, Ricardo; Lima, Rosa Malena Fernandes
2015-02-01
We have studied the mineral poldervaartite CaCa[SiO3(OH)(OH)] which forms a series with its manganese analogue olmiite CaMn[SiO3(OH)](OH) using a range of techniques including scanning electron microscopy, thermogravimetric analysis, Raman and infrared spectroscopy. Chemical analysis shows the mineral is reasonably pure and contains only calcium and manganese with low amounts of Al and F. Thermogravimetric analysis proves the mineral decomposes at 485 °C with a mass loss of 7.6% compared with the theoretical mass loss of 7.7%. A strong Raman band at 852 cm-1 is assigned to the SiO stretching vibration of the SiO3(OH) units. Two Raman bands at 914 and 953 cm-1 are attributed to the antisymmetric vibrations. Intense prominent peaks observed at 3487, 3502, 3509, 3521 and 3547 cm-1 are assigned to the OH stretching vibration of the SiO3(OH) units. The observation of multiple OH bands supports the concept of the non-equivalence of the OH units. Vibrational spectroscopy enables a detailed assessment of the molecular structure of poldervaartite.
Combat sports practice favors bone mineral density among adolescent male athletes.
Nasri, Raouf; Hassen Zrour, Saoussen; Rebai, Haithem; Neffeti, Fadoua; Najjar, Mohamed Fadhel; Bergaoui, Naceur; Mejdoub, Hafedh; Tabka, Zouhair
2015-01-01
The aim of this study was to determine the impact of combat sports practice on bone mineral density (BMD) and to analyze the relationship between bone parameters and anthropometric measurements, bone markers, and activity index (AI). In other words, to detect the most important determinant of BMD in the adolescent period among combat sports athletes. Fifty athletes engaged in combat sports, mean age 17.1±0.2 yr, were compared with 30 sedentary subjects who were matched for age, height, and pubertal stage. For all subjects, the whole-body BMD, lumbar spine BMD (L2-L4), and BMD in the pelvis, arms, and legs was measured by dual-energy X-ray absorptiometry, and anthropometric measurements were evaluated. Daily calcium intake, bone resorption, and formation markers were measured. BMD measurements were greater in the combat sports athletes than in the sedentary group (p<0.01). Weight, body mass index, and lean body mass were significantly correlated with BMD in different sites. Daily calcium consumption lower than daily calcium intake recommended in both athletes and sedentary group. AI was strongly correlated with all BMD measurements particularly with the whole body, legs, and arms. Negative correlations were observed between bone markers and BMD in different sites. The common major predictor of BMD measurements was AI (p<0.0001). AI associated to lean body mass determined whole-body BMD until 74%. AI explained both BMD in arms and L2-L4 at 25%. AI associated to height can account for 63% of the variance in BMD legs. These observations suggested that the best model predicting BMD in different sites among adolescent combat sports athletes was the AI. Children and adolescents should be encouraged to participate in combat sports to maximize their bone accrual. Copyright © 2015 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.
Mineral-bearing vesicle transport in sea urchin embryos.
Vidavsky, Netta; Masic, Admir; Schertel, Andreas; Weiner, Steve; Addadi, Lia
2015-12-01
Sea urchin embryos sequester calcium from the sea water. This calcium is deposited in a concentrated form in granule bearing vesicles both in the epithelium and in mesenchymal cells. Here we use in vivo calcein labeling and confocal Raman spectroscopy, as well as cryo-FIB-SEM 3D structural reconstructions, to investigate the processes occurring in the internal cavity of the embryo, the blastocoel. We demonstrate that calcein stained granules are also present in the filopodial network within the blastocoel. Simultaneous fluorescence imaging and Raman spectroscopy show that these granules do contain a calcium mineral. By tracking the movements of these granules, we show that the granules in the epithelium and primary mesenchymal cells barely move, but those in the filopodial network move long distances. We could however not detect any unidirectional movement of the filopodial granules. We also show the presence of mineral containing multivesicular vesicles that also move in the filopodial network. We conclude that the filopodial network is an integral part of the mineral transport process, and possibly also for sequestering calcium and other ions. Although much of the sequestered calcium is deposited in the mineralized skeleton, a significant amount is used for other purposes, and this may be temporarily stored in these membrane-delineated intracellular deposits. Copyright © 2015 Elsevier Inc. All rights reserved.
Calcium oxalate stone formation in the inner ear as a result of an Slc26a4 mutation.
Dror, Amiel A; Politi, Yael; Shahin, Hashem; Lenz, Danielle R; Dossena, Silvia; Nofziger, Charity; Fuchs, Helmut; Hrabé de Angelis, Martin; Paulmichl, Markus; Weiner, Steve; Avraham, Karen B
2010-07-09
Calcium oxalate stone formation occurs under pathological conditions and accounts for more than 80% of all types of kidney stones. In the current study, we show for the first time that calcium oxalate stones are formed in the mouse inner ear of a genetic model for hearing loss and vestibular dysfunction in humans. The vestibular system within the inner ear is dependent on extracellular tiny calcium carbonate minerals for proper function. Thousands of these biominerals, known as otoconia, are associated with the utricle and saccule sensory maculae and are vital for mechanical stimulation of the sensory hair cells. We show that a missense mutation within the Slc26a4 gene abolishes the transport activity of its encoded protein, pendrin. As a consequence, dramatic changes in mineral composition, size, and shape occur within the utricle and saccule in a differential manner. Although abnormal giant carbonate minerals reside in the utricle at all ages, in the saccule, a gradual change in mineral composition leads to a formation of calcium oxalate in adult mice. By combining imaging and spectroscopy tools, we determined the profile of mineral composition and morphology at different time points. We propose a novel mechanism for the accumulation and aggregation of oxalate crystals in the inner ear.
Calcium is one of the most important minerals for the growth, maintenance, and reproduction of the human ... body, are continually being re-formed and incorporate calcium into their structure. Calcium is essential for the ...
Zhao, Ai; Xue, Yong; Zhang, Yumei; Li, Wenjun; Yu, Kai; Wang, Peiyu
2016-01-01
Objectives of this study were 1) to investigate the mineral intake by Chinese lactating women, 2) to explore the dietary source of minerals, and 3) the ratios between different dietary minerals. A total of 468 lactating women in 5-240 days post-partum participated in this study. Food intakes by participants were measured using one time of 24-hour dietary recall, and minerals from food were calculated based on the Chinese Food Composition Table, second edition. In post-partum, women had inadequate food intake. 81.0% of women's daily intake of dairy products was lower than 300g, and 97.1% of women's daily intake of salt over 6g. For mineral intake, there were 81.8%, 59.0%, 47.6%, 45.7% and 66.8% of women's calcium, magnesium, iron, zinc and selenium intake lower than the estimated average requirement, respectively, and 91.7% of women's excessive intake of sodium. The calcium/phosphorus and sodium/potassium ratios were 0.41±0.26/1 and 3.13±2.89/1, respectively. Considering the dietary sources of minerals, 27.3%, 25.3% and 30.1% of iron, zinc and calcium were from animal-based food, respectively, and 60.3%, 66.1% and 58.0% of iron, zinc and calcium were from plant-based food, respectively. The phosphorus-protein ratio was 0.014±0.003/1. Lactation stage was associated with nutrient intake. Women within 30 days post-partum and the ones who live in Guangzhou had a significantly lower intake of certain minerals, while women with a high education experience had a high intake of calcium, potassium, iron and zinc. Productive age, whether obese or not, and delivery ways were not associated with mineral intakes (P all >0.05). Chinese women in three studied cities had an inappropriate food intake and resulted in both insufficient and excessive intakes of certain minerals.
Establishment of peak bone mass.
Mora, Stefano; Gilsanz, Vicente
2003-03-01
Among the main areas of progress in osteoporosis research during the last decade or so are the general recognition that this condition, which is the cause of so much pain in the elderly population, has its antecedents in childhood and the identification of the structural basis accounting for much of the differences in bone strength among humans. Nevertheless, current understanding of the bone mineral accrual process is far from complete. The search for genes that regulate bone mass acquisition is ongoing, and current results are not sufficient to identify subjects at risk. However, there is solid evidence that BMD measurements can be helpful for the selection of subjects that presumably would benefit from preventive interventions. The questions regarding the type of preventive interventions, their magnitude, and duration remain unanswered. Carefully designed controlled trials are needed. Nevertheless, previous experience indicates that weight-bearing activity and possibly calcium supplements are beneficial if they are begun during childhood and preferably before the onset of puberty. Modification of unhealthy lifestyles and increments in exercise or calcium assumption are logical interventions that should be implemented to improve bone mass gains in all children and adolescents who are at risk of failing to achieve an optimal peak bone mass.
Dhami, Navdeep K.; Mukherjee, Abhijit; Watkin, Elizabeth L. J.
2018-01-01
Natural mineral formations are a window into important processes leading to carbon storage and mineralized carbonate structures formed through abiotic and biotic processes. In the current study, we made an attempt to undertake a comprehensive approach to characterize the mineralogical, mechanical, and microbial properties of different kinds of speleothems from karstic caves; with an aim to understand the bio-geo-chemical processes in speleothem structures and their impact on nanomechanical properties. We also investigated the biomineralization abilities of speleothem surface associated microbial communities in vitro. Mineralogical profiling using techniques such as X-ray powder Diffraction (XRD) and Tescan Integrated Mineral Analyzer (TIMA) demonstrated that calcite was the dominant mineral in the majority of speleothems with Energy Dispersive X-ray Analysis (EDS) indicating a few variations in the elemental components. Differing proportions of polymorphs of calcium carbonate such as aragonite and vaterite were also recorded. Significant variations in trace metal content were recorded through Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Scanning Electron Microscopy (SEM) analysis revealed differences in morphological features of the crystals which varied from triangular prismatic shapes to etched spiky forms. Microbial imprints and associations were seen in a few sections. Analysis of the associated microbial diversity showed significant differences between various speleothems at Phylum level; although Proteobacteria and Actinobacteria were found to be the predominant groups. Genus level microbial associations showed a relationship with the geochemistry, mineralogical composition, and metal content of the speleothems. The assessment of nanomechanical properties measured by Nanoindentation revealed that the speleothems with a dominance of calcite were stronger than the speleothems with mixed calcium carbonate polymorphs and silica content. The in vitro metabolic activity of the microbial communities associated with the surfaces of the speleothems resulted in calcium carbonate crystal precipitation. Firmicutes and Proteobacteria dominated these populations, in contrast to the populations seen in natural systems. The precipitation of calcium carbonate crystals in vitro indicated that microbial metabolic activity may also play an important role in the synthesis and dissociation of biominerals in the natural environment. Our study provides novel evidence of the close relationship between mineralogy, microbial ecology, geochemistry, and nanomechanical properties of natural formations. PMID:29472898
Amorphous calcium carbonate transforms into calcite during sea urchin larval spicule growth
Beniash, E.; Aizenberg, J.; Addadi, L.; Weiner, S.
1997-01-01
Sea urchin larvae form an endoskeleton composed of a pair of spicules. For more than a century it has been stated that each spicule comprises a single crystal of the CaCO3 mineral, calcite. We show that an additional mineral phase, amorphous calcium carbonate, is present in the sea urchin larval spicule, and that this inherently unstable mineral transforms into calcite with time. This observation significantly changes our concepts of mineral formation in this well-studied organism.
ERIC Educational Resources Information Center
Arab ameri, Elahe; Dehkhoda, Mohammad Reza; Hemayattalab, Rasool
2012-01-01
In this study we investigate the effects of weight bearing exercise and calcium intake on bone mineral density (BMD) of students with attention deficit and hyper activity (ADHD) disorder. For this reason 54 male students with ADHD (age 8-12 years old) were assigned to four groups with no differences in age, BMD, calcium intake, and physical…
Meng, Z X; Li, H F; Sun, Z Z; Zheng, W; Zheng, Y F
2013-03-01
Surface mineralization is an effective method to produce calcium phosphate apatite coating on the surface of bone tissue scaffold which could create an osteophilic environment similar to the natural extracellular matrix for bone cells. In this study, we prepared mineralized poly(D,L-lactide-co-glycolide) (PLGA) and PLGA/gelatin electrospun nanofibers via depositing calcium phosphate apatite coating on the surface of these nanofibers to fabricate bone tissue engineering scaffolds by concentrated simulated body fluid method, supersaturated calcification solution method and alternate soaking method. The apatite products were characterized by the scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffractometry (XRD) methods. A large amount of calcium phosphate apatite composed of dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HA) and octacalcium phosphate (OCP) was deposited on the surface of resulting nanofibers in short times via three mineralizing methods. A larger amount of calcium phosphate was deposited on the surface of PLGA/gelatin nanofibers rather than PLGA nanofibers because gelatin acted as nucleation center for the formation of calcium phosphate. The cell culture experiments revealed that the difference of morphology and components of calcium phosphate apatite did not show much influence on the cell adhesion, proliferation and activity. Copyright © 2012 Elsevier B.V. All rights reserved.
Becker, Alexander; Ziegler, Andreas; Epple, Matthias
2005-05-21
The cuticules (shells) of the woodlice Porcellio scaber and Armadillidium vulgare were analysed with respect to their content of inorganic material. It was found that the cuticles consist of crystalline magnesium calcite, amorphous calcium carbonate (ACC), and amorphous calcium phosphate (ACP), besides small amounts of water and an organic matrix. It is concluded that the cuticle, which constitutes a mineralized protective organ, is chemically adapted to the biological requirements by this combination of different materials.
Benzaquen, M; Galvão, K N; Coleman, A E; Santos, J E P; Goff, J P; Risco, C A
2015-05-01
The objectives of this study were to determine the effect of mineral/energy supplementation of dairy cows with dystocia on blood mineral concentrations, energetic and inflammatory profiles, and milk yield. Multiparous Holstein cows with dystocia were randomly assigned into two groups, (1) treated with a mineral/energy supplement (DME, n= 18) and (2) not treated (DNT, n= 22). A group of cows with normal parturition were randomly selected and were left untreated (NNT, n= 25). Cows in DME received an oral drench of 110 g of calcium and 400 g of propionate as calcium propionate plus 110 g potassium chloride and 150 g of magnesium sulfate administered within 6 h of calving and again 3 days post-partum. Compared to cows with a normal parturition, dystocic cows had decreased plasma calcium concentrations, increased plasma haptoglobin, decreased milk yield at 1 day post-partum, and tended to have increased rectal temperatures from 1 to 12 days post-partum. Compared with cows in DNT, those in DME had decreased plasma calcium concentrations and increased plasma magnesium concentrations 2 and 3 days post-partum, and a tendency for an increase in rectal temperature from 1 to 12 days post-partum. Dystocia is detrimental to calcium homeostasis post-partum, but mineral/energy supplementation as undertaken in this study is not recommended for use in cows with dystocia. Copyright © 2015 Elsevier Ltd. All rights reserved.
... A calcium-rich diet (including dairy, nuts, leafy greens and fish) helps to build and protect your bones. Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our ...
Alkali Silica Reaction In The Presence Of Metakaolin - The Significant Role of Calcium Hydroxide
NASA Astrophysics Data System (ADS)
Zapała-Sławeta, Justyna
2017-10-01
Reducing the internal corrosion, which is the result of reactions between alkalis and reactive aggregates is especially important in ensuring durability properties of concrete. One of the methods of inhibiting the reaction is using some mineral additives which have pozzolanic properties. This paper presents the efficacy of high-reactivity metakaolin in reducing expansion due to alkali-silica reaction. It was demonstrated that metakaolin in the amount from 5% to 20% by mass of Portland cement reduce linear expansion of mortar bars with opal aggregate. Nevertheless, the safe expansion level in the specimens, classified as non-destructive to concrete, was recorded for the mortars prepared with 20% addition of metakaolin. Depletion of free calcium hydroxide content was considered as one of the most beneficial effects of metakaolin in controlling alkali silica reaction. Based on thermogravimetric analysis (TGA) performed on mortar bars with and without metakaolin the differences in portlandite content were determined. Microstructural observation of the specimens containing metakaolin indicated the presence of a reaction products but fewer in number than those forming in the mortars without mineral additives.
NASA Astrophysics Data System (ADS)
Dewi Kencana Wungu, Triati; Fauzan, Muhammad Rifqi Al; Widayani; Suprijadi
2016-08-01
In this study, we performed structural geometry and electronic properties calculations of calcium - based clay mineral for medicine application using first principles calculation by means of Density Functional Theory. Here, a kind of clay mineral used was Ca- montmorillonite and it is applied as an absorber of dangerous metal contained in a human body, such as Pb, which causes osteoporosis. Osteoporosis is a disease associated with bone mass decreases. Since montmorillonite has ability to exchange its cation (Ca+2), therefore, it plays an important role in preventing or/and cure human bone from osteoporosis. In order to understand how Ca-montmorillonite can do detoxification in the human body, we firstly investigated the mechanism of Pb adsorption on the surface of Ca-montmorillonite in an atomic level point of view. We found that the repulsive interactions between H of OH groups with Ca and Pb yielding the rotation of the H of OH groups of montmorillonite. A relatively small movement of Ca was observed when Pb is adsorbed and the band gap of Ca- montmorillonite becomes 1.87 eV narrow.
Application of electron probe X-ray microanalysis to calcification studies of bone and cartilage.
Landis, W J
1979-01-01
The use of electron probe x-ray microanalysis in previous studies of bone and cartilage has been reviewed with emphasis on the results which have contributed to some of the current concepts of the mechanism of mineralization in these tissues. A number of investigations continuing in the author's laboratory utilizing high spatial resolution x-ray microanalysis and anhydrous methods of specimen preparation are described, including aspects concerning the derivation of calibration curves from synthetic calcium phosphate solids, qualitative and quantitative analyses of calcium and phosphorus in bone from embryonic chicks and in growth plate cartilage from rats, and the role of organically-bound phosphorus in mineralizing tissues. The data obtained have helped identify brushite, CaHPO4-2H2O, as the major crystalline solid phase of calcium phosphate in the earliest mineral deposits of bone tissue, brushite and poorly crystalline hydroxyapatite in bone mineral of increasing age, and poorly crystalline hydroxyapatite in the most mature mineral portions of the tissue. Growth plate cartilage examination has revealed calcium and phosphorus in single mitochondrial granules within chondrocytes and in certain extracellular particles distinct from matrix vesicles. These results have provided important information about the possible roles of cells, extracellular components, and the organic matrix in the regulation of mineralization and about the composition, structure, and organization of the mineral phase as a function of progressively increasing age and maturation of the tissues studied.
Co-precipitation of dissolved organic matter by calcium carbonate in Pyramid Lake, Nevada
Leenheer, Jerry A.; Reddy, Michael M.
2008-01-01
Our previous research has demonstrated that dissolved organic matter (DOM) influences calcium carbonate mineral formation in surface and ground water. To better understand DOM mediation of carbonate precipitation and DOM co-precipitation and/or incorporation with carbonate minerals, we characterized the content and speciation of DOM in carbonate minerals and in the lake water of Pyramid Lake, Nevada, USA. A 400-gram block of precipitated calcium carbonate from the Pyramid Lake shore was dissolved in 8 liters of 10% acetic acid. Particulate matter not dissolved by acetic acid was removed by centrifugation. DOM from the carbonate rock was fractionated into nine portions using evaporation, dialysis, resin adsorption, and selective precipitations to remove acetic acid and inorganic constituents. The calcium carbonate rock contained 0.23% DOM by weight. This DOM was enriched in polycarboxylic proteinaceous acids and hydroxy-acids in comparison with the present lake water. DOM in lake water was composed of aliphatic, alicyclic polycarboxylic acids. These compound classes were found in previous studies to inhibit calcium carbonate precipitation. DOM fractions from the carbonate rock were 14C-age dated at about 3,100 to 3,500 years before present. The mechanism of DOM co-precipitation and/or physical incorporation in the calcium carbonate is believed to be due to formation of insoluble calcium complexes with polycarboxylic proteinaceous acids and hydroxy-acids that have moderately large stability constants at the alkaline pH of the lake. DOM co-precipitation with calcium carbonate and incorporation in precipitated carbonate minerals removes proteinaceous DOM, but nearly equivalent concentrations of neutral and acidic forms of organic nitrogen in DOM remain in solution. Calcium carbonate precipitation during lime softening pretreatment of drinking water may have practical applications for removal of proteinaceous disinfection by-product precursors.
He, Gen; Gajjeraman, Sivakumar; Schultz, David; Cookson, David; Qin, Chunlin; Butler, William T; Hao, Jianjun; George, Anne
2005-12-13
Bone and dentin biomineralization are well-regulated processes mediated by extracellular matrix proteins. It is widely believed that specific matrix proteins in these tissues modulate nucleation of apatite nanoparticles and their growth into micrometer-sized crystals via molecular recognition at the protein-mineral interface. However, this assumption has been supported only circumstantially, and the exact mechanism remains unknown. Dentin matrix protein 1 (DMP1) is an acidic matrix protein, present in the mineralized matrix of bone and dentin. In this study, we have demonstrated using synchrotron small-angle X-ray scattering that DMP1 in solution can undergo oligomerization and temporarily stabilize the newly formed calcium phosphate nanoparticle precursors by sequestering them and preventing their further aggregation and precipitation. The solution structure represents the first low-resolution structural information for DMP1. Atomic force microscopy and transmission electron microscopy studies further confirmed that the nascent calcium phosphate nuclei formed in solution were assembled into ordered protein-mineral complexes with the aid of oligomerized DMP1, recombinant and native. This study reveals a novel mechanism by which DMP1 might facilitate initiation of mineral nucleation at specific sites during bone and dentin mineralization and prevent spontaneous calcium phosphate precipitation in areas in which mineralization is not desirable.
Paschalis, E P; Gamsjaeger, S; Hassler, N; Fahrleitner-Pammer, A; Dobnig, H; Stepan, J J; Pavo, I; Eriksen, E F; Klaushofer, K
2017-02-01
Prospective, controlled clinical trials in postmenopausal osteoporosis typically compare effects of an active drug with placebo in addition to vitamin D and calcium supplementation in both treatment arms. While clinical benefits are documented, the effect of this supplementation in the placebo arm and in clinical practice on bone material composition properties is unknown. The purpose of the present study was to evaluate these bone quality indices (specifically mineral/matrix, nanoporosity, glycosaminoglycan content, mineral maturity/crystallinity, and pyridinoline content) in patients that either received long-term vitamin D (400-1200IU) and calcium (1.0-1.5g) supplementation, or did not. We have analyzed by Raman microspectroscopy the bone forming trabecular surfaces of iliac crest in pre-treatment samples of a teriparatide study and the endpoint biopsies of the control arm obtained from the HORIZON trial. In general, the mineral/matrix ratio and the glycosaminoglycan (GAG) content was higher while nanoporosity, (a surrogate for tissue water content), the mineral maturity/crystallinity (MMC) and the pyridinoline (Pyd) content was lower in patients without long-term supplementation. Moreover, all indices were significantly dependent on tissue age. In conclusion, vitamin D and calcium supplementation is associated with altered mineral and organic matrix properties. Copyright © 2016 Elsevier Inc. All rights reserved.
Kim, Hyerang; Lee, Saningun; Choue, Ryowon
2011-07-04
High protein diet has been known to cause metabolic acidosis, which is manifested by increased urinary excretion of nitrogen and calcium. Bodybuilders habitually consumed excessive dietary protein over the amounts recommended for them to promote muscle mass accretion. This study investigated the metabolic response to high protein consumption in the elite bodybuilders. Eight elite Korean bodybuilders within the age from 18 to 25, mean age 21.5 ± 2.6. For data collection, anthropometry, blood and urinary analysis, and dietary assessment were conducted. They consumed large amounts of protein (4.3 ± 1.2 g/kg BW/day) and calories (5,621.7 ± 1,354.7 kcal/day), as well as more than the recommended amounts of vitamins and minerals, including potassium and calcium. Serum creatinine (1.3 ± 0.1 mg/dl) and potassium (5.9 ± 0.8 mmol/L), and urinary urea nitrogen (24.7 ± 9.5 mg/dl) and creatinine (2.3 ± 0.7 mg/dl) were observed to be higher than the normal reference ranges. Urinary calcium (0.3 ± 0.1 mg/dl), and phosphorus (1.3 ± 0.4 mg/dl) were on the border of upper limit of the reference range and the urine pH was in normal range. Increased urinary excretion of urea nitrogen and creatinine might be due to the high rates of protein metabolism that follow high protein intake and muscle turnover. The obvious evidence of metabolic acidosis in response to high protein diet in the subjects with high potassium intake and intensive resistance exercise were not shown in this study results. However, this study implied that resistance exercise with adequate mineral supplementation, such as potassium and calcium, could reduce or offset the negative effects of protein-generated metabolic changes. This study provides preliminary information of metabolic response to high protein intake in bodybuilders who engaged in high-intensity resistance exercise. Further studies will be needed to determine the effects of the intensity of exercise and the level of mineral intakes, especially potassium and calcium, which have a role to maintain acid-base homeostasis, on protein metabolism in large population of bodybuilders.
Mineral and nitrogen metabolic studies, experiment M071
NASA Technical Reports Server (NTRS)
Whedon, G. D.; Lutwak, L.; Rambaut, P. C.; Whittle, M. W.; Smith, M. C., Jr.; Reid, J.; Leach, C. S.; Stadler, C. R.; Sanford, D. D.
1977-01-01
The similarity between bed rest test and space flight effects on human mineral and nitrogen metabolisms indicates impairment of capable musculoskeletal functions. A pattern of urinary calcium increases and total calcium shifts suggests that calcium losses continue with time. Significant losses of nitrogen and phosphorus are associated with reduction in muscle tissue. It is concluded that capable musculoskeletal function is likely to be impaired during space flights of 1 1/2 to 3 years duration.
Fisher, Jennifer O; Mitchell, Diane C; Smiciklas-Wright, Helen; Mannino, Michelle L; Birch, Leann L
2008-01-01
Background Longitudinal data regarding the influence of beverage intakes on calcium adequacy are lacking. Objective This study evaluated calcium intake from ages 5 to 9 y as a function of mother-daughter beverage choices and as a predictor of bone mineral status. Design Intakes of energy, calcium, milk, sweetened beverages, fruit juices, and non-energy-containing beverages were measured with the use of three 24-h dietary recalls in 192 non-Hispanic white girls aged 5, 7, and 9 y and their mothers. Calcium intakes from ages 5 to 9 y were categorized as either meeting or falling below recommended adequate intakes (AIs). The girls’ bone mineral status was assessed with dual-energy X-ray absorptiometry at age 9 y. Results The mean 5-y calcium intake was related to bone mineral density at age 9 y (β = 0.27, P < 0.001). The girls who met the AI for calcium were not heavier (P = 0.83) but had higher energy intakes (P < 0.0001) than did the girls who consumed less than the AI. Compared with the girls who consumed less than the AI, the girls who met the AI consumed, on average, almost twice as much milk (P < 0.0001), had smaller decreases in milk intake (P < 0.01), and consumed 18% less sweetened beverages (P < 0.01) from ages 5 to 9 y; the 2 groups did not differ significantly in juice and non-energy-containing beverage intakes. The girls who met the AI were also served milk more frequently than were the girls who consumed less than the AI (P < 0.0001) and had mothers who drank milk more frequently (P < 0.01) than did the mothers of the girls who consumed less than the AI. Conclusions These findings provide new longitudinal evidence that calcium intake predicts bone mineral status during middle childhood and reflects mother-daughter beverage choice patterns that are established well before the rapid growth and bone mineralization observed in adolescence. PMID:15051617
The influence of mineral particles on fibroblast behaviour: A comparative study.
Soto Veliz, Diosangeles; Luoto, Jens C; Pulli, Ilari; Toivakka, Martti
2018-07-01
Minerals are versatile tools utilised to modify and control the physical-chemical and functional properties of substrates. Those properties include ones directing cell fate; thus, minerals can potentially provide a direct and inexpensive method to manipulate cell behaviour. This paper shows how different minerals influence human dermal fibroblast behaviour depending on their properties. Different calcium carbonates, calcium sulphates, silica, silicates, and titanium dioxide were characterised using TEM, ATR-FTIR, and zeta potential measurements. Mineral-cell interactions were analysed through MTT assay, LDH assay, calcein AM staining, live cell imaging, immunofluorescence staining, western blot, and extra/intracellular calcium measurements. Results show that the interaction of the fibroblasts with the minerals was governed by a shared period of adaptation, followed by increased proliferation, growth inhibition, or increased toxicity. Properties such as size, ion release and chemical composition had a direct influence on the cells leading to cell agglomeration, morphological changes, and the possible formation of protein-mineral complexes. In addition, zeta potential and FTIR measurements of the minerals showed adsorption of the cell culture media onto the particles. This article provides fundamental insight into the mineral-fibroblast interactions, and makes it possible to arrange the minerals according to the time-dependent cellular response. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zeman, Antonín; Šmíd, Michal; Havelcová, Martina; Coufalová, Lucie; Kučková, Štěpánka; Velčovská, Martina; Hynek, Radovan
2013-11-01
Degenerative aortic stenosis has become a common and dangerous disease in recent decades. This disease leads to the mineralization of aortic valves, their gradual thickening and loss of functionality. We studied the detailed assessment of the proportion and composition of inorganic and organic components in the ossified aortic valve, using a set of analytical methods applied in science: polarized light microscopy, scanning electron microscopy, X-ray fluorescence, X-ray diffraction, gas chromatography/mass spectrometry and liquid chromatography-tandem mass spectrometry. The sample valves showed the occurrence of phosphorus and calcium in the form of phosphate and calcium carbonate, hydroxyapatite, fluorapatite and hydroxy-fluorapatite, with varying content of inorganic components from 65 to 90 wt%, and with phased development of degenerative disability. The outer layers of the plaque contained an organic component with peptide bonds, fatty acids, proteins and cholesterol. The results show a correlation between the formation of fluorapatite in aortic valves and in other parts of the human bodies, associated with the formation of bones.
Assessment of calcium and zinc accumulation in cultivated and wild apples.
Liao, Liao; Fang, Ting; Ma, Baiquan; Deng, Xianbao; Zhao, Li; Han, Yuepeng
2017-09-01
Apple is one of the staple fruits worldwide which are a good source of mineral nutrients. However, little is known about genetic variation for mineral nutrition in apple germplasm. In this study, the calcium and zinc contents in mature fruits of 378 apple cultivars and 39 wild relatives were assessed. Mineral concentrations were quantified using flame atomic absorption spectroscopy (FAAS). Both calcium and zinc accumulation showed great variation among accessions tested. Overall, wild fruits were significantly richer in zinc than cultivated fruits, while the average concentration of calcium was similar between cultivated and wild fruits. The difference in zinc concentration between wild and cultivated fruits may be an indirect result of artificial selection on fruit characteristics during apple domestication. Moreover, calcium concentration in fruit showed a decreasing trend throughout fruit development of apple, while zinc concentration in fruit displayed a complex variation pattern in the late stages of fruit development. The finding of a wild genetic variation for fruit calcium and zinc accumulation in apple germplasm could be helpful for future research on genetic dissection and improvement of calcium and zinc accumulation in apple fruit. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Moyo, Mack; Amoo, Stephen O.; Aremu, Adeyemi O.; Gruz, Jiri; Šubrtová, Michaela; Jarošová, Monika; Tarkowski, Petr; Doležal, Karel
2018-01-01
The study compared mineral, chemical and antioxidant qualities of Cleome gynandra, a wild leafy vegetable, with two widely consumed commercial vegetables, Brassica oleracea and Beta vulgaris. Mineral nutrients were quantified with inductively coupled plasma mass spectrometry (ICP-MS), phenolic compounds using ultra-high performance liquid chromatography coupled to a mass spectrometer (UHPLC-MS) and β-carotene and vitamin C using high performance liquid chromatography with a photodiode array detector (HPLC-PDA). The antioxidant potential was evaluated using 2,2–diphenyl−1–picryl hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays. Cleome gynandra had highest concentrations of phosphorus, potassium, calcium, iron, zinc, ascorbic acid, total phenolics, and flavonoids; whereas sodium, magnesium, manganese, copper and β-carotene were higher for B. vulgaris. The significantly higher antioxidant activity (P ≤ 0.05) exhibited by C. gynandra in comparison to the two commercial vegetables may be due to its significantly high levels of vitamin C and phenolic acids. These findings on the mineral, chemical and antioxidant properties of C. gynandra provide compelling scientific evidence of its potential in adding diversity to the diet and contributing toward the daily nutritional requirements of millions of people for food and nutritional security. PMID:29354633
Cheng, An; Chao, Sao-Jeng; Lin, Wei-Ting
2013-01-01
Leaching of calcium ions increases the porosity of cement-based materials, consequently resulting in a negative effect on durability since it provides an entry for aggressive harmful ions, causing reinforcing steel corrosion. This study investigates the effects of leaching behavior of calcium ions on the compression and durability of cement-based materials. Since the parameters influencing the leaching behavior of cement-based materials are unclear and diverse, this paper focuses on the influence of added mineral admixtures (fly ash, slag and silica fume) on the leaching behavior of calcium ions regarding compression and durability of cemented-based materials. Ammonium nitrate solution was used to accelerate the leaching process in this study. Scanning electron microscopy, X-ray diffraction analysis, and thermogravimetric analysis were employed to analyze and compare the cement-based material compositions prior to and after calcium ion leaching. The experimental results show that the mineral admixtures reduce calcium hydroxide quantity and refine pore structure through pozzolanic reaction, thus enhancing the compressive strength and durability of cement-based materials. PMID:28809247
Jayalakshmi, S; Platel, Kalpana
2016-05-18
Negative interactions between minerals interfering with each other's absorption are of concern when iron and calcium supplements are given to pregnant women and children. We have previously reported that supplemental levels of iron and calcium inhibit the bioaccessibility of zinc, and compromise zinc status in rats fed diets with high levels of these two minerals. The present study examined the effect of supplemental levels of iron and calcium on the recovery of zinc status during a zinc repletion period in rats rendered zinc-deficient. Iron and calcium, both individually and in combination, significantly interfered with the recovery of zinc status in zinc deficient rats during repletion with normal levels of zinc in the diet. Rats maintained on diets containing supplemental levels of these two minerals had significantly lower body weight, and the concentration of zinc in serum and organs was significantly lower than in zinc-deficient rats not receiving the supplements. Iron and calcium supplementation also significantly inhibited the activity of zinc-containing enzymes in the serum as well as liver. Both iron and calcium independently exerted this negative effect on zinc status, while their combination seemed to have a more prominent effect, especially on the activities of zinc containing enzymes. This investigation is probably the first systematic study on the effect of these two minerals on the zinc status of zinc deficient animals and their recovery during repletion with normal amounts of zinc.
Bargar, Keith E.; Beeson, Melvin H.
1985-01-01
Y-3, a U.S. Geological Survey research diamond-drill hole in Lower Geyser Basin, Yellowstone National Park, Wyoming, reached a depth of 156.7 m. The recovered drill core consists of 42.2 m of surficial (mostly glacial) sediments and two rhyolite flows (Nez Perce Creek flow and an older, unnamed rhyolite flow) of the Central Plateau Member of the Pleistocene Plateau Rhyolite. Hydrothermal alteration is fairly extensive in most of the drill core. The surficial deposits are largely cemented by silica and zeolite minerals; and the two rhyolite flows are, in part, bleached by thermal water that deposited numerous hydrothermal minerals in cavities and fractures. Hydrothermal minerals containing sodium as a dominant cation (analcime, clinoptilolite, mordenite, Na-smectite, and aegirine) are more abundant than calcium-bearing minerals (calcite, fluorite, Ca-smectite, and pectolite) in the sedimentary section of the drill core. In the volcanic section of drill core Y-3, calcium-rich minerals (dachiardite, laumontite, yugawaralite, calcite, fluorite, Ca-smectite, pectolite, and truscottite) are predominant over sodium-bearing minerals (aegirine, mordenite, and Na-smectite). Hydrothermal minerals that contain significant amounts of potassium (alunite and lepidolite in the sediments and illitesmectite in the rhyolite flows) are found in the two drill-core intervals. Drill core y:.3 also contains hydrothermal silica minerals (opal, [3-cristobalite, chalcedony, and quartz), other clay minerals (allophane, halloysite, kaolinite, and chlorite), gypsum, pyrite, and hematite. The dominance of calcium-bearing hydrothermal minerals in the lower rhyolitic section of the y:.3 drill core appears to be due to loss of calcium, along with potassium, during adiabatic cooling of an ascending boiling water.
NASA Astrophysics Data System (ADS)
Kristensen, L.; Cornwell, G.; Sedlacek, A. J., III; Prather, K. A.
2016-12-01
Mineral dust particles can serve as cloud condensation nuclei (CCN), with enhanced CCN activity observed when the dust is mixed with additional soluble species. Long range atmospheric transport can change the composition of dust particles through aging, cloud processing and mixing with other particles. The CalWater2 campaign measured single particles and cloud dynamics to investigate the influence aerosols have on the hydrological cycle in California. An Aircraft Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) was used to characterize and identify single particles within clouds potentially acting as ice and cloud nuclei. Two matching flights over California's mountains in March 2015 detected significantly different particle types that resulted in different precipitation totals. Calcium dust dominated the particle composition during the first flight which had an observed decrease in orographic precipitation. Particle composition and air mass back trajectories indicate an Asian desert origin. The calcium dust particles contained secondary acids, in particular oxalic acid, acquired during transport from Asia to California. This chemical processing likely increased the solubility of the dust, enabling the particles to act as more effective CCN. The chemical composition also showed oligomeric carbonaceous species were mixed with the calcium dust particles, potentially further increasing the solubility the particles. A single particle soot photometer (SP2) measured black carbon concurrently and returned intense incandescence when calcium dust was present, confirming the calcium dust particles were internally mixed with a carbonaceous species. Dust particles were greatly reduced during the second flight with local biomass burning particles the dominant type. Observed precipitation in California were within forecast levels during the second flight. These single particle measurements from CalWater2 show that dust particles from Asia can affect cloud process and thus precipitation in California.
NASA Astrophysics Data System (ADS)
Widyastuti, S.; Pramushinta, I. A.
2018-03-01
Prepared and characterized calcium carbonat calcite nanocrystals improves solubility. Calcium carbonat calcite nanocrystals were synthesized using precipitation method from the waste of blood clam cockle shells (Anadara granosa Linn). This study was conducted to analyze mineral composition of nanocrystals calcium carbonat calcite cockle (Anadara granosa) shell for calcium fortification of food applications and to evaluate the solubilities of Calsium and Phospor. The sample of nanocrystals from cockle shells was evaluated to determine the content of 11 macro-and micro-elements. These elements are Calcium (Ca), Magnesium (Mg), Sodium (Na), Phosphorus (P), Potassium (K), Ferrum (Fe), Copper (Cu), Nickel (Ni), Zink (Zn), Boron (B) and Silica (Si)). Cockleshell powders were found to contain toxic elements below detectable levels. The solubilities of Calcium and Phospor were p<0.05.
Rowe, D J; Ko, S; Tom, X M; Silverstein, S J; Richards, D W
1999-09-01
Vitamin C or ascorbate is important in wound healing due to its essential role in collagen synthesis. To study wound healing in the periodontium, cells adherent to expanded polytetrafluoroethylene (ePTFE) augmentation membranes, recovered from edentulous ridge augmentation procedures, have been established in culture in our laboratories. The objective of this study was to determine whether treatment of these cells with a calcium ascorbate, which contains vitamin C metabolites (metabolite-supplemented ascorbate), would increase the production of collagenous protein and mineralized tissue in vitro, as compared to unsupplemented calcium ascorbate (ascorbate). Cells derived from ePTFE membranes were cultured with beta-glycerophosphate and the test agents for 2 to 5 weeks, and the surface areas of the cell cultures occupied by mineralized nodules were measured using computerized image analysis. One experiment tested the effects of calcium threonate, one of the vitamin C metabolites in metabolite-supplemented ascorbate. Incorporation of radioactive proline and glycine was used as a measure of total protein (radioactivity precipitated by trichloracetic acid) and collagenase-digestible protein (radioactivity released by collagenase digestion.) Co-localization of collagen and fibronectin was examined by immunofluorescence. In vitro treatment of these cells with metabolite-supplemented ascorbate increased the area of the cell cultures occupied by mineralized nodules after 5 weeks. Cell cultures treated with metabolite-supplemented ascorbate also exhibited significant increases in total protein. The increase in collagenous proteins in these cultures accounted for 85% of the increase in total protein. The greatest difference between treatment groups was observed in the cell-associated fraction containing the extracellular matrix. The additional collagen exhibited normal co-distribution with fibronectin. In cultures treated with ascorbate spiked with calcium threonate, the area of mineralized tissue was significantly greater than in ascorbate-treated cultures, but was less than that observed in cultures treated with metabolite-supplemented ascorbate. In vitro treatment with ascorbate containing vitamin C metabolites enhanced the formation of mineralized nodules and collagenous proteins. Calcium threonate may be one of the metabolites influencing the mineralization process. Identifying factors which facilitate the formation of mineralized tissue has significant clinical ramifications in terms of wound healing and bone regeneration.
[Effects of nandrolone decanoate on bone mineral content and intestinal absorption of calcium].
Nuti, R; Righi, G A; Turchetti, V; Vattimo, A
1984-01-28
To evaluate the effects of a long-term treatment with nandrolone decanoate on metabolism of the skeleton, a double-blind randomized study was carried out in women with joint diseases without metabolic bone derangement. Ten patients were treated with 50 mg of nandrolone decanoate every three weeks for two years; in six subjects a treatment with placebo was performed. As it concerns plasma calcium and phosphate, serum alkaline phosphatase, urinary excretion of calcium, phosphate, hydroxyproline and cAMP, as parathyroid index, it was not observed significant differences in the two examined groups. While in placebo group at the end of the study the intestinal radiocalcium remained unchanged and bone mineral content showed a slight decrease, on the contrary nandrolone decanoate treatment promoted a significant improvement in intestinal calcium absorption and an increase in bone mineral content.
FT-Raman spectroscopic study of calcium-rich and magnesium-rich carbonate minerals.
Edwards, Howell G M; Villar, Susana E Jorge; Jehlicka, Jan; Munshi, Tasnim
2005-08-01
Calcium and magnesium carbonates are important minerals found in sedimentary environments. Although sandstones are the most common rock colonized by endolith organisms, the production of calcium and magnesium carbonates is important in survival strategies of organisms and as a source for the removal of oxalate ions. Extremophile organisms in some situations may convert or destroy carbonates of calcium and magnesium, which gives important information about the conditions under which these organisms can survive. The identification on the surface of Mars of 'White Rock' formations, in Juventae Chasma or Sabaea Terra, as possibly carbonate rocks makes the study of these minerals a prerequisite of remote Martian exploration. Here, we show the protocol for the identification by Raman spectroscopy of different calcium and magnesium carbonates and we present a database of relevance in the search for life, extinct or extant, on Mars; this will be useful for the assessment of data obtained from remote, miniaturized Raman spectrometers now proposed for Mars exploration.
Mineralized alginate hydrogels using marine carbonates for bone tissue engineering applications.
Diaz-Rodriguez, P; Garcia-Triñanes, P; Echezarreta López, M M; Santoveña, A; Landin, M
2018-09-01
The search for an ideal bone tissue replacement has led to the development of new composite materials designed to simulate the complex inorganic/organic structure of bone. The present work is focused on the development of mineralized calcium alginate hydrogels by the addition of marine derived calcium carbonate biomineral particles. Following a novel approach, we were able to obtain calcium carbonate particles of high purity and complex micro and nanostructure dependent on the source material. Three different types of alginates were selected to develop inorganic/organic scaffolds in order to correlate alginate composition with scaffold properties and cell behavior. The incorporation of calcium carbonates into alginate networks was able to promote extracellular matrix mineralization and osteoblastic differentiation of mesenchymal stem cells when added at 7 mg/ml. We demonstrated that the selection of the alginate type and calcium carbonate origin is crucial to obtain adequate systems for bone tissue engineering as they modulate the mechanical properties and cell differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.
[The functions of calcium-sensing receptor in regulating mineral metabolism.
Kinoshita, Yuka
Calcium-sensing receptor(CaSR)which belongs to a G protein-coupled receptor family is one of the key elements in regulating calcium homeostasis. CaSR has been identified as a receptor to control parathyroid hormone(PTH)secretion in parathyroid glands according to serum calcium ion(Ca2+)levels. It has also been shown that CaSR controls reabsorption of water and several cations including Ca2+and magnesium ion(Mg2+)in renal tubular cells. This review summarizes the functions and roles of CaSR in mineral metabolism that are exerted in parathyroid glands, kidney, and intestine.
Bartges, Joseph W; Kirk, Claudia A; Cox, Sherry K; Moyers, Tamberlyn D
2013-10-01
To evaluate the influence of acidifying or alkalinizing diets on bone mineral density and urine relative supersaturation (URSS) with calcium oxalate and struvite in healthy cats. 6 castrated male and 6 spayed female cats. 3 groups of 4 cats each were fed diets for 12 months that differed only in acidifying or alkalinizing properties (alkalinizing, neutral, and acidifying). Body composition was estimated by use of dual energy x-ray absorptiometry, and 48-hour urine samples were collected for URSS determination. Urine pH differed significantly among diet groups, with the lowest urine pH values in the acidifying diet group and the highest values in the alkalinizing diet group. Differences were not observed in other variables except urinary ammonia excretion, which was significantly higher in the neutral diet group. Calcium oxalate URSS was highest in the acidifying diet group and lowest in the alkalinizing diet group; struvite URSS was not different among groups. Diet was not significantly associated with bone mineral content or density. Urinary undersaturation with calcium oxalate was achieved by inducing alkaluria. Feeding an alkalinizing diet was not associated with URSS with struvite. Bone mineral density and calcium content were not adversely affected by diet; therefore, release of calcium from bone caused by feeding an acidifying diet may not occur in healthy cats.
NASA Technical Reports Server (NTRS)
Tou, Janet; Arnaud, Sara B.; Grindeland, Richard; Wade, Charles
2004-01-01
Spaceflight simulation studies use chow diets while spaceflight studies use a semi-purified &et. To determine whether the differences in these diets would affect the changes in unweighted bone, we compared the effects of purified vs chow diet on bone parameters, urinary calcium, plasma estradiol, and urinary corticosterone (CORT) in sexually mature female Sprague-Dawley rats. Rats fed purified AIN-93G or chow diet were kept ambulatory (AMB) or subjected to a spaceflight simulation model of unweighted hindlimbs (HLS) for 38 days. Body mass of treatment groups was similar although food intake and caloric density of the diets differed. Both HLS diet groups showed similar decreases in bone mineral content and mechanical strength in unweighted femurs compared to AMB (p<0.05). However, femur length was lower (p<0.05) in the chow-fed than AIN-93G fed groups. Urinary calcium excretion was greater in chow than AIN-93G fed rats, consistent with the higher level of calcium in the diet. Plasma estradiol was lower in HLS than in AMB fed AIN-93G, but similar in HLS and AMB chow fed groups. Femur mineral content was related to plasma estradiol (r(sup 2) =0.91, p<0.00l). Urinary CORT excretion was increased during initial HLS and elevated in HLS/chow-fed rats. Diets did not appear to affect the osteopenia induced by unweighting, but effects on bone growth, calcium excretion, plasma estradiol and urinary CORT do not support the view that these diets can by used interchangeably in bone studies.
Effects of simulated weightlessness on bone mineral metabolism
NASA Technical Reports Server (NTRS)
Globus, R. K.; Bikle, D. D.; Morey-Holton, E.
1984-01-01
It is pointed out that prolonged space flight, bedrest, and immobilization are three factors which can produce a negative calcium balance, osteopenia, and an inhibition of bone formation. It is not known whether the effects of gravity on bone mineral metabolism are mediated by systemic endocrine factors which affect all bones simultaneously, or by local factors which affect each bone individually. The present investigation has the objective to test the relative importance of local vs. systemic factors in regulating the bone mineral response to conditions simulating weightlessness. Experiments were conducted with male Sprague-Dawley rats. The test conditions made it possible to compare the data from weighted and unweighted bones in the same animal. The obtained findings indicate that a decrease in bone mass relative to control value occurs rapidly under conditions which simulate certain aspects of weightlessness. However, this decrease reaches a plateau after 10 days.
Millet, Melanie; Poupard, Pascal; Le Quéré, Jean-Michel; Bauduin, Remi; Guyot, Sylvain
2017-08-09
Producers of apple-based beverages are confronted with colloidal instability. Haze is caused by interactions between molecules that lead to the formation of aggregates. Haze composition in three apple-based beverages, namely, French sparkling cider, apple juice, and pommeau, was studied. Phenolic compounds, proteins, polysaccharides, and minerals were analyzed using global and detailed analytical methods. The results explained <75% (w/w) of haze dry mass. Polyphenols, represented mainly by procyanidins, were the main compounds identified and accounted for 10-31% of haze. However, oxidized phenolic compounds were probably underestimated and may represent a high proportion of haze. Proteins were present in all of the samples in proportions of <6% of haze except in two apple juice hazes, where they were the main constituents (18 and 24%). Polysaccharides accounted for 0-30% of haze. Potassium and calcium were the main minerals.
Hirai, Takao; Kobayashi, Tatsuya; Nishimori, Shigeki; Karaplis, Andrew C.; Goltzman, David
2015-01-01
The blood calcium concentration during fetal life is tightly regulated within a narrow range by highly interactive homeostatic mechanisms that include transport of calcium across the placenta and fluxes in and out of bone; the mechanisms of this regulation are poorly understood. Our findings that endochondral bone-specific PTH/PTHrP receptor (PPR) knockout (KO) mice showed significant reduction of fetal blood calcium concentration compared with that of control littermates at embryonic day 18.5 led us to focus on bone as a possibly major determinant of fetal calcium homeostasis. We found that the fetal calcium concentration of Runx2 KO mice was significantly higher than that of control littermates, suggesting that calcium flux into bone had a considerable influence on the circulating calcium concentration. Moreover, Runx2:PTH double mutant fetuses showed calcium levels similar to those of Runx2 KO mice, suggesting that part of the fetal hypocalcemia in PTH KO mice was caused by the increment of the mineralized bone mass allowed by the formation of osteoblasts. Finally, Rank:PTH double mutant mice had a blood calcium concentration even lower than that of the either Rank KO or PTH KO mice alone at embryonic day 18.5. These observations in our genetic models suggest that PTH/PTHrP receptor signaling in bones has a significant role of the regulation of fetal blood calcium concentration and that both placental transport and osteoclast activation contribute to PTH's hypercalcemic action. They also show that PTH-independent deposition of calcium in bone is the major controller of fetal blood calcium level. PMID:26052897
Zhao, Ai; Xue, Yong; Zhang, Yumei; Li, Wenjun; Yu, Kai; Wang, Peiyu
2016-01-01
Objective Objectives of this study were 1) to investigate the mineral intake by Chinese lactating women, 2) to explore the dietary source of minerals, and 3) the ratios between different dietary minerals. Methods A total of 468 lactating women in 5–240 days post-partum participated in this study. Food intakes by participants were measured using one time of 24-hour dietary recall, and minerals from food were calculated based on the Chinese Food Composition Table, second edition. Results In post-partum, women had inadequate food intake. 81.0% of women’s daily intake of dairy products was lower than 300g, and 97.1% of women’s daily intake of salt over 6g. For mineral intake, there were 81.8%, 59.0%, 47.6%, 45.7% and 66.8% of women’s calcium, magnesium, iron, zinc and selenium intake lower than the estimated average requirement, respectively, and 91.7% of women’s excessive intake of sodium. The calcium/phosphorus and sodium/potassium ratios were 0.41±0.26/1 and 3.13±2.89/1, respectively. Considering the dietary sources of minerals, 27.3%, 25.3% and 30.1% of iron, zinc and calcium were from animal-based food, respectively, and 60.3%, 66.1% and 58.0% of iron, zinc and calcium were from plant-based food, respectively. The phosphorus-protein ratio was 0.014±0.003/1. Lactation stage was associated with nutrient intake. Women within 30 days post-partum and the ones who live in Guangzhou had a significantly lower intake of certain minerals, while women with a high education experience had a high intake of calcium, potassium, iron and zinc. Productive age, whether obese or not, and delivery ways were not associated with mineral intakes (P all >0.05). Conclusion Chinese women in three studied cities had an inappropriate food intake and resulted in both insufficient and excessive intakes of certain minerals. PMID:26730592
Floreani, A; Carderi, I; Ferrara, F; Rizzotto, E R; Luisetto, G; Camozzi, V; Baldo, V
2007-06-01
International guidelines for managing osteoporosis in cirrhosis or severe cholestasis indicate a <-2.5 t-score as a cut-off for medical treatment, while no treatment is recommended in the case of osteopenia (t-scores ranging from -1.0 to -2.5). We conducted a prospective study in primary biliary cirrhosis with a view to optimizing the rationale for the medical treatment of bone loss. All naïve post-menopausal women with primary biliary cirrhosis were enrolled in the study. Bone metabolism was evaluated by measuring 25-hydroxy-vitamin D, parathyroid hormone, osteocalcin. Bone mineral density was assessed at the lumbar spine by dual-photon X-ray absorptiometry at the baseline and every 2 years for up to 4 years. Patients with either osteopenia or osteoporosis received the following treatment: oral calcium carbonate (1000 mg/day)+vitamin D3 (880 IU/day)+i.m. disodium clodronate 100mg every 10 days for 4 years. Ninety-six patients completed the study: 30 had a normal bone mineral density (group 1), 37 had osteopenia (group 2), 29 had osteoporosis (group 3). No significant differences in biochemical parameters of bone metabolism were observed between the three groups. A total of 288 bone mineral density measurements were taken. Linear regression analysis failed to reveal significant changes in t-score over the follow-up in all groups. A 4-year treatment with clodronate+calcium/vitamin D3 supplements does not significantly improve osteoporosis or osteopenia in primary biliary cirrhosis women in menopause, but prevents the natural bone loss in these patients. Extensive international trials are warranted to optimize the prevention and treatment of bone loss in primary biliary cirrhosis.
Goffredo, Stefano; Vergni, Patrizia; Reggi, Michela; Caroselli, Erik; Sparla, Francesca; Levy, Oren; Dubinsky, Zvy; Falini, Giuseppe
2011-01-01
Scleractinian coral skeletons are made mainly of calcium carbonate in the form of aragonite. The mineral deposition occurs in a biological confined environment, but it is still a theme of discussion to what extent the calcification occurs under biological or environmental control. Hence, the shape, size and organization of skeletal crystals from the cellular level through the colony architecture, were attributed to factors as diverse as mineral supersaturation levels and organic mediation of crystal growth. The skeleton contains an intra-skeletal organic matrix (OM) of which only the water soluble component was chemically and physically characterized. In this work that OM from the skeleton of the Balanophyllia europaea, a solitary scleractinian coral endemic to the Mediterranean Sea, is studied in vitro with the aim of understanding its role in the mineralization of calcium carbonate. Mineralization of calcium carbonate was conducted by overgrowth experiments on coral skeleton and in calcium chloride solutions containing different ratios of water soluble and/or insoluble OM and of magnesium ions. The precipitates were characterized by diffractometric, spectroscopic and microscopic techniques. The results showed that both soluble and insoluble OM components influence calcium carbonate precipitation and that the effect is enhanced by their co-presence. The role of magnesium ions is also affected by the presence of the OM components. Thus, in vitro, OM influences calcium carbonate crystal morphology, aggregation and polymorphism as a function of its composition and of the content of magnesium ions in the precipitation media. This research, although does not resolve the controversy between environmental or biological control on the deposition of calcium carbonate in corals, sheds a light on the role of OM, which appears mediated by the presence of magnesium ions. PMID:21799830
Carroccio, Antonio; Soresi, Maurizio; D'Alcamo, Alberto; Sciumè, Carmelo; Iacono, Giuseppe; Geraci, Girolamo; Brusca, Ignazio; Seidita, Aurelio; Adragna, Floriana; Carta, Miriam; Mansueto, Pasquale
2014-11-28
Non-celiac gluten sensitivity (NCGS) or 'wheat sensitivity' (NCWS) is included in the spectrum of gluten-related disorders. No data are available on the prevalence of low bone mass density (BMD) in NCWS. Our study aims to evaluate the prevalence of low BMD in NCWS patients and search for correlations with other clinical characteristics. This prospective observation study included 75 NCWS patients (63 women; median age 36 years) with irritable bowel syndrome (IBS)-like symptoms, 65 IBS and 50 celiac controls. Patients were recruited at two Internal Medicine Departments. Elimination diet and double-blind placebo controlled (DBPC) wheat challenge proved the NCWS diagnosis. All subjects underwent BMD assessment by Dual Energy X-Ray Absorptiometry (DXA), duodenal histology, HLA DQ typing, body mass index (BMI) evaluation and assessment for daily calcium intake. DBPC cow's milk proteins challenge showed that 30 of the 75 NCWS patients suffered from multiple food sensitivity. Osteopenia and osteoporosis frequency increased from IBS to NCWS and to celiac disease (CD) (P <0.0001). Thirty-five NCWS patients (46.6%) showed osteopenia or osteoporosis. Low BMD was related to low BMI and multiple food sensitivity. Values of daily dietary calcium intake in NCWS patients were significantly lower than in IBS controls. An elevated frequency of bone mass loss in NCWS patients was found; this was related to low BMI and was more frequent in patients with NCWS associated with other food sensitivity. A low daily intake of dietary calcium was observed in patients with NCWS.
