PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Calcification, Physiologic”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

[Bone/cement interface reactions following several years of implantation and consequences for its fixation].

Retrieved femora with fixed cemented hip arthroplasties were sectioned horizontally. Bone sections were prepared of the whole cross-sectional area to study the bone/cement-interface (bci) histologically and morphometrically. The interface between bone and cement mainly consists of a thin (< 25 microns) connective tissue layer. Demineralized zones were in parts found, this tendency seems to slightly increase in time. The bone newly formed at the bci is structured like thick trabecular bone or like dense cortical bone. A strong fixation seems possible even if a thin connective tissue layer exists, and a complete adaptation of the implant to the bone is not necessary, as the bone adapts as well.

Adaptation, Physiological↗
PubMed2000

Effects of low phytic acid corn on phosphorus utilization, performance, and bone mineralization in broiler chicks.

In vivo and in vitro experiments were conducted to determine whether P in a low-phytate corn (LPC) containing the lpa 1-1 allele is more available than P in a near-isogenic wild-type corn hybrid (NC). The LPC was analyzed to contain 0.18% nonphytate P and 0.26% total P (TP), whereas NC contained 0.05% nonphytate P and 0.25% TP. For these studies, nonphytate P was considered to be available P (AP). In the in vivo study, 150 1-d-old male chicks were randomly assigned to five treatments (six pens of five chicks each) for 21 d. The dietary treatments included: A) a diet containing 60% NC, 0.2% AP, and 0.8% Ca; B) a diet containing 60% LPC, 0.28% AP, and 0.8% Ca; C) an NC diet similar to Diet A, but with KH2PO4 added to increase the AP to 0.28% to match the AP in Diet B; D) an LPC diet containing 0.45% AP and 1% Ca; and E) an NC diet supplemented with KH2PO4 to provide 0.45% AP and 1% Ca. Diets A, B, and C were semipurified diets, with corn being the sole source of phytate. The only differences between Diets A and B were the source of corn and the amount of AP present in the diets. The levels of AP in these diets were deficient in order to measure the animal response to the different levels of AP. Diets D and E were typical corn-soybean meal diets, and were formulated to contain an optimal level of AP. Performance and bone ash were similar (P > 0.05) in chicks fed Diets B and C and in chicks fed Diets D and E. Chicks fed LPC diets (B and D) retained more P (P < 0.05) than chicks fed NC diets (C and E). Chicks fed Diet B had significantly higher (P < 0.05) Ca retention compared with chicks fed Diet A. An in vitro digestion procedure that simulated the physiological conditions of the gastrointestinal tract of broilers was used to determine P release from LPC and NC. Results showed that 65% (1,420 mg/kg) of the TP in LPC was released, compared with 23% (543 mg/kg) from NC. Results of these experiments indicate that the P in LPC is more available than the P in NC, and reducing the phytate content did not compromise the nutritional value of LPC. The increased P retention in chicks fed LPC suggests that substituting LPC for NC leads to a reduction in manure P. Also, the in vitro procedure accurately predicted differences in in vivo P availability between the two corns.

Animal Nutritional Physiological Phenomena↗
PubMed2003

Efficacy of a phytase derived from Escherichia coli and expressed in yeast on phosphorus utilization and bone mineralization in turkey poults.

A slope-response bioassay was conducted with male turkey poults to determine the sparing effect of P, based on improvements in bone mineralization in turkey poults, from 10 to 21 d of age when diets were supplemented with a novel phytase. Reference diets for calculation of the sparing effect of P contained 0.47, 0.55, 0.70, and 0.79% nonphytate phosphorus (NPP). Diets with varying dosages of a swine, Escherichia coli-derived AppA2 phytase (ECP) expressed in Pichia pastoris yeast (0, 250, 500, 750, and 1,000 U/kg) were added to the 0.47% NPP diet and improvements in bone mineralization determined the sparing effect of P supplied from ECP. Two additional reference diets were included that contained 500 U/kg from one of two commercial phytases (PA and PB) derived from Aspergillus and Peniophora. At 500 U/kg diet the ECP spared an additional 0.22% NPP (if calculated from tibia ash %), 0.18% NPP (if calculated from toe ash %), 0.24% NPP (if calculated from mg tibia ash), or 0.21% NPP (if calculated from mg toe ash). Phosphorus retention results validate bioassay results, in that 500 U ECP/kg resulted in 68.2% P being retained (0.49% of diet P retained) as compared with only 58.9% P being retained from the unsupplemented control diet (0.421% of diet P retained; P < 0.05).

6-Phytase↗
PubMed2004

Evaluation of microbial phytase in broiler diets.

Two trials were conducted to evaluate the efficacy of a new microbial phytase (Phyzyme XP) for broiler chicks. Trial 1 used 192 8-d-old male broilers in a 14-d trial to assess growth and nutrient utilization. Dietary treatments (221.9 g/kg CP) included a positive control [5.0 g/kg nonphytate P (NPP)], negative control (1.2 g/kg NPP), and negative control plus 500 or 1,000 phytase units/kg of diet. Phytase addition increased weight gain, feed intake, feed efficiency, and tibia and toe ash (linear, P < 0.01) with tibia ash also responding quadratically (P < 0.05). Apparent ileal digestibility of P (linear and quadratic, P < 0.05), tryptophan, and valine (linear, P < 0.05) also increased. Linear and quadratic responses were observed for retention of DM, nitrogen, P, and several amino acids (P < 0.05) with added phytase. Trial 2 utilized 576 1-d-old male broilers over a 42-d period to evaluate growth performance. Diets were formulated for starter (222.7 g/kg CP) and grower (201.5 g/kg CP) phases and included a positive control (starter and grower, 5.0 and 3.8 g/kg NPP, respectively); negative control (starter and grower, 2.4 and 1.8 g/kg NPP, respectively); negative control plus 500, 750, or 1,000 phytase units/kg; and negative control plus 500 phytase units/kg of Natuphos phytase. Phytase increased weight gain and feed intake (starter, grower, overall) as well as feed efficiency during the starter period (linear, P < 0.05). Feed intake was also improved during the grower period and overall (quadratic, P < 0.05). Tibia and toe ash of birds fed for the first 21 d increased (linear, P < 0.05) with tibia ash also increasing quadratically (P < 0.05). Overall, tibia and toe ash were improved due to phytase addition (linear and quadratic, P < 0.05). In conclusion, this microbial phytase, derived from Escherichia coli and expressed in Schizosaccaromyces pombe, elicited improved growth performance, bone mineralization, and P utilization in broiler chicks.

6-Phytase↗
PubMed2004

Effects of copper source on phosphorus retention in broiler chicks and laying hens.

Copper sulfate is often added to broiler and laying hen diets at prophylactic dosages due to its antimicrobial and growth promoting effects despite reduced P digestibility, whereas P use from other Cu sources is unknown. Therefore, male broiler chicks were fed diets containing 0 or 250 ppm Cu from Cu sulfate (Cu SUL), Cu citrate (Cu CIT), Cu lysinate (Cu LYS), or CuCl from 9 to 22 d of age (8 cages/diet, 6 birds/cage) to determine the effect of each Cu source on performance characteristics, bone mineralization, and P retention. Body weight gain was not different among treatments (P > 0.05). Supplementation with 250 ppm Cu from Cu LYS resulted in chicks having greater toe and tibia ash weights as compared with chicks fed Cu SUL (P < or = 0.05) but was not significantly different from those of birds fed Cu CL, Cu CIT, and 0 ppm Cu diets. Supplementation with Cu LYS resulted in birds with greater toe ash percentage as compared with birds fed Cu CIT, Cu SUL, and the 0 ppm Cu diets (P < or = 0.05) but was not significantly different than those of birds fed the CuCl diet. Birds fed the Cu LYS diet had greater tibia ash percentage as compared with birds fed Cu SUL and 0 ppm Cu diets (P < or = 0.05) but were not significantly different than birds fed the Cu CL or Cu CIT diet. Supplementation with 250 ppm Cu SUL or Cu CIT reduced apparent P retention by 0.029 and 0.053 percentage-units of the diet, respectively (P < or = 0.05) as compared with the 0 ppm diet; whereas the apparent P retention when 250 ppm Cu LYS or Cu CL was fed was not different from the 0 ppm Cu diet (P > 0.05). Feeding of different Cu sources in a subsequent experiment had no influence on P retention in laying hens (P > 0.05). In conclusion, supplementation with 250 ppm Cu from Cu CIT or Cu SUL resulted in decreased apparent P retention. Supplementation with 250 ppm Cu CL or Cu LYS, however, improved apparent P retentions as compared with Cu CIT or Cu SUL.

Aging↗
PubMed2004

The effects of copper on the efficacy of phytase, growth, and phosphorus retention in broiler chicks.

Copper is often added to broiler diets at prophylactic concentrations as an antimicrobial despite purported chelation with and reduced utilization of phytin phosphorus. Therefore, male chicks were fed 0, 62.5, 125, 250, or 375 ppm Cu from Cu sulfate in combination with 600 phytase units (FTU)/kg phytase from 9 to 22 d of age (6 cages/diet, 8 birds/cage). Nonphytate phosphorus (NPP) and Ca were formulated to 0.2 and 0.7% of the diet, respectively. Three additional control diets were formulated to contain 0.27, 0.34, and 0.40% NPP, each with 0.7% Ca. Birds fed increasing concentrations of Cu with 600 FTU phytase/kg had linear reductions in performance characteristics (P < or = 0.05). Birds fed increasing concentrations of Cu with 600 FTU phytase/kg had linear increases in toe ash percentage (P < or = 0.027), but tibia ash percentage was not affected (P > 0.05). Birds fed increasing Cu concentrations with 600 FTU phytase/kg had linear reductions in apparent P retention as a percentage of total P (P < or = 0.0005). Supplementation with increasing concentrations of Cu to a diet containing 600 FTU phytase/kg resulted in decreases in 21 d BW, BW gain, feed consumption, feed conversion, tibia and toe ash weights, and apparent P retention as a percentage of total P. In this experiment, Cu supplementation did not reduce the efficacy of phytase (i.e., improvement in apparent P retention with phytase supplementation) but did decrease apparent P retention, BW gain, feed consumption, feed conversion, and tibia ash and toe ash weights.

6-Phytase↗
PubMed1964

CALCIFICATION OF DECIDUOUS TEETH IN RHESUS MONKEYS.

The rhesus monkey probably has the same sequence of calcification of deciduous teeth as man: central incisor, first molar, lateral incisor, cuspid, and second molar. Initial calcification of the deciduous molar cusps is somewhat similar to that of man.

Animals↗