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)

Colorectal epithelium is composed of a variety of cell types, including absorptive, mucous and endocrine cells. All of these cell types are thought to arise from stem cells located at the base of the crypt. However, the factors which control these differentiation pathways are poorly understood. In attempts to establish differentiated in vitro systems, one approach has been to grow primary human colorectal adenocarcinomas as cell lines. Some of these cell lines retain a sufficient number of the differentiated features of their tissue of origin to make them useful experimental systems for studying differentiation. This study describes the characterisation of such a cell line, the HRA-19 line. HRA-19 cells were derived from a primary human rectal adenocarcinoma. The cells grew as monolayers in vitro on tissue-culture plastic and remained pleomorphic even after 150 passages in vitro. Some colonies of cells expressed alkaline phosphatase activity, an enzyme normally expressed in vivo by absorptive cells of the upper crypt and surface epithelium. No evidence of differentiation into goblet or endocrine cells was obtained in monolayer cultures of HRA-19 cells. Xenografts of this cell line contained cells with the ultrastructural characteristics of absorptive and endocrine cells. These endocrine cells exhibited Grimelius silver staining, displayed formaldehyde-induced fluorescence and contained many basally located, electron-dense granules. When grown as monolayers, clones of this cell line retained the heterogeneity with respect to morphology and alkaline phosphatase expression of the parent cell line. It is proposed that this cell line is derived from malignant progenitor cells which retain the ability to differentiate.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endocrine differentiation by a human rectal adenocarcinoma cell line (HRA-19). 356 97

A number of immunocytochemical detection systems for determining the chromosomal localization of specific nucleic acid sequences by non-radioactive in situ hybridization have been compared. The procedures were: 1. the peroxidase/diaminobenzidine (PO/DAB) combination, either or not gold/silver intensificated; 2. alkaline phosphatase marking using the nitro-blue tetrazolium plus bromochloro-indolyl phosphate substrate combination (AP/NBT + BCIP); and 3. immunogold with or without silver enhancement. The procedures were first tested and optimized in dot blot experiments and then applied to in situ hybridization. As hybridization probes, both a middle-repetitive and a unique sequence (modified with 2-acetylaminofluorene (AAF] were used. The advantages and disadvantages of the various methods for reflection contrast (RC) or transmission electron microscopic (TEM) visualization of hybrids are discussed.
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PMID:Non-radioactive in situ hybridization. A comparison of several immunocytochemical detection systems using reflection-contrast and electron microscopy. 361 Jun 73

The major scrapie prion protein, designated PrP 27-30, exhibited both charge and size heterogeneity after purification from infected hamster brains. Eight or more discrete charge isomers of PrP 27-30 with isoelectric points ranging from approximately pH 4.6 to 7.9 were found by using non-equilibrium pH gradient electrophoresis in the first dimension followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. The charge isomers were detected by silver staining as well as by radioiodination. The procedures used to disaggregate PrP 27-30 before electrophoresis in the first dimension do not appear to be responsible for the charge heterogeneity. However, heating PrP 27-30 to 100 degrees C for 15 min in 0.1 N NaOH or 0.1 N HCl resulted in modification of the protein and alteration of its electrophoretic pattern. A PrP 27-30 fragment (molecular weight, 17,100 to 21,900) obtained by cyanogen bromide cleavage also exhibited charge and size heterogeneity. Periodic acid-Schiff staining of PrP 27-30 electrophoresed into sodium dodecyl sulfate-polyacrylamide gels demonstrated that carbohydrate residues are attached to the protein. Digestion of PrP 27-30 with neuraminidase and endo-beta-N-acetylglucosaminidase H resulted in significant changes in the isoelectric pH of PrP 27-30 isomers, whereas digestion with alkaline phosphatase had no effect. Our results demonstrate that PrP 27-30 is a sialoglycoprotein; this is consistent with several properties of this protein and of the scrapie prion.
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PMID:Scrapie PrP 27-30 is a sialoglycoprotein. 391 76