Sun, Zhongqing; Yue, Bing; Yang, Zhenyu; Li, Xiaowei; Wu, Yongning; Yin, Shian
2013-05-01
To determine the levels of 24 minerals in human milk by inductively coupled plasma mass spectrometry with microwave digestion. The samples were digested by microwave. The contents of minerals were determined by inductively coupled plasma mass spectrometry. The standard reference minerals of 1849a and 1568a from National Institute of Science and Technology were used for quality control. The accuracy and reproduability for this method were evaluated with mix standards and 1849a and 1568a standard reference materials. The ranges of the levels of sodium, magnesium, phosphorus, potassium, calcium, aluminum, chromium, arsenic, selenium, iron, zinc, manganese, copper, molybdenum, vanadium, cobalt, nickel, gallium, cadmium, silver, strontium, cesium, barium, lead in human milk was 34.97-415.83 mg/kg, 19.00-39.52 mg/kg, 102.13-274.53 mg/kg, 351.19-713.99 mg/kg, 180.08-349.64 mg/kg, 0.06-0.44 mg/kg, 0.9-7.37 microg/kg, 0.92-2.72 microg/kg, 0.20-21.15 microg/kg, 0.10-0.70 mg/kg, 0.56-3.25 mg/kg, 3.00-16.12 micro.g/kg, 62.16-591.69 microg/kg, 0.02-6.91 microg/kg, 5.99-13.70 microg/kg, 0.07-2.11 microg/kg, 0.77-209.26 microg/kg, 0.005-0.28 microg/kg, 0.02-0.23 microg/kg, 0.02-0.71 microg/kg, 36.89-132.26 microg/kg, 0.01-4.72 microg/kg, 0.83-28.16 microg/kg, 2.5-5.3 microg/kg, respectively. The levels of minerals in human milk in present study were consisted with other similar studies. The experiment examined the levels of minerals in human milk satisfactorily. The method has high accuracy and good reproducibility, which could be used for understanding the levels of minerals in human milk.
2006-07-01
pipes in hooded channels, and the steel insulated pipes are insulated with mineral wool . In the thermo- concrete laying system the insulation...depends on the type foam insulation used. • Class “A” steel carrier pipe with a mineral wool , foam glass, fiber glass, or calcium silicate insulation...with a mineral wool , foam glass, fiber glass, or calcium silicate insulation covered by a steel con- duit, which has a polyurethane foam insulation
Mineral scale management. Part 1, Case studies
Peter W. Hart; Alan W. Rudie
2006-01-01
Mineral scale increases operating costs, extends downtime, and increases maintenance requirements. This paper presents several successful case studies detailing how mills have eliminated scale. Cases presented include calcium carbonate scale in a white liquor strainer, calcium oxalate scale in the D0 stage of the bleach plant, enzymatic treatment of brown stock to...
USDA-ARS?s Scientific Manuscript database
Objective – To evaluate the mineral content including calcium, phosphorus, zinc, iron, copper, manganese, and selenium of canine commercial pet foods and compare them to current AAFCO recommendations for adult maintenance. Design - Descriptive study. Sample – Forty-five over the counter dry canine p...
Joshi, Alka; Kar, A; Rudra, S G; Sagar, V R; Varghese, E; Lad, M; Khan, I; Singh, B
2016-12-01
Potato chips can be considered as an ideal carrier for targeted nutrient/s delivery as mostly consumed by the vulnerable group (children and teen agers). The present study was planned to fortifiy potato chips with calcium (Calcium lactate) and zinc (Zinc sulphate) using vacuum impregnation technique. At about 70-80 mm Hg vacuum pressure, maximum level of impregnation of both the minerals was achieved. Results showed that after optimization, calcium lactate at 4.81%, zinc sulphate at 0.72%, and vacuum of 33.53 mm Hg with restoration period of 19.52 min can fortify potato chips that can fulfil 10 and 21% need of calcium and zinc, respectively of targeted group (age 4-17 years). The present research work has shown that through this technique, fortification can be done in potato chips which are generally considered as a poor source of minerals. Further to make potato chips more fit to health conscious consumers, rather frying microwaving was done to develop mineral fortified low fat potato chips.
Spatial mapping of mineralization with manganese-enhanced magnetic resonance imaging
Chesnick, I.E.; Centeno, J.A.; Todorov, T.I.; Koenig, A.E.; Potter, K.
2011-01-01
Paramagnetic manganese can be employed as a calcium surrogate to sensitize the magnetic resonance imaging (MRI) technique to the processing of calcium during the bone formation process. At low doses, after just 48h of exposure, osteoblasts take up sufficient quantities of manganese to cause marked reductions in the water proton T1 values compared with untreated cells. After just 24h of exposure, 25??M MnCl2 had no significant effect on cell viability. However, for mineralization studies 100??M MnCl2 was used to avoid issues of manganese depletion in calvarial organ cultures and a post-treatment delay of 48h was implemented to ensure that manganese ions taken up by osteoblasts is deposited as mineral. All specimens were identified by their days in vitro (DIV). Using inductively coupled plasma optical emission spectroscopy (ICP-OES), we confirmed that Mn-treated calvariae continued to deposit mineral in culture and that the mineral composition was similar to that of age-matched controls. Notably there was a significant decrease in the manganese content of DIV18 compared with DIV11 specimens, possibly relating to less manganese sequestration as a result of mineral maturation. More importantly, quantitative T1 maps of Mn-treated calvariae showed localized reductions in T1 values over the calvarial surface, indicative of local variations in the surface manganese content. This result was verified with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We also found that ??R1 values, calculated by subtracting the relaxation rate of Mn-treated specimens from the relaxation rate of age-matched controls, were proportional to the surface manganese content and thus mineralizing activity. From this analysis, we established that mineralization of DIV4 and DIV11 specimens occurred in all tissue zones, but was reduced for DIV18 specimens because of mineral maturation with less manganese sequestration. In DIV25 specimens, active mineralization was observed for the expanding superficial surface and ??R1 values were increased due to the mineralization of small, previously unmineralized areas. Our findings support the use of manganese-enhanced MRI (MEMRI) to study well-orchestrated mineralizing events that occur during embryonic development. In conclusion, MEMRI is more sensitive to the study of mineralization than traditional imaging approaches. ?? 2011.
Spatial mapping of mineralization with manganese-enhanced magnetic resonance imaging☆☆☆
Chesnick, Ingrid E.; Centeno, Jose A.; Todorov, Todor I.; Koenig, Alan E.; Potter, Kimberlee
2011-01-01
Paramagnetic manganese can be employed as a calcium surrogate to sensitize the magnetic resonance imaging (MRI) technique to the processing of calcium during the bone formation process. At low doses, after just 48 h of exposure, osteoblasts take up sufficient quantities of manganese to cause marked reductions in the water proton T1 values compared with untreated cells. After just 24 h of exposure, 25 μM MnCl2 had no significant effect on cell viability. However, for mineralization studies 100 μM MnCl2 was used to avoid issues of manganese depletion in calvarial organ cultures and a post-treatment delay of 48 h was implemented to ensure that manganese ions taken up by osteoblasts is deposited as mineral. All specimens were identified by their days in vitro (DIV). Using inductively coupled plasma optical emission spectroscopy (ICP-OES), we confirmed that Mn-treated calvariae continued to deposit mineral in culture and that the mineral composition was similar to that of age-matched controls. Notably there was a significant decrease in the manganese content of DIV18 compared with DIV11 specimens, possibly relating to less manganese sequestration as a result of mineral maturation. More importantly, quantitative T1 maps of Mn-treated calvariae showed localized reductions in T1 values over the calvarial surface, indicative of local variations in the surface manganese content. This result was verified with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We also found that ΔR1 values, calculated by subtracting the relaxation rate of Mn-treated specimens from the relaxation rate of age-matched controls, were proportional to the surface manganese content and thus mineralizing activity. From this analysis, we established that mineralization of DIV4 and DIV11 specimens occurred in all tissue zones, but was reduced for DIV18 specimens because of mineral maturation with less manganese sequestration. In DIV25 specimens, active mineralization was observed for the expanding superficial surface and ΔR1 values were increased due to the mineralization of small, previously unmineralized areas. Our findings support the use of manganese-enhanced MRI (MEMRI) to study well-orchestrated mineralizing events that occur during embryonic development. In conclusion, MEMRI is more sensitive to the study of mineralization than traditional imaging approaches. PMID:21352960
Vibrational spectroscopic study of poldervaartite CaCa[SiO3(OH)(OH)].
Frost, Ray L; López, Andrés; Scholz, Ricardo; Lima, Rosa Malena Fernandes
2015-02-25
We have studied the mineral poldervaartite CaCa[SiO3(OH)(OH)] which forms a series with its manganese analogue olmiite CaMn[SiO3(OH)](OH) using a range of techniques including scanning electron microscopy, thermogravimetric analysis, Raman and infrared spectroscopy. Chemical analysis shows the mineral is reasonably pure and contains only calcium and manganese with low amounts of Al and F. Thermogravimetric analysis proves the mineral decomposes at 485°C with a mass loss of 7.6% compared with the theoretical mass loss of 7.7%. A strong Raman band at 852 cm(-1) is assigned to the SiO stretching vibration of the SiO3(OH) units. Two Raman bands at 914 and 953 cm(-1) are attributed to the antisymmetric vibrations. Intense prominent peaks observed at 3487, 3502, 3509, 3521 and 3547 cm(-1) are assigned to the OH stretching vibration of the SiO3(OH) units. The observation of multiple OH bands supports the concept of the non-equivalence of the OH units. Vibrational spectroscopy enables a detailed assessment of the molecular structure of poldervaartite. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Lau, A.; Ramirez, J.; Melson, E.; Moran, M.; Baer, L.; Arnaud, S.; Wade, C.; Girten, B.; Dalton, Bonnie (Technical Monitor)
2001-01-01
The effects of 14 days of increased gravitational load, and the absence of adrenal stress hormones on total body bone mineral content (BMC) were examined in male Sprague-Dawley rats. Centrifugation at 2 Gs (2G) was used to increase the gravitational load, and bilateral adrenalectomy (ADX) was used to eliminate the production of adrenal stress hormones. Stationary groups at 1 G (1G) and sham operated (SHAM) animals served as controls. Thirty rats (n=6 or 8) made up the four experimental groups (1G SHAM, 1G ADX, 2G SHAM and 2G ADX). BMC was assessed by dual energy x-ray absorptiometry (DXA) which was performed to determine the total body bone mineral content, and also through bone ashing of the left femur and the left humerus. Activity was determined through biotelemetry, also body mass and food intake were measured. Multi-factorial analysis of variance (MANCOVA) and Newman Keuls post hoc tests were used to analyze significant effects (p is less than 0.05) for the primary variables. Results from both DXA and the ashed femur indicated that BMC decreased significantly with increased G for both the SHAM and ADX groups. The BMC determined by DXA for the 1G ADX group was also significantly lower than the 1G SHAM group, however the 2G SHAM and 2G ADX groups were not significantly different. However, the bone ashing results showed the femur differed significantly only between the rates of centrifugation and not between the ADX and SHAM. The humerus showed no significant difference between any of the groups. There was a significant decrease in body mass with increased G and there was no ADX effect on body mass. When DXA BMC was normalized for body mass changes, there were no significant group differences. However, with bone ashing, the femur BMC/BW still showed significant difference between rates of centrifugation, with the 2G group being lower. Activity level decreased with body mass, and food intake data showed there was significant hypophagia during the first few days of centrifugation. Urine calcium was measured and was found decrease at the start of centrifugation for the 2G groups and rise to a level higher than that of the stationary groups. Finally, the correlation between BW and BMC was determined to be highly correlated (r = .71). These results suggest that the decrease in total body BMC seen with hypergravity may be based to a large extent on the differences in body mass induced by the 2G load.
Going, Scott; Lohman, Timothy; Houtkooper, Linda; Metcalfe, Lauve; Flint-Wagner, Hilary; Blew, Robert; Stanford, Vanessa; Cussler, Ellen; Martin, Jane; Teixeira, Pedro; Harris, Margaret; Milliken, Laura; Figueroa-Galvez, Arturo; Weber, Judith
2003-08-01
Osteoporosis is a major public health concern. The combination of exercise, hormone replacement therapy, and calcium supplementation may have added benefits for improving bone mineral density compared to a single intervention. To test this notion, 320 healthy, non-smoking postmenopausal women, who did or did not use hormone replacement therapy (HRT), were randomized within groups to exercise or no exercise and followed for 12 months. All women received 800 mg calcium citrate supplements daily. Women who exercised performed supervised aerobic, weight-bearing and weight-lifting exercise, three times per week in community-based exercise facilities. Regional bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry. Women who used HRT, calcium, and exercised increased femoral neck, trochanteric and lumbar spine bone mineral density by approximately 1-2%. Trochanteric BMD was also significantly increased by approximately 1.0% in women who exercised and used calcium without HRT compared to a negligible change in women who used HRT and did not exercise. The results demonstrate that regional BMD can be improved with aerobic, weight-bearing activity combined with weight lifting at clinically relevant sites in postmenopausal women. The response was significant at more sites in women who used HRT, suggesting a greater benefit with hormone replacement and exercise compared to HRT alone.
Intake and hedonics of calcium and sodium during pregnancy and lactation in the rat.
Leshem, M; Levin, T; Schulkin, J
2002-03-01
These experiments sought to distinguish whether increased calcium intake during pregnancy and lactation in the rat is due to arousal of a specific calcium appetite, with altered taste hedonics, as occurs with sodium depletion, to reduced taste sensitivity, or to the hyperdipsia of reproduction. We find that, during pregnancy and lactation, CaCl(2) intake is not increased more (in fact less) than intakes of control tastants, MgCl(2) and quinine HCl, and multiparous dams do not have a greater calcium intake than primaparous dams. Changes in taste reactivity to CaCl(2) and to NaCl do not correlate with changes in intake of these minerals during pregnancy or lactation, suggesting that alterations in hedonics or sensitivity do not explain the increased intake of these minerals. Taken together with the increased intake of all the tastants, it may be that the increased intakes of calcium and sodium during reproduction are not due to respective specific appetites or to a general mineral appetite but rather to the reproduction-increased ingestion that may meet all the dam's increased mineral and nutrient requirements. Differences in the degree of increased intakes of tastes may be due to specific alterations in their transduction during reproduction.
Kato, K; Nakagaki, H; Arai, K; Pearce, E I F
2002-01-01
This study was carried out to examine interindividual differences in salivary variables related to plaque accumulation and to estimate their influence on the fluoride retention in plaque in vivo by a mineral-enriching solution. Two saliva samples were taken from 10 subjects, once after brushing and once after 24 h without brushing. Calcium, phosphate and monofluorophosphatase (MFPase) activity in the saliva samples were determined. The salivary flow rate and the debris index were also recorded. After plaque had formed over 3 days within in situ plaque-generating devices, subjects were instructed to rinse with a mineral-enriching mouthrinse three times a day on 4 consecutive days. Plaque exposed to distilled water plus flavoring agents served as a control. Fluoride-free dentifrice was used during the experimental period. Twenty-four hours after the last rinsing, the samples were removed from the mouth, and fluoride and mineral distributions in plaque analyzed using a method previously reported by the authors. Salivary flow, MFPase activity and calcium concentration in saliva were significantly higher after 24 h of plaque accumulation. Rinsing with the mineral-enriching solution produced retention of fluoride and phosphate in the outer and middle layers of plaque. Salivary calcium concentration had a direct effect on fluoride uptake in plaque, but no obvious relationship was found between other salivary variables and the plaque fluoride retention. The salivary calcium effect may be due to enhanced bacterial cell wall binding of fluoride via calcium bridging. Copyright 2002 S. Karger AG, Basel
Fan, Wei; Li, Yanyun; Sun, Qing; Ma, Tengjiao; Fan, Bing
2016-10-21
In infected periapical tissues, Enterococcus faecalis is one of the most common dominant bacteria. Chlorhexidine has been proved to show strong antibacterial ability against E. faecalis but is ineffective in promoting mineralization for tissues around root apex. Mesoporous calcium-silicate nanoparticles are newly synthesized biomaterials with excellent ability to promote mineralization and carry-release bioactive molecules in a controlled manner. In this study, mesoporous calcium-silicate nanoparticles were functionalized with chlorhexidine and their releasing profile, antibacterial ability, effect on cell proliferation and in vitro mineralization property were evaluated. The chlorhexidine was successfully incorporated into mesoporous calcium-silicate nanoparticles by a mixing-coupling method. The new material could release chlorhexidine as well as Ca 2+ and SiO 3 2- in a sustained manner with an alkaline pH value under different conditions. The antimicrobial ability against planktonic E. faecalis was dramatically improved after chlorhexidine incorporation. The nanoparticles with chlorhexidine showed no negative effect on cell proliferation with low concentrations. On dentin slices, the new synthesized material demonstrated a similar inhibitory effect on E. faecalis as the chlorhexidine. After being immersed in SBF for 9 days, numerous apatite crystals could be observed on surfaces of the material tablets. Mesoporous calcium-silicate nanoparticles loaded with chlorhexidine exhibited release of ions and chlorhexidine, low cytotoxicity, excellent antibacterial ability and in vitro mineralization. This material could be developed into a new effective intra-canal medication in dentistry or a new bone defect filling material for infected bone defects.
Margolis, Henry C.; Kwak, Seo-Young; Yamazaki, Hajime
2014-01-01
Vertebrate mineralized tissues, i.e., enamel, dentin, cementum, and bone, have unique hierarchical structures and chemical compositions. Although these tissues are similarly comprised of a crystalline calcium apatite mineral phase and a protein component, they differ with respect to crystal size and shape, level and distribution of trace mineral ions, the nature of the proteins present, and their relative proportions of mineral and protein components. Despite apparent differences, mineralized tissues are similarly derived by highly concerted extracellular processes involving matrix proteins, proteases, and mineral ion fluxes that collectively regulate the nucleation, growth and organization of forming mineral crystals. Nature, however, provides multiple ways to control the onset, rate, location, and organization of mineral deposits in developing mineralized tissues. Although our knowledge is quite limited in some of these areas, recent evidence suggests that hard tissue formation is, in part, controlled through the regulation of specific molecules that inhibit the mineralization process. This paper addresses the role of mineralization inhibitors in the regulation of biological mineralization with emphasis on the relevance of current findings to the process of amelogenesis. Mineralization inhibitors can also serve to maintain driving forces for calcium phosphate precipitation and prevent unwanted mineralization. Recent evidence shows that native phosphorylated amelogenins have the capacity to prevent mineralization through the stabilization of an amorphous calcium phosphate precursor phase, as observed in vitro and in developing teeth. Based on present findings, the authors propose that the transformation of initially formed amorphous mineral deposits to enamel crystals is an active process associated with the enzymatic processing of amelogenins. Such processing may serve to control both initial enamel crystal formation and subsequent maturation. PMID:25309443
Gómez-Cabello, Alba; González-Agüero, Alejandro; Morales, Silvia; Ara, Ignacio; Casajús, José A; Vicente-Rodríguez, Germán
2014-03-01
We aimed to clarify whether a short-term whole body vibration training has a beneficial effect on bone mass and structure in elderly men and women. Randomised controlled trial. A total of 49 non-institutionalised elderly (20 men and 29 women) volunteered to participate in the study. Participants who met the inclusion criteria were randomly assigned to one of the study groups (whole body vibration or control). A total of 24 elderly trained squat positioned on a vibration platform 3 times per week for 11 weeks. Bone-related variables were assessed by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Two-way repeated measures one-way analysis of variance (group by time) was used to determine the effects of the intervention on the bone-related variables and also to determinate the changes within group throughout the intervention period. Analysis of covariance was used to test the differences between groups for bone-related variables in pre- and post-training assessments and in the percentage of change between groups. All analysis were carried out including age, height, subtotal lean mass and daily calcium intake as covariates. 11 weeks of whole body vibration training led to no changes in none of the bone mineral content and bone mineral density parameters measured by dual-energy X-ray absorptiometry through the skeleton. At the tibia, total, trabecular and cortical volumetric bone mineral density decreased significantly in the whole body vibration group (all P<0.05). A short-term whole body vibration therapy is not enough to cause any changes on bone mineral content or bone mineral density and it only produces a slight variation on bone structure among elderly people. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
The role of lean body mass and physical activity in bone health in children.
Baptista, Fátima; Barrigas, Carlos; Vieira, Filomena; Santa-Clara, Helena; Homens, Pedro Mil; Fragoso, Isabel; Teixeira, Pedro J; Sardinha, Luís B
2012-01-01
In the context of physical education curricula, markers of physical fitness (e.g., aerobic capacity, muscular strength, flexibility, and body mass index or body fat) are usually evaluated in reference to health standards. Despite their possible mediating role in the relationship between weight-bearing or muscle forces and features of bone tissue, these attributes of fitness may not be the most relevant to predict skeletal health. It is therefore important to analyze the relative contribution of these factors to the variability in bone tissue of different parts of the skeleton, and to analyze it by gender, as sensitivity to mechanical loading can diverge for boys and girls. We compared the effects of habitual physical activity (PA) and lean mass, as surrogates of weight-bearing and muscle forces, and of physical fitness (aerobic and muscle capacity of lower and upper limbs) on bone mineral content (BMC) and size of total body, lumbar spine, femoral neck, and 1/3 radius in 53 girls and 64 boys from 7.9 to 9.7 years of age. After controlling for bone age, body mass, body height, and calcium intake, lean mass was the most important predictor of bone size and/or mineral in both genders (p < 0.05), while habitual weight-bearing PA positively influenced BMC in boys (p < 0.05). The effect of muscle in bone was not determined by PA and fitness score did not explain bone variability. Femoral neck was the bone site more closely associated with mechanical loading factors; boys with a PA > 608 counts/min/day (~105 min/day of moderate and vigorous intensity) showed 13-20% more BMC than those with less physical activity, and girls with a lean mass >19 kg showed 12-19% more BMC than those with less lean mass. These findings suggest that lean mass was the most important predictor of bone size and/or mineralization in both genders, while habitual weight-bearing PA appears to positively impact on bone mineral in prepubertal boys and that both lean mass and PA need to be considered in physical education curricula and other health-enhancing programs.
Ryan, Zachary C.; Ketha, Hemamalini; McNulty, Melissa S.; McGee-Lawrence, Meghan; Craig, Theodore A.; Grande, Joseph P.; Westendorf, Jennifer J.; Singh, Ravinder J.; Kumar, Rajiv
2013-01-01
Inactivating mutations of the SOST (sclerostin) gene are associated with overgrowth and sclerosis of the skeleton. To determine mechanisms by which increased amounts of calcium and phosphorus are accreted to enable enhanced bone mineralization in the absence of sclerostin, we measured concentrations of calciotropic and phosphaturic hormones, and urine and serum calcium and inorganic phosphorus in mice in which the sclerostin (sost) gene was replaced by the β-D-galactosidase (lacZ) gene in the germ line. Knockout (KO) (sost−/−) mice had increased bone mineral density and content, increased cortical and trabecular bone thickness, and greater net bone formation as a result of increased osteoblast and decreased osteoclast surfaces compared with wild-type (WT) mice. β-Galactosidase activity was detected in osteocytes of sost KO mice but was undetectable in WT mice. Eight-week-old, male sost KO mice had increased serum 1α,25-dihydroxyvitamin D, decreased 24,25-dihydroxyvitamin D, decreased intact fibroblast growth factor 23, and elevated inorganic phosphorus concentrations compared with age-matched WT mice. 25-Hydroxyvitamin D 1α-hydroxylase cytochrome P450 (cyp27B1) mRNA was increased in kidneys of sost KO mice compared with WT mice. Treatment of cultured proximal tubule cells with mouse recombinant sclerostin decreased cyp27B1 mRNA transcripts. Urinary calcium and renal fractional excretion of calcium were decreased in sost KO mice compared with WT mice. Sost KO and WT mice had similar serum calcium and parathyroid hormone concentrations. The data show that sclerostin not only alters bone mineralization, but also influences mineral metabolism by altering concentrations of hormones that regulate mineral accretion. PMID:23530237
Ryan, Zachary C; Ketha, Hemamalini; McNulty, Melissa S; McGee-Lawrence, Meghan; Craig, Theodore A; Grande, Joseph P; Westendorf, Jennifer J; Singh, Ravinder J; Kumar, Rajiv
2013-04-09
Inactivating mutations of the SOST (sclerostin) gene are associated with overgrowth and sclerosis of the skeleton. To determine mechanisms by which increased amounts of calcium and phosphorus are accreted to enable enhanced bone mineralization in the absence of sclerostin, we measured concentrations of calciotropic and phosphaturic hormones, and urine and serum calcium and inorganic phosphorus in mice in which the sclerostin (sost) gene was replaced by the β-D-galactosidase (lacZ) gene in the germ line. Knockout (KO) (sost(-/-)) mice had increased bone mineral density and content, increased cortical and trabecular bone thickness, and greater net bone formation as a result of increased osteoblast and decreased osteoclast surfaces compared with wild-type (WT) mice. β-Galactosidase activity was detected in osteocytes of sost KO mice but was undetectable in WT mice. Eight-week-old, male sost KO mice had increased serum 1α,25-dihydroxyvitamin D, decreased 24,25-dihydroxyvitamin D, decreased intact fibroblast growth factor 23, and elevated inorganic phosphorus concentrations compared with age-matched WT mice. 25-Hydroxyvitamin D 1α-hydroxylase cytochrome P450 (cyp27B1) mRNA was increased in kidneys of sost KO mice compared with WT mice. Treatment of cultured proximal tubule cells with mouse recombinant sclerostin decreased cyp27B1 mRNA transcripts. Urinary calcium and renal fractional excretion of calcium were decreased in sost KO mice compared with WT mice. Sost KO and WT mice had similar serum calcium and parathyroid hormone concentrations. The data show that sclerostin not only alters bone mineralization, but also influences mineral metabolism by altering concentrations of hormones that regulate mineral accretion.
NASA Astrophysics Data System (ADS)
Vasconcellos, Kayla B.; McHugh, Sean M.; Dapsis, Katherine J.; Petty, Alexander R.; Gerdon, Aren E.
2013-09-01
Biomineralization of hydroxyapatite (Ca10(PO4)6(OH)2) is of significant importance in biomedical applications such as bone and dental repair, and biomimetic control of mineral formation may lead to more effective restorative procedures. Gold nanoparticles are functional scaffolds on which to assemble multi-component monolayers capable of mimicking protein activity in the templated synthesis of calcium phosphate. The goal of this research was to explore nanoparticle templates with mixed-monolayers of uncharged polar polyethylene glycol (PEG) molecules and highly charged polynucleotide and amino acid molecules in their ability to influence mineralization rates and mineral particle size and morphology. This research demonstrates through time-resolved optical density and dynamic light scattering measurements that the combination of tiopronin, PEG, and DNA presented on a nanoparticle surface decreases nanoparticle aggregation from 59 to 21 nm solvated radius, increases mineralization kinetics from 1.5 × 10-3 to 3.1 × 10-3 OD/min, and decreases mineral particle size from 685 to 442 nm average radius. FT-IR and TEM data demonstrate that mineralized material, while initially amorphous, transforms to a semi-crystalline material when guided by template interactions. This demonstrates that surface-tailored monolayer protected cluster scaffolds are successful and controllable mineralization templates with further potential for biomedical applications involving calcium phosphate and other biomaterials.
Pathogenesis and management of primary osteoporosis.
Bauwens, S F; Drinka, P J; Boh, L E
1986-08-01
The pathophysiology of primary osteoporosis and the various therapeutic regimens that have been used are reviewed. Osteoporosis is a major public health problem because the incidence of hip, wrist, and vertebral fractures associated with bone loss is high. Postmenopausal women are at increased risk for developing osteoporosis because bone mineral content is lower in women than in men, dietary calcium intake is frequently insufficient, intestinal absorption of calcium decreases with age, and the rate of bone loss accelerates at menopause. The efficacy of many single and combination therapies in preventing or treating osteoporosis has been studied. Differences in study design and diagnostic techniques and the heterogeneous nature of osteoporosis make evaluation of clinical trials difficult. Exercise helps to maintain skeletal mass, but amenorrhea caused by vigorous activity may be harmful. The efficacy of estrogen replacement therapy is documented best; many studies have shown that estrogens slow the rate of bone loss and reduce the incidence of fractures, but the association of estrogen use with endometrial cancer and breast cancer is of concern. Progesterones may protect against endometrial cancer, but undesirable effects of oral contraceptives have resulted in a hesitancy to use combination hormonal therapy. All adults should meet daily nutritional requirements for calcium, but this intake may be insufficient for elderly persons and is below recommended doses for treating osteoporosis. A daily intake of at least 1000-1500 mg of elemental calcium has been shown to slow the rate of bone loss. Nutritional requirements for vitamin D should be met, but benefits from pharmacologic doses have not been demonstrated. The role of fluoride, calcitonin, anabolic steroids, and vitamin D metabolites is unclear. Fluoride has the potential to increase bone mass, but effects on bone histology and fracture rates require further study. The major goals for the management of osteoporosis are maintenance of bone mass and prevention of fractures. An adequate intake of calcium and regular weight-bearing exercise are important preventive measures. Despite the documented effectiveness of estrogens, risks associated with long-term use are of concern.
Phase transitions in biogenic amorphous calcium carbonate.
Gong, Yutao U T; Killian, Christopher E; Olson, Ian C; Appathurai, Narayana P; Amasino, Audra L; Martin, Michael C; Holt, Liam J; Wilt, Fred H; Gilbert, P U P A
2012-04-17
Crystalline biominerals do not resemble faceted crystals. Current explanations for this property involve formation via amorphous phases. Using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), here we examine forming spicules in embryos of Strongylocentrotus purpuratus sea urchins, and observe a sequence of three mineral phases: hydrated amorphous calcium carbonate (ACC · H(2)O) → dehydrated amorphous calcium carbonate (ACC) → calcite. Unexpectedly, we find ACC · H(2)O-rich nanoparticles that persist after the surrounding mineral has dehydrated and crystallized. Protein matrix components occluded within the mineral must inhibit ACC · H(2)O dehydration. We devised an in vitro, also using XANES-PEEM, assay to identify spicule proteins that may play a role in stabilizing various mineral phases, and found that the most abundant occluded matrix protein in the sea urchin spicules, SM50, stabilizes ACC · H(2)O in vitro.
Phase transitions in biogenic amorphous calcium carbonate
Gong, Yutao U. T.; Killian, Christopher E.; Olson, Ian C.; Appathurai, Narayana P.; Amasino, Audra L.; Martin, Michael C.; Holt, Liam J.; Wilt, Fred H.; Gilbert, P. U. P. A.
2012-01-01
Crystalline biominerals do not resemble faceted crystals. Current explanations for this property involve formation via amorphous phases. Using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), here we examine forming spicules in embryos of Strongylocentrotus purpuratus sea urchins, and observe a sequence of three mineral phases: hydrated amorphous calcium carbonate (ACC·H2O) → dehydrated amorphous calcium carbonate (ACC) → calcite. Unexpectedly, we find ACC·H2O-rich nanoparticles that persist after the surrounding mineral has dehydrated and crystallized. Protein matrix components occluded within the mineral must inhibit ACC·H2O dehydration. We devised an in vitro, also using XANES-PEEM, assay to identify spicule proteins that may play a role in stabilizing various mineral phases, and found that the most abundant occluded matrix protein in the sea urchin spicules, SM50, stabilizes ACC·H2O in vitro. PMID:22492931
Children who avoid drinking cow milk have low dietary calcium intakes and poor bone health.
Black, Ruth E; Williams, Sheila M; Jones, Ianthe E; Goulding, Ailsa
2002-09-01
Information concerning the adequacy of bone mineralization in children who customarily avoid drinking cow milk is sparse. The objective was to evaluate dietary calcium intakes, anthropometric measures, and bone health in prepubertal children with a history of long-term milk avoidance. We recruited 50 milk avoiders (30 girls, 20 boys) aged 3-10 y by advertisement. We measured current dietary calcium intakes with a food-frequency questionnaire and body composition and bone mineral density with dual-energy X-ray absorptiometry and compared the results with those of 200 milk-drinking control children. The reasons for milk avoidance were intolerance (40%), bad taste (42%), and lifestyle choice (18%). Dietary calcium intakes were low (443 +/- 230 mg Ca/d), and few children consumed substitute calcium-rich drinks or mineral supplements. Although 9 children (18%) were obese, the milk avoiders were shorter (P < 0.01), had smaller skeletons (P < 0.01), had a lower total-body bone mineral content (P < 0.01), and had lower z scores (P < 0.05) for areal bone mineral density at the femoral neck, hip trochanter, lumbar spine, ultradistal radius, and 33% radius than did control children of the same age and sex from the same community. The z scores for volumetric (size-adjusted) bone mineral density (g/cm(3)) were -0.72 +/- 1.17 for the lumbar spine and -0.72 +/- 1.35 for the 33% radius (P < 0.001). Twelve children (24%) had previously broken bones. In growing children, long-term avoidance of cow milk is associated with small stature and poor bone health. This is a major concern that warrants further study.
Laurencin, Danielle; Wong, Alan; Chrzanowski, Wojciech; Knowles, Jonathan C; Qiu, Dong; Pickup, David M; Newport, Robert J; Gan, Zhehong; Duer, Melinda J; Smith, Mark E
2010-02-07
Despite the numerous studies of bone mineral, there are still many questions regarding the exact structure and composition of the mineral phase, and how the mineral crystals become organised with respect to each other and the collagen matrix. Bone mineral is commonly formulated as hydroxyapatite, albeit with numerous substitutions, and has previously been studied by (31)P and (1)H NMR, which has given considerable insight into the complexity of the mineral structure. However, to date, there has been no report of an NMR investigation of the other major component of bone mineral, calcium, nor of common minority cations like sodium. Here, direct analysis of the local environment of calcium in two biological apatites, equine bone (HB) and bovine tooth (CT), was carried out using both (43)Ca solid state NMR and Ca K-edge X-ray absorption spectroscopy, revealing important structural information about the calcium coordination shell. The (43)Ca delta(iso) in HB and CT is found to correlate with the average Ca-O bond distance measured by Ca K-edge EXAFS, and the (43)Ca NMR linewidths show that there is a greater distribution in chemical bonding around calcium in HB and CT, compared to synthetic apatites. In the case of sodium, (23)Na MAS NMR, high resolution 3Q-MAS NMR, as well as (23)Na{(31)P} REDOR and (1)H{(23)Na} R(3)-HMQC correlation experiments give the first direct evidence that some sodium is located inside the apatite phase in HB and CT, but with a greater distribution of environments compared to a synthetic sodium substituted apatite (Na-HA).
Frommelt, Lena; Bielohuby, Maximilian; Stoehr, Barbara J M; Menhofer, Dominik; Bidlingmaier, Martin; Kienzle, Ellen
2014-01-01
Ketogenic low-carbohydrate, high-fat (LCHF) diets reduce growth and bone mineral density in children with epilepsy and in rats. Part of this effect might be due to a reduced availability of calcium in high-fat diets. The aim of this study was to determine mineral digestibility by total collection method in LCHF diets compared with a chow diet and a standard high-fat diet (HFD, high in fat and carbohydrates). Twelve-wk-old male Wistar rats were pair-fed isoenergetic amounts of either six different LCHF diets based on tallow and casein (crude fat 75%-50%, crude protein 10%-35%), with chow or with a HFD diet. Mineral-to-energy ratio was matched in all diets. Circulating parathyroid hormone was measured by immunoassay. The apparent digestibility of calcium was reduced in all HFDs (high-fat diets, LCHF diets and the HFD diet) by at least 30% compared with the chow diet (P < 0.001). Fecal calcium excretion correlated positively with fecal fat excretion, presumably because of formation of calcium soaps. Apparent digestibility of phosphorous was higher in all HFDs. This resulted in a decrease of the ratio of apparently digested calcium to apparently digested phosphorous in all HFDs below a ratio of 1:1. Plasma parathyroid hormone was not affected by any diet. The alteration of apparent calcium and phosphorus digestibility may affect the impact of HFDs on bone metabolism. Copyright © 2014 Elsevier Inc. All rights reserved.
[Content of mineral elements in the diet of students of physical education faculty].
Novokshanova, A L; Nikitiyk, D B; Pozdniakov, A L
2013-01-01
Research of the diet of students of the Faculty of Physical Education found discrepancy of caloric content and correlation of macro- and micronutrients to physiological norms accompanied by a deficiency of some mineral elements. Thus, this research found discrepancy of a diet in caloric content and correlation of macro- and micronutrients to physiological norms. Calorie deficiency in both groups is caused for lack of all macro- and micronutrients, but mostly for lack of carbohydrates with an average glycemic index, fruit, and vegetables that have prebiotic properties and mineral-rich elements. Deficiency in the diet of young men 9.6% of the total protein and 23.5% of carbohydrates was accompanied for lack 15.5% of calcium. In the group of girls the results showed a decrease of the required amounts of calcium, magnesium and iron of 36.4; 7.5 and 1.5% respectively, which was displayed against a background of reducing the consumption of the total protein 25.1 and 36.0% of carbohydrates. As a result, basic nutrition of students practicing sports requires rationalization and adjustment. To improve the biological value of the diet it is advisable for students to use daily dairy products and other sources of animal protein in their diets. It is also necessary to introduce fruit and vegetables as a source of dietary fibers and mineral elements. Created in both groups deficiency of calcium and biologically high-grade proteins of animal origin can be eliminated by various dairy products in which calcium and phosphorus are in easily digestible form and in a balanced quantity. Despite the considerable amount of calcium in many foods (meat, bread, cereals, vegetables) calcium is assimilated with difficulty from these products. The exception is the calcium of milk, curd, cheese and other dairy products. The ration between calcium and phosphorus in milk is 1:1-1.4:1. For example, taking 0.5 liters of milk provides 600 mg of assimilable calcium intake.
Physical activity effects on bone metabolism.
Smith, E L; Gilligan, C
1991-01-01
The incidence of osteoporotic fractures rises exponentially with age and is increasing faster than the demographic increase in the aging population. Physical activity has great potential to reduce the risk for osteoporotic fractures. Three independent but interactive factors contribute to the risk of fractures: bone strength, the risk of falling, and the effectiveness of neuromuscular response that protects the skeleton from injury. Exercise can reduce fracture risk not only by preventing bone loss, but by decreasing the risk of falling and the force of impact by improving strength, flexibility, balance, and reaction time. Extreme inactivity causes rapid bone loss of up to 40%, while athletic activity results in bone hypertrophy of up to 40%. Exercise intervention programs have reduced bone loss or increased bone mass in both men and women of various ages and initial bone status. These benefits have been shown for arm bone mineral content, total body calcium, spine, calcium bone index, tibia, and calcaneus. In both middle-aged and elderly women, physical activity intervention reduced bone loss or increased bone mass. The mechanisms for maintenance of skeletal integrity rely on a cellular response to hormonal and mechanical load stimuli. Studies in animal models show that training affects cellular activity. In osteoporotics, cellular erosion is increased and mineral apposition rate (MAR) decreased compared with normal age-matched controls. In contrast to this, sows trained on a treadmill 20 min per day for 20 weeks had greater active periosteal surface, periosteal MAR, and osteonal MAR than untrained sows.
Application of Quantitative Analytical Electron Microscopy to the Mineral Content of Insect Cuticle
NASA Astrophysics Data System (ADS)
Rasch, Ron; Cribb, Bronwen W.; Barry, John; Palmer, Christopher M.
2003-04-01
Quantification of calcium in the cuticle of the fly larva Exeretonevra angustifrons was undertaken at the micron scale using wavelength dispersive X-ray microanalysis, analytical standards, and a full matrix correction. Calcium and phosphorus were found to be present in the exoskeleton in a ratio that indicates amorphous calcium phosphate. This was confirmed through electron diffraction of the calcium-containing tissue. Due to the pragmatic difficulties of measuring light elements, it is not uncommon in the field of entomology to neglect the use of matrix corrections when performing microanalysis of bulk insect specimens. To determine, firstly, whether such a strategy affects the outcome and secondly, which matrix correction is preferable, phi-rho (z) and ZAF matrix corrections were contrasted with each other and without matrix correction. The best estimate of the mineral phase was found to be given by using the phi-rho (z) correction. When no correction was made, the ratio of Ca to P fell outside the range for amorphous calcium phosphate, possibly leading to flawed interpretation of the mineral form when used on its own.
Analysis of mineral matrices of planetary soil analogues from the Utah Desert
NASA Astrophysics Data System (ADS)
Kotler, J. M.; Quinn, R. C.; Foing, B. H.; Martins, Z.; Ehrenfreund, P.
2011-07-01
Phyllosilicate minerals and hydrated sulphate minerals have been positively identified on the surface of Mars. Studies conducted on Earth indicate that micro-organisms influence various geochemical and mineralogical transitions for the sulphate and phyllosilicate minerals. These minerals in turn provide key nutrients to micro-organisms and influence microbial ecology. Therefore, the presence of these minerals in astrobiology studies of Earth-Mars analogue environments could help scientists better understand the types and potential abundance of micro-organisms and/or biosignatures that may be encountered on Mars. Bulk X-ray diffraction of samples collected during the EuroGeoMars 2009 campaign from the Mancos Shale, the Morrison and the Dakota formations near the Mars Desert Research Station in Utah show variable but common sedimentary mineralogy with all samples containing quantities of hydrated sulphate minerals and/or phyllosilicates. Analysis of the clay fractions indicate that the phyllosilicates are interstratified illite-smectites with all samples showing marked changes in the diffraction pattern after ethylene glycol treatment and the characteristic appearance of a solvated peak at ˜17 Å. The smectite phases were identified as montmorillonite and nontronite using a combination of the X-ray diffraction data and Fourier-Transform Infrared Spectroscopy. The most common sulphate mineral in the samples is hydrated calcium sulphate (gypsum), although one sample contained detectable amounts of strontium sulphate (celestine). Carbonates detected in the samples are variable in composition and include pure calcium carbonate (calcite), magnesium-bearing calcium carbonate (dolomite), magnesium, iron and manganese-bearing calcium carbonate (ankerite) and iron carbonate (siderite). The results of these analyses when combined with organic extractions and biological analysis should help astrobiologists and planetary geologists better understand the potential relationships between mineralogy and microbiology for planetary missions.
Van den Bussche, Karen; Herrmann, Diana; De Henauw, Stefaan; Kourides, Yiannis A.; Lauria, Fabio; Marild, Staffan; Molnár, Dénes; Moreno, Luis A.; Veidebaum, Toomas; Ahrens, Wolfgang; Sioen, Isabelle
2016-01-01
This study investigates differences and associations between urinary mineral concentrations and calcaneal bone measures assessed by quantitative ultrasonography (QUS) in 4322 children (3.1–11.9 years, 50.6% boys) from seven European countries. Urinary mineral concentrations and calcaneal QUS parameters differed significantly across countries. Clustering revealed a lower stiffness index (SI) in children with low and medium urinary mineral concentrations, and a higher SI in children with high urinary mineral concentrations. Urinary sodium (uNa) was positively correlated with urinary calcium (uCa), and was positively associated with broadband ultrasound attenuation and SI after adjustment for age, sex and fat-free mass. Urinary potassium (uK) was negatively correlated with uCa but positively associated with speed of sound after adjustment. No association was found between uCa and QUS parameters after adjustment, but when additionally adjusting for uNa, uCa was negatively associated with SI. Our findings suggest that urinary mineral concentrations are associated with calcaneal QUS parameters and may therefore implicate bone properties. These findings should be confirmed in longitudinal studies that include the food intake and repeated measurement of urinary mineral concentrations to better estimate usual intake and minimize bias. PMID:27164120
Aptel, I; Cance-Rouzaud, A; Grandjean, H
1999-05-01
Although the main source of dietary calcium is dairy products, the calcium contained in mineral water, which is as available as that of milk, could provide a valuable source of calcium. We analyzed the data from the EPIDOS multicenter study to evaluate the relationship between both dietary calcium and that supplied by drinking water and bone density measured at the femoral neck by dual-energy X-ray absorptiometry. The study included 4434 women over 75 years of age who had not received any treatment likely to interfere with calcium metabolism. A significant correlation was found between total calcium intake and bone density at the femoral neck (r = 0.10, p < 0. 001). After adjustment for the main variables influencing bone density, an increase of 100 mg/day in calcium from drinking water was associated to a 0.5% increase in femoral bone density, while a similar increase in dietary calcium from other sources only led to a 0.2% increase; however, this difference was not significant. The consumption of calcium-rich mineral water may be of interest, especially in older women who consume little calcium from dairy products.
Baier, Martin; Staudt, Patric; Klein, Roman; Sommer, Ulrike; Wenz, Robert; Grafe, Ingo; Meeder, Peter Jürgen; Nawroth, Peter P; Kasperk, Christian
2013-06-07
Calcium phosphate cements are used frequently in orthopedic and dental surgeries. Strontium-containing drugs serve as systemic osteoblast-activating medication in various clinical settings promoting mechanical stability of the osteoporotic bone. Strontium-containing calcium phosphate cement (SPC) and calcium phosphate cement (CPC) were compared regarding their local and systemic effects on bone tissue in a standard animal model for osteoporotic bone. A bone defect was created in the distal femoral metaphysis of 60 ovariectomized Sprague-Dawley rats. CPC and SPC were used to fill the defects in 30 rats in each group. Local effects were assessed by histomorphometry at the implant site. Systemic effects were assessed by bone mineral density (BMD) measurements at the contralateral femur and the spine. Faster osseointegration and more new bone formation were found for SPC as compared to CPC implant sites. SPC implants exhibited more cracks than CPC implants, allowing more bone formation within the implant. Contralateral femur BMD and spine BMD did not differ significantly between the groups. The addition of strontium to calcium phosphate stimulates bone formation in and around the implant. Systemic release of strontium from the SPC implants did not lead to sufficiently high serum strontium levels to induce significant systemic effects on bone mass in this rat model.
High sodium chloride intake is associated with low bone density in calcium stone-forming patients.
Martini, L A; Cuppari, L; Colugnati, F A; Sigulem, D M; Szejnfeld, V L; Schor, N; Heilberg, I P
2000-08-01
Although renal stone disease has been associated with reduced bone mass, the impact of nutrient intake on bone loss is unknown. The present study was undertaken to investigate the influence of nutrient intake on bone density of 85 calcium stone-forming (CSF) patients (47 male and 38 premenopausal females) aged 41+/-11 years (X+/-SD). Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry at the lumbar spine (L2-L4) and femoral neck sites, and low BMD was defined as a T score < -1 (WHO criteria). A 4-day dietary record and a 24-hour urine sample were obtained from each patient for the assessment of nutrient intake and urinary calcium (U(Ca)), sodium (U(Na)), phosphate and creatinine excretion. Forty-eight patients (56%) presented normal BMD and 37 (44%) low BMD. There were no statistical differences regarding age, weight, height, body mass index, protein, calcium and phosphorus intakes between both groups. The mean U(Ca), phosphorus and nitrogen appearance also did not differ between groups. However, there was a higher percentage of hypercalciuria among low vs normal BMD patients (62 vs 33%, p < 0.05). Low BMD patients presented a higher mean sodium chloride (NaCl) intake and excretion (UNa) than normal BMD (14+/-5 vs 12+/-4 g/day and 246+/-85 vs 204+/-68 mEq/day, respectively p < 0.05). The percentage of patients presenting NaCl intake > or = 16 g/day was also higher among low vs normal BMD patients (35 vs 12%, p < 0.05). After adjustment for calcium and protein intakes, age, weight, body mass index, urinary calcium, citrate and uric acid excretion, and duration of stone disease, multiple-regression analysis showed that a high NaCl intake (> or = 16 g/day) was the single variable that was predictive of risk of low bone density in CSF patients (odds ratio = 3.8). These data suggest that reducing salt intake should be recommended for CSF patients presenting hypercalciuria and osteopenia.
NASA Technical Reports Server (NTRS)
Berggren, Mark; Zubrin, Robert; Bostwick-White, Emily
2013-01-01
The Lunar Sulfur Capture System (LSCS) protects in situ resource utilization (ISRU) hardware from corrosion, and reduces contaminant levels in water condensed for electrolysis. The LSCS uses a lunar soil sorbent to trap over 98 percent of sulfur gases and about two-thirds of halide gases evolved during hydrogen reduction of lunar soils. LSCS soil sorbent is based on lunar minerals containing iron and calcium compounds that trap sulfur and halide gas contaminants in a fixed-bed reactor held at temperatures between 250 and 400 C, allowing moisture produced during reduction to pass through in vapor phase. Small amounts of Earth-based polishing sorbents consisting of zinc oxide and sodium aluminate are used to reduce contaminant concentrations to one ppm or less. The preferred LSCS configuration employs lunar soil beneficiation to boost concentrations of reactive sorbent minerals. Lunar soils contain sulfur in concentrations of about 0.1 percent, and halogen compounds including chlorine and fluorine in concentrations of about 0.01 percent. These contaminants are released as gases such as H2S, COS, CS2,HCl, and HF during thermal ISRU processing with hydrogen or other reducing gases. Removal of contaminant gases is required during ISRU processing to prevent hardware corrosion, electrolyzer damage, and catalyst poisoning. The use of Earth-supplied, single-use consumables to entirely remove contaminants at the levels existing in lunar soils would make many ISRU processes unattractive due to the large mass of consumables relative to the mass of oxygen produced. The LSCS concept of using a primary sorbent prepared from lunar soil was identified as a method by which the majority of contaminants could be removed from process gas streams, thereby substantially reducing the required mass of Earth-supplied consumables. The LSCS takes advantage of minerals containing iron and calcium compounds that are present in lunar soil to trap sulfur and halide gases in a fixedbed reactor downstream of an in-ISRU process such as hydrogen reduction. The lunar-soil-sorbent trap is held at a temperature significantly lower than the operating temperature of the hydrogen reduction or other ISRU process in order to maximize capture of contaminants, but is held at a high enough temperature to allow moisture to pass through without condensing. The lunar soil benefits from physical beneficiation to remove ultrafine particles (to reduce pressure drop through a fixed bed reactor) and to upgrade concentrations of iron and/or calcium compounds (to improve reactivity with gaseous contaminants).
Endo, Hitoshi; Schwahn, Dietmar; Cölfen, Helmut
2004-05-15
The role of the double-hydrophilic block copolymer poly(ethylen glycol)-block-poly(methacrylic acid) (PEG-b-PMAA) on the morphogenesis of calcium carbonate (CaCO3) was studied by applying the contrast variation small angle neutron scattering technique. The morphology and size of CaCO3 crystals is strongly affected by the addition of PEG-b-PMAA. In order to determine the partial scattering functions of the polymer and CaCO3 mineral, we developed both an experimental and theoretical approach with a sophisticated method of their determination from the scattering intensity. Partial scattering functions give detailed information for each component. In particular, the partial scattering function of the polymer, Spp, shows a monotonic slope with Q(-2 to -3) where the scattering vector Q is low (Q < 0.01 Angstrom(-1)), which is a clear evidence that the polymer within the CaCO3 mineral has a mass fractal dimension. The other partial scattering functions reflected the geometry of the CaCO3 particles or the "interaction" of polymer and CaCO3 on a microscopic scale, which leads to a coherent view with Spp.
The usefulness of densitometry in predicting the composition and fragility of urolithiasis.
Argüelles-Salido, Enrique; Lozano-Blasco, Jose Maria; Subira-Rios, Jorge; Bernardo-Villar, Pastora; Podio-Lora, Virtudes; Campoy-Martínez, Pedro; Vazquez-Albertino, Ricardo; Medina-Lopez, Rafael
2014-04-01
The choice of ideal treatment for a given lithiasis is a crucial factor for its success, minimizing the number of interventions and complications. Previous determination of stone composition and its fragility is desirable, to predict its behavior during extracorporeal shock wave lithotripsy and for evaluation of its appropriateness, or to set the indication for other techniques. To determine the role of densitometry in the prediction of composition and fragility of urinary lithiasis undergoing SWL. Experimental prospective, blinded, in vitro study using 193 urinary calculi of known composition : monohydrated calcium oxalate, mixed calcium oxalate, uric acid, and calcium carbonate, obtained from spontaneous passage or surgery. Densitometry and SWL were performed on them. We compare the mineral composition of the stone and mineral density of each composition group to check if they are characteristic of each type and correlate these parameters with the energy dose required to fragment them down to a given fragment size. Only 53 out of 193 stones showed valuable data. Calcium carbonate was the composition showing grater mineral content and density (1,24 gr and 0,47 gr/cm2), followed by mixed oxalate (0,51/0,26) and uric acid (0,52/ 0,15), finishing with the monohydrate calcium oxalate group (0,32/0,05).Only the comparison between calcium carbonate and monohydrated calcium oxalate showed statistically significant results (p<0,05). Correlation coefficients between mineral content (0,347) and density (0,424) and the energy used for stone fragmentation to a given fragment size were statistically significant (p<0,05) CONCLUSIONS: In our study, the use of densitometry to determine stone composition and lithiasic fragility did not show conclusive results due to the limited number of calculi tested. Nevertheless, there are signs that, with a different study design , more practically useful results could be achieved.
Wohlt, J E; Ritter, D E; Evans, J L
1986-11-01
Three supplemental sources of inorganic calcium (calcite flour, aragonite, albacar), each differing in particle size and rate of reactivity, provided .6 or .9% calcium in corn silage:grain (1:1 dry matter) diets of high producing dairy cows. All cows were fed calcite flour at .6% calcium during the first 4 wk of lactation. On d 29 of lactation 5 cows were assigned to each of the six diets. Peak milk yield paralleled dry matter intake and was higher when calcite flour and aragonite provided .9% calcium, intermediate when all sources provided .6% calcium, and lower when albacar provided .9% calcium. However, adaptations to calcium source and to particle sizes of a calcium source (.35 to 1190 mu) were made within 40 d by lactating Holsteins. Starch increased and pH decreased in feces of cows fed albacar. Increasing calcium in the diet provided more buffering capacity in the gastrointestinal tract. True absorption of calcium did not differ from linearity due to source when fecal calcium was regressed on ingested calcium but did vary as a function of diet percentage. Thus, calcium retention was increased when cows were fed .9 vs. .6% calcium. These data suggest that a slow reacting (coarser) inorganic calcium source should be fed at a higher amount to optimize feed intake and milk production.
Aguilera-Barreiro, María de Los Angeles; Rivera-Márquez, José Alberto; Trujillo-Arriaga, Héctor Miguel; Tamayo Y Orozco, Juan Alfredo; Barreira-Mercado, Eduardo; Rodríguez-García, Mario E
2013-01-01
The intake of dehydrated nopal (DN) at a high stage of maturity along with high calcium content could improve bone mineral density (BMD) and calciuria and thus prevent osteoporosis. To evaluate the effect of calcium intake from a vegetable source (DN) on BMD and calciuria covering a 2-year period in menopausal and non-menopausal women with low bone mass (LBM). The study was quasi-experimental, blinded, and randomized, and included 131 Mexican women aged 35-55. Urinary calcium/creatinine index (CCI) was determined; BMD was analyzed on lumbar spine and total hip regions. Four groups were studied: Control group (CG), women with normocalciuria and a minimum dose of DN; experimental group 1 (EG1), women with hypercalciuria and a minimum dose of DN; experimental group 2 (EG2), women with hypercalciuria, and a maximum dose of DN; and normal group (NG) for reference in BMD. After the first semester of treatment, calciuria levels in women from both experimental groups returned to normal, remaining constant for the rest of the treatment. The percentage difference in BMD increased in the total hip region in the CG (pre 4.5% and post 2.1%) and EG2 (pre 1.8% and post 2.5%) groups significantly in comparison to NG and EG1, which exhibited a significant decrease in their BMD. BMD increased only for the lumbar region in the EG2 group (premenopausal). The use of a vegetable calcium source such as nopal improves BMD in women with LBM in the total hip and lumbar spine regions principally in the premenopausal women, maintaining constant and normal calciuria levels.
