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Calcium Absorption (calcium + absorption)
Kinds of Calcium Absorption Selected AbstractsCalcium Absorption from Commonly Consumed Vegetables in Healthy Thai WomenJOURNAL OF FOOD SCIENCE, Issue 9 2008S. Charoenkiatkul ABSTRACT:, The absorbability of calcium from ivy gourd, a green leafy vegetable (Coccinia grandix Voigt.) and winged bean young pods (Psophocarpus tetragonolobus [L] DC) were measured in 19 healthy adult women aged 20 to 45 y, in a 3-way, randomized-order, crossover design with an average calcium load of 100 mg and milk as the referent. The test meals were extrinsically labeled with 44Ca and given with rice as breakfast after an overnight fast. Absorption of calcium was determined on a blood sample drawn 5 h after ingestion of the test meal. Fractional calcium absorption (X± SD) was 0.391 ± 0.128 from winged beans, 0.476 ± 0.109 from ivy gourd, and 0.552 ± 0.119 from milk. The difference in fractional calcium absorption for these 2 vegetables was significant (P < 0.05) and the fractional calcium absorption from these 2 vegetables were both significantly lower than from milk. The difference was partly accounted for by the phytate, oxalate, and dietary fiber content of the vegetables. However, calcium bioavailability of these 2 vegetables, commonly consumed among Thais, was relatively good compared to milk (71% to 86% of milk) and could be generally recommended to the public as calcium sources other than milk and Brassica vegetables. [source] Percent true calcium absorption, mineral metabolism, and bone mass in children with arthritis: Effect of supplementation with vitamin D3 and calcium,,ARTHRITIS & RHEUMATISM, Issue 10 2008Laura S. Hillman Objective To assess whether percent true calcium absorption (,) is normal and whether supplementation with placebo, vitamin D3 (2,000 IU/day), calcium (1,000 mg/day), or vitamin D3 plus calcium improves ,, mineral metabolism, or bone mass accrual in children with arthritis. Methods Eighteen children received all 4 treatments, each for 6 months, in 4 different, randomly assigned orders. Changes in levels of 25-hydroxyvitamin D (25[OH]D), 1,25-dihydroxyvitamin D (1,25[OH]2D), parathyroid hormone, bone turnover markers, and minerals and in bone mineral content were measured. Calcium absorption was determined with a dual stable isotope method using 48Ca administered intravenously and 46Ca administered orally, and measuring 48Ca, 46Ca, and 42Ca in a 24-hour urine specimen by high-resolution inductively coupled plasma mass spectroscopy. Wilcoxon's signed rank test was used both to identify significant change over the treatment period with a given regimen and to compare change with an experimental treatment versus change with placebo. Results Percent true calcium absorption was in the lower-normal range and did not differ by treatment (mean ± SD 28.3 ± 20.2% with placebo, 26.1 ± 12.1% with calcium, 19.2 ± 11.7% with vitamin D3, and 27.1 ± 16.5% with vitamin D3 plus calcium). With vitamin D3 and vitamin D3 plus calcium treatment, 25(OH)D levels were increased and 1,25(OH)2D levels were maintained. Serum calcium levels were increased only with vitamin D3 and vitamin D3 plus calcium treatment. Levels of bone turnover markers and increases in bone mineral content did not differ by treatment. Conclusion The findings of this study indicate that percent true calcium absorption is low-normal in children with arthritis. Vitamin D3 at 2,000 IU/day increases serum 25(OH)D and calcium levels but does not improve bone mass accretion. Calcium at 1,000 mg/day also failed to improve bone mass. [source] Increasing Dietary Protein Requirements in Elderly People for Optimal Muscle and Bone HealthJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2009Erin Gaffney-Stomberg MS Osteoporosis and sarcopenia are degenerative diseases frequently associated with aging. The loss of bone and muscle results in significant morbidity, so preventing or attenuating osteoporosis and sarcopenia is an important public health goal. Dietary protein is crucial for development of bone and muscle, and recent evidence suggests that increasing dietary protein above the current Recommended Dietary Allowance (RDA) may help maintain bone and muscle mass in older individuals. Several epidemiological and clinical studies point to a salutary effect of protein intakes above the current RDA (0.8 g/kg per day) for adults aged 19 and older. There is evidence that the anabolic response of muscle to dietary protein is attenuated in elderly people, and as a result, the amount of protein needed to achieve anabolism is greater. Dietary protein also increases circulating insulin-like growth factor, which has anabolic effects on muscle and bone. Furthermore, increasing dietary protein increases calcium absorption, which could be anabolic for bone. Available evidence supports a beneficial effect of short-term protein intakes up to 1.6 to 1.8 g/kg per day, although long-term studies are needed to show safety and efficacy. Future studies should employ functional measures indicative of protein adequacy, as well as measures of muscle protein synthesis and maintenance