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PubMed1986

Relationship between bone mineral density of spine and strength of back extensors in healthy postmenopausal women.

We determined the bone mineral density of the lumbar spine and the strength of back extensors in 68 healthy postmenopausal Caucasian women. Bone mineral density of the second to fourth lumbar vertebrae was measured by dual-photon absorptiometry, and back extensor strength was determined with use of a strain-gauge dynamometer. The bone mineral density percentile ranged from 2 to 99%, and back extensor strength ranged from 37 to 145 lb. Statistical analysis demonstrated a significant positive correlation (P = 0.004) between bone mineral density and back extensor strength, even when bone mineral density was corrected for age. Bone mineral density was also significantly positively correlated with body weight (P = 0.003), height (P = 0.001), and arm span (P = 0.008). These data suggest that the strength of back muscles may contribute to the bone mineral density of vertebral bodies.

Aged↗
PubMed1997

Mechanical model for critical strain in mineralizing biological tissues: application to bone formation in biomaterials.

A simple theoretical model for the role of strain energy density in the initial mineralization of soft tissues is presented and used to derive a limit of the allowable strain in tissue engineered biomaterials. The model incorporates the mechanical energy in calcified tissue due to time-varying loads into the more commonly used energetic arguments for mineralization. By using the Voight (equal-strain) and Reuss (equal-stress) composite material models to relate the volumetric density of calcified tissue to overall material modules, two models were developed to assess the effect of an imposed overall material strain on mineralization. A rate equation based on strain energy was used to model the kinetics of mineralization, and the stability of the rate equation was assessed, leading to a limit on overall material strain based on the specific energy for mineralization of soft tissues. The result depended on the stiffness of the material in series with the mineralizing tissue. Taking the stiffness of the material in series with the tissue as infinite lead to a prediction of critical strain for mineralization in the calcifying biological tissue which was the same on the Reuss and Voight models. The interaction of this theoretical model with biological factors and some clinical implications of the model are discussed.

Biocompatible Materials↗
PubMed2003

Mineralization of the basal ganglia: implications for neuropsychiatry, pathology and neuroimaging.

This article examines the evidence for and against the existence of basal ganglia mineralization as a defined clinico-pathological entity. In reviewing the literature on basal ganglia mineralization, this article emphasizes evidence derived from different neuroimaging modalities, genetics, metabolic studies, postmortem series and their possible neuropsychiatric correlates. Relevant articles were collected through Medline and Index Medicus searches. Researchers have encountered multiple difficulties in accepting basal ganglia mineralization as a distinct entity. This syndrome lacks set clinical criteria or a unique etiology; not surprisingly, numerous articles have applied varied definitions. Because many of the reported cases have not been examined postmortem, both the extent and nature of their mineralization remains uncertain. Furthermore, researchers have considered small foci of basal ganglia mineralization a normal phenomenon of aging. However, when brain deposits are extensive, they are associated with a set of age-dependent, progressive clinical symptoms. They include cognitive impairment, extrapyramidal symptoms and psychosis. Most cases are related to abnormalities of calcium metabolism, but rare familial cases of idiopathic origin have been reported. Overabundant mineralization of the brain is judged pathological based on its amount, distribution and accompanying clinical symptoms. Although its relation with calcium dysregulation is well known, modern studies have emphasized abnormalities of iron and dopamine metabolism. The authors suggest that these metabolic abnormalities may link basal ganglia mineralization to psychotic symptomatology.

Basal Ganglia↗
PubMed2001

Individual intake and antiparasitic efficacy of free choice mineral and fenbendazole in range calves.