Aguilera-Barreiro, María de los Angeles; Rivera-Márquez, José Alberto; Trujillo-Arriaga, Héctor Miguel; Tamayo y Orozco, Juan Alfredo; Barreira-Mercado, Eduardo; Rodríguez-García, Mario E
2013-01-01
Background The intake of dehydrated nopal (DN) at a high stage of maturity along with high calcium content could improve bone mineral density (BMD) and calciuria and thus prevent osteoporosis. Objective To evaluate the effect of calcium intake from a vegetable source (DN) on BMD and calciuria covering a 2-year period in menopausal and non-menopausal women with low bone mass (LBM). Methods The study was quasi-experimental, blinded, and randomized, and included 131 Mexican women aged 35–55. Urinary calcium/creatinine index (CCI) was determined; BMD was analyzed on lumbar spine and total hip regions. Four groups were studied: Control group (CG), women with normocalciuria and a minimum dose of DN; experimental group 1 (EG1), women with hypercalciuria and a minimum dose of DN; experimental group 2 (EG2), women with hypercalciuria, and a maximum dose of DN; and normal group (NG) for reference in BMD. Results After the first semester of treatment, calciuria levels in women from both experimental groups returned to normal, remaining constant for the rest of the treatment. The percentage difference in BMD increased in the total hip region in the CG (pre 4.5% and post 2.1%) and EG2 (pre 1.8% and post 2.5%) groups significantly in comparison to NG and EG1, which exhibited a significant decrease in their BMD. BMD increased only for the lumbar region in the EG2 group (premenopausal). Conclusion The use of a vegetable calcium source such as nopal improves BMD in women with LBM in the total hip and lumbar spine regions principally in the premenopausal women, maintaining constant and normal calciuria levels. PMID:23704856
Kaste, S C; Qi, A; Smith, K; Surprise, H; Lovorn, E; Boyett, J; Ferry, R J; Relling, M V; Shurtleff, S A; Pui, C H; Carbone, L; Hudson, M M; Ness, K K
2014-05-01
We sought to improve lumbar spine bone mineral density (LS-BMD) in long-term survivors of childhood acute lymphoblastic leukemia (ALL) using calcium and cholecalciferol supplementation. This double-blind, placebo-controlled trial randomized 275 participants (median age, 17 [9-36.1] years) with age- and gender-specific LS-BMD Z-scores <0 to receive nutritional counseling with supplementation of 1,000 mg/day calcium and 800 International Unit cholecalciferol or placebo for 2 years. The primary outcome was change in LS-BMD assessed by quantitative computerized tomography (QCT) at 24 months. Linear regression models were employed to identify the baseline risk factors for low LS-BMD and to compare LS-BMD outcomes. Pre-randomization LS-BMD below the mean was associated with male gender (P = 0.0024), White race (P = 0.0003), lower body mass index (P < 0.0001), and cumulative glucocorticoid doses of ≥ 5,000 mg (P = 0.0012). One hundred eighty-eight (68%) participants completed the study; 77% adhered to the intervention. Mean LS-BMD change did not differ between survivors randomized to supplements (0.33 ± 0.57) or placebo (0.28 ± 0.56). Participants aged 9-13 years and those 22-35 years had the greatest mean increases in LS-BMD (0.50 ± 0.66 and 0.37 ± 0.23, respectively). Vitamin D insufficiency (serum 25[OH]D <30 ng/ml) found in 296 (75%), was not associated with LS-BMD outcomes (P = 0.78). Cholecalciferol and calcium supplementation provides no added benefit to nutritional counseling for improving LS-BMD among adolescent and young adult survivors of ALL (93% of whom had LS-BMD Z-scores above the mean at study entry). © 2014 Wiley Periodicals, Inc.
Shariati-Bafghi, Seyedeh-Elaheh; Nosrat-Mirshekarlou, Elaheh; Karamati, Mohsen; Rashidkhani, Bahram
2014-01-01
Findings of studies on the link between dietary acid-base balance and bone mass are relatively mixed. We examined the association between dietary acid-base balance and bone mineral density (BMD) in a sample of Iranian women, hypothesizing that a higher dietary acidity would be inversely associated with BMD, even when dietary calcium intake is adequate. In this cross-sectional study, lumbar spine and femoral neck BMDs of 151 postmenopausal women aged 50-85 years were measured using dual-energy x-ray absorptiometry. Dietary intakes were assessed using a validated food frequency questionnaire. Renal net acid excretion (RNAE), an estimate of acid-base balance, was then calculated indirectly from the diet using the formulae of Remer (based on dietary intakes of protein, phosphorus, potassium, and magnesium; RNAERemer) and Frassetto (based on dietary intakes of protein and potassium; RNAEFrassetto), and was energy adjusted by the residual method. After adjusting for potential confounders, multivariable adjusted means of the lumbar spine BMD of women in the highest tertiles of RNAERemer and RNAEFrassetto were significantly lower than those in the lowest tertiles (for RNAERemer: mean difference -0.084 g/cm2; P=0.007 and for RNAEFrassetto: mean difference -0.088 g/cm2; P=0.004). Similar results were observed in a subgroup analysis of subjects with dietary calcium intake of >800 mg/day. In conclusion, a higher RNAE (i. e. more dietary acidity), which is associated with greater intake of acid-generating foods and lower intake of alkali-generating foods, may be involved in deteriorating the bone health of postmenopausal Iranian women, even in the context of adequate dietary calcium intake.
Composition and origin of PM10 in Cape Verde: Characterization of long-range transport episodes
NASA Astrophysics Data System (ADS)
Salvador, P.; Almeida, S. M.; Cardoso, J.; Almeida-Silva, M.; Nunes, T.; Cerqueira, M.; Alves, C.; Reis, M. A.; Chaves, P. C.; Artíñano, B.; Pio, C.
2016-02-01
A receptor modelling study was performed to identify source categories and their contributions to the PM10 total mass at the Cape Verde archipelago. Trajectory statistical methods were also used to characterize the main atmospheric circulation patterns causing the transport of air masses and to geographically identify the main potential source areas of each PM10 source category. Our findings point out that the variability of the PM10 levels at Cape Verde was prompted by the advections of African mineral dust. The mineral dust load was mainly composed by clay-silicates mineral derived elements (22% of the PM10 total mass on average) with lower amounts of carbonates (9%). A clear northward gradient was observed in carbonates concentration that illustrates the differences in the composition according to the source regions of mineral dust. Mineral dust was frequently linked to industrial emissions from crude oil refineries, fertilizer industries as well as oil and coal power plants, located in the northern and north-western coast of the African continent (29%). Sea salt was also registered in the PM10 mass during most part of the sampling period, with a lower impact in the PM10 levels than the mineral dust one (26%). Combustion aerosols (6%) reached the highest mean values in summer as a consequence of the emissions from local-regional sources. Biomass burning aerosols produced from October to November in sub-sahelian latitudes, had a clear influence in the content of elemental carbon (EC) recorded at Cape Verde but a small impact in the PM10 total mass levels. A minor contribution to the PM10 mass has been associated to secondary inorganic compounds-SIC. Namely, ammonium sulfate and nitrate (SIC 1-5%) and calcium sulfate and nitrate (SIC 2-3%). The main origin of SIC 1 was attributed to emissions of SO2 and NOx from industrial sources located in the northern and north-western African coast and from wildfires produced in the continent. SIC 2 had a clear regional origin in the summer period. However, in the winter period there were probably contributions of soil emissions of evaporate minerals from regions of eastern Algeria. The location of Cape Verde in the Atlantic Ocean at subtropical latitudes, and the absence of relevant local sources of anthropogenic atmospheric pollutants, becomes this archipelago, a perfect site to study the impact of external contributions on the background levels of PM10 registered over the north-eastern tropical Atlantic.
Li, Xiaoran; Xie, Jingwei; Yuan, Xiaoyan; Xia, Younan
2008-12-16
Electrospinning was employed to fabricate fibrous scaffolds of poly(epsilon-caprolactone) in the form of nonwoven mats. The surfaces of the fibers were then coated with gelatin through layer-by-layer self-assembly, followed by functionalization with a uniform coating of bonelike calcium phosphate by mineralization in the 10 times concentrated simulated body fluid for 2 h. Transmission electron microscopy, water contact angle, and scanning electron microscopy measurements confirmed the presence of gelatin and calcium phosphate coating layers, and X-ray diffraction results suggested that the deposited mineral phase was a mixture of dicalcium phosphate dehydrate (a precursor to apatite) and apatite. It was also demonstrated that the incorporation of gelatin promoted nucleation and growth of calcium phosphate. The porous scaffolds could mimic the structure, composition, and biological function of bone extracellular matrix. It was found that the preosteoblastic MC3T3-E1 cells attached, spread, and proliferated well with a flat morphology on the mineralized scaffolds. The proliferation rate of the cells on the mineralized scaffolds was significantly higher (by 1.9-fold) than that on the pristine fibrous scaffolds after culture for 7 days. These results indicated that the hybrid system containing poly(epsilon-caprolactone), gelatin, and calcium phosphate could serve as a new class of biomimetic scaffolds for bone tissue engineering.
Significance of serum levels of vitamin D and some related minerals in breast cancer patients
Abdelgawad, Iman A; El-Mously, Rawya H; Saber, Magdy M; Mansour, Ossama A; Shouman, Samia A
2015-01-01
Vitamin D and calcium are involved in a wide range of proliferation, apoptosis and cell signaling activities in the body. Suboptimal concentrations may lead to cancer development. The role of phosphate in cancer metabolism is particularly relevant in breast cancer while, magnesium deficiency favors DNA mutations leading to carcinogenesis. Objectives: To determine serum levels of vitamin D, calcium, phosphorus, magnesium, and parathormone in female breast cancer patients and to assess their association with some prognostic factors in breast cancer. Design and methods: This study is done on 98 newly diagnosed female breast cancer patients and 49 age matched apparently healthy female volunteers as controls. Serum samples from all patients and controls were subjected to 25-OH Vit D, calcium, phosphorus, magnesium, and parathormone measurements. Results: In the breast cancer group, the median serum levels of 25-OH Vit D were 15 ng/ml, while it was 21 ng/ml in the control group. Levels of 25-OH Vit D and other tested minerals were significantly lower while calcium:magnesium (Ca:Mg) ratio, and calcium:phosphorus (Ca:P) ratio were significantly higher in the breast cancer group. Significant negative correlation was detected between phosphorus and calcium, ionized calcium , calcium magnesium ratio, and calcium phosphorus ratio. Conclusion: It is not only the deficient levels of Vit D and other related minerals, but the combination of the abnormal levels of all the studied parameters that might contribute to the development of cancer. Further studies with larger number of patient are needed. PMID:26097595
Tsanzi, Embedzayi; Light, Heather R; Tou, Janet C
2008-05-01
Consumption of sugar beverages has increased among adolescents. Additionally, the replacement of sucrose with high fructose corn syrup (HFCS) as the predominant sweetener has resulted in higher fructose intake. Few studies have investigated the effect of drinking different sugar-sweetened beverages on bone, despite suggestions that sugar consumption negatively impacts mineral balance. The objective of this study was to determine the effect of drinking different sugar-sweetened beverages on bone mass and strength. Adolescent (age 35d) female Sprague-Dawley rats were randomly assigned (n=8-9/group) to consume deionized distilled water (ddH2O, control) or ddH2O containing 13% w/v glucose, sucrose, fructose or high fructose corn syrup (HFCS-55) for 8weeks. Tibia and femur measurements included bone morphometry, bone turnover markers, determination of bone mineral density (BMD) and bone mineral content (BMC) by dual energy X-ray absorptiometry (DXA) and bone strength by three-point bending test. The effect of sugar-sweetened beverage consumption on mineral balance, urinary and fecal calcium (Ca) and phosphorus (P) was measured by inductively coupled plasma optical emission spectrometry. The results showed no difference in the bone mass or strength of rats drinking the glucose-sweetened beverage despite their having the lowest food intake, but the highest beverage and caloric consumption. Only in comparisons among the rats provided sugar-sweetened beverage were femur and tibia BMD lower in rats drinking the glucose-sweetened beverage. Differences in bone and mineral measurements appeared most pronounced between rats drinking glucose versus fructose-sweetened beverages. Rats provided the glucose-sweetened beverage had reduced femur and tibia total P, reduced P and Ca intake and increased urinary Ca excretion compared to the rats provided the fructose-sweetened beverage. The results suggested that glucose rather than fructose exerted more deleterious effects on mineral balance and bone.
Connective Tissue Mineralization in Abcc6−/− Mice, a Model for Pseudoxanthoma Elasticum
Kavukcuoglu, N. Beril; Li, Qiaoli; Pleshko, Nancy; Uitto, Jouni
2012-01-01
Pseudoxanthoma elasticum (PXE) is a heritable multisystem disorder characterized by ectopic mineralization. However, the structure of the mineral deposits, their interactions with the connective tissue matrix, and the details of the progressive maturation of the mineral crystals are currently unknown. In this study, we examined the mineralization processes in Abcc6−/− mice, a model system for PXE, by energy dispersive X-ray, and Fourier transform infrared imaging spectroscopy (FT-IRIS). The results indicated that the principal components of the mineral deposits were calcium and phosphate which co-localized within the histologically demonstrable lesions determined by topographic mapping. The Ca/P ratio increased in samples with progressive mineralization reaching the value comparable to that in endochondral bone. A progressive increase in mineralization was also reflected by increased mineral-to-matrix ratio determined by FT-IRIS. Determination of the mineral phases by FT-IRIS suggested progressive maturation of the mineral deposits from amorphous calcium phosphate to hydroxyapatite. These results provide critical information of the mechanisms of mineralization in PXE, with potential pharmacologic implications. PMID:22421595
2011-01-01
Background High protein diet has been known to cause metabolic acidosis, which is manifested by increased urinary excretion of nitrogen and calcium. Bodybuilders habitually consumed excessive dietary protein over the amounts recommended for them to promote muscle mass accretion. This study investigated the metabolic response to high protein consumption in the elite bodybuilders. Methods Eight elite Korean bodybuilders within the age from 18 to 25, mean age 21.5 ± 2.6. For data collection, anthropometry, blood and urinary analysis, and dietary assessment were conducted. Results They consumed large amounts of protein (4.3 ± 1.2 g/kg BW/day) and calories (5,621.7 ± 1,354.7 kcal/day), as well as more than the recommended amounts of vitamins and minerals, including potassium and calcium. Serum creatinine (1.3 ± 0.1 mg/dl) and potassium (5.9 ± 0.8 mmol/L), and urinary urea nitrogen (24.7 ± 9.5 mg/dl) and creatinine (2.3 ± 0.7 mg/dl) were observed to be higher than the normal reference ranges. Urinary calcium (0.3 ± 0.1 mg/dl), and phosphorus (1.3 ± 0.4 mg/dl) were on the border of upper limit of the reference range and the urine pH was in normal range. Conclusions Increased urinary excretion of urea nitrogen and creatinine might be due to the high rates of protein metabolism that follow high protein intake and muscle turnover. The obvious evidence of metabolic acidosis in response to high protein diet in the subjects with high potassium intake and intensive resistance exercise were not shown in this study results. However, this study implied that resistance exercise with adequate mineral supplementation, such as potassium and calcium, could reduce or offset the negative effects of protein-generated metabolic changes. This study provides preliminary information of metabolic response to high protein intake in bodybuilders who engaged in high-intensity resistance exercise. Further studies will be needed to determine the effects of the intensity of exercise and the level of mineral intakes, especially potassium and calcium, which have a role to maintain acid-base homeostasis, on protein metabolism in large population of bodybuilders. PMID:21722409
Astronaut Bones: Stable Calcium Isotopes in Urine as a Biomarker of Bone Mineral Balance
NASA Astrophysics Data System (ADS)
Skulan, J.; Gordon, G. W.; Romaniello, S. J.; Anbar, A. D.; Smith, S. M.; Zwart, S.
2016-12-01
Bone loss is a common health concern, in conditions ranging from osteoporosis to cancer. Bone loss due to unloading is also an important health issue for astronauts. We demonstrate stable calcium isotopes, a tool developed in geochemistry, are capable of detecting real-time quantitative changes in net bone mineral balance (BMB) using serum and urine [1]. We validated this technique by comparing with DEXA and biomarker data in subjects during bed rest, a ground-based analog of space flight effects [2-4]. We now apply this tool to assess changes in astronauts' BMB before, during and after 4-6 month space missions. There is stable isotope fractionation asymmetry between bone formation and resorption. During bone formation there is a mass-dependent preference for "lighter" calcium isotopes to be removed from serum and incorporated into bone mineral. During bone resorption, there is no measurable isotopic discrimination between serum and bone. Hence, when bone formation rates exceed that of resorption, serum and urine become isotopically "heavy" due to the sequestration of "light" calcium in bone. Conversely, when bone resorption exceeds bone formation, serum and urine become isotopically "light" due to the release of the sequestered light calcium from bone. We measured Ca isotopes in urine of thirty International Space Station astronauts. Average Ca isotope values in astronauts' urine shift isotopically lighter during microgravity, consistent with negative net BMB. Within a month of return to Earth, astronauts returned to within error of their δ44Ca value prior to departure. Urine samples from astronauts testing bone loss countermeasures showed bisphosphonates provide a viable pharmacological countermeasure. Some, but not all, individuals appear able to resist bone loss through diet and intensive resistive exercise alone. This is a promising new technique for monitoring BMB in astronauts, and hopefully someday on the way to/from Mars, this also has important clinical applications for human health and terrestrial medicine [5]. REFERENCES [1] Morgan, J.L. et al (2011) Anal Chem 83, 6956-6962. [2] Skulan, J.L. et al. (2007) Clin Chem 53, 1155-1158. [3] Morgan, J.L. et al (2012) PNAS 109, 9989-9994. [4] Channon, M.B. et al (2015) Bone 77, 69-74. [5] Gordon, G.W. et al (2014) Leukemia 28, 2112-2115.
Weight loss and bone mineral density.
Hunter, Gary R; Plaisance, Eric P; Fisher, Gordon
2014-10-01
Despite evidence that energy deficit produces multiple physiological and metabolic benefits, clinicians are often reluctant to prescribe weight loss in older individuals or those with low bone mineral density (BMD), fearing BMD will be decreased. Confusion exists concerning the effects that weight loss has on bone health. Bone density is more closely associated with lean mass than total body mass and fat mass. Although rapid or large weight loss is often associated with loss of bone density, slower or smaller weight loss is much less apt to adversely affect BMD, especially when it is accompanied with high intensity resistance and/or impact loading training. Maintenance of calcium and vitamin D intake seems to positively affect BMD during weight loss. Although dual energy X-ray absorptiometry is normally used to evaluate bone density, it may overestimate BMD loss following massive weight loss. Volumetric quantitative computed tomography may be more accurate for tracking bone density changes following large weight loss. Moderate weight loss does not necessarily compromise bone health, especially when exercise training is involved. Training strategies that include heavy resistance training and high impact loading that occur with jump training may be especially productive in maintaining, or even increasing bone density with weight loss.
NASA Technical Reports Server (NTRS)
Spurrell, F. A.; Brenes, J.; Waibel, P.
1974-01-01
Roentgen signs, subperiosteal, endosteal, and trabecular bone growth are evaluated in turkeys fed phosphorus at the 0.5, 0.56, 0.68, 0.90, and 2.70 percent levels. Calcium levels of 0.30, 0.40, 0.60, 1.2, and 3.60 percent were also tested. Vitamin D levels of 0, 100, 300, 900 and 27,000 I.U. per day were likewise evaluated. Roentgen signs, bone mineral as measured by T-125 gamma ray absorption, and bone mineral growth patterns as shown by radiograph area projection are correlated with calcium, phosphorus, and vitamin D feeding levels. Differences in bone growth at the various feeding levels were observed which were not reflected by differences in other studied parameters.
Calcium oxalate contribution to calcium cycling in forests of contrasting nutrient status
Dauer, Jenny M.; Perakis, Steven S.
2014-01-01
Calcium oxalate (Ca oxalate) is an insoluble biomineral that forms in plants and fungi, and occurs in soils across many types of ecosystems. Assessing how Ca oxalate may shape ecosystem Ca cycling requires information on the distribution of Ca oxalate among plant biomass, detritus, and mineral soil, and how it varies with ecosystem Ca status. We compared two Douglas-fir forests of contrasting ecosystem Ca availability, and found that Ca oxalate was partitioned similarly among plant biomass, detritus and mineral soil major ecosystem compartments at both sites, and total pools of Ca oxalate were greater in the high-Ca forest. However, the proportional importance of Ca oxalate was greater in the low-Ca than high-Ca forest (18% versus 4% of actively cycling ecosystem Ca, respectively). And calcium oxalate in mineral soil, which is of particular interest as a potential long-term Ca reservoir, was a larger portion of total available Ca (exchangeable Ca plus Ca oxalate Ca) in the low-Ca site than the high-Ca site (9% versus 1% of available soil Ca, respectively). Calcium oxalate was the dominant form of Ca returned from plants to soil as leaf litterfall at the high-Ca site, yet calcium oxalate disappeared rapidly from decomposing litter (0.28 yr−1 or faster) at both sites. We conclude that accumulation of Ca oxalate in forest ecosystems appears most closely related to overall Ca supply for live biomass pools, and that the accumulation of Ca oxalate in forest floor and mineral soil is limited by rapid microbial degradation of putatively unavailable Ca oxalate.
Wollastonite : a versatile industrial mineral
,
2001-01-01
Wollastonite is a chemically simple mineral named in honor of English mineralogist and chemist Sir W.H. Wollaston (1766–1828). It is composed of calcium (Ca) and silicon and oxygen (SiO2, silica) with the chemical formula CaSiO3. Although much wollastonite is relatively pure CaSiO3, it can contain some iron, magnesium, manganese, aluminum, potassium, sodium, or strontium substituting for calcium in the mineral structure. Pure wollastonite is bright white; the type and amount of impurities can produce gray, cream, brown, palegreen, or red colors.
Effect of swimming on bone metabolism in adolescents.
Derman, Orhan; Cinemre, Alphan; Kanbur, Nuray; Doğan, Muhsin; Kiliç, Mustafa; Karaduman, Erdem
2008-01-01
Physical activity has been shown to have a positive effect on bone metabolism among adolescents. The objective of this study was to determine the effect of swimming on bone metabolism during adolescence. Swimming, as a non-weight-bearing sport, has been considered to be insignificant in the maintenance of bone mass. We studied whether swimming is associated with a higher peak bone mass. Forty swimmers (males aged 10-17 years and females aged 9-16 years) were studied. The control group consisted of the same number of adolescents aged between 10-16 years who did not swim; distribution of male and female gender was similar in the non-swimming control group compared to the swimming group. Adolescents were matched for age, gender and pubertal stages based on Tanner staging. All subjects underwent combined measurement of bone mineral metabolism by dual-energy X-ray absorptiometry of total body calcium content, and specific biochemical markers of turnover including osteocalcin, calcium, phosphorus and alkaline phosphatase. Bone age (determined by Greulich and Pyle's Radiographic Atlas of Skeletal Development of the Hand and Wrist), weight, height, ideal body weight, ideal body weight ratio, body mass index, Tanner classification (rated by examiner), diet, history of tobacco and alcohol exposure, exercise, socioeconomic status and history of chronic illness and medications were recorded to evaluate potential mediators that would affect bone metabolism. Tanner staging was used to assess puberty, and diet was evaluated based on reported consumption of milk, yogurt and cheese and cola/caffeine beverage consumption daily. There was significant difference in bone mineral content between adolescent male swimmers and the control group males. Consumption of cola beverages were significantly higher among the control group compared with the swimmer group. Ideal body weight ratio was significantly high among the female control group compared with female swimmers. Milk consumption was significantly higher for both male and female swimmer groups, whereas yogurt consumption was only significantly higher in the male swimmer group compared with control group. These results indicate that a highly active nonimpact sport such as swimming may lead to increased bone mineral content only for male swimmers. However, dietary behaviors may be more important than swimming on bone metabolism among adolescents.
Proper Calcium Use: Vitamin K2 as a Promoter of Bone and Cardiovascular Health.
Maresz, Katarzyna
2015-02-01
Inadequate calcium intake can lead to decreased bone mineral density, which can increase the risk of bone fractures. Supplemental calcium promotes bone mineral density and strength and can prevent osteoporosis. Recent scientific evidence, however, suggests that elevated consumption of calcium supplements may raise the risk for heart disease and can be connected with accelerated deposit of calcium in blood-vessel walls and soft tissues. In contrast, vitamin K2 is associated with the inhibition of arterial calcification and arterial stiffening. An adequate intake of vitamin K2 has been shown to lower the risk of vascular damage because it activates matrix GLA protein (MGP), which inhibits the deposits of calcium on the walls. Vitamin K, particularly as vitamin K2, is nearly nonexistent in junk food, with little being consumed even in a healthy Western diet. Vitamin K deficiency results in inadequate activation of MGP, which greatly impairs the process of calcium removal and increases the risk of calcification of the blood vessels. An increased intake of vitamin K2 could be a means of lowering calcium-associated health risks.
Gemede, Habtamu Fekadu; Haki, Gulelat Desse; Beyene, Fekadu; Woldegiorgis, Ashagrie Z; Rakshit, Sudip Kumar
2016-03-01
The promotion and consumption of indigenous vegetables could help to mitigate food insecurity and alleviate malnutrition in developing countries. Nutrient and antinutrient compositions of eight accessions of Okra Pods were investigated. Molar ratios and mineral bioavailability of Okra pod accessions were also calculated and compared to the critical values to predict the implications for mineral bioavailability. Proximate and mineral composition of Okra pod accessions were determined using standard methods of Association of Official Analytical Chemists. The result of the study revealed that the proximate composition (g/100 g) in dry weight basis was significantly (P < 0.05) varied and ranged: moisture/dry matter 9.69-13.33, crude protein 10.25-26.16, crude fat 0.56-2.49, crude fiber 11.97-29.93, crude ash 5.37-11.30, utilizable carbohydrate 36.66-50.97, and gross energy 197.26-245.55 kcal/100 g. The mineral concentrations (mg/100 g) were also significantly (P < 0.05) varied and ranged: calcium (111.11-311.95), Iron (18.30-36.68), potassium (122.59-318.20), zinc (3.83-6.31), phosphorus (25.62-59.72), and sodium (3.33-8.31) on dry weight bases. The Okra Pods of "OPA#6" accession contained significantly higher amounts of crude protein, total ash, crude fat, calcium, iron, and zinc than all other accessions evaluated in this study. The results of antinutrients analysis showed that, except phytate, tannin, and oxalate contents of all the accessions were significantly (P < 0.05) varied. The range of phytate, tannin, and oxalate contents (mg/100 g) for Okra pod accessions studied were as follows: 0.83-0.87, 4.93-9.90, and 0.04-0.53, respectively. The calculated molar ratios of phytate: calcium, phytate: iron, phytate: zinc, oxalate: calcium and [Phytate][Calcium]/[Zinc] were below the critical value and this indicate that the bioavailability of calcium, iron, and zinc in these accessions could be high. The results of the study revealed that Okra pod contain appreciable amount of vital nutrients like protein, fiber, calcium, iron, and zinc and low in antinutrient contents with high mineral bioavailability. Therefore, increase in the production and consumption of these nutrient-rich indigenous Okra pods will help to supplement/formulate the diets and alleviate the problems associated with malnutrition in the country.
Nguyen, Christelle; Bazin, Dominique; Daudon, Michel; Chatron-Colliet, Aurore; Hannouche, Didier; Bianchi, Arnaud; Côme, Dominique; So, Alexander; Busso, Nathalie; Busso, Nathalie; Lioté, Frédéric; Ea, Hang-Korng
2013-01-01
Calcium-containing (CaC) crystals, including basic calcium phosphate (BCP) and calcium pyrophosphate dihydrate (CPP), are associated with destructive forms of osteoarthritis (OA). We assessed their distribution and biochemical and morphologic features in human knee OA cartilage. We prospectively included 20 patients who underwent total knee replacement (TKR) for primary OA. CaC crystal characterization and identification involved Fourier-transform infra-red spectrometry and scanning electron microscopy of 8 to 10 cartilage zones of each knee, including medial and lateral femoral condyles and tibial plateaux and the intercondyle zone. Differential expression of genes involved in the mineralization process between cartilage with and without calcification was assessed in samples from 8 different patients by RT-PCR. Immunohistochemistry and histology studies were performed in 6 different patients. Mean (SEM) age and body mass index of patients at the time of TKR was 74.6 (1.7) years and 28.1 (1.6) kg/m², respectively. Preoperative X-rays showed joint calcifications (chondrocalcinosis) in 4 cases only. The medial femoro-tibial compartment was the most severely affected in all cases, and mean (SEM) Kellgren-Lawrence score was 3.8 (0.1). All 20 OA cartilages showed CaC crystals. The mineral content represented 7.7% (8.1%) of the cartilage weight. All patients showed BCP crystals, which were associated with CPP crystals for 8 joints. CaC crystals were present in all knee joint compartments and in a mean of 4.6 (1.7) of the 8 studied areas. Crystal content was similar between superficial and deep layers and between medial and femoral compartments. BCP samples showed spherical structures, typical of biological apatite, and CPP samples showed rod-shaped or cubic structures. The expression of several genes involved in mineralization, including human homolog of progressive ankylosis, plasma-cell-membrane glycoprotein 1 and tissue-nonspecific alkaline phosphatase, was upregulated in OA chondrocytes isolated from CaC crystal-containing cartilages. CaC crystal deposition is a widespread phenomenon in human OA articular cartilage involving the entire knee cartilage including macroscopically normal and less weight-bearing zones. Cartilage calcification is associated with altered expression of genes involved in the mineralisation process.
Effects of Eggshell Calcium Supplementation on Bone Mass in Postmenopausal Vietnamese Women.
Sakai, Seigo; Hien, Vu Thi Thu; Tuyen, Le Danh; Duc, Ha Anh; Masuda, Yasunobu; Yamamoto, Shigeru
2017-01-01
Bone mass decreases along with aging, especially for women after menopause because of lower estrogen secretion together with low calcium intake. This study was conducted to study the effect of eggshell calcium supplementation on bone mass in 54 postmenopausal Vietnamese women living in a farming area about 60 km from Hanoi, Vietnam. Sets of 3 subjects matched by age, bone mass, BMI and calcium intake were divided randomly into 3 groups with 18 subjects in each group. The eggshell calcium group was administered 300 mg/d calcium from eggshell, the calcium carbonate group 300 mg/d calcium from calcium carbonate and the placebo group received no calcium supplementation. Bone mass (Speed of Sound (SOS)) was measured at the beginning (the baseline), the middle (6th month) and the end of the study (12th month) by the single blind method. SOS of the eggshell group increased significantly at 12 mo (p<0.05) and was significantly higher than that of the placebo and calcium carbonate groups at 12 mo (p<0.05). The SOS of the calcium carbonate group tended to be higher than that of the placebo group but without a significant difference (p>0.05). In conclusion, eggshell calcium was more effective in increasing bone mass than calcium carbonate in postmenopausal Vietnamese women.
Dentin-cement Interfacial Interaction
Atmeh, A.R.; Chong, E.Z.; Richard, G.; Festy, F.; Watson, T.F.
2012-01-01
The interfacial properties of a new calcium-silicate-based coronal restorative material (Biodentine™) and a glass-ionomer cement (GIC) with dentin have been studied by confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), micro-Raman spectroscopy, and two-photon auto-fluorescence and second-harmonic-generation (SHG) imaging. Results indicate the formation of tag-like structures alongside an interfacial layer called the “mineral infiltration zone”, where the alkaline caustic effect of the calcium silicate cement’s hydration products degrades the collagenous component of the interfacial dentin. This degradation leads to the formation of a porous structure which facilitates the permeation of high concentrations of Ca2+, OH-, and CO32- ions, leading to increased mineralization in this region. Comparison of the dentin-restorative interfaces shows that there is a dentin-mineral infiltration with the Biodentine, whereas polyacrylic and tartaric acids and their salts characterize the penetration of the GIC. A new type of interfacial interaction, “the mineral infiltration zone”, is suggested for these calcium-silicate-based cements. PMID:22436906
Calcium, magnesium, and phosphate abnormalities in the emergency department.
Chang, Wan-Tsu W; Radin, Bethany; McCurdy, Michael T
2014-05-01
Derangements of calcium, magnesium, and phosphate are associated with increased morbidity and mortality. These minerals have vital roles in the cellular physiology of the neuromuscular and cardiovascular systems. This article describes the pathophysiology of these mineral disorders. It aims to provide the emergency practitioner with an overview of the diagnosis and management of these disorders. Copyright © 2014 Elsevier Inc. All rights reserved.
Al-Farsi, Yahya M; Waly, Mostafa I; Al-Sharbati, Marwan M; Al-Shafaee, Mohammed A; Al-Farsi, Omar A; Al-Khaduri, Maha M; Gupta, Ishita; Ouhtit, Allal; Al-Adawi, Samir; Al-Said, Mona F; Deth, Richard C
2013-02-01
Toxic levels of heavy metals and low levels of essential minerals have been suggested to play a critical role in the pathogenesis of autism spectrum disorders (ASD). This study documents the levels of heavy metals and essential minerals in hair samples of children with ASD in Muscat, the urbanized capital of Oman, Muscat. The study included 27 children with ASD and 27 matched non-ASD controls. Parental interviews were held and dietary intake questionnaires completed in conjunction with the collection of hair samples. Analysis of heavy metals and essential minerals was carried out by inductively coupled plasma mass spectrometry. Chi-square analysis and non-parametric Fisher's exact tests were used to assess statistical significance. Children with ASD had significantly higher levels of all 11 analyzed heavy metals in their hair samples (P < 0.05), ranging from 150 to 365 % of control levels. ASD children also had significantly higher levels of essential minerals sulfur, sodium, magnesium, potassium, zinc, and iron, but lower levels of calcium and copper in their hair samples. This study corroborates data from previous studies in different parts of the world indicating the presence of elevated levels of heavy metals and selective depletion of essential minerals in the hair of children with ASD.
Olmedo, Hidekel; Herrera, María; Rojas, Leonardo; Villalta, Mauren; Vargas, Mariángela; Leiguez, Elbio; Teixeira, Catarina; Estrada, Ricardo; Gutiérrez, José María; León, Guillermo; Montero, Mavis L
2014-01-01
The adjuvanticity of aluminum hydroxide and calcium phosphate on the antibody response in mice towards the venom of the snake Bothrops asper was studied. It was found that, in vitro, most of the venom proteins are similarly adsorbed by both mineral salts, with the exception of some basic phospholipases A2, which are better adsorbed by calcium phosphate. After injection, the adjuvants promoted a slow release of the venom, as judged by the lack of acute toxicity when lethal doses of venom were administered to mice. Leukocyte recruitment induced by the venom was enhanced when it was adsorbed on both mineral salts; however, venom adsorbed on calcium phosphate induced a higher antibody response towards all tested HPLC fractions of the venom. On the other hand, co-precipitation of venom with calcium phosphate was the best strategy for increasing: (1) the capacity of the salt to couple venom proteins in vitro; (2) the venom ability to induce leukocyte recruitment; (3) phagocytosis by macrophages; and (4) a host antibody response. These findings suggest that the chemical nature is not the only one determining factor of the adjuvant activity of mineral salts.
Pacheco, Anália Lúcia Vieira; Pagliarini, Mateus Francisco; de Freitas, Gilberto Bernardo; Santos, Ricardo Henrique Silva; Serrão, José Eduardo; Zanuncio, José Cola
2017-02-15
The use of organic foods has been increased in the world. Organic fertilizers, like cattle manure, have emerged as an important component of the organic system production. The production, mass, size, and mineral composition of passion fruit pulp were evaluated when treated with a mineral fertilizer (control) (MIN) or cattle manure at a single dose equivalent to potassium fertilizer (ORG) or double dose (2×ORG). The production and the numbers of fruits of plants treated with MIN and 2×ORG was higher than with ORG. The level of nitrogen (N), phosphorus (P), zinc (Zn), iron (Fe), and copper (Cu) in the fruit pulp was similar with all three fertilizers, but the calcium (Ca) and magnesium (Mg) was higher with ORG and 2×ORG. The number and weight of the fruits of passion fruit treated with 2×ORG were similar to those with MIN fertilizer, but they contained more Ca and Mg. Copyright © 2016 Elsevier Ltd. All rights reserved.
Dahl, Cecilie; Søgaard, Anne Johanne; Tell, Grethe S; Forsén, Lisa; Flaten, Trond Peder; Hongve, Dag; Omsland, Tone Kristin; Holvik, Kristin; Meyer, Haakon E; Aamodt, Geir
2015-12-01
The Norwegian population has among the highest hip fracture rates in the world. The incidence varies geographically, also within Norway. Calcium in drinking water has been found to be beneficially associated with bone health in some studies, but not in all. In most previous studies, other minerals in water have not been taken into account. Trace minerals, for which drinking water can be an important source and even fulfill the daily nutritional requirement, could act as effect-modifiers in the association between calcium and hip fracture risk. The aim of the present study was to investigate the association between calcium in drinking water and hip fracture, and whether other water minerals modified this association. A survey of trace metals in 429 waterworks, supplying 64% of the population in Norway, was linked geographically to the home addresses of patients with incident hip fractures (1994-2000). Drinking water mineral concentrations were divided into "low" (below and equal waterworks average) and "high" (above waterworks average). Poisson regression models were fitted, and all incidence rate ratios (IRRs) were adjusted for age, geographic region, urbanization degree, type of water source, and pH of the water. Effect modifications were examined by stratification, and interactions between calcium and magnesium, copper, zinc, iron and manganese were tested both on the multiplicative and the additive scale. Analyses were stratified on gender. Among those supplied from the 429 waterworks (2,110,916 person-years in men and 2,397,217 person-years in women), 5433 men and 13,493 women aged 50-85 years suffered a hip fracture during 1994-2000. Compared to low calcium in drinking water, a high level was associated with a 15% lower hip fracture risk in men (IRR=0.85, 95% CI: 0.78, 0.91) but no significant difference was found in women (IRR=0.98, 95%CI: 0.93-1.02). There was interaction between calcium and copper on hip fracture risk in men (p=0.051); the association between calcium and hip fracture risk was stronger when the copper concentration in water was high (IRR=0.52, 95% CI: 0.35, 0.78) as opposed to when it was low (IRR=0.88, 95% CI: 0.81, 0.94). This pattern persisted also after including potential confounding factors and other minerals in the model. No similar variation in risk was found in women. In this large, prospective population study covering two thirds of the Norwegian population and comprising 19,000 hip fractures, we found an inverse association between calcium in drinking water and hip fracture risk in men. The association was stronger when the copper concentration in the water was high. Copyright © 2015 Elsevier Inc. All rights reserved.
Jackson, Robert T.; Alkahtani, Abdulkareem A.
2018-01-01
Background Saudi women depend on food sources to maintain their serum 25(OH) D concentrations because covering by traditional clothing and time spent indoors limit their sun exposure. Little is known about vitamin D intake and its main food sources in Saudi Arabia. In addition, the association between vitamin D and calcium intake and bone mineral density (BMD) in young women is not well researched. Objectives To assess the adequacy of vitamin D intake among Saudi women as compared to the estimated average requirements (EARs), to identify dietary vitamin D sources, to examine potential determinants of vitamin D intake, and to assess bone health and the association of calcium and vitamin D intake with BMD. Methods This cross-sectional study was conducted in 257 premenopausal women aged 20–50 years in Jeddah, Saudi Arabia. Dietary vitamin D and calcium were assessed by the Semiquantitative Food Frequency Questionnaire. BMD was measured using dual-energy X-ray absorptiometry (DXA) in a subset of women (n=102) at the lumbar spine and femur neck. Results Sixty-five percent of women were below the EAR for vitamin D, and 61% fell below the EAR for calcium. Dairy products, supplements, and fish contributed most to vitamin D intake. Increased age was an independent determinant of sufficient vitamin D intake (p < 0.001). The prevalence of osteopenia was 33% in the lumbar spine and 30% in the femur neck. There was a significant positive association between calcium intake and BMD at the lumbar spine (p=0.043) after controlling for body mass index and energy intake. Vitamin D intake was not significantly different between women with low and normal bone mass. Conclusion Premenopausal women in Jeddah have insufficient vitamin D and calcium intakes. Public health strategies to improve nutrition in young women are needed, and expanding fortification programs to include all dairy products would be useful. PMID:29750126
TRANSIENT AMORPHOUS CALCIUM PHOSPHATE IN FORMING ENAMEL
Beniash, Elia; Metzler, Rebecca A.; Lam, Raymond S.K.; Gilbert, P.U.P.A.
2009-01-01
Enamel, the hardest tissue in the body, begins as a three-dimensional network of nanometer size mineral particles, suspended in a protein gel. This mineral network serves as a template for mature enamel formation. To further understand the mechanisms of enamel formation we characterized the forming enamel mineral at an early secretory stage using x-ray absorption near-edge structure (XANES) spectromicroscopy, transmission electron microscopy (TEM), FTIR microspectroscopy and polarized light microscopy. We show that the newly formed enamel mineral is amorphous calcium phosphate (ACP), which eventually transforms into apatitic crystals. Interestingly, the size, shape and spatial organization of these amorphous mineral particles and older crystals are essentially the same, indicating that the mineral morphology and organization in enamel is determined prior to its crystallization. Mineralization via transient amorphous phases has been previously reported in chiton teeth, mollusk shells, echinoderm spicules and spines, and recent reports strongly suggest the presence transient amorphous mineral in forming vertebrate bones. The present finding of transient ACP in murine tooth enamel suggests that this strategy might be universal. PMID:19217943
Development of calcium bodies in Hylonsicus riparius (Crustacea: Isopoda).
Vittori, Miloš; Khurshed, Mohammed; Picavet, Daisy I; van Noorden, Cornelis J F; Štrus, Jasna
2018-03-01
Calcium bodies are internal epithelial sacs found in terrestrial isopods of the family Trichoniscidae that contain a mineralized extracellular matrix that is deposited and resorbed in relation to the molt cycle. Calcium bodies in several trichoniscids are filled with bacteria, the function of which is currently unknown. The woodlouse Hyloniscus riparius differs from other trichoniscids in that it possesses two different pairs of calcium bodies, the posterior pair being filled with bacteria and the anterior pair being devoid of bacteria. We explored the development of these organs and bacterial colonization of their lumen during the postmarsupial development with the use of optical clearing and whole-body confocal imaging of larval and juvenile stages. Our results show that calcium bodies are formed as invaginations of the epidermis in the region of intersegmental membranes during the postmarsupial development. The anterior pair of calcium bodies is generated during the first postmarsupial manca stage, whereas the posterior calcium bodies first appear in juveniles and are immediately colonized by bacteria, likely through a connection between the calcium body lumen and the body surface. Mineral is deposited in calcium bodies as soon as they are present. Copyright © 2018 Elsevier Ltd. All rights reserved.
Ovariectomy-induced changes in aged beagles: Histomorphometry and mineral content of the rib
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, A.K.; Bhattacharyya, M.H.; Hurst, D.
1997-08-01
The effects of ovariectomy on the aged beagle skeleton were studied by histomorphometric analysis of the cortical bone in sequential rib biopsies. Biopsies were taken from each ovariectomized (OV) or sham-operated (SO) dog at the time of surgery and at 1, 4, and 8.5 months after surgery. Tetracycline, calcein, and xylenol orange, respectively, were administered by a fluorochrome labeling procedure (2d-10d-2d) just prior to each postoperative biopsy to provide markers of bone formation. Analysis of sequential biopsies provided a means to follow the response to ovariectomy over time and compare each animal against its own baseline. Examination of sequential biopsiesmore » indicated that cortical porosity increased by the fourth month after ovariectomy and remained high at 8.5 months. Ovariectomy did not influence histomorphometric indices at one month after surgery, but substantial differences were observed at later times. Ovariectomy stimulated a transient increase in bone formation and was increased six-fold over that of SO dogs at four months. Ribs were also analyzed for mineral content at necropsy. The rib was heterogeneous along its length for calcium content and concentration. In the midrib where biopsies for histomorphometric analysis were taken, ovariectomy induced a decrease in mass and mineral content; total calcium was decreased by approximately 31%. These data demonstrate that the rib cortical bone is a responsive site for the effects of ovariectomy in female dogs.« less
Osteoporosis: Are we measuring what we intend to measure? In search of the ideal bone strength study
NASA Astrophysics Data System (ADS)
de Riese, Cornelia
2006-02-01
In 1991 the World Health Organization (WHO) defined osteoporosis as a "loss of bone mass and micro architectural deterioration of the skeleton leading to increased risk of fracture." 1,2 Since microarchitecture can not be measured directly, a panel of the WHO recommended that the diagnosis be made according to a quantifiable surrogate marker, calcium mineral, in bone. Subsequently in 1994, the definition focused on the actual bone "density," giving densitometric technology a central place in establishing the diagnosis of osteoporosis. 3,4 But soon it became obvious that there was only limited correlation between bone mineral density (BMD) and actual occurrence of fractures and that decreases in bone mass account for only about 50% of the deterioration of bone strength with aging. In other words only about 60% of bone strength is related to BMD. 5 Recent developments in bone research have shown that bone mineral density in itself is not sufficient to accurately predict fracture risk. Bone is composed of inorganic calcium apatite crystals that mineralize an organic type I collagen matrix. The degree of mineralization, the properties of the collagen matrix, crystal size, trabecular orientation, special distribution of the different components and many more factors are all impacting bone strength. 6-14 Human cadaver studies have confirmed the correlation between bone density and bone. 26 strength. 5,15-20 Changes in cancellous bone morphology appear to lead to a disproportionate decrease in bone strength. 21-26 When postmenopausal women are stratified by age, obvious differences between BMD and actual fracture risk are observed. 24 Felsenberg eloquently summarizes what he calls the "Bone Quality Framework." In great detail he talks about the geometry and micro- architecture of bone and how the different components are related to functional stability. 27 Are our current testing modalities appropriately addressing these structural factors? Are we keeping in mind that in screening for osteoporosis the key variable is fragility, not bone density itself? All currently FDA approved and commercially available equipments for the evaluation of bone status claim that they - at least indirectly - assess the biological fracture risk. This review summarizes an extensive current literature research covering FDA approved as well as experimental devices for the evaluation of bone. The pros and cons of the different techniques are discussed in the context of diagnostic accuracies and practical implications.
Hernández-Becerra, Ezequiel; Gutiérrez-Cortez, Elsa; Del Real, Alicia; Rojas-Molina, Alejandra; Rodríguez-García, Mario; Rubio, Efraín; Quintero-García, Michelle; Rojas-Molina, Isela
2017-02-04
Mechanical, microstructural properties, mineral content and bone mineral density (BMD) of the femur were evaluated in growing rats fed with Opuntia ficus indica (L.) Mill. (Cactaceae) cladodes at different maturity stages as calcium source. Male weanling rats were fed with cladodes at early maturity stage (25 and 60 days of age, belonging to groups N-60 and N-200, respectively) and cladodes at late maturity stage (100 and 135 days of age, belonging to groups N-400 and N-600, respectively) for 6 weeks. Additionally, a control group fed with calcium carbonate as calcium source was included for comparative purposes. All diets were fitted to the same calcium content (5 g/kg diet). The failure load of femurs was significantly lower ( p ≤ 0.05) in groups N-60 and N-200 in comparison to N-400, N-600 and control groups. The cortical width (Ct.Wi) and trabecular thickness (Tb.Th) of the femurs in control and N-600 groups were significantly higher ( p ≤ 0.05) than Ct.Wi and Tb.Th of femurs in groups N-60 and N-200. Trabecular separation of the femurs in N-60 and N-200 groups showed the highest values compared with all experimental groups. The highest calcium content in the femurs were observed in control, N-600 and N-400 groups; whereas the lowest phosphorus content in the bones were detected in N-200, N-600 and N-400 groups. Finally, the BMD in all experimental groups increased with age; nevertheless, the highest values were observed in N-600 and control groups during pubertal and adolescence stages. The results derived from this research demonstrate, for the first time, that the calcium found in Opuntia ficus indica cladodes is actually bioavailable and capable of improving mineral density and mechanical and microstructural properties of the bones. These findings suggest that the consumption of cladodes at late maturity stage within the diet might have a beneficial impact on bone health.
Hernández-Becerra, Ezequiel; Gutiérrez-Cortez, Elsa; Del Real, Alicia; Rojas-Molina, Alejandra; Rodríguez-García, Mario; Rubio, Efraín; Quintero-García, Michelle; Rojas-Molina, Isela
2017-01-01
Mechanical, microstructural properties, mineral content and bone mineral density (BMD) of the femur were evaluated in growing rats fed with Opuntia ficus indica (L.) Mill. (Cactaceae) cladodes at different maturity stages as calcium source. Male weanling rats were fed with cladodes at early maturity stage (25 and 60 days of age, belonging to groups N-60 and N-200, respectively) and cladodes at late maturity stage (100 and 135 days of age, belonging to groups N-400 and N-600, respectively) for 6 weeks. Additionally, a control group fed with calcium carbonate as calcium source was included for comparative purposes. All diets were fitted to the same calcium content (5 g/kg diet). The failure load of femurs was significantly lower (p ≤ 0.05) in groups N-60 and N-200 in comparison to N-400, N-600 and control groups. The cortical width (Ct.Wi) and trabecular thickness (Tb.Th) of the femurs in control and N-600 groups were significantly higher (p ≤ 0.05) than Ct.Wi and Tb.Th of femurs in groups N-60 and N-200. Trabecular separation of the femurs in N-60 and N-200 groups showed the highest values compared with all experimental groups. The highest calcium content in the femurs were observed in control, N-600 and N-400 groups; whereas the lowest phosphorus content in the bones were detected in N-200, N-600 and N-400 groups. Finally, the BMD in all experimental groups increased with age; nevertheless, the highest values were observed in N-600 and control groups during pubertal and adolescence stages. The results derived from this research demonstrate, for the first time, that the calcium found in Opuntia ficus indica cladodes is actually bioavailable and capable of improving mineral density and mechanical and microstructural properties of the bones. These findings suggest that the consumption of cladodes at late maturity stage within the diet might have a beneficial impact on bone health. PMID:28165410
NASA Astrophysics Data System (ADS)
Chen, Cen; Kong, Xiangdong; Zhang, Sheng-Min; Lee, In-Seop
2015-04-01
Nanocomposite layers of mineral/osteogenic growth peptide (OGP) were synthesized on calcium phosphate coated titanium substrates by immersing in calcium-phosphate buffer solution containing OGP. Peptide incorporated mineral was characterized by determining quantity loaded, effects on mineral morphology and structure. Also, the biological activity was investigated by cell adhesion, proliferation assay, and measurement of alkaline phosphatase (ALP) activity. X-ray photoelectron spectroscopy (XPS) and micro-bicinchoninic acid (BCA) assay revealed that OGP was successfully incorporated with mineral and the amount was increased with immersion time. Incorporated OGP changed the mineral morphology from sharp plate-like shape to more rounded one, and the octacalcium phosphate structure of the mineral was gradually transformed into apatite. With confocal microscopy to examine the incorporation of fluorescently labeled peptide, OGP was evenly distributed throughout mineral layers. Mineral/OGP nanocomposites promoted cell adhesion and proliferation, and also increased ALP activity of mesenchymal stem cells (MSCs). Results presented here indicated that the mineral/OGP nanocomposites formed on titanium substrates had the potential for applications in dental implants.
NASA Astrophysics Data System (ADS)
Burgos-Cara, Alejandro; Ruiz-Agudo, Encarnacion; Putnis, Christine V.
2016-04-01
Calcium oxalate (CaC2O4ṡxH2O) minerals are naturally occurring minerals found in fossils, plants, kidney stones and is a by-product in some processes such as paper, food and beverage production [1,2]. In particular, calcium oxalate monohydrate phase (COM) also known as whewellite (CaC2O4ṡH2O), is the most frequently reported mineral phase found in urinary and kidney stones together with phosphates. Organic additives are well known to play a key role in the formation of minerals in both biotic and abiotic systems, either facilitating their precipitation or hindering it. In this regard, recent studies have provided direct evidence demonstrating that citrate species could enhance dissolution of COM and inhibit their precipitation. [3,4] The present work aims at evauate the influence of pH, citrate and oxalic acid concentrations in calcium oxalate precipitation on calcite surfaces (Island Spar, Chihuahua, Mexico) through in-situ nanoscale observation using in situ atomic force microscopy (AFM, Multimode, Bruker) in flow-through experiments. Changes in calcium oxalate morphologies and precipitated phases were observed, as well as the inhibitory effect of citrate on calcium oxalate precipitation, which also lead to stabilization an the amorphous calcium oxalate phase. [1] K.D. Demadis, M. Öner, Inhibitory effects of "green"additives on the crystal growth of sparingly soluble salts, in: J.T. Pearlman (Ed.), Green Chemistry Research Trends, Nova Science Publishers Inc., New York, 2009, pp. 265-287. [2] M. Masár, M. Zuborová, D. Kaniansky, B. Stanislawski, Determination of oxalate in beer by zone electrophoresis on a chip with conductivity detection, J. Sep. Sci. 26 (2003) 647-652. [3] Chutipongtanate S, Chaiyarit S, Thongboonkerd V. Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells. Eur J Pharmacol 2012;689:219-25. [4] Weaver ML, Qiu SR, Hoyer JR, Casey WH, Nancollas GH, De Yoreo JJ. Inhibition of calcium oxalate monohydrate growth by citrate and the effect of the background electrolyte. J Cryst Growth 2007;306:135-45.
Fatty acid profile in patients with phenylketonuria and its relationship with bone mineral density.
Lage, Sergio; Bueno, María; Andrade, Fernando; Prieto, José Angel; Delgado, Carmen; Legarda, María; Sanjurjo, Pablo; Aldámiz-Echevarría, Luis Jose
2010-12-01
Patients with phenylketonuria (PKU) undergo a restrictive vegan-like diet, with almost total absence of n-3 fatty acids, which have been proposed as potential contributors to bone formation in the healthy population. The PKU diet might lead these patients to bone mass loss and, consequently, to the development of osteopenia/osteoporosis. Therefore, we proposed to analyze their plasma fatty acid profile status and its relationship with bone health. We recruited 47 PKU patients for this cross-sectional study and divided the cohort into three age groups (6-10 years, 11-18 years, 19-42 years). We measured their plasma fatty acid profile and bone mineral density (BMD) (both at the femoral neck and the lumbar spine). Seventy-seven healthy controls also participated as reference values of plasma fatty acids. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) and total n-3 fatty acids were significantly diminished in PKU patients compared with healthy controls. DHA, EPA, and total n-3 fatty acids were also positively associated with bone mineral density (r = 0.83, p = 0.010; r = 0.57, p = 0.006; r = 0.73, p = 0.040, respectively). There was no association between phenylalanine (Phe), Index of Dietary Control (IDC), calcium, 25-hydroxivitamin D concentrations, daily calcium intake, and BMD. Our results suggest a possible influence of essential fatty acids over BMD in PKU patients. The lack of essential n-3 fatty acids intake in the PKU diet might affect bone mineralization. Further clinical trials are needed to confirm the effect of the n-3 essential fatty acids on bone accrual in a cohort of PKU patients.
Pseudowollastonite Carbonation Could Enable New Frontiers in Carbon Storage
NASA Astrophysics Data System (ADS)
Plattenberger, D.; Tao, Z.; Ling, F. T.; Peters, C. A.; Clarens, A. F.
2017-12-01
One of the primary challenges of CO2 mineral trapping is that precipitation reactions are reversible. A wide range of solid magnesium, iron, or calcium carbonates (such as magnesite, MgCO3) can be synthesized by reacting mineral silicates (such as olivine, Mg2SiO4) with CO2 to produce mineral carbonates. However, if CO2 remains present at high concentrations, as would be the case in many subsurface environments, the carbonate minerals could re-dissolve, making the precipitated carbonates impermanent forms of storage. In this work, we study pseudowollastonite (CaSiO3), a crystalline form of calcium silicate that is common in slags, cement, and calcium-rich volcanic formations, for its potential to produce other secondary mineral phases that may be resistant to dissolution under low pH conditions. These secondary mineral precipitation phases have morphologies and X-ray diffraction patterns that resemble both calcium silicate hydrate gels as well as crystalline calcium silicate carbonate hydrates. The combination of these phases forms a complex system that may resist acid attack while providing strength and limiting flow in the subsurface environment. High pressure and temperature column experiments carried out in our lab show that pseudowollastonite carbonation effectively lowers permeability in columns of sintered glass beads. Many of the pore throats are clogged by precipitates, as seen using micro X-ray tomography of intact columns and electron microscopy of thin sections. The spatial distribution of the products suggests that calcite forms toward the inlet of the columns where the pCO2 is highest. This forms a barrier that reduces, but does not eliminate, the availability of CO2 deeper in the porous media where the secondary phases precipitate. The existence of the calcite zone drives the reduction in permeability and the depth of this zone is self-limiting, which could have important implications for limiting leakage and unwanted migration of CO2 in some instances.
Veganism and osteoporosis: a review of the current literature.
Smith, Annabelle M
2006-10-01
The purpose of this review is to examine the current literature regarding calcium and Vitamin D deficiencies in vegan diets and the possible relationship to low bone mineral density and incidence for fracture. Prominent databases were searched for original research publications providing data capable of answering these questions: (i) Do vegans have lower-than-recommended levels of calcium/Vitamin D? (ii) Do vegans have lower bone mineral density than their non-vegan counterparts? (iii) Are vegans at a greater risk for fractures than non-vegans? The findings gathered consistently support the hypothesis that vegans do have lower bone mineral density than their non-vegan counterparts. However, the evidence regarding calcium, Vitamin D and fracture incidence is inconclusive. More research is needed to definitively answer these questions and to address the effects of such deficiencies on the medical and socioeconomic aspects of life.
Unexpected link between polyketide synthase and calcium carbonate biomineralization.
Hojo, Motoki; Omi, Ai; Hamanaka, Gen; Shindo, Kazutoshi; Shimada, Atsuko; Kondo, Mariko; Narita, Takanori; Kiyomoto, Masato; Katsuyama, Yohei; Ohnishi, Yasuo; Irie, Naoki; Takeda, Hiroyuki
2015-01-01
Calcium carbonate biominerals participate in diverse physiological functions. Despite intensive studies, little is known about how mineralization is initiated in organisms. We analyzed the medaka spontaneous mutant, ha, defective in otolith (calcareous ear stone) formation. ha lacks a trigger for otolith mineralization, and the causative gene was found to encode polyketide synthase (pks), a multifunctional enzyme mainly found in bacteria, fungi, and plant. Subsequent experiments demonstrate that the products of medaka PKS, most likely polyketides or their derivatives, act as nucleation facilitators in otolith mineralization. The generality of this novel PKS function is supported by the essential role of echinoderm PKS in calcareous skeleton formation together with the presence of PKSs in a much wider range of animals from coral to vertebrates. The present study first links PKS to biomineralization and provides a genetic cue for biogeochemistry of carbon and calcium cycles.