of muscle and bone tissue, to determine the optimal level of dietary protein. Given the available data, increasing the RDA for older individuals to 1.0 to 1.2 g/kg per day would maintain normal calcium metabolism and nitrogen balance without affecting renal function and may represent a compromise while longer-term protein supplement trials are pending. J Am Geriatr Soc 57:1073,1079, 2009. [source] Vitamin D receptor amounts across different segments of the gastrointestinal tract in Brown Swiss and Holstein Frisean cows of different ageJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3 2008A. Liesegang Summary During different stages of lactation, different requirements of calcium have to be met depending on the milk amount. Vitamin D receptors (VDR) regulate calcium homeostasis by increasing the entry of Ca into blood from bone stores and dietary sources. The purpose of this study was to investigate if age and breed of cows influence VDR amounts across different segments of the gastrointestinal tract. Thirty-six cows were used (18 brown swiss, 18 holstein friesan, both > 5.5 years or < 4.5 years). Tissue specimens of the intestines were collected from the cows. Formaldehyde-fixed and microwave-treated paraffin sections were used for VDR immunohistochemistry employing a biotinylated monoclonal rat antibody and streptavidin peroxidase technique. The results showed that nuclei and cytoplasm of enterocytes stained positively for VDRs. Strongest immunoreactions were observed in intermediate and basal glandular cells. No significant differences were observed between the different groups. Vitamin D receptors immunoreactivities were prominent in duodenal mucosa, lower in jejunum and in colon, decreased further in ileum and were lowest in caecum. Decreases in number of positively marked cells and staining intensities resulted in reduced immunoreactions. The results of this study indicate that VDR are highly expressed at the site of maximal intestinal calcium absorption. No significant influence of age and breed was observed. The animals used were not in a negative Ca balance. The cows were all in the stage of late or mid lactation. During these periods, the Ca requirements are low and the diets are high in Ca concentration; and the animals are adapted to these circumstances. Passive absorption in adult animals seems to dominate when Ca intake is adequate or high. The active absorption may play a considerably more significant role during the peripartal period, when Ca homeostatic mechanisms are challenged because of tremendous Ca demand at the initiation of lactation. [source] Faecal bacterial profile, nitrogen excretion and mineral absorption in healthy dogs fed supplemental oligofructoseJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2002A. C. Beynen Summary In a cross-over trial, five healthy dogs were fed a dry food without or with 1% (w/w) oligofructose to assess any oligofructose-induced effects on the faecal bacterial profile, nitrogen excretion and mineral absorption. The diets were given for a period of 3 weeks. Oligofructose feeding significantly raised the number of Bifidobacteria, Streptococci and Clostridia in faeces. The numbers of faecal anaerobic and aerobic bacteria were raised after ingestion of oligofructose. The faecal pH was unchanged. There was no effect of oligofructose feeding on the route of nitrogen excretion which was associated with a lack of effect on faecal ammonium and urinary urea excretion. It is suggested that the absence or presence of an effect of oligofructose on urinary and faecal nitrogen excretion depends on the background composition of the diet, in particular the content of non-digestible, fermentable carbohydrates. In the diets used, the content of non-digestible, fermentable carbohydrates was not measured. Both apparent magnesium and calcium absorption were significantly raised by oligofructose feeding, but phosphorus absorption was unaffected. The data presented may contribute to the qualification of the use of oligofructose in dog foods. [source] Therapy of Osteoporosis With Calcium and Vitamin D,JOURNAL OF BONE AND MINERAL RESEARCH, Issue S2 2007Bess Dawson-Hughes MD Abstract Inadequate intakes of vitamin D and calcium lead to reduced calcium absorption, higher bone remodeling rates, and increased bone loss. Vitamin D insufficiency has also been linked to reduced muscle function and increased risk of falling. The mechanisms for the performance and muscle effects are not well understood. Administering vitamin D to those with inadequate vitamin D status has been shown to lower fracture rates in some trials but not in others. The purpose of this presentation is (1) to examine how calcium and vitamin D work in concert, (2) to consider key evidence that increasing vitamin D intake will affect risk of falls and fractures, and (3) to estimate the 25-hydroxyvitamin D [25(OH)D] level needed to achieve maximum fracture protection. [source] Calcium Channel TRPV6 Expression in Human Duodenum: Different Relationships to the Vitamin D System and Aging in Men and Women,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2006FRCP, Julian RF Walters MA Abstract