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PubMed1988

Effects of pH on mineral-phytate, protein-mineral-phytate, and mineral-fiber interactions. Possible consequences of atrophic gastritis on mineral bioavailability from high-fiber foods.

A common gastrointestinal tract problem afflicting the elderly is that of reduced hydrochloric acid secretion by the stomach mucosa. This results in raised stomach pH values and in reduced activity of the digestive enzyme pepsin, which is responsible for the hydrolysis of dietary proteins to polypeptides. The effects of these alterations of the stomach on the digestion of high-fiber foods and resultant mineral bioavailability have not been defined. This paper reviews the effects of pH on the mineral-phytate, protein-mineral-phytate, and mineral-fiber interactions that would be present in high-fiber foods. Possible consequences of raised stomach pH values on mineral bioavailability from high-fiber foods are discussed.

Biological Availability↗
PubMed1996

Mineral anisotropy in mineralized tissues is similar among species and mineral growth occurs independently of collagen orientation in rats: results from acoustic velocity measurements.

It has been reported that the mineral crystals in long bones have their c-axis aligned with the bone axis, presumably because collagen fibrils in bone also align with the bone axis. However, the predominant collagen orientation in bone often does not appear to be aligned with the mineral crystals, especially in rat primary bone. We hypothesized that mineral orientation in bone is not necessarily related to collagen orientation. An acoustic microscope was used to measure elastic constants of mineralized tissues from rat, cow, monkey, and human bone, and mineralized turkey leg tendon (MTLT). Measurements were made before and after demineralization with 10% ethylenediaminetetraacetic acid (EDTA) or decollagenization with 7% sodium hypochlorite. The elastic anisotropy ratio (AR) was defined as the ratio of the elastic coefficient in the longitudinal direction to the elastic coefficient in the transverse direction. Anisotropy ratios of mineralized tissues were not affected by formalin fixation or plastic embedding. An evaluation of tissues from the different species showed that the AR after decollagenization was not significantly different (p > 0.4, analysis of variance) among the groups, while AR after demineralization varied from 1.04 (rat bone) to 1.51 (MTLT). There was no correlation between AR after demineralization and AR after decollagenization (r = 0.13, p = 0.5). This showed that the elastic anisotropy of collagen is more variable than mineral anisotropy in bone and MTLT. Another experiment showed that mineralization of turkey leg tendon changes the elasticity of the collagen matrix, making it less anisotropic. A final, prospective experiment was performed in which tibiae of rats were subjected to mechanical loading for 16 weeks. After 12 days, new periosteal woven bone was observed on the tibiae and, after 16 weeks, this new bone was consolidated and mineralized. Mineral in the newly formed woven bone was virtually isotropic (AR = 1.07) after 12 days of loading, then became more anisotropic (AR = 1.52) after 16 weeks of mechanical loading, as the mineral density of the new bone increased. This increase in anisotropy of bone mineral occurred even though the collagen matrix was woven and had no measureable fibril orientation. We conclude that (1) collagen anisotropy and mineral anisotropy are not necessarily correlated in mineralized tissues, (2) mineralization can affect the collagen matrix elasticity of mineralized tissues, and (3) an organized mineral structure can form in the absence of an organized collagen matrix.

Acoustics↗
PubMed2000

Antioxidant vitamin and mineral supplements for age-related macular degeneration.

BACKGROUND: It has been proposed that antioxidants may prevent cellular damage in the retina by reacting with free radicals produced in the process of light absorption. OBJECTIVES: The objective of this review is to assess the effects of antioxidant vitamin and/or mineral supplementation on the progression of age-related macular degeneration. SEARCH STRATEGY: The Cochrane Eyes and Vision Group specialised registered, the Cochrane Controlled Trials Register - Central, MEDLINE, the Science Citation Index, and the reference lists of relevant articles were searched. Investigators of included studies were contacted. The most recent searches were performed in December 1999. SELECTION CRITERIA: All randomised trials comparing an antioxidant vitamin and/or mineral supplement (alone or in combination) to control in people with age-related macular degeneration were included. DATA COLLECTION AND ANALYSIS: The reviewer extracted data and assessed trial quality. Due to the small number of trials identified, and variable methods of collecting and presenting outcome data, no statistical summary measure was calculated. MAIN RESULTS: Four published, two unpublished and two ongoing trials were identified. Published trials to date have been small and results inconsistent. Adverse effects and quality of life for people with age-related macular degeneration have not been addressed. REVIEWER'S CONCLUSIONS: The question as to whether people with age-related macular degeneration should take antioxidant vitamin or mineral supplements to prevent progression of the disease has not been answered by research to date. The results of ongoing trials are awaited.