Jia, Ting; Gama Axelsson, Thiane; Heimbürger, Olof; Bárány, Peter; Stenvinkel, Peter; Qureshi, Abdul Rashid
2014-01-01
Summary Background and objectives IGF-1 deficiency links to malnutrition in CKD patients; however, it is not clear to what extent it associates with survival among these patients. Design, setting, participants, & measurements Serum IGF-1 and other biochemical, clinical (subjective global assessment), and densitometric (dual energy x-ray absorptiometry) markers of nutritional status and mineral and bone metabolism were measured in a cohort of 365 Swedish clinically stable CKD stage 5 patients (median age of 53 years) initiating dialysis between 1994 and 2009; in 207 patients, measurements were also taken after 1 year of dialysis. Deaths were registered during a median follow-up of 5 years. Associations of mortality with baseline IGF-1 and changes of IGF-1 after 1 year of dialysis were evaluated by Cox models. Results At baseline, IGF-1 concentrations associated negatively with age, diabetes mellitus, cardiovascular disease, poor nutritional status, IL-6, and osteoprotegerin and positively with body fat mass, bone mineral density, serum phosphate, calcium, and fibroblast growth factor-23. At 1 year, IGF-1 had increased by 33%. In multivariate regression, low age, diabetes mellitus, and high serum phosphate and calcium associated with IGF-1 at baseline, and in a mixed model, these factors, together with high fat body mass, associated with changes of IGF-1 during the first 1 year of dialysis. Adjusting for calendar year of inclusion, age, sex, diabetes mellitus, cardiovascular disease, IL-6, and poor nutritional status, a 1 SD higher level of IGF-1 at baseline associated with lower mortality risk (hazard ratio, 0.57; 95% confidence interval, 0.32 to 0.98). Persistently low or decreasing IGF-1 levels during the first 1 year on dialysis predicted worse survival (adjusted hazard ratio, 2.19; 95% confidence interval, 1.06 to 4.50). Conclusion In incident dialysis patients, low serum IGF-1 associates with body composition and markers of mineral and bone metabolism, and it predicts increased mortality risk. PMID:24178975
Breast Microcalcification Detection Using Super-Resolution Ultrasound Image Reconstruction
2010-09-01
microcalcifications often occur as one of two types: calcium oxalate dihydrate or calcium hydroxyapatite. Their sizes range approximately from 0.1 mm to 0.5 mm...super-resolution imaging, ultrasound imaging, wave equation. 1. INTRODUCTION Microcalcifications, tiny specks of mineral deposits ( calcium ), are the
Scialla, Julia J
2018-07-01
Treatment of mineral metabolism is a mainstay of dialysis care including some of its most widely used and costly pharmaceuticals. Although many mineral metabolites are associated with increased risk of mortality, cardiovascular disease, and other morbidities, few clinical trials are available to guide therapy and most focus on single drug approaches. In practice, providers manage many aspects of mineral metabolism simultaneously in integrated treatment approaches that incorporate multiple agents and changes in the dialysis prescription. The present review discusses the rationale and existing evidence for evaluating integrated, as opposed to single drug, approaches in mineral metabolism. Drugs used to treat mineral metabolism have numerous, and sometimes, opposing effects on biochemical risk factors, such as fibroblast growth factor 23 (FGF23), calcium, and phosphorus. Although vitamin D sterols raise these risk markers when lowering parathyroid hormone (PTH), calcimimetics lower them. Trials demonstrate that combined approaches best 'normalize' the mineral metabolism axis in end-stage renal disease (ESRD). Observations embedded within major trials of calcimimetics reveal that adjustment of calcium-based binders and dialysate calcium is a common approach to adverse effects of these drugs with some initial, but inconclusive, evidence that these co-interventions may impact outcomes. The multiple, and often opposing, biochemical effects of many mineral metabolism drugs provides a strong rationale for studying integrated management strategies that consider combinations of drugs and co-interventions as a whole. This remains a current gap in the field with opportunities for clinical trials.
Use of ossein-hydroxyapatite complex in the prevention of bone loss: a review.
Castelo-Branco, C; Dávila Guardia, J
2015-02-01
The ossein-hydroxyapatite complex (OHC) is a microcrystalline form of calcium which provides a number of additional minerals (magnesium, phosphorus, potassium, zinc), and proteins (osteocalcin, type I collagen, type I insulin growth factor I and II, transforming growth factor beta) associated with bone metabolism. The objective of this review is to examine the role of OHC in preventing bone loss in different conditions. A review of clinical trials assessing the relationship between OHC and bone loss was made using the following data sources: Medline (from 1966 to December 2013), the Cochrane Controlled Clinical Trials Register, Embase (up to December 2013), contact with companies marketing the supplements studied, and reference lists. Different randomized, clinical trials and meta-analysis suggest that OHC is more effective than calcium supplements in maintaining bone mass in postmenopausal women and in different conditions related to bone loss. In addition, OHC improves pain symptoms and accelerates fracture consolidation in patients with osteopenia or osteoporosis. The ossein-hydroxyapatite complex is significantly more effective in preventing bone loss than calcium carbonate.
NASA Technical Reports Server (NTRS)
Morukov, B. V.; Zaychik, V. YE.; Ivanov, V. M.; Orlov, O. I.
1988-01-01
Compounds of the diphosphonate group suppress bone resorption and bone tissue metabolism, from which it was assumed that they can be used for the prevention of osteoporosis and disorders of calcium homeostasis in humans during space flight. Two compounds of this group were used for preventive purposes in 60 day hypokinesia in rats. The results showed that diphosphonates have a marked effect on calcium metabolism and the condition of the bone tissues under conditions of long term hypokinesia: they reduce the content of ionized calcium in blood, delay the loss of calcium and phosphorus by the bone tissue, and to a considerable degree prevent reduction of bone density. This confirms the possibility of using compounds of this group for correcting and preventing changes of bone tissue and mineral metabolism during long term hypokinesia.
Fenton, Tanis R; Eliasziw, Misha; Tough, Suzanne C; Lyon, Andrew W; Brown, Jacques P; Hanley, David A
2010-05-10
The acid-ash hypothesis, the alkaline diet, and related products are marketed to the general public. Websites, lay literature, and direct mail marketing encourage people to measure their urine pH to assess their health status and their risk of osteoporosis.The objectives of this study were to determine whether 1) low urine pH, or 2) acid excretion in urine [sulfate + chloride + 1.8x phosphate + organic acids] minus [sodium + potassium + 2x calcium + 2x magnesium mEq] in fasting morning urine predict: a) fragility fractures; and b) five-year change of bone mineral density (BMD) in adults. Cohort study: the prospective population-based Canadian Multicentre Osteoporosis Study. Multiple logistic regression was used to examine associations between acid excretion (urine pH and urine acid excretion) in fasting morning with the incidence of fractures (6804 person years). Multiple linear regression was used to examine associations between acid excretion with changes in BMD over 5-years at three sites: lumbar spine, femoral neck, and total hip (n = 651). Potential confounders controlled included: age, gender, family history of osteoporosis, physical activity, smoking, calcium intake, vitamin D status, estrogen status, medications, renal function, urine creatinine, body mass index, and change of body mass index. There were no associations between either urine pH or acid excretion and either the incidence of fractures or change of BMD after adjustment for confounders. Urine pH and urine acid excretion do not predict osteoporosis risk.
Mineral metabolism in dimethylnitrosamine-induced hepatic fibrosis.
George, Joseph
2006-10-01
Complications such as ascites during the pathogenesis of hepatic fibrosis and cirrhosis may lead to several abnormalities in mineral metabolism. In the present investigation, we have monitored serum and liver concentrations of calcium, magnesium, sodium and potassium during experimentally induced hepatic fibrosis in rats. The liver injury was induced by intraperitoneal injections of dimethylnitrosamine (DMN; N-nitrosodimethylamine, NDMA) in doses 1 mg/100 g body weight on 3 consecutive days of each week over a period of 21 days. Calcium, magnesium, sodium and potassium were measured by atomic absorption spectrophotometry in the serum and liver on days 7, 14 and 21 after the start of DMN administration. Negative correlations were observed between liver function tests and serum mineral levels, except with albumin. Calcium, magnesium, potassium and sodium concentrations in the serum were decreased after the induction of liver injury. The liver calcium content was increased after DMN treatment. No change occurred in liver sodium content. However, magnesium and potassium content was significantly reduced in the hepatic tissue. The results suggest that DMN-induced hepatic fibrosis plays certain role in the alteration of essential elements. The low levels of albumin and the related ascites may be one of the major causes of the imbalance of mineral metabolism in hepatic fibrosis and further aggravation of the disease.
NASA Astrophysics Data System (ADS)
Tros, G. H. J.; Lyaruu, D. M.; Vis, R. D.
1993-10-01
A procedure was developed for analysing the effect of fluoride on mineralization in the enamel of neonatal hamster molars during amelogenesis by means of the quantitative determination of the mineral content. In this procedure the distribution of calcium and mineral concentration was determined in sections containing developing tooth enamel mineral embedded in an organic epoxy resin matrix by means of the micro-PIXE technique. This allowed the determination of the calcium content along preselected tracks with a spatial resolution of 2 μm using a microprobe PIXE setup with a 3 MeV proton beam of 10 to 50 pA with a spot size of 2 μm in the track direction. In this procedure the X-ray yield is used as a measure for the calcium content. The thickness of each sample section is determined independently by measuring the energy loss of α-particles from a calibration source upon passing through the sample. The sample is considered as consisting of two bulk materials, allowing the correction for X-ray self-absorption and the calculation of the calcium concentration. The procedure was applied for measuring the distribution of mineral concentration in 2 μm thick sections taken from tooth germs of hamsters administered with NaF. The measurements indicated that a single intraperitoneal administration of 20 mg NaF/kg body weight to 4-to-5-day-old hamsters leads within 24 h to hypermineralization of certain focal enamel surface areas containing cystic lesions under transitional and early secretory ameloblasts. The mineral concentration there is substantially increased due to the fluoride treatment (35%, instead of 5 to 10% as in the controls), indicating that the normal mineralization process has been seriously disturbed. Furthermore it is found that using this technique the mineral concentration peaks at about 70% at the dentine-enamel junction, which is comparable to that reported for human dentine using other techniques.
He, Chuanglong; Xiao, Guiyong; Jin, Xiaobing; Sun, Chenghui; Ma, Peter X.
2011-01-01
We developed a straightforward, fast, and versatile technique to fabricate mineralized nanofibrous polymer scaffolds for bone regeneration in this work. Nanofibrous poly(l-lactic acid) scaffolds were fabricated using both electrospinning and phase separation techniques. An electrodeposition process was designed to deposit calcium phosphate on the nanofibrous scaffolds. Such scaffolds contain a high quality mineral coating on the fiber surface with tunable surface topography and chemical composition by varying the processing parameters, which can mimic the composition and structure of natural bone extracellular matrix and provide a more biocompatible interface for bone regeneration. PMID:21673827
Ubiquitylation Functions in the Calcium Carbonate Biomineralization in the Extracellular Matrix
Fang, Dong; Pan, Cong; Lin, Huijuan; Lin, Ya; Xu, Guangrui; Zhang, Guiyou; Wang, Hongzhong; Xie, Liping; Zhang, Rongqing
2012-01-01
Mollusks shell formation is mediated by matrix proteins and many of these proteins have been identified and characterized. However, the mechanisms of protein control remain unknown. Here, we report the ubiquitylation of matrix proteins in the prismatic layer of the pearl oyster, Pinctada fucata. The presence of ubiquitylated proteins in the prismatic layer of the shell was detected with a combination of western blot and immunogold assays. The coupled ubiquitins were separated and identified by Edman degradation and liquid chromatography/mass spectrometry (LC/MS). Antibody injection in vivo resulted in large amounts of calcium carbonate randomly accumulating on the surface of the nacreous layer. These ubiquitylated proteins could bind to specific faces of calcite and aragonite, which are the two main mineral components of the shell. In the in vitro calcium carbonate crystallization assay, they could reduce the rate of calcium carbonate precipitation and induce the calcite formation. Furthermore, when the attached ubiquitins were removed, the functions of the EDTA-soluble matrix of the prismatic layer were changed. Their potency to inhibit precipitation of calcium carbonate was decreased and their influence on the morphology of calcium carbonate crystals was changed. Taken together, ubiquitylation is involved in shell formation. Although the ubiquitylation is supposed to be involved in every aspect of biophysical processes, our work connected the biomineralization-related proteins and the ubiquitylation mechanism in the extracellular matrix for the first time. This would promote our understanding of the shell biomineralization and the ubiquitylation processes. PMID:22558208
DOE Office of Scientific and Technical Information (OSTI.GOV)
Obrant, K.J.; Odselius, R.
1984-01-01
Energy dispersive X-ray microanalysis (EDX) (or electron microprobe analysis) of the relative intensity for calcium in different bone trabeculae from the tibia epiphysis, and in different parts of one and the same trabecula, was performed on 3 patients who had earlier had a fracture of the ipsilateral tibia-diaphysis. The variation in intensity was compared with the histochemical patterns obtained with both the Goldner and the von Kossa staining techniques for detecting calcium in tissues. Previously reported calcium distribution features, found to be typical for posttraumatic osteopenia, such as striated mineralization patterns in individual trabeculae and large differences in mineralization levelmore » between different trabeculae, could be verified both by means of the two histochemical procedures and from the electron microprobe analysis. A pronounced difference was observed, however, between the two histochemical staining techniques as regards their sensitivity to detect calcium. To judge from the values obtained from the EDX measurements, the sensitivity of the Goldner technique should be more than ten times higher than that of von Kossa. The EDX measurements gave more detailed information than either of the two histochemical techniques: great variations in the intensity of the calcium peak were found in trabeculae stained as unmineralized as well as mineralized.« less
Rapidly Assessing Changes in Bone Mineral Balance Using Natural Stable Calcium Isotopes
NASA Technical Reports Server (NTRS)
Morgan, J. L. L.; Gordon, G. W.; Romaniello, S. J.; Skulan, J. L.; Smith, S. M.; Anbar, A. D.
2011-01-01
We demonstrate that variations in the Ca isotope ratios in urine rapidly and quantitatively reflect changes in bone mineral balance. This variation occurs because bone formation depletes soft tissue of light Ca isotopes, while bone resorption releases that isotopically light Ca back into soft tissue. In a study of 12 individuals confined to bed rest, a condition known to induce bone resorption, we show that Ca isotope ratios shift in a direction consistent with net bone loss after just 7 days, long before detectible changes in bone density occur. Consistent with this interpretation, the Ca isotope variations track changes observed in N-teleopeptide, a bone resorption biomarker, while bone-specific alkaline phosphatase, a bone formation biomarker, is unchanged. Ca isotopes can in principle be used to quantify net changes in bone mass. Ca isotopes indicate an average loss of 0.62 +/- 0.16 % in bone mass over the course of this 30-day study. The Ca isotope technique should accelerate the pace of discovery of new treatments for bone disease and provide novel insights into the dynamics of bone metabolism.
NASA Astrophysics Data System (ADS)
Frost, Ray L.; Xi, Yunfei; Scholz, Ricardo; Lima, Rosa Malena Fernandes; Horta, Laura Frota Campos; Lopez, Andres
2013-11-01
The objective of this work is to determine the thermal stability and vibrational spectra of datolite CaBSiO4(OH) and relate these properties to the structure of the mineral. The thermal analysis of datolite shows a mass loss of 5.83% over a 700-775 °C temperature range. This mass loss corresponds to 1 water (H2O) molecules pfu. A quantitative chemical analysis using electron probe was undertaken. The Raman spectrum of datolite is characterized by bands at 917 and 1077 cm-1 assigned to the symmetric stretching modes of BO and SiO tetrahedra. A very intense Raman band is observed at 3498 cm-1 assigned to the stretching vibration of the OH units in the structure of datolite. BOH out-of-plane vibrations are characterized by the infrared band at 782 cm-1. The vibrational spectra are based upon the structure of datolite based on sheets of four- and eight-membered rings of alternating SiO4 and BO3(OH) tetrahedra with the sheets bonded together by calcium atoms.
Oyetayo, Folake Lucy; Ibitoye, Muyiwa Femi
2012-07-01
The fruit of the cherry tomato (Lycopersicon esculentum (Solanaceae)) was analysed for mineral and antinutrient composition. Phosphorus (33.04 ± 0.21 mg/100g) was the most abundant mineral in the fruit, followed by calcium (32.04 ± 0.06 mg/100 g), and potassium (11.9 ± 0.1 mg/100 g) and manganese (9.55 ± 0.28 mg/100 g) were also present in appreciable quantities. Antinutrients, including phytate, glycoside, saponin and tannin, were screened and quantified. Phytate (112.82 ± 0.1 mg/100 g), glycoside (2.33 ± 0.00 mg/100 g), saponin (1.31 ± 0.00 mg/100g) and tannin (0.21 ± 0.00 mg/100 g) were present in the fruit but phlobatanin and glycosides with steroidal rings were not found. The calculated calcium:phytate ratio of the fruits was below the critical value and the calculated [calcium] [phytate]:[zinc] molar ratio was less than the critical value. The calcium:phosphorus ratio (0.97 mg/100 g) shows the fruit to be a good source of food nutrients, while the sodium:potassium value was less than 1. Ca/P ratio below 0.5 indicates deficiency of these minerals while Na/K ratio above 1 is detrimental because of excessive sodium levels. The results of the study generally revealed the fruit to be rich in minerals but containing insufficient quantities of antinutrients to result in poor mineral bioavailability.
Sheedy, John R; Gooley, Paul R; Nahid, Amsha; Tull, Dedreia L; McConville, Malcolm J; Kukuljan, Sonja; Nowson, Caryl A; Daly, Robin M; Ebeling, Peter R
2014-11-01
The musculoskeletal benefits of calcium and vitamin-D3 supplementation and exercise have been extensively studied, but the effect on metabolism remains contentious. Urine samples were analyzed by (1)H-NMR spectroscopy from participants recruited for an 18-month, randomized controlled trial of a multi-component exercise program and calcium and vitamin-D3 fortified milk consumption. It was shown previously that no increase in musculoskeletal composition was observed for participants assigned to the calcium and vitamin-D3 intervention, but exercise resulted in increased bone mineral density, total lean body mass, and muscle strength. Retrospective metabolomics analysis of urine samples from patients involved in this study revealed no distinct changes in the urinary metabolome in response to the calcium and vitamin-D3 intervention, but significant changes followed the exercise intervention, notably a reduction in creatinine and an increase in choline, guanidinoacetate, and hypoxanthine (p < 0.001, fold change > 1.5). These metabolites are intrinsically involved in anaerobic ATP synthesis, intracellular buffering, and methyl-balance regulation. The exercise intervention had a marked effect on the urine metabolome and markers of muscle turnover but none of these metabolites were obvious markers of bone turnover. Measurement of specific urinary exercise biomarkers may provide a basis for monitoring performance and metabolic response to exercise regimes.
Aluminum and Phthalates in Calcium Gluconate: Contribution From Glass and Plastic Packaging.
Yokel, Robert A; Unrine, Jason M
2017-01-01
Aluminum contamination of parenteral nutrition solutions has been documented for 3 decades. It can result in elevated blood, bone, and whole body aluminum levels associated with neurotoxicity, reduced bone mass and mineral content, and perhaps hepatotoxicity. The primary aluminum source among parenteral nutrition components is glass-packaged calcium gluconate, in which aluminum concentration in the past 3 decades has averaged approximately 4000 μg/L, compared with <200 μg/L in plastic container-packaged calcium gluconate. A concern about plastic packaging is leaching of plasticizers, including phthalates, which have the potential to cause endocrine (male reproductive system) disruption and neurotoxicity. Aluminum was quantified in samples collected periodically for more than 2 years from 3 calcium gluconate sources used to prepare parenteral nutrition solutions; 2 packaged in glass (from France and the United States) and 1 in plastic (from Germany); in a recently released plastic-packaged solution (from the United States); and in the 2 glass containers. Phthalate concentration was determined in selected samples of each product and leachate of the plastic containers. The initial aluminum concentration was approximately 5000 μg/L in the 2 glass-packaged products and approximately 20 μg/L in the plastic-packaged product, and increased approximately 30%, 50%, and 100% in 2 years, respectively. The aluminum concentration in a recently released Calcium Gluconate Injection USP was approximately 320 μg/L. Phthalates were not detected in any calcium gluconate solutions or leachates. Plastic packaging greatly reduces the contribution of aluminum to parenteral nutrition solutions from calcium gluconate compared with the glass-packaged product.
Bone mineral density trends in Indian patients with hyperthyroidism--effect of antithyroid therapy.
Dhanwal, Dinesh Kumar; Gupta, Nandita
2011-09-01
Hyperthyroidism is associated with bone loss, which is reversible after treatment. The extent of reversibility of loss of bone mass density (BMD) in hyperthyroid patients after treatment especially at forearm is not clear. Therefore, the present study was conducted to assess degree of reversibility in bone mineral density following one-year medical treatment in Indian patients with hyperthyroidism. A total of 30 consecutive patients with hyperthyroidism were included in this one year study at All India Institute of Medical Sciences, New Delhi, India. All the patients were assessed for parameters of bone mineral homeostasis such as calcium, phosphorous, alkaline phosphatase, 25-hydroxy vitamin D [25 (OH) D], parathyroid hormone (PTH) at the time of diagnosis and after one year medical treatment. Bone mineral density was measured using Hologic DXA scan at hip, spine and forearm. All the patients received medical therapy with carbimazole. The parameters of bone homeostasis and bone mineral density at base line and after one year medical treatment was compared. All patients attained euthyroid status after eight weeks of carbimazole therapy. Parameters of bone homeostasis such as calcium, phosphorous, 25 (OH) D and PTH did not show any significant change from base line. Bone mineral density expressed as bone mineral content in gm/cm2 at left hip neck, trochanteric and intertrochanteric region was significantly higher after carbimazole therapy (745.2 +/- 127.6 gm/cm2 vs. 688.2 +/- 123.5 gm/cm2; p = 0.02, 573.4 +/- 109.9 gm/cm2 vs. 641.0 +/- 138.0 gm/cm2, p = 0.005 and 1008.6 +/- 185.5 gm/cm2 vs. 938.0 +/- 145.3 gm/cm2 p = 0.0131 respectively). Bone mineral density at lumbar spine expressed as either T and Z score was significantly higher after treatment (10 months of euthyroid state) (-0.6 +/- 1.3 vs. -1.7 +/- 1.2, p = 0.013 and -0.4 +/- 1.2 vs. -1.4 +/- 1.2, p = 0.012 respectively). However Bone mineral measures as T and Z score at left forearm decreased significantly after one year of medical therapy. In Indian patients with hyperthyroidism, the pattern of recovery of bone loss after one year of antithyroid therapy suggests early recovery at hip and lumbar spine and deterioration at forearm.
Leaf Protein and Mineral Concentrations across the “Miracle Tree” Genus Moringa
Sankaran, Renuka P.; Fahey, Jed W.; Grusak, Michael A.; Odee, David; Nouman, Wasif
2016-01-01
The moringa tree Moringa oleifera is a fast-growing, drought-resistant tree cultivated across the lowland dry tropics worldwide for its nutritious leaves. Despite its nutritious reputation, there has been no systematic survey of the variation in leaf nutritional quality across M. oleifera grown worldwide, or of the other species of the genus. To guide informed use of moringa, we surveyed protein, macro-, and micro- nutrients across 67 common garden samples of 12 Moringa taxa, including 23 samples of M. oleifera. Moringa oleifera, M. concanensis, M. stenopetala, an M. concanensis X oleifera hybrid, and M. longituba were highest in protein, with M. ruspoliana having the highest calcium levels. A protein-dry leaf mass tradeoff may preclude certain breeding possibilities, e.g. maximally high protein with large leaflets. These findings identify clear priorities and limitations for improved moringa varieties with traits such as high protein, calcium, or ease of preparation. PMID:27459315
Leaf Protein and Mineral Concentrations across the "Miracle Tree" Genus Moringa.
Olson, Mark E; Sankaran, Renuka P; Fahey, Jed W; Grusak, Michael A; Odee, David; Nouman, Wasif
2016-01-01
The moringa tree Moringa oleifera is a fast-growing, drought-resistant tree cultivated across the lowland dry tropics worldwide for its nutritious leaves. Despite its nutritious reputation, there has been no systematic survey of the variation in leaf nutritional quality across M. oleifera grown worldwide, or of the other species of the genus. To guide informed use of moringa, we surveyed protein, macro-, and micro- nutrients across 67 common garden samples of 12 Moringa taxa, including 23 samples of M. oleifera. Moringa oleifera, M. concanensis, M. stenopetala, an M. concanensis X oleifera hybrid, and M. longituba were highest in protein, with M. ruspoliana having the highest calcium levels. A protein-dry leaf mass tradeoff may preclude certain breeding possibilities, e.g. maximally high protein with large leaflets. These findings identify clear priorities and limitations for improved moringa varieties with traits such as high protein, calcium, or ease of preparation.
Weber, Thomas J; Koh, James; Thomas, Samantha M; Hogue, Joyce A; Scheri, Randall P; Roman, Sanziana A; Sosa, Julie A
2017-09-01
A subset of PHPT patients exhibit a more severe disease phenotype characterized by bone loss, fractures, recurrent nephrolithiasis, and other dysfunctions, but the underlying reasons for this disparity in clinical presentation remain unknown. We sought to identify new mechanistic indices that could inform more personalized management of PHPT. Pre-, peri-, and postoperative data and demographic, clinical, and pathological information from patients undergoing parathyroidectomy for PHPT were collected. Univariate and partial Spearman correlation was used to estimate the association of parathyroid tumor calcium sensing capacity with select variables. An unselected series of 237 patients aged >18years and undergoing parathyroidectomy for PHPT were enrolled. Calcium sensing capacity, expressed as the concentration required for half-maximal biochemical response (EC50), was evaluated in parathyroid tumors from an unselected series of 74 patients and assessed for association with clinical parameters. The hypothesis was that greater disease severity would be associated with attenuated calcium sensitivity and biochemically autonomous parathyroid tumor behavior. Parathyroid tumors segregated into two distinct groups of calcium responsiveness (EC50<3.0 and ≥3.0mM). The low EC50 group (n=27) demonstrated a mean calcium EC50 value of 2.49mM [95% confidence interval (CI): 2.43-2.54mM], consistent with reference normal activity. In contrast, the high EC50 group (n=47) displayed attenuated calcium sensitivity with a mean EC50 value of 3.48mM [95% CI: 3.41-3.55mM]. Retrospective analysis of the clinical registry data suggested that high calcium EC50 patients presented with a more significant preoperative bone mineral density (BMD) deficit with a t-score of -2.7, (95% CI: -3.4 to -1.9) versus 0.9, (95% CI: -2.1 to -0.4) in low EC50 patients (p<0.001). After adjusting for gender, age, BMI, 25 OH vitamin D level and preoperative iPTH, lowest t-score and calcium EC50 were inversely correlated, with a partial Spearman correlation coefficient of -0.35 (p=0.02). Impaired calcium sensing in parathyroid tumors is selectively observed in a subset of patients with more severe bone mineral density deficit. Assessment of parathyroid tumor biochemical behavior may be a useful predictor of disease severity as measured by bone mineral density in patients with PHPT. Copyright © 2017 Elsevier Inc. All rights reserved.
[Investigation of adolescents' bone metabolism in the western part of Transdanubia].
Csákváry, Violetta; Puskás, Tamás; Bödecs, Tamás; Lôcsei, Zoltán; Oroszlán, György; Kovács, L Gábor; Toldy, Erzsébet
2009-10-25
Childhood reference range based on the age is not available in Hungary, therefore the diagnosis and therapy of bone metabolic diseases of childhood are subject to difficulties. The aim of this work is to provide information about the adolescents' results of bone mineral density and bone biomarkers. Measurements were performed in 169 healthy adolescents (98 girls, 71 boys, age: 17.0+/-1.2 years). Bone mineral content (BMC) and bone mineral density (BMD) of the lumbar spine were measured using Double X-ray Absorptiometry (DXA, LUNAR, GE Health Care, USA) and Z-score values were analyzed using different reference population. In the serum, bone biomarkers osteocalcin (OC) and beta-crosslaps (beta-Cl) were measured by a fully automated, electrochemiluminescence immunoassay method (Elecsys-2010, Roche). Data were analyzed according to gender and the Tanner stage and grade system. Associations between body mass index (BMI), calcium intake, consumption of soft drinks and coke, and physical exercise were investigated. BMC values for both age groups were significantly elevated in boys of the Tanner stage V. (15-16 years: 62.9+/-14.3 g; 17-19 years: 69.8+/-9.3g) than in girls (58.1+/-10.4; 61.6+/-8.5 g) (p<0.001). BMD values were higher in girls, than in boys (1.17+/-0.12 g/cm 2 vs. 1.13+/-0.11 g/cm 2) (p<0.05). OC and beta-Cl levels showed negative correlation with age in both gender (p<0.01), while OC and beta-Cl levels were higher in boys, than in girls (p<0.001). Elevation of BMC and BMD values were associated with increase of BMI in both gender (p<0.05), but the biomarkers in thin girls were higher, than in overweight girls (p<0.05). Authors obtained excellent correlations between the BMD-Z-score values compared to the German standard and to their own population (girls: r=0.97, boys: 0.88), but the absolute values significantly differed from one another. 80% of adolescents are on a diet with insufficient calcium intake, while 38% of them do not play sport regularly. Excessive intake of soft drinks was determined in 60% of adolescents. In the case of insufficient calcium intake (4.7%, 6/127), low bone mass was measured using the Z-score of the German reference values. Among children with adequate calcium intake, BMD assessed by DXA was normal. These data help to determine normal reference values among healthy high school students. Further studies are needed in wider range of young population for the establishment of Hungarian reference values of bone markers.
Interaction between Bisphosphonates and Mineral Water: Study of Oral Risedronate Absorption in Rats.
Itoh, Akihisa; Akagi, Yuuki; Shimomura, Hitoshi; Aoyama, Takao
2016-01-01
Bisphosphonates are antiosteoporotic agents prescribed for patients with osteoporosis. Drug package inserts for bisphosphonate supplements indicate that their bioavailability is reduced by high levels of metal cations (Ca(2+), Mg(2+), etc.). However, standards for these cations in water used for taking risedronate have not been defined. Here, we examined the effect of calcium and magnesium in mineral waters on the bioavailability of the third-generation bisphosphonate, risedronate, following oral administration in rats. As risedronate is unchanged and eliminated renally, risedronate absorption was estimated from the amount excreted in the urine. Risedronate was dissolved in mineral water samples and administered orally at 0.35 mg/kg. Urine samples were collected for 24 h after dosing. Risedronate was extracted from urine using ion-pair solid-phase cartridges and quantified by HPLC with UV detection (262 nm). Cumulative recovery of risedronate was calculated from the amount excreted in the urine. The 24-h recovery of risedronate from evian® (0.32±0.02% [mean±standard deviation (S.D.)], n=4) and Contrex(®) (0.22±0.05%) mineral waters was significantly lower than that from tap water (0.47±0.04%, p<0.01). Absorption of risedronate in calcium chloride and magnesium chloride aqueous solutions of the same hardness (822 mg/L) was 54% (0.27±0.04%) and 12% (0.51±0.08%) lower, respectively, compared with ultrapure water; suggesting that absorption of risedronate declines as the calcium concentration of mineral waters increases. Consumption of mineral waters containing high levels of calcium (80 mg/L or above), such as evian® and Contrex(®), is therefore not recommended when taking risedronate.
Mineral metabolism, mortality, and morbidity in maintenance hemodialysis.
Block, Geoffrey A; Klassen, Preston S; Lazarus, J Michael; Ofsthun, Norma; Lowrie, Edmund G; Chertow, Glenn M
2004-08-01
Mortality rates in ESRD are unacceptably high. Disorders of mineral metabolism (hyperphosphatemia, hypercalcemia, and secondary hyperparathyroidism) are potentially modifiable. For determining associations among disorders of mineral metabolism, mortality, and morbidity in hemodialysis patients, data on 40,538 hemodialysis patients with at least one determination of serum phosphorus and calcium during the last 3 mo of 1997 were analyzed. Unadjusted, case mix-adjusted, and multivariable-adjusted relative risks of death were calculated for categories of serum phosphorus, calcium, calcium x phosphorus product, and intact parathyroid hormone (PTH) using proportional hazards regression. Also determined was whether disorders of mineral metabolism were associated with all-cause, cardiovascular, infection-related, fracture-related, and vascular access-related hospitalization. After adjustment for case mix and laboratory variables, serum phosphorus concentrations >5.0 mg/dl were associated with an increased relative risk of death (1.07, 1.25, 1.43, 1.67, and 2.02 for serum phosphorus 5.0 to 6.0, 6.0 to 7.0, 7.0 to 8.0, 8.0 to 9.0, and >/=9.0 mg/dl). Higher adjusted serum calcium concentrations were also associated with an increased risk of death, even when examined within narrow ranges of serum phosphorus. Moderate to severe hyperparathyroidism (PTH concentrations >/=600 pg/ml) was associated with an increase in the relative risk of death, whereas more modest increases in PTH were not. When examined collectively, the population attributable risk percentage for disorders of mineral metabolism was 17.5%, owing largely to the high prevalence of hyperphosphatemia. Hyperphosphatemia and hyperparathyroidism were significantly associated with all-cause, cardiovascular, and fracture-related hospitalization. Disorders of mineral metabolism are independently associated with mortality and morbidity associated with cardiovascular disease and fracture in hemodialysis patients.
Pereira, Cristiane Pavan; Amaral, Denise Johnsson Campos; Funke, Vaneuza Araujo Moreira; Borba, Victória Zeghbi Cochenski
The aim of this study was to evaluate the prevalence of pre-sarcopenia and bone mineral density after hematopoietic stem cell transplantation. The study group consisted of over 18-year-old patients who had been submitted to allogeneic transplantation at least one year previously. Patients and healthy controls were matched by sex, ethnic background, age, and body mass index. Body composition and bone mineral density were measured by dual-energy X-ray absorptiometry. A 24-h food recall and food frequency survey were performed. The biochemical evaluation included calcium, parathormone and vitamin D. Eighty-seven patients (52 men; age: 37.2±12.7 years; body mass index: 25±4.5kg/m 2 ) were compared to 68 controls [31 men; age 35.4±15.5 years (p=0.467); body mass index 25.05±3.7kg/m 2 (p=0.927)]. There was no significant difference in the dietary intake between patients and controls. The mean levels of vitamin D were 23.5±10.3ng/mL; 29 patients (41.0%) had insufficient and 26 (37.14%) deficient levels. A higher prevalence of reduced bone mineral density was observed in 24 patients (25%) compared to 12 controls (19.1% - p<0.001). Pre-sarcopenia was diagnosed in 14 (14.4%) patients and none of the controls (p=0.05). There was a higher prevalence of pre-sarcopenia (66%) in patients with grades III and IV compared to those with grades 0-II graft-versus-host disease (10.9%) (p=0.004). patients submitted to transplantation had a higher prevalence of pre-sarcopenia and greater changes in bone mineral density compared to controls; the severity of graft-versus-host disease had an impact on the prevalence of pre-sarcopenia. Copyright © 2017 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.
Calcium carbonate mineralization mediated by in vitro cultured mantle cells from Pinctada fucata.
Kong, Wei; Li, Shiguo; Xiang, Liang; Xie, Liping; Zhang, Rongqing
2015-08-07
Formation of the molluscan shell is believed to be an extracellular event mediated by matrix proteins. We report calcium carbonate mineralization mediated by Pinctada fucata mantle cells. Crystals only appeared when mantle cells were present in the crystallization solution. These crystals were piled up in highly ordered units and showed the typical characteristics of biomineralization products. A thin organic framework was observed after dissolving the crystals in EDTA. Some crystals had etched surfaces with a much smoother appearance than other parts. Mantle cells were observed to be attached to some of these smooth surfaces. These results suggest that mantle cells may be directly involved in the nucleation and remodeling process of calcium carbonate mineralization. Our result demonstrate the practicability of studying the mantle cell mechanism of biomineralization and contribute to the overall understanding of the shell formation process. Copyright © 2015 Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Vitamin D is the critical hormone for intestinal absorption of calcium. Optimal calcium absorption is important for proper mineralization of bone in the prevention of osteoporosis and osteoporotic fractures, among other important functions. Diseases associated with gut inflammation, such as Crohn's ...
Mineral resource of the month: Phosphate rock
Jasinski, Stephen M.
2013-01-01
As a mineral resource, “phosphate rock” is defined as unprocessed ore and processed concentrates that contain some form of apatite, a group of calcium phosphate minerals that is the primary source for phosphorus in phosphate fertilizers, which are vital to agriculture.
Incidence of Osteoporosis in Patients with Urolithiasis
Bijelic, Radojka; Milicevic, Snjezana; Balaban, Jagoda
2014-01-01
ABSTRACT Introduction. Clinical researches have shown an increased bone disintegration and lower bone mass in patients with calcium urolithiasis. Goal. The goal of our research was to establish the incidence of osteoporosis in adult patients with calcium urolithiasis, on the basis of measuring mineral bone density, using DEXA method, with a special reflection on age subgroups. Material and methods. Clinical research was prospective and it was implemented at the University Clinical Center of Banja Luka, at the Clinic for Endocrinology, Diabetes and Metabolic Diseases and at the Urology Clinic. Material in this research consisted of patients divided in two groups, a working and a control group. One hundred and twenty (120) patients were included in both these groups, divided in three age subgroups: 20-40, 40-60 and over 60. The working group consisted of the patients with calcium urolithiasis and the control group consisted of patients without calcium urolithiasis. Establishing of mineral bone density at L2-L4 of lumbal spine vertebrae and hip was done for the patients in both these groups, using DEXA method. Results. Analysis of mineral bone density using DEXA method in patients in age groups of working and control groups, as well as in the total sample of working and control groups, have shown that the patients of the working group, over 60, had a decreased mineral bone density (30% of osteopenia and 15% osteoporosis) significantly more expressed when compared to the other two age groups (12.5% in the subgroup 20-40 and 17.5% in the subgroup 40-60), which presents a statistically significant difference (p<0.05). In the control group, when taking into account age groups, osteopenia and osteoporosis were marked in 37.5% and 2.5% in the group of patients over 60, whereas in the youngest population, 5% of osteopenia was found, which presents a statistically significant difference (p<0.05). When observing the total sample of working and control group, there was a statistically significant difference in the working and control group (p<0.01); incidence of osteoporosis in the working group amounted to 7.5% and in the control group it was 0.8%. Conclusion. Urolithiasis and osteoporosis are two multifactorial diseases which are evidently reciprocal. This is why we suggest that educating the population about the risk factors for occurrence of these diseases as well as preventive measures that may contribute to their decrease should begin as early as possible. PMID:25568567
Chen, Yu-Ming; Ho, Suzanne C; Lam, Silvia S H; Ho, Susan S S; Woo, Jean L F
2004-01-01
Many studies have shown that soy isoflavones have an effect in preventing estrogen-related bone loss, but no data reported whether such an effect could be influenced by other important factors affecting bone loss. This study examines whether the associations between isoflavone supplementation and rates of change in bone mineral content (BMC) could be modified by years since menopause (YSM), body weight (BW), and dietary calcium intake in postmenopausal Chinese women aged 48 to 62 years. A group of 203 eligible women were randomly assigned to three treatment groups: placebo (daily dose of 0 mg isoflavones + 500 mg calcium, n = 67), mid-dose (40 mg isoflavones + 500 mg calcium, n = 68); and high-dose (80 mg isoflavones + 500 mg calcium, n = 68). Bone mineral density (BMD) and BMC at the whole body, spine, and hip were measured by dual-energy x-ray absorptiometry at baseline and posttreatment after 1 year. YSM, BW, and dietary calcium intake stratified analyses were performed to evaluate whether the associations between isoflavones supplementation and BMC change rates were varied with these factors. Both univariate and multivariate analyses observed significant favorable effect of isoflavone supplementation on rates of change in BMC at the total hip and trochanter among later postmenopausal women (> 4 y), in women with lower BW (< or =median, 55.5 kg), or among women with lower level of calcium intake (< or =median, 1095 mg/d). The independent effect of soy on the maintenance of hip BMC is more marked in women in later menopause or those with lower BW or calcium intake.
Capping a Pulpotomy with Calcium Aluminosilicate Cement: Comparison to Mineral Trioxide Aggregates
Kramer, Phillip R.; Woodmansey, Karl F.; White, Robert; Primus, Carolyn M.; Opperman, Lynne A.
2014-01-01
Introduction Calcium aluminate cements have shown little affinity for bacterial growth, low toxicity, and immunogenicity when used as a restoration material, but calcium aluminate cements have not been tested in vivo in pulpotomy procedures. Methods To address this question, a calcium aluminate cement (Quick-Set) was tested along with 2 mineral trioxide aggregates, ProRoot MTA and MTA Plus. These cements were used as a capping agent after pulpotomy. Control rats had no pulpotomy, or the pulpotomy was not capped. Proinflammatory cytokines interleukin (IL)-1β and IL-1α were measured, and histology was performed at 30 and 60 days after capping. The nociceptive response was determined by measuring the lengthening of the rat's meal duration. Results and Conclusions: IL-1β and IL-1α concentrations were reduced in the capped teeth, but no differences were observed among the 3 cements. Dentinal bridging could be detected at both 30 and 60 days with each of the 3 cements, and the pulps were still vital 60 days after capping. Meal duration significantly shortened after placement of the 3 different cements, indicating a nociceptive response, but there were no differences among the materials. Calcium aluminate cements had similar properties to mineral trioxide aggregates and is a viable option for pulpotomy procedures. PMID:25146026
Ryan, Zachary C.; Craig, Theodore A.; Filoteo, Adelaida G.; Westendorf, Jennifer J.; Cartwright, Elizabeth J.; Neyses, Ludwig; Strehler, Emanuel E.; Kumar, Rajiv
2016-01-01
The physiological importance of the intestinal plasma membrane calcium pump, isoform 1, (Pmca1, Atp2b1), in calcium absorption and homeostasis has not been previously demonstrated in vivo. Since global germ-line deletion of the Pmca1 in mice is associated with embryonic lethality, we selectively deleted the Pmca1 in intestinal absorptive cells. Mice with loxP sites flanking exon 2 of the Pmca1 gene (Pmca1fl/fl) were crossed with mice expressing Cre recombinase in the intestine under control of the villin promoter to give mice in which the Pmca1 had been deleted in the intestine (Pmca1EKO mice). Pmca1EKO mice were born at a reduced frequency and were small at the time of birth when compared to wild-type (Wt) litter mates. At two months of age, Pmca1EKO mice fed a 0.81% calcium, 0.34% phosphorus, normal vitamin D diet had reduced whole body bone mineral density (P <0.037), and reduced femoral bone mineral density (P <0.015). There was a trend towards lower serum calcium and higher serum parathyroid hormone (PTH) and 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) concentrations in Pmca1EKO mice compared to Wt mice but the changes were not statistically significant. The urinary phosphorus/creatinine ratio was increased in Pmca1EKO mice (P <0.004). Following the administration of 200 ng of 1α,25(OH)2D3 intraperitoneally to Wt mice, active intestinal calcium transport increased ∼2-fold, whereas Pmca1EKO mice administered an equal amount of 1α,25(OH)2D3 failed to show an increase in active calcium transport. Deletion of the Pmca1 in the intestine is associated with reduced growth and bone mineralization, and a failure to up-regulate calcium absorption in response to 1α,25(OH)2D3. PMID:26392310
Mammalian Gravity Receptors: Structure and Metabolism
NASA Technical Reports Server (NTRS)
Ross, M. D.
1985-01-01
Calcium metabolism in mammalian gravity receptors is examined. To accomplish this objective it is necessary to study both the mineral deposits of the receptors, the otoconia, and the sensory areas themselves, the saccular and utricular maculas. The main focus was to elucidate the natures of the organic and inorganic phases of the crystalline masses, first in rat otoconia but more recently in otoliths and otoconia of a comparative series of vertebrates. Some of the ultrastructural findings in rat maculas, however, have prompted a more thorough study of the organization of the hair cells and innervation patterns in graviceptors.
Ocean Acidification Causes Increased Calcium Carbonate Turnover during Larval Shell Formation
NASA Astrophysics Data System (ADS)
Frieder, C.; Pan, F.; Applebaum, S.; Manahan, D. T.
2016-02-01
Mollusca is a major taxon for studies of the evolution and mechanisms of calcification. Under current and future ocean change scenarios, decreases in shell size have been observed in many molluscan species during early development. The mechanistic basis for these decreases are of significant interest. In this study, Pacific oyster larvae (Crassostrea gigas) reared at aragonite undersaturation (Ω < 1) accreted just a third of shell mass relative to control (Ω >> 1). Coupling radioisotope tracer assays with mineral mass measurements allowed calculation of calcification budgets for first shell formation in veliger stage larvae. Three primary mechanisms (in order of increasing effect) contributed to the change in shell mass at undersaturation: delayed onset of calcification, increased dissolution rates, and decreased net calcification rates. The observation of dissolution indicates turnover of the newly formed shell, and physicochemical constraints of undersaturation provide a mechanistic basis for decreased calcification.
Human colon tissue in organ culture: calcium and multi-mineral-induced mucosal differentiation
Dame, Michael K.; Veerapaneni, Indiradevi; Bhagavathula, Narasimharao; Naik, Madhav; Varani, James
2011-01-01
We have recently shown that a multi-mineral extract from the marine red algae, Lithothamnion calcareum, suppresses colon polyp formation and inflammation in mice. In the present study, we used intact human colon tissue in organ culture to compare responses initiated by Ca2+ supplementation versus the multi-mineral extract. Normal human colon tissue was treated for 2 d in culture with various concentrations of calcium or the mineral-rich extract. The tissue was then prepared for histology/immunohistochemistry, and the culture supernatants were assayed for levels of type I procollagen and type I collagen. At higher Ca2+ concentrations or with the mineral-rich extract, proliferation of epithelial cells at the base and walls of the mucosal crypts was suppressed, as visualized by reduced Ki67 staining. E-cadherin, a marker of differentiation, was more strongly expressed at the upper third of the crypt and at the luminal surface. Treatment with Ca2+ or with the multi-mineral extract influenced collagen turnover, with decreased procollagen and increased type I collagen. These data suggest that calcium or mineral-rich extract has the capacity to (1) promote differentiation in human colon tissue in organ culture and (2) modulate stromal function as assessed by increased levels of type I collagen. Taken together, these data suggest that human colon tissue in organ culture (supporting in vivo finding in mice) will provide a valuable model for the preclinical assessment of agents that regulate growth and differentiation in the colonic mucosa. PMID:21104039
Kingman, Joshua; Uitto, Jouni; Li, Qiaoli
2017-06-13
Generalized arterial calcification of infancy (GACI) is an autosomal recessive disorder caused by mutations in the ENPP1 gene. It is characterized by mineralization of the arterial blood vessels, often diagnosed prenatally, and associated with death in early childhood. There is no effective treatment for this devastating disorder. We previously characterized the Enpp1asjmutant mouse as a model of GACI, and we have now explored the effect of elevated dietary magnesium (five-fold) in pregnant mothers and continuing for the first 14 weeks of postnatal life. The mothers were kept on either control diet or experimental diet supplemented with magnesium. Upon weaning at 4 weeks of age the pups were placed either on control diet or high magnesium diet. The degree of mineralization was assessed at 14 weeks of age by histopathology and a chemical calcium assay in muzzle skin, kidney and aorta. Mice placed on high magnesium diet showed little, if any, evidence of mineralization when their corresponding mothers were also placed on diet enriched with magnesium during pregnancy and nursing. The reduced ectopic mineralization in these mice was accompanied by increased calcium and magnesium content in the urine, suggesting that magnesium competes calcium-phosphate binding thereby preventing the mineral deposition. These results have implications for dietary management of pregnancies in which the fetus is suspected of having GACI. Moreover, augmenting a diet with high magnesium may be beneficial for other ectopic mineralization diseases, including nephrocalcinosis.
Ansari, T M; Marr, I L; Coats, A M
2001-02-01
This study was carried out to characterise the mineralogical forms of barium and the trace heavy metal impurities in commercial barytes of different origins using electron probe microanalysis (EPMA), X-ray diffraction (XRD) and inductively coupled plasma mass spectrometry (ICP-MS). Qualitative EPMA results show the presence of typically eight different minerals in commercial barytes including barite (BaSO4), barium feldspar, galena (PbS), pyrite (FeS2), sphalerite (ZnS), quartz (SiO2), and silicates, etc. Quantitative EPMA confirms that the barite crystals in the barytes contain some strontium and a little calcium, whereas trace heavy metals occur in the associated minerals. Analysis of aqua regia extracts of barytes samples by ICP-MS has shown the presence of a large number of elements in the associated minerals. Arsenic, copper and zinc concentrations correlate closely in all 10 samples. The findings suggest that barytes is not, as traditionally thought, an inert mineral, but is a potentially toxic substance due to its associated heavy metal impurities, which can be determined by an aqua regia digest without the need for complete dissolution of the barite itself. X-ray powder diffraction was not informative as the complex barite pattern masks the very weak lines from the small amounts of associated minerals.
Chen, Liang; Song, Wei; Markel, David C; Shi, Tong; Muzik, Otto; Matthew, Howard; Ren, Weiping
2016-02-01
Calcium polyphosphate is a biodegradable bone substitute. It remains a challenge to prepare porous calcium polyphosphate with desired gradient porous structures. In this study, a modified one-step gravity sintering method was used to prepare calcium polyphosphate scaffolds with desired-gradient-pore-size distribution. The differences of porous structure, mechanical strength, and degradation rate between gradient and homogenous calcium polyphosphate scaffolds were evaluated by micro-computed tomography, scanning electron microscopy, and mechanical testing. Preosteoblastic MC3T3-E1 cells were seeded onto gradient and homogenous calcium polyphosphate scaffolds and cultured in a flow perfusion bioreactor. The distribution, proliferation, and differentiation of the MC3T3-E1 cells were compared to that of homogenous calcium polyphosphate scaffolds. Though no significant difference of cell proliferation was found between the gradient and the homogenous calcium polyphosphate scaffolds, a much higher cell differentiation and mineralization were observed in the gradient calcium polyphosphate scaffolds than that of the homogenous calcium polyphosphate scaffolds, as manifested by increased alkaline phosphatase activity (p < 0.05). The improved distribution and differentiation of cultured cells within gradient scaffolds were further supported by both (18)F-fluorine micro-positron emission tomography scanning and in vitro tetracycline labeling. We conclude that the calcium polyphosphate scaffold with gradient pore sizes enhances osteogenic cell differentiation as well as mineralization. The in vivo performance of gradient calcium polyphosphate scaffolds warrants further investigation in animal bone defect models. © The Author(s) 2015.
Lacruz, Rodrigo S; Smith, Charles E; Bringas, Pablo; Chen, Yi-Bu; Smith, Susan M; Snead, Malcolm L; Kurtz, Ira; Hacia, Joseph G; Hubbard, Michael J; Paine, Michael L
2012-05-01
The gene repertoire regulating vertebrate biomineralization is poorly understood. Dental enamel, the most highly mineralized tissue in mammals, differs from other calcifying systems in that the formative cells (ameloblasts) lack remodeling activity and largely degrade and resorb the initial extracellular matrix. Enamel mineralization requires that ameloblasts undergo a profound functional switch from matrix-secreting to maturational (calcium transport, protein resorption) roles as mineralization progresses. During the maturation stage, extracellular pH decreases markedly, placing high demands on ameloblasts to regulate acidic environments present around the growing hydroxyapatite crystals. To identify the genetic events driving enamel mineralization, we conducted genome-wide transcript profiling of the developing enamel organ from rat incisors and highlight over 300 genes differentially expressed during maturation. Using multiple bioinformatics analyses, we identified groups of maturation-associated genes whose functions are linked to key mineralization processes including pH regulation, calcium handling, and matrix turnover. Subsequent qPCR and Western blot analyses revealed that a number of solute carrier (SLC) gene family members were up-regulated during maturation, including the novel protein Slc24a4 involved in calcium handling as well as other proteins of similar function (Stim1). By providing the first global overview of the cellular machinery required for enamel maturation, this study provide a strong foundation for improving basic understanding of biomineralization and its practical applications in healthcare. Copyright © 2011 Wiley Periodicals, Inc.
Synthesis of calcium vanadate minerals and related compounds
Marvin, Richard F.
1956-01-01
Synthesis of natural vanadates shows that most of them are stable in an acid environment. Phase studies of a portion of the system CaO-V2O5-H2O indicate that calcium vanadates are an indicator of environmental pH conditions. Some minerals, such as pascoute, indicate rapid evaporation of vanadite solutions; other minerals, such as hewettite, show that slow evaporation took place. Cursory examination of systems K2O-UO2-(NO3)2-V2O5 and CaO-UO2(NO3)2-V2O5, both in aqueous solution, has yielded information on the relationships among carnotite, tyuyamunite, and rauvite.
A systematic study of multiple minerals precipitation modelling in wastewater treatment.
Kazadi Mbamba, Christian; Tait, Stephan; Flores-Alsina, Xavier; Batstone, Damien J
2015-11-15
Mineral solids precipitation is important in wastewater treatment. However approaches to minerals precipitation modelling are varied, often empirical, and mostly focused on single precipitate classes. A common approach, applicable to multi-species precipitates, is needed to integrate into existing wastewater treatment models. The present study systematically tested a semi-mechanistic modelling approach, using various experimental platforms with multiple minerals precipitation. Experiments included dynamic titration with addition of sodium hydroxide to synthetic wastewater, and aeration to progressively increase pH and induce precipitation in real piggery digestate and sewage sludge digestate. The model approach consisted of an equilibrium part for aqueous phase reactions and a kinetic part for minerals precipitation. The model was fitted to dissolved calcium, magnesium, total inorganic carbon and phosphate. Results indicated that precipitation was dominated by the mineral struvite, forming together with varied and minor amounts of calcium phosphate and calcium carbonate. The model approach was noted to have the advantage of requiring a minimal number of fitted parameters, so the model was readily identifiable. Kinetic rate coefficients, which were statistically fitted, were generally in the range 0.35-11.6 h(-1) with confidence intervals of 10-80% relative. Confidence regions for the kinetic rate coefficients were often asymmetric with model-data residuals increasing more gradually with larger coefficient values. This suggests that a large kinetic coefficient could be used when actual measured data is lacking for a particular precipitate-matrix combination. Correlation between the kinetic rate coefficients of different minerals was low, indicating that parameter values for individual minerals could be independently fitted (keeping all other model parameters constant). Implementation was therefore relatively flexible, and would be readily expandable to include other minerals. Copyright © 2015 Elsevier Ltd. All rights reserved.
Antioxidant mechanism of milk mineral-high-affinity iron binding.
Allen, K; Cornforth, D
2007-01-01
Milk mineral (MM), a by-product of whey processing, is an effective antioxidant in meat systems, but the antioxidant mechanism has not been established. MM has been postulated to chelate iron and prevent iron-catalysis of lipid oxidation. The objective of this research was to examine this putative mechanism. MM was compared to sodium tripolyphosphate (STPP), calcium phosphate monobasic (CPM), and calcium pyrophosphate (CPP) to determine iron-binding capacity, sample solubility, and eluate soluble phosphorus after treating samples with a ferrous chloride standard. Scanning electron microscopy with energy-dispersive X-ray analysis was used to localize minerals on iron-treated MM particle surfaces. Histochemical staining for calcium was performed on raw and cooked ground beef samples with added MM. MM bound more iron per gram (P < 0.05) than the other compounds, and was much less soluble (P < 0.05) than either STPP or CPM. Mineral localization showed an even distribution of calcium, phosphorus, oxygen, and iron across the MM particle surface, directly demonstrating iron binding to MM particles. Unlike other common chelating agents, such as STPP and citrate, histochemical staining demonstrated that MM remained insoluble in ground beef, even after cooking. The ability of MM to bind iron and remain insoluble may enhance its antioxidant effect by removing iron ions from solution. However, MM particles must be small and well distributed in order to adequately bind iron throughout the food system.
The influence of scale inhibitors on calcium oxalate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gill, J.S.