The current study was conducted to assess the feasibility of fenbendazole (FB) administration to steers in a free choice mineral supplement. Provision of free choice FB reduces the need for handling of animals as well as decreases the level of animal parasitism. Two separate trials were conducted using 400 +/- 19 kg Holstein steers (n=14 and 17) during the months of July and August. Each steer was tagged with a unique electronic identification (EID) ear tag and randomly allocated into one of two groups. The tags worked in conjunction with a mineral feeder equipped with a load cell by registering the steer's EID number every time the animal entered the electromagnetic field. Individual daily mineral intake and feeding times were determined over two 8-day periods of non-medicated mineral (no FB), separated by a 14-day period of medicated mineral (0.55% FB). Fecal samples were collected at the beginning and end of each trial period and were analyzed for gastrointestinal nematode eggs and Giardia cyst. There was a consistently high level of attendance for the entire experimental period, with the exception of the first six days of the adaptation period. There were three preferential times for visiting the mineral feeder, approximately 07:00, 12:00 and 18:00 h. Individual daily mineral and FB intake was 229 +/- 27.21 g/day and 2 +/- 0.14 mg/kg BW/day, respectively, for the 14-day drug delivery period. The levels of fecal nematode eggs and Giardia cysts decreased significantly (<0.01) between pre- and post-sampling, with reductions of 92% for nematode eggs and 85% for Giardia cysts. Free choice medication for the control of gastrointestinal parasites is potentially effective, provided that the appropriate drug concentration, adaptation period, intake level and duration of treatment is utilized.

Administration, Oral↗
PubMed2002

The structure and function of normally mineralizing avian tendons.

The leg tendons of certain avian species normally calcify. The gastrocnemius, or Achilles, tendon of the domestic turkey, Meleagris gallopavo, is one such example. Its structure and biomechanical properties have been studied to model the adaptive nature of this tendon to external forces, including the means by which mineral deposition occurs and the functional role mineralization may play in this tissue. Structurally, the distal rounded, thick gastrocnemius bifurcates into two smaller proximal segments that mineralize with time. Mineral deposition occurs at or near the bifurcation, proceeding in a distal-to-proximal direction along the segments toward caudal and medial muscle insertions of the bird hip. Mineral formation appears mediated first by extracellular matrix vesicles and later by type I collagen fibrils. Biomechanical analyses indicate lower tensile strength and moduli for the thick distal gastrocnemius compared to narrow, fan-shaped proximal segments. Tendon mineralization here appears to be strain-induced, the muscle forces causing matrix deformation leading conceptually to calcium binding through the exposure of charged groups on collagen, release of sequestered calcium by proteoglycans, and increased diffusion. Functionally, the mineralized tendons limit further tendon deformation, reduce tendon strain at a given stress, and provide greater load-bearing capacity to the tissue. They also serve as important and efficient elastic energy storage reservoirs, increasing the amount of stored elastic energy by preventing flexible type I collagen regions from stretching and preserving muscle energy during locomotion of the animals.

Animals↗
PubMed2003

Raman spectroscopy of selected copper minerals of significance in corrosion.

The Raman spectroscopy of selected minerals of the corrosion products has been measured including nantokite, eriochalcite, claringbullite, atacamite, paratacamite, clinoatacamite and brochantite and related minerals. The free energy of formation shows that each mineral is stable relative to copper metal. The mineral, which is formed in copper corrosion, depends on the kinetics and conditions of the reaction. Raman spectroscopy clearly identifies each mineral by its characteristic Raman spectrum. The Raman spectrum is related to the mineral structure and bands are assigned to CuCl stretching and bending modes and to SO stretching modes. Clinoatacamite is identified as the polymorph of atacamite and not paratacamite. Paratacamite is a separate mineral with a similar but different structure to that of atacamite.

Chlorides↗
PubMed2000

Mineral-binding milk proteins and peptides; occurrence, biochemical and technological characteristics.

Minerals and trace elements in cow's milk occur as inorganic ions and salts or form complexes with proteins and peptides, carbohydrates, fats and small molecules. The main mineral binder or chelators of calcium are the caseins, alphas1-casein, alphas2-casein, beta-casein and kappa-casein, but also whey proteins and lactoferrin bind specific minerals like calcium, magnesium, zinc, iron, sodium and potassium. Less documented is the binding of trace elements. Peptides obtained by in vitro or in vivo hydrolysis act as mineral trappers through specific and non-specific binding sites. They may then function as carriers, chelators, of various minerals and thus enhance or inhibit bioavailability. Peptides from milk proteins have found interesting new applications in the food industry as products with improved functionality or as ingredients of dietary products, or used in pharmaceutical industry. Fortification of foods with minerals in a low concentration has for a long time been used in some countries to overcome mineral deficiency, which is an increasing problem in humans. These types of foods are being used to create a new generation of super foods in the industry today.

