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The current study was conducted in the laboratories of the Marsh Research Center, the Center for Genetic Diseases, and Al-Hussein Teaching Hospital during the period from June 2022 to January 2023, with the aim of studying the genetic polymorphism of the haptoglobin (Hp) gene and its relationship to levels of essential minerals in patients with sickle cell anemia. Hepatitis C, and sickle cell anemia with hepatitis C. a total of 130 participants were classified, (40) control groups, (40) patients with sickle cell anemia, (40) patients with hepatitis C, and (10) sickle cell patients with hepatitis C . DNA was isolated and polymerase chain reaction (PCR) performed using genotype-specific primers for the three regions of the haptoglobin gene, and genotypes were determined after electrophoresis on agarose gels and determining the amplified fraction of each allele.Iron, copper, zinc, and chromium in blood serum were determined by flame atomic absorption spectrometry according to the manufacturer's procedures. The study found that the Hp2-2 genotype was more common in patients with sickle cell anemia, hepatitis, and both sickle cell anemia and hepatitis compared to the healthy control group.However, there were no significant differences in this genotype between the three diseases. In all patients, the level of iron and copper in the serum was significantly higher compared to the control group.and In all patients, the study showed a significant depletion of serum zinc compared to the control group,And no significant difference in serum chromium concentration between the patients and the control group.Regarding the polymorphisms of haptoglobin, the study did not find a statistically significant relationship between these genetic variations and the levels of iron, copper, and chromium in any of the participant groups. However, the concentrations of zinc differed between the three types of haptoglobin. [ABSTRACT FROM AUTHOR]

Ectopic mineralization refers to the deposition of mineralized complexes in the extracellular matrix of soft tissues. Calcific aortic valve disease, vascular calcification, gallstones, kidney stones, and abnormal mineralization in arthritis are common examples of ectopic mineralization. They are debilitating diseases and exhibit excess mortality, disability, and morbidity, which impose on patients with limited social or financial resources. Recent recognition that inflammation plays an important role in ectopic mineralization has attracted the attention of scientists from different research fields. In the present review, we summarize the origin of inflammation in ectopic mineralization and different channels whereby inflammation drives the initiation and progression of ectopic mineralization. The current knowledge of inflammatory milieu in pathological mineralization is reviewed, including how immune cells, pro-inflammatory mediators, and osteogenic signaling pathways induce the osteogenic transition of connective tissue cells, providing nucleating sites and assembly of aberrant minerals. Advances in the understanding of the underlying mechanisms involved in inflammatory-mediated ectopic mineralization enable novel strategies to be developed that may lead to the resolution of these enervating conditions. [ABSTRACT FROM AUTHOR]

Matrix vesicles (MVs) are extracellular membrane-bound vesicles of about ~ 50–200 nm in diameter that play a role in the bio-mineralization process of hard tissue formation. The present review is based on the empirical phenomenon of primary mineralization process via matrix vesicle-mediated mechanism with special reference to crystal ghosts as well as the mechanism on the organic–inorganic relationship between matrix vesicles and crystal ghosts, and the transformation that these structures undergo during bio-mineralization. [ABSTRACT FROM AUTHOR]

The aim of this study was two-fold: (1) identify suitable bio-indicators to assess elemental status in elephants using captive elephant samples, and (2) understand how geochemistry influences mineral intake. Tail hair, toenail, faeces, plasma and urine were collected quarterly from 21 elephants at five UK zoos. All elephant food, soil from enclosure(s), and drinking water were also sampled. Elemental analysis was conducted on all samples, using inductively coupled plasma mass spectrometry, focusing on biologically functional minerals (Ca, Cu, Fe, K, Mg, Mn, Na, P, Se and Zn) and trace metals (As, Cd, Pb, U and V). Linear mixed modelling was used to identify how keeper-fed diet, water and soil were reflected in sample bio-indicators. No sample matrix reflected the status of all assessed elements. Toenail was the best bio-indicator of intake for the most elements reviewed in this study, with keeper-fed diet being the strongest predictor. Calcium status was reflected in faeces, (p 0.019, R2 between elephant within zoo - 0.608). In this study urine was of no value in determining mineral status here and plasma was of limited value. Results aimed to define the most suitable bio-indicators to assess captive animal health and encourage onward application to wildlife management. [ABSTRACT FROM AUTHOR]

Nondairy fermented products, such as fruit and vegetable juices, are gaining popularity among consumers worldwide for health‐related and economic reasons. The purpose of this study was to determine the changes in microbiological quality; antimicrobial and antioxidant activity; and phenolic, vitamin C, minerals, and cadmium content occurring during spontaneous fermentation of curly kale juice. The fermentation process contributed to a significant growth of lactic acid bacteria, enterococci, and yeasts, while no pathogens of Escherichia coli and Salmonella spp. were observed. The antimicrobial properties of the obtained juice improved during fermentation for all indicator microorganisms. Total phenolic content and antioxidant activity increased from 48 to 116 mg gallic acid equivalent/100 mL and from 4.5 to 6.8 mM Trolox/100 mL, respectively, while the content of vitamin C decreased. The results indicated that 100 mL of juice provided a significant contribution to the recommended mineral intake. Moreover, the content of heavy metal Cd was within acceptable limit (6 µg/kg). Overall, our findings indicate that fermented curly kale juice may become popular in the functional food sector, especially among vegetarians and consumers with lactose intolerance or allergy to milk proteins. Practical Application: As the market for fermented fruit and vegetable products grows, new plant materials rich in biologically active compounds are being sought. Considering the high demand for sauerkraut, the fermentation of other cruciferous vegetables seems interesting. One example is curly kale, which has been classified as "superfood" due to its numerous beneficial health properties, such as strong antioxidant activity, high vitamins, and minerals content. In addition, a market niche exists due to a lack of fermented green curly kale products on the market, making our study particularly relevant. [ABSTRACT FROM AUTHOR]

Little is known about the prevalence and motives of supplement use among elite young athletes who compete on national and international levels. Therefore, the current survey was performed to assess information regarding the past and present use of dietary supplements among 164 elite young athletes (16.6 ± 3.0 years of age). A 5-page questionnaire was designed to assess their past and present (last 4 weeks) use of vitamins, minerals, carbohydrate, protein, and fat supplements; sport drinks; and other ergogenic aids. Furthermore, information about motives, sources of advice, supplement sources, and supplement contamination was assessed. Eighty percent of all athletes reported using at least 1 supplement, and the prevalence of use was significantly higher in older athletes (p < .05). Among supplement users, minerals, vitamins, sport drinks, energy drinks, and carbohydrates were most frequently consumed. Only a minority of the athletes declared that they used protein/amino acids, creatine, or other ergogenic aids. Major motives for supplement use were health related, whereas performance enhancement and recommendations by others were less frequently reported. Supplements were mainly obtained from parents or by athletes themselves and were mostly purchased in pharmacies, supermarkets, and health-food stores. Among all athletes, only 36% were aware of the problem of supplement contamination. The survey shows that supplement use is common and widespread among German elite young athletes. This stands in strong contrast to recommendations by leading sport organizations against supplement use by underage athletes. [ABSTRACT FROM AUTHOR]