1999-11-01
Precipitation of calcium oxalate is a common occurrence in mammalian urinary tract deposits and in various industrial processes such as paper making, brewery fermentation, sugar evaporation, and tannin concentration. Between pH 3.5 to 4.5 the driving force for calcium oxalate precipitation increases almost by three fold. It is a complicated process to predict both the nature of a deposit and at which stage of a multi-effect evaporator a particular mineral will deposit, as this depends on temperature, pH, total solids, and kinetics of mineralization. It is quite a challenge to inhibit calcium oxalate precipitation in the pH range of 4--6.more » Al{sup 3+} ions provide excellent threshold inhibition in this pH range and can be used to augment traditional inhibitors such as polyphosphates and polycarboxylates.« less
Garg, A; Bonanome, A; Grundy, S M; Unger, R H; Breslau, N A; Pak, C Y
1990-04-01
Transient hypercalciuria has been noted after high carbohydrate meals which is independent of dietary calcium and is probably due to impaired renal calcium reabsorption mediated by an increase in plasma insulin levels. Based on these observations, some investigators believe that long term intake of high carbohydrate diets may increase the risk of nephrolithiasis and possibly osteoporosis. Using a randomized cross-over design, we compared high carbohydrate diets (60% carbohydrate and 25% fat) with high fat diets (50% fat and 35% carbohydrate) for effects on metabolism of calcium and other minerals in eight normal subjects and eight euglycemic patients with noninsulin-dependent diabetes mellitus. All other dietary constituents, such as protein, fiber, fluid, minerals (including Ca, Mg, Na, K, and P), and caffeine intake, were kept constant. Despite higher daylong levels of plasma insulin on the high carbohydrate diets compared to the high fat diet in both normal and noninsulin-dependent diabetic subjects, no changes in daily urinary excretion of calcium or other constituents, associated with renal stone risk, were observed. Furthermore, there was no change in fractional intestinal 47Ca absorption. Although hypercalciuria may ensue transiently after high carbohydrate meals, we conclude that substitution of simple or complex carbohydrates for fats in an isocaloric manner for a longer duration does not result in significant urinary calcium loss, and therefore, high intakes of digestible carbohydrates may not increase the risk of nephrolithiasis or osteoporosis via this mechanism.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-30
... Register on July 1, 2010 (75 FR 38142). The workers produced precipitated calcium carbonate used in the... precipitated calcium carbonate from the subject firm to a foreign country; nor was there any increase in imports of articles like or directly competitive with precipitated calcium carbonate produced at the...
Yang, Mingying; Mandal, Namita; Shuai, Yajun; Zhou, Guanshan; Min, Sijia; Zhu, Liangjun
2014-01-01
This study aimed to investigate the mineralization of Antheraea pernyi (A. pernyi) silk sericin. Mineralization of A. pernyi sericin was performed by alternative soaking in calcium and phosphate. The inhibition of precipitation of calcium carbonate and von Kossa staining on A. pernyi sericin were tested, and the corresponding results prove that A. pernyi sericin has Ca binding activity. Scanning electron microscope (SEM) observation shows that spherical crystals could be nucleated on the A. pernyi sericin film. These crystals were confirmed to be hydroxyapatite according to FT-IR and XRD spectra, indicating that A. pernyi sericin is capable of mineralization. In addition, cell adhesion and growth activity assay demonstrate that A. pernyi sericin shows excellent biocompatibility for the growth of MG-63 cells.
Increased vertebral bone mineral in response to reduced exercise in amenorrheic runners.
Lindberg, J S; Powell, M R; Hunt, M M; Ducey, D E; Wade, C E
1987-01-01
Seven female runners found to have exercise-induced amenorrhea and decreased bone mineral were reevaluated after 15 months. During the 15-month period, four runners took supplemental calcium and reduced their weekly running distance by 43%, resulting in an average 5% increase in body weight, increased estradiol levels and eumenorrhea. Bone mineral content increased from 1.003+/-0.097 to 1.070+/-0.089 grams per cm.(2) Three runners continued to have amenorrhea, with no change in running distance or body weight. Estradiol levels remained abnormally low and there was no significant change in the bone mineral content, although all three took supplemental calcium. We found that early osteopenia associated with exercise-induced menstrual dysfunction improved when runners reduced their running distance, gained weight and became eumenorrheic.
Cao, Yong; Miao, Jianyin; Liu, Guo; Luo, Zhen; Xia, Zumeng; Liu, Fei; Yao, Mingfei; Cao, Xiaoqiong; Sun, Shengwei; Lin, Yanyin; Lan, Yaqi; Xiao, Hang
2017-03-22
The ability of casein phosphopeptides (CPPs) to bind and transport minerals has been previously studied. However, the single bioactive peptides responsible for the effects of CPPs have not been identified. This study was to purify calcium-binding peptides from CPPs and to determine their effects on calcium and magnesium uptake by Caco-2 cell monolayers. Five monomer peptides designated P1 to P5 were isolated and the amino acid sequences were determined using LC-MS/MS. Compared with the CPP-free control, all five monomeric peptides exhibited significant enhancing effects on the uptake of calcium and magnesium (P < 0.05). Interestingly, when calcium and magnesium were presented simultaneously with P5, magnesium was taken up with priority over calcium in the Caco-2 cell monolayers. For example, at 180 min, the amount of transferred magnesium and calcium was 78.4 ± 0.95 μg/well and 2.56 ± 0.64 μg/well, respectively, showing a more than 30-fold difference in the amount of transport caused by P5. These results provide novel insight into the mineral transport activity of phosphopeptides obtained from casein.
NASA Technical Reports Server (NTRS)
Morgan, J. L. L.; Skulan, J. L.; Gordon, G. E.; Smith, Scott M.; Romaniello, S. J.; Anbar, A. D.
2012-01-01
Metabolic bone diseases like osteoporosis result from the disruption of normal bone mineral balance (BMB) resulting in bone loss. During spaceflight astronauts lose substantial bone. Bed rest provides an analog to simulate some of the effects of spaceflight; including bone and calcium loss and provides the opportunity to evaluate new methods to monitor BMB in healthy individuals undergoing environmentally induced-bone loss. Previous research showed that natural variations in the Ca isotope ratio occur because bone formation depletes soft tissue of light Ca isotopes while bone resorption releases that isotopically light Ca back into soft tissue (Skulan et al, 2007). Using a bed rest model, we demonstrate that the Ca isotope ratio of urine shifts in a direction consistent with bone loss after just 7 days of bed rest, long before detectable changes in bone mineral density (BMD) occur. The Ca isotope variations tracks changes observed in urinary N-teleopeptide, a bone resorption biomarker. Bone specific alkaline phosphatase, a bone formation biomarker, is unchanged. The established relationship between Ca isotopes and BMB can be used to quantitatively translate the changes in the Ca isotope ratio to changes in BMD using a simple mathematical model. This model predicts that subjects lost 0.25 0.07% ( SD) of their bone mass from day 7 to day 30 of bed rest. Given the rapid signal observed using Ca isotope measurements and the potential to quantitatively assess bone loss; this technique is well suited to study the short-term dynamics of bone metabolism.
Elmaataoui, A; Elmachtani Idrissi, S; Dami, A; Bouhsain, S; Chabraoui, L; Ouzzif, Z
2014-02-01
The aim of the study is to find the correlation between bone turnover markers and bone mineral density in a cohort of Moroccan postmenopausal women. A cross-sectional study, conducted over a period of 12 months from October 2008 to November 2009. Five hundred Moroccan postmenopausal women volunteers participated in this study and we included only 185. In this cohort of 185 women, average age 60 years, the percentage of osteoporotic women was 35.7%, they were older 62.09 (9.13) years and they had an average of the body mass index (BMI), the lowest 29.58 (4.45). The values of the bone mineral density (BMD) measured at the lumbar spine correlated positively and significantly with BMI (P<0.001), serum calcium (P=0.026), negatively with age (P<0.001) and osteocalcin (OC) (P=0.0033). As for the results of BMD measured at the femoral neck, they show a negative and highly significant correlation with age (P<0.001) and osteocalcin. Looking for an association between the biochemical markers of bone remodeling, a weak positive correlation was found between the calcium (Ca) and alkaline phosphatase (PAL) on the one hand and Ca and intact parathyroid hormone (PTHi) in the other hand. And a significant positive correlation was found between PTHi and PAL, and between PTHi and OC. Finally, a significant positive correlation was found between the cross-laps (β-CTX) and Ca and between PAL and OC. Our results are in agree to some international studies and disagree to others. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Steckling, S de M; Ribeiro, N D; Arns, F D; Mezzomo, H C; Possobom, M T D F
2017-03-22
The development of common bean cultivars with high technological quality that are biofortified with minerals, is required to meet the demand for food with health benefits. The objectives of this study were to evaluate whether common bean genotypes differ in terms of technological and mineral biofortification traits, to study the correlations between these characters, to analyze the genetic dissimilarity of common bean genotypes, and to select superior lines for these traits. For this, 14 common bean genotypes were evaluated in experiments conducted in three growing seasons in the Rio Grande do Sul State, Brazil. A significant genotype x environment interaction was observed for technological quality (mass of 100 grains and cooking time) and biofortification traits (concentration of potassium, phosphorus, calcium, iron, zinc, and copper). Positive correlation estimates were obtained between phosphorus and potassium (r = 0.575), iron and zinc (r = 0.641), copper and iron (r = 0.729), and copper and phosphorus (r = 0.533). In the main component cluster analysis, four groups of genotypes were formed. The following lines are recommended for selection: LP 11-363 for fast-cooking, CNFC 11 948 for high iron concentration, and LEC 03-14 for high potassium, phosphorus, and calcium concentrations in grains. Common bean lines with high phosphorus and iron concentrations in grains can be indirectly selected based on higher potassium, copper, and zinc concentrations. Controlled crossings between LP 11-363 x CNFC 11 948 and LP 11-363 x LEC 03-14 are recommended to obtain segregating lines that are fast-cooking and biofortified with minerals.
Oliveira, Marta; Ramos, Sandra; Delerue-Matos, Cristina; Morais, Simone
2015-06-15
Espresso coffee beverages prepared from pure origin roasted ground coffees from the major world growing regions (Brazil, Ethiopia, Colombia, India, Mexico, Honduras, Guatemala, Papua New Guinea, Kenya, Cuba, Timor, Mussulo and China) were characterized and compared in terms of their mineral content. Regular consumption of one cup of espresso contributes to a daily mineral intake varying from 0.002% (sodium; Central America) to 8.73% (potassium; Asia). The mineral profiles of the espresso beverages revealed significant inter- and intra-continental differences. South American pure origin coffees are on average richer in the analyzed elements except for calcium, while samples from Central America have generally lower mineral amounts (except for manganese). Manganese displayed significant differences (p<0.05) among the countries of each characterized continent. Intercontinental and inter-country discrimination between the major world coffee producers were achieved by applying canonical discriminant analysis. Manganese and calcium were found to be the best chemical descriptors for origin. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chain, Amina; Koury, Josely C; Bezerra, Flávia Fioruci
2012-09-01
Severe bone loss is a recognized complication of chronic spinal cord injury (SCI). Physical exercise contributes to bone health; however, its influence on bone mass of cervical SCI individuals has not been investigated. The aim of this study was to investigate the influence of physical activity on bone mass, bone metabolism, and vitamin D status in quadriplegics. Total, lumbar spine (L1-L4), femur and radius bone mineral density (BMD) were assessed in active (n = 15) and sedentary (n = 10) quadriplegic men by dual energy X-ray absorptiometry. Concentrations of 25-hydroxyvitamin D [25(OH)D], PTH, IGF1, osteocalcin and NTx were measured in serum. After adjustments for duration of injury, total body mass, and habitual calcium intake, bone indices were similar between groups, except for L1-L4 BMD Z score that was higher in the sedentary group (P < 0.05). Hours of physical exercise per week correlated positively with 25(OH)D (r = 0.59; P < 0.05) and negatively with PTH (r = -0.50; P < 0.05). Femur BMD was negatively associated with the number of months elapsed between the injury and the onset of physical activity (r = -0.60; P < 0.05). Moreover, in the active subjects, both L1-L4 BMD Z score (r = 0.72; P < 0.01) and radius BMD (r = 0.59; P < 0.05) were positively associated with calcium intake. In this cross-sectional study, both the onset of physical activity after injury and the number of hours dedicated to exercise were able to influence bone density and bone-related hormones in quadriplegic men. Our results also suggest a positive combined effect of exercise and calcium intake on bone health of quadriplegic individuals.
Reloading partly recovers bone mineral density and mechanical properties in hind limb unloaded rats
NASA Astrophysics Data System (ADS)
Zhao, Fan; Li, Dijie; Arfat, Yasir; Chen, Zhihao; Liu, Zonglin; Lin, Yu; Ding, Chong; Sun, Yulong; Hu, Lifang; Shang, Peng; Qian, Airong
2014-12-01
Skeletal unloading results in decreased bone formation and bone mass. During long-term space flight, the decreased bone mass is impossible to fully recover. Therefore, it is necessary to develop the effective countermeasures to prevent spaceflight-induced bone loss. Hindlimb Unloading (HLU) simulates effects of weightlessness and is utilized extensively to examine the response of musculoskeletal systems to certain aspects of space flight. The purpose of this study is to investigate the effects of a 4-week HLU in rats and subsequent reloading on the bone mineral density (BMD) and mechanical properties of load-bearing bones. After HLU for 4 weeks, the rats were then subjected to reloading for 1 week, 2 weeks and 3 weeks, and then the BMD of the femur, tibia and lumbar spine in rats were assessed by dual energy X-ray absorptiometry (DXA) every week. The mechanical properties of the femur were determined by three-point bending test. Dry bone and bone ash of femur were obtained through Oven-Drying method and were weighed respectively. Serum alkaline phosphatase (ALP) and serum calcium were examined through ELISA and Atomic Absorption Spectrometry. The results showed that 4 weeks of HLU significantly decreased body weight of rats and reloading for 1 week, 2 weeks or 3 weeks did not recover the weight loss induced by HLU. However, after 2 weeks of reloading, BMD of femur and tibia of HLU rats partly recovered (+10.4%, +2.3%). After 3 weeks of reloading, the reduction of BMD, energy absorption, bone mass and mechanical properties of bone induced by HLU recovered to some extent. The changes in serum ALP and serum calcium induced by HLU were also recovered after reloading. Our results indicate that a short period of reloading could not completely recover bone after a period of unloading, thus some interventions such as mechanical vibration or pharmaceuticals are necessary to help bone recovery.
Fifty years of human space travel: implications for bone and calcium research.
Smith, S M; Abrams, S A; Davis-Street, J E; Heer, M; O'Brien, K O; Wastney, M E; Zwart, S R
2014-01-01
Calcium and bone metabolism remain key concerns for space travelers, and ground-based models of space flight have provided a vast literature to complement the smaller set of reports from flight studies. Increased bone resorption and largely unchanged bone formation result in the loss of calcium and bone mineral during space flight, which alters the endocrine regulation of calcium metabolism. Physical, pharmacologic, and nutritional means have been used to counteract these changes. In 2012, heavy resistance exercise plus good nutritional and vitamin D status were demonstrated to reduce loss of bone mineral density on long-duration International Space Station missions. Uncertainty continues to exist, however, as to whether the bone is as strong after flight as it was before flight and whether nutritional and exercise prescriptions can be optimized during space flight. Findings from these studies not only will help future space explorers but also will broaden our understanding of the regulation of bone and calcium homeostasis on Earth.
Bianchi, Maria Luisa; Colombo, Carla; Assael, Baroukh M; Dubini, Antonella; Lombardo, Mariangela; Quattrucci, Serena; Bella, Sergio; Collura, Mirella; Messore, Barbara; Raia, Valeria; Poli, Furio; Bini, Rita; Albanese, Carlina V; De Rose, Virginia; Costantini, Diana; Romano, Giovanna; Pustorino, Elena; Magazzù, Giuseppe; Bertasi, Serenella; Lucidi, Vincenzina; Traverso, Gabriella; Coruzzo, Anna; Grzejdziak, Amelia D
2013-07-01
Long-term complications of cystic fibrosis include osteoporosis and fragility fractures, but few data are available about effective treatment strategies, especially in young patients. We investigated treatment of low bone mineral density in children, adolescents, and young adults with cystic fibrosis. We did a multicentre trial in two phases. We enrolled patients aged 5-30 years with cystic fibrosis and low bone mineral density, from ten cystic fibrosis regional centres in Italy. The first phase was an open-label, 12-month observational study of the effect of adequate calcium intake plus calcifediol. The second phase was a 12-month, double-blind, randomised, placebo-controlled, parallel group study of the efficacy and safety of oral alendronate in patients whose bone mineral apparent density had not increased by 5% or more by the end of the observational phase. Patients were randomly assigned to either alendronate or placebo. Both patients and investigators were masked to treatment assignment. We used dual x-ray absorptiometry at baseline and every 6 months thereafter, corrected for body size, to assess lumbar spine bone mineral apparent density. We assessed bone turnover markers and other laboratory parameters every 3-6 months. The primary endpoint was mean increase of lumbar spine bone mineral apparent density, assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT01812551. We screened 540 patients and enrolled 171 (mean age 13·8 years, SD 5·9, range 5-30). In the observational phase, treatment with calcium and calcifediol increased bone mineral apparent density by 5% or more in 43 patients (25%). 128 patients entered the randomised phase. Bone mineral apparent density increased by 16·3% in the alendronate group (n=65) versus 3·1% in the placebo group (n=63; p=0·0010). 19 of 57 young people (33·3%) receiving alendronate attained a normal-for-age bone mineral apparent density Z score. In the observational phase, five patients had moderate episodes of hypercalciuria, which resolved after short interruption of calcifediol treatment. During the randomised phase, one patient taking alendronate had mild fever versus none in the placebo group; treatment groups did not differ significantly for other adverse events. Correct calcium intake plus calcifediol can improve bone mineral density in some young patients with cystic fibrosis. In those who do not respond to calcium and calcifediol alone, alendronate can safely and effectively increase bone mineral density. Telethon Foundation (Italy). Copyright © 2013 Elsevier Ltd. All rights reserved.
Shin, Hyehyung; Liu, Pei-Yang; Panton, Lynn B; Ilich, Jasminka Z
2014-01-01
Diminished physical performance can be detrimental among the older adults, causing falls and subsequent fractures, loss of independence, and increased morbidity and mortality rates. Therefore, it is important to maintain functional ability from the early onset of aging. The purpose of this study was to investigate the relationship between physical performance measures and body composition (bone, fat, and lean mass) in healthy, overweight and obese, early postmenopausal white women. A total of 97 participants aged 56.0 (4.4) years (mean (SD)) with body mass index of 31.0 (4.6) kg/m(2) were included. Weight and height were recorded and 3 days of dietary records and physical activity were collected. Dual-energy x-ray absorptiometry measurements for body composition and bone mineral density were performed. Fasting blood samples were used for serum 25-hydroxy vitamin D (25OHD) analysis. Measures of physical performance included handgrip strength, 8-meter walking speed, one-leg-stance time, 8-foot Timed Get-Up-and-Go Test, and chair sit-to-stand test. Results showed that higher lean mass was related to better physical performance on items assessing body strength, including handgrip (r ranged from 0.22 to 0.25, P < .05) while higher body fat was related to the poorer physical performance in each of the assessed measures. Bone mineral density of the forearm was positively related to the handgrip strength (r = 0.207, P < .05). In regression analyses (controlled for age, weight, height, serum 25OHD status, calcium intake, physical activity, and smoking), fat mass of the lower extremities was inversely related to walking speed, one-leg-stance time, and Get-Up-and-Go measures, all crucial for mobility (r(2) = 0.13-0.23, P < .05). Overall, higher fat and lower lean mass was related to poorer physical performance, while forearm bone mineral density was related to the handgrip strength only. Further investigation may be beneficial for a better understanding of how body composition may prevent decline in physical performance among overweight/obese, mid-age, and older women.
Mangano, Kelsey M; Walsh, Stephen J; Kenny, Anne M; Insogna, Karl L; Kerstetter, Jane E
2014-02-01
High dietary acid load (DAL) may be detrimental to bone mineral density (BMD). The objectives of the study were to: (1) evaluate the cross-sectional relation between DAL and BMD; and (2) determine whether calcium intake modifies this association. Men (n = 1218) and women (n = 907) aged ≥60 years were included from the National Health and Nutrition Examination Survey 2005-2008. Nutrient intake from 2, 24-hour recalls was used to calculate net endogenous acid production (NEAP) and potential renal acid load (PRAL) (mEq/d). PRAL was calculated from dietary calcium (PRALdiet ) and diet + supplemental calcium (PRALtotal ). Tests for linear trend in adjusted mean BMD of the hip and lumbar spine were performed across energy-adjusted NEAP and PRAL quartiles. Modification by calcium intake (dietary or total) above or below 800 mg/d was assessed by interaction terms. Overall, mean age was 69 ± 0.3 years. Among women, there was no association between NEAP and BMD. PRALdiet was positively associated with proximal femur BMD (p trend = 0.04). No associations were observed with PRALtotal at any BMD site (p range, 0.38-0.82). Among men, no significant associations were observed between BMD and NEAP or PRAL. However, an interaction between PRALdiet and calcium intake was observed with proximal femur BMD (p = 0.08). An inverse association between PRALdiet and proximal femur BMD was detected among men with <800 mg/d dietary calcium (p = 0.02); no associations were found among men with ≥800 mg/d (p = 0.98). A significant interaction with PRALtotal was not observed. In conclusion, when supplemental calcium is considered, there is no association between DAL and BMD among adults. Men with low dietary calcium showed an inverse relation with PRAL at the proximal femur; in women no interaction was observed. This study highlights the importance of calcium intake in counteracting the adverse effect of DAL on bone health. Further research should determine the relation between DAL and change in BMD with very low calcium intake. © 2014 American Society for Bone and Mineral Research.
21 CFR 107.100 - Nutrient specifications.
Code of Federal Regulations, 2011 CFR
2011-04-01
... C (ascorbic acid) Milligrams 8 Choline 2 do 7 Inositol 2 do 4 Minerals Calcium do 60 Phosphorus do... prepared for consumption as directed on the container. (e) The ratio of calcium to phosphorus in infant...
21 CFR 107.100 - Nutrient specifications.
Code of Federal Regulations, 2010 CFR
2010-04-01
... C (ascorbic acid) Milligrams 8 Choline 2 do 7 Inositol 2 do 4 Minerals Calcium do 60 Phosphorus do... prepared for consumption as directed on the container. (e) The ratio of calcium to phosphorus in infant...
Chen, H-L; Tung, Y-T; Chuang, C-H; Tu, M-Y; Tsai, T-C; Chang, S-Y; Chen, C-M
2015-02-01
Kefir treatment in ovariectomized (OVX) rats could significantly decrease the levels of bone turnover markers and prevent OVX-induced bone loss, deterioration of trabecular microarchitecture, and biomechanical dysfunction that may be due to increase intracellular calcium uptake through the TRPV6 calcium channel. Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased fracture risk. The incidence of osteoporosis increases with age and occurs most frequently in postmenopausal women due to estrogen deficiency, as the balance between bone resorption and bone formation shifts towards increased levels of bone resorption. Among various methods of prevention and treatment for osteoporosis, an increase in calcium intake is the most commonly recommended preventive measure. Kefir is a fermented milk product made with kefir grains that degrade milk proteins into various peptides with health-promoting effects, including immunomodulating-, antithrombotic-, antimicrobial-, and calcium-absorption-enhancing bioactivities. The aim of this study is to investigate the effect of kefir on osteoporosis prophylaxis in an ovariectomized rat model. A total of 56 16-week-old female Sprague-Dawley (SD) rats were divided into 7 experimental groups: sham (normal), OVX/Mock, OVX/1X kefir (164 mg/kg BW/day), OVX/2X kefir (328 mg/kg BW/day), OVX/4X kefir (656 mg/kg BW/day), OVX/ALN (2.5 mg/kg BW/day), and OVX/REBONE (800 mg/kg BW/day). After 12-week treatment with kefir, the bone physiology in the OVX rat model was investigated. Accordingly, the aim of this study was to investigate the possible transport mechanism involved in calcium absorption using the Caco-2 human cell line. A 12-week treatment with kefir on the OVX-induced osteoporosis model reduced the levels of C-terminal telopeptides of type I collagen (CTx), bone turnover markers, and trabecular separation (Tb. Sp.). Additionally, treatment with kefir increased trabecular bone mineral density (BMD), bone volume (BV/TV), trabecular thickness (Tb. Th), trabecular number (Tb. N), and the biomechanical properties (hardness and modulus) of the distal femur with a dose-dependent efficacy. In addition, in in vitro assay, we found that kefir increased intracellular calcium uptake in Caco-2 cell through TRPV6 calcium channels and not through L-type voltage-operated calcium channels. The protective effect of kefir in the OVX rat model may occur through increasing intracellular calcium uptake through the TRPV6 calcium channel.
The mineral content of tap water in United States households
USDA-ARS?s Scientific Manuscript database
The composition of tap water contributes to dietary intake of minerals. The USDA’s Nutrient Data Laboratory (NDL) conducted a study of the mineral content of residential tap water, to generate current data for the USDA National Nutrient Database. Sodium, potassium, calcium, magnesium, iron, copper...
[Physicochemical quality of drinking water in Southern Algeria: study of excess mineral salts].
Djellouli, H M; Taleb, S; Harrache-Chettouh, D; Djaroud, S
2005-01-01
The aim of this study was to determine the physicochemical composition of water intended for human consumption in several regions of Southern Algeria. Excess minerals in drinking water, including magnesium, calcium, sulfates and fluorides play a fundamental role in the prevention of urinary calculi, which are formed mainly from calcium oxalate. The ever-increasingly prevalence of this disorder and its recurrence make it a real public health problem in Algeria. The most elementary preventive treatment, recommended to all subjects with lithiasis, is to drink 2 to 3 L water distributed throughout the (24-hour) day. This study began by conducting a physicochemical analysis of the principal components of water from several sources. We will subsequently test it to examine the effects of its mineral salts on the crystallization kinetics of the principal component of calculi (calcium oxalate). The results indicate that 77.5 % of the samples had magnesium concentrations ([Mg 2+] > 50 mg/L), 95 % were sulfated, with sulfate ion concentrations exceeding the standard recommended by WHO ([SO4 2-] > 250 mg/L). Moreover, 57.5 % had excess fluoride levels, [F-] > 1.5 mg/L, and 65 % excessive calcium concentrations, with Ca 2+ > 150 mg/L.
Magnesium-aspartate-based crystallization switch inspired from shell molt of crustacean
Tao, Jinhui; Zhou, Dongming; Zhang, Zhisen; Xu, Xurong; Tang, Ruikang
2009-01-01
Many animals such as crustacean periodically undergo cyclic molt of the exoskeleton. During this process, amorphous calcium mineral phases are biologically stabilized by magnesium and are reserved for the subsequent rapid formation of new shell tissue. However, it is a mystery how living organisms can regulate the transition of the precursor phases precisely. We reveal that the shell mineralization from the magnesium stabilized precursors is associated with the presence of Asp-rich proteins. It is suggested that a cooperative effect of magnesium and Asp-rich compound can result into a crystallization switch in biomineralization. Our in vitro experiments confirm that magnesium increases the lifetime of amorphous calcium carbonate and calcium phosphate in solution so that the crystallization can be temporarily switched off. Although Asp monomer alone inhibits the crystallization of pure amorphous calcium minerals, it actually reduces the stability of the magnesium-stabilized precursors to switch on the transformation from the amorphous to crystallized phases. These modification effects on crystallization kinetics can be understood by an Asp-enhanced magnesium desolvation model. The interesting magnesium-Asp-based switch is a biologically inspired lesson from nature, which can be developed into an advanced strategy to control material fabrications. PMID:20007788
Magnesium-aspartate-based crystallization switch inspired from shell molt of crustacean.
Tao, Jinhui; Zhou, Dongming; Zhang, Zhisen; Xu, Xurong; Tang, Ruikang
2009-12-29
Many animals such as crustacean periodically undergo cyclic molt of the exoskeleton. During this process, amorphous calcium mineral phases are biologically stabilized by magnesium and are reserved for the subsequent rapid formation of new shell tissue. However, it is a mystery how living organisms can regulate the transition of the precursor phases precisely. We reveal that the shell mineralization from the magnesium stabilized precursors is associated with the presence of Asp-rich proteins. It is suggested that a cooperative effect of magnesium and Asp-rich compound can result into a crystallization switch in biomineralization. Our in vitro experiments confirm that magnesium increases the lifetime of amorphous calcium carbonate and calcium phosphate in solution so that the crystallization can be temporarily switched off. Although Asp monomer alone inhibits the crystallization of pure amorphous calcium minerals, it actually reduces the stability of the magnesium-stabilized precursors to switch on the transformation from the amorphous to crystallized phases. These modification effects on crystallization kinetics can be understood by an Asp-enhanced magnesium desolvation model. The interesting magnesium-Asp-based switch is a biologically inspired lesson from nature, which can be developed into an advanced strategy to control material fabrications.
Peptoid nanosheets as soluble, two-dimensional templates for calcium carbonate mineralization.
Jun, Joo Myung V; Altoe, M Virginia P; Aloni, Shaul; Zuckermann, Ronald N
2015-06-25
Nacre-mimetic materials are of great interest, but difficult to synthesize, because they require the ordering of organic and inorganic materials on several length scales. Here we introduce peptoid nanosheets as a versatile two-dimensional platform to develop nacre mimetic materials. Free-floating zwitterionic nanosheets were mineralized with thin films of amorphous calcium carbonate (of 2-20 nm thickness) on their surface to produce planar nacre synthons. These can serve as tunable building blocks to produce layered brick and mortar nanoarchitectures.
Suntornsaratoon, Panan; Charoenphandhu, Narattaphol; Krishnamra, Nateetip
2018-03-01
Breastfeeding leads to bone calcium loss for milk production, resulting in progressive maternal osteopenia. Calcium supplement from natural sources has been postulated to be more beneficial to bone health than purified CaCO 3 because natural sources also contain other nutrients such as certain amino acids that might enhance calcium metabolism. Herein, we examined the effect of calcium supplementation from tuna bone powder and CaCO 3 on bones of dams and the offspring. Both forms of calcium supplement, i.e. tuna bone powder and CaCO 3 , increased maternal bone mineral density (BMD). However, bone histomorphometry revealed that only tuna bone had beneficial effect on maternal bone microstructure, i.e. increased bone formation, decreased bone resorption and increased in bone volume. Regarding the mechanical properties, the decreased ultimate load in non-supplement lactating mothers was restored to the load seen in nulliparous animals by calcium supplementation. Moreover, both tuna bone and CaCO 3 supplementation in mothers led to increased milk calcium concentration and consequently increased BMD in the growing offspring. Calcium supplement from tuna bone powder was effective in preventing maternal osteopenia. Tuna bone, which is a readily available fishing industrial waste, is a good alternative source of calcium supplement that increases BMD in both lactating mothers and the neonates. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
JUGDAOHSINGH, R.
2009-01-01
Low bone mass (osteoporosis) is a silent epidemic of the 21st century, which presently in the UK results in over 200,000 fractures annually at a cost of over one billion pounds. Figures are set to increase worldwide. Understanding the factors which affect bone metabolism is thus of primary importance in order to establish preventative measures or treatments for this condition. Nutrition is an important determinant of bone health, but the effects of the individual nutrients and minerals, other than calcium, is little understood. Accumulating evidence over the last 30 years strongly suggest that dietary silicon is beneficial to bone and connective tissue health and we recently reported strong positive associations between dietary Si intake and bone mineral density in US and UK cohorts. The exact biological role(s) of silicon in bone health is still not clear, although a number of possible mechanisms have been suggested, including the synthesis of collagen and/or its stabilization, and matrix mineralization. This review gives an overview of this naturally occurring dietary element, its metabolism and the evidence of its potential role in bone health. PMID:17435952
Micro-CT X-ray imaging exposes structured diffusion barriers within biofilms.
Keren-Paz, Alona; Brumfeld, Vlad; Oppenheimer-Shaanan, Yaara; Kolodkin-Gal, Ilana
2018-01-01
In nature, bacteria predominantly exist as highly structured biofilms, which are held together by extracellular polymeric substance and protect their residents from environmental insults, such as antibiotics. The mechanisms supporting this phenotypic resistance are poorly understood. Recently, we identified a new mechanism maintaining biofilms - an active production of calcite minerals. In this work, a high-resolution and robust µCT technique is used to study the mineralized areas within intact bacterial biofilms. µCT is a vital tool for visualizing bacterial communities that can provide insights into the relationship between bacterial biofilm structure and function. Our results imply that dense and structured calcium carbonate lamina forms a diffusion barrier sheltering the inner cell mass of the biofilm colony. Therefore, µCT can be employed in clinical settings to predict the permeability of the biofilms. It is demonstrated that chemical interference with urease, a key enzyme in biomineralization, inhibits the assembly of complex bacterial structures, prevents the formation of mineral diffusion barriers and increases biofilm permeability. Therefore, biomineralization enzymes emerge as novel therapeutic targets for highly resistant infections.
Althaf Hussain, Shaik; Kareem, Mohammed Abdul; Rasool, Shaik Nayab; Al Omar, Suliman Yousef; Saleh, Alwasel; Al-Fwuaires, Manal Abdulrahman; Daddam, Jayasimha Rayalu; Devi, Kodidhela Lakshmi
2018-01-01
The trace elements and minerals in Terminalia pallida fruit ethanolic extract (TpFE) were determined by the instrument inductively coupled plasma-mass spectrometry (ICP-MS), and the cardioprotection of TpFE against isoproterenol (ISO)-administered rats was studied. Rats were pretreated with TpFE (100, 300, and 500 mg/kg bw) for 30 days, with concurrent administration of ISO (85 mg/kg bw) for two consecutive days. The levels of trace elements and minerals in TpFE were below the permitted limits of World Health Organization standards. ISO administration significantly increased the heart weight and cardiac marker enzymes in serum, xanthine oxidase, sodium, and calcium in the heart, whereas significantly decreased body weight, reduced glutathione, glutathione-S-transferase, superoxide dismutase, and potassium in the heart. Oral pretreatment of TpFE significantly prevented the ISO-induced alterations. This is the first report that revealed the determination of trace elements and mineral nutrients of TpFE by ICP-MS which plays a principal role in the herbal drug discovery for the treatment of cardiovascular diseases.
Osteopenia and osteoporosis in people living with HIV: multiprofessional approach
Lima, Ana Lucia Lei Munhoz; de Oliveira, Priscila Rosalba D; Plapler, Perola Grimberg; Marcolino, Flora Maria D Andrea; de Souza Meirelles, Eduardo; Sugawara, André; Gobbi, Riccardo Gomes; dos Santos, Alexandre Leme Godoy; Camanho, Gilberto Luis
2011-01-01
Increasing bone mineralization abnormalities observed among people living with HIV (PLWHIV) result from various factors relating to the host, the virus, and the antiretrovirals used. Today, HIV infection is considered to be a risk factor for bone mineralization disorders. The test most recommended for diagnosing osteoporosis is measurement of bone mineral density by means of dual energy X-ray absorptiometry at two sites. Osteoporosis treatment has the aims of bone mass improvement and fracture control. A combination of calcium and vitamin D supplementation may reduce the risk of fractures. Antiresorptive drugs act by blocking osteoclastic activity and reducing bone remodeling. On the other hand, bone-forming drugs stimulate osteoblastogenesis, thereby stimulating the formation of bone matrix. Mixed-action medications are those that are capable of both stimulating bone formation and inhibiting reabsorption. Antiresorptive drugs form the group of medications with the greatest quantity of scientific evidence confirming their efficacy in osteoporosis treatment. Physical activity is a health promotion strategy for the general population, but only preliminary data on its real value and benefit among PLWHIV are available, especially in relation to osteoporosis. PMID:22267944
Osteopenia and osteoporosis in people living with HIV: multiprofessional approach.
Lima, Ana Lucia Lei Munhoz; de Oliveira, Priscila Rosalba D; Plapler, Perola Grimberg; Marcolino, Flora Maria D Andrea; de Souza Meirelles, Eduardo; Sugawara, André; Gobbi, Riccardo Gomes; Dos Santos, Alexandre Leme Godoy; Camanho, Gilberto Luis
2011-01-01
Increasing bone mineralization abnormalities observed among people living with HIV (PLWHIV) result from various factors relating to the host, the virus, and the antiretrovirals used. Today, HIV infection is considered to be a risk factor for bone mineralization disorders. The test most recommended for diagnosing osteoporosis is measurement of bone mineral density by means of dual energy X-ray absorptiometry at two sites. Osteoporosis treatment has the aims of bone mass improvement and fracture control. A combination of calcium and vitamin D supplementation may reduce the risk of fractures. Antiresorptive drugs act by blocking osteoclastic activity and reducing bone remodeling. On the other hand, bone-forming drugs stimulate osteoblastogenesis, thereby stimulating the formation of bone matrix. Mixed-action medications are those that are capable of both stimulating bone formation and inhibiting reabsorption. Antiresorptive drugs form the group of medications with the greatest quantity of scientific evidence confirming their efficacy in osteoporosis treatment. Physical activity is a health promotion strategy for the general population, but only preliminary data on its real value and benefit among PLWHIV are available, especially in relation to osteoporosis.
Weisinger, J R; Alonzo, E; Machado, C; Carlini, R; Martinis, R; Paz-Martínez, V; Bellorín-Font, E
1997-01-01
Previous studies from our laboratory demonstrated that bone mineral content is affected in patients with idiopathic hypercalciuria and that there is a correlation between bone mineral loss and in-vitro cytokine production. At the same time we found that short term treatment with alendronate decreased urinary calcium in these subjects. In the present study we have examined the long-term effects of alendronate treatment (10 mg/day for one year) on urinary calcium, urinary hydroxyproline and bone mineral content in 18 idiopathic hypercalciuric and 8 normocalciuric stone formers. Clinical characteristics, as well as gender and age distribution were similar in both groups. Urinary calcium and hydroxyproline, were measured monthly. Calcium excretion decreased significantly at the end of the first month, and remained lower thereafter (277 +/- 28, before vs. 202 +/- 26 mg/g creatinine, after 12 months on alendronate, p < 0.01). Urinary hydroxyproline decreased significantly during the study (125.5 +/- 32.1 vs. 39.66 +/- 17.5 mg/g creatinine, p < 0.05). Serum calcium, glomerular filtration rate, and urinary sodium, did not change during the study. Lumbar spine bone density (trabecular bone) obtained with X ray absorptiometry revealed a significant increase from 1.162 +/- 0.231 to 1.197 +/- 0.248 g/cm2 (p < 0.01). These changes were associated with a significant decrease in IL-1 alpha mRNA transcription by unstimulated and lipopolysaccharide stimulated blood mononuclear cells, as tested by the reverse transcriptase polymerase chain reaction. No changes were observed in bone cortical sites (femoral neck). Normocalciuric subjects showed no significant changes in urinary calcium. In summary, the changes observed in urinary calcium excretion and different bone metabolic parameters, suggest a role of bone in the pathophysiology of idiopathic hypercalciuria.
Physical activity programs for promoting bone mineralization and growth in preterm infants.
Schulzke, Sven M; Kaempfen, Siree; Trachsel, Daniel; Patole, Sanjay K
2014-04-22
Lack of physical stimulation may contribute to metabolic bone disease of preterm infants, resulting in poor bone mineralization and growth. Physical activity programs combined with adequate nutrition might help to promote bone mineralization and growth. The primary objective was to assess whether physical activity programs in preterm infants improve bone mineralization and growth and reduce the risk of fracture.The secondary objectives included other potential benefits in terms of length of hospital stay, skeletal deformities and neurodevelopmental outcomes, and adverse events.Subgroup analysis:• Given that the smallest infants are most vulnerable for developing osteopenia (Bishop 1999), a subgroup analysis was planned for infants with birth weight < 1000 g.• Calcium and phosphorus intake may affect an infant's ability to increase bone mineral content (Kuschel 2004). Therefore, an additional subgroup analysis was planned for infants receiving different amounts of calcium and phosphorus, along with full enteral feeds as follows. ∘ Below 100 mg/60 mg calcium/phosphorus or equal to/above 100 mg/60 mg calcium/phosphorus per 100 mL milk. ∘ Supplementation of calcium without phosphorus. ∘ Supplementation of phosphorus without calcium. The standard search strategy of the Cochrane Neonatal Review Group (CNRG) was used. The search included the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 9), MEDLINE, EMBASE, CINAHL (1966 to March 2013), and cross-references, as well as handsearching of abstracts of the Society for Pediatric Research and the International Journal of Sports Medicine. Randomized and quasi-randomized controlled trials comparing physical activity programs (extension and flexion, range-of-motion exercises) versus no organized physical activity programs in preterm infants. Data collection, study selection, and data analysis were performed according to the methods of the CNRG. Eleven trials enrolling 324 preterm infants (gestational age 26 to 34 weeks) were included in this review. All were small (N = 16 to 50) single-center studies that evaluated daily physical activity for three and one-half to eight weeks during initial hospitalization. Methodological quality and reporting of included trials were variable.Four trials demonstrated moderate short-term benefits of physical activity for bone mineralization at completion of the physical activity program. The only trial assessing long-term effects on bone mineralization showed no effect of physical activity administered during initial hospitalization on bone mineralization at 12 months corrected age. Meta-analysis from four trials demonstrated a positive effect of physical activity on daily weight gain (weighted mean difference (WMD) 2.21 g/kg/d, 95% confidence interval (CI) 1.23 to 3.19). Data from four trials showed a positive effect on linear growth (WMD 0.12 cm/wk, 95% CI 0.01 to 0.24) but not on head growth (WMD -0.03 cm/wk, 95% CI -0.14 to 0.08) during the study period. Only one trial reported on fractures (this outcome did not occur in intervention and control groups) and complications of preterm birth (no significant differences between intervention and control groups). None of the trials assessed other outcomes relevant to this review. Some evidence suggests that physical activity programs might promote short-term weight gain and bone mineralization in preterm infants. Data are inadequate to allow assessment of harm or long-term effects. Current evidence does not support the routine use of physical activity programs in preterm infants. Further trials incorporating infants with a high baseline risk of osteopenia are required. These trials should address adverse events, long-term outcomes, and the effects of nutritional intake (calories, protein, calcium, phosphorus).
Decreased water flowing from a forest amended with calcium silicate
Mark B. Green; Amey S. Bailey; Scott W. Bailey; John J. Battles; John L. Campbell; Charles T. Driscoll; Timothy J. Fahey; Lucie C. Lepine; Gene E. Likens; Scott V. Ollinger; Paul G. Schaberg
2013-01-01
Acid deposition during the 20th century caused widespread depletion of available soil calcium (Ca) throughout much of the industrialized world. To better understand how forest ecosystems respond to changes in a component of acidification stress, an 11.8-ha watershed was amended with wollastonite, a calcium silicate mineral, to restore available soil Ca to preindustrial...
Kingman, Joshua; Uitto, Jouni; Li, Qiaoli
2017-01-01
Generalized arterial calcification of infancy (GACI) is an autosomal recessive disorder caused by mutations in the ENPP1 gene. It is characterized by mineralization of the arterial blood vessels, often diagnosed prenatally, and associated with death in early childhood. There is no effective treatment for this devastating disorder. We previously characterized the Enpp1asjmutant mouse as a model of GACI, and we have now explored the effect of elevated dietary magnesium (five-fold) in pregnant mothers and continuing for the first 14 weeks of postnatal life. The mothers were kept on either control diet or experimental diet supplemented with magnesium. Upon weaning at 4 weeks of age the pups were placed either on control diet or high magnesium diet. The degree of mineralization was assessed at 14 weeks of age by histopathology and a chemical calcium assay in muzzle skin, kidney and aorta. Mice placed on high magnesium diet showed little, if any, evidence of mineralization when their corresponding mothers were also placed on diet enriched with magnesium during pregnancy and nursing. The reduced ectopic mineralization in these mice was accompanied by increased calcium and magnesium content in the urine, suggesting that magnesium competes calcium-phosphate binding thereby preventing the mineral deposition. These results have implications for dietary management of pregnancies in which the fetus is suspected of having GACI. Moreover, augmenting a diet with high magnesium may be beneficial for other ectopic mineralization diseases, including nephrocalcinosis. PMID:28402956
ERIC Educational Resources Information Center
Kaplan, Bonnie J.; Crawford, Susan G.; Field, Catherine J.; Simpson, J. Steven A.
2007-01-01
In this article, the authors explore the breadth and depth of published research linking dietary vitamins and minerals (micronutrients) to mood. Since the 1920s, there have been many studies on individual vitamins (especially B vitamins and Vitamins C, D, and E), minerals (calcium, chromium, iron, magnesium, zinc, and selenium), and vitamin-like…
Mineralogy and chemistry of urinary stones: patients from North Jordan.
Abboud, Iyad Ahmed
2008-10-01
Urinary stone diseases are increasing in the Middle East. The majority of urinary stone cases are found in the northern part of the country. Stone samples taken from patients living in the Irbid area were collected from Princess Basma Hospital. The present study concentrates on the mineralogical and chemical composition of the urinary stones and on the effective environmental factors that assist in developing the different types of urinary stones. Using X-ray diffraction techniques, the mineralogical composition of the urinary stones was found to be as follows: oxalate, cholesten, and uric acid, with cystine stones occuring more frequently than the others. Cholesten and calcium oxalate stones are the most dominant types of stones. Calcium oxalate is the most common type of oxalate stone. Calcium oxalate is represented in: whewellite, wheddellite, and calcium carbonate oxalate hydrate minerals, in addition to other minerals such as brushite, ammonium phosphate, vaterite, valleriite, and bobierrite from other types of stones. Bobierrite (phosphate group) is a new mineral reported in urinary stones, and this has not been determined in any previous study worldwide. Apatite (calcium phosphate) is deduced using scanning electron microscope (SEM) images. The SEM technique determined crystal forms and systems, shapes, morphological features, and the names of the minerals forming urine stones, while optical properties are studied by polarizing microscope. X-ray fluorescence technique determined the concentrations of major and some trace elements. It revealed that Ca is the main constituent of the urinary stones, especially those composed of calcium oxalate and calcium phosphate. The concentration of trace elements was Ba = 1.57, P = 3.61, Fe = 1.78, S = 2.08, Zr = 4.63, Mo = 3.92, Cu = 1.89, Co = 1.56, and F = 4.2% and was higher in the urinary stones of Jordanian patients than in foreigners in the country. Questionnaires completed by patients suggest that the most significant factors directly effecting the formation of stones are water, climate conditions, food rich in protein and rich in different chemicals. Moreover, some drugs and diseases might also help in developing other stones.
NASA Astrophysics Data System (ADS)
Bradley, D. A.; Muthuvelu, P.; Ellis, R. E.; Green, E. M.; Attenburrow, D.; Barrett, R.; Arkill, K.; Colridge, D. B.; Winlove, C. P.
2007-10-01
Bone is a dynamic structure, constantly remodelling in response to changing mechanical and environmental factors. This is particularly evident in the mineral component encrusting the collagenous framework. The mineral is principally in the form of calcium apatite, but calcium can exchange with strontium, both during the cellular processes of mineralisation and resorption and by passive exchange with the deposited crystals. Mineralisation is generally characterized by densitometry, but because of the differences in absorption cross sections of calcium and strontium it can be misleading in studies of composition. In this work we have used X-ray diffraction to identify calcium and strontium apatite and X-ray fluorescence to quantify strontium and calcium distribution. With the beam characteristics available from synchrotron radiation, this has enabled us to obtain microscopic resolution on thin sections of bone and cartilage from the equine metacarpophalangeal joint. Two issues have been investigated; the first is the distribution of mineral in the bone-cartilage interface and within individual trabeculae. In trabecular bone the ratio of strontium to calcium concentration was typically 0.0035 ± 0.0020, and higher by a factor of ∼3 at the periphery than in the centre of a trabeculum (possibly reflecting the more rapid turnover of mineral in the surface layer). In the dense subchondral bone the ratio was similar, approximately doubling in the calcified cartilage. The second objective was to explore the changes in mineralisation associated with development of osteoarthrosis. We analysed lesions showing cartilage thinning and changes in the trabecular organization and density of the underlying bone. At the centre of the lesion the ratio of strontium to calcium was much lower than that in normal tissue, although the calcified cartilage still showed a higher ratio than the underlying bone. In the superficially normal tissue around the lesion the calcified cartilage returned to a normal ratio much more rapidly than the underlying bone. These data demonstrate the complex relationship between changes in cartilage and the underlying bone.
Jayalakshmi, S; Platel, Kalpana
2016-02-01
Iron supplementation is usually given to pregnant and lactating women who may also have marginal deficiency of zinc. The negative impact of supplemental iron and calcium on zinc status is a cause of concern. The present investigation was undertaken to examine the effect of inclusion of iron and calcium in the diet at supplementary levels on zinc status of experimental rats. Groups of experimental rats were maintained on diets supplemented with iron (Molar ratio - Zn:Fe 1:30) and calcium (Molar ratio - Zn:Ca 1:667) both individually and in combination for six weeks. Zinc status of these rats was assessed by determining zinc concentration in circulation and in organs, and the activities of zinc containing enzymes in serum and liver. The zinc status of experimental rats receiving supplemental levels of iron and calcium was significantly compromised. Zinc concentration in serum, kidney, spleen and liver was reduced significantly by both these minerals. Six weeks of supplementation of iron and calcium individually, significantly reduced the activity of liver and serum superoxide dismutase and alkaline phosphatase. Activity of liver alcohol dehydrogenase was lowered in calcium supplemented group and in calcium + iron supplemented group, while that of carbonic anhydrase was significantly reduced by iron, calcium and their combination. Supplemental levels of iron and calcium, both individually and in combination, significantly compromised the zinc status of experimental rats. This negative effect of these two minerals was more prominent when these were supplemented for a period of six weeks.
Mathematical Model for the Mineralization of Bone
NASA Technical Reports Server (NTRS)
Martin, Bruce
1994-01-01
A mathematical model is presented for the transport and precipitation of mineral in refilling osteons. One goal of this model was to explain calcification 'halos,' in which the bone near the haversian canal is more highly mineralized than the more peripheral lamellae, which have been mineralizing longer. It was assumed that the precipitation rate of mineral is proportional to the difference between the local concentration of calcium ions and an equilibrium concentration and that the transport of ions is by either diffusion or some other concentration gradient-dependent process. Transport of ions was assumed to be slowed by the accumulation of mineral in the matrix along the transport path. ne model also mimics bone apposition, slowing of apposition during refilling, and mineralization lag time. It was found that simple diffusion cannot account for the transport of calcium ions into mineralizing bone, because the diffusion coefficient is two orders of magnitude too low. If a more rapid concentration gradient-driven means of transport exists, the model demonstrates that osteonal geometry and variable rate of refilling work together to produce calcification halos, as well as the primary and secondary calcification effect reported in the literature.
Rao, Ashit; Seto, Jong; Berg, John K; Kreft, Stefan G; Scheffner, Martin; Cölfen, Helmut
2013-08-01
The larval spicule matrix protein SM50 is the most abundant occluded matrix protein present in the mineralized larval sea urchin spicule. Recent evidence implicates SM50 in the stabilization of amorphous calcium carbonate (ACC). Here, we investigate the molecular interactions of SM50 and CaCO3 by investigating the function of three major domains of SM50 as small ubiquitin-like modifier (SUMO) fusion proteins - a C-type lectin domain (CTL), a glycine rich region (GRR) and a proline rich region (PRR). Under various mineralization conditions, we find that SUMO-CTL is monomeric and influences CaCO3 mineralization, SUMO-GRR aggregates into large protein superstructures and SUMO-PRR modifies the early CaCO3 mineralization stages as well as growth. The combination of these mineralization and self-assembly properties of the major domains synergistically enable the full-length SM50 to fulfill functions of constructing the organic spicule matrix as well as performing necessary mineralization activities such as Ca(2+) ion recruitment and organization to allow for proper growth and development of the mineralized larval sea urchin spicule. Copyright © 2013 Elsevier Inc. All rights reserved.
Increased Vertebral Bone Mineral in Response to Reduced Exercise in Amenorrheic Runners
Lindberg, Jill S.; Hunt, Marjorie M.; Wade, Charles E.; Powell, Malcolm R.; Ducey, Diane E.
1987-01-01
Seven female runners found to have exercise-induced amenorrhea and decreased bone mineral were reevaluated after 15 months. During the 15-month period, four runners took supplemental calcium and reduced their weekly running distance by 43%, resulting in an average 5% increase in body weight, increased estradiol levels and eumenorrhea. Bone mineral content increased from 1.003±0.097 to 1.070±0.089 grams per cm.2 Three runners continued to have amenorrhea, with no change in running distance or body weight. Estradiol levels remained abnormally low and there was no significant change in the bone mineral content, although all three took supplemental calcium. We found that early osteopenia associated with exercise-induced menstrual dysfunction improved when runners reduced their running distance, gained weight and became eumenorrheic. ImagesFigure 1. PMID:3825107
Overview of the amorphous precursor phase strategy in biomineralization
NASA Astrophysics Data System (ADS)
Weiner, Steve; Mahamid, Julia; Politi, Yael; Ma, Yurong; Addadi, Lia
2009-06-01
It was assumed for a long time that organisms produce minerals directly from a saturated solution. A few exceptions were known, including the well documented mineralized teeth of the chiton. In 1997 it was demon-strated that sea urchin larvae form their calcitic spicules by first depositing a highly unstable mineral phase called amorphous calcium carbonate. This strategy has since been shown to be used by animals from other phyla and for both aragonite and calcite. Recent evidence shows that vertebrate bone mineral may also be formed via a precursor phase of amorphous calcium carbonate. This strategy thus appears to be widespread. The challenge now is to understand the mechanisms by which these unstable phases are initially formed, how they are temporarily stabilized and how they are destabilized and transform into a crystalline mature product.
A multi-mineral natural product from red marine algae reduces colon polyp formation in C57BL/6 mice
Aslam, Muhammad N.; Bergin, Ingrid; Naik, Madhav; Paruchuri, Tejaswi; Hampton, Anna; Rehman, Muneeb; Dame, Michael K; Rush, Howard; Varani, James
2013-01-01
The goal of this study was to determine if a multi-mineral natural product derived from red marine algae, could reduce colon polyp formation in mice on a high fat diet. C57BL/6 mice were maintained for up to 18 months either on a high-fat “Western-style” diet or on a low-fat diet (AIN 76A), with or without the multi-mineral-supplement. To summarize, colon polyps were detected in 22 of 70 mice (31%) on the high-fat diet, but in only 2 of 70 mice (3%) receiving the mineral-supplemented high-fat diet (p<0.0001). Colon polyps were detected in 16 of 70 mice (23%) in the low-fat group; not significantly different from high-fat group but significantly higher than the high-fat-supplemented group (p=0.0006). This was in spite of the fact that the calcium level in the low-fat diet was comparable to the level of calcium in the high-fat diet containing the multi-mineral-product. Supplementation of the low-fat diet reduced the incidence to 8 of 70 mice (11% incidence). Taken together, these findings demonstrate that a multi-mineral natural product can protect mice on a high-fat diet against adenomatous polyp formation in the colon. These data suggest that increased calcium alone is insufficient to explain the lower incidence of colon polyps. PMID:23035966
Vitamins and bone health: beyond calcium and vitamin D.
Ahmadieh, Hala; Arabi, Asma
2011-10-01
Osteoporosis is a major health disorder associated with an increased risk of fracture. Nutrition is among the modifiable factors that influence the risk of osteoporosis and fracture. Calcium and vitamin D play important roles in improving bone mineral density and reducing the risk of fracture. Other vitamins appear to play a role in bone health as well. In this review, the findings of studies that related the intake and/or the status of vitamins other than vitamin D to bone health in animals and humans are summarized. Studies of vitamin A showed inconsistent results. Excessive, as well as insufficient, levels of retinol intake may be associated with compromised bone health. Deficiencies in vitamin B, along with the consequent elevated homocysteine level, are associated with bone loss, decreased bone strength, and increased risk of fracture. Deficiencies in vitamins C, E, and K are also associated with compromised bone health; this effect may be modified by smoking, estrogen use or hormonal therapy after menopause, calcium intake, and vitamin D. These findings highlight the importance of adequate nutrition in preserving bone mass and reducing the risk of osteoporosis and fractures. © 2011 International Life Sciences Institute.
Block copolymers for biomimetic composites
NASA Astrophysics Data System (ADS)
Calvert, Paul D.; Oner, Mualla; Burdon, Jeremy; Rieke, Peter C.; Farmer, Kelly
1993-07-01
Mineralized biological tissues can be regarded as composites where a fine reinforcement is laid down in a very controlled fashion within a tough polymeric matrix. Such materials include bone, antler, tooth enamel, mollusc shell, and crustacean shell. We have been exploring ways of forming similar structures by synthetic routes involving precipitation of reinforcing particles directly into a polymeric matrix. Part of this biomimetic approach requires polymer matrices which can exert a high degree of control over the mineralization process. Polymer gels have been formed from cross-linked methacrylates with various types of functionality within the gel. By incorporating calcium binding groups we have been producing gels which lead to preferential mineralization of the gel when it is incubated in a supersaturated solution of calcium oxalate or calcium carbonate. Similarly we have been incorporating silane groups within the gel in order to promote the deposition of silica in a gel body when it is immersed in a metastable solution of partly hydrolysed silicon alkoxides.
Regula, J; Cerba, A; Suliburska, J; Tinkov, A A
2018-03-01
The aim of this study was to measure the content of calcium, magnesium, iron, zinc, and copper and determine the bioavailability of these ingredients in gluten-free breads fortified with milk and selected seeds. Due to the increasing prevalence of celiac disease and mineral deficiencies, it has become necessary to produce food with higher nutritional values which maintains the appropriate product characteristics. This study was designed for gluten-free breads fortified with milk and seeds such as flax, poppy, sunflower seeds, pumpkin seeds or nuts, and flour with amaranth. Subsequently, digestion was performed in vitro and the potential bioavailability of the minerals was measured. In the case of calcium, magnesium, iron, and copper, higher bioavailability was observed in rice bread, and, in the case of copper and zinc, in buckwheat bread. This demonstrated a clear increase in bioavailability of all the minerals when the bread were enriched. However, satisfactory results are obtained only for the individual micronutrients.
