Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The following investigation was undertaken to study the location in the dental plaque and calculus of certain enzyme activities and to compare the patterns obtained with those of the normal hard tissue formation. Supragingival and subgingival calculus attached to the root surfaces of 30 extracted teeth was studied. The root with its deposits was frozen rapidly in a mixture of hexane and solid CO2 (-75 degrees C). From the frozen block, sections were cut and incubated for histochemical demonstration of lactate dehydrogenase, alkaline phosphatase and acid phosphatase. The plaque seemed to be stratified with regard to enzyme activity. Three different layers could be identified. In the basal layer, approximately 100 microns thick, enzyme activity was low. Lactate dehydrogenase activity could be identified in some sections, but no phosphatase activity. In the middle layer lactate dehydrogenase, alkaline phosphatase and acid phosphatase activities were found in most of the sections. The superficial layer usually showed lactate dehydrogenase but not always acid or alkaline phosphatase activities. The results of the present investigation may suggest that the mineralization of the dental plaque is not only a passive mineralization of dead bacteria, but also an active process promoted by enzymes in the covering bacterial layers.
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PMID:An enzyme histochemical study of dental plaque and calculus. 696 68

Tissue culture techniques were used to study a number of factors and mechanisms which are important in the development and metabolism of bone tissue. As an example of an external factor influencing bone development, the importance of the composition of the gasphase which is in equilibrium with the fluid bathing osteoblasts and hypertrophic chondrocytes, was investigated in cultured metatarsal bone rudiments. In vivo, one expects the presence of an O2 gradient in the cartilaginous epiphyses of long bones: low O2 tension between the nonhypertrophic chondrocytes, high O2 tension in periosteum and hypertrophic zone, bordering the marrow cavity. The in vitro findings correlated with these expectations. High CO2 (5%) and high O2 (40%) tensions stimulated calcification; in air, calcification was severely inhibited. On the other hand, maturing chondrocytes were damaged by high O2 tensions. An important cellular mechanism in calcification is the intracellular accumulation of calcium (and phosphate) in osteoblasts and hypertrophic chondrocytes which can be demonstrated with the GBHA stain of Kashiwa [9]. The extracellular role of alkaline phosphatase (AP) present on the cell membranes of these cells was shown to be a less decisive factor in calcification. In the presence of AP inhibitor in a concentration high enough to inhibit AP activity to a large extent, calcification was shown to proceed normally. The effects of a number of hormones known to be important for the development and metabolism of bone tissue was studied using tissue culture (calvaria) as well as culture of different isolated bone cells. The parathyroid hormone (PTH) induced rise of the intracellular cAMP level was found to originate primarily from the osteoblasts not the osteoclasts. Isolated osteoblasts showed a high cAMP response after PTH addition. Cortisol was shown to inhibit PTH induced resorption but to potentiate PTH induced cAMP response in calvaria. Various PTH fragments (desamino 1-34, 2-34, 3-34) were shown to be active as stimulators of bone resorption (although they were less active in this respect than the intact molecule 1-84), but did not stimulate cAMP production in calvaria or isolated osteoblasts. The results obtained strengthened the hypothesis that cAMP is not the (only) mediator in PTH induced bone resorption.
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PMID:Regulatory mechanisms in the development of bone and cartilage: the use of tissue culture techniques in the study of the development of embryonic bone and cartilage: a perspective. 715 53

To investigate the mechanism of biological calcification in vitro, a model system consisting of an acrylamide gel block (1 x 3 x 3 mm) and fetal bovine serum was developed. Mineral deposition was induced in gel blocks which were immersed in 300 microliters of fetal bovine serum at 37 degrees C for 7 days in a CO2 incubator. X-ray diffraction indicated that the mineral was hydroxyapatite with low crystallinity. Effects of the concentration of acrylamide gel, the partial pressure of CO2 and matrix proteins within the gel on the mineral formation were investigated. In the gel concentration range of 10-60%, the largest amount of crystal grew in 40% acrylamide gel, where the serum protein did not penetrate. With an increase in the partial pressure of CO2 the Ca content in the gel block increased, reached the highest level at about 3.5% CO2 and then began to decrease. In 40% gel and at 5% CO2, the mineral formation was enhanced by phosvitin, phosphophoryn, demineralized dentin powder and alkaline phosphatase. Mineral deposition occurred around the collagen fibers immobilized in 40% acrylamide gel. These results indicate that 1) a putatively serum-derived inhibitor of calcification with high-molecular weight was prevented from penetrating into the 40% acrylamide gels, 2) immobilized polyanionic proteins and alkaline phosphatase were able to increase mineral deposition and 3) the partial pressure of CO2 greatly influenced the mineral deposition. It was concluded that this gel system is useful to investigate the mechanism of biological calcification in vitro.
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PMID:A new method for in vitro calcification using acrylamide gel and bovine serum. 755 52