This study compared tibial bone and muscle geometry and total body and regional bone mineral content (BMC) in elite female adolescent middle-distance runners (n = 20, age: 16 ± 1.7 years) and age- and sex-matched controls (n = 20, 16 ± 1.8 years) using magnetic resonance imaging and dual-energy X-ray absorptiometry. Significant advantages were found in athletes compared with controls in bone and muscle geometric values for distal tibial cortical, medullary cavity, distal tibial total muscle and dorsi flexor muscle compartment cross-sectional area, and regional BMC. Results imply mechanical loads associated with middle-distance running might be beneficial to musculoskeletal health in adolescent females. [ABSTRACT FROM AUTHOR]

Objective: This in vitro study aimed to evaluate the effect of bleaching agents on dentin microhardness during and after bleaching. Method and materials: Specimens were randomly assigned to seven groups (n = 15): Nite White Excel 2 Z [NW] 10% and 22%; Rembrandt [REM] 10% and 22%; Opalescence [OPA] 10% and 20%; and a placebo agent. The 42-day whitening treatment consisted of daily application of the agents to the dentin surfaces for 8 hours, followed by immersion in artificial saliva for 16 hours. After the bleaching treatment, specimens were kept immersed in artificial saliva for 14 days. Microhardness was measured at baseline, 8 hours, and 7,14. 21,28, 35, and 42 days of bleaching and during the posttreatment period (7 and 14 days). Results: The analysis of variance for split-plot showed a significant effect on the interaction between bleaching agent and time. Tukey's test and regression analyses revealed that during the bleaching period, the agents NW 10%, NW22%, and OPA 20%, which did not differ from each other, did not alter dentin microhardness, showing constant microhardness values. There were no differences among REM 10%, REM 22%, and OPA 10%, which showed significant reductions in microhardness after day 14 compared to other agents. After bleaching procedures, there was an increase in dentin microhardness for all groups. Conclusion: Throughout the bleaching treatment, depending on the agent applied, dentin showed a transitory decrease in microhardness values. In the posttreatment period, artificial saliva presented a remineralizing effect on the bleached surfaces. [ABSTRACT FROM AUTHOR]

This study aimed to determine the relationship between bone mineral content, habitual physical activity, and calcium intake in children. Fifty-seven children, aged 8-11 years, wore pedometers for seven days to assess activity. Calcium intake was estimated by a 4-day food diary. Bone mineral content (BMC) and areal density (BMD) were measured at the total proximal femur and femoral neck using dual energy X-ray absorptiometry. Regression analysis was used to assess contributions of physical activity and calcium intake to BMC, residualized for bone area and body mass. Physical activity explained 11.6% of the variance in residualized BMC at the proximal femur and 14.3% at the femoral neck (p < 0.05). Calcium intake added to the variance explained at the proximal femur only (9.8%, p < 0.05). This study provides evidence for an association between BMC and habitual physical activity. [ABSTRACT FROM AUTHOR]

The correlates and determinants of total body (TB), femoral neck (FN), greater trochanter (GT) and leg areal bone mineral density (aBMD), and FN volumetric (vol) BMD were investigated in 42 healthy 6-10-year-old girls. Predictor variables included age, height, weight, lean tissue mass (LTM), fat mass, percent body fat, physical activity level, calcium intake, isokinetic knee flexion and extension strength and endocrine (E[sub 2]) status. Bone density and body composition were determined by dual energy-x-ray absorptiometry (DEXA), and pubertal status was self-determined. LTM, weight, age, knee extensor strength and fat mass were significantly correlated (Pearson correlation coefficients; 0.36 ≤ r ≥ 0.62) with TBaBMD. These same variables with the addition of height and knee flexor strength were significantly correlated (0.33 ≤ r ≥ 0.77) with leg aBMD. Only LTM correlated significantly with FNaBMD and none of the independent variables correlated with FNvolBMD or GTaBMD. Only LTM entered as a significant predictor in multiple linear regression analysis (R² = 46.7%) for TBaBMD. In conclusion, estradiol status, dietary calcium intake and physical activity level appeared not to be important predictors of B MD in this population, whereas LTM was consistently correlated with most BMD measures and was the single significant determinant of TBaBMD in this study. [ABSTRACT FROM AUTHOR]

Presents several abstracts in the August 2000 issue of the 'Pediatric Exercise Science, journal. 'Days Needed for Physical Activity Monitoring,' by S.G. Trost, R.R. Pate, P.S. Freedson and J.F. Sallis; 'Correlations With Bone Mineral Density in Adolescents,' by K.A. Witzke and C.M. Snow; 'Exercise Factors Influencing Serum Lipid Profile,' by K. Tolfrey, I.G. Campbell and A.M. Jones; 'Longitudinal Changes in Running Economy,' by J.R. Welsman and N. Armstrong.

Osteoporosis is a major public health problem affecting more than 200 million people worldwide. The use of different animal models, for the study of its pathophysiology and treatments, is important being actually the ovariectomized rat the most widely used; although this model has several problems due its small size, lack of true closure of epiphyseal plate and bone differences with humans. This review is aimed at summarizing the most common methods published for osteoporosis induction in rabbits as model for human disease with their advantages and disadvantages. The paper shows the advantages of the use of this specie compared with the rat. All the techniques seemed to achieve the osteoporotic condition, but the one which obtained the most consistent bone mineral reduction in less time was the combination of surgery and corticoid treatment. The conclusion of the review was that rabbits are promising as a model of osteoporosis research because of their size, haversian remodelling and closure of epiphyseal plate, which solve some of the problems of the rat model. There are different techniques in the literature used to achieve the osteoporotic condition with diverse results, but there is a lack of consensus as to the best one. [ABSTRACT FROM AUTHOR]