Huang, Miaojun; Li, Tianjie; Pan, Ting; Zhao, Naru; Yao, Yongchang; Zhai, Zhichen; Zhou, Jiaan; Du, Chang; Wang, Yingjun
2016-10-01
Yeast cells have controllable biosorption on metallic ions during metabolism. However, few studies were dedicated to using yeast-regulated biomimetic mineralization process to control the strontium-doped positions in calcium phosphate microcapsules. In this study, the yeast cells were allowed to pre-adsorb strontium ions metabolically and then served as sacrificing template for the precipitation and calcination of mineral shell. The pre-adsorption enabled the microorganism to enrich of strontium ions into the inner part of the microcapsules, which ensured a slow-release profile of the trace element from the microcapsule. The co-culture with human marrow stromal cells showed that gene expressions of alkaline phosphatase and Collagen-I were promoted. The promotion of osteogenic differentiation was further confirmed in the 3D culture of cell-material complexes. The strategy using living microorganism as 'smart doping apparatus' to control incorporation of trace element into calcium phosphate paved a pathway to new functional materials for hard tissue regeneration.
Reyes Fernandez, Perla C.; Replogle, Rebecca A.; Wang, Libo; Zhang, Min; Fleet, James C.
2016-01-01
Low dietary calcium (Ca) intake during growth limits peak bone mass but physiological adaptation can prevent this adverse effect. To assess the genetic control on the physiologic response to dietary Ca restriction (RCR) we conducted a study in 51 BXD lines fed either 0.5% (basal) or 0.25% (low) Ca diets from 4–12 wks of age (n=8/line/diet). Ca absorption (CaAbs), femur bone mineral density (BMD), and bone mineral content (BMC) were examined. ANCOVA with body size as covariate was used to detect significant line and diet main effects, and line-by-diet interactions. Body size-corrected residuals were used for linkage mapping and to estimate heritability (h2). Loci controlling the phenotypes were identified using composite interval mapping on each diet and for the RCR. h2 of basal phenotypes (0.37– 0.43) and their RCR (0.32–0.38) was moderate. For each phenotype we identified multiple QTL on each diet and for the RCR. Several loci affected multiple traits: Chr 1 (88.3–90.6 cM, CaAbs, BMC), Chr 4 (45.8–49.2 cM, CaAbs, BMD, BMC), Chr 8 (28.6–31.6 cM, CaAbs, BMD RCR), and Chr 15 (13.6–24 cM, BMD, BMC), and (32.3–36 cM, CaAbs RCR, BMD). This suggests that gene clusters may regulate interdependent bone-related phenotypes. Using in silico expression QTL (eQTL) mapping and bioinformatic tools we identified novel candidates for the regulation of bone under Ca stress (Ext1, Deptor), and for the first time, we report genes modulating Ca absorption (Inadl, Sc4mol, Sh3rf1 and Dennd3), and both Ca and bone metabolism (Tceanc2, Tll1 and Aadat). Our data reveal gene-by-diet interactions and the existence of novel relationships between bone and Ca metabolism during growth. This article is protected by copyright. All rights reserved PMID:26636428
Berger, Sandrine Bittencourt; Cavalli, Vanessa; Martin, Airton Abrahão; Soares, Luis Eduardo Silva; Arruda, Marco Aurelio Zezzi; Brancalion, Marcel Luis; Giannini, Marcelo
2010-08-01
The objective of this study was to evaluate the effects of the combined use of light irradiation (LIR, halogen light, or LED/diode laser) and 35% hydrogen peroxide (35%HP) on human enamel mineral content. The use of high-intensity light has been indicated for acceleration of the rate of chemical bleaching; however, it is not known whether LIR can promote additional effects on enamel surfaces during the bleaching. One hundred enamel samples were obtained from third molars and randomly divided into 10 groups (n = 10). The control group (CG) remained untreated. Three whitening products were used: Whiteness HP Maxx, Pola Office, and Opalescence Xtra. Bleaching consisted of one session, and the products were applied three times to each specimen for 10 min each. The products were subjected, or not, to LIR during treatment with halogen light or LED/diode laser. The mineral concentration of enamel was determined before and after treatments using an FT-Raman spectroscope (FT-RS), and the amount of calcium lost from the bleached enamel surfaces was quantified with an atomic absorption spectrometer (AAS). FT-RS results showed a decreased mineral content after all treatments, with the exception of Pola Office when irradiated with LED/diode laser and the CG. The losses of calcium detected for Pola Office and Opalescence Xtra were similar for the three situations (without or with light irradiations), whereas for Whiteness HP Maxx the lowest calcium loss was detected without LIR. Most of the bleaching treatments investigated, in combination with LIR or not, can reduce the mineral content of enamel surface. LIR increased the calcium loss for Whiteness HP Maxx; no effects were observed for Pola Office and Opalescence Xtra.
Kazanci, M; Fratzl, P; Klaushofer, K; Paschalis, E P
2006-11-01
In addition to mechanical functions, bones have an essential role in metabolic activity as mineral reservoirs that are able to absorb and release ions. Bioapatite, considered the major component in the mineralized part of mammalian bones, is a calcium phosphate mineral with a structure that closely resembles hydroxyapatite (HA, Ca10[PO4]6[OH]2) with variable chemical substitutions. It is important to note that it continues to be chemically active long after it has been initially deposited. Detailed understanding of changes in the mineral phase as HA matures is essential for understanding how normal bone achieves its remarkable mechanical performance, how it is altered in disease, as well as the effects of therapeutic interventions. A model system for investigation of the in vivo maturation of HA is available, namely, the in vitro conversion of amorphous calcium phosphate (ACP) to HA in a supersaturated solution of calcium and phosphate ions. In the present study, this system was employed to correlate with the changes in chemistry and poorly crystalline HAP crystal size, shape, and habit. The results of the X-ray diffraction as well as Raman analyses showed that as the crystallites mature in the 002 and 310 directions both the full width at half-height and wavelength at maximum of the Raman peaks change as a function of reaction extent and crystallite maturation, size, and shape. Moreover, such analyses can be performed in intact bone specimens through Raman microspectroscopic and imaging analyses with a spatial resolution of 0.6-1 mu, by far superior to the one offered by other microspectroscopic techniques, thus potentially yielding important new information on the organization and mineral quality of normal and fragile bone.
Connolly, James; Kaufman, Megan; Rothman, Adam; Gupta, Rashmi; Redden, George; Schuster, Martin; Colwell, Frederick; Gerlach, Robin
2013-09-01
Two bacterial strains, Pseudomonas aeruginosa MJK1 and Escherichia coli MJK2, were constructed that both express green fluorescent protein (GFP) and carry out ureolysis. These two novel model organisms are useful for studying bacterial carbonate mineral precipitation processes and specifically ureolysis-driven microbially induced calcium carbonate precipitation (MICP). The strains were constructed by adding plasmid-borne urease genes (ureABC, ureD and ureFG) to the strains P. aeruginosa AH298 and E. coli AF504gfp, both of which already carried unstable GFP derivatives. The ureolytic activities of the two new strains were compared to the common, non-GFP expressing, model organism Sporosarcina pasteurii in planktonic culture under standard laboratory growth conditions. It was found that the engineered strains exhibited a lower ureolysis rate per cell but were able to grow faster and to a higher population density under the conditions of this study. Both engineered strains were successfully grown as biofilms in capillary flow cell reactors and ureolysis-induced calcium carbonate mineral precipitation was observed microscopically. The undisturbed spatiotemporal distribution of biomass and calcium carbonate minerals were successfully resolved in 3D using confocal laser scanning microscopy. Observations of this nature were not possible previously because no obligate urease producer that expresses GFP had been available. Future observations using these organisms will allow researchers to further improve engineered application of MICP as well as study natural mineralization processes in model systems. © 2013.
Zhou, Weibin; Moguche, Albanus O; Chiu, David; Murali-Krishna, Kaja; Baneyx, François
2014-04-01
Distributed and on-demand vaccine production could be game-changing for infectious disease treatment in the developing world by providing new therapeutic opportunities and breaking the refrigeration "cold chain". Here, we show that a fusion protein between a calcium phosphate binding domain and the model antigen ovalbumin can mineralize a biocompatible adjuvant in a single step. The resulting 50 nm calcium phosphate core-immunogen shell particles are comparable to soluble protein in inducing ovalbumin-specific antibody response and class switch recombination in mice. However, single dose vaccination with nanoparticles leads to higher expansion of ovalbumin-specific CD8(+) T cells upon challenge with an influenza virus bearing the ovalbumin-derived SIINFEKL peptide, and these cells produce high levels of IFN-γ. Furthermore, mice exhibit a robust antigen-specific CD8(+) T cell recall response when challenged with virus 8 months post-immunization. These results underscore the promise of immunogen-controlled adjuvant mineralization for just-in-time manufacturing of effective T cell vaccines. This paper reports that a fusion protein between a calcium phosphate binding domain and the model antigen ovalbumin can mineralize into a biocompatible adjuvant in a single step, enabling distributed and on-demand vaccine production and eliminating the need for refrigeration of vaccines. The findings highlight the possibility of immunogen-controlled adjuvant mineralization for just-in-time manufacturing of effective T cell vaccines. Copyright © 2014 Elsevier Inc. All rights reserved.
Bakker, Sjoerd F; Dik, Vincent K; Witte, Birgit I; Lips, Paul; Roos, Jan C; Van Bodegraven, Adriaan A
2013-06-01
Decreased bone mineral density (BMD) is common in Crohn's disease (CD) patients. This paper reports on the prevalence of decreased BMD in a referral cohort study of CD-patients next to the change of BMD over time in relation with CD-associated clinical characteristics. 205 CD patients of a referral hospital were enrolled between January1998-January 2010 when measurement of BMD by dual X-ray absorptiometry (DXA) was available. Follow-up DXA scan was performed in subjects with known risk factors besides Crohn indicative for low BMD. Treatment of CD patients was according to a protocol which is comparable to the current (inter)national guidelines. In osteopenic patients, supplemental vitamin D (800 IU) and Calcium (500-1000 mg) were prescribed. Mean BMD at baseline was 0.97 ± 0.16 gram/cm(2) in lumbar spine and 0.87 ± 0.12 gram/cm(2) in the total hip. At baseline, higher age and low Body Mass Index (BMI), were negatively correlated with BMD. Eighty-four patients underwent a second BMD assessment with a median interval period of 4 years (IQR 3-6). A mean annual increase of +0.76% (95%CI: -2.63%; +3.87%) in lumbar spine and +0.43% (95%CI: -2.65% ; +1.11%) in total hip was observed. Higher age, male sex, low BMI, and a higher age at diagnosis of CD were associated with low BMD. Follow-up of BMD in CD patients showed a contraintuitive small increase of BMD at lumbar spine and total hip in CD patients only using supplemental vitamin D and calcium next to strict treatment of CD. Copyright © 2012 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.
Calcium revisited, part III: effect of dietary calcium on BMD and fracture risk
Burckhardt, Peter
2015-01-01
Food can be an excellent source of calcium. Dietary calcium is in general as well absorbed as calcium supplements, and exerts the same effects on bone. The main sources are dairy products, but also some vegetables and fruits contain considerable amounts of calcium. Mineral water can serve as a supplement. Cross-sectional, longitudinal and some interventional trials have shown positive effects on bone metabolism, bone density and bone loss. But the effect on fracture incidence is less certain, and that of milk, the most studied dairy product, still unproven. PMID:26331006
Calcium biofortification of crops
USDA-ARS?s Scientific Manuscript database
More than half of the world's population is deficient in calcium (Ca), iron (Fe), iodine (I), magnesium (Mg), selenium (Se), or zinc (Zn). The consumption of plants, directly or via livestock, containing inadequate concentrations of particular minerals causes these deficiencies. Agronomic and geneti...
Influence of zinc on the calcium carbonate biomineralization of Halomonas halophila
2012-01-01
Background The salt tolerance of halophilic bacteria make them promising candidates for technical applications, like isolation of salt tolerant enzymes or remediation of contaminated saline soils and waters. Furthermore, some halophilic bacteria synthesize inorganic solids resulting in organic–inorganic hybrids. This process is known as biomineralization, which is induced and/or controlled by the organism. The adaption of the soft and eco-friendly reaction conditions of this formation process to technical syntheses of inorganic nano materials is desirable. In addition, environmental contaminations can be entrapped in biomineralization products which facilitate the subsequent removal from waste waters. The moderately halophilic bacteria Halomonas halophila mineralize calcium carbonate in the calcite polymorph. The biomineralization process was investigated in the presence of zinc ions as a toxic model contaminant. In particular, the time course of the mineralization process and the influence of zinc on the mineralized inorganic materials have been focused in this study. Results H. halophila can adapt to zinc contaminated medium, maintaining the ability for biomineralization of calcium carbonate. Adapted cultures show only a low influence of zinc on the growth rate. In the time course of cultivation, zinc ions accumulated on the bacterial surface while the medium depleted in the zinc contamination. Intracellular zinc concentrations were below the detection limit, suggesting that zinc was mainly bound extracellular. Zinc ions influence the biomineralization process. In the presence of zinc, the polymorphs monohydrocalcite and vaterite were mineralized, instead of calcite which is synthesized in zinc-free medium. Conclusions We have demonstrated that the bacterial mineralization process can be influenced by zinc ions resulting in the modification of the synthesized calcium carbonate polymorph. In addition, the shape of the mineralized inorganic material is chancing through the presence of zinc ions. Furthermore, the moderately halophilic bacterium H. halophila can be applied for the decontamination of zinc from aqueous solutions. PMID:23198844
Rice, Karen; Price, Jason R.; Szymanski, David W.
2013-01-01
Mineral weathering rates and a forest macronutrient uptake stoichiometry were determined for the forested, metabasaltic Hauver Branch watershed in north-central Maryland, USA. Previous studies of Hauver Branch have had an insufficient number of analytes to permit determination of rates of all the minerals involved in chemical weathering, including biomass. More equations in the mass-balance matrix were added using existing mineralogic information. The stoichiometry of a deciduous biomass term was determined using multi-year weekly to biweekly stream-water chemistry for a nearby watershed, which drains relatively unreactive quartzite bedrock.At Hauver Branch, calcite hosts ~38 mol% of the calcium ion (Ca2+) contained in weathering minerals, but its weathering provides ~90% of the stream water Ca2+. This occurs in a landscape with a regolith residence time of more than several Ka (kiloannum). Previous studies indicate that such old regolith does not typically contain dissolving calcite that affects stream Ca2+/Na+ ratios. The relatively high calcite dissolution rate likely reflects dissolution of calcite in fractures of the deep critical zone.Of the carbon dioxide (CO2) consumed by mineral weathering, calcite is responsible for approximately 27%, with the silicate weathering consumption rate far exceeding that of the global average. The chemical weathering of mafic terrains in decaying orogens thus may be capable of influencing global geochemical cycles, and therefore, climate, on geological timescales. Based on carbon-balance calculations, atmospheric-derived sulfuric acid is responsible for approximately 22% of the mineral weathering occurring in the watershed. Our results suggest that rising air temperatures, driven by global warming and resulting in higher precipitation, will cause the rate of chemical weathering in the Hauver Branch watershed to increase until a threshold temperature is reached. Beyond the threshold temperature, increased recharge would produce a shallower groundwater table and reduced chemical weathering rates.
USDA-ARS?s Scientific Manuscript database
Calcium absorption and whole-body bone mineral content are greater in young adolescents who receive 8 g/d of Synergy, a mixture of inulin-type fructans (ITF), compared with those who received a maltodextrin control. Not all adolescents responded to this intervention, however. We evaluated 32 respond...
Identification of mineral compositions in some renal calculi by FT Raman and IR spectral analysis
NASA Astrophysics Data System (ADS)
Tonannavar, J.; Deshpande, Gouri; Yenagi, Jayashree; Patil, Siddanagouda B.; Patil, Nikhil A.; Mulimani, B. G.
2016-02-01
We present in this paper accurate and reliable Raman and IR spectral identification of mineral constituents in nine samples of renal calculi (kidney stones) removed from patients suffering from nephrolithiasis. The identified mineral components include Calcium Oxalate Monohydrate (COM, whewellite), Calcium Oxalate Dihydrate (COD, weddellite), Magnesium Ammonium Phosphate Hexahydrate (MAPH, struvite), Calcium Hydrogen Phosphate Dihydrate (CHPD, brushite), Pentacalcium Hydroxy Triphosphate (PCHT, hydroxyapatite) and Uric Acid (UA). The identification is based on a satisfactory assignment of all the observed IR and Raman bands (3500-400 cm- 1) to chemical functional groups of mineral components in the samples, aided by spectral analysis of pure materials of COM, MAPH, CHPD and UA. It is found that the eight samples are composed of COM as the common component, the other mineral species as common components are: MAPH in five samples, PCHT in three samples, COD in three samples, UA in three samples and CHPD in two samples. One sample is wholly composed of UA as a single component; this inference is supported by the good agreement between ab initio density functional theoretical spectra and experimental spectral measurements of both sample and pure material. A combined application of Raman and IR techniques has shown that, where the IR is ambiguous, the Raman analysis can differentiate COD from COM and PCHT from MAPH.
Identification of mineral compositions in some renal calculi by FT Raman and IR spectral analysis.
Tonannavar, J; Deshpande, Gouri; Yenagi, Jayashree; Patil, Siddanagouda B; Patil, Nikhil A; Mulimani, B G
2016-02-05
We present in this paper accurate and reliable Raman and IR spectral identification of mineral constituents in nine samples of renal calculi (kidney stones) removed from patients suffering from nephrolithiasis. The identified mineral components include Calcium Oxalate Monohydrate (COM, whewellite), Calcium Oxalate Dihydrate (COD, weddellite), Magnesium Ammonium Phosphate Hexahydrate (MAPH, struvite), Calcium Hydrogen Phosphate Dihydrate (CHPD, brushite), Pentacalcium Hydroxy Triphosphate (PCHT, hydroxyapatite) and Uric Acid (UA). The identification is based on a satisfactory assignment of all the observed IR and Raman bands (3500-400c m(-1)) to chemical functional groups of mineral components in the samples, aided by spectral analysis of pure materials of COM, MAPH, CHPD and UA. It is found that the eight samples are composed of COM as the common component, the other mineral species as common components are: MAPH in five samples, PCHT in three samples, COD in three samples, UA in three samples and CHPD in two samples. One sample is wholly composed of UA as a single component; this inference is supported by the good agreement between ab initio density functional theoretical spectra and experimental spectral measurements of both sample and pure material. A combined application of Raman and IR techniques has shown that, where the IR is ambiguous, the Raman analysis can differentiate COD from COM and PCHT from MAPH. Copyright © 2015 Elsevier B.V. All rights reserved.
Bahtiri, Elton; Islami, Hilmi; Hoxha, Rexhep; Bytyqi, Hasime Qorraj-; Sermaxhaj, Faton; Halimi, Enis
2014-01-01
Background and objective: There is paucity of evidence in southeastern Europe and Kosovo regarding dairy products consumption and association with bone mineral density (BMD). Therefore, the objective of present study was to assess calcium intake and dairy products consumption and to investigate relationship with total hip BMD in a Kosovo women sample. Methods: This cross-sectional study included a sample of 185 women divided into respective groups according to total hip BMD. All the study participants completed a food frequency questionnaire and underwent dual-energy X-ray absorptiometry (DEXA) to estimate BMD. Nonparametric tests were performed to compare characteristics of the groups. Results: The average dietary calcium intake was 818.41 mg/day. Only 16.75% of the subjects met calcium recommended dietary reference intakes (DRIs). There were no significant differences between low BMD group and normal BMD group regarding average dietary calcium intake, but it was significantly higher in BMDT3 subgroup than in BMDT2 and BMDT1 subgroups. Conclusions: The results of this study demonstrate significant relationship of daily dietary calcium intake with upper BMD tertile. Further initiatives are warranted from this study to highlight the importance of nutrition education. PMID:25568548
Biomineralization processes of calcite induced by bacteria isolated from marine sediments
Wei, Shiping; Cui, Hongpeng; Jiang, Zhenglong; Liu, Hao; He, Hao; Fang, Nianqiao
2015-01-01
Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10−4 mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments. PMID:26273260
Wittich, A; Mautalen, C A; Oliveri, M B; Bagur, A; Somoza, F; Rotemberg, E
1998-08-01
The total skeletal bone mineral content (BMC), bone mineral density (BMD), bone size, and body composition were measured by dual-energy x-ray absorptiometry (DXA) in all professional male football players of a 1st division team (n = 24) and age- and BMI-matched (n = 22) controls (less than 3 hours of recreational sport activities per week). Average (+/- 1 SD) age of the athletes was 22.6 +/- 2.5 years. Intensive training is conducted during 48 weeks a year for 20-22 hours/week. The length of the registered playing career before the study was 8.2 +/- 2.7 years. Total skeleton BMC was 18.0% (P < 0.001) greater in the football players. The difference resulted from the sum of 5.2% (P < 0.02) increment of bone size and 12.3% (P < 0.001) increment of BMD. The analysis of skeletal subareas revealed that the difference of the BMC and BMD was greater at the level of the pelvis and legs compared with the arms or trunk. The BMC and BMD of the head was equal for both groups. Also, the bone size of the legs and pelvis was significantly greater for the players compared with controls; there was no difference at the level of the arms or head. Within the group of football players the increment of total skeleton BMD was similar in the young players, with less than 7 years of practice (age 20.6 +/- 0.9 years) compared with relative older players (age 24.6 +/- 1.9) with more than 7 years of practice. Lean body mass was significantly greater in the players (63.3 +/- 4.0 kg) compared with the controls (56.7 +/- 3.6, P < 0.001) whereas fat mass was markedly lower (9.4 +/- 2.9 kg versus 14.9 +/- 6.3 kg), P < 0.002). The BMD of the controls was significantly correlated to total weight, height, and lean mass whereas the BMD of the players was only correlated to muscle mass. The calcium intake from dairy products was similar in both groups. The range of calcium intake was wide among the players (184-2519 mg/day) but it was not significantly correlated to BMD (r = 0.03). In conclusion, male professional football players develop a significant increment of BMC as a result of increased bone size and density. This is already present at the end of the second decade and maintained at least to the end of the third decade in active players. As in other high impact loading sports, the effect on area is specific involving mainly the pelvis and legs. The increment was totally unrelated to the calcium intake from dairy products. The fate of the increased BMC after intensive training is discontinued should be assessed. However, if the findings of the present cross-sectional study are supported by detailed longitudinal investigations, the presently reported observations might be important for the prevention of future osteoporotic fractures.
Jamalian, Azadeh; Sneekes, Evert-Jan; Wienk, Hans; Dekker, Lennard J. M.; Ruttink, Paul J. A.; Ursem, Mario; Luider, Theo M.; Burgers, Peter C.
2014-01-01
Here we describe a new method to identify calcium-binding sites in proteins using high-resolution liquid chromatography-mass spectrometry in concert with calcium-directed collision-induced dissociations. Our method does not require any modifications to the liquid chromatography-mass spectrometry apparatus, uses standard digestion protocols, and can be applied to existing high-resolution MS data files. In contrast to NMR, our method is applicable to very small amounts of complex protein mixtures (femtomole level). Calcium-bound peptides can be identified using three criteria: (1) the calculated exact mass of the calcium containing peptide; (2) specific dissociations of the calcium-containing peptide from threonine and serine residues; and (3) the very similar retention times of the calcium-containing peptide and the free peptide. PMID:25023127
Kılıç Altun, Serap; Dinç, Hikmet; Paksoy, Nilgün; Temamoğulları, Füsun Karaçal; Savrunlu, Mehmet
2017-01-01
The substantial of mineral ingredients in honey may symbolize the existence of elements in the plants and soil of the vicinity wherein the honey was taken. The aim of this study was to detect the levels of 13 elements (Potassium (K), Sodium (Na), Calcium (Ca), Iron (Fe), Zinc (Zn), Cadmium (Cd), Copper (Cu), Manganese (Mn), Lead (Pb), Nickel (Ni), Chromium (Cr), Aluminum (Al), and Selenium (Se)) in unifloral and multifloral honey samples from south and east regions of Turkey. Survey of 71 honey samples from seven different herbal origins, picked up from the south and east region of Turkey, was carried out to determine their mineral contents during 2015-2016. The mineral contents were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The most abundant minerals were K, Na, and Ca ranging within 1.18-268 ppm, 0.57-13.1 ppm, and 0.77-4.5 ppm, respectively. Zn and Cu were the most abundant trace element while Pb, Cd, Ni, and Cr were the lowest heavy metals in the honey samples surveyed, with regard to the concentrations of heavy metals such as Zn, Cu, Pb, Cd, Ni, and Cr suggested and influence of the botanical origin of element composition. Geochemical and geographical differences are probably related to the variations of the chemical components of honey samples.
Munshi, Rafiya; Kochhar, Anita; Garg, Vishal
2015-01-01
Osteoporosis is a disorder of bones with increasing risk among women. However, a number of modifiable factors can help in combating this disorder. Present study examined the relationship of diet and physical activity and risk of osteoporosis through biochemical tests, bone mass density (BMD) scores, and standard questionnaires. Genetic risk for osteoporosis, presence of osteoarthritis, and thyroid problems were found among 8%, 7%, and 3% of participants, respectively; and 78% had onset of menopause between 47 to 55 years of age. Results revealed that less intake of proteins, minerals, and diverse fruit and vegetable consumption was significantly (p≤0.05; 0.01) correlated with decreased BMD score and serum calcium. It was concluded that adequate intake of varied fruits and vegetables, good protein, habit of daily physical activity, adequate sun exposure, and dietary calcium, may play a promising role in decreasing the risk of osteoporosis among women of this age group.
NASA Astrophysics Data System (ADS)
Nehrke, Gernot; Poigner, Harald; Wilhelms-Dick, Dorothee; Brey, Thomas; Abele, Doris
2012-05-01
We analyzed shell cuts of five individuals of the Antarctic bivalve Laternula elliptica from three locations along the Antarctic Peninsula by means of Confocal Raman Microscopy (CRM) as well as Electron Microprobe (EMP). The shell of L. elliptica has been previously described as being composed of aragonite exclusively. Now, CRM mapping reveals that three polymorphs of calcium carbonate - aragonite, calcite, and vaterite - are present in the chondrophore region of the examined individuals. Annual shell growth layers continue through aragonite and vaterite, suggesting simultaneous mineralization of both polymorphs. Spatially congruent EMP scans showed that the calcium carbonate polymorph affects the distribution of magnesium and strontium within the chondrophore. This is, to our knowledge, the first report of the coexistence of these three calcium carbonate polymorphs within the mineralized structures of a marine calcifying organism. Particularly the presence of vaterite is unexpected, but shows striking similarities to some fish otoliths. The strong effect of the calcium carbonate polymorph on trace element incorporation restrict the suitability of magnesium and strontium based proxies for the chondrophore area of L. elliptica.
Osteoblast response to zirconia-hybridized pyrophosphate-stabilized amorphous calcium phosphate
Whited, Bryce M.; Skrtic, Drago; Love, Brian J.
2006-01-01
Calcium phosphate bioceramics, such as hydroxyapatite, have long been used as bone substitutes because of their proven biocompatibility and bone binding properties in vivo. Recently, a zirconia-hybridized pyrophosphate-stabilized amorphous calcium phosphate (Zr-ACP) has been synthesized, which is more soluble than hydroxyapatite and allows for controlled release of calcium and phosphate ions. These ions have been postulated to increase osteoblast differentiation and mineralization in vitro. The focus of this work is to elucidate the physicochemical properties of Zr-ACP and to measure cell response to Zr-ACP in vitro using a MC3T3-E1 mouse calvarial-derived osteoprogenitor cell line. Cells were cultured in osteogenic medium and mineral was added to culture at different stages in cell maturation. Culture in the presence of Zr-ACP showed significant increases in cell proliferation, alkaline phosphatase activity (ALP), and osteopontin (OPN) synthesis, whereas collagen synthesis was unaffected. In addition, calcium and phosphate ion concentrations and medium pH were found to transiently increase with the addition of Zr-ACP, and are hypothesized to be responsible for the osteogenic effect of Zr-ACP. PMID:16278876
Mao, Yelin; Satchell, Paul G.; Luan, Xianghong; Diekwisch, Thomas G.H.
2015-01-01
The two major proteins involved in vertebrate enamel formation and echinoderm sea urchin tooth biomineralization, amelogenin and SM50, are both characterized by elongated polyproline repeat domains in the center of the macromolecule. To determine the role of polyproline repeat polypeptides in basal deuterostome biomineralization, we have mapped the localization of SM50 as it relates to crystal growth, conducted self-assembly studies of SM50 repeat polypeptides, and examined their effect on calcium carbonate and apatite crystal growth. Electron micrographs of the growth zone of Strongylocentrotus purpuratus sea urchin teeth documented a series of successive events from intravesicular mineral nucleation to mineral deposition at the interface between tooth surface and odontoblast syncytium. Using immunohistochemistry, SM50 was detected within the cytoplasm of cells associated with the developing tooth mineral, at the mineral secreting front, and adjacent to initial mineral deposits, but not in muscles and ligaments. Polypeptides derived from the SM50 polyproline alternating hexa- and hepta-peptide repeat region (SM50P6P7) formed highly discrete, donut-shaped self-assembly patterns. In calcium carbonate crystal growth studies, SM50P6P7 repeat peptides triggered the growth of expansive networks of fused calcium carbonate crystals while in apatite growth studies, SM50P6P7 peptides facilitated the growth of needle-shaped and parallel arranged crystals resembling those found in developing vertebrate enamel. In comparison, SM50P6P7 surpassed the PXX24 polypeptide repeat region derived from the vertebrate enamel protein amelogenin in its ability to promote crystal nucleation and appositional crystal growth. Together, these studies establish the SM50P6P7 polyproline repeat region as a potent regulator in the protein-guided appositional crystal growth that occurs during continuous tooth mineralization and eruption. In addition, our studies highlight the role of species-specific polyproline repeat motifs in the formation of discrete self-assembled matrices and the resulting control of mineral growth. PMID:26194158
Mao, Yelin; Satchell, Paul G; Luan, Xianghong; Diekwisch, Thomas G H
2016-01-01
The two major proteins involved in vertebrate enamel formation and echinoderm sea urchin tooth biomineralization, amelogenin and SM50, are both characterized by elongated polyproline repeat domains in the center of the macromolecule. To determine the role of polyproline repeat polypeptides in basal deuterostome biomineralization, we have mapped the localization of SM50 as it relates to crystal growth, conducted self-assembly studies of SM50 repeat polypeptides, and examined their effect on calcium carbonate and apatite crystal growth. Electron micrographs of the growth zone of Strongylocentrotus purpuratus sea urchin teeth documented a series of successive events from intravesicular mineral nucleation to mineral deposition at the interface between tooth surface and odontoblast syncytium. Using immunohistochemistry, SM50 was detected within the cytoplasm of cells associated with the developing tooth mineral, at the mineral secreting front, and adjacent to initial mineral deposits, but not in muscles and ligaments. Polypeptides derived from the SM50 polyproline alternating hexa- and hepta-peptide repeat region (SM50P6P7) formed highly discrete, donut-shaped self-assembly patterns. In calcium carbonate crystal growth studies, SM50P6P7 repeat peptides triggered the growth of expansive networks of fused calcium carbonate crystals while in apatite growth studies, SM50P6P7 peptides facilitated the growth of needle-shaped and parallel arranged crystals resembling those found in developing vertebrate enamel. In comparison, SM50P6P7 surpassed the PXX24 polypeptide repeat region derived from the vertebrate enamel protein amelogenin in its ability to promote crystal nucleation and appositional crystal growth. Together, these studies establish the SM50P6P7 polyproline repeat region as a potent regulator in the protein-guided appositional crystal growth that occurs during continuous tooth mineralization and eruption. In addition, our studies highlight the role of species-specific polyproline repeat motifs in the formation of discrete self-assembled matrices and the resulting control of mineral growth. Copyright © 2015 Elsevier GmbH. All rights reserved.
Hindlimb unloading of growing rats: a model for predicting skeletal changes during space flight.
Morey-Holton, E R; Globus, R K
1998-05-01
A model that uses hindlimb unloading of rats was developed to study the consequences of skeletal unloading and reloading as occurs during and following space flight. Studies using the model were initiated two decades ago and further developed at National Aeronautics and Space Administration (NASA)-Ames Research Center. The model mimics some aspects of exposure to microgravity by removing weightbearing loads from the hindquarters and producing a cephalic fluid shift. Unlike space flight, the forelimbs remain loaded in the model, providing a useful internal control to distinguish between the local and systemic effects of hindlimb unloading. Rats that are hindlimb unloaded by tail traction gain weight at the same rate as pairfed controls, and glucocorticoid levels are not different from controls, suggesting that systemic stress is minimal. Unloaded bones display reductions in cancellous osteoblast number, cancellous mineral apposition rate, trabecular bone volume, cortical periosteal mineralization rate, total bone mass, calcium content, and maturation of bone mineral relative to controls. Subsequent studies reveal that these changes also occur in rats exposed to space flight. In hindlimb unloaded rats, bone formation rates and masses of unloaded bones decline relative to controls, while loaded bones do not change despite a transient reduction in serum 1,25-dihydroxyvitamin D (1,25D) concentrations. Studies using the model to evaluate potential countermeasures show that 1,25D, growth hormone, dietary calcium, alendronate, and muscle stimulation modify, but do not completely correct, the suppression of bone growth caused by unloading, whereas continuous infusion of transforming growth factor-beta2 or insulin-like growth factor-1 appears to protect against some of the bone changes caused by unloading. These results emphasize the importance of local as opposed to systemic factors in the skeletal response to unloading, and reveal the pivotal role that osteoblasts play in the response to gravitational loading. The hindlimb unloading model provides a unique opportunity to evaluate in detail the physiological and cellular mechanisms of the skeletal response to weightbearing loads, and has proven to be an effective model for space flight.
Hindlimb unloading of growing rats: a model for predicting skeletal changes during space flight
NASA Technical Reports Server (NTRS)
Morey-Holton, E. R.; Globus, R. K.
1998-01-01
A model that uses hindlimb unloading of rats was developed to study the consequences of skeletal unloading and reloading as occurs during and following space flight. Studies using the model were initiated two decades ago and further developed at National Aeronautics and Space Administration (NASA)-Ames Research Center. The model mimics some aspects of exposure to microgravity by removing weightbearing loads from the hindquarters and producing a cephalic fluid shift. Unlike space flight, the forelimbs remain loaded in the model, providing a useful internal control to distinguish between the local and systemic effects of hindlimb unloading. Rats that are hindlimb unloaded by tail traction gain weight at the same rate as pairfed controls, and glucocorticoid levels are not different from controls, suggesting that systemic stress is minimal. Unloaded bones display reductions in cancellous osteoblast number, cancellous mineral apposition rate, trabecular bone volume, cortical periosteal mineralization rate, total bone mass, calcium content, and maturation of bone mineral relative to controls. Subsequent studies reveal that these changes also occur in rats exposed to space flight. In hindlimb unloaded rats, bone formation rates and masses of unloaded bones decline relative to controls, while loaded bones do not change despite a transient reduction in serum 1,25-dihydroxyvitamin D (1,25D) concentrations. Studies using the model to evaluate potential countermeasures show that 1,25D, growth hormone, dietary calcium, alendronate, and muscle stimulation modify, but do not completely correct, the suppression of bone growth caused by unloading, whereas continuous infusion of transforming growth factor-beta2 or insulin-like growth factor-1 appears to protect against some of the bone changes caused by unloading. These results emphasize the importance of local as opposed to systemic factors in the skeletal response to unloading, and reveal the pivotal role that osteoblasts play in the response to gravitational loading. The hindlimb unloading model provides a unique opportunity to evaluate in detail the physiological and cellular mechanisms of the skeletal response to weightbearing loads, and has proven to be an effective model for space flight.
NASA Technical Reports Server (NTRS)
Ciftcioglu, Neva; Mckay, David S.; Mathew, Grace; Kajander, E. Olavi
2006-01-01
There is some debate in microbiology as to whether Nanobacteria (NB) are alive. This paper reviews some aspects of NB. In summary, Nanobacteria is a perfect model for studying biogenic mineralization/calcification because NB a) are self-replicating particles and have less complicated metabolic pathways b) accumulate calcium and phosphate under physiological conditions, c)produce a calcium phosphate mineral similar to bone, d) exist in physical conditions (pH, gravity, temperature, etc) that are easy to manipulate, and which can be replicated for the physiological model.
Khripach, L V; Mikhaylova, R I; Koganova, Z I; Knyazeva, T D; Alekseeva, A V; Savostikova, O N; Ryzhova, I N; Kruglova, E V; Revzova, T L
2015-01-01
There are discussed the changes of an array of indices of the oxidative status in chronic administration of colloidal calcium carbonate preparation with faucet and low-mineralized drinking water to rats. Slight differences between significant effects of administration of 3 and 30 mg/L of preparation permit to suggest that the process of its incoming delivery into organism of rats has a bottleneck in the nature of total capacity of macrophages of intestinal lymphoid tissue to absorption of particles.
The rheological effect of water on lower mantle minerals
NASA Astrophysics Data System (ADS)
Muir, J.; Brodholt, J. P.
2017-12-01
The presence of water in many upper mantle minerals has been shown to have a large effect on their rheology in what is generally known as "hydrolytic weakening". A growing number of studies are finding that incorporating a water dependent rheology into global mantle convection models has a strong effect on global dynamics. However, while there is an abundance of experimental evidence showing that upper mantle minerals deformed under hydrous conditions are significantly weaker than when dry, there is no such experimental evidence for lower mantle minerals. In this study we use DFT methods to calculate the partitioning of water between different sites in lower mantle minerals (bridgmanite, cubic and tetragonal calcium perovskite, ferropericlase and phase H) which allows us to speculate on the effects of water on the rheology and phase stability of lower mantle minerals under various conditions. The effect of water on lower mantle minerals is found to depend strongly upon both water content and temperature. Under typical lower mantle conditions and with reasonable water concentrations (<1000 ppm), water partitions preferentially into bridgmanite but with a mechanism that does not increase the concentration of Mg or Si vacancies in bridgmanite and thus is unlikely to affect its rheology. In cooler conditions, such as in a descending slab, water partitions into calcium perovskite or forms water rich aluminous phases. The presence of water in calcium perovskite has large effects on the preferred phase and can induce multiple phase transitions at varying depths of the mantle depending upon both water content and slab temperature. These transitions are likely to be seismically anomalous and could cause large and characteristic seismic heterogeneity in descending slabs.
El-Hajj Fuleihan, Ghada; Nabulsi, Mona; Tamim, Hala; Maalouf, Joyce; Salamoun, Mariana; Khalife, Hassan; Choucair, Mahmoud; Arabi, Asma; Vieth, Reinhold
2006-02-01
Despite the high prevalence of hypovitaminosis D in children and adolescents worldwide, the impact of vitamin D deficiency on skeletal health is unclear. One hundred seventy-nine girls, ages 10-17 yr, were randomly assigned to receive weekly oral vitamin D doses of 1,400 IU (equivalent to 200 IU/d) or 14,000 IU (equivalent to 2,000 IU/d) in a double-blind, placebo-controlled, 1-yr protocol. Areal bone mineral density (BMD) and bone mineral content (BMC) at the lumbar spine, hip, forearm, total body, and body composition were measured at baseline and 1 yr. Serum calcium, phosphorus, alkaline phosphatase, and vitamin D metabolites were measured during the study. In the overall group of girls, lean mass increased significantly in both treatment groups (P < or = 0.05); bone area and total hip BMC increased in the high-dose group (P < 0.02). In premenarcheal girls, lean mass increased significantly in both treatment groups, and there were consistent trends for increments in BMD and/or BMC at several skeletal sites, reaching significance at lumbar spine BMD in the low-dose group and at the trochanter BMC in both treatment groups. There was no significant change in lean mass, BMD, or BMC in postmenarcheal girls. Vitamin D replacement had a positive impact on musculoskeletal parameters in girls, especially during the premenarcheal period.
Tagliati, Sylvie; Saccomandi, Daniela; Brusaferro, Andrea; Busoli, Laura; Scala, Andrea; Malaventura, Cristina; Borgna-Pignatti, Caterina
2018-01-01
Adult-type hypolactasia (ATH) is a clinical syndrome of primary lactase deficiency. A lactose-free diet is advisable to avoid the symptoms linked to the condition, but this potentially creates problems for optimal bone mineralization due to reduced calcium intake. To evaluate the effect of the lactose-free diet on the bone mineral status (BMS), we compared the phalangeal BMS of adolescents with ATH to that of peers on a normal diet. Also, we analyzed the correlations between BMS and dietary behavior, physical exercise, and calcium and vitamin D intake. A total of 102 cases and 102 healthy controls filled out a diet record and underwent phalangeal Quantitative Ultrasound (QUS). No difference in BMS was observed. The time spent on lactose-free diet (4.8 ± 3.1 years) was inversely correlated to the BMS. More than 98% of cases consumed lactose-free milk, but calcium and vitamin D intake were significantly lower. Calcium intake was correlated to physical exercise but not to BMS. Our results suggest that a lactose-free diet does not affect the phalangeal BMS of adolescents with primary lactase deficiency when their diet includes lactose-free cow’s milk. However, there is still a significantly lower calcium intake than in the population reference. The inverse correlation observed between the BMS and the time spent on a lactose-free diet suggests that a long-term follow-up is advisable. PMID:29723971
Georgakopoulos, Evangelos; Santos, Rafael M; Chiang, Yi Wai; Manovic, Vasilije
2017-02-21
The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with sufficient heavy metal adsorption capacity. To this end, blast furnace slag, a residue from iron-making, is utilized as the starting material. Calcium is selectively extracted from the slag by leaching with acetic acid (2 M CH3COOH) as the extraction agent. The filtered leachate is subsequently physico-chemically purified and then carbonated to form precipitated calcium carbonate (PCC) of high purity (<2 wt% non-calcium impurities, according to ICP-MS analysis). Sodium hydroxide is added to neutralize the regenerated acetate. The morphological properties of the resulting calcitic PCC are tuned for its potential application as a filler in papermaking. In parallel, the residual solids from the extraction stage are subjected to hydrothermal conversion in a caustic solution (2 M NaOH) that leads to the predominant formation of a particular zeolitic mineral phase (detected by XRD), namely analcime (NaAlSi2O6∙H2O). Based on its ability to adsorb Ni 2+ , as reported from batch adsorption experiments and ICP-OES analysis, this product can potentially be used in wastewater treatment or for environmental remediation applications.
Georgakopoulos, Evangelos; Santos, Rafael M.; Chiang, Yi Wai; Manovic, Vasilije
2017-01-01
The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with sufficient heavy metal adsorption capacity. To this end, blast furnace slag, a residue from iron-making, is utilized as the starting material. Calcium is selectively extracted from the slag by leaching with acetic acid (2 M CH3COOH) as the extraction agent. The filtered leachate is subsequently physico-chemically purified and then carbonated to form precipitated calcium carbonate (PCC) of high purity (<2 wt% non-calcium impurities, according to ICP-MS analysis). Sodium hydroxide is added to neutralize the regenerated acetate. The morphological properties of the resulting calcitic PCC are tuned for its potential application as a filler in papermaking. In parallel, the residual solids from the extraction stage are subjected to hydrothermal conversion in a caustic solution (2 M NaOH) that leads to the predominant formation of a particular zeolitic mineral phase (detected by XRD), namely analcime (NaAlSi2O6∙H2O). Based on its ability to adsorb Ni2+, as reported from batch adsorption experiments and ICP-OES analysis, this product can potentially be used in wastewater treatment or for environmental remediation applications. PMID:28287605
Statolith formation in Cnidaria: effects of cadmium on Aurelia statoliths
NASA Technical Reports Server (NTRS)
Spangenberg, D. B.
1986-01-01
Statolith formation in Cnidaria was reviewed with an emphasis on Aurelia statoliths. The review provides information on the chemical composition, mechanisms of initiation of mineralization, and effects of environmental factors on Cnidarian statolith formation. Environmental factors discussed included modified sea water ingredients, X-irradiation, clinostat rotation, and petroleum oil ingredients. A detailed account of the effects of cadmium on mineralization and demineralization of Aurelia statoliths is given. Cadmium at dosages of 2 to 4 micromoles significantly reduces statolith numbers in developing ephyrae. At a dosage of 3 micromoles, cadmium accelerates statolith loss in unfed ephyrae studied at 4 and 8 days following ephyrae release from strobilae. Cadmium, therefore, is shown to reduce statolith numbers in developing ephyrae and to cause greater reduction of statolith numbers in unfed ephyrae after 4 and 8 days than occurred in controls. Supplementation of Cd(2+)-containing artificial sea water (ASW) with calcium (3X and 5X ASW calcium content) results in higher numbers of statoliths at day 4 as compared with cadmium-treated ephyrae. At 8 days only the 5X calcium supplemented ASW is effective in enhancing statolith numbers in Cd(2+)-treated ephyrae. These results suggest that cadmium competes in some manner with calcium at the mineralizing sites of Aurelia.
NASA Astrophysics Data System (ADS)
Jamaluddin; Darwis, A.; Massinai, M. A.
2018-02-01
Asbuton as natural rock asphalt consists of a granular material; usually limestone or sandstone. In its natural state, it contains bitumen intimately dispersed throughout its mass, while the remainder of the material is a solid mineral matter. This research was conducted in Sorowalio, Buton Regency, Southeast Sulawesi province, Indonesia. This study aims to determine the content and the percentage of minerals contained in the rocks by using X-Ray Fluorescence (XRF). The method of research is a preliminary survey, sampling and laboratory analysis. XRF reports chemical composition, including Si (quartz) and Ca (calcite). The results indicate the content and the percentage of element dominate the rock sample is Fe2O3, MgO, CaO, and SiO2. Research results using XRF show that there are four metal oxide dominant elements. Hematite (Fe2O3) is dominant in all locations of sampling. Magnesium oxide (MgO) has the highest levels found in sample number six and the lowest is in sample number five. Silicates (SiO) has the highest levels at sample number six and the lowest in sample number seven. Calcium oxide (CaO) is dominant in all sampling locations. The sample of asbuton contains 37.90% asphalt, 43.28% carbonate, and18.82% other minerals.
Comparison of osteoporosis and calcium intake between Japan and the United States.
Fujita, T; Fukase, M
1992-06-01
The number of osteoporotic females in Japan with vertebral bone mineral density measured by dual energy x-ray absorptiometry, defined as less than -3 SD of the peak bone mass, is approximately 10,000,000, corresponding to 8% of the whole population of Japan. While this value approximately corresponds to the prevalence of low bone mineral density in the United States, the incidence of hip fracture appears to be much less in Japan than in the United States, 50,000 per 125,000,000 per year compared with 250,000 for a population twice as large. This seems to be paradoxical because of the lower bone mineral density and lower calcium intake in Japan, with 400-500 mg/day mainly as soybean products, small fish with bones, and vegetables. The difference in hip fracture incidence, however, may not actually be as wide as it seems when the larger number of bedridden elderly subjects in Japan is taken into consideration. In these bedridden subjects with severe immobilization osteoporosis, hip fracture is only prevented by the fact that they are not ambulatory. Life-style difference may also offer an explanation. Sitting on a tatami mattress on completely flexed knees with frequent standing up, along with other household work, in a narrow home space may ensure a marked development of hip musculature and also provide skill in balancing oneself to prevent fails. The difference in fracture incidence should be analyzed from various angles to obtain a firm ground for the future prevention of hip fracture due to osteoporosis. Although osteoporosis universally affects all races and nationalities, conspicuous differences may be encountered in the severity of its manifestations and complications.(ABSTRACT TRUNCATED AT 250 WORDS)
Jayalakshmi, S.; Platel, Kalpana
2016-01-01
Background & objectives: Iron supplementation is usually given to pregnant and lactating women who may also have marginal deficiency of zinc. The negative impact of supplemental iron and calcium on zinc status is a cause of concern. The present investigation was undertaken to examine the effect of inclusion of iron and calcium in the diet at supplementary levels on zinc status of experimental rats. Methods: Groups of experimental rats were maintained on diets supplemented with iron (Molar ratio - Zn:Fe 1:30) and calcium (Molar ratio - Zn:Ca 1:667) both individually and in combination for six weeks. Zinc status of these rats was assessed by determining zinc concentration in circulation and in organs, and the activities of zinc containing enzymes in serum and liver. Results: The zinc status of experimental rats receiving supplemental levels of iron and calcium was significantly compromised. Zinc concentration in serum, kidney, spleen and liver was reduced significantly by both these minerals. Six weeks of supplementation of iron and calcium individually, significantly reduced the activity of liver and serum superoxide dismutase and alkaline phosphatase. Activity of liver alcohol dehydrogenase was lowered in calcium supplemented group and in calcium + iron supplemented group, while that of carbonic anhydrase was significantly reduced by iron, calcium and their combination. Interpretation & conclusions: Supplemental levels of iron and calcium, both individually and in combination, significantly compromised the zinc status of experimental rats. This negative effect of these two minerals was more prominent when these were supplemented for a period of six weeks. PMID:27121523
Masumoto, Asuka; Sonou, Tomohiro; Ohya, Masaki; Yashiro, Mitsuru; Nakashima, Yuri; Okuda, Kouji; Iwashita, Yuko; Mima, Toru; Negi, Shigeo; Shigematsu, Takashi
2017-07-01
Vascular calcification (VC) is a risk factor of cardiovascular and all-cause mortality in patients with chronic kidney disease (CKD). CKD-mineral and bone metabolism disorder is an important problem in patients with renal failure. Abnormal levels of serum phosphate and calcium affect CKD-mineral and bone metabolism disorder and contribute to bone disease, VC, and cardiovascular disease. Hypercalcemia is a contributing factor in progression of VC in patients with CKD. However, the mechanisms of how calcium promotes intracellular calcification are still unclear. This study aimed to examine the mechanisms underlying calcium-induced calcification in a rat aortic tissue culture model. Aortic segments from 7-week-old male Sprague-Dawley rats were cultured in serum-supplemented medium for 10 days. We added high calcium (HiCa; calcium 3.0 mM) to high phosphate (HPi; phosphate 3.8 mM) medium to accelerate phosphate and calcium-induced VC. We used phosphonoformic acid and the calcimimetic R-568 to determine whether the mechanism of calcification involves Pit-1 or the calcium-sensing receptor. Medial VC was significantly augmented by HPi+HiCa medium compared with HPi alone (300%, p<0.05), and was associated with upregulation of Pit-1 protein. Pit-1 protein concentrations in HPi+HiCa medium were greater than those in HPi medium. Phosphonoformic acid completely negated the augmentation of medial VC induced by HPi+HiCa. R-568 had no additive direct effect on medial VC. These results indicated that exposure to HPi+HiCa accelerates medial VC, and this is mediated through Pit-1, not the calcium-sensing receptor.
Citrate bridges between mineral platelets in bone
Davies, Erika; Müller, Karin H.; Wong, Wai Ching; Pickard, Chris J.; Reid, David G.; Skepper, Jeremy N.; Duer, Melinda J.
2014-01-01
We provide evidence that citrate anions bridge between mineral platelets in bone and hypothesize that their presence acts to maintain separate platelets with disordered regions between them rather than gradual transformations into larger, more ordered blocks of mineral. To assess this hypothesis, we take as a model for a citrate bridging between layers of calcium phosphate mineral a double salt octacalcium phosphate citrate (OCP-citrate). We use a combination of multinuclear solid-state NMR spectroscopy, powder X-ray diffraction, and first principles electronic structure calculations to propose a quantitative structure for this material, in which citrate anions reside in a hydrated layer, bridging between apatitic layers. To assess the relevance of such a structure in native bone mineral, we present for the first time, to our knowledge, 17O NMR data on bone and compare them with 17O NMR data for OCP-citrate and other calcium phosphate minerals relevant to bone. The proposed structural model that we deduce from this work for bone mineral is a layered structure with thin apatitic platelets sandwiched between OCP-citrate–like hydrated layers. Such a structure can explain a number of known structural features of bone mineral: the thin, plate-like morphology of mature bone mineral crystals, the presence of significant quantities of strongly bound water molecules, and the relatively high concentration of hydrogen phosphate as well as the maintenance of a disordered region between mineral platelets. PMID:24706850
Pritchard, J.M.; Papaioannou, A.; Tomowich, C.; Giangregorio, L.M.; Atkinson, S.A.; Beattie, K.A.; Adachi, J.D.; DeBeer, J.; Winemaker, M.; Avram, V.; Schwarcz, H.P.
2016-01-01
Purpose The purpose of this study was to determine whether trabecular bone mineralization differed in adults with type 2 diabetes compared to adults without type 2 diabetes. Methods Proximal femur specimens were obtained following a total hip replacement procedure from men and women ≥65 years of age with and without type 2 diabetes. A scanning electron microscope was used for quantitative backscattered electron imaging (qBEI) analysis of trabecular bone samples from the femoral neck. Gray scale images (pixel size=5.6 μm2) were uploaded to ImageJ software and gray level (GL) values were converted to calcium concentrations (weight [wt] % calcium [Ca]) using data obtained with energy dispersive X-ray spectrometry. The following bone mineralization density distribution (BMDD) outcomes were collected: the weighted mean bone calcium concentration (CaMEAN), the most frequently occurring bone calcium concentration (CaPEAK) and mineralization heterogeneity (CaWIDTH). Differences between groups were assessed using the Student’s t-test for normally distributed data and Mann–Whitney U-test for non-normally distributed data. An alpha value of <0.05 was considered significant. Results Thirty-five Caucasian participants were recruited (mean [standard deviation, SD] age, 75.5 [6.5] years): 14 adults with type 2 diabetes (years since type 2 diabetes diagnosis, 13.5 [7.4] years) and 21 adults without type 2 diabetes. In the adults with type 2 diabetes, bone CaMEAN was 4.9% greater (20.36 [0.98] wt.% Ca versus 19.40 [1.07] wt.% Ca, p=0.015) and CaWIDTH was 9.4% lower (median [interquartile range] 3.55 [2.99–4.12] wt.% Ca versus 3.95 [0.71] wt.% Ca, p<0.001) compared to controls. There was no between-group difference in CaPEAK (21.12 [0.97] wt.% Ca for type 2 diabetes versus 20.44 [1.30] wt.% Ca for controls, p=0.121). Conclusion The combination of elevated mean calcium concentration in bone and lower mineralization heterogeneity in adults with type 2 diabetes may have deleterious effects on the biomechanical properties of bone. These microscopic alterations in bone mineralization, which may be mediated by suppressed bone remodeling, further elucidate higher fracture risk in adults with type 2 diabetes. PMID:23356988
21 CFR 582.80 - Trace minerals added to animal feeds.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Cobalt Cobalt acetate. Cobalt carbonate. Cobalt chloride. Cobalt oxide. Cobalt sulfate. Copper Copper... pyrophosphate. Copper sulfate. Iodine Calcium iodate. Calcium iodobehenate. Cuprous iodide. 3,5-Diiodosalicylic.... Thymol iodide. Iron Iron ammonium citrate. Iron carbonate. Iron chloride. Iron gluconate. Iron oxide...
21 CFR 582.80 - Trace minerals added to animal feeds.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Cobalt Cobalt acetate. Cobalt carbonate. Cobalt chloride. Cobalt oxide. Cobalt sulfate. Copper Copper... pyrophosphate. Copper sulfate. Iodine Calcium iodate. Calcium iodobehenate. Cuprous iodide. 3,5-Diiodosalicylic.... Thymol iodide. Iron Iron ammonium citrate. Iron carbonate. Iron chloride. Iron gluconate. Iron oxide...
21 CFR 582.80 - Trace minerals added to animal feeds.
Code of Federal Regulations, 2013 CFR
2013-04-01
... Cobalt Cobalt acetate. Cobalt carbonate. Cobalt chloride. Cobalt oxide. Cobalt sulfate. Copper Copper... pyrophosphate. Copper sulfate. Iodine Calcium iodate. Calcium iodobehenate. Cuprous iodide. 3,5-Diiodosalicylic.... Thymol iodide. Iron Iron ammonium citrate. Iron carbonate. Iron chloride. Iron gluconate. Iron oxide...
The Effects of IGFBP3 Induction by TFG-B in Breast Tumorigenesis
2000-09-01
of differentiation inducing media. This media contains P3-glycerolphosphate to facilitate mineral deposistion and ascorbic acid to facilitate collagen...collagenase to isolate osteoblasts. These isolated primary osteoblasts express differentiation markers such as osteocalcin and will form calcium nodules in...a synthetic peptide of a parathyroid hormone-related protein on calcium homeostasis, renal tubular calcium reabsorption, and bone metabolism in vivo
Process for detoxifying coal tars
Longwell, John P.; Peters, William A.
1983-01-01
A process for treating liquid hydrocarbons to remove toxic, mutagenic and/or carcinogenic aromatic hydrocarbons comprises feeding the hydrocarbons into a reactor where vapors are thermally treated in contact with a catalyst consisting essentially of calcium oxide or a calcium oxide containing mineral. Thermally treating liquid hydrocarbons in contact with calcium oxide preferentially increases the cracking of aromatics thus producing a product having a reduced amount of aromatic compounds.
Experimental study of terrestrial plant litter interaction with aqueous solutions
NASA Astrophysics Data System (ADS)
Fraysse, F.; Pokrovsky, O. S.; Meunier, J.-D.