Antioxidants↗
PubMed2004

Effect of dietary trace mineral concentration and source (inorganic vs. chelated) on performance, mineral status, and fecal mineral excretion in pigs from weaning through finishing.

Two hundred and sixteen weanling gilts (6.65+/-0.08 kg) were used to determine the effects of decreasing supplemental concentrations of Zn, Cu, Fe, and Mn, and trace mineral source (inorganic vs. chelated) on growth performance, mineral status, and fecal mineral concentrations from weaning through development. The study was conducted over three trials with 72 pigs in each trial. Gilts were blocked by weight and randomly assigned to either 1) control, 2) reduced inorganic, or 3) reduced chelated trace minerals. The control diet was supplemented with 25, 150, 180, and 60 mg/kg of Cu, Zn, Fe, and Mn (in sulfate forms), respectively, during the nursery phase and 15, 100, 100, and 40 mg/kg of supplemental Cu, Zn, Fe, and Mn, respectively, during the growing and gilt-developer phases. Reduced inorganic and reduced chelated treatments were supplemented during all phases with 5, 25, 25, and 10 mg/kg of Cu, Zn, Fe, and Mn, respectively. The reduced chelated treatment supplied 50% of the supplemental Cu, Zn, Fe, and Mn in the form of metal proteinates, with the remainder from sulfate forms. Performance by control pigs did not differ from pigs fed the reduced trace mineral treatments during the nursery and grower-development periods. Gain:feed was lower (P < 0.05) for pigs fed the reduced inorganic compared with those fed the reduced chelated treatment during the nursery period. Trace mineral source did not affect performance during the growing or gilt-developer phase. Plasma Zn concentration and alkaline phosphatase activity were higher (P < 0.01) in control pigs than in those receiving reduced trace minerals during the nursery and growing phases. Plasma Cu concentration and ceruloplasmin activity were generally not affected by treatment. Hemoglobin concentrations were lower (P < 0.05) for the reduced inorganic compared with the reduced chelated treatment in the nursery phase. Fecal concentrations of Cu, Zn, and Mn were lower (P < 0.05) in pigs fed reduced trace minerals than in controls during all production phases. Fecal Zn concentration during the nursery and fecal Cu concentrations during the growing and gilt-developer phases were lower (P < 0.05) in pigs fed the reduced chelated compared with the reduced inorganic treatment. Results indicate that reducing the concentrations of Zn, Cu, Mn, and Fe typically supplemented to pig diets will greatly decrease fecal mineral excretion without negatively affecting pig performance from weaning through development.

Animal Feed↗
PubMed1985

Mineral homeostasis in very premature infants: serial evaluation of serum 25-hydroxyvitamin D, serum minerals, and bone mineralization.