Intestinal absorption of calcium affects bone mineralization and varies greatly. In human duodenum, expression of the calcium channel TRPV6 was directly related to blood 1,25-dihydroxyvitamin D in men, but effects of age with lower median vitamin D receptor levels were more significant in women. Introduction: The TRPV6 calcium channel/transporter is implicated in animal studies of intestinal calcium absorption, but in humans, its role and relationship to differences in mineral metabolism is unclear. We aimed to characterize TRPV6 expression in human intestine including defining relationships to the vitamin D endocrine system. Materials and Methods: TRPV6 transcript expression was determined in endoscopic mucosal biopsies obtained from normal duodenum. Expression was compared with that in ileum and with in situ hybridization in archival tissues and related to sequence variants in genomic DNA. TRPV6 expression was related in 33 subjects to other transcripts involved in calcium absorption including the vitamin D receptor (VDR) and to blood vitamin D metabolites including 1,25-dihydroxyvitamin D [1,25(OH)2D]. Results: TRPV6 transcripts were readily detected in duodenum but not in ileum. Expression was highest in villous epithelial cells. Sequence variants in the coding and upstream regions of the gene did not affect TRPV6 expression. The relationship between duodenal TRPV6 expression and 1,25(OH)2D differed in men and women. In men, linear regression showed a strong association with 1,25(OH)2D (r = 0.87, p < 0.01), which was unaffected by age. In women, there was no significant overall relationship with 1,25(OH)2D, but there was a significant decrease with age (r = ,0.69, p < 0.001). Individual expression of TRPV6 and VDR was significantly correlated. The group of older women (>50) had lower median levels of both TRPV6 and VDR transcripts than younger women (p < 0.001 and 0.02, respectively). Conclusions: Duodenal TRPV6 expression is vitamin D dependent in men, but not in older women, where expression of TRPV6 and VDR are both reduced. These findings can explain, at least in part, the lower fractional calcium absorption seen in older postmenopausal women. [source] Intestinal Calcium Transporter Genes Are Upregulated by Estrogens and the Reproductive Cycle Through Vitamin D Receptor-Independent Mechanisms,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2003SJ Van Cromphaut Abstract 1,,25(OH)2 -vitamin D strongly regulates the expression of the epithelial calcium channel CaT1. CaT1 expression is reduced in ERKO, mice and induced by estrogen treatment, pregnancy, or lactation in VDR WT and KO mice. Estrogens and vitamin D are thus independent potent regulators of the expression of this calcium influx mechanism, which is involved in active intestinal calcium absorption. Introduction: Active duodenal calcium absorption consists of three major steps: calcium influx into, transfer through, and extrusion out of the enterocyte. These steps are carried out by the calcium transport protein 1 (CaT1), calbindin-D9K, and the plasma membrane calcium ATPase (PMCA1b), respectively. We investigated whether estrogens or hormonal changes during the female reproductive cycle influence the expression of these genes, and if so, whether these effects are vitamin D-vitamin D receptor (VDR) dependent. Materials and Methods: We evaluated duodenal expression patterns in estrogen receptor (ER), and -, knockout (KO) mice, as well as in ovariectomized, estrogen-treated, pregnant, and lactating VDR wild-type (WT) and VDR KO mice. Results: Expression of calcium transporter genes was not altered in ERKO, mice. CaT1 mRNA expression was reduced by 55% in ERKO, mice, while the two other calcium transporter genes were not affected. Ovariectomy caused no change in duodenal expression pattern of VDR WT and KO mice, whereas treatment with a pharmacologic dose of estrogens induced CaT1 mRNA expression in VDR WT (4-fold) and KO (8-fold) mice. Pregnancy enhanced CaT1 expression equally in VDR WT and KO mice (12-fold). Calbindin-D9K and PMCA1b expression increased to a lesser extent and solely in pregnant VDR WT animals. In lactating VDR WT and KO mice, CaT1 mRNA expression increased 13 times, which was associated with a smaller increase in calbindin-D9K protein content and PMCA1b mRNA expression. Conclusions: Estrogens or hormonal changes during pregnancy or lactation have distinct, vitamin D-independent effects at the genomic level on active duodenal calcium absorption mechanisms, mainly through a major upregulation of the calcium influx channel CaT1. The estrogen effects seem to be mediated solely by ER,. [source] Calcium Absorption from Commonly Consumed Vegetables in Healthy Thai WomenJOURNAL OF FOOD SCIENCE, Issue 9 2008S. Charoenkiatkul ABSTRACT:, The absorbability of calcium from ivy gourd, a green leafy vegetable (Coccinia grandix Voigt.) and winged bean young pods (Psophocarpus tetragonolobus [L] DC) were measured in 19 healthy adult women aged 20 to 45 y, in a 3-way, randomized-order, crossover design with an average calcium load of 100 mg and milk as the referent. The test meals were extrinsically labeled with 44Ca and given with