Animals↗
PubMed2005

XANES investigation of phosphate sorption in single and binary systems of iron and aluminum oxide minerals.

Phosphate sorption on Fe- and Al-oxide minerals helps regulate the solubility and mobility of P in the environment. The objective of this study was to characterize phosphate adsorption and precipitation in single and binary systems of Fe- and Al-oxide minerals. Varying concentrations of phosphate were reacted for 42 h in aqueous suspensions containing goethite, ferrihydrite, boehmite, or noncrystalline (non-xl) Al-hydroxide, and in 1:1 (by mass) mixed-mineral suspensions of goethite/boehmite and ferrihydrite/ non-xl Al-hydroxide at pH 6 and 22 degrees C. X-ray absorption near edge structure (XANES) spectroscopy was used to detect precipitated phosphate and distinguish PO4 associated with Fe(III) versus Al(III) in mixed-mineral systems. Changes in the full width at half-maximum height (fwhm) in the white-line peak in P K-XANES spectra provided evidence for precipitation in Al-oxide single-mineral systems, but not in goethite or ferrihydrite systems. Similarly, adsorption isotherms and XANES data showed evidence for precipitation in goethite/boehmite mixtures, suggesting that mineral interactive effects on PO4 sorption were minimal. However, sorption in ferrihydrite/non-xl Al-hydroxide systems and a lack of XANES evidence for precipitation indicated that mineral interactions inhibited precipitation in these binary mixtures.

Adsorption↗
PubMed2006

Quantifying the effect of soil moisture on the aerobic microbial mineralization of selected pesticides in different soils.

A standardized quantitative approach was developed to reliably elucidate the effect of increasing soil moisture on pesticide mineralization. The mineralization of three aerobically degradable and chemically different 14C-labeled pesticides (isoproturon, benazolin-ethyl, and glyphosate) was studied under controlled conditions in the laboratory at an identical soil density of 1.3 g cm(-3). The agricultural soils used are characterized by (i) large variations in soil texture (sand content 4-88%) and organic matter content (0.97-2.70% org. C), (ii) fairly diverse soil-water retention curves, and (iii) differing pH values. We quantified the effect of soil moisture on mineralization of pesticides and found that (i) at soil water potential < or = -20 MPa minimal pesticide mineralization occurred; (ii) a linear correlation (P < 0.0001) exists between increasing soil moisture (within a soil water potential range of -20 and -0.015 MPa), and increased relative pesticide mineralization; (iii) optimum pesticide mineralization was obtained at a soil water potential of -0.015 MPa, and (iv) when soil moisture approximated water holding capacity, pesticide mineralization was considerably reduced. As both selected pesticides and soils varied to a large degree, we propose that the correlation observed in this study may be also valid in the case of aerobic degradation of other native and artificial organic compounds in soils.

Aerobiosis↗
PubMed2000

Cryopreservation and image enhancement of juvenile and adult dentine mineral.

The inorganic component of bone and related hard tissues is generally described as sheets of uniform needle- and plate-like crystals. However, cryofixation has become the method of choice for ultrastructural studies of bone mineral when ladder-like arrangements of filaments contained within deformable microspheres about 1 microm in diameter are apparently the prime structural feature and are consistent with the optical image. The same methodology has now been applied to mature human dentine in caries-free juvenile and adult teeth. These were fixed, sliced, stained for mineral and examined optically or were snap frozen, fragmented under liquid nitrogen, freeze-substituted with methanol or acetone and embedded without thawing in Lowicryl K4M for electron microscopy. Others were processed by traditional transmission electron microscopy methods. To obtain maximum resolution, the electron micrographs were photographically printed as negatives and image-enhanced by digitisation using a Polaroid Sprint Scan 45 and laser printer. In both optical and cryopreparations of juvenile and adult dentine, mineral microspheres up to 1 microm in diameter, were present in the dentinal tubules and peritubular dentine. Within these objects, the mineral was primarily in the form of sinuous electron dense filaments, 5 nm thick, which had a characteristic periodicity. In these preparations needle-like and plate-like structures were rare. In contrast, after traditional transmission electron microscopy preparation although similar filamentous structures remained, the mineral more generally had the familiar form of needles measuring approximately 50 nm in the long axis. The cryopreserved calcified filaments were apparently particularly densely distributed in the intertubular dentine where their parallel ladder-like arrays often formed highly orientated struts and stays. It was concluded that early dentine mineral has the form of filamentous microspheres and as in bone (and other calcifying tissues and cells) has no specific association with collagen. It was also concluded that these structures compact and deform with maturity into a sub-structural framework which may relate to powerful biomechanical forces transmitted through the tissue. Needle- or plate-like mineral is probably rare in vivo in dentine, only becoming commonplace after extensive chemical processing.