• Postoperative patellar strain is correlated with preoperative BMD and BMI. • Postoperative resurfaced patella volume is not correlated with patellar strain. • Mapping of strain versus BMD and BMI to evaluate the risk of patella complications. Patella-related complications after total knee arthroplasty (TKA) remain a major clinical concern. Previous studies have suggested that increased postoperative patellar bone strain could be related to such complications, but there is limited knowledge on patellar strain after TKA. The objective of this study was to predict patellar bone strain after TKA and evaluate correlations with various preoperative data. Fourteen TKA patients with a minimum follow-up of one year were included in this study. Using preoperative CT datasets, preoperative planning, and postoperative X-rays, a method is presented to generate patient-specific finite element models after virtual TKA. Patellar kinematics and forces were predicted during a squat movement, and patellar bone strain was evaluated at 60° of knee flexion. Strain varied greatly among patients, but was strongly negatively correlated (r = −0.85, p < 0.001) with bone mineral density (BMD) and moderately positively (r = 0.54, p = 0.05) with body mass index (BMI). The BMI/BMD ratio explained 87% of strain, and should be further investigated as a potential risk factor for clinical complications. This study represents a preliminary step towards the identification of patients at risk of patellar complications after TKA. [ABSTRACT FROM AUTHOR]

The article demonstrates several difficulties linked with interpreting three-dimensional architecture of lesions which involves the alveolar process, via radiographs. Two cases involving a well defined ovoid and poorly defined radiolucent area comparing the radiographic view to bony defects on dry skull is presented. Some factors including degree of decalcification of bone influencing the aspect of radiolucent pathologic processes is given. It is reported that radiographs of lateral periodontal cysts showed a well defined round radiolucent between apex and cervical margin of tooth. As cited, it is difficult to determine the origin of lesion without surgical interference and if such process reveals cortical bone erosion with periodontal ligament, the cyst is likely to be gingival.

Phosphorus (P) is essential for building and maintaining a healthy and strong skeleton. Moreover, dietary P supply may play a role for bone turnover, and the excretion of bone turnover metabolites may be useful as markers for sufficient dietary P supply. The objective was to study the long-term effects of low, medium, and high dietary P supply on bone metabolism in terms of serum concentration and urinary excretion of bone turnover components and metabolites in healthy growing- finishing pigs compared with bone mineral content (BMC) and bone mineral density (BMD) of humerus and femur. Pigs were fed diets containing low [LP; 4.1 g/kg dry matter (DM)], medium (MP; 6.2 g/kg DM), or high dietary P (HP; 8.9 g/kg DM) from 39.7 kg body weight (BW) until slaughter at 110 kg BW. Urine and blood were collected at 40, 70, and 110 kg BW while bones were collected at slaughter. Serum was analyzed for osteocalcin (OC), bone alkaline phosphatase (BAP), and C-terminal telopeptides of type I collagen (CTX-I), whereas urine was analyzed for pyridinoline (PYD), deoxypyridinoline (DPD), CTX-I, hydroxylysine (HYL), galactosyl-hydroxylysine (GAL-HYL), glycosyl-galactosyl-hydroxylysine (GLC-GAL-HYL), and hydroxyproline (HYP). Humerus and femur were analyzed for BMC and BMD. The LP diet caused reduced OC and increased BAP and CTX-I concentrations in serum. Furthermore, BAP was increased in response to the HP diet. Urine metabolites of bone resorption were all increased in pigs fed the LP diet, but only a few responses were obtained in response to the HP diet. Furthermore, age-related decreases were identified for BAP, HYL, GAL-HYL, and GLCGAL- HYL. Bone mineral content and BMD were markedly lowered in pigs fed the LP diet but were not affected in pigs fed the HP diet. In conclusion, OC, BAP, and CTX-I in serum have proved useful for P adequacy in growing-finishing pigs. In addition, urine bone resorption metabolites have also proved useful for P adequacy and analysis of PYD, DPD, and CTX-I was considered to be the most relevant markers due to their specificity for bone and their negative correlation with BMD, BMC, ash, calcium (Ca), and P contents. Finally, DPD may be the preferred marker in long-term P feeding assessments. [ABSTRACT FROM AUTHOR]

Lower Cambrian assemblages of phosphatic and chitinous tubular fossils of probable cnidarian affinities were recovered from the Yanjiahe, Shuijingtuo and Shipai formations in the Three Gorges area, South China. Terreneuvian Cambrorhytium cf. C . major co-occur with an unnamed taxon in the Yanjiahe Formation. They can be compared with specimens from the Ediacaran Miaohe Fauna in the Three Gorges area. The most abundant and diversified cnidarian assemblages, including Cambrorhytium gracilis n. sp., Cambrorhytium cf. major , Cambrorhytium minor , Sphenothallus songlinensis , Sphenothallus taijiangensis ?, Sphenothallus kozaki , ? Sphenothallus sp., ? Byronia sp., and ? Mackenzia sp. are reported from the overlying, Cambrian Stage 3–4, Shuijingtuo and Shipai formations. These new fossils show previously unknown evidence for cnidarian affinities, such as an attachment disk, clonal clusters and probable budding structures. These diversified assemblages of probable cnidarian fossils further fill major gaps in the Cambrian record of stem metazoans and document associated early evolutionary patterns. In addition, our discovery suggests that along with sponges, these tubular fossils represent another important component of benthic ecosystems that colonized often dysoxic, deep-settings during the Cambrian explosion. The observed increases of average body-size and biomineralization among these probable cnidarians are tentatively linked to oxygenation of deep oceanic settings and appearance of predatory pressure during the Ediacaran–Cambrian transition, respectively. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize the serum concentration of macrominerals of Blackbelly sheep under free grazing conditions in Ecuadorian Amazon. Twenty-two Blackbelly sheep, belonging to the Centro de Investigación, Posgrado y Conservación de la Biodiversidad Amazónica (CIPCA) and raised under the same environmental, nutritional and managerial conditions, were studied during the summer period April-June. Blood samples were taken from the coccygeal vein 30 days before lambing, at lambing time and at 30 and 60 days after lambing. Mg2+, Na and P variables showed no significant differences (P>=0.05) with time. However, Ca2+ showed significant differences (P>=0.05), with changes at lambing time and 30 days after. In conclusion, there is a serum deficit of Ca2+ and P in the studied population of Blackbelly sheep under free grazing conditions of Ecuadorian Amazonia during all the period. Supplementation should be selective for these minerals. [ABSTRACT FROM AUTHOR]

The minerals are nutritive substances that are found in the food ration and in the body, in the form of anorganic and organic compounds. Although the mineral substances in the body represent only 4 - 5 % of the body's weight, they are indispensable for the maintaining of the health condition. In the body the mineral substances meet important functions, biochemical and physiological. In the body some minerals are found in larger quantities, bearing the denomination of macro minerals. In this category we can include the mineral substances that include the elements: Calcium, Phosphorus, Sodium, Potassium, Chlorine and Magnesium. [ABSTRACT FROM AUTHOR]