rice as breakfast after an overnight fast. Absorption of calcium was determined on a blood sample drawn 5 h after ingestion of the test meal. Fractional calcium absorption (X± SD) was 0.391 ± 0.128 from winged beans, 0.476 ± 0.109 from ivy gourd, and 0.552 ± 0.119 from milk. The difference in fractional calcium absorption for these 2 vegetables was significant (P < 0.05) and the fractional calcium absorption from these 2 vegetables were both significantly lower than from milk. The difference was partly accounted for by the phytate, oxalate, and dietary fiber content of the vegetables. However, calcium bioavailability of these 2 vegetables, commonly consumed among Thais, was relatively good compared to milk (71% to 86% of milk) and could be generally recommended to the public as calcium sources other than milk and Brassica vegetables. [source] Effect of Soluble Soybean Protein Hydrolysate-Calcium Complexes on Calcium Uptake by Caco-2 CellsJOURNAL OF FOOD SCIENCE, Issue 7 2008Y. Lv ABSTRACT:, Soybean protein hydrolysates (SPHs) bind with calcium, forming soluble SPH-calcium complexes via the carboxyl groups of glutamic and aspartic acid residues. However, their effect on calcium uptake is still unclear. In this study, Caco-2 cells were used to estimate the effect of SPH-calcium complexes with different molecular weights on calcium uptake in vitro. The changes in intracellular calcium ion concentration were measured by Fura-2 loading and expressed in fluorescence intensity. SPH-calcium complexes could promote calcium uptake. Improved fluorescence intensity was significantly different in SPH-calcium complexes (10 to 30 kDa), SPH-calcium complexes (3 to 10 kDa), and SPH-calcium complexes (1 to 3 kDa). The maximum levels of relative fluorescence intensity (18.3) occurred with SPH-calcium complexes (10 to 30 kDa). The effect of SPH-calcium complexes (10 to 30 kDa) on Ca2+ increase was determined to be concentration dependent in the range of 0.5 to 4 mg/mL. Our results indicate that soybean protein itself might be responsible for promoting calcium absorption. [source] A Soybean Cultivar Lacking Lipoxygenase 2 and 3 Has Similar Calcium Bioavailability to a Commercial Variety Despite Higher Calcium Absorption InhibitorsJOURNAL OF FOOD SCIENCE, Issue 3 2008H.S.D. Martino ABSTRACT:, The aim of this study was to evaluate calcium bioavailability of a new soybean variety without 2 lipoxygenases with better taste and flavor than a commercial variety containing all 3 isozymes. Using the femur 45Ca uptake method, calcium absorption from a new Brazilian variety, UFV-116, was compared to a common Brazilian variety, OCEPAR 19. Male Sprague,Dawley growing rats weighing 150 to 170 g (10/group) received test meals of whole fat soy flour prepared from UFV-116 or OCEPAR-19 seeds labeled with 10 ,Ci of 45Ca. Femurs were removed after 48 h for determination of 45Ca uptake. Calcium fractional absorption was equivalent between the 2 varieties. The higher oxalate:calcium molar ratio and the higher content of oxalate and phytate (P < 0.05) found in the UFV-116 variety did not affect calcium absorption. Therefore, the new variety is a comparable source of high bioavailable calcium. [source] Vitamin D receptor distribution in intestines of domesticated sheep Ovis ammon f. ariesJOURNAL OF MORPHOLOGY, Issue 2 2008Katharina Riner Abstract The biologically active form of vitamin D, i.e., 1,25-dihydroxycholecalciferol or calcitriol, plays an important role in bone metabolism and calcium homeostasis, which is often disturbed at the onset of lactation in high milk-yielding domestic ruminants. Gene transcription is modulated via vitamin D receptors, but nongenomic effects of vitamin D via membrane receptors have also been described. In the intestines, vitamin D promotes calcium absorption via vitamin D receptors. Vitamin D receptors are of clinical relevance, but have not been systematically assessed within all segments of the intestine in any species. Thus, we present for the first time an immunohistochemical study of the distribution patterns of the vitamin D receptor protein in sheep, which may be the basis for present and future investigations on mineral homeostasis in domestic ruminants. Tissue probes of the intestines were collected from five lambs and five nonlactating and nonpregnant dams, fixed in formalin, embedded in paraffin, and used for the assessment of vitamin D receptor protein. Nuclear vitamin D receptor immunoreaction was scored semiquantitatively and exhibited a segment-specific distribution pattern. Goblet cells always were devoid of any vitamin D receptor immunoreaction. Surface epithelial cells and enterocytes of the crypt openings generally demonstrated only a weak immunoreaction. Basally and/or intermediately located crypt epithelial cells exhibited stronger immunoreactions in duodenum, jejunum, and colon descendens. This basal/intermediate to superficial gradient was most pronounced in the duodenum and less evident in jejunum and colon descendens and not observed in ileum and cecum. There were no age-dependent variations in vitamin D receptor protein expression. Results demonstrate that intestinal vitamin D receptor distribution patterns are segment-specific and strongest immunoreactions correlate with highest intestinal calcium absorptive activities, as reported in literature. Strong expression of vitamin D receptors within the lower half of crypts also suggests a role for calcitriol in epithelial differentiation and cellular homeostasis. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source] Lactulose as a food ingredientJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2009Agustín Olano Abstract Lactulose is a synthetic ketose disaccharide that can be obtained from lactose by different methods of synthesis. Chemical methods are based on the isomerization of lactose in the presence of basic catalysts and enzymatic methods using lactose as a galactose donor and fructose as an acceptor. The prebiotic properties of lactulose have been known for more than 50 years and numerous studies have confirmed several health benefits of lactulose as a food ingredient, including selective stimulation of intestinal flora, laxative effect and improvement of calcium absorption. Its use in fermented milk manufacture may reduce the incubation period and favour the growth of bifidobacteria. The synthesis of lactulose-derived oligosaccharides may provide a new group of prebiotics with properties complementary to those of native lactulose. Copyright © 2009 Society of Chemical Industry [source] Fermentation of soybean by Rhizopus promotes the calcium absorption ratio in ratsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2008Nakamichi Watanabe Abstract BACKGROUND: Soy foods are generally considered to be an unfavourable source of calcium because soybean is rich in phytate, which retards the absorption of calcium. The objective of this study was to assess the effect of dietary fermented soybean, such as tempeh, on calcium absorption in rats. The rats were grouped into three dietary groups and fed the experimental diets for 4 weeks. Soybean, conventional tempeh prepared by aerobic fermentation with Rhizopus (tempeh), and novel tempeh prepared by aerobic and successive anaerobic fermentations (anaerobic tempeh) were used as the protein sources of the experimental diets. RESULTS: The order of the calcium absorption ratio for the 3 days before the end of the test period was as follows: tempeh group > anaerobic tempeh group > soybean group. CONCLUSION: The calcium absorption ratio of the tempeh group in particular was significantly higher than those of the other two groups. The high calcium absorption ratio of the tempeh group might be caused by both low phytate contents and peptides that are produced during the fermentation of soybean by Rhizopus. Copyright © 2008 Society of Chemical Industry [source] In vitro bioavailability of calcium and iron from selected green leafy vegetables,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2006Sheetal Gupta Abstract The objective of the present investigation was to analyze the relative influence of oxalic acid, phytic acid, tannin and dietary fiber on in vitro availability of iron and calcium from green leafy vegetables (GLV). Thirteen GLV were selected and analyzed for iron, calcium, oxalic acid, phytic acid, tannin and dietary fiber contents using standard methods. The bioavailability of calcium and iron in the GLV was estimated by equilibrium dialysis. Oxalic acid content was less than 1 g kg,1 in four greens and ranged between 1.22 to 11.98 g kg,1 in the remaining. Dietary fiber ranged from 19.5 to 113.7 g kg,1. Tannin content ranged between 0.6138 and 2.1159 g kg,1 with the exception of two GLV that had 0.1332 and 14.8619 g kg,1. Four GLV were found to have approximately 40% bioavailable iron, while the others were in the range of 6,30%. In vitro available calcium was less than or equal to 25% in eight GLV and between 34% and 52% in five GLV. Multiple regression analysis revealed that these factors together accounted for 53% (r2 = 0.53) and 45% (r2 = 0.45) inhibition of iron and calcium absorption, respectively. These findings infer that calcium and iron availability is influenced by the constituents present in the GLV. Copyright © 2006 Society of Chemical Industry [source] Changes in calcium absorption and subsequent tissue distribution induced by Maillard reaction products: in vitro and in vivo assays,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2006Cristina Delgado-Andrade Abstract The effects of Maillard reaction products (MRP) from glucose,lysine and glucose,methionine on calcium bioavailability were studied by in vivo (rats) and in vitro (Caco-2 cells) assays. Equimolar glucose/lysine and glucose/methionine mixtures (40% moisture) were heated (150 °C, 30 min) to prepare samples (GL30 and GM30, respectively). For 21 days, rats were fed a control diet (control group) or diets containing separately 3% of the heated mixtures (GL30 and GM30 groups, respectively). In the last week a calcium balance was performed, after which the animals were sacrificed and some organs and serum were removed to analyze calcium levels. A second balance was carried out throughout the experimental period to calculate global calcium retention (retained calcium during the entire 21 