This study was designed to evaluate the role of vitamin D sufficiency, as reflected in serum 25-hydroxyvitamin D (25-OHD) concentrations, on serum minerals and bone mineralization in very premature infants. Seventy-two infants (mean +/- SD gestation 30.1 +/- 2.5 weeks, mean +/- SD birth weight 1178 +/- 278 gm) were observed serially for the first 3 months of life. Mean serum calcium and phosphorus values, but not magnesium, remained low prior to 12 weeks. The percentage of infants with moderate to severe hypomineralization was 75% at 3 weeks, 55% at 6 weeks, 54% at 9 weeks, and 15% at twelve weeks. Low serum calcium and phosphorus values, high alkaline phosphatase activity, and moderate-severe hypomineralization were more frequent in infants weighing less than 1000 gm and in those with lower mineral intake. With a 400 IU vitamin D supplement, 45% of infants could maintain an initially normal serum 25-OHD concentration or increase low concentrations, whereas 55% had falling or persistently low (less than or equal to 15 ng/ml) 25-OHD concentrations. Birth weight and mineral intakes were comparable in these two groups, yet the group with the lower serum 25-OHD concentration had lower serum calcium and higher alkaline phosphatase values, and a higher percentage of moderate to severe hypomineralization. Regardless of birth weight, mineral intake, or 25-OHD concentration, increases in serum calcium and phosphorus values and in mineralization were seen at postconception term (12 weeks in most infants, nine weeks in those weighing 1250 to 1600 gm). At 12 weeks of age, but not before, serum 25-OHD concentration was directly correlated with serum calcium (r = 0.47, P less than 0.01) and serum phosphorus (r = 0.47, P less than 0.01) and inversely correlated with alkaline phosphatase values (r = -0.71, P less than 0.01). Mineral availability and 25-OHD sufficiency both appear to be important and to act synergistically, with neither totally compensating for the other.

Alkaline Phosphatase↗
PubMed1984

Mineral content of quail embryos cultured in mineral-rich and mineral-free conditions.

Japanese quail embryos were cultured in mineral rich (MR) using chickens egg shell and mineral-free (MF) using Saran Wrap cultures after 2.5 days of normal incubation. In the MR culture, 82% of embryos survived beyond 14.5 days of incubation and 3 embryos out of 93 (3%) hatched. In the MF culture, 80% survived beyond 9.5 days and 59% beyond 14.5 days. Mineral content (Ca, Mg, K, and Na) of the embryos and of the residual matter within the egg (remaining egg contents excluding the embryo, shell, and shell membrane) were analyzed at 7 to 15 days of incubation. Calcium content of the embryos increased gradually between 9 and 11 days and showed a rapid increase after 11 days in both normal incubation (control) and MR culture. Changes in mineral levels of the embryos plus residual matter within the egg were as follows. Calcium content of the controls increased gradually between 9 and 11 days and showed a rapid increase after 11 days. In MR cultures, Ca increased between 10 and 12 days and showed a rapid increase after 12 days. Magnesium content increased rapidly after 13 days in controls and showed a small increase after 13 days in MR cultures. Potassium and Na content remained constant in both controls and MR cultures. In MF cultures, content of the four minerals remained constant throughout the culture period. Mineral levels of Japanese quail and chicken eggs were compared before and after normal incubation. It was found that 81.5% of Ca and 30.8% of Mg assimilated by newly hatched quail chicks were derived from the egg shell during incubation and 84.2% of Ca and 23.5% of Mg in the chicken.

Animals↗
PubMed1990

[Hygienic evaluation of mineralizing lime substances for correction of mineral composition of low-mineral drinking water].

4 out of 6 mineralizing lime materials that were studied have been recommended for the practical application with the aim to correct the mineral composition of drinking low-mineralized water. The possibility to predict the biological properties of multicomponent mineralizing materials has been established on the basis of results of analysis of their chemical composition.

Calcium↗
PubMed2006

Survey of strontium in mineral waters sold in Japan: relations of strontium to other minerals and evaluation of mineral water as a possible dietary source of strontium.

The concentrations of strontium, calcium, and magnesium in 33 brands of natural mineral waters commercially available in Japan were determined by inductively coupled plasma-atomic emission spectrometry. The geometric mean values were 94.4 microg/L for strontium, 19.1 mg/L for calcium, and 2.82 mg/L for magnesium. Wide confidence intervals of 1.96-4539 microg/L for strontium, 0.865-421 mg/L for calcium, and 0.064-123 mg/L for magnesium were observed. The significant linear relationships among the three elements over a wide distribution range suggest that the synchronized variations of these elements are regulated by the natural ecosystem and not from accidental contamination from human activities or exceptionally high natural sources. Using the results of multiple linear regression analysis, the strontium concentration can be predicted by that of calcium with the appropriate power function. The results of this study suggest that mineral water can be an important nutritional source of strontium. As trace elements imbalance is often found in older patients with chronic renal failure, we propose that close attention of trace elements intake from trendy foods or beverages is necessary to prevent this hidden problem of a rapidly aging society.