Adolescent↗
PubMed1999

The effect of processing on total organic acids content and mineral availability of simulated cassava-vegetable diets.

Changes in pH, titratable acidity and mineral content (Ca, Fe, Mg, Zn) were estimated in processed cassava products while the mineral content of raw and blanched amaranthus vegetable was determined. pH of fresh cassava (6.5) decreased as total organic acid (0.07%) increased with fermentation period. Fufu and lafun had the lowest pH and the highest total organic acids contents. Fermentation of cassava increased the total calcium and iron contents, reduced magnesium level while zinc remained fairly constant in grated cassava but was reduced when soaked in water (for the preparation of fufu and lafun). Fermentation also increased the availability of these selected minerals in both cassva products and simulated cassava-vegetable diets. Blanching reduced the mineral content of amaranthus vegetable but increased mineral availability. Fermentation of cassava and blanching of vegetables play an important role in making minerals more available and these processing methods should be encouraged to potentially ameliorate the disease states associated with mineral deficiency.

Biological Availability↗
PubMed2004

Influence of a mineral water rich in calcium, magnesium and bicarbonate on urine composition and the risk of calcium oxalate crystallization.

OBJECTIVE: To evaluate the effect of a mineral water rich in magnesium (337 mg/l), calcium (232 mg/l) and bicarbonate (3388 mg/l) on urine composition and the risk of calcium oxalate crystallization. DESIGN: A total of 12 healthy male volunteers participated in the study. During the baseline phase, subjects collected two 24-h urine samples while on their usual diet. Throughout the control and test phases, lasting 5 days each, the subjects received a standardized diet calculated according to the recommendations. During the control phase, subjects consumed 1.4 l/day of a neutral fruit tea, which was replaced by an equal volume of a mineral water during the test phase. On the follow-up phase, subjects continued to drink 1.4 l/day of the mineral water on their usual diet and collected 24-h urine samples weekly. RESULTS: During the intake of mineral water, urinary pH, magnesium and citrate excretion increased significantly on both standardized and normal dietary conditions. The mineral water led to a significant increase in urinary calcium excretion only on the standardized diet, and to a significantly higher urinary volume and decreased supersaturation with calcium oxalate only on the usual diet. CONCLUSIONS: The magnesium and bicarbonate content of the mineral water resulted in favorable changes in urinary pH, magnesium and citrate excretion, inhibitors of calcium oxalate stone formation, counterbalancing increased calcium excretion. Since urinary oxalate excretion did not diminish, further studies are necessary to evaluate whether the ingestion of calcium-rich mineral water with, rather than between, meals may complex oxalate in the gut thus limiting intestinal absorption and urinary excretion of calcium and oxalate.

Adult↗
PubMed2004

Mineral water fortified with folic acid, vitamins B6, B12, D and calcium improves folate status and decreases plasma homocysteine concentration in men and women.