Blood samples were taken and subjected to biochemical analysis in the crossbred cows of the Red-Pied, Black-Pied or Holstein-Friesian breed raised on a large farm under standard conditions, with the average annual milk yield of 4,300 kg milk, and divided into two groups--cows with afterbirth retention and without it; the samples were taken in the last period of pregnancy (since day 245), during parturition, and within the first 50 days post partum. In both groups, the values of acid-base balance and metabolic profile mostly ranged within the interval of reference values, nevertheless there were certain trends and differences in absolute values as well as in the dynamics of changes, but they did not always show a doubtless character and the same significance. The cows with afterbirth retention exhibited a trend of a more expressive decrease in partial pressure CO2, actual acid output and phosphorus level. Glucose level at the end of pregnancy was statistically significantly lower (P < 0.01), cholesterol level also decreased (P < 0.05). On the other hand, the cows with afterbirth retention had, at the end of pregnancy, statistically significantly higher concentrations of urea and creatinine (P < 0.05-0.01), a higher bilirubin level and enzyme activities of acid phosphatase, and particularly of aspartate aminotransferase and lactate dehydrogenase (P < 0.05-0.01). There were insignificant differences in the concentrations of total protein, calcium, magnesium and enzyme activity of alkaline phosphatase and gammaglutamyl transferase.
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PMID:[Metabolic profile in cows in the peripartum period with and without retained placenta]. 757 Dec 42

We used the CO2 laser (group 1) and conventional microsurgery (group 2) for anastomosis of the freshly divided uterine horns of rats and compared the two methods. Each group was then compared with a control group in whom only exploration was carried out at laparotomy. Comparison was done regarding the clinical and histologic results. In addition, serum levels and tissue concentrations of alkaline phosphatase (ALP) and lactic dehydrogenase (LDH) were measured, and the three groups were compared. No significant difference was found between the mean adhesion scores of groups 1 and 2; however, when the control group was compared with the other groups, the differences were statistically significant. The tubal patency rates in groups 1 and 2 and the control group were 83.3%, 79.2% and 100%, respectively, and the pregnancy rates in those groups were 54.5% (6/11), 45.5% (5/11) and 100% (10/10). The differences in tubal patency and pregnancy rates between groups 1 and 2 were not significant, but when each was compared with the control group, the differences were significant. The mean scores for mucosal regeneration and disruption of the muscularis layer in group 1 were significantly lower than those in group 2. Serum levels and tissue concentrations of ALP and LDH in the control group were lower than in groups 1 and 2, and the differences between the control group and each of the other groups were significant; however, no significant difference was found between groups 1 and 2.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Anastomosis of the freshly divided uterine horns of rats with the CO2 laser vs. microsurgery. 772 77

Nine yearling crossbred beef heifers, Bos taurus L., were used to examine physiological responses to horn fly, Haematobia irritans (L.), infestation. Heifers were stanchioned indoors in individual environmentally controlled rooms. On day 0, each animal received 0, 500, or 1,000 horn flies. Fly numbers were adjusted daily to maintain an appropriate infestation for each heifer. Feed intake, respiration rate, and rectal temperature was recorded daily. In addition, blood samples were collected from each animal on days 0, 12, and 33 for serum constituent analysis. To monitor metabolic hormone status, intensive blood samples were also collected hourly for 6 h on days 0, 12, and 33. Throughout the period of treatment, feed intake values were similar among treatments resulting in comparable body weight at the end of the trial. Respiration rates on each day were similar among groups. Rectal temperature was also unaffected by horn fly infestations. Serum electrolyte analysis revealed that neither Na, K, Cl, Ca, P, nor Fe differed among treatments. Likewise, HCO3/CO2 ratio, anion gap, and serum osmolality did not differ among treatment groups. Major indicators of nutrient status (glucose, cholesterol, triglycerides, urea N, creatinine, uric acid, albumin, globulin) and insulin, growth hormone, and prolactin were also unaffected. Serum bilirubin and enzyme (alkaline phosphatase, creatine phosphokinase, gamma-glutamyl transpeptidase, lactic dehydrogenase, aspartate amino transferase, alanine amino transferase) concentrations were similar in control heifers and those infested with horn flies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serum constituent profiles of beef heifers infested with horn flies (Diptera: Muscidae). 783 15

Subclinical intoxication of livestock with Astragalus and Oxytropis species (locoweeds) results in decreased animal feed conversion, reduced weight gains, and reproductive failure. Sensitive diagnostic methods to definitively diagnose and monitor intoxication are needed to minimize these losses and better manage locoweed-infested pastures and rangelands. Sera from cattle grazing locoweed were evaluated for alpha-mannosidase activity, serum biochemical values, electrolytes, and thyroid hormone concentrations. As the cows began to ingest locoweed, the mean serum alpha-mannosidase activities dropped significantly (400.0 microM to 72.5 microM). Changes in other serum chemistry values were less specific; however, individual animals (generally those ingesting more locoweed) had elevated levels of alkaline phosphatase (ALP), aspartate aminotransferase, and lactate dehydrogenase, with decreased serum total protein (5.8 +/- 0.8 g/dl) and albumin (2.3 +/- 0.3 g/dl). Mean serum thyroid concentrations (both T4 and T3) were lower in animals that were ingesting locoweed. The calculated swainsonine dose correlated statistically with serum alpha-mannosidase activity, ALP, albumin, Cl, CO2, and thyroid hormone T3. This correlation suggests that serum alpha-mannosidase activity along with potential changes in ALP, albumin, and thyroid hormone concentrations is a sensitive indicator of locoweed exposure and intoxication. These parameters may also be useful for monitoring intoxication and allowing subclinically affected cattle to be removed from infested areas before irreversible damage occurs.
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PMID:Serum alpha-mannosidase activity and the clinicopathologic alterations of locoweed (Astragalus mollissimus) intoxication in range cattle. 785 27

The effect of concanavalin A (Con A) on maturing and terminal differentiation in permanent chondrocyte cultures were examined. Chondrocytes isolated from permanent cartilage were seeded at low density and grown in MEM medium containing 10% fetal bovine serum, 50 micrograms/ml of ascorbic acid and antibiotics, at 37 degrees C under 50% CO2 in air. At 0.3% of low serum concentration, addition of Con A to the culture medium increased by 3- to 4-fold the incorporation of [35S] sulfate into large chondroitin sulfate proteoglycan that characteristically found in cartilage. Chemical analysis showed a 4-fold increase in the accumulation of macromolecular containing hexuronic acid in Con A-maintained cultures. The effect of Con A on [35S]sulfate incorporation into proteoglycan was greater than that of various growth factor or hormones. Brief exposure of the permanent chondrocytes to Con A (5 micrograms/ml) for 24 hours and subsequent incubation in its absence for 5-10 days resulted in 10- to 100-fold increase in alkaline phosphatase and binding of 1.25 (OH)2 vitamin D3 to cells. Treatment with Con A also resulted in 10- to 20-fold increase in calcium content and 45Ca incorporation into insoluble material. Methyl-D-mannopyranoside reversed the effect of Con A on [35S]sulfate incorporation into proteoglycan and alkaline phosphatase activity. Since other lectins, such as wheat germ agglutinin, lentil lectin, phytohemagglutinin, Ulex europeasu agglutinin and garden pea lectin had been tested to have little effect on [35S]sulfate incorporation into proteoglycans and induction of alkaline phosphatase activity, the Con A action on chondrocytes seems specific. These results indicate that Con A is a potent modulator of differentiation of chondrocytes, which induces the onset on a maturing and a terminal differentiation in chondrocytes, leading to extensive calcification of the extracellular matrix.
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PMID:[Stimulation of maturing and terminal differentiation by concanavalin A in rabbit permanent chondrocyte cultures]. 787 71

To investigate the effect of rapid correction of chronic metabolic acidosis on circulating intact parathyroid hormone (I-PTH) activity by free calcium clamp in chronic renal failure, 18 patients were enrolled in this study. Metabolic acidosis was corrected by continuous bicarbonate infusion while plasma ionized calcium was clamped at the preinfusion level throughout the entire procedure. The plasma pH, bicarbonate, total CO2, sodium, serum total calcium and 1,25(OH)2 vitamin D3 levels increased significantly while serum concentrations of I-PTH, alkaline phosphatase and albumin showed significant decreases after bicarbonate infusion. The plasma ionized calcium, potassium, serum magnesium and inorganic phosphorus levels showed no significant difference before and after bicarbonate infusion. These results demonstrate that rapid correction of metabolic acidosis attenuates circulating PTH activity in chronic renal failure and may underline the importance of maintaining normal acid-base homeostasis particularly in the presence of secondary hyperparathyroidism.
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PMID:Rapid correction of metabolic acidosis in chronic renal failure: effect on parathyroid hormone activity. 796 74

Growth-plate cartilage is organized into four cellular zones containing resting, proliferating, maturing, and hypertrophic cells. Rabbit chondrocytes were isolated from growth-plate costal cartilage of 4-week-old New Zealand rabbits, the cells (15 x 10(4)) were suspended in 1 ml of Iscove's modified Dulbecco's medium (IMDM) with 10% fetal bovine serum, 50 micrograms ascorbic acid, and 60 micrograms kanamycin (medium A), then transferred to a 15 ml of plastic centrifuge tube, and centrifuged at 1500 rpm for 5 min. The cell pellet was incubated at 37 degrees C under 5% CO2 in air. The cultures reorganized into growth plate-like tissue which could be seen 7-14 days after cell seeding. This growth-plate, histologically, was organized longitudinally into cellular columns and horizontally into four cellular zones containing resting, proliferating, maturing and hypertrophic cells. The hypertrophic cells in the upper were large in size and round or oval in shape, the proliferating and the mature chondrocytes in the lower were small in size and spherical or elongated in shape. These chondrocytes were surrounded by an extensive matrix. Biochemically, DNA content of cultures began to rise on the 2nd day after cell seeding and reached a plateau after 10 days later. The uronic acid content increased from day 4 and reached the maximum on day 15. In contrast in the early culture, alkaline phosphatase activity was extremely low, it began to rise on day 9 and was the highest on day 20. The sequential increase of DNA, uronic acid and alkaline phosphatase contents was analogous to the in vivo changes of growth-plate chondrocytes.
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PMID:[Reorganization of growth-plate-like tissue by isolated chondrocytes in culture]. 797 58


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