Calcium↗
PubMed1997

Research bibliography: a union list of publications from Michigan's mineral springs, mineral wells, and mineral baths.

Although no more than a few dozen mineral wells and springs existed in Michigan at any one time, since their discovery over 125 years ago nearly two hundred firms have operated watering places for the suffering in this state. The publications produced by this industry were collectively quite numerous, but scarcely a hundred or so examples of this genre can be located today. On those rare occasions when materials of this nature can be found in out-of-print book stores or antiquarian dealers'catalogs, it is not uncommon for the asking price to approach $100 per piece. Now that this union list has revealed how scarce and valuable these publication are, persons and institutions possessing such items should take precautions to ensure the security of their holdings.

Baths↗
PubMed1997

Randomized trial of varying mineral intake on total body bone mineral accretion during the first year of life.

OBJECTIVE: The effect of varying mineral intakes on total body bone mass accretion during the first year of life in healthy full-term infants is unknown. The purpose of this study was to determine whether total body bone mass accretion during the first year of life was influenced by the calcium and phosphorus intake of an infant and whether early differences in bone accretion persist through 1 year of age. DESIGN: This prospective, randomized trial was conducted in two phases. In phase I, 67 infants were randomized within the first 2 weeks of life into either a low (439 mg of calcium per liter and 240 mg of phosphorus per liter) or moderate (510 mg of calcium per liter and 390 mg of phosphorus per liter) mineral-containing formula feeding group. An additional group of 34 human milk-fed (low mineral) infants also was enrolled. Phase II involved an additional randomization of all infants at 6 months of age into moderate-mineral formula (see above), high-mineral formula (1350 mg of calcium per liter and 900 mg of phosphorus per liter), or cow milk (1230 mg of calcium per liter and 960 mg of phosphorus per liter) feeding group. Anthropometric measurements, nutrient intake, and total body bone mineral content (BMC) by dual-energy x-ray absorptiometry were measured at 1, 3, 6, 9, and 12 months. RESULTS: During the first 6 months, the moderate-mineral group had a greater increase in weight (3.42 +/- 0.62 kg) compared with the human milk group (2.93 +/- 0.56 kg); the low-mineral group (3.19 +/- 0.62 kg) was intermediate. Bone mass accretion differed in a similar direction, with the moderate-mineral feeding group having a greater increase than the human milk group and the low-mineral group being intermediate of the two. Including weight, length, and bone area as covariates, both the low-mineral formula- and human milk-fed groups had similar BMC, which was lower than that of the moderate-mineral group at 3 and 6 months of age. Adjusted mean BMC values for the moderate-mineral formula-fed group compared with the low-mineral formula- and human milk-fed groups were 127.8 +/- 1.5 (SEM) g vs 119. 2 +/- 1.5 and 122.1 +/- 1.4 g, respectively, at 3 months of age and 168.7 +/- 2.5 g vs 157.6 +/- 2.5 and 158.7 +/- 2.4 g, respectively, at 6 months of age. The BMC at 6 months of age among the formula-fed infants was correlated with both average dietary phosphorus intake (r = .592) and average daily calcium intake (r = .620) during the first 6 months. The relationships between BMC and these minerals remained significant even after controlling for caloric intake. It was not possible to determine the independent effects of dietary calcium and phosphorus on BMC because of the strong correlation of these minerals with each other. Despite significant differences in both calcium and phosphorus intakes during the second 6 months of life, there were no differences in growth parameters or bone mass accretion. Means for BMC, adjusted for body weight, length, and bone area, were not significantly different among feeding groups at either 9 or 12 months of age. Adjusted means were 199 +/- 2 (SEM) and 237 +/- 3 g at 9 and 12 months of age for infants receiving moderate-mineral formula; 198 +/- 2 and 236 +/- 3 g at 9 and 12 months of age for infants receiving the high-mineral formulas and 202 +/- 5 and 233 +/- 5 g at 9 and 12 months of age for infants receiving cow milk. The gain in bone mass during the second 6 months differed by the first 6-month feeding group; mean changes in BMC between 6 and 12 months, adjusted for changes in weight, length, and bone area, were greater in human milk-fed infants than in either the low- or moderate-mineral-containing formula groups: 81 +/- 16 g in human milk-fed infants and 73 +/- 15 and 71 +/- 15 g in the low- and moderate-mineral formula groups, respectively. Infants fed whole cow milk during the second 6 months were excluded from this analysis because of the small number of infants completing the study. By 12 months of age t