OBJECTIVE: We investigated the effects of mineral water fortified with folic acid, vitamins B(6), B(12), D and calcium on folate concentrations in serum and erythrocytes, serum vitamin B(12) and plasma homocysteine concentrations in free-living subjects. In addition, we investigated the bioavailability of calcium added to mineral water by measuring urinary calcium excretion and serum alkaline phosphatase activity. DESIGN: Randomized, controlled, double-blinded, parallel design. SETTING: Outpatient dietary intervention with free-living subjects in Eastern Finland. SUBJECTS: Altogether, 66 subjects were recruited for the study. In all, 60 subjects completed the study. INTERVENTIONS: The study began with a 2-week run-in period followed by an 8-week intervention period. During the intervention study, subjects consumed mineral water fortified with folic acid (563 microg/day), vitamins B(6) (1 mg/day), B(12) (7.5 microg/day), cholecalciferol (0.6 microg/day) and calcium (563 mg/day) or placebo mineral water. RESULTS: The fortified mineral water increased serum and erythrocyte folate concentrations by 16.1+/-5.6 nmol/l (P<0.001) and 199+/-76 nmol/l (P<0.001), respectively, and decreased plasma homocysteine concentration by 1.6 micromol/l (P<0.001). Urinary calcium excretion and serum alkaline phosphatase activity for 24 h increased significantly (P<0.001 and P=0.01 respectively) in the intervention group. CONCLUSIONS: Mineral water fortified with folic acid, vitamins B(6), B(12) and D and calcium enhanced folate status and reduced plasma homocysteine concentration in normohomocysteinemic subjects without folate deficiency. Indirect measures of calcium and bone metabolism indicated that the calcium used in the fortification of the mineral water was bioavailable.

Adult↗
PubMed2005

Water uptake on mineral dust and soot: a fundamental view of the hydrophilicity of atmospheric particles?

The interaction of water vapour with mineral dust and soot surfaces has been studied in the temperature range 203 K < T < 298 K using a Knudsen cell reactor. For the uptake of water on mineral dust an initial uptake coefficient of gamma(ini) = (6.3 +/- 0.7) x 10(-2) independent of temperature has been determined. In contrast the desorption rate has been found to be strongly temperature dependent with desorption rate constants decreasing from 1 x 10(-3) at 265 K to 1 x 10(-4) at 223 K. In addition, relatively high surface coverages have been determined from which an adsorption enthalpy of -40 kJ mol(-1) is inferred. For the uptake of water on soot the initial uptake coefficient has been found to be independent of temperature with a value of gamma(ini) = (4.7 +/- 0.2) x 10(-2), similar to the case of mineral dust. However, the corresponding desorption rate constants have been found to be three orders of magnitude larger than for mineral dust. Consistent with this finding, low surface coverages with an adsorption enthalpy of -27 kJ mol(-1) have been derived. A comparison of the uptake kinetics and adsorption enthalpies of water on mineral dust and soot leads to the conclusion that water is much stronger interacting with mineral dust than with soot. In terms of a hydrophilicity concept the results suggest, that mineral dust may be regarded as hydrophilic whereas soot is hydrophobic and that fundamental kinetic and thermochemical quantities may be related to that concept.

Adsorption↗
PubMed1988

Decreased bone mineral content in infants of diabetic mothers.

The present study was conducted to test the hypothesis that infants of diabetic mothers (IDMs) have decreased bone mineral content at birth, and whether or not decreased infant bone mineral content in IDMs correlates with poor control of diabetes during pregnancy, maternal bone mineral content, and the development of neonatal hypocalcemia. Forty-five pregnant diabetic women and their infants were enrolled in a prospective trial. In addition, 55 normal newborn infants of nondiabetic mothers were used as controls. Bone mineral content was measured before delivery in all diabetic pregnant patients and at birth in all infants by photon absorptiometry. Bone mineral content was significantly decreased in infants of diabetic mothers compared with control infants and correlated inversely with mean first trimester maternal capillary blood glucose; it did not correlate with cord serum 1,25-dihydroxyvitamin D concentrations. By stepwise multiple regression analysis, in infants of diabetic mothers, bone mineral content correlated inversely with mean first trimester capillary blood glucose and maternal bone mineral content, but did not correlate with maternal blood glycosylated hemoglobin, infant gestational age, infant birthweight or weight percentile, or development of neonatal hypocalcemia.

Blood Glucose↗
PubMed2006

Cooperative deformation of mineral and collagen in bone at the nanoscale.