Lamb meat represents an important source of nutrients for humans worldwide. However, nutritional value of lamb meat, and particularly that obtained from suckling lambs, has been scarcely investigated in comparison to other categories of meat. The study aimed to provide some basic insights into proximate and mineral composition of lamb meat and to disclose some important sources of its variability. Three Croatian indigenous insular sheep breeds were included in the study: Rab sheep, Cres sheep, and Krk. The lambs were reared in outdoor insular environment where lambs were fed exclusively by suckling their mothers and by grazing wild grown vegetation. It has been determined that gender significantly affected fat (p<.001) and moisture ratio (p<.05), and had no effect on concentration of the examined minerals, except Zn (p<.01). The factor composed of breed and environment significantly affected moisture ratio (p<.001), fat ratio (p<.01), and concentrations of Ca, Na, Cu, and Mn (p<.001), Zn (p<.01), and K (p<.05). The concentrations of Mn and Ca were by far the most influenced by breed-environment effect. The results of the study evidenced that factor composed of breed and environment represents important source of variability of nutritional value of lamb meat produced in extensive rearing systems. [ABSTRACT FROM AUTHOR]

The objectives of the study were to quantify the dentine mineral concentration (DMC) in teeth restored conventionally, according to the atraumatic restorative treatment (ART) and ultraconservative (UCT) protocols (open cavities and small ART restorations), and the DMC underneath the open cavities of teeth managed by UCT versus nontreated, open cavities. We studied 50 teeth with restorations/open cavities, 39 restored teeth (9 by conventional restorative treatment [CRT], 17 by ART, and 13 by UCT) and 16 teeth with open cavities. Each restoration/open cavity was scanned using microcomputed tomography, with 3 hydroxyapatite disks with respective densities of 1.24, 1.33, and 1.57 g/cm3 as a reference. Images were reconstructed and the greyscale images were converted into DMC values. For each restoration/open cavity, 15 measurements of dentine immediately underneath and from the corresponding area in sound dentine were taken. DMC was expressed as a percentage of the DMC of sound dentine. ANOVA and the Student t test were used for statistical analysis. The mean DMC underneath restorations of the ART protocol group (98.93%) was statistically significantly higher than that of the UCT protocol group (91.98%), but not of the CRT protocol group (91.33%). On multiple surfaces, mean DMC in the axial area (94.32%) was statistically significantly higher than in the gingival area (92.80%). The mean DMC of open cavities managed by UCT protocol (89.05%) was statistically significantly higher than in nontreated open cavities (83.90%). In conclusion, a dentine-hypermineralized area underneath ART restorations was observed. Managing open cavities with a toothbrush and fluoride toothpaste (the UCT protocol) resulted in higher mineralized dentine underneath the cavity than in nontreated open cavities. [ABSTRACT FROM AUTHOR]

The present study estimated the level of some macro and micro minerals in female dogs with mammary gland tumors fed with different habitual diets. Female dogs bearing malignant mammary tumors were divided into two groups; group-I (n=12) fed only with balanced commercial diet and group-II (n=12) fed only with homemade diet. Ten physiologically healthy female dogs were taken as control. Trace elements viz. iron, copper, zinc and manganese were estimated in plasma and mammary tumor tissues. Calcium and phosphorus were exclusively estimated in plasma. Plasma concentrations of iron, copper and calcium were found to be significantly (p<0.05) elevated in homemade diet group as compared to control. However, the level of zinc, manganese and phosphorus in plasma of female dogs fed only with homemade diet was decreased (p<0.05) in comparison to control. The mammary gland tissue analysis of iron, copper, zinc and manganese has revealed that their level was found to be significantly (p<0.05) increased in mammary gland tumor tissues of both commercial and homemade diet group as compared to normal mammary tissues. The study concluded that, homemade diet significantly influence the plasma mineral status in the tumor bearing female dogs. However, mineral levels in mammary tumor tissues were altered irrespective of diet types. [ABSTRACT FROM AUTHOR]

The effects of prophylactic oral Ca supplementation on blood mineral status and markers of energy balance were evaluated on 205 multiparous Jersey cows at a commercial dairy. Postpartum, cows were systematically assigned to control (n = 105) or oral Ca supplementation (CaOS; 50 to 60 g of Ca as boluses; n = 100) at 0 and 1 d in milk (DIM). Blood samples for analysis of serum minerals (Ca, P, Mg, K, Na, Fe, Zn, and Cu) were collected before and 1 h after treatment at 0 and 1 DIM, and at 2 DIM. Urine pH was measured immediately before and 1 h after treatment administration (n = 96). A subset of 74 cows was evaluated for plasma glucose and fatty acid concentrations at 0, 1, and 2 DIM. Cows were classified according to their initial calcemic status (Ca status) as normocalcemic (NC; serum Ca >2.12 mmol/L) or subclinically hypocalcemic (SCH; serum Ca ≤2.12 mmol/L). Average serum Ca concentration was higher in CaOS than control cows (2.12 vs. 2.06 mmol/L); this treatment effect was higher for SCH [CaOS (2.03 mmol/L); control (1.89 mmol/L)] than NC cows [CaOS (2.22 mmol/L); control (2.22 mmol/L)]. The incidence of subclinical hypocalcemia was lower for CaOS than control cows (53 vs. 65%); however, at 2 DIM the prevalence of subclinical hypocalcemia tended to be higher for CaOS cows, mostly because it was higher for CaOS-NC than control-NC cows (70 vs. 25%). Urine pH was lower for CaOS than control cows (6.10 vs. 7.04). Lower serum Mg concentration was detected for CaOS-SCH (1.06 mmol/L) than for control-SCH (1.10 mmol/L) cows. Cows in the CaOS group had higher serum K (4.68 vs. 4.53 mmol/L), lower plasma glucose (2.97 vs. 3.10 mmol/L), and at 2 DIM higher plasma fatty acid concentrations (0.43 vs. 0.35 mmol/L) than control cows. Our results showed that postpartum serum Ca concentration increases with oral Ca supplementation, but calcemic status influenced treatment response. Future studies should evaluate the long-term implications on production and reproduction of oral Ca supplementation in Jersey cows. [ABSTRACT FROM AUTHOR]