days). Unheated and heated samples were used for calcium transport experiments in Caco-2 cells. Food intake and final body weight were lower in the GM30 group. Calcium fecal excretion decreased and digestibility increased in this group. Accordingly, increased calcium transport in Caco-2 cells was found in the presence of the GM30 sample, when compared with the unheated sample. However, global calcium retention tended to decrease in the GM30 group, mainly owing to the lower food intake. Bone calcium concentrations decreased in the animals fed the MRP diets. The possible long-term effects of MRP intake on calcium digestibility and bone calcium should be taken into account to avoid related diseases. Copyright © 2005 Society of Chemical Industry [source] Review article: prebiotics in the gastrointestinal tractALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2006S. MACFARLANE Summary Background Prebiotics are short-chain carbohydrates that alter the composition, or metabolism, of the gut microbiota in a beneficial manner. It is therefore expected that prebiotics will improve health in a way similar to probiotics, whilst at the same time being cheaper, and carrying less risk and being easier to incorporate into the diet than probiotics. Aim To review published evidence for prebiotic effects on gut function and human health. Methods We searched the Science Citation Index with the terms prebiotic, microbiota, gut bacteria, large intestine, mucosa, bowel habit, constipation, diarrhoea, inflammatory bowel disease, Crohn's disease, ulcerative colitis, pouchitis, calcium and cancer, focussing principally on studies in humans and reports in the English language. Search of the Cochrane Library did not identify any clinical study or meta-analysis on this topic. Results Three prebiotics, oligofructose, galacto-oligosaccharides and lactulose, clearly alter the balance of the large bowel microbiota by increasing bifidobacteria and Lactobacillus numbers. These carbohydrates are fermented and give rise to short-chain fatty acid and intestinal gas; however, effects on bowel habit are relatively small. Randomized-controlled trials of their effect in a clinical context are few, although animal studies show anti-inflammatory effects in inflammatory bowel disease, while calcium absorption is increased. Conclusions It is still early days for prebiotics, but they offer the potential to modify the gut microbial balance in such a way as to bring direct health benefits cheaply and safely. [source] Hereditary hypophosphatemias: New genes in the bone,kidney axis (Review Article)NEPHROLOGY, Issue 4 2007ARMANDO L NEGRI SUMMARY: Hypophosphatemia due to isolated renal phosphate wasting is a genetically heterogeneous disease. Two new genes linked to two different forms of hereditary hypophosphatemias have recently been described. Autosomal recessive form of hypophosphatemic rickets was mapped to chromosome 4q21 and identified homozygous mutations in dentin matrix protein 1 (DMP1) gene, which encodes a non-collagenous bone matrix protein. Intact plasma levels of the phosphaturic protein FGF23 (fibroblast growth factor 23) were clearly elevated in some of the affected individuals, providing a possible explanation for the phosphaturia and inappropriately normal 1,25(OH)2D levels, and suggesting that DMP1 may regulate FGF23 expression. Hereditary hypophosphatemic rickets with hypercalciuria is another rare disorder of autosomal recessive inheritance. Affected individuals present with hypercalciuria due to increased serum 1,25-dihydroxyvitamin D levels and increased intestinal calcium absorption. The disease was mapped to a 1.6 Mbp region on chromosome 9q34, which contains SLC34A3, the gene encoding the renal sodium-phosphate cotransporter NaPi-IIc. This was the first demonstration that NaPi-IIc has a key role in the regulation of phosphate homeostasis. Thus, DMP1 and NaPi-IIc add two new members to the bone,kidney axis proposed since it was discovered that the first phosphatonin, FGF23, was of osteoblastic/osteocyte origin. This provides a mechanism for the skeleton to communicate with the kidney to coordinate the mineralization of extracelular matrix and the renal handling of phosphate. [source] Building Bones in Babies: Can and Should We Exceed the Human Milk-Fed Infant's Rate of Bone Calcium Accretion?NUTRITION REVIEWS, Issue 11 2006Steven A. Abrams MD Increasing calcium absorption and bone calcium accretion to levels above those achieved by human milk-fed, full-term infants is possible with infant formulas. However, no data support such a goal or suggest that it is beneficial to short- or long-term bone health. Small differences in the bioavailability of calcium between infant formulas are unlikely to have long-term consequences. Long-term studies of the effects of infant feeding type on ultimate bone mass are needed. For now, the vitamin-replete breast-fed infant's rate of calcium accretion during the first year of life should be the standard targeted for infant formulas [source] Latest news and product developmentsPRESCRIBER, Issue 3 2007Article first published online: 14 MAR 200 PPIs and hip fracture Treatment with a PPI may increase