Absorptiometry, Photon↗
PubMed1999

The long-term effect of early mineral, vitamin D, and breast milk intake on bone mineral status in 9- to 11-year-old children born prematurely.

BACKGROUND: Although the short-term benefits of mineral supplementation in preterm infants has been established, the long-term benefits are less clear. The purpose of the study was to evaluate effects of early-life mineral, vitamin D, and breast milk intake on bone mineral status in children 9 to 11 years of age who were born prematurely. METHODS: Seventy preterm infants born 1985 through 1987 were randomized into four groups: to receive a vitamin D dose of 500 or 1000 IU/day and calcium- and phosphorus-supplemented or unsupplemented breast milk. At 3 months of age, radial bone mineral content was determined by single-photon absorptiometry and vitamin D metabolites were assessed. At 9 to 11 years of age, the bone mineral status of the radius and lumbar spine was assessed using dual energy x-ray absorptiometry. RESULTS: At the age of 3 months, the preterm infants with diets supplemented with minerals had 36% higher bone mineral content than the preterm infants whose diet was not supplemented with minerals. At the age of 9 to 11 years, in contrast, bone mineral status was comparable among the groups, irrespective of different mineral supplementation during the neonatal period. Interestingly, the lumbar bone mineral apparent density was positively related to lactation in mineral-supplemented children. There was neither short-term nor long-term benefit to bone mineral status of a vitamin D dose of 1000 IU/day compared with 500 IU/day. CONCLUSIONS: The short-term benefit to bone mineral density in preterm infants of mineral supplementation of the early diet is obvious, but, in the long term, the effects seem to disappear. The results also imply that a relatively long period of breast-feeding may be needed to optimize long-term bone mineral acquisition in the lumbar spine.

Absorptiometry, Photon↗
PubMed2004

The mineral scoring technique and evaluation of indigenous browse species as natural mineral phytocentres for goats in African rangelands.

The utilization and evaluation of indigenous browse species as natural mineral phytocentres for goats was examined by the combined use of mineral concentrations, mineral scores, browse accessibility and abundance in the Ankole rangeland, Uganda. The species Grewia bicolor and Carissa edulis with > 140% mineral scores and > 70% accessibility were the most valuable mineral phytocentres and were the victims of overgrazing. Acacia albida and Acacia abyssinica with > 130% mineral scores but < 30% browse accessibility were valuable for the cut-and-carry feeding system. Species mineral scores at average and maximum dietary recommendations were < 60%, highlighting the mineral insufficiency of range browse for high-performance goats. Mineral supply potential was highest (35.0%) in the genus Acacia and lowest (5.3%) in Dichrostachsys. Browse accessibility was < 35%, in 69.2% of species. Acacia hockii was the most abundant species (24.5%) but had the lowest mineral score (17.7%). Browse species (90-100%) were deficient in Fe, Mn, Cu and Zn. The combined use of mineral concentrations and mineral scoring technique was superior to the use of mineral concentrations alone in defining mineral adequacy, deficiency and supply potential, making the mineral scoring technique a valuable tool in browse management.

Acacia↗
PubMed2001

Mineral supplementation of white wheat flour is necessary to maintain adequate mineral status and bone characteristics in rats.