The aim of our study was the detailed characterization of calcium deposits in ligamenta flava. The use of microcomputed tomography allowed extending the routine medical investigations to characterize mineral grains in the microscopic scale. A possible connection between spinal stenosis and ligament mineralization was investigated. The studies were carried out on 24 surgically removed ligamentum flavum samples divided into control and stenosis groups. Physicochemical characterization of the inorganic material was performed using X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. The minerals were present in 14 of 24 ligament samples, both in stenosis and control groups. The inorganic substance constitutes on average ~0.1% of the sample volume. The minerals are scattered in the soft tissue matrix without any regular pattern. It was confirmed that minerals possess an internal structure and consist of the organic material and small inorganic grains mixture. The physicochemical analyses show that the predominant crystalline phase was hydroxyapatite (HAP). In the stenosis group calcium pyrophosphate dehydrate (CPPD) was identified. Both structures were never present in a single sample. Two different crystal structures suggest two independent processes of mineralization. The formation of CPPD may be treated as a more intense process since CPPD minerals are characterized by bigger values of the structural parameters and higher density than HAP deposits. The formation of HAP minerals is a soft tissue degeneration process that begins, in some cases, at early age or may not occur at all. Various density and volume of mineral grains indicate that the mineralization process does not occur in a constant environment and proceeds with various speeds. The formation of minerals in ligamenta flava is not directly associated with diagnosed spinal canal stenosis. [ABSTRACT FROM AUTHOR]

Trace elements selenium, copper, and zinc are essential minerals for the human body. One of the means to increase the micronutrient content in diets is to add them to food raw materials, for example, to enrich grain with micronutrients during malt production. To obtain rye malt, 3 kg grain was soaked in 101 water with addition of three mineral salts -- sodium selenate (Na2SeO4), copper sulphate (CuSO4 5H2O), and zinc sulphate (ZnSO4 7H2O) at different concentrations and different combination of salts. The concentration of selenium, copper, and zinc was determined in rye malt. The obtained results were used to calculate the degree of assimilation of trace elements in rye malt. The interaction of trace elements selenium/copper and copper/zinc was studied. The total amount of selenium, copper, and zinc was analysed by inductively coupled plasma mass spectrometry (ICP-MS). Sample preparation for elemental analysis was performed by wet acid digestion in a closed microwave mineralisation system. The selenium assimilation degree in rye malt was within 10.6 to 12.2%. Accordingly, copper assimilation was 32.8 to 38.0% and zinc 49.3 to 57.0%. Simultaneous presence of selenium/copper and copper/zinc during rye grain soaking promoted the assimilation of each mineral, compared with only one mineral additive. [ABSTRACT FROM AUTHOR]

Abstract: We used spectrometry to study variation in the contents of minor (B, Cu, Fe, Mn and Zn) and major essential elements (Ca, K, Mg, Na and P) in the muscle tissue and digestive glands of Octopus vulgaris after 1, 2, 4 or 8 days of starvation and in fed controls. The contents of the major essential elements remained constant during 8 days of starvation. Na was the principal element found in both tissues, followed by K, P and Mg. The contents of the minor essential elements were higher in the digestive gland than in the muscle tissue, with increased contents of Fe, Mn and Zn (p < .05) during starvation, confirming the high capacity of this organ to accumulate trace minerals. In muscle tissues, B, Fe and Mn contents were lower and Cu and Zn contents higher, in starved animals than in fed animals (p < .05). Significant negative correlations between the digestive gland index and the contents of Cu, Fe and Zn suggested that the loss of weight of the digestive gland during starvation is responsible for this increase in mineral concentration. This and further information on variation in mineral content will help to optimize performance of diets formulated for the octopus. [ABSTRACT FROM AUTHOR]

Purpose/Aim: The most common kidney stone composed of calcium oxalate forms on interstitial calcium phosphate mineral known as a Randall’s plaque (RP). Due to limited information about events leading to the initial deposition of nanometer size interstitial calcium phosphate pre-clusters, there continues to be a debate on the initial site of calcium phosphate deposition and factors leading to stone formation. Materials and Methods: High-resolution X-ray micro-computed tomography (CT), and light and electron microscopy techniques were used to characterize human renal pyramids and five representative kidney stones with identifiable stems. Mineral densities of mineralized aggregates within these specimens were correlated with micro- and ultra-structures as seen using light and electron microscopy techniques. Results: The earliest detectable biominerals in the human renal papilla were proximal intratubular plate-like calcium phosphate deposits. Unoccluded tubules in stems connected to calcium phosphate stones were observed by electron microscope and X-ray micro-CT. These tubules were similar in diameter (30-100 μm) and shape to those observed in the distal regions of the renal papilla. Conclusions: Observations were patterned through a novel and unified theory of stepwise-architecture guided biomineralization (a combination of smaller structures leading to a larger but similar structural framework). A plausible stepwise progression in renal biomineralization is proposed; proximal intratubular calcium phosphate deposits can lead to interstitial yet calcium phosphate rich RP and mature into a stem on which a calcium oxalate stone grows within the collecting system of a kidney. [ABSTRACT FROM AUTHOR]

Bone and dentin development requires temporal and spatial deposition of calcium phosphate mineral. A host of proteins works in concert to contribute to this tightly regulated process while malfunction in this scheme often leads to pathological defects. We have reported earlier that DMP1 stimulation of preosteoblasts leads to calcium release from internal Ca2+ stores and this store depletion is sensed by the ER Ca2+ sensor STIM1 (stromal interaction molecule 1). In this study, we first assessed the temporal and spatial localization of STIM1 protein during the development of bone and dentin by immunohistochemical methods. We further analyzed the function of STIM1 by establishing a stable MC3T3-E1 cell-line by overexpressing STIM1 (MC3T3-E1/STIM1 OE). Under mineralizing conditions, STIM1 overexpressing cells showed increased calcium deposits with higher expression of key osteogenic markers, such as Runx2 and type I collagen, BMP4 when compared with the control cells. Our results demonstrate that during mineralized matrix formation STIM1, the key ER sensor protein, can promote cellular differentiation in the presence of extracellular calcium. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between mineral concentrations, and the relationship of mineral concentrations with physicochemical characteristics in muscles were investigated using the Longissimus thoracis (LT) muscle of 44 Japanese Black steers. We determined moisture content, fat content, meat color, fatty acid composition and mineral concentrations in the LT muscle. Magnesium (Mg), potassium (K) and zinc (Zn) concentrations had negative correlations with fat content, but sodium (Na), manganese (Mn), copper (Cu) and molybdenum (Mo) concentrations were not correlated with fat content. The concentrations of Mg, Mn, Fe, Cu and Zn largely and positively contributed to the first principal component of mineral concentrations. Because the red muscle was rich in these minerals compared to the white muscle, the variation of these minerals probably results from the abundance of red fibers in the LT muscle. The concentration of K was positively correlated with moisture content but Na concentration was not related to moisture content, suggesting that the intracellular fluid volume can largely affect moisture content. The results of the present experiment suggest that mineral concentrations reflect some traits such as not only fat content but also the composition of myofiber type and the intracellular fluid volume in the LT muscle of Japanese Black cattle. [ABSTRACT FROM AUTHOR]