the risk of hip fracture, with longer use associated with higher risk according to a study in UK patients (J Am Med Assoc 2006;297:2947-53). The case control study compared use of PPIs by 13 556 patients with hip fracture and 135 386 controls in the UK General Practice Research Database. Use of a PPI for more than one year was associated with an increase of 44 per cent in the odds of hip fracture. The risk was higher for longer- term use (59 per cent after four years) and at higher doses (more than doubled with long-term high doses). The mechanism for this possible effect may be impaired calcium absorption associated with hypochlorhydria and reduced bone resorption. CHD NSF Statin prescribing has increased by 30 per cent every year since the publication of the Coronary Heart Disease NSF, the Department of Health says. The estimated number of lives saved attributable to statins had risen to 9700 in 2005. The proportion of patients with acute MI who were given thrombolysis within 30 minutes of admission has increased to 83 per cent. Flu jabs cut pneumonia deaths A US study suggests that flu vaccine protects against death during the flu season in patients admitted with community-acquired pneumonia (Arch Intern Med 2007;167:53-9). Nineteen per cent of patients admitted with pneumonia during the winters of 1999-2003 were known to have been vaccinated against flu. Their risk of death during their hospital stay was 70 per cent lower than that of nonvaccinated individuals. After adjustment for antipneumococcal vaccination and comorbidity, the odds of death were still 39 per cent lower. Model to predict admissions The King's Fund, together with New York University and Health Dialog, has published a model that predicts the risk of emergency hospital admission (see www.kingsfund.org.uk). The model is intended for use by PCTs and draws on data from secondary and primary care to define clinical profiles, allowing patients whose condition is deteriorating to be identified before they need admission. Problem drinking The National Treatment Agency for Substance Misuse (NTA), a special authority within the NHS, has published a critical appraisal of the evidence for various treatments for alcohol problems (www.nta.nhs.uk). The 212-page document estimates that over seven million hazardous or harmful drinkers may benefit from brief interventions by any health workers, and over one million dependent drinkers may benefit from specialist intervention. It concludes that cognitive behavioural approaches to specialist treatment are most effective and that treatment probably accounts for about one-third of improvements made in problem drinking. of patients remained on the same treatment after one year, falling to half at two years and about 40 per cent at three years. Treatment was more frequently stopped for lack of efficacy than for adverse effects. Stopping anti-TNFs Discontinuation of treatment with anti-TNF agents is more common in clinical practice than in clinical trial populations, a French study has found (J Rheumatol 2006;33:2372-5). The retrospective analysis of a single centre's experience of treating 770 patients with etanercept (Enbrel), infliximab (Remicade) or adalimumab (Humira) found that fewer than two-thirds of patients remained on the same treatment after one year, falling to half at two years and about 40 per cent at three years. Treatment was more frequently stopped for lack of efficacy than for adverse effects. There were no statistically significant differences between the three agents but there was a trend for infliximab to be least well tolerated. Generic statin savings The Department of Health has estimated that prescribing simvastatin and pravastatin generically would save £85 million per year. Its analysis of the ,Better care, better value' indicators (see www.productivity.nhs.uk) shows that statin prescribing has increased by 150 per cent in the past five years, with costs totalling £600 million in 2005. The Department says that if every PCT prescribed pravastatin and simvastatin by generic name in only 69 per cent of cases ,the level achieved by the top quarter of trusts ,the savings would be over £85 million a year. Herceptin reporting Press reports of a two-year trial of trastuzumab (Herceptin) were generally accurate in reporting its effectiveness but few reported an increased risk of adverse effects, according to the NHS National Library for Health (www.library.nhs.uk). The Herceptin Adjuvant (HERA) trial (Lancet 2007;369:29-36) found that, after an average follow-up of two years, 3 per cent of women treated with trastuzumab died compared with 5 per cent of controls; estimated three-year survival rates were 92.4 and 89.7 per cent respectively. All four press articles reported these findings accurately, but only two mentioned the increased risk of adverse effects. Updated guidance on CDs The Department of Health has published updated guidance on the strengthened governance requirements for managing controlled drugs, taking into account new regulations that came into force on 1 January (seewww.dh.gov.uk/asset Root/04/14/16/67/04141667.pdf). Statin adherence lowers MI mortality Patients