2010-01-01
Quantification of silicon and calcium recycling by plants is hampered by the lack of physico-chemical data on reactivity of plant litter in soil environments. We applied a laboratory experimental approach for determining the silica and calcium release rates from litter of typical temperate and boreal plants: pine ( Pinus laricio), birch ( Betula pubescens), larch ( Larix gmelinii), elm ( Ulmus laevis Pall.), tree fern ( Dicksonia squarrosa), and horsetail (Equisetum arvense) in 0.01 M NaCl solutions, pH of 2-10 and temperature equals to 5, 25 and 40 °C. Open system, mixed-flow reactors equipped with dialysis compartment and batch reactors were used. Comparative measurements were performed on intact larch needles and samples grounded during different time, sterilized or not and with addition or not of sodium azide in order to account for the effect of surface to mass ratio and possible microbiological activity on the litter dissolution rates. Litter degradation results suggest that the silica release rate is independent on dissolved organic carbon release (cell breakdown) which implies the presence of phytoliths in a pure "inorganic" pool not complexed with organic matter. Calcium and DOC are released at the very first stage of litter dissolution while Si concentration increases gradually suggesting the presence of Ca and Si in two different pools. The dry-weight normalized dissolution rate at circum-neutral pH range (approx. 1-10 μmol/g DW/day) is 2 orders of magnitude higher than the rates of Si release from common soil minerals (kaolinite, smectite, illite). Minimal Ca release rates evaluated from batch and mixed-flow reactors are comparable with those of most reactive soil minerals such as calcite and apatite, and several orders of magnitude higher than the dissolution rates of major rock-forming silicates (feldspars, pyroxenes). The activation energy for Si liberation from plant litter is approx. 50 kJ/mol which is comparable with that of surface-controlled mineral dissolutions. It is shown that the Si release rate from the above-ground forest biomass is capable of producing the Si concentrations observed in soil solutions of surficial horizons and contribute significantly to the Si flux from the soil to the river.
The origin of high sodium bicarbonate waters in the Atlantic and Gulf Coastal Plains
Foster, M.D.
1950-01-01
Some sodium bicarbonate waters at depth in the Atlantic and Gulf Coastal Plains have the same bicarbonate content as the shallower calcium bicarbonate waters in the same formation and appear to be the result of replacement of calcium by sodium through the action of base-exchange minerals. Others, however, contain several hundred parts per million more of bicarbonate than any of the calcium bicarbonate waters and much more bicarbonate than can be attributed to solution of calcium carbonate through the action of carbon dioxide derived from the air and soil. As the waters in the Potomac group (Cretaceous) are all low in sulphate and as the environmental conditions under which the sediments of the Potomac group were deposited do not indicate that large amounts of sulphate are available for solution, it does not seem probable that carbon dioxide generated by chemical or biochemical breakdown of sulphate is responsible for the high sodium bicarbonate waters in this area. Sulphate as a source of oxygen is not necessary for the generation of carbon dioxide by carbonaceous material. Oxygen is an important constituent of carbonaceous material and carbon dioxide is a characteristic decomposition product of such material-as, for example, peat and lignite. Experimental work showed that distilled water, calcium bicarbonate water, and sodium bicarbonate water, after contact with lignite, calcium carbonate, and permutite (a base-exchange material), had all increased greatly in sodium bicarbonate content and had become similar in chemical character and in mineral content to high sodium bicarbonate waters found in the Coastal Plain. The tests indicated that carbonaceous material can act as a source of carbon dioxide, which, when dissolved in water, enables it to take into solution more calcium carbonate. If base-exchange materials are also present to replace calcium with sodium, a still greater amount of bicarbonate can be held in solution. The presence of carbonaceous material, together with calcium carbonate and base-exchange minerals in a formation is, therefore, sufficient to account for the occurrence in it of high sodium bicarbonate waters. ?? 1950.
NASA Technical Reports Server (NTRS)
Muirhead, Dean; Carrier, Christopher
2012-01-01
In this study, three different mineral acids were substituted for sulfuric acid (H2SO4) in the urine stabilizer solution to eliminate the excess of sulfate ions in pretreated urine and assess the impact on maximum water recovery to avoid precipitation of minerals during distillation. The study evaluated replacing 98% sulfuric acid with 85% phosphoric acid (H3PO4), 37% hydrochloric acid (HCl), or 70% nitric acid (HNO3). The effect of lowering the oxidizer concentration in the pretreatment formulation also was studied. This paper summarizes the test results, defines candidate formulations for further study, and specifies the injection masses required to stabilize urine and minimize the risk of mineral precipitation during distillation. In the first test with a brine ersatz acidified with different acids, the solubility of calcium in gypsum saturated solutions was measured. The solubility of gypsum was doubled in the brines acidified with the alternative acids compared to sulfuric acid. In a second series of tests, the alternative acid pretreatment concentrations were effective at preventing precipitation of gypsum and other minerals up to 85% water recovery from 95th-percentile pretreated, augmented urine. Based on test results, phosphoric acid is recommended as the safest alternative to sulfuric acid. It also is recommended that the injected mass concentration of chromium trioxide solution be reduced by 75% to minimize liquid resupply mass by about 50%, reduce toxicity of brines, and reduce the concentration of organic acids in distillate. The new stabilizer solution formulations and required doses to stabilize urine and prevent precipitation of minerals up to 85% water recovery are given. The formulations in this study were tested on a limited number of artificially augmented urine batches collected from employees at the Johnson Space Center (JSC). This study successfully demonstrated that the desired physical and chemical stability of pretreated urine and brines can be achieved using alternate pretreatment formulations under laboratory conditions. Additional testing and hazard assessments will be required to determine the feasibility of utilizing the proposed urine pretreatment formulations on ISS.
Drinking water constituents and disease.
Rylander, Ragnar
2008-02-01
Several epidemiological investigations over the last 50 y have demonstrated a relation between risk for cardiovascular disease and drinking water hardness or its content of magnesium and calcium. An additional parameter, first suggested in a study from Japan 50 y ago, is the acidity of the water. It is known that acid load influences the reabsorption of calcium and magnesium in the renal tubuli. Intervention studies have shown that acid-base conditions influence the homeostasis of minerals. Data from intervention studies using magnesium, calcium, and hydrogen carbonate are reviewed. It is suggested that the health effects related to drinking water found in some studies may be caused by an increased urinary excretion of minerals induced by acid conditions in the body and that drinking water should contain sufficient amounts of hydrogen carbonate to prevent this effect.
He, Chuanglong; Jin, Xiaobing; Ma, Peter X.
2013-01-01
Mineralized nanofibrous scaffolds have been proposed as promising scaffolds for bone regeneration due to their ability to mimic both nanoscale architecture and chemical composition of natural bone extracellular matrix (ECM). In this study, a novel electrodeposition method was compared with an extensively explored simulated body fluid (SBF) incubation method in terms of the deposition rate, chemical composition, and morphology of calcium phosphate formed on electrospun fibrous thin matrices with a fiber diameter in the range from about 200 nm to about 1400 nm prepared using 6, 8, 10 and 12 wt% poly(l-lactic acid) (PLLA) solutions in a mixture of dichloromethane and acetone (2:1 in volume). The effects of the surface modification using the two mineralization techniques on osteoblastic cell (MC3T3-E1) proliferation and differentiation were also examined. It was found that electrodeposition was two to three orders of magnitude faster than the SBF method in mineralizing the fibrous matrices, reducing the mineralization time from about two weeks to an hour to achieve the same amounts of mineralization. The mineralization rate also varied with the fiber diameter but in opposite directions between the two mineralization methods. As a general trend, the increase of fiber diameter resulted in a faster mineralization rate for the electrodeposition method but a slower mineralization rate for the SBF incubation method. Using the electrodeposition method, one can control the chemical composition and morphology of the calcium phosphate by varying the electric deposition potential and electrolyte temperature to tune the mixture of dicalcium phosphate dihydrate (DCPD) and hydroxy apatite (HAp). Using the SBF method, one can only obtain a low crystallinity HAp. The mineralized electrospun PLLA fibrous matrices from either method similarly facilitate the proliferation and osteogenic differentiation of preosteoblastic MC3T3-E1 cells as compared to neat PLLA matrices. Therefore, the electrodeposition method can be utilized as a fast and versatile technique to fabricate mineralized nanofibrous scaffolds for bone tissue engineering. PMID:24012605
Bone health status and lipid profile among post-menopausal malay women in Cheras, Kuala Lumpur.
Hasnah, H; Amin, I; Suzana, S
2012-08-01
A cross-sectional study was conducted to determine bone health status and nutrient intakes among post-menopausal women residing in low cost houses in Cheras, Kuala Lumpur. A total of 125 subjects aged 60 +/- 4 years who had attained menopause at age 50 +/- 5 years participated in this study. Subjects' weight and height were measured and calculated for body mass index (BMI). They were also assessed for bone health status using the Quantitative Ultrasound (QUS). Nutrient intake was assessed using a dietary history Questionnaire. Fasting serum lipid and blood pressure measurements were also taken. The majority of the subjects were overweight and obese (80%) based on BMI status. Calcaneal measurements using the QUS indicated that while 57% or the subjects had normal bone mineral density, 37% were osteopenic and 6% osteoporotic. Calcium intake of the subjects was 505 +/- 263 mg /day, which is only 50% of the Malaysian Recommended Nutrient Intake for calcium (1000 mg/d). About 74% of the subjects were hypercholesterolemic and 58% were hypertriglyceridemic. Two-thirds reported that they were taking medication for hypertension, diabetes mellitus and heart disease. The results showed low health and nutritional status among post-menopausal women living in low-cost flats in Kuala Lumpur. They have low bone mass which may be due to their predominantly non-milk based diets which places them at high risk of hip fractures. Apart from milk, other food sources of calcium, including soya bean products such as 'tempeh' and healthy ways of cooking should be recommended to older people.
Park, S M; Joung, J Y; Cho, Y Y; Sohn, S Y; Hur, K Y; Kim, J H; Kim, S W; Chung, J H; Lee, M K; Min, Y-K
2015-03-01
High salt intake is a well-recognized risk factor of osteoporosis for its modulating effect on calcium metabolism. To understand the effect of dietary sodium on bone turnover, we evaluated the association between urinary sodium excretion and bone turnover markers in Korean postmenopausal women with low bone mass. A retrospective review of medical records at a single institution identified 537 postmenopausal women who were first diagnosed with osteopenia or osteoporosis between 2008 and 2013. Subjects were stratified by low (<2 g/day, n=77), moderate (2-4.4 g/day, n=354) and high (⩾4.4 g/day, n=106) sodium excretion. A 24-h urine was collected to estimate sodium, calcium and creatinine. Bone turnover markers and calciotropic hormones were measured in serum. Bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry. Sodium intake was positively associated with urinary sodium excretion (P=0.006, r=0.29). Bone turnover markers were significantly higher in the moderate-to-high urinary sodium excretion group (⩾2 g/day) than in the low urinary sodium excretion group (<2 g/day); CTX-I (C-telopeptides of type I collagen) was 21.3% higher (P=0.001) and osteocalcin (OC) was 15.7% higher (P=0.004). Calciotropic hormones and BMD were not significantly different across the sodium excretion groups. High urinary sodium excretion (⩾2 g/day) increased bone turnover markers in Korean postmenopausal women, suggesting that excessive sodium intake might accelerate bone turnover.
Li, Qiaoli; LaRusso, Jennifer; Grand‐Pierre, Alix E.; Uitto, Jouni
2009-01-01
Abstract Pseudoxanthoma elasticum (PXE) is a heritable disorder characterized by ectopic mineralization of connective tissues primarily in the skin, eyes, and the cardiovascular system. PXE is caused by mutations in the ABCC6 gene. While PXE is associated with considerable morbidity and mortality, there is currently no effective or specific treatment. In this study, we tested oral phosphate binders for treatment of a mouse model of PXE which we have developed by targeted ablation of the corresponding mouse gene (Abcc6 −/−). This “knock‐out” (KO) mouse model recapitulates features of PXE and demonstrates mineralization of a number of tissues, including the connective tissue capsule surrounding vibrissae in the muzzle skin which serves as an early biomarker of the mineralization process. Treatment of these mice with a magnesium carbonate‐enriched diet (magnesium concentration being 5‐fold higher than in the control diet) completely prevented mineralization of the vibrissae up to 6 months of age, as demonstrated by computerized morphometric analysis of histopathology as well as by calcium and phosphate chemical assays. The magnesium carbonate‐enriched diet also prevented the progression of mineralization when the mice were placed on that experimental diet at 3 months of age and followed up to 6 months of age. Treatment with magnesium carbonate was associated with a slight increase in the serum concentration of magnesium, with no effect on serum calcium and phosphorus levels. In contrast, concentration of calcium in the urine was increased over 10‐fold while the concentration of phosphorus was markedly decreased, being essentially undetectable after long‐term (>4 month) treatment. No significant changes were noted in the serum parathyroid hormone levels. Computerized axial tomography scan of bones in mice placed on magnesium carbonate‐enriched diet showed no differences in the bone density compared to mice on the control diet, and chemical assays showed a small increase in the calcium and phosphate content of the femurs by chemical assay, in comparison to mice on control diet. Similar experiments with another experimental diet supplemented with lanthanum carbonate did not interfere with the mineralization process in Abcc6 −/− mice. These results suggest that magnesium carbonate may offer a potential treatment modality for PXE, a currently intractable disease, as well as for other conditions characterized by ectopic mineralization of connective tissues. PMID:20443931
Li, Qiaoli; Larusso, Jennifer; Grand-Pierre, Alix E; Uitto, Jouni
2009-12-01
Pseudoxanthoma elasticum (PXE) is a heritable disorder characterized by ectopic mineralization of connective tissues primarily in the skin, eyes, and the cardiovascular system. PXE is caused by mutations in the ABCC6 gene. While PXE is associated with considerable morbidity and mortality, there is currently no effective or specific treatment. In this study, we tested oral phosphate binders for treatment of a mouse model of PXE which we have developed by targeted ablation of the corresponding mouse gene (Abcc6(-/-)). This "knock-out" (KO) mouse model recapitulates features of PXE and demonstrates mineralization of a number of tissues, including the connective tissue capsule surrounding vibrissae in the muzzle skin which serves as an early biomarker of the mineralization process. Treatment of these mice with a magnesium carbonate-enriched diet (magnesium concentration being 5-fold higher than in the control diet) completely prevented mineralization of the vibrissae up to 6 months of age, as demonstrated by computerized morphometric analysis of histopathology as well as by calcium and phosphate chemical assays. The magnesium carbonate-enriched diet also prevented the progression of mineralization when the mice were placed on that experimental diet at 3 months of age and followed up to 6 months of age. Treatment with magnesium carbonate was associated with a slight increase in the serum concentration of magnesium, with no effect on serum calcium and phosphorus levels. In contrast, concentration of calcium in the urine was increased over 10-fold while the concentration of phosphorus was markedly decreased, being essentially undetectable after long-term (> 4 month) treatment. No significant changes were noted in the serum parathyroid hormone levels. Computerized axial tomography scan of bones in mice placed on magnesium carbonate-enriched diet showed no differences in the bone density compared to mice on the control diet, and chemical assays showed a small increase in the calcium and phosphate content of the femurs by chemical assay, in comparison to mice on control diet. Similar experiments with another experimental diet supplemented with lanthanum carbonate did not interfere with the mineralization process in Abcc6(-/-) mice. These results suggest that magnesium carbonate may offer a potential treatment modality for PXE, a currently intractable disease, as well as for other conditions characterized by ectopic mineralization of connective tissues.
Langlois, C; Simon, L; Lécuyer, Ch
2003-12-01
A time-dependent box model is developed to calculate oxygen isotope compositions of bone phosphate as a function of environmental and physiological parameters. Input and output oxygen fluxes related to body water and bone reservoirs are scaled to the body mass. The oxygen fluxes are evaluated by stoichiometric scaling to the calcium accretion and resorption rates, assuming a pure hydroxylapatite composition for the bone and tooth mineral. The model shows how the diet composition, body mass, ambient relative humidity and temperature may control the oxygen isotope composition of bone phosphate. The model also computes how bones and teeth record short-term variations in relative humidity, air temperature and delta18O of drinking water, depending on body mass. The documented diversity of oxygen isotope fractionation equations for vertebrates is accounted for by our model when for each specimen the physiological and diet parameters are adjusted in the living range of environmental conditions.
Review of the biological effects of weightlessness on the human endocrine system
NASA Technical Reports Server (NTRS)
Hughes-Fulford, M.
1993-01-01
Studies from space flights over the past two decades have demonstrated that there are basic physiological changes in humans during space flight. These changes include cephalad fluid shifts, loss of fluid and electrolytes, loss of muscle mass, space motion sickness, anemia, reduced immune response, and loss of calcium and mineralized bone. The cause of most of these manifestations is not known but the general approach has been to investigate systemic and hormonal changes. However, data from the 1973-1974 Skylabs, Spacelab 3 (SL-3), Spacelab D-I (SL-DI), and now the new SLS-1 missions support a more basic biological response to microgravity that may occur at the tissue, cellular, and molecular level. This report summarizes ground-based and SLS-1 experiments that examined the mechanism of loss of red blood cell mass in humans, the loss of bone mass and lowered osteoblast growth under space flight conditions, and loss of immune function in microgravity.
Chapter 7:Mineral Scale Management
Alan W. Rudie; Peter W. Hart
2012-01-01
Mineral scale problems are not new to pulp mills and bleach plants. The liquor recovery system ensures that white liquor is saturated in calcium carbonate, and this mineral will precipitate when heated to cooking temperatures in the digester [1,2]. The original single-vessel continuous digesters sold by Kamyr had an extra liquor heater as standard equipment to enable...
Characterization of Biogenic Gas and Mineral Formation Process by Denitrification in Porous Media
NASA Astrophysics Data System (ADS)
Hall, C. A.; Kim, D.; Mahabadi, N.; van Paassen, L. A.
2017-12-01
Biologically mediated processes have been regarded and developed as an alternative approach to traditional ground improvement techniques. Denitrification has been investigated as a potential ground improvement process towards liquefaction hazard mitigation. During denitrification, microorganisms reduce nitrate to dinitrogen gas and facilitate calcium carbonate precipitation as a by-product under adequate environmental conditions. The formation of dinitrogen gas desaturates soils and allows for potential pore pressure dampening during earthquake events. While, precipitation of calcium carbonate can improve the mechanical properties by filling the voids and cementing soil particles. As a result of small changes in gas and mineral phases, the mechanical properties of soils can be significantly affected. Prior research has primarily focused on quantitative analysis of overall residual calcium carbonate mineral and biogenic gas products in lab-scale porous media. However, the distribution of these products at the pore-scale has not been well-investigated. In this research, denitrification is activated in a microfluidic chip simulating a homogenous pore structure. The denitrification process is monitored by sequential image capture, where gas and mineral phase changes are evaluated by image processing. Analysis of these images correspond with previous findings, which demonstrate that biogenic gas behaviour at the pore scale is affected by the balance between reaction, diffusion, and convection rates.
NASA Astrophysics Data System (ADS)
Heger, Michal; Mordon, Serge R.; Leroy, Gérard; Fleurisse, Laurence; Creusy, Collette
2006-03-01
Laser-assisted cartilage reshaping (LACR) is a relatively novel technique designed to noninvasively and permanently restructure cartilaginous tissue. It is believed that heat-induced stress relaxation, in which a temperature-mediated disruption of H2O binding is associated with conformational alterations in the proteoglycan and collagen-rich matrix, constitutes the underlying mechanism of LACR. Several reports have suggested that laser-mediated cartilage mineralization may contribute to the permanent shape change of laser-reshaped cartilage. In an effort to validate these results in the context of Er:glass LACR, we performed a preliminary Raman microspectrometric study to characterize the crystal deposits in laser-irradiated chondrocytes and extracellular matrix. For the first time, we identified intracellular calcium sulfate deposits and extracellular calcium phosphate (apatite) crystals in laser-reshaped rabbit auricular cartilage. Calcium carbonate deposits are localized in both irradiated and nonirradiated samples, suggesting that this mineral plays no role in conformational retention. In our discussion, we elaborate on the possible molecular and cellular mechanisms responsible for intra- and extracellular crystallization, and propose a novel hypothesis on the formation of apatite, inasmuch as the biological function of this mineral (providing structure and rigidity in bones and dental enamel) may be extrapolated to the permanent shape change of laser-irradiated cartilage.
Mineral content of complementary foods.
Jani, Rati; Udipi, S A; Ghugre, P S
2009-01-01
To document mineral contents iron, zinc, calcium, energy contents and nutrient densities in complementary foods commonly given to young urban slum children. Information on dietary intake was collected from 892 mothers of children aged 13-24 months, using 24 hour dietary recall and standardized measures. Three variations of 27 most commonly prepared recipes were analyzed and their energy (Kcal/g) and nutrient densities (mg/100 Kcal) were calculated. Considerable variations were observed in preparation of all items fed to the children. Cereal-based items predominated their diets with only small amount of vegetables/fruits. Fenugreek was the only leafy vegetable included, but was given to only 1-2% of children. Iron, calcium, zinc contents of staple complementary foods ranged from: 0.33 mg to 3.73 mg, 4 mg to 64 mg, and 0.35 mg to 2.99 mg/100 respectively. Recipes diluted with less water and containing vegetables, spices had higher mineral content. Minerals densities were higher for dals, fenugreek vegetable, khichdi and chapatti. Using the median amounts of the various recipes fed to children, intakes of all nutrients examined especially calcium and iron was low. There is an urgent need to educate mothers about consistency, dilution, quantity, frequency, method of preparation, inclusion of micronutrient-rich foods, energy-dense complementary foods and gender equality.
Mineralization of the Sea Urchin Skeleton
NASA Astrophysics Data System (ADS)
Wilt, F.
2001-12-01
The sea urchin possess a calcareous skeleton composed of over 99% magnesian calcite,an enveloping extracellular matrix, and an occluded protein matrix. The most intensively studied skeletal element is the spicule of the embryo. At the 32 cell stage of development a cohort of 4 cells becomes irrevocably dedicated to spicule formation. At the early gastrula stage the descendants of these founder cells form the primary mesenchyme (PMC). The PMCs fuse to form a multinucleated syncytium connected by cytoplasmic cables, and the calcitic skeleton is formed within these cables. Our primary concern is with the cellular and molecular mechanisms that support the formation of the mineralized spicules. The import of calcium into the PMCs results in appearance of intracellular vesicles containing precipitated calcium, which is neither very stable nor birefringent, and could be amorphous. The precipitated calcium is vectorially secreted into an extracellular space. This space is almost completely enclosed by cytoplasmic strands, and the mineral is encased in an extracellular matrix. Proteins destined for the extracellular matrix, and for inclusion in the spicule, are present in the Golgi membranes and in small intracellular vesicles. These vesicles apparently deliver the matrix proteins to the growing spicule. Our current view is that the matrix molecules are much more than a passive armature, but are actively involved in precipitation, secretion, and organization of the mineral phase.
Veghte, Daniel P; Freedman, Miriam A
2012-11-06
It is currently unknown whether mineral dust causes a net warming or cooling effect on the climate system. This uncertainty stems from the varied and evolving shape and composition of mineral dust, which leads to diverse interactions of dust with solar and terrestrial radiation. To investigate these interactions, we have used a cavity ring-down spectrometer to study the optical properties of size-selected calcium carbonate particles, a reactive component of mineral dust. The size selection of nonspherical particles like mineral dust can differ from spherical particles in the polydispersity of the population selected. To calculate the expected extinction cross sections, we use Mie scattering theory for monodisperse spherical particles and for spherical particles with the polydispersity observed in transmission electron microscopy images. Our results for calcium carbonate are compared to the well-studied system of ammonium sulfate. While ammonium sulfate extinction cross sections agree with Mie scattering theory for monodisperse spherical particles, the results for calcium carbonate deviate at large and small particle sizes. We find good agreement for both systems, however, between the calculations performed using the particle images and the cavity ring-down data, indicating that both ammonium sulfate and calcium carbonate can be treated as polydisperse spherical particles. Our results indicate that having an independent measure of polydispersity is essential for understanding the optical properties of nonspherical particles measured with cavity ring-down spectroscopy. Our combined spectroscopy and microscopy techniques demonstrate a novel method by which cavity ring-down spectroscopy can be extended for the study of more complex aerosol particles.
Mazouri, Ali; Khosravi, Nastaran; Bordbar, Arash; Khalesi, Nasrin; Saboute, Maryam; Taherifard, Pegah; Mirzababaee, Marjan; Ebrahimi, Mehran
2017-06-01
The use of parenteral nutritional supplementation of phosphorus may lead to exhibit higher plasma phosphate concentrations and less radiological features in premature neonates susceptible to osteopenia. The present study aimed to assess the beneficial effects of adding intravenous phosphorus to total parenteral nutrition (TPN) on calcium and phosphorus metabolism in preterm neonates by measuring bone mineral content. This open-labeled randomized clinical trial was conducted on premature neonates who were hospitalized at NICU. The neonates were randomly assigned to two groups received TPN with intravenous sodium glycerophosphate or Glycophos (1.5 mmol/kg/day) or TPN without sodium glycerophosphate. At the end of the four weeks of treatment, the presence of osteopenia was examined using DEXA Scan. After completing treatment protocols, the group received TPN with intravenous Glycophos had significantly lower serum alkaline phosphatase (360±60 versus 762±71, P<0.001), as well as higher serum calcium to creatinine ratio (1.6±0.3 versus 0.44±0.13, P<0.001) compared to the control group received TPN without Glycophos. Those who received TPN with intravenous Glycophos experienced more increase in bone mineral density than those in control group (0.13±0.01 versus 0.10±0.02, P<0.001). There was no significant difference in serum calcium and serum vitamin D between the case and control groups. Adding intravenous sodium glycerophosphate to TPN in premature neonates can compensate the lack of bone mineral content and help to prevent osteopenia.
Datta, Mridul; Schwartz, Gary G.
2013-01-01
An unintended consequence of breast cancer therapies is an increased risk of osteoporosis due to accelerated bone loss. We conducted a systematic review of calcium and/or vitamin D (Ca±D) supplementation trials for maintaining bone mineral density (BMD) in women with breast cancer using the “before-after” data from the Ca±D supplemented comparison group of trials evaluating the effect of drugs such as bisphosphonates on BMD. Whether Ca±D supplements increase BMD in women undergoing breast cancer therapy has never been tested against an unsupplemented control group. However, results from 16 trials indicate that the Ca±D doses tested (500-1500 mg calcium; 200-1000 IU vitamin D) were inadequate to prevent BMD loss in these women. Cardiovascular disease is the main cause of mortality in women with breast cancer. Because calcium supplements may increase cardiovascular disease risk, future trials should evaluate the safety and efficacy of Ca±D supplementation in women undergoing breast cancer therapy. PMID:23932583
NASA Technical Reports Server (NTRS)
Schneider, V. S.; Hulley, S. B.; Donaldson, C. L.; Vogel, J. M.; Rosen, S. N.; Hantman, D. A.; Lockwood, D. R.; Seid, D.; Hyatt, K. H.; Jacobson, L. B.
1974-01-01
The phenomenon of calcium loss during bed rest was found to be analogous to the loss of bone material which occurs in the hypogravic environment of space flight. Ways of preventing this occurrence are investigated. A group of healthy adult males underwent 24-30 weeks of continuous bed rest. Some of them were given an exercise program designed to resemble normal ambulatory activity; another subgroup was fed supplemental potassium phosphate. The results from a 12-week period of treatment were compared with those untreated bed rest periods. The potassium phosphate supplements prevented the hypercalciuria of bed rest, but fecal calcium tended to increase. The exercise program did not diminish the negative calcium balance. Neither treatment affected the heavy loss of mineral from the calcaneus. Several additional studies are developed to examine the problem further.
Jarjou, L M A; Goldberg, G R; Coward, W A; Prentice, A
2012-06-01
There is a paucity of information from developing countries on total calcium intake during infancy, and potential consequences for growth and bone development. Observational longitudinal study of rural Gambian infants (13 males and 17 females) at 3 and 12 months of age. Breast-milk intake and calcium concentration, weighed dietary intake, anthropometry, midshaft radius bone mineral content (BMC) and bone width (BW). At 3 and 12 months (mean ± s.d.) calcium intake from breast milk was 179 ± 53 and 117 ± 38, and from other foods 12 ± 38 and 73 ± 105 mg/day. There was no difference in total calcium intake; 94% and 62% of calcium came from breast milk. At 3 and 12 months, weight s.d.-scores were -0.441 ± 1.07 and -1.967 ± 1.06; length s.d.-scores were -0.511 ± 1.04 and -1.469 ± 1.13. Breast-milk calcium intake positively predicted weight (P = 0.0002, P ≤ 0.0001) and length (P = 0.056, P = 0.001). These relationships were not independent of breast-milk intake, which positively predicted weight (P ≤ 0.002) and length (P = 0.06, P = 0.004). At 3, but not 12 months, weight and length correlated with total calcium intake. There were no relationships between total calcium intake and breast-milk intake with BW or BMC. The combination of low calcium intake from breast milk and complementary foods resulted in a low total calcium intake close to the estimated biological requirement for bone mineral accretion. Relationships between calcium intake and growth were largely accounted for by breast-milk intake, suggesting that low calcium intake per se was not the limiting factor in the poor growth. These findings have potential implications for deriving calcium requirements in developing countries.
Maditz, Kaitlin H; Smith, Brenda J; Miller, Matthew; Oldaker, Chris; Tou, Janet C
2015-02-10
Polycystic kidney disease (PKD), a genetic disorder characterized by multiple cysts and renal failure at an early age. In children, kidney disease is often accompanied by disordered mineral metabolism, failure to achieve peak bone mass, and reduced adult height. Optimizing bone health during the growth stage may preserve against bone loss associated with early renal dysfunction in PKD. Dietary soy protein and omega-3 polyunsaturated fatty acid (n-3 PUFA) have been reported to ameliorate PKD and to promote bone health. The study objective was to determine the bone effects of feeding soy protein and/or n-3 PUFAs in a rat model of PKD. Weanling female PCK rats (n = 12/group) were randomly assigned to casein + corn oil (Casein + CO), casein + soybean oil (Casein + SO), soy protein isolate + soybean oil (SPI + SO) or soy protein isolate + 1:1 soybean oil:salmon oil blend (SPI + SB) for 12 weeks. Rats fed SPI + SO diet had shorter (P = 0.001) femur length than casein-fed rats. Rats fed SPI + SO and SPI + SB diet had higher (P = 0.04) calcium (Ca) and phosphorus (P) retention. However, there were no significant differences in femur and tibial Ca, P or bone mass between diet groups. There were also no significant difference in bone microarchitecture measured by micro-computed tomography or bone strength determined by three-point bending test between diet groups. Early diet management of PKD using SPI and/or n-3 PUFAs influenced bone longitudinal growth and mineral balance, but neither worsened nor enhanced bone mineralization, microarchitecture or strength.
McCollough, Cynthia H; Ulzheimer, Stefan; Halliburton, Sandra S; Shanneik, Kaiss; White, Richard D; Kalender, Willi A
2007-05-01
To develop a consensus standard for quantification of coronary artery calcium (CAC). A standard for CAC quantification was developed by a multi-institutional, multimanufacturer international consortium of cardiac radiologists, medical physicists, and industry representatives. This report specifically describes the standardization of scan acquisition and reconstruction parameters, the use of patient size-specific tube current values to achieve a prescribed image noise, and the use of the calcium mass score to eliminate scanner- and patient size-based variations. An anthropomorphic phantom containing calibration inserts and additional phantom rings were used to simulate small, medium-size, and large patients. The three phantoms were scanned by using the recommended protocols for various computed tomography (CT) systems to determine the calibration factors that relate measured CT numbers to calcium hydroxyapatite density and to determine the tube current values that yield comparable noise values. Calculation of the calcium mass score was standardized, and the variance in Agatston, volume, and mass scores was compared among CT systems. Use of the recommended scanning parameters resulted in similar noise for small, medium-size, and large phantoms with all multi-detector row CT scanners. Volume scores had greater interscanner variance than did Agatston and calcium mass scores. Use of a fixed calcium hydroxyapatite density threshold (100 mg/cm(3)), as compared with use of a fixed CT number threshold (130 HU), reduced interscanner variability in Agatston and calcium mass scores. With use of a density segmentation threshold, the calcium mass score had the smallest variance as a function of patient size. Standardized quantification of CAC yielded comparable image noise, spatial resolution, and mass scores among different patient sizes and different CT systems and facilitated reduced radiation dose for small and medium-size patients.
Woodard, James C.
1971-01-01
Nephrocalcinosis occurred in weanling female rats fed a semipurified diet for 8 weeks. Mineralization of the inner cortex began after 3 weeks on the semipurified diet, and was most severe after 8 weeks. Intraluminal calcification was observed first in the pars recta of the proximal convoluted tubule; calcification of cytoplasmic organelles or basement membranes of the tubular epithelium was not observed. At the end of 8 weeks, some mineral deposits were seen within Henle's loops of the outer medulla. Histochemical studies demonstrated that the deposits contained calcium and phosphorus and had a glycoprotein matrix; electron diffraction studies indicated that the main mineral phase was hydroxyapatite. No differences in serum calcium or phosphorus or in the ultrastructural characteristics of the thyroid parafollicular cells and the parathyroid parenchymal cells were observed between animals fed the semipurified diet and those fed a commercial chow. The urinary excretion of calcium and magnesium was less and urinary citrate excretion was greater in animals fed the semipurified diet. ImagesFig 1Fig 2Fig 3Fig 4Fig 5Fig 8Fig 9Fig 6Fig 7 PMID:5096368
Cellular control over spicule formation in sea urchin embryos: A structural approach.
Beniash, E; Addadi, L; Weiner, S
1999-03-01
The spicules of the sea urchin embryo form in intracellular membrane-delineated compartments. Each spicule is composed of a single crystal of calcite and amorphous calcium carbonate. The latter transforms with time into calcite by overgrowth of the preexisting crystal. Relationships between the membrane surrounding the spiculogenic compartment and the spicule mineral phase were studied in the transmission electron microscope (TEM) using freeze-fracture. In all the replicas observed the spicules were tightly surrounded by the membrane. Furthermore, a variety of structures that are related to the material exchange process across the membrane were observed. The spiculogenic cells were separated from other cell types of the embryo, frozen, and freeze-dried on the TEM grids. The contents of electron-dense granules in the spiculogenic cells were shown by electron diffraction to be composed of amorphous calcium carbonate. These observations are consistent with the notion that the amorphous calcium carbonate-containing granules contain the precursor mineral phase for spicule formation and that the membrane surrounding the forming spicule is involved both in transport of material and in controlling spicule mineralization. Copyright 1999 Academic Press.
Schulter, Günter; Goessler, Walter; Papousek, Ilona
2012-01-01
Mounting evidence indicates that adult health outcomes such as the development of cardiovascular disease or diabetes can trace some of their roots back to prenatal development. This study investigated the epigenetic impact of a particular prenatal hormonal condition on specific health-related consequences, i.e., on concentrations of minerals and mineral metabolism in adults. In 70 university students, the second-to-fourth digit length (2D:4D) was measured as a proxy of prenatal sex steroid action, and the concentrations of sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca) were determined in hair samples by inductively coupled plasma-mass spectrometry. Mineral concentrations and the mineral ratios Na/K, Na/Mg, and Na/Ca were analyzed in multivariate analyses of variance, with digit ratios and sex of participants as grouping variables. The results were validated in a replication cohort from the general population, and with a wider age-range. In addition, the correlation of mineral concentrations and mineral ratios with blood pressure was examined. Men with relatively lower (i.e., more masculine) and women with relatively higher (i.e., more feminine) digit ratios had higher Na/K, Na/Mg, and Na/Ca ratios than their counterparts. Virtually identical results were obtained in the replication study. Moreover, Na concentrations and Na/K ratios were significantly correlated with systolic blood pressure. The findings suggest that the individual variation in mineral metabolism can be predicted by 2D:4D, indicating that prenatal sex steroid action may be involved in the epigenetic programming of specific metabolic conditions which are highly relevant to adult health and disease. 2011 Wiley Periodicals, Inc.
Liu, Fenwu; Zhou, Jun; Jin, Tongjun; Zhang, Shasha; Liu, Lanlan
2016-01-01
Calcium oxide was added into ferrous ion oxidation system in the presence of Acidithiobacillus ferrooxidans at concentrations of 0-4.00 g/L. The pH, ferrous ion oxidation efficiency, total iron precipitation efficiency, and phase of the solid minerals harvested from different treatments were investigated during the ferrous ion oxidation process. In control check (CK) system, pH of the solution decreased from 2.81 to 2.25 when ferrous ions achieved complete oxidation after 72 h of Acidithiobacillus ferrooxidans incubation without the addition of calcium oxide, and total iron precipitation efficiency reached 20.2%. Efficiency of ferrous ion oxidation and total iron precipitation was significantly improved when the amount of calcium oxide added was ≤1.33 g/L, and the minerals harvested from systems were mainly a mixture of jarosite and schwertmannite. For example, the ferrous ion oxidation efficiency reached 100% at 60 h and total iron precipitation efficiency was increased to 32.1% at 72 h when 1.33 g/L of calcium oxide was added. However, ferrous ion oxidation and total iron precipitation for jarosite and schwertmannite formation were inhibited if the amount of calcium oxide added was above 2.67 g/L, and large amounts of calcium sulfate dihydrate were generated in systems.
Usui, Kenji; Yokota, Shin-Ichiro; Ozaki, Makoto; Sakashita, Shungo; Imai, Takahito; Tomizaki, Kin-Ya
2018-01-01
A core sequence (the 9 C-terminal residues) of calcification-associated peptide (CAP- 1) isolated from the exoskeleton of the red swamp crayfish was previously shown to control calcium carbonate precipitation with chitin. In addition, a modified core sequence in which the phosphorylated serine at the N terminus is replaced with serine exhibits was also previously shown to alter precipitation characteristics with chitin. We focused on calcium carbonate precipitation and attempted to elucidate aspects of the mechanism underlying mineralization. We attempted to evaluate in detail the effects of modifying the N-terminus in the core sequence on calcium carbonate mineralization without chitin. The peptide modifications included phosphorylation, dephosphorylation, and a free or acetylated Nterminus. The peptides were synthesized manually on Wang resin using the DIPCI-DMAP method for the first residue, and Fmoc solid phase peptide synthesis with HBTU-HOBt for the subsequent residues. Prior to calcium carbonate precipitation, calcium carbonate was suspended in MilliQ water. Carbon dioxide gas was bubbled into the stirred suspension, then the remaining solid CaCO3 was removed by filtration. The concentration of calcium ions in the solution was determined by standard titration with ethylenediaminetetraacetate. Calcium carbonate precipitation was conducted in a micro tube for 3 h at 37°C. We used the micro-scale techniques AFM (atomic force microscopy) and TEM (transmission electron microscopy), and the macro-scale techniques chelate titration, HPLC, gel filtration, CD (circular dichroism) and DLS (dynamic light scattering). We determined the morphologies of the calcium carbonate deposits using AFM and TEM. The pS peptide provided the best control of the shape and size of the calcium carbonate round particles. The acetylated peptides (Ac-S and Ac-pS) provided bigger particles with various shapes. S peptide provided a mixture of bigger particles and amorphous particles. We verified these findings using DLS. All the peptide samples produced nanostructures of the expected size in agreement with the AFM and TEM results. We estimated the abilities of these peptides to precipitate calcium carbonate by determining the residual calcium hydrogen carbonate concentration by standard titration with ethylenediaminetetraacetate after calcium carbonate precipitation. The Ac-pS peptide showed the lowest residual calcium hydrogen carbonate concentration whereas the S peptide showed the highest, suggesting that the precipitating activities of these peptides towards calcium carbonate correlated with peptide net charge. Then the gel filtration results showed a large oligomer peak and a small oligomer/monomer peak for all peptide samples in agreement with the AFM, TEM and DLS results. CD measurements showed that all the peptides formed random-coil-like structures. Thus, we used both macro- and micro-observation techniques such as chelate titration, DLS, AFM and TEM to show that the calcium carbonate precipitating activities of four derivatives of the core sequence of CAP-1 may correlate with the peptide net charge. These peptides mainly act as a catalyst rather than as a binder or component of the calcium carbonate deposits (as a template). On the other hand, the morphologies of the calcium carbonate deposits appeared to be dependent on the ability of the peptide to assemble and act as a template. Consequently, elucidating the relationship between peptide sequence and the ability of the peptide to assemble would be indispensable for controlling precipitate morphologies in the near future. This knowledge would provide important clues for elucidating the relationship between peptide sequence and mineralization ability, including deposit morphology and precipitating activity, for use in nanobiochemistry and materials chemistry research. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
The effect of oral ipriflavone on the rat mandible during growth.
Maki, Kenshi; Nishida, Ikuko; Kimura, Mitsutaka
2005-02-01
Different types of ipriflavone (IF) have been reported to be effective when used as a remedy for bone loss due to osteoporosis. However, no information is available regarding the relationship between IF and jaw bone structure. The aim of this study was to examine the effect of IF on rat mandibles during the growth stage. Thirty-two 5-week-old Wistar male rats were divided into four groups. The control group was fed a standard diet, group A received a low calcium diet (calcium content 30 per cent of the standard diet) for 6 weeks, and the other two groups were fed a low calcium diet for 3 weeks and then a standard diet without IF (group B) or with IF (group C) for 3 weeks. In addition, distilled water was provided for all groups. The effects of IF on mandibular size and bone mineral content were investigated, using lateral cephalometric analysis and peripheral quantitative computed tomography (pQCT). For mandibular length, the control group showed a significantly higher value than groups A and B (P < 0.01, P < 0.05, respectively), while group C demonstrated a significantly higher value than group A (P < 0.01). In addition, the control group and group C showed significantly higher values for mandibular ramus height than group A (P < 0.01). However, bone mineral density in trabecular bone was significantly higher in the control group than in the other groups (P < 0.01) and bone mineral density in cortical bone was significantly higher in the control group than groups A, B and C (P < 0.01, P < 0.01, P < 0.05, respectively). Bone mineral density in both trabecular and cortical bone was significantly higher in group C than in groups A and B (P < 0.01, P < 0.05, respectively). These results indicate that complete recovery from calcium deficiency to the level of the control group may not be attainable, even though IF enhances calcium absorption to act on bone cells and promote bone construction. The importance of calcium intake in the early stages of development was confirmed. These findings also suggest an effect of IF on jaw bone structure.
NASA Astrophysics Data System (ADS)
Omelon, S. J.; Stanley, S. Y.; Gorelikov, I.; Matsuura, N.
2011-12-01
The oxygen isotopic composition in bone mineral phosphate is known to reflect the local water composition, environmental humidity, and diet1. Once ingested, biochemical processes presumably equilibrate PO43- with "body water" by the many biochemical reactions involving PO43- 2. Blake et al. demonstrated that enzymatic release of PO43- from organophosphorus compounds, and microbial metabolism of dissolved orthophosphate, significantly exchange the oxygen in precipitated apatite within environmental water3,4, which otherwise does not exchange with water at low temperatures. One of the enzymes that can cleave phosphates from organic substrates is alkaline phosphastase5, the enzyme also associated with bone mineralization. The literature often states that the mineral in bone in hydroxylapatite, however the mineral in bone is carbonated apatite that also contains some fluoride6. Deprotonation of HPO32- occurs at pH 12, which is impossibly high for biological system, and the predominate carbonate species in solution at neutral pH is HCO3-. To produce an apatite mineral without a significant hydroxyl content, it is possible that apatite biomineralization occurs through a polyphosphate pathway, where the oxygen atom required to transform polyphosphate into individual phosphate ions is from carbonate: [PO3-]n + CO32- -> [PO3-]n-1 + PO43- + CO2. Alkaline phosphatase can depolymerise polyphosphate into orthophosphate5. If alkaline phosphatase cleaves an oxygen atom from a calcium-carbonate complex, then there is no requirement for removing a hydrogen atom from the HCO3- or HPO43- ions of body water to form bioapatite. A mix of 1 mL of 1 M calcium polyphosphate hydogel, or nano-particles of calcium polyphosphate, and amorphous calcium carbonate were reacted with alkaline phosphatase, and maintained at neutral to basic pH. After two weeks, carbonated apatite and other calcium phosphate minerals were identified by powder x-ray diffraction. Orthophosphate and unreacted polyphosphate species were detected by Raman and IR spectroscopy. The oxygen isotope data of the reactants and products will also be presented. The possibility that carbonate acts as an intermediate reagent, transferring the oxygen from water to phosphate in biological apatite mineral formation may explain why biological apatite exhibits a significant carbonate content, and how this mineral is formed with an insignificant hydroxyl content. 1 Kohn, M.J., and Cerling, T.E.
NASA Astrophysics Data System (ADS)
Lafhaj, Z.; Filippov, L. O.; Filippova, I. V.
2017-07-01
The flotation separation of salt type calcium minerals is problematic, due to the similarities in their same active Ca2+ related site for interaction with anionic collectors and similar physicochemical characteristics such as solubility, zero-point charge, surface speciation and Ca-site density. The work was performed to achieve effective and selective separation of the calcium-minerals using pure minerals samples: orange calcite with Mg impurities, optic calcite with impurities level and an apatite. The pure samples surface was examined using techniques sensitive near-surface like infrared spectroscopy (FTIR) and chemical composition was obtained by ICPMS. The isoelectric point (IEP) and point of zero charge (PZC) in electrolyte were recorded using electrophoresis method at different ionic strengths of the solution. Mechanisms of charge development at the mineral-water interface are discussed. The time of contact as important parameter for the charge equilibrium was deduced from kinetics study and fixed to 30 minutes. The difference in the values obtained between IEP and PZSE can be explained by the presence of a specific adsorption of cations and anions on the surface. The effect of pure anionic collectors such as oleic and linoleic acid were studied. At low pH, both collectors lead to a good recovery for the calcites. The flotation recovery of optic calcite at pH 9 with sodium oleate is higher than with sodium linoleate. At alkaline pH, apatite showed a better recovery with sodium linoleate.
[Role of physical activity in the prevention of osteoporosis].
Siegrist, Monika
2008-07-01
In recent years, osteoporosis has become a leading cause of morbidity and mortality in elderly women. Research has demonstrated that the prevention of osteoporosis and osteoporosis-related fractures may best be achieved by initiating sound health behaviors early in life and continuing them throughout life. Evidence suggests that osteoporosis is easier to prevent than to treat. In fact, healthy early life practices, including the adequate consumption of most nutrients, calcium in particular, and regular physical activity, contribute to greater bone mineral mass and optimal peak bone mass. Bone is living tissue that responds to exercise by becoming stronger. Two types of exercises are important for building and maintaining bone mass and density: Weight-bearing exercises, in which bones and muscles work against gravity and resistance training that use muscular strength to improve muscle mass and strengthen bone. Exercise can also improve gait, balance, coordination, proprioception, reaction time, and muscle strength, even in very old and frail elderly people. Overall, the evidence strongly suggests that regular physical activity, especially started in childhood and adolescence, is a cheap and safe way of both improving bone strength and reducing the risk to fall.
Mineral resource of the month: Wollastonite
Virta, Robert L.; Van Gosen, Bradley S.
2014-01-01
Wollastonite, a calcium metasilicate, has an ideal composition of 48.3 percent calcium oxide and 51.7 percent silicon dioxide, but it can also contain minor amounts of aluminum, iron, magnesium, manganese, potassium, sodium or strontium substituting for calcium. Wollastonite occurs as prismatic crystals that break into tabular-to-acicular fragments. It is usually white but also may be gray, cream, brown, pale green, or red depending on its impurities and grain size.
Silva-Castro, G. A.; Uad, I.; Gonzalez-Martinez, A.; Rivadeneyra, A.; Gonzalez-Lopez, J.; Rivadeneyra, M. A.
2015-01-01
The precipitation of calcium carbonate and calcium sulphate by isolated bacteria from seawater and real brine obtained in a desalination plant growth in culture media containing seawater and brine as mineral sources has been studied. However, only bioprecipitation was detected when the bacteria were grown in media with added organic matter. Biomineralization process started rapidly, crystal formation taking place in the beginning a few days after inoculation of media; roughly 90% of total cultivated bacteria showed. Six major colonies with carbonate precipitation capacity dominated bacterial community structure cultivated in heterotrophic platable bacteria medium. Taxonomic identification of these six strains through partial 16S rRNA gene sequences showed their affiliation with Gram-positive Bacillus and Virgibacillus genera. These strains were able to form calcium carbonate minerals, which precipitated as calcite and aragonite crystals and showed bacterial fingerprints or bacteria calcification. Also, carbonic anhydrase activity was observed in three of these isolated bacteria. The results of this research suggest that microbiota isolated from sea water and brine is capable of precipitation of carbonate biominerals, which can occur in situ with mediation of organic matter concentrations. Moreover, calcium carbonate precipitation ability of this microbiota could be of importance in bioremediation of CO2 and calcium in certain environments. PMID:26273646
Silva-Castro, G A; Uad, I; Gonzalez-Martinez, A; Rivadeneyra, A; Gonzalez-Lopez, J; Rivadeneyra, M A
2015-01-01
The precipitation of calcium carbonate and calcium sulphate by isolated bacteria from seawater and real brine obtained in a desalination plant growth in culture media containing seawater and brine as mineral sources has been studied. However, only bioprecipitation was detected when the bacteria were grown in media with added organic matter. Biomineralization process started rapidly, crystal formation taking place in the beginning a few days after inoculation of media; roughly 90% of total cultivated bacteria showed. Six major colonies with carbonate precipitation capacity dominated bacterial community structure cultivated in heterotrophic platable bacteria medium. Taxonomic identification of these six strains through partial 16S rRNA gene sequences showed their affiliation with Gram-positive Bacillus and Virgibacillus genera. These strains were able to form calcium carbonate minerals, which precipitated as calcite and aragonite crystals and showed bacterial fingerprints or bacteria calcification. Also, carbonic anhydrase activity was observed in three of these isolated bacteria. The results of this research suggest that microbiota isolated from sea water and brine is capable of precipitation of carbonate biominerals, which can occur in situ with mediation of organic matter concentrations. Moreover, calcium carbonate precipitation ability of this microbiota could be of importance in bioremediation of CO2 and calcium in certain environments.
Treccani, Laura; Mann, Karlheinz; Heinemann, Fabian; Fritz, Monika
2006-01-01
We have isolated a new protein from the nacreous layer of the shell of the sea snail Haliotis laevigata (abalone). Amino acid sequence analysis showed the protein to consist of 134 amino acids and to contain three sequence repeats of ∼40 amino acids which were very similar to the well-known whey acidic protein domains of other proteins. The new protein was therefore named perlwapin. In addition to the major sequence, we identified several minor variants. Atomic force microscopy was used to explore the interaction of perlwapin with calcite crystals. Monomolecular layers of calcite crystals dissolve very slowly in deionized water and recrystallize in supersaturated calcium carbonate solution. When perlwapin was dissolved in the supersaturated calcium carbonate solution, growth of the crystal was inhibited immediately. Perlwapin molecules bound tightly to distinct step edges, preventing the crystal layers from growing. Using lower concentrations of perlwapin in a saturated calcium carbonate solution, we could distinguish native, active perlwapin molecules from denaturated ones. These observations showed that perlwapin can act as a growth inhibitor for calcium carbonate crystals in saturated calcium carbonate solution. The function of perlwapin in nacre growth may be to inhibit the growth of certain crystallographic planes in the mineral phase of the polymer/mineral composite nacre. PMID:16861275
Mineralogy of a mudstone at Yellowknife Bay, Gale crater, Mars.
Vaniman, D T; Bish, D L; Ming, D W; Bristow, T F; Morris, R V; Blake, D F; Chipera, S J; Morrison, S M; Treiman, A H; Rampe, E B; Rice, M; Achilles, C N; Grotzinger, J P; McLennan, S M; Williams, J; Bell, J F; Newsom, H E; Downs, R T; Maurice, S; Sarrazin, P; Yen, A S; Morookian, J M; Farmer, J D; Stack, K; Milliken, R E; Ehlmann, B L; Sumner, D Y; Berger, G; Crisp, J A; Hurowitz, J A; Anderson, R; Des Marais, D J; Stolper, E M; Edgett, K S; Gupta, S; Spanovich, N
2014-01-24
Sedimentary rocks at Yellowknife Bay (Gale crater) on Mars include mudstone sampled by the Curiosity rover. The samples, John Klein and Cumberland, contain detrital basaltic minerals, calcium sulfates, iron oxide or hydroxides, iron sulfides, amorphous material, and trioctahedral smectites. The John Klein smectite has basal spacing of ~10 angstroms, indicating little interlayer hydration. The Cumberland smectite has basal spacing at both ~13.2 and ~10 angstroms. The larger spacing suggests a partially chloritized interlayer or interlayer magnesium or calcium facilitating H2O retention. Basaltic minerals in the mudstone are similar to those in nearby eolian deposits. However, the mudstone has far less Fe-forsterite, possibly lost with formation of smectite plus magnetite. Late Noachian/Early Hesperian or younger age indicates that clay mineral formation on Mars extended beyond Noachian time.
Att, Wael; Kubo, Katsutoshi; Yamada, Masahiro; Maeda, Hatsuhiko; Ogawa, Takahiro
2009-01-01
This study evaluated the biomechanical properties of periosteum-derived mineralized culture on different surface topographies of titanium. Titanium surfaces modified by machining or by acid etching were analyzed using scanning electron microscopy (SEM). Rat mandibular periosteum-derived cells were cultured on either of the titanium surfaces. Cell proliferation was evaluated by cell counts, and gene expression was analyzed using a reverse-transcriptase polymerase chain reaction. Alkaline phosphatase (ALP) stain assay was employed to evaluate osteoblastic activity. Matrix mineralization was examined via von Kossa stain assay, total calcium deposition, and SEM. The hardness and elastic modulus of mineralized cultures were measured using a nano-indenter. The machined surface demonstrated a flat topographic configuration, while the acid-etched surface revealed a uniform micron-scale roughness. Both cell density and ALP activity were significantly higher on the machined surface than on the acid-etched surface. The expression of bone-related genes was up-regulated or enhanced on the acid-etched surface compared to the machined surface. Von Kossa stain showed significantly greater positive areas for the machined surface compared to the acid-etched surface, while total calcium deposition was statistically similar. Mineralized culture on the acid-etched surface was characterized by denser calcium deposition, more mature collagen deposition on the superficial layer, and larger and denser globular matrices inside the matrix than the culture on the machined surface. The mineralized matrix on the acid-etched surface was two times harder than on the machined surface, whereas the elastic modulus was comparable between the two surfaces. The design of this study can be used as a model to evaluate the effect of implant surface topography on the biomechanical properties of periosteum-derived mineralized culture. The results suggest that mandibular periosteal cells respond to different titanium surface topographies differently enough to produce mineralized matrices with different biomechanical qualities.
Polak-Jonkisz, Dorota; Zwolińska, Danuta; Nahaczewska, Wiesława
2010-01-01
Chronic kidney disease (CKD) leads to bone and mineral complications, which are manifested, among others, by hyperparathyroidism, calcium-phosphate and vitamin D balance disturbances. The results of investigation assessing the usefulness of CAP/CIP ratio, (cyclase activating PTH/cyclase inactive PTH) as a marker of bone turnover and bone disturbances in this group of patients are contradictory. was to estimate the concentration of CAP and CIP of parathormone, connection with selected calcium-phosphate balance parameters and usefulness of CAP/CIP ratio to differentiate bone mineral density in patients with CKD treated with repeated haemodialysis. The study included 31 children aged 5 to 18 years. Group I - 15 haemodialysed children. Group II - 16 healthy children. The patients underwent the following serum measurements: calcium concentration (Ca), inorganic phosphate (P), 1.25-dihydroxyvitamin D, parathormone (intact PTH), and CAP, CIP were evaluated with Scantibodies Laboratory Inc test. In group I the densitometric examination was done using the Lunar DPX-L system, performing the overall bone measurement. In children from group I the average values of iPTH concentration and both CIP and CAP components were significantly elevated (p<0.05) as compared to group II. CAP/CIP ratio in group I was <1; in healthy children >1. Average concentrations of Ca and 1.25(OH)2D in serum of group I were lowered, although without statistical significance in comparison with group II. CAP/CIP ratio does not differentiate the children with bone disturbances. Densitometric examination revealed osteopenic changes in 3 children and osteoporosis in 2 children. There were no statistically significant correlations between the examined parameters. 1. The CIP/CAP ratio does not differentiate the bone mineral density status and it is not associated with biochemical parameters of calcium-phosphate metabolism. 2. This indicates its poor diagnostic utility with reference to mineralization disturbances in children with chronic kidney disease.
Bone mineral density in short bowel syndrome: correlation with BMI and serum vitamins C, E and K.
Braga, Camila Bitu Moreno; Bizari, Letícia; Suen, Vivian Miguel Marques; Marchini, Júlio Sérgio; Paula, Francisco José Albuquerque de; Cunha, Selma Freire de Carvalho da
2015-06-01
Bone loss has been established as a major extra-intestinal complication of short bowel syndrome (SBS). The purpose of this study was to correlate bone mineral density (BMD) with body mass index (BMI), serum vitamin and mineral levels in patients with SBS. The study was conducted on 13 patients (8 male and 5 female, 54.7 ± 11.4 years) with SBS (residual small bowel length of 10 to 100 cm). We determined the food ingestion, anthropometry, serum levels of vitamins C, A, D, E and K, as well as serum and urinary levels of phosphorus and calcium. BMD was measured by dual-energy x-ray absorptiometry (DXA). Osteopenia and osteoporosis was diagnosed in all but one SBS patient. Serum levels of vitamin D were low in all volunteers. Sixty-one percent of patients had vitamin E deficiency; hypovitaminosis A and C occurred in one subject. BMI and C, E and K vitamin serum levels correlated with T-score of BMD. Osteopenia and osteoporosis were common in SBS patients. There was a correlation between BMD and the serum levels of vitamins C, E and K, an indicative that such vitamins may influence bone health.