In biomineralized tissues such as bone, the recurring structural motif at the supramolecular level is an anisotropic stiff inorganic component reinforcing the soft organic matrix. The high toughness and defect tolerance of natural biomineralized composites is believed to arise from these nanometer scale structural motifs. Specifically, load transfer in bone has been proposed to occur by a transfer of tensile strains between the stiff inorganic (mineral apatite) particles via shearing in the intervening soft organic (collagen) layers. This raises the question as to how and to what extent do the mineral particles and fibrils deform concurrently in response to tissue deformation. Here we show that both mineral nanoparticles and the enclosing mineralized fibril deform initially elastically, but to different degrees. Using in situ tensile testing with combined high brilliance synchrotron X-ray diffraction and scattering on the same sample, we show that tissue, fibrils, and mineral particles take up successively lower levels of strain, in a ratio of 12:5:2. The maximum strain seen in mineral nanoparticles (approximately 0.15-0.20%) can reach up to twice the fracture strain calculated for bulk apatite. The results are consistent with a staggered model of load transfer in bone matrix, exemplifying the hierarchical nature of bone deformation. We believe this process results in a mechanism of fibril-matrix decoupling for protecting the brittle mineral phase in bone, while effectively redistributing the strain energy within the bone tissue.

Animals↗
PubMed1993

Variation among individual White-Leghorn hens in the concentration of minerals in the albumen and yolk content of their eggs.

1. The mineral composition of the albumen and yolk was determined in several eggs from each of a number of individual hens from the same White-Leghorn strain. X-ray fluorescent spectrometry was used to undertake two independent series of analyses. A total of 8 minerals (calcium, chlorine, iron, magnesium, phosphorus, potassium, sodium, sulphur) were included in the analyses of the yolk and the same minerals, but excluding iron (which is present in only small amounts), in the albumen. 2. There was considerable variation between individuals in the mineral concentration in their eggs (coefficients of variation ranged between 3.8% for sodium to 19.9% for calcium in the albumen, and between 4.3% for phosphorus to 11.8% for iron in the yolk). 3. At the same time, the moderately high repeatability of mineral concentration (t = 0.4-0.6) in successive eggs from the same hen for several of the minerals analysed is indicative of some positive control by the hen of the mineral composition of her eggs. 4. There was a highly significant correlation (P < or = 0.001) between the mean concentration of potassium in the albumen and the hatchability of the eggs, supporting the claim that a deficiency of potassium in the egg could be the basis of some failures in hatchability. 5. The study also revealed variation among individual birds in the concentration of iron in the yolk which was negatively correlated (P < or = 0.01) with hatchability. No clear basis could be suggested for this variation among individual birds.

Animals↗
PubMed1993

Effect of a soluble polysaccharide (carboxy methyl cellulose) on the absorption of minerals from the gastrointestinal tract of broilers.

1. The effect of an indigestible soluble polysaccharide (carboxy methyl cellulose: CMC) on the absorption of some macro-elements (sodium, potassium, calcium, phosphorus and magnesium) from different segments of the small intestine of broilers was determined. 2. In semi-synthetic diets 0, 5.0 and 10 g/kg cellulose was replaced by CMC on weight basis. These diets were fed to male broilers from 3 to 5 weeks of age. 3. CMC inclusion reduced the rate of mineral absorption throughout the small intestine. The effect of CMC on sodium absorption was more pronounced than the effects on the absorption of the other minerals. 4. The cumulative absorption of all minerals up to the lower jejunum was reduced by dietary CMC. This negative effect of CMC on the absorption of minerals was alleviated in the lower ileum, except for potassium. 5. The concentrations of sodium and magnesium in the chyme supernatant were clearly decreased, while those of calcium and phosphorus were increased by dietary CMC inclusion. Taking the mineral concentrations in the total chyme into account, the solubilities of calcium, phosphorus and magnesium in the ileum were increased by dietary CMC. The solubilities of sodium and potassium were not increased. 6. The reduced cumulative absorption of minerals from the gastrointestinal tract with increasing dietary concentrations of CMC, was probably caused by the higher intraluminal viscosities in the small intestine. It is not likely that either the intestinal pH, or the time food was retained in successive gastrointestinal segments, will have affected mineral absorption negatively in any segment.

Animals↗