with acute myocar- dial infarction (MI) who take their statins as prescribed are significantly more likely to survive for two to three years than those with low adherence (J Am Med Assoc 2007;297: 177-86). The four-year observational study of 31 455 patients with acute MI found that, compared with those who had taken at least 80 per cent of prescribed daily doses, the risk of death in those with less than 40 per cent adherence was 25 per cent greater over 2.4 years. For individuals with intermediate adherence (40-79 per cent), the risk was 12 per cent greater. Both differences were statistically significant after adjustment for potential confounding factors. The authors believe their finding is explained by differences in adherence rather than healthier behaviour because the excess risk of low adherence was less marked with beta-blockers and not significant for calcium-channel blockers. Improving community medicines management Mental health trusts need to improve medicines management by their community teams and improve information sharing with GPs, the Healthcare Commission has found (www.healthcare commission.org.uk). Its national report revealed limited evidence of pharmacist involvement in community mental health teams, even though 90 per cent of patients were cared for in the community. Only 11 per cent of assertive outreach patients had the tests necessary to ensure safe use of their medicines. Medication reviews found that 46 per cent of patients in mental health trusts and 12 per cent of those in acute trusts were not taking their medication appropriately. The Commission also reported that acute trusts received a complete drug history from GPs for fewer than half of audited patients when they were admitted to hospital, and only 30 per cent of PCTs reported that GPs received adequate information on patients' medicines on discharge. Copyright © 2007 Wiley Interface Ltd [source] Percent true calcium absorption, mineral metabolism, and bone mass in children with arthritis: Effect of supplementation with vitamin D3 and calcium,,ARTHRITIS & RHEUMATISM, Issue 10 2008Laura S. Hillman Objective To assess whether percent true calcium absorption (,) is normal and whether supplementation with placebo, vitamin D3 (2,000 IU/day), calcium (1,000 mg/day), or vitamin D3 plus calcium improves ,, mineral metabolism, or bone mass accrual in children with arthritis. Methods Eighteen children received all 4 treatments, each for 6 months, in 4 different, randomly assigned orders. Changes in levels of 25-hydroxyvitamin D (25[OH]D), 1,25-dihydroxyvitamin D (1,25[OH]2D), parathyroid hormone, bone turnover markers, and minerals and in bone mineral content were measured. Calcium absorption was determined with a dual stable isotope method using 48Ca administered intravenously and 46Ca administered orally, and measuring 48Ca, 46Ca, and 42Ca in a 24-hour urine specimen by high-resolution inductively coupled plasma mass spectroscopy. Wilcoxon's signed rank test was used both to identify significant change over the treatment period with a given regimen and to compare change with an experimental treatment versus change with placebo. Results Percent true calcium absorption was in the lower-normal range and did not differ by treatment (mean ± SD 28.3 ± 20.2% with placebo, 26.1 ± 12.1% with calcium, 19.2 ± 11.7% with vitamin D3, and 27.1 ± 16.5% with vitamin D3 plus calcium). With vitamin D3 and vitamin D3 plus calcium treatment, 25(OH)D levels were increased and 1,25(OH)2D levels were maintained. Serum calcium levels were increased only with vitamin D3 and vitamin D3 plus calcium treatment. Levels of bone turnover markers and increases in bone mineral content did not differ by treatment. Conclusion The findings of this study indicate that percent true calcium absorption is low-normal in children with arthritis. Vitamin D3 at 2,000 IU/day increases serum 25(OH)D and calcium levels but does not improve bone mass accretion. Calcium at 1,000 mg/day also failed to improve bone mass. [source] Effect of phytate-removal and deamidation of soybean proteins on calcium absorption in the in situ ratsBIOFACTORS, Issue 1-4 2004Hitomi Kumagai Abstract Soybean proteins were deamidated by cation-exchange resins after phytate, the inhibitor for calcium absorption from the small intestine, was removed in order to provide the enhancement function of calcium absorption to soybean proteins. About 92% of the phosphorus was removed from the soybean proteins by anion-exchange-resin treatment, indicating that most of the phytate was removed. About 70% of the acid amide was deamidated by cation-exchange-resin treatment, and phytate-removed and deamidated soybean proteins (PrDS) having high calcium binding properties were obtained. PrDS were hydrolyzed by digestive enzymes and their calcium-binding properties and the enhancement function of the calcium absorption from the small intestine of rats were examined. As a result, PrDS retained their high calcium binding properties even after hydrolysis by digestive enzymes. in situ experiments showed that PrDS and their hydrolysates enhanced the calcium absorption from the intestine. [source] | ||||||||||||||||