Nakamura, Kazutoshi; Saito, Toshiko; Kobayashi, Ryosaku; Oshiki, Rieko; Kitamura, Kaori; Oyama, Mari; Narisawa, Sachiko; Nashimoto, Mitsue; Takahashi, Shunsuke; Takachi, Ribeka
2012-11-01
Current standard-dose calcium supplements (eg, 1000 mg/d) may increase the risk for cardiovascular events. Effectiveness of lower-dose supplements in preventing bone loss should thus be considered. This study aimed to assess whether calcium supplements of 500 or 250 mg/d effectively prevent bone loss in perimenopausal and postmenopausal Japanese women. We recruited 450 Japanese women between 50 and 75 years of age. They were randomly assigned to receive 500 mg of calcium (as calcium carbonate), 250 mg of calcium, or placebo daily. Medical examinations conducted three times over a 2-year follow-up period assessed bone mineral density (BMD) of the lumbar spine and femoral neck. One-factor repeated measures ANOVA was used for statistical tests. Subgroup analyses were also conducted. Average total daily calcium intake at baseline for the 418 subjects who underwent follow-up examinations was 493 mg/d. Intention-to-treat analysis showed less dramatic decreases in spinal BMD for the 500-mg/d calcium supplement group compared to the placebo group (1.2% difference over 2 years, p = 0.027). Per-protocol analysis (≥80% compliance) revealed that spinal BMD for the 500-mg/d and 250-mg/d calcium supplement groups decreased less than the placebo group (1.6%, p = 0.010 and 1.0%, p = 0.078, respectively), and that femoral neck BMD for the 500-mg/d calcium supplement group decreased less relative to the placebo group (1.0%, p = 0.077). A low-dose calcium supplement of 500 mg/d can effectively slow lumbar spine bone loss in perimenopausal and postmenopausal women with habitually low calcium intake, but its effect on the femoral neck is less certain. Calcium supplementation dosage should thus be reassessed. (Clinical Trials Registry number: UMIN000001176). Copyright © 2012 American Society for Bone and Mineral Research.
Heterogeneous phase reactions of Martian volatiles with putative regolith minerals
NASA Technical Reports Server (NTRS)
Clark, B. C.; Kenley, S. L.; Obrien, D. L.; Huss, G. R.; Mack, R.; Baird, A. K.
1979-01-01
The chemical reactivity of several minerals thought to be present in Martian fines is tested with respect to gases known in the Martian atmosphere. In these experiments, liquid water is excluded from the system, environmental temperatures are maintained below 0 C, and the solar illumination spectrum is stimulated in the visible and UV using a xenon arc lamp. Reactions are detected by mass spectrometric analysis of the gas phase over solid samples. No reactions were detected for Mars nominal gas over sulfates, nitrates, chloride, nontronite clay, or magnetite. Oxidation was not observed for basaltic glass, nontronite, and magnetite. However, experiments incorporating SO2 gas an expected product of volcanism and intrusive volatile release - gave positive results. Displacement of CO2 by SO2 occurred in all four carbonates tested. These reactions are catalyzed by irradiation with the solar simulator. A calcium nitrate hydrate released NO2 in the presence of SO2. These results have implications for the cycling of atmospheric CO2, H2O, and N2 through the regolith.
Fragility and composition of growing rat bone after one week in spaceflight
NASA Technical Reports Server (NTRS)
Patterson-Buckendahl, P.; Arnaud, S. B.; Mechanic, G. L.; Martin, R. B.; Grindeland, R. E.; Cann, C. E.; Mrchanic, G. L. (Principal Investigator)
1987-01-01
To gain some insight into the early effects of spaceflight on skeletal metabolism, we quantified the major chemical constituents and a noncollagenous protein, osteocalcin, in the third-lumbar vertebrae and humeri from 8-wk-old rats that were part of the 7-day NASA Spacelab 3 flight experiments. The ratio of calcium to hydroxyproline in the humeral diaphysis increased from 8.5 in preflight to 9.8 in ground simulation control and only to 8.9 in flight bones. There was no demonstrable change in the fraction of nonmineralized collagen. Osteocalcin content was reduced in the humerus and vertebra. Reduced accumulation of mineral and osteocalcin with no associated decrease in collagen in flight animals suggests that both mineralization and collagen metabolism are impaired in growing animals during spaceflight within a few days after launch. Strength tests of the humeri of flight rats showed substantial deficits that appeared to be related, not only to the reduced bone mass, but also to the composition and quality of new bone formed.
2017-01-01
Summary Flaxseed oil cake was subjected to fermentation with Rhizopus oligosporus (DSM 1964 and ATCC 64063), and the phytate (InsP6) content, myo-inositol phosphate profile and in vitro bioavailability of essential minerals were studied. Flaxseed oil cake had a phytate mass fraction of 13.9 mg/g. A 96-hour fermentation of flaxseed oil cake by R. oligosporus DSM 1964 and R. oligosporus ATCC 64063 decreased the InsP6 content by 48 and 33%, respectively. The strains had different phytate-degrading activities: fermentation of flaxseed oil cake with R. oligosporus DSM 1964 was more advantageous, yielding InsP3-5 as a predominating myo-inositol compound, while fermentation with R. oligosporus ATCC 64603 produced predominantly InsP5-6. Solid-state fermentation of flaxseed oil cake enhanced in vitro bioavailability of calcium by 14, magnesium by 3.3 and phosphorus by 2–4%. PMID:29089855
Chidambaram, Archana; Rodriguez, Douglas; Khan, Saeed; Gower, Laurie
2015-01-01
Randall's plaque (RP) deposits seem to be consistent among the most common type of kidney stone formers, idiopathic calcium oxalate stone formers. This group forms calcium oxalate renal stones without any systemic symptoms, which contributes to the difficulty of understanding and treating this painful and recurring disease. Thus, the development of an in vitro model system to study idiopathic nephrolithiasis, beginning with RP pathogenesis, can help in identifying how plaques and subsequently stones form. One main theory of RP formation is that calcium phosphate deposits initially form in the basement membrane of the thin loops of Henle, which then fuse and spread into the interstitial tissue, and ultimately make their way across the urothelium, where upon exposure to the urine, the mineralized tissue serves as a nidus for overgrowth with calcium oxalate into a stone. Our group has found that many of the unusual morphologies found in RP and stones, such as concentrically laminated spherulites and mineralized collagenous tissue, can be reproduced in vitro using a polymer-induced liquid precursor (PILP) process, in which acidic polypeptides induce a liquid phase amorphous precursor to the mineral, yielding non-equilibrium crystal morphologies. Given that there are many acidic proteins and polysaccharides present in the renal tissue and urine, we have put forth the hypothesis that the PILP system may be involved in urolithiasis. Therefore, our goal is to develop an in vitro model system of these two stages of composite stone formation to study the role that various acidic macromolecules may play. In our initial experiments presented here, the development of "biomimetic" RP was investigated, which will then serve as a nidus for calcium oxalate overgrowth studies. To mimic the tissue environment, MatriStem(®) (ACell, Inc.), a decellularized porcine urinary bladder matrix was used, because it has both an intact epithelial basement membrane surface and a tunica propria layer, thus providing the two types of matrix constituents found associated with mineral in the early stages of RP formation. We found that when using the PILP process to mineralize this tissue matrix, the two sides led to dramatically different mineral textures, and they bore a striking resemblance to native RP, which was not seen in the tissue mineralized via the classical crystal nucleation and growth process. The interstitium side predominantly consisted of collagen-associated mineral, while the luminal side had much less mineral, which appeared to be tiny spherules embedded within the basement membrane. Although these studies are only preliminary, they support our hypothesis that kidney stones may involve non-classical crystallization pathways induced by the large variety of macromolecular species in the urinary environment. We believe that mineralization of native tissue scaffolds is useful for developing a model system of stone formation, with the ultimate goal of developing strategies to avoid RP and its detrimental consequences in stone formation, or developing therapeutic treatments to prevent or cure the disease. Supported by NIDDK grant RO1DK092311.
The salutary effect of dietary calcium on bone mass in a rat model of simulated weightlessness
NASA Technical Reports Server (NTRS)
Bikle, D. D.; Globus, R.; Halloran, B. P.; Morey-Holton, E.
1985-01-01
Whether supplementation of dietary calcium reduces the differences in bone mass of unweighed limbs and normally weighted limbs, and whether parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D (1,25(OH)2D) respond differently to dietary calcium in unweighted animals in comparison with pair-fed controls was studied. The hind limbs of rats were unweighted by a tail suspension method and diets containing 0.1% to 2.4% calcium. After 2 weeks serum calcium, phosphorus, PTH and 1,25(OH)2D intestinal calcium transport were determined and bone mass, ash weight, and calcium in the tibia, L-1 vertebra, and humerus were measured. No significant differences in body weights were observed among the various groups. Suspended rats maintained constant levels of serum calcium and phosphate over the wide range of dietary calcium. Serum PTH and 1,25(OH)2D and intestinal calcium transport fell as dietary calcium was increased. Bone calcium in the tibia and vertebra from suspended rats remained less than that from pair-fed control. It is suggested that although no striking difference between suspended and control animals was observed in response to dieteary calcium, increasing dietary calcium may reduce the negative impact of unloading on the calcium content of the unweighted bones. The salutary effect of high dietary calcium appears to be due to inhibition of bone resorption rather than to stimulation of bone formation.
Marie, Pauline; Labas, Valérie; Brionne, Aurélien; Harichaux, Grégoire; Hennequet-Antier, Christelle; Rodriguez-Navarro, Alejandro B; Nys, Yves; Gautron, Joël
2015-09-01
Chicken eggshell is a biomineral composed of 95% calcite calcium carbonate mineral and of 3.5% organic matrix proteins. The assembly of mineral and its structural organization is controlled by its organic matrix. In a recent study [1], we have used quantitative proteomic, bioinformatic and functional analyses to explore the distribution of 216 eggshell matrix proteins at four key stages of shell mineralization defined as: (1) widespread deposition of amorphous calcium carbonate (ACC), (2) ACC transformation into crystalline calcite aggregates, (3) formation of larger calcite crystal units and (4) rapid growth of calcite as columnar structure with preferential crystal orientation. The current article detailed the quantitative analysis performed at the four stages of shell mineralization to determine the proteins which are the most abundant. Additionally, we reported the enriched GO terms and described the presence of 35 antimicrobial proteins equally distributed at all stages to keep the egg free of bacteria and of 81 proteins, the function of which could not be ascribed.
Marie, Pauline; Labas, Valérie; Brionne, Aurélien; Harichaux, Grégoire; Hennequet-Antier, Christelle; Rodriguez-Navarro, Alejandro B.; Nys, Yves; Gautron, Joël
2015-01-01
Chicken eggshell is a biomineral composed of 95% calcite calcium carbonate mineral and of 3.5% organic matrix proteins. The assembly of mineral and its structural organization is controlled by its organic matrix. In a recent study [1], we have used quantitative proteomic, bioinformatic and functional analyses to explore the distribution of 216 eggshell matrix proteins at four key stages of shell mineralization defined as: (1) widespread deposition of amorphous calcium carbonate (ACC), (2) ACC transformation into crystalline calcite aggregates, (3) formation of larger calcite crystal units and (4) rapid growth of calcite as columnar structure with preferential crystal orientation. The current article detailed the quantitative analysis performed at the four stages of shell mineralization to determine the proteins which are the most abundant. Additionally, we reported the enriched GO terms and described the presence of 35 antimicrobial proteins equally distributed at all stages to keep the egg free of bacteria and of 81 proteins, the function of which could not be ascribed. PMID:26306314
Watson, Timothy F.; Atmeh, Amre R.; Sajini, Shara; Cook, Richard J.; Festy, Frederic
2014-01-01
Objective Since their introduction, calcium silicate cements have primarily found use as endodontic sealers, due to long setting times. While similar in chemistry, recent variations such as constituent proportions, purities and manufacturing processes mandate a critical understanding of service behavior differences of the new coronal restorative material variants. Of particular relevance to minimally invasive philosophies is the potential for ion supply, from initial hydration to mature set in dental cements. They may be capable of supporting repair and remineralization of dentin left after decay and cavity preparation, following the concepts of ion exchange from glass ionomers. Methods This paper reviews the underlying chemistry and interactions of glass ionomer and calcium silicate cements, with dental tissues, concentrating on dentin–restoration interface reactions. We additionally demonstrate a new optical technique, based around high resolution deep tissue, two-photon fluorescence and lifetime imaging, which allows monitoring of undisturbed cement–dentin interface samples behavior over time. Results The local bioactivity of the calcium-silicate based materials has been shown to produce mineralization within the subjacent dentin substrate, extending deep within the tissues. This suggests that the local ion-rich alkaline environment may be more favorable to mineral repair and re-construction, compared with the acidic environs of comparable glass ionomer based materials. Significance The advantages of this potential re-mineralization phenomenon for minimally invasive management of carious dentin are self-evident. There is a clear need to improve the bioactivity of restorative dental materials and these calcium silicate cement systems offer exciting possibilities in realizing this goal. PMID:24113131
CALCIUM CARBONATE DISSOLUTION RATE IN LIMESTONE CONTACTORS
The rate of carbonate mineral dissolution from limestone was studied using a rotating disk apparatus and samples of limestone of varied composition. The purpose of this study was to determine the effect of limestone composition on the kinetics of carbonate mineral dissolution. Th...
21 CFR 172.840 - Polysorbate 80.
Code of Federal Regulations, 2011 CFR
2011-04-01
... emulsifier in ice cream, frozen custard, ice milk, fruit sherbet, and nonstandardized frozen desserts, when... in: (i) Vitamin-mineral preparations containing calcium caseinate in the absence of fat-soluble... daily dose of the preparations. (ii) Fat-soluble vitamins in vitamin and vitamin-mineral preparations...
21 CFR 172.840 - Polysorbate 80.
Code of Federal Regulations, 2010 CFR
2010-04-01
... emulsifier in ice cream, frozen custard, ice milk, fruit sherbet, and nonstandardized frozen desserts, when... in: (i) Vitamin-mineral preparations containing calcium caseinate in the absence of fat-soluble... daily dose of the preparations. (ii) Fat-soluble vitamins in vitamin and vitamin-mineral preparations...
Parkinson, Charles R; Willson, Richard J
2011-01-01
The objective of this study was to evaluate the relative level of dentin tubule occlusion and dentin mineralization conferred by a 5% w/w calcium sodium phosphosilicate (45S5)/1450 ppm fluoride toothpaste in comparison to a range of commercial toothpastes reported to occlude dentin tubules. Two separate experiments were employed to (i) determine the level of dentin tubule occlusion, and (ii) explore the change in dentin mineralization conferred by a number of marketed toothpastes and controls, following twice-daily brushing in a longitudinal, acid challenge-based, dentin disc model. In Study I, 192 bovine dentin discs, polished and etched in citric acid to provide a smooth dentin surface with patent tubules, were divided into eight treatment groups and subjected to brushing with one of seven test toothpastes or deionized water over four days. Prior to and between treatments, the dentin samples were stored in saliva. The test products were fluoridated toothpastes containing: calcium sodium phosphosilicate (45S5); strontium acetate; arginine/calcium carbonate; amine fluoride; calcium sulphate/diphosphate; stannous fluoride; casein stabilized amorphous calcium phosphate toothpaste; and a non-occluding negative control, deionized water. At the end of each treatment day (1 though 4), one group of samples was removed for scanning electron microscopy (SEM) analysis and graded on a categorical visual scale to assess the level of dentin tubule occlusion. A subset of samples from Study I was also cross-sectioned and examined using SEM. For the exploratory mineralization study (Study II), 120 dentin specimens were prepared as previously described and divided into four treatment groups consisting of A, C, F, and a tooth sealant varnish (I), and subjected to the treatment regimen described in Study I. The dentin samples were assessed for changes in surface microhardness using an indenter fitted with a Knoop probe and the level of dentin occlusion. In Study I, the 5% w/w calcium sodium phosphosilicate/1450 ppm fluoride-containing toothpaste (A), the stannous fluoride-containing toothpaste (F), and the strontium acetate-containing toothpaste (B) delivered the highest level of occlusion following four days of twice-daily brushing and a twice-daily acid challenge on days 3 and 4. Surface analysis of a subset of Study I samples, following four days of treatment, indicated that the 5% w/w calcium sodium phosphosilicate/1450 ppm fluoride-containing toothpaste formed a distinct layer at the surface of dentin. For Study II, surface microhardness analysis revealed that the 5% w/w calcium sodium phosphosilicate/1450 ppm fluoride-containing toothpaste (A) delivered significantly more surface hardening then the control or competitor toothpastes on days 2 and 4. Desensitizing toothpastes reported to operate by an occlusion mechanism have been observed to confer varying degrees of dentin tubule occlusion and dentin mineralization over four days in an acid challenge-based in vitro model. A 5% w/w calcium sodium phosphosilicate/1450 ppm fluoride-containing toothpaste was observed to impart a significant level of dentin tubule occlusion and surface hardening, and form durable occlusive deposits following four days of twice-daily brushing in vitro.
Misbah, Mohamed Hamed; Santos, Mercedes; Quintanilla, Luis; Günter, Christina; Alonso, Matilde; Taubert, Andreas
2017-01-01
Understanding the mechanisms responsible for generating different phases and morphologies of calcium phosphate by elastin-like recombinamers is supreme for bioengineering of advanced multifunctional materials. The generation of such multifunctional hybrid materials depends on the properties of their counterparts and the way in which they are assembled. The success of this assembly depends on the different approaches used, such as recombinant DNA technology and click chemistry. In the present work, an elastin-like recombinamer bearing lysine amino acids distributed along the recombinamer chain has been cross-linked via Huisgen [2 + 3] cycloaddition. The recombinamer contains the SNA15 peptide domains inspired by salivary statherin, a peptide epitope known to specifically bind to and nucleate calcium phosphate. The benefit of using click chemistry is that the hybrid elastin-like-statherin recombinamers cross-link without losing their fibrillar structure. Mineralization of the resulting hybrid elastin-like-statherin recombinamer hydrogels with calcium phosphate is described. Thus, two different hydroxyapatite morphologies (cauliflower- and plate-like) have been formed. Overall, this study shows that crosslinking elastin-like recombinamers leads to interesting matrix materials for the generation of calcium phosphate composites with potential applications as biomaterials. PMID:28487820
Ultrasonically assisted extraction of calcium and ash from char
NASA Astrophysics Data System (ADS)
Mathumba, E. E.; Mbaya, R. K. K.; Kolesnikov, A.
2018-03-01
This study characterized and removed calcium and ash content from char to improve the chemical quality of char as reductant for titanium smelting application. Calcium in char can be classified in two parts: mineral matter and cationic metals associated with organic matrix. Virgin and chemically treated char was characterized by using ISO 1171, wet chemistry methods, ISO 19579, XRF, and B.E.T. methods. In this present work, demineralization of char with mild chemical leachants such as acetic acid, citric acid, gluconic acid and Ethylene Diamine Tetra Acetic acid with three different ultrasonic power input (150 W, 270 W and 300 W) and semi-dual frequency of 40 kHz tank was investigated. Actual power dissipated into the system was calculated from the calorimetric measurement. An optimum set of process parameters are identified and validated. The ultrasound technology was compared with soaking technology to determine the efficiency of ultrasound system for the removal of calcium. The removal of calcium was exponentially higher with ultrasonic treatment than without it. Results revealed that mild chemical reagents do not harm the carbon content of char. It is evident from the results that amongst the leachants used; acetic and citric acid has caused significant removal of mineral phases.
Palandri, J.L.; Reed, M.H.
2004-01-01
In a series of water-rock reaction simulations, we assess the processes of serpentinization of harzburgite and related calcium metasomatism resulting in rodingite-type alteration, and seafloor carbonate chimney precipitation. At temperatures from 25 to 300??C (P = 10 to 100 bar), using either fresh water or seawater, serpentinization simulations produce an assemblage commonly observed in natural systems, dominated by serpentine, magnetite, and brucite. The reacted waters in the simulations show similar trends in composition with decreasing water-rock ratios, becoming hyper-alkaline and strongly reducing, with increased dissolved calcium. At 25??C and w/r less than ???32, conditions are sufficiently reducing to yield H2 gas, nickel-iron alloy and native copper. Hyperalkalinity results from OH- production by olivine and pyroxene dissolution in the absence of counterbalancing OH- consumption by alteration mineral precipitation except at very high pH; at moderate pH there are no stable calcium minerals and only a small amount of chlorite forms, limited by aluminum, thus allowing Mg2+ and Ca2+ to accumulate in the aqueous phase in exchange for H+. The reducing conditions result from oxidation of ferrous iron in olivine and pyroxene to ferric iron in magnetite. Trace metals are computed to be nearly insoluble below 300??C, except for mercury, for which high pH stabilizes aqueous and gaseous Hg??. In serpentinization by seawater at 300??C, Ag, Au, Pd, and Pt may approach ore-forming concentrations in sulfide complexes. Simulated mixing of the fluid derived from serpentinization with cold seawater produces a mineral assemblage dominated by calcite, similar to recently discovered submarine, ultramafic rock-hosted, carbonate mineral deposits precipitating at hydrothermal vents. Simulated reaction of gabbroic or basaltic rocks with the hyperalkaline calcium- and aluminum-rich fluid produced during serpentinization at 300??C yields rodingite-type mineral assemblages, including grossular, clinozoisite, vesuvianite, prehnite, chlorite, and diopside. ?? 2004 Elsevier Ltd.
Peak bone strength is influenced by calcium intake in growing rats.
Viguet-Carrin, S; Hoppler, M; Membrez Scalfo, F; Vuichoud, J; Vigo, M; Offord, E A; Ammann, P
2014-11-01
In this study we investigated the effect of supplementing the diet of the growing male rat with different levels of calcium (from low to higher than recommended intakes at constant Ca/P ratio), on multiple factors (bone mass, strength, size, geometry, material properties, turnover) influencing bone strength during the bone accrual period. Rats, age 28days were supplemented for 4weeks with high Ca (1.2%), adequate Ca (0.5%) or low Ca level (0.2%). Bone metabolism and structural parameters were measured. No changes in body weight or food intake were observed among the groups. As anticipated, compared to the adequate Ca intake, low-Ca intake had a detrimental impact on bone growth (33.63 vs. 33.68mm), bone strength (-19.7% for failure load), bone architecture (-58% for BV/TV) and peak bone mass accrual (-29% for BMD) due to the hormonal disruption implied in Ca metabolism. In contrast, novel, surprising results were observed in that higher than adequate Ca intake resulted in improved peak bone strength (106 vs. 184N/mm for the stiffness and 61 vs. 89N for the failure load) and bone material properties (467 vs. 514mPa for tissue hardness) but these effects were not accompanied by changes in bone mass, size, microarchitecture or bone turnover. Hormonal factors, IGF-I and bone modeling were also evaluated. Compared to the adequate level of Ca, IGF-I level was significantly lower in the low-Ca intake group and significantly higher in the high-Ca intake group. No detrimental effects of high Ca were observed on bone modeling (assessed by histomorphometry and bone markers), at least in this short-term intervention. In conclusion, the decrease in failure load in the low calcium group can be explained by the change in bone geometry and bone mass parameters. Thus, improvements in mechanical properties can be explained by the improved quality of intrinsic bone tissue as shown by nanoindentation. These results suggest that supplemental Ca may be beneficial for the attainment of peak bone strength and that multiple factors linked to bone mass and strength should be taken into account when setting dietary levels of adequate mineral intake to support optimal peak bone mass acquisition. Copyright © 2014 Elsevier Inc. All rights reserved.
Ziegler, Andreas
2008-01-01
Before moulting, terrestrial isopods resorb calcium carbonate (CaCO(3)) from the posterior cuticle and store it in sternal deposits. These consist mainly of amorphous calcium carbonate (ACC) spherules that develop within the ecdysial space between the anterior sternal epithelium and the old cuticle. Ions that occur in the moulting fluid, including those required for mineral deposition, are transported from the hemolymph into the ecdysial space by the anterior sternal epithelial cells. The cationic composition of the moulting fluid probably affects mineral deposition and may provide information on the ion-transport activity of the sternal epithelial cells. This study presents the concentrations of inorganic cations within the moulting fluid of the anterior sternites during the late premoult and intramoult stages. The most abundant cation is Na(+) followed by Mg(2+), Ca(2+) and K(+). The concentrations of these ions do not change significantly between the stages whereas the mean pH changed from 8.2 to 6.9 units between mineral deposition in late premoult, and resorption in intramoult, respectively. Measurements of the transepithelial potential show that there is little driving force for passive movements of calcium across the anterior sternal epithelium. The results suggest a possible role of magnesium ions in ACC formation, and a contribution of pH changes to CaCO(3) precipitation and dissolution.
NASA Astrophysics Data System (ADS)
Chang, Joshua C.; Miura, Robert M.
2016-04-01
In vertebrates, insufficient availability of calcium and inorganic phosphate ions in extracellular fluids leads to loss of bone density and neuronal hyper-excitability. To counteract this problem, calcium ions are usually present at high concentrations throughout bodily fluids—at concentrations exceeding the saturation point. This condition leads to the opposite situation where unwanted mineral sedimentation may occur. Remarkably, ectopic or out-of-place sedimentation into soft tissues is rare, in spite of the thermodynamic driving factors. This fortunate fact is due to the presence of auto-regulatory proteins that are found in abundance in bodily fluids. Yet, many important inflammatory disorders such as atherosclerosis and osteoarthritis are associated with this undesired calcification. Hence, it is important to gain an understanding of the regulatory process and the conditions under which it can go awry. In this manuscript, we extend mean-field continuum classical nucleation theory of the growth of clusters to encompass surface shielding. We use this formulation to study the regulation of sedimentation of calcium phosphate salts in biological tissues through the mechanism of post-nuclear shielding of nascent mineral particles by binding proteins. We develop a mathematical description of this phenomenon using a countable system of hyperbolic partial differential equations. A critical concentration of regulatory protein is identified as a function of the physical parameters that describe the system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, Joshua C., E-mail: joshchang@ucla.edu; Miura, Robert M., E-mail: miura@njit.edu
In vertebrates, insufficient availability of calcium and inorganic phosphate ions in extracellular fluids leads to loss of bone density and neuronal hyper-excitability. To counteract this problem, calcium ions are usually present at high concentrations throughout bodily fluids—at concentrations exceeding the saturation point. This condition leads to the opposite situation where unwanted mineral sedimentation may occur. Remarkably, ectopic or out-of-place sedimentation into soft tissues is rare, in spite of the thermodynamic driving factors. This fortunate fact is due to the presence of auto-regulatory proteins that are found in abundance in bodily fluids. Yet, many important inflammatory disorders such as atherosclerosis andmore » osteoarthritis are associated with this undesired calcification. Hence, it is important to gain an understanding of the regulatory process and the conditions under which it can go awry. In this manuscript, we extend mean-field continuum classical nucleation theory of the growth of clusters to encompass surface shielding. We use this formulation to study the regulation of sedimentation of calcium phosphate salts in biological tissues through the mechanism of post-nuclear shielding of nascent mineral particles by binding proteins. We develop a mathematical description of this phenomenon using a countable system of hyperbolic partial differential equations. A critical concentration of regulatory protein is identified as a function of the physical parameters that describe the system.« less
NASA Astrophysics Data System (ADS)
Oestreicher, Z.; Lower, B.; Lower, S.; Bazylinski, D. A.
2011-12-01
Biomineralization occurs throughout the living world; a few common examples include iron oxide in chiton teeth, calcium carbonate in mollusk shells, calcium phosphate in animal bones and teeth, silica in diatom shells, and magnetite crystals inside the cells of magnetotactic bacteria. Biologically controlled mineralization is characterized by biominerals that have species-specific properties such as: preferential crystallographic orientation, consistent particle size, highly ordered spatial locations, and well-defined composition and structure. It is well known that magnetotactic bacteria synthesize crystals of magnetite inside of their cells, but how they mineralize the magnetite is poorly understood. Magnetosomes have a species-specific morphology that is due to specific proteins involved in the mineralization process. In addition to magnetite crystals, magnetotactic bacteria also produce inclusion bodies or granules that contain different elements, such as phosphorus, calcium, and sulfur. In this study we used the transmission electron microscope to analyze the structure of magnetite crystals and inclusion bodies from different species of magnetotactic bacteria in order to determine the composition of the inclusion bodies and to ascertain whether or not the magnetite crystals contain elements other than iron and oxygen. Using energy dispersive spectroscopy we found that different bacteria from different environments possess inclusion bodies that contain different elements such as phosphorus, calcium, barium, magnesium, and sulfur. These differences may reflect the conditions of the environment in which the bacteria inhabit.
Scholz-Ahrens, Katharina E; Ade, Peter; Marten, Berit; Weber, Petra; Timm, Wolfram; Açil, Yahya; Glüer, Claus-C; Schrezenmeir, Jürgen
2007-03-01
Several studies in animals and humans have shown positive effects of nondigestible oligosaccharides (NDO) on mineral absorption and metabolism and bone composition and architecture. These include inulin, oligofructose, fructooligosaccharides, galactooligosaccharides, soybean oligosaccharide, and also resistant starches, sugar alcohols, and difructose anhydride. A positive outcome of dietary prebiotics is promoted by a high dietary calcium content up to a threshold level and an optimum amount and composition of supplemented prebiotics. There might be an optimum composition of fructooligosaccharides with different chain lengths (synergy products). The efficacy of dietary prebiotics depends on chronological age, physiological age, menopausal status, and calcium absorption capacity. There is evidence for an independent probiotic effect on facilitating mineral absorption. Synbiotics, i.e., a combination of probiotics and prebiotics, can induce additional effects. Whether a low content of habitual NDO would augment the effect of dietary prebiotics or synbiotics remains to be studied. The underlying mechanisms are manifold: increased solubility of minerals because of increased bacterial production of short-chain fatty acids, which is promoted by the greater supply of substrate; an enlargement of the absorption surface by promoting proliferation of enterocytes mediated by bacterial fermentation products, predominantly lactate and butyrate; increased expression of calcium-binding proteins; improvement of gut health; degradation of mineral complexing phytic acid; release of bone-modulating factors such as phytoestrogens from foods; stabilization of the intestinal flora and ecology, also in the presence of antibiotics; stabilization of the intestinal mucus; and impact of modulating growth factors such as polyamines. In conclusion, prebiotics are the most promising but also best investigated substances with respect to a bone-health-promoting potential, compared with probiotics and synbiotics. The results are more prominent in animal models, where more studies have been performed, than in human studies, where experimental conditions are more difficult to control.
Lactose intolerance in prostate cancer patients: incidence and associated factors.
Agarwal, Mayank Mohan; Rana, Satyavati V; Mandal, Arup Kumar; Malhotra, Sunita; Khandelwal, Niranjan; Kumar, Santosh; Acharya, Naveen Chandra; Singh, Shrawan Kumar
2008-03-01
Osteoporosis is common in prostate cancer (CaP) patients both before and after institution of androgen deprivation therapy and is associated with significant morbidity. Lactose intolerance (LI) can affect bone mass but has not been studied in this group of patients. The objective of this study was to compare the incidence of LI in CaP patients with that in the general population and to identify factors affecting lactose intolerance in CaP patients. Fifty-five men with CaP planned for bilateral orchidectomy were enrolled in the study and their baseline characteristics including age, weight, height, body mass index (BMI), prostate-specific antigen, serum calcium profile, lactose tolerance status, physical activity, alcohol intake and smoking, bone mineral density and calcium intake were registered. The data on lactose tolerance in these patients were compared with those of 81 age-matched controls (data taken from the available database). The incidence of LI in CaP patients was significantly less than that in the control group (36.2% and 58.3%, respectively, p = 0.027). A significantly greater number of CaP patients in the lactose-tolerant group had a calcium intake of >1500 mg/day (p = 0.03) and that of milk >500 ml/day (p = 0.05) than those in the intolerant group. Age >70 years, BMI <25 kg/m2, height >163 cm, lower physical activity and co-abuse of alcohol and smoking significantly correlated with the presence of LI (p < or = 0.05). Patients with serum calcium <9 mg/dl had higher fasting breath H2 levels and a higher proportion had a BMI >25 kg/m2 and weight >65 kg. The incidence of LI in CaP patients is less than that in the general population despite a higher incidence of osteoporosis, indicating a complex etiology of CaP-related osteoporosis. Certain physical characteristics and personal habits are important in determining lactose-tolerant status.
Young, David; Young, John D.
2009-01-01
Serum-derived granulations and purported nanobacteria (NB) are pleomorphic apatite structures shown to resemble calcium granules widely distributed in nature. They appear to be assembled through a dual inhibitory-seeding mechanism involving proteinaceous factors, as determined by protease (trypsin and chymotrypsin) and heat inactivation studies. When inoculated into cell culture medium, the purified proteins fetuin-A and albumin fail to induce mineralization, but they will readily combine with exogenously added calcium and phosphate, even in submillimolar amounts, to form complexes that will undergo morphological transitions from nanoparticles to spindles, films, and aggregates. As a mineralization inhibitor, fetuin-A is much more potent than albumin, and it will only seed particles at higher mineral-to-protein concentrations. Both proteins display a bell-shaped, dose-dependent relationship, indicative of the same dual inhibitory-seeding mechanism seen with whole serum. As ascertained by both seeding experiments and gel electrophoresis, fetuin-A is not only more dominant but it appears to compete avidly for nanoparticle binding at the expense of albumin. The nanoparticles formed in the presence of fetuin-A are smaller than their albumin counterparts, and they have a greater tendency to display a multi-layered ring morphology. In comparison, the particles seeded by albumin appear mostly incomplete, with single walls. Chemically, spectroscopically, and morphologically, the protein-mineral particles resemble closely serum granules and NB. These particles are thus seen to undergo an amorphous to crystalline transformation, the kinetics and completeness of which depend on the protein-to-mineral ratios, with low ratios favoring faster conversion to crystals. Our results point to a dual inhibitory-seeding, de-repression model for the assembly of particles in supersaturated solutions like serum. The presence of proteins and other inhibitory factors tend to block apatite nuclei formation or to stabilize the nascent nuclei as amorphous or semi-crystalline spherical nanoparticles, until the same inhibitory influences are overwhelmed or de-repressed, whereby the apatite nuclei grow in size to coalesce into crystalline spindles and films—a mechanism that may explain not only the formation of calcium granules in nature but also normal or ectopic calcification in the body. PMID:19956594
Structural and chemical insect defenses in calcium oxalate defective mutants of Medicago truncatula
USDA-ARS?s Scientific Manuscript database
Plant structures can act as defense against herbivorous insects, causing them to avoid feeding on a given plant or tissue. Mineral crystals of calcium oxalate in leaves of Medicago truncatula Gaertn. are effective deterrents of lepidopteran feeding, and they inhibit conversion of leaves into insect ...
Genomics of mineral nutrient biofortification: calcium, iron and zinc
USDA-ARS?s Scientific Manuscript database
Dietary deficiencies affect nearly half of the people on the planet, who simply do not receive sufficient nutrition from the food they buy or grow. Inadequate calcium, iron, and zinc consumption create short and long term health problems, which in turn can magnify and stagnate national development. ...
Application of fundamental principles to mineral scale reduction : case studies
Peter W. Hart; Alan W. Rudie
2005-01-01
This paper will present several successful case studies where scale has been eliminated in mills including calcium carbonate scale in a white liquor strainer, calcium oxalate scale in the D0 stage, enzymatic treatment of brown stock to eliminate oxalate scale, and control of barium sulfate scale.
Coarse particle speciation at selected locations in the rural continental United States
NASA Astrophysics Data System (ADS)
Malm, William C.; Pitchford, Marc L.; McDade, Charles; Ashbaugh, Lowell L.
A few short-term special studies at National Parks have shown that coarse mass (CM) (2.5- 10μm) may not be just crustal minerals but may consist of a substantial amount ( ≈40-50%) of carbonaceous material and inorganic salts such as calcium nitrate and sodium nitrate. To more fully investigate the composition of coarse particles, a program of coarse particle sampling and speciation analysis at nine of the Interagency Monitoring of Protected Visual Environments (IMPROVE) sites was initiated 19 March 2003 and operated through the year 2004. Only the data for 2004 are reported here. Sites were selected to be representative of the continental United States and were operated according to IMPROVE protocol analytical procedures. Crustal minerals (soil) are the single largest contributor to CM at all but one monitoring location. The average fractional contributions range from a high of 76% at Grand Canyon National Park to a low of 34% at Mount Rainier National Park. The second largest contributor to CM is organic mass, which on an average annual fractional basis is highest at Mount Rainier at 59%. At Great Smoky Mountains National Park, organic mass contributes 40% on average, while at four sites organic mass concentrations contribute between 20% and 30% of the CM. Nitrates are on average the third largest contributor to CM concentrations. The highest fractional contributions of nitrates to CM are at Brigantine National Wildlife Refuge, Great Smoky Mountains, and San Gorgonio wilderness area at 10-12%. Sulfates contribute less than about 5% at all sites.
Frisoli, Alberto; Chaves, Paulo H M; Pinheiro, Marcelo Medeiros; Szejnfeld, Vera Lucia
2005-05-01
In a randomized, double-blind, placebo-controlled clinical trial, we evaluated the effect of a 2-year treatment with nandrolone decanoate (ND) on bone mineral density (BMD) of lumbar spine, femoral neck, and trochanter and on vertebral fracture rate, muscle mass, and hemoglobin levels. Sixty-five osteoporotic women older than 70 years were studied. Thirty-two patients received injections of 50 mg ND, and 33 received placebos every 3 weeks. All patients received 500 mg calcium tablets daily. Compared to baseline, ND increased the BMD of the lumbar spine (3.4% +/- 6.0 and 3.7% +/- 7.4; p < .05) and femoral neck (4.1% +/- 7.3 and 4.7% +/- 8.0; p < .05) after 1 and 2 years, respectively. The BMD of trochanter increased significantly only after the first year (4.8% +/- 9.3, p < .05). Compared to the placebo group, the ND group presented with significantly increased BMD of the trochanter and neck. ND significantly reduced incidence of new vertebral fractures (21% vs 43% in the placebo group; p < .05). ND showed a significant statistical increase in lean body mass after the first (6.2% +/- 5.8; p < .01) and second years (11.9% +/- 29.2; p < .01). In addition, a 2-year treatment with ND significantly increased hemoglobin levels compared to baseline (14.3%; p < .01) and placebo (p < .01). ND increased BMD, hemoglobin levels, and muscle mass, and reduced the vertebral fracture rate of elderly osteoporotic women.
Favorable effect of moderate dose caffeine on the skeletal system in ovariectomized rats.
Folwarczna, Joanna; Pytlik, Maria; Zych, Maria; Cegieła, Urszula; Kaczmarczyk-Sedlak, Ilona; Nowińska, Barbara; Sliwiński, Leszek
2013-10-01
Caffeine, a methylxanthine present in coffee, has been postulated to be responsible for an increased risk of osteoporosis in coffee drinkers; however, the data are inconsistent. The aim of the present study was to investigate the effects of a moderate dose of caffeine on the skeletal system of rats with normal and decreased estrogen level (developing osteoporosis due to estrogen deficiency). The experiments were carried out on mature nonovariectomized and ovariectomized Wistar rats, divided into control rats and rats receiving caffeine once daily, 20 mg/kg p.o., for 4 wk. Serum bone turnover markers, bone mass, mass of bone mineral, calcium and phosphorus content, histomorphometric parameters, and bone mechanical properties were examined. Caffeine favorably affected the skeletal system of ovariectomized rats, slightly inhibiting the development of bone changes induced by estrogen deficiency (increasing bone mineralization, and improving the strength and structure of cancellous bone). Moreover, it favorably affected mechanical properties of compact bone. There were no significant effects of caffeine in rats with normal estrogen levels. In conclusion, results of the present study indicate that low-to-moderate caffeine intake may exert some beneficial effects on the skeletal system of mature organisms. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
A two-year program of aerobics and weight training enhances bone mineral density of young women.
Friedlander, A L; Genant, H K; Sadowsky, S; Byl, N N; Glüer, C C
1995-04-01
Previous research suggests that physical activity may have a beneficial effect on bone mineral density (BMD) in women. This relationship was explored in a 2-year, randomized, intervention trial investigating the efficacy of exercise and calcium supplementation on increasing peak bone mass in young women. One hundred and twenty-seven subjects (ages of 20-35 years) were randomly assigned either to an exercise program that contained both aerobics and weight training components or to a stretching program. Calcium supplementation (up to 1500 mg/day including dietary intake) or placebo was given in a double-blinded design to all subjects. Spinal trabecular BMD was determined using quantitative computed tomography (QCT). Spinal integral, femoral neck, and trochanteric BMD were measured by dual X-ray absorptiometry (DXA) and calcaneal BMD by single photon absorptiometry (SPA). Fitness variables included maximal aerobic capacity (VO2max), and isokinetic muscle performance of the trunk and thigh. Measurements were made at baseline, 1 year, and 2 years. Sixty-three subjects (32 exercise, 31 stretching) completed the study, and all the measured bone parameters indicated a positive influence of the exercise intervention. There were significant positive differences in BMD between the exercise and stretching groups for spinal trabecular (2.5%), femoral neck (2.4%), femoral trochanteric (2.3%), and calcaneal (6.4%) measurements. The exercise group demonstrated a significant gain in BMD for spinal integral (1.3 +/- 2.8%, p < 0.02), femoral trochanteric (2.6 +/- 6.1%, p < 0.05), and calcaneal (5.6 +/- 5.1, p < 0.01) measurements. In contrast to exercise, the calcium intervention had no positive effect on any of the bone parameters. In regard to fitness parameters, the exercise group completed the study with significant gains in VO2max and isokinetic (peak torque) values for the knee flexion and extension and trunk extension. This study indicates that over a 2-year period, a combined regimen of aerobics and weight training has beneficial effects on BMD and fitness parameters in young women. However, the addition of daily calcium supplementation does not add significant benefit to the intervention.
A two-year program of aerobics and weight training enhances bone mineral density of young women
NASA Technical Reports Server (NTRS)
Friedlander, A. L.; Genant, H. K.; Sadowsky, S.; Byl, N. N.; Gluer, C. C.
1995-01-01
Previous research suggests that physical activity may have a beneficial effect on bone mineral density (BMD) in women. This relationship was explored in a 2-year, randomized, intervention trial investigating the efficacy of exercise and calcium supplementation on increasing peak bone mass in young women. One hundred and twenty-seven subjects (ages of 20-35 years) were randomly assigned either to an exercise program that contained both aerobics and weight training components or to a stretching program. Calcium supplementation (up to 1500 mg/day including dietary intake) or placebo was given in a double-blinded design to all subjects. Spinal trabecular BMD was determined using quantitative computed tomography (QCT). Spinal integral, femoral neck, and trochanteric BMD were measured by dual X-ray absorptiometry (DXA) and calcaneal BMD by single photon absorptiometry (SPA). Fitness variables included maximal aerobic capacity (VO2max), and isokinetic muscle performance of the trunk and thigh. Measurements were made at baseline, 1 year, and 2 years. Sixty-three subjects (32 exercise, 31 stretching) completed the study, and all the measured bone parameters indicated a positive influence of the exercise intervention. There were significant positive differences in BMD between the exercise and stretching groups for spinal trabecular (2.5%), femoral neck (2.4%), femoral trochanteric (2.3%), and calcaneal (6.4%) measurements. The exercise group demonstrated a significant gain in BMD for spinal integral (1.3 +/- 2.8%, p < 0.02), femoral trochanteric (2.6 +/- 6.1%, p < 0.05), and calcaneal (5.6 +/- 5.1, p < 0.01) measurements. In contrast to exercise, the calcium intervention had no positive effect on any of the bone parameters. In regard to fitness parameters, the exercise group completed the study with significant gains in VO2max and isokinetic (peak torque) values for the knee flexion and extension and trunk extension. This study indicates that over a 2-year period, a combined regimen of aerobics and weight training has beneficial effects on BMD and fitness parameters in young women. However, the addition of daily calcium supplementation does not add significant benefit to the intervention.
Microgreens of brassicaceae: mineral composition and content of 30 varieties
USDA-ARS?s Scientific Manuscript database
The aim of the present study was to analyze the mineral content and concentration of 30 species of microgreens, representative 10 genera of the Brassicaceae family. Brassicaceae microgreens were assayed for concentrations of macroelements, including calcium (Ca), magnesium (Mg), phosphorous (P), sod...
Barr, S I; Petit, M A; Vigna, Y M; Prior, J C
2001-05-01
This 2-year prospective study examined associations among bone mineral acquisition and physical, maturational, and lifestyle variables during the pubertal transition in healthy girls. Forty-five girls, initially 10.5+/-0.6 years, participated. Body composition and bone mineral content (BMC) at the spine and total body (TB) were assessed at baseline and annually thereafter using dual-energy X-ray absorptiometry (DXA). Nutrient intakes were assessed using 3-day diet records and a calcium food frequency questionnaire (FFQ), physical activity by questionnaire, sexual maturation using Tanner's stages of breast and pubic hair maturation, growth by height and weight, and eating attitudes using the children's Eating Attitudes Test (Children's EAT). Mean children's EAT subscale scores (dieting, oral control [OC], and bulimia) were stable over time. Median split of OC subscale scores was used to form high and low OC groups. Groups had similar body composition, dietary intake, activity, and Tanner stage at baseline and 2 years. Using height, weight, and Tanner breast stage as covariates, girls with low OC scores had greater TB BMC at baseline (1452+/-221 g vs. 1387+/-197 g; p = 0.030) and 2 years (2003+/-323 g vs. 1909+/-299 g; p = 0.049) and greater lumbar spine (LS) BMC at 2 years (45.2+/-8.8 g vs. 41.2+/-9.6 g; p = 0.042). In multiple regression analysis, OC score predicted baseline, 2 years, and 2-year change in TB and spinal BMC, contributing 0.9-7.6% to explained variance. Calcium intake predicted baseline, 2 years, and 2-year change in TB BMC, explaining 1.6-5.3% of variance. We conclude that both OC and habitual calcium intake may influence bone mineral acquisition.
Xu, Xuebin; Hu, Xin; Ding, Zhuhong; Chen, Yijun
2017-12-01
The potential release of toxic elements and the stability of carbon in sludge-based biochars are important on their application in soil remediation and wastewater treatment. In this study, municipal sludge was co-pyrolyzed with calcium carbonate (CaCO 3 ) and calcium dihydrogen phosphate [Ca(H 2 PO 4 ) 2 ] under 300 and 600 °C, respectively. The basic physicochemical properties of the resultant biochars were characterized and laboratory chemical oxidation and leaching experiments of toxic elements were conducted to evaluate the chemical stability of carbon in biochars and the potential release of toxic elements from biochars. Results show that the exogenous minerals changed the physico-chemical properties of the resultant biochars greatly. Biochars with exogenous minerals, especially Ca(H 2 PO 4 ) 2 , decreased the release of Zn, Cr, Ni, Cu, Pb, and As and the release ratios were less than 1%. Tessier's sequential extraction analysis revealed that labile toxic elements were transferred to residual fraction in the biochars with high pyrolysis temperature (600 °C) and exogenous minerals. Low risks for biochar-bound Pb, Zn, Cd, As, Cr, and Cu were confirmed according to risk assessment code (RAC) while the potential ecological risk index (PERI) revealed that the exogenous Ca(H 2 PO 4 ) 2 significantly decreased the risks from considerable to moderate level. Moreover, the exogenous minerals significantly increased the chemical stability of carbon in 600 °C-pyrolyzed biochars by 10-20%. These results indicated that the copyrolysis of sludge with phosphate and carbonate, especially phosphate, were effective methods to prepare the sludge-based biochars with immobilized toxic elements and enhanced chemical stability of carbon. Copyright © 2017 Elsevier Ltd. All rights reserved.
Aljarallah, Badr; Fernandes, Gail; Jeejeebhoy, Khursheed N; Gramlich, Leah M; Whittaker, J S; Armstrong, David; Duerksen, Don R; Allard, Johane P
2012-07-01
Vitamin K supplementation improves bone health, and its absence might be associated with low bone mineral density (BMD). The authors aim to assess vitamin K supplementation practices in Canadian home parenteral nutrition (HPN) programs and their relationship with BMD. This is a cross-sectional study of 189 patients from the Canadian HPN registry. All 189 patients studied received M.V.I.-12, which does not contain vitamin K. Of those, 41.3% were supplemented with 10 mg of intravenous vitamin K (VK+) weekly, whereas the others did not receive vitamin K except via lipid emulsion (VK-). Short bowel syndrome accounted for 69% of VK+ and 46% of VK- patients. On univariate analysis, VK+ patients had substantially lower body mass index (BMI) and received lower bisphosphonate infusion than did VK-patients. There were no statistically significant differences in HPN calcium or lipid content, liver function test results, age, sex, or reason for HPN between the 2 groups. Patients who were VK+ had higher lumbar spine T scores and hip T scores than did VK-patients. General linear modeling analysis, adjusted for BMI, age, PN magnesium, PN phosphate, PN calcium, and bisphosphonate as possible predictors of BMD, showed a trend toward better hip T scores (P = .063) for VK+ patients compared with VK- patients. In HPN patients supplemented with vitamin K, the trend toward a better hip BMD compared with no supplementation suggests a role for vitamin K in preserving BMD. This requires further study.
Oso, A O; Idowu, A A; Niameh, O T
2011-08-01
Growth response, nutrient and mineral retention, bone mineral content and walking ability of broiler chicken fed dietary inclusion of various unconventional calcium sources were studied using 160-day-old broilers. Four isonitrogenous, isocaloric diets balanced for Ca and P were formulated such that oyster shell, snail shell, wood ash and limestone were used as main non-phytate (Ca from other sources apart from plant) calcium sources. Each dietary treatment consisted of 40 birds replicated four times with 10 birds per replicate. A single diet was fed to the broilers throughout the duration of the study which lasted for 8 weeks. Broilers fed diet containing oyster shell as calcium sources recorded the highest (p < 0.05) feed intake of 5863.30 g, while those fed diet containing limestone consumed the least intake (p < 0.05) of 5432.56 g. Occurrence of lameness and evidences of gaits were highest (p < 0.05) for broilers fed diet containing wood ash. Lowest (p < 0.05) Ca and ash retention were recorded for broiler fed diet containing wood ash as Ca sources. Similar tibia ash values were recorded for broilers fed oyster shell, snail shell and limestone. Wood ash inclusion resulted in a low Ca availability hence its inclusion in feeds for broilers should be discouraged. © 2011 Blackwell Verlag GmbH.
Reid, David G.; Mason, Matthew J.; Chan, Benny K. K.; Duer, Melinda J.
2012-01-01
Ibliform barnacles are among the few invertebrate animals harnessing calcium phosphate to construct hard tissue. The 31P solid-state NMR (SSNMR) signal from the shell plates of Ibla cumingi (Iblidae) is broader than that of bone, and shifted by ca 1 ppm to low frequency. 1H–31P heteronuclear correlation (HETCOR) experiments show a continuum of different phosphorus/phosphate atomic environments, close to hydrogen populations with resonance frequencies between ca 10 and 20 ppm. Associated 1H and 31P chemical shifts argue the coexistence of weakly (high 31P frequency, low 1H frequency) to more strongly (lower 31P frequency, higher 1H frequency) hydrogen-bonded hydrogen phosphate-like molecular/ionic species. There is no resolved signal from discrete OH− ions. 13C SSNMR shows chitin, protein and other organic biomolecules but, unlike bone, there are no significant atomic scale organic matrix–mineral contacts. The poorly ordered hydrogen phosphate-like iblid mineral is strikingly different, structurally and compositionally, from both vertebrate bone mineral and the more crystalline fluoroapatite of the linguliform brachiopods. It probably represents a previously poorly characterized calcium phosphate biomineral, the evolution of which may have reflected either the chemical conditions of ancestral seas or the mechanical advantages of phosphatic biomineralization over a calcium carbonate equivalent. PMID:22298816
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krogstad, Daniel V.; Wang, Dongbo; Lin-Gibson, Sheng
Polyelectrolytes are known to greatly affect calcium phosphate (CaP) mineralization. The reaction kinetics as well as the CaP phase, morphology and aggregation state depend on the relative concentrations of the polyelectrolyte and the inorganic ions in a complex, nonlinear manner. This study examines the structural evolution and kinetics of polyaspartic acid (pAsp) directed CaP mineralization at high concentrations of polyelectrolytes, calcium, and total phosphate (19–30 mg/mL pAsp, 50–100 mM Ca2+, Ca/P = 2). Using a novel combination of characterization techniques including cryogenic transmission electron microscopy (cryo-TEM), spectrophotometry, X-ray total scattering pair distribution function analysis, and attenuated total reflectance Fourier transformmore » infrared spectroscopy (ATR-FTIR), it was determined that the CaP mineralization occurred over four transition steps. The steps include the formation of aggregates of pAsp stabilized CaP spherical nanoparticles (sNP), crystallization of sNP, oriented attachment of the sNP into nanorods, and further crystallization of the nanorods. The intermediate aggregate sizes and the reaction kinetics were found to be highly polymer concentration dependent while the sizes of the particles were not concentration dependent. This study demonstrates the complex role of pAsp in controlling the mechanism as well as the kinetics of CaP mineralization.« less
A new synthetic granular calcium phosphate compound induces new bone in a sinus lift rabbit model.
Trbakovic, Amela; Hedenqvist, Patricia; Mellgren, Torbjörn; Ley, Cecilia; Hilborn, Jöns; Ossipov, Dmitri; Ekman, Stina; Johansson, Carina B; Jensen-Waern, Marianne; Thor, Andreas
2018-03-01
The aim of this study was to investigate if a synthetic granular calcium phosphate compound (CPC) and a composite bisphosphonate-linked hyaluronic acid-calcium phosphate hydrogel (HABP·CaP) induced similar or more amount of bone as bovine mineral in a modified sinus lift rabbit model. Eighteen adult male New Zeeland White rabbits, received randomly one of the two test materials on a random side of the face, and bovine mineral as control on the contralateral side. In a sinus lift, the sinus mucosa was elevated and a titanium mini-implant was placed in the alveolar bone. Augmentation material (CPC, HABP·CaP or bovine bone) was applied in the space around the implant. The rabbits were euthanized three months after surgery and qualitative and histomorphometric evaluation were conducted. Histomorphometric evaluation included three different regions of interest (ROIs) and the bone to implant contact on each installed implant. Qualitative assessment (p = <.05), histomorphometric evaluations (p = < .01), and implant incorporation (p = <.05) showed that CPC and bovine mineral induced similar amount of bone and more than the HABP·CaP hydrogel. CPC induced similar amount of bone as bovine mineral and both materials induced more bone than HABP·CaP hydrogel. The CPC is suggested as a synthetic alternative for augmentations in the maxillofacial area. Copyright © 2017 Elsevier Ltd. All rights reserved.
Renal calcinosis and stone formation in mice lacking osteopontin, Tamm-Horsfall protein, or both.
Mo, Lan; Liaw, Lucy; Evan, Andrew P; Sommer, Andre J; Lieske, John C; Wu, Xue-Ru
2007-12-01
Although often supersaturated with mineral salts such as calcium phosphate and calcium oxalate, normal urine possesses an innate ability to keep them from forming harmful crystals. This inhibitory activity has been attributed to the presence of urinary macromolecules, although controversies abound regarding their role, or lack thereof, in preventing renal mineralization. Here, we show that 10% of the mice lacking osteopontin (OPN) and 14.3% of the mice lacking Tamm-Horsfall protein (THP) spontaneously form interstitial deposits of calcium phosphate within the renal papillae, events never seen in wild-type mice. Lack of both proteins causes renal crystallization in 39.3% of the double-null mice. Urinalysis revealed elevated concentrations of urine phosphorus and brushite (calcium phosphate) supersaturation in THP-null and OPN/THP-double null mice, suggesting that impaired phosphorus handling may be linked to interstitial papillary calcinosis in THP- but not in OPN-null mice. In contrast, experimentally induced hyperoxaluria provokes widespread intratubular calcium oxalate crystallization and stone formation in OPN/THP-double null mice, while completely sparing the wild-type controls. Whole urine from OPN-, THP-, or double-null mice all possessed a dramatically reduced ability to inhibit the adhesion of calcium oxalate monohydrate crystals to renal epithelial cells. These data establish OPN and THP as powerful and functionally synergistic inhibitors of calcium phosphate and calcium oxalate crystallization in vivo and suggest that defects in either molecule may contribute to renal calcinosis and stone formation, an exceedingly common condition that afflicts up to 12% males and 5% females.
Computation of Calcium Score with Dual Energy CT: A Phantom Study
Kumar, Vidhya; Min, James K.; He, Xin; Raman, Subha V.
2016-01-01
Dual energy computed tomography (DECT) improves material and tissue characterization compared to single energy CT (SECT); we sought to validate coronary calcium quantification in advancing cardiovascular DECT. In an anthropomorphic phantom, agreement between measurements was excellent, and Bland-Altman analysis demonstrated minimal bias. Compared to the known calcium mass for each phantom, calcium mass by DECT was highly accurate. Noncontrast DECT yields accurate calcium measures, and warrants consideration in cardiac protocols for additional tissue characterizations. PMID:27680414