This experiment was designed to compare the effect of ingestion of a wheat flours on mineral status and bone characteristics in rats. White flour was tested either without further mineral supplementation or with Mg, Fe, Zn and Cu supplementation. The flour diets were compared to a control purified diet. Four groups of 10 male Wistar rats each were fed one of the experimental diets for 6 wk and mineral status and tissue retention as well as bone characteristics were determined. As expected, mineral intake, except for calcium, was significantly lesser in rats fed the white flour diet than in the other groups. The rats fed the white flour diet had the lowest food intake, weight gain, fecal excretion and intestinal fermentation. The most important result was that Mg and Fe status were drastically lower in rats fed the white flour diet than in those fed whole flour or control diets. The status of these both elements were significantly improved by the mineral supplementation of white flour. There were no major significant differences between mineral-supplemented white flour and whole flour groups in mineral status. Furthermore, bone mineral densities (total, metaphyseal and diphyseal) were significantly lower in rats fed white flour diet compared to the other diet groups, while no significant difference was observed between the mineral-supplemented white flour, whole flour or control diet groups. In conclusion, the present work shows clearly the importance of mineral-supplementation of white wheat flour to sustain an adequate intake of minerals. Our results indicate also that the whole wheat flour did not negatively alter mineral bioavailability, in comparison to mineral supplemented white flour. Clinical studies are still needed to confirm these rat results in human.

Animal Feed↗
PubMed2005

Sodium bicarbonated mineral water decreases postprandial lipaemia in postmenopausal women compared to a low mineral water.

The role of bicarbonated mineral waters on lipid metabolism and lipoprotein concentrations in man has scarcely been investigated. The present study aimed to investigate whether drinking sodium bicarbonated mineral water affects postprandial cholesterol and triacylglycerol metabolism in postmenopausal women. In a three-way, randomised, crossover study, eighteen healthy postmenopausal women consumed two sodium bicarbonated mineral waters (bicarbonated mineral water 1 and bicarbonated mineral water 2) and a low mineral water (500 ml of each) with a standard fat-rich meal (4552 kJ; 75.3 g fat). The bicarbonated waters were rich in sodium and bicarbonate and bicarbonated mineral water 1 contained 5.7 times more fluoride than bicarbonated mineral water 2. Fasting blood samples and postprandial blood samples were taken at 30, 60, 120, 240, 360 and 420 min after the end of the meal consumption. Cholesterol and triacylglycerols were determined in serum and chylomicrons. A significant water consumption effect was observed in the total area under the curve (TAUC) of serum and chylomicron triacylglycerols (ANOVA, P=0.008 and P=0.027, respectively). TAUC of serum triacylglycerols for bicarbonated mineral water 2 was significantly lower compared to low mineral water (Bonferroni, P=0.039). Peak concentration of serum triacylglycerols showed a significant water effect (P=0.025). Changes in chylomicron cholesterol were not significantly affected by the type of water. Bicarbonated mineral waters 1 and 2 did not show any significant differences. Drinking sodium bicarbonate-rich mineral waters reduces postprandial lipaemia in healthy postmenopausal women compared to drinking a low mineral water.

Analysis of Variance↗
PubMed2006

Nature of phosphate substrate as a major determinant of mineral type formed in matrix vesicle-mediated in vitro mineralization: An FTIR imaging study.

Membrane-bound extracellular matrix vesicles play an important role in the de novo initiation and propagation of calcium-phosphate mineral formation in calcifying cartilage, bone, dentin, and in pathologic calcification. Characterization of the phase, composition, crystal size, and perfection provides valuable insight into the mechanism of the mineral deposition. In the present study, Fourier transform infrared imaging spectroscopy (FT-IRIS) was used to characterize the mineral phase generated during MV-mediated in vitro mineralization. FT-IRIS studies revealed that the mineral phase associated with MVs calcified in the presence of AMP and beta-GP was always found to be crystalline hydroxyapatite while with ATP only a small amount of immature mineral, most likely an amorphous or poorly crystalline hydroxyapatite, was observed. Low concentrations of pyrophosphate (PPi) (< or = 0.01 mM) showed apatitic mineral while high concentrations showed immature calcium pyrophosphate dihydrate (CPPD). The implications of these findings are that (a) hydrolysis of AMP or beta-GP, monophosphoester substrates of MV-5' AMPase (substrate: AMP) and TNAP (substrates: AMP, beta-GP), yields orthophosphate (Pi) which leads to the formation of mature crystalline, apatite mineral, while the hydrolysis of ATP, substrate for MV-TNAP or ATPase or NPP1, inhibits the formation of mature hydroxyapatite, and (b) pyrophosphate (PPi) has a bimodal effect on mineralization, i.e., at low PPi concentrations, alkaline phosphatase activity of matrix vesicles is able to hydrolyze PPi to orthophosphate and thus facilitates the formation of basic calcium phosphate mineral which subsequently transforms into apatitic mineral. We hypothesize that, at high PPi concentrations, PPi by itself or Pi released by partial PPi hydrolysis could act as inhibitors of alkaline phosphatase activity, thereby preventing complete hydrolysis of PPi to Pi, and thus resulting in the accumulation of calcium pyrophosphate dihydrate. Therefore, in order for physiological mineralization to proceed, a balance is required between levels of Pi and PPi.

Animals↗
PubMed1992

Mineral nutrition and bone mineralization in full-term infants.

Bone mineralization is an intricate and tightly regulated process. Calcium, magnesium and phosphorus are the main minerals and play a principal role in skeletal mineralization. The following conclusions can be derived from different clinical studies. The large differences in Ca/P ratio between different formulas and between formulas and human milk suggest that most healthy full-term infants can adjust to a wide range of Ca/P ratio in their diet. The differences in serum levels of mineral and of mineral-regulating hormones are rarely clinically significant and most probably reflect continued compensatory mechanisms activated in response to dietary differences to maintain these levels within clinically normal ranges. Thus in most cases, these compensatory mechanisms are sufficient to reverse both short-term and long-term consequences and to prevent clinical disease. In the case of neonatal tetany, the compensatory mechanisms are overwhelmed, resulting in clinical signs and disease. Vitamin D is known to play an essential role in bone mineralization. Our studies have shown significant differences in vitamin D status in breast-fed infants with and without vitamin D supplementation and in infants fed various "humanized" formulas, whether cow milk-based or soy protein-based. The major variables affecting bone mineralization are Ca/P ratio and mineral-regulating hormones. However, factors such as season, geography (i.e. sun exposure), race and sex may have a significant long-term influence on bone mineralization and mineral metabolism. Some biological differences such as differences in serum vitamin D metabolite level may directly effect Ca/P absorption and retention and thus bone mineralization and growth.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Density↗
PubMed2004

[Comparison of TGF-beta1 expression of lung cancer in Gejiu miners with that in non-miners in other regions].

OBJECTIVE: To investigate the different expression of transforming growth factor beta(1) (TGF-beta(1)) in lung cancer specimens of Gejiu miners, and non-miners in other regions. METHODS: Thirty specimens of Gejiu miners' lung cancer and 30 specimens of non-miners' were observed in this experiment. The expression of TGF-beta(1) protein and TGF-beta(1) mRNA were detected by the methods of immunohistochemistry and in situ hybridization. The results were quantitatively analyzed using image analysis system. RESULTS: The positive rate of TGF-beta(1) protein expression in Gejiu miners and non-miners was 75.39%and 44.78% respectively, and the positive rate of TGF-beta(1) mRNA was 63.96% and 34.07% respectively. There were significant differences between the two groups (P < 0.01). CONCLUSION: The expression of TGF-beta(1) in lung cancer of Gejiu miners was significantly higher than that of non-miners. The pathogenesis of lung cancer may be different between Gejiu miner and non-miners. High expression of TGF-beta(1) may be one of the reasons of high incidence of lung cancer in Gejiu miners.

Humans↗