Aims The aim of this work is to analyse the effect of pH, fungal identity and P chemical nature on microbial development and phosphatase release, discussing solubilization and mineralization processes in P cycling. Methods and Results P solubilizing fungi ( Talaromyces flavus, T. helicus L, T. helicus N, T. diversus and Penicillium purpurogenum) were grown under three pH conditions (6, 6·5 and 8·5) and with different inorganic (calcium, iron, aluminium and rock) and organic (lecithin and phytate) P sources. P solubilization, mineralization, growth and phosphatase production were recorded. Acid and neutral environments maximized fungal development and P recycling. P chemical nature changed the phosphatases release pattern depending on the fungal identity. Acid phosphatase activity was higher than alkaline phosphatases, regardless of pH or sample times. Alkaline phosphatases were affected by a combination of those factors. Conclusions P chemical nature and pH modify fungal growth, P mineralization and solubilization processes. The underlying fungal identity-dependent metabolism governs the capacity and efficiency of P solubilization and mineralization. P solubilization and mineralization processes are interrelated and simultaneously present in soil fungi. Significance and Impact of the study This study constitutes a reference work to improve the selection of fungal bioinoculants in different environmental conditions, highlighting their role in P cycling. [ABSTRACT FROM AUTHOR]

Background The high rate of changes in the composition of saliva can be used for the monitoring of various biorhythms in order to study the physiological characteristics of the human body. Research objective The study of the dynamics of the near-24-h mineral composition of saliva in men and women. Methods The study involved 20 men and 20 women, age 23.1 ± 0.9 years. Saliva samples were collected every 3 h during the day within 10 min. The mineral composition of saliva was defined by the capillary electrophoresis technique. The cross-group differences were evaluated using the non-parametric criterion. Results It was shown that the maximum values of the mineralizing capacity fall to 7–8 a.m. and 18–19p.m., which is due to the change in the rate of saliva secretion. The near-24-h dynamics of the saliva pH practically coincides with the dynamics of the Ca/P ratio; there are evident maxima at 9:00 am and 15–18p.m. The values of the Na/K ratio are out of phase with the Ca/P ratio. There is one maximum, corresponding to 3 am in the night, and one minimum at 12–13p.m., which is due to a decreased level of sodium and increased potassium concentration. Statistically valid differences between men and women in pH (p < 0.001), concentrations of inorganic phosphorus (p < 0.001), as well as Ca/P coefficient (p = 0.011) were identified. Conclusion The dynamics of the studied parameters during 24 h is characterized by pronounced intervals. [ABSTRACT FROM AUTHOR]

Biomineralization is a complicated process which involves multiple gene products inPinctada fucata. Here,Pinctada fucatamantle gene 2 (pfmg2) was characterized inP. fucata. The putative PFMG2 protein has a Calponin Homology (CH) domain and an EF hand that can bind calcium. PFMG2 shares homology with transgelin in other species. Multi-tissue reverse transcriptase polymerase chain reaction (RT-PCR) indicates thatpfmg2mRNA is expressed ubiquitously, but its expression is high in the mantle tissue ofP. fucata. Furthermore,in situhybridization shows thatpfmg2localized at the edge of the mantle. Our results suggest that PFMG2 plays an important role in the shell mineralization process in pearl oyster. The analysis and the functional characterization of PFMG2 inP. fucatawill provide new insight into the mineralization process. [ABSTRACT FROM AUTHOR]

Negatively charged macromolecules play a starring role in Ca 2 + saturation at interfaces: they act as organized points for biomineral growth in nature. However, the role positively charged interfaces play in biomineralization remains unknown. Therefore, we decided to use a cationic Langmuir-Blodgett (LB) film composed of dioctadecyldimethylammonium bromide (DOMA) and type-I collagen in the presence of CaCl 2 solutions to guide CaCO 3 growth on titanium surfaces. Ca 2 + was able to interact with DOMA monolayers, leading to impressive cation excess at the film surface, as evidenced by the increased positive zeta potential of the LB films. Additionally, molecular dynamics simulations showed that Ca 2 + co-ions were able to accumulate on the positively charged LB interface, especially because configurations like R-N(+)-counterion-Ca 2 + existed therein. Counterion-mediated Ca 2 + accumulation on the surface was mainly driven by Cl − ions, which were much closer to Ca 2 + ions than Br − ions. Ca 2 + excess on the surface was sufficient to grow continuous and particulate CaCO 3 films on titanium surfaces. In addition, collagen presence induced changes in CaCO 3 film morphology and organization. Finally, we were able to confirm that positively charged organic interfaces can act as templates for biomineral growth because counterion-mediated Ca 2 + accumulation on these surfaces can drive subsequent crystal growth. This study provides insight into biomineralization templated by positively charged organic matrixes and into the design of bioinspired coatings for metallic surfaces. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the efficacy of demineralized dentin matrix (DDM) fixed with recombinant human bone morphogenetic protein-2 (rhBMP-2) through an experimental and a clinical study Unilateral upper second and third premolars of eight beagles were extracted. A mucoperiosteal flap was elevated around the extraction socket, and a bone defect was made using a surgical drill. Each DDM was fixed with rhBMP-2, and autogenous bone was grafted at the bone defect area with a collagenous membrane. The beagles were euthanized at two, four, eight, and 12 weeks after receiving the bone graft. Block specimens involving grafted bone and surrounding natural bone were extracted. A total of 23 patients who received bone grafts using human DDM fixed with rhBMP-2 (AutoBT BMP) with implant placements (36 implants; maxilla: 14, mandible: 22) were selected. The implant stability, marginal bone loss, and clinical outcome were evaluated. Three trephine cores were harvested fourmonths after bone grafting, and histologic examination was performed. In the histological evaluation performed four weeks after the bone graft, autogenous bone showed 52% new bone formation and DDM fixed with rhBMP-2 showed 33% new bone formation. Twelve weeks after the bone graft, autogenous bone showed 75% new bone formation and DDM fixed with rhBMP-2 showed 48% new bone formation. In the clinical study, favorable osseointegration was obtained in 35 out of 36 implant sites (one case of osseointegration failure). In all cases, severe complications were not observed. Histomorphometrically, new bone formation was observed in 14.98% of the cases. The residual DDM particles were 6.22%. AutoBT BMP provides good osteoinductive and osteoconductive potential and clinical efficacy. [ABSTRACT FROM AUTHOR]

The synthesis of crystals through biomineralization is a process of protection and support preserved in animals, protists, moneras, plants and fungi. The genome of every species has evolved to preserve and/or modify the formation of one or another type of crystal, which may be of the organic or inorganic type. The most common inorganic crystals identified in organisms include calcium carbonate (CaCO 3 ), calcium phosphate (CaP), calcium oxalate (CaOx), magnetite or greigite, and sulfides of cadmium (CdS), mercury (HgS) and lead (PbS). Organic crystals are of the protein or ice type. The formation of both types of crystals requires biomolecules such as proteins. This paper reviews the proteins involved in the synthesis of different crystals in distinct biological systems, in order to understand how each organism has adapted its genome to preserve essential mechanisms such as biomineralization, which has enabled them to survive in a changing environment for millions of years. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate heavy metals and selected minerals contents in filets of pikeperch ( Sander lucioperca), carp ( Cyprinus carpio) and flathead grey mullet ( Mugil cephalus), the major fish species produced in Sidi-Salem reservoir; the largest Tunisian freshwater ecosystem. Concentrations of Ca, Mg, Fe, Zn, Cd, Pb and Hg were determined by inductively coupled plasma-optical emission spectrometry, while concentrations of Na and P were determined by flame photometry and spectrophotometry, respectively. Results concerning heavy metals are considered quantitatively reliable for Hg and Cd but must be taken with precautions concerning Pb levels as the LOD (limit of detection) of the analytical process was higher than acceptable limit. They showed greater accumulations of both Hg and Cd in filets of pikeperch than in filets of carp and mullet, but none of the values exceeded the normative maximum levels (0.500 and 0.050 mg kg w.w., respectively). Considering provisional intakes, target hazard quotient and hazard index, estimated for a fish portion per week, consumption of any of the species did not appear to be potentially hazardous for the health as they were far below threshold values. A fish portion would provide substantial amounts (>15% of daily requirements) in essential mineral nutrients (P, Mg and Fe) and thus should be considered an interesting contribution to a healthy diet. It is strongly advocated to authorities including freshwater fish in the official national annual control survey of contaminants in fishery products, which in addition to guaranteeing security of consumers, would also allow diversifying valorisation opportunities and thus increase the economic value of this fish production. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) is an excellent biomaterial for bone repair and regeneration. The biological functions of HAp particles, such as biomineralization, cell adhesion, and cell proliferation, can be enhanced when their size is reduced to the nanoscale. In this work, HAp nanoparticles were synthesized by the hydrothermal technique with addition of cetyltrimethylammonium bromide (CTAB). These particles were also characterized, and their size controlled by modifying the CTAB concentration and hydrothermal duration. The results show that most HAp nanoparticles were rod-like in shape, exhibiting the most uniform and smallest size (mean diameter and length of 39 nm and 125 nm, respectively) at optimal conditions of 0.64 g CTAB and hydrothermal duration of 12 h. Moreover, good biomineralization capability of the HAp nanorods was confirmed through in␣vitro tests in simulated body fluid. A bone-like mineral layer of synthesized HAp nanorods formed rapidly after 7 days. This study shows that highly bioactive HAp nanorods can be easily prepared by the hydrothermal method, being a potential nanomaterial for bone regeneration. [ABSTRACT FROM AUTHOR]

Moonmilk is a karstic speleothem mainly composed of fine calcium carbonate crystals (CaCO3) with different textures ranging from pasty to hard, in which the contribution of biotic rock-building processes is presumed to involve indigenous microorganisms. The realmicrobial input in the genesis of moonmilk is difficult to assess leading to controversial hypotheses explaining the origins and the mechanisms (biotic vs. abiotic) involved. In this work, we undertook a comprehensive approach in order to assess the potential role of filamentous bacteria, particularly a collection of moonmilk-originating Streptomyces, in the genesis of this speleothem. Scanning electron microscopy (SEM) confirmed that indigenous filamentous bacteria could indeed participate in moonmilk development by serving as nucleation sites for CaCO3 deposition. The metabolic activities involved in CaCO3 transformation were furthermore assessed in vitro among the collection of moonmilk Streptomyces, which revealed that peptides/amino acids ammonification, and to a lesser extend ureolysis, could be privileged metabolic pathways participating in carbonate precipitation by increasing the pH of the bacterial environment. Additionally, in silico search for the genes involved in biomineralization processes including ureolysis, dissimilatory nitrate reduction to ammonia, active calcium ion transport, and reversible hydration of CO2 allowed to identify genetic predispositions for carbonate precipitation in Streptomyces. Finally, their biomineralization abilities were confirmed by environmental SEM, which allowed to visualize the formation of abundant mineral deposits under laboratory conditions. Overall, our study provides novel evidences that filamentous Actinobacteria could be key protagonists in the genesis of moonmilk through a wide spectrum of biomineralization processes. [ABSTRACT FROM AUTHOR]

Klotho is predominantly expressed in the kidney and reported to have antioxidant and antifibrotic properties. Soluble Klotho ( sKl), the circulating protein cleaved from membrane-bound Klotho, is reduced significantly with kidney disease and inversely associated with mortality. sKl has not been thoroughly evaluated prospectively after kidney transplantation. Incident kidney transplant recipients ( KTRs) were prospectively evaluated pretransplantation, 1, 12 and 52 weeks post-transplantation. Basic biochemistry, sKl and intact FGF23 were measured. Within-subject comparisons were evaluated using repeat-measure anova or Friedman's analysis. Effects of immunosuppression and biochemical parameters on sKl and FGF-23 over time were analysed using mixed-effects modelling. Median serum creatinine ( sCr) at 1 week was 116 (92-142) μmol/l, and at 52 weeks, all 29 KTRs had a functioning graft with median sCr of 111 (97-131) μmol/l. Compared with baseline, sKl was increased at 52 weeks following an initial decline at 1 week ( P < 0.005 and P < 0.01, respectively), while FGF23 was considerably reduced at 52 weeks ( P < 0.001). In a mixed-effects model, an increased sKl was not associated with reduction in immunosuppression or evaluated biochemical parameters. Modest increase in sKl is observed one-year postkidney transplantation with excellent early graft function suggesting factors beyond renal capacity may influence circulating sKl. FGF23 normalization was observed. Longer term evaluation in transplantation, specifically addressing the effects of immunosuppression, is required to understand the pathophysiology of the sKl/ FGF23 axis and potential for modification. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate Nd:YAG and CO2 laser effects in the prevention of demineralization in deeper layers of enamel via successive acid challenge cycles. Background data: Lasers are promising in the prevention of enamel demineralization around the orthodontic brackets; however, there are very few studies that evaluate if the effects of treatment could be extended after successive acid challenge cycles due to permanent enamel structural alterations. Materials and methods: Human enamel samples were divided into five groups ( n = 12): G1-application of 1.23% acidulated fluoride phosphate gel (AFP, control); G2-Nd:YAG laser irradiation (0.6 W, 84.9 J/cm2, 10 Hz, 110 μs, contact mode); G3-Nd:YAG laser irradiation associated with AFP; G4-CO2 laser irradiation (0.5 W, 28.6 J/cm2, 50 Hz, 5 μs, and 10 mm focal distance); and G5-CO2 laser irradiation associated with AFP. The samples were submitted to successive acid challenge cycles. Quantitative light-induced fluorescence and scanning electron microscopy were used to assess enamel demineralization. The data were statistically compared (α = 5%). Results: G1: 50.87 ± 4.57; G2: 47.72 ± 2.87; G3: 50.96 ± 4.01; G4: 28.21 ± 2.19; and G5: 30.13 ± 6.38. The CO2 laser groups had significantly lower mineral losses than those observed in all other groups after successive acid challenge cycles. Conclusions: Only the CO2 laser (10.6 μm) irradiation prevents enamel demineralization around the orthodontic brackets even after exposure to successive acid challenges. The CO2 laser at 10.6 μm showed a deeper effect in enamel regarding caries prevention. [ABSTRACT FROM AUTHOR]