Alkaline phosphatase of matrix vesicles isolated from fetal bovine epiphyseal cartilage was purified to apparent homogeneity using monoclonal antibody affinity chromatography. The enzyme from the butanol extract of matrix vesicles bound specifically to the immobilized antibody-Sepharose in the presence of 2% Tween 20 whereas the major portion of nonspecific protein was removed by this single step. Of various agents tested, 0.6 M 2-amino-2-methyl-1-propanol, pH 10.2, was the most effective in eluting 80-100% of the enzyme initially applied. Both Tween 20 and 2-amino-2-methyl-1-propanol associated with the eluted enzyme were effectively removed by the sequential application of DEAE-cellulose and Sepharose CL-6B chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the enzyme preparation treated with sodium dodecyl sulfate and mercaptoethanol showed the presence of a dominant band (using silver staining) corresponding to a molecular weight of 81,000. This molecular weight was nearer reported values for rat liver (Ohkubo, A., Langerman, N., and Kaplan, M. M. (1974) J. Biol Chem. 249, 7174-7180) and porcine kidney (Cathala, G., Brunel, C., Chapplet-Tordo, D., and Lazdunski, M. (1975) J. Biol. Chem. 250, 6040-6045) alkaline phosphatase, than to previously reported values for chicken (Cyboron, G. W., and Wuthier, R. E. (1981) J. Biol. Chem. 256, 7262-7268) and fetal calf (Fortuna, R., Anderson, H. C., Carty, R. P., and Sajdera, S. W. (1980) Calcif. Tissue Int. 30, 217-225) cartilage matrix vesicle alkaline phosphatase. The purified alkaline phosphatase was activated by micromolar Mg2+. The amino acid composition of cartilage alkaline phosphatase was found to be similar to that previously described for porcine kidney (Wachsmuth, E. D., and Hiwada, K. (1974) Biochem. J. 141, 273-282). Double immunoprecipitation data indicated that monoclonal antibody against cartilage alkaline phosphatase cross-reacted with fetal bovine liver or kidney enzyme but failed to react with calf intestinal or rat cartilage enzyme. Thus these observations suggest that alkaline phosphatase of matrix vesicles from calcifying epiphyseal cartilage is a liver-kidney-bone isozyme.
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PMID:Purification and partial characterization of alkaline phosphatase of matrix vesicles from fetal bovine epiphyseal cartilage. Purification by monoclonal antibody affinity chromatography. 396 87

Isolated human syncytiotrophoblast microvillous plasma membranes (StMPM) have been examined by electron microscopy, SDS-polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional PAGE (2D-PAGE), and immunoblots. Electron microscopy of StMPM pellets revealed populations of membrane-bounded vesicles that disrupted after treatment with the chaotrope 3M KCl for 16 hr; with increasing molarity of another chaotrope (NH4SCN), the vesicles became smaller and more homogeneous. NH4SCN treatment resulted in significant reduction on SDS and 2D-PAGE analysis of only one protein at 80kd, shown by immunoblotting to be transferrin; 3M KCl had little effect and appeared to be a poor chaotrope. Chromogenic silver staining of SDS-PAGE gels demonstrated over 50 StMPM-associated discrete protein components. Immunoblotting revealed transferrin (80kd), albumin (65kd), IgG heavy chain (56kd), and Gc protein (56kd). Alpha-2-macroglobulin (alpha 2M) was identified at 180kd and 95kd; the smaller component may be a proteolytic derivative indicating alpha 2M binding to a trophoblast surface protease. Numerous discrete protein dots, and groups of dots characteristic of charge heterogeneity of individual proteins, were observed on high resolution 2D-PAGE. The most intensely stained proteins were transferrin (80kd), albumin (65kd), placental-type alkaline phosphatase (66kd), and actin (46kd). This 2D-PAGE technique is a superior method for analyzing the trophoblast membrane proteins, and the system described will enable systematic mapping of these components.
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PMID:Biochemical studies of human placental microvillous plasma membrane proteins. 403 72