The management of post-transplantation bone disease is a complex problem that remains under-appreciated in clinical practice. In these patients, preexisting metabolic bone disorder is further impacted by the use of immunosuppressive medications (glucocorticoids and calcineurin-inhibitors), variable post-transplantation renal allograft function and post-transplantation diabetes mellitus. The treatment of post-transplantation bone loss should begin pre-transplantation. All patients active on transplant waiting lists should be screened for bone disease. Patients should also be encouraged to take preventative measures against osteoporosis such as regular weight-bearing exercise, smoking cessation and reducing alcohol consumption. Biochemical abnormalities of disordered mineral metabolism should be corrected prior to transplantationwherever possible, and because these abnormalities commonly persist, post transplant hypophosphatemia, persistent hyperparathyroidism and low vitamin D levels should be regularlymonitored and treated. Bone loss is greatest in the first 6-12 months post-transplantation, during which period any intervention is likely to be of greatest benefit. There is strong evidence that bisphosphonates prevent post-transplantation bone loss; however, data are lacking that this clearly extends to a reduction in fracture incidence. Denosumab is a potential alternative to vitamin D receptor agonists and bisphosphonates in reducing post-transplantation bone loss; however, further studies are needed to demonstrate its safety in patients with a significantly reduced estimated glomerular filtration rate. Clinical judgement remains the cornerstone of this complex clinical problem, providing a strong rationale for the formation of combined endocrinology and nephrology clinics to treat patients with Chronic Kidney Disease-Mineral and Bone Disorder, before and after transplantation. [ABSTRACT FROM AUTHOR]

In recent years, scientists have developed various biomaterials to remineralize human teeth to treat dentine hypersensitivity. Poly(amido amine) (PAMAM) dendrimers have become a research focus in this field. It has been demonstrated that PAMAM is able to create precipitates both on the surface of and within the dentinal tubules, however, there is little information about its effect on reducing dentine permeability in vitro. This study aimed to evaluate the in vitro effectiveness and stability of the fourth generation amine-terminated PAMAM on dentinal tubule occlusion, especially on dentine permeability. Sodium fluoride (NaF), which has been widely used as a desensitizing agent, is regarded as positive control. Demineralized sensitive dentine samples were coated with PAMAM or sodium fluoride solutions and soaked in artificial saliva (AS) at 37 °C for different periods. Four weeks later, samples in each group were then equally split into two subgroups for testing using a brushing challenge and an acid challenge. Dentine permeability of each specimen was measured before and after each challenge using a fluid filtration system. Dentine morphology and surface deposits were characterized by scanning electron microscope (SEM) and analyzed with Image-Pro Plus software. Data were evaluated through multifactorial ANOVA with repeated measures and pair-wise comparisons at a level of 5%. The results showed that PAMAM and NaF significantly reduced dentine permeability to 25.1% and 20.7%. Both of them created precipitates on dentine surfaces after AS immersion for 28 days. PAMAM-induced biomineralization not only on dentine surfaces, but also deeper in dentinal tubules, significantly reduced dentine permeability. Moreover, PAMAM-induced biomineralization elicited excellent stable occlusion effects after acid challenge. In conclusion, PAMAM demonstrated a strong ability to resist acid and showed great potential to be used in the treatment of dentine hypersensitivity in future. [ABSTRACT FROM AUTHOR]

X-ray structures of homopolymeric L-ferritin obtained by freezing protein crystals at increasing exposure times to a ferrous solution showed the progressive formation of a triiron cluster on the inner cage surface of each subunit. After 60 min exposure, a fully assembled (μ3-oxo)Tris[(μ2-peroxo)(μ2-glutamato-κO:κO')](glutamato- κO)(diaquo)triiron(III) anionic cluster appears in human L-ferritin. Glu60, Glu61, and Glu64 provide the anchoring of the cluster to the protein cage. Glu57 shuttles incoming iron ions toward the cluster.We observed a similar metallocluster in horse spleen L-ferritin, indicating that it represents a common feature of mammalian L-ferritins. The structures suggest a mechanism for iron mineral formation at the protein interface. The functional significance of the observed patch of carboxylate side chains and resulting metallocluster for biomineralization emerges from the lower iron oxidation rate measured in the E60AE61AE64A variant of human L-ferritin, leading to the proposal that the observed metallocluster corresponds to the suggested, but yet unobserved, nucleation site of L-ferritin. [ABSTRACT FROM AUTHOR]

Although most adult bone mass is acquired before adolescence, only a few studies have assessed bone turnover markers in children. Thus, the utility of bone markers to evaluate and predict bone mineral accrual in children is unclear. The present study assessed the association between serum bone markers at 11 years of age and subsequent changes in bone gain. Information on bone minerals and bone markers at baseline and at the 3-year follow-up were obtained from 121 children who registered as fifth-grade students in 2010, in Hamamatsu, Japan. Whole-body bone mineral content (WBBMC) and whole-body bone mineral density (WBBMD) were measured using dual-energy X-ray absorptiometry. Boys showed significant (P < 0.05) positive relationships between intact osteocalcin at baseline and WBBMC at follow-up (β = 0.24), between tartrate-resistant acid phosphatase isoenzyme 5b (TRAP5b) and WBBMC (β = 0.34), and between TRAP5b and WBBMD (β = 0.34), after adjusting for potential confounding factors. In girls, adjusted means of 3-year gain in both WBBMC and WBBMD significantly increased from the lowest to highest quartiles of type 1 collagen cross-linked C-terminal telopeptide. In boys, adjusted means of 3-year gain in both WBBMC and WBBMD significantly increased from the lowest to highest quartiles of TRAP5b. Children with a high concentration of bone turnover markers tended to exhibit substantial accrual of bone minerals. These results suggest that serum levels of circulating biomarkers at age 11 predict subsequent bone mineral accrual. [ABSTRACT FROM AUTHOR]