Undecalcified bone fixed in a variety of fixatives and embedded in a new formulation of 2-hydroxypropyl methacrylate at 4 c has been sectioned at 1 to 5 microns. The embedding mixture contains 2-butoxyethanol as plasticizer and triethyleneglycol dimethacrylate as cross-linker. The accelerator was benzoyl peroxide and the catalyst was N,N-dimethylaniline. With proper embedding and care in sectioning it is possible to obtain sections with relatively little bone compression, excellent preservation of cellular elements, and a minimum of wrinkling. A wide variety of stains have been used for these sections and those reported here are Gill's hematoxylin-eosin, Nocht's azure-eosin, Feulgen, Hoechst 33258 (bisbenzimid H 33258), methyl green-pyronin, PAS, alizarin red, and von Kossa silver stain. There was excellent preservation of acid and alkaline phosphatase activities. A new method of prestaining immunofluorescent labeling was also applied to bone and examples of staining with anticollagen I and antifibronectin are presented.
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PMID:Staining and histochemistry of undecalcified bone embedded in a water-miscible plastic. 616 50

The adrenal components of C. mrigala are embedded in the pronephric cephalic kidney around the post cardinal vein. The cortical cells responded positively to the lipids, ascorbic acid, delta 5-3 beta-HSD, G-6-PD, MAO, acid and alkaline phosphatase tests. The presence of intense MAO activity may suggest the possible involvement of monoamines in the adrenocortical function. Localization of lipids and delta 5-3 beta-HSD show the sites of corticosteroid synthesis. In the chromaffin cells, MAO, acid and alkaline phosphatase activity was moderate whereas they gave a strong reaction to ascorbic acid test in comparison to the cortical cells. Noradrenaline (NA) and adrenaline (A) storing cells were differentiated adopting glutaraldehyde silver, dichromate and iodate techniques. NA and A storing cells are almost totally depleted of their contents after reserpine treatment. The histochemical response of the adrenal gland of this species is largely comparable to that of higher vertebrates.
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PMID:A histochemical study on the adrenal components of the teleost Cirrhinus mrigala (Ham.). 625 48

The localization of alkaline phosphatase activity in the lumbosacral region of the developing spinal cord was studied in 9.5- to 17.5-day mouse embryos. The activity was uniformly distributed in the pseudostratified neuroepithelium of the 9.5-day cord. In the 11.5-day cord in which the lateral motor columns were being formed, the enzymatic activity was localized in the ventrolateral sector of the cord. The enzyme-positive ventricular cells tended to be located medially whereas radially oriented enzyme-positive processes extended into the marginal layer. The 13.5-day cord displayed a similar distribution pattern, but there were many more radial processes and the enzyme-positive cells had spread laterally. Close apposition between the processes and the ventricular cells was observed. By 15.5 and 17.5 days, when the intermediate layer was fully developed and the ventricular layer had regressed to a thin ependyma, the activity had become diffusely located in the ventral half of the cord. The enzyme-positive cells and processes became less conspicuous. The silver-stained processes in the cord were found to be organized in an entirely different pattern from that of the enzyme-positive processes, suggesting that the enzyme-positive processes were not neuronal processes. The enzymatic activity found in the developing spinal cord may be associated with the migration of neuroblasts along the radially aligned processes.
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PMID:The pattern of alkaline phosphatase activity in the developing mouse spinal cord. 649 83

The Backscattered Electron Imaging (BEI) mode of Scanning Electron Microscopy (SEM) has been applied to the study of cells stained with various heavy metals in cytochemical reactions. Improvements or modifications of some of these methods and their application to the study of normal and leukemic leukocytes have been evaluated in this report. The results obtained after staining peroxidase-positive granules with osmium, copper, cobalt-nickel and gold-cobalt are compared. Granules containing non-specific esterase activity were demonstrated in the BEI mode after incubation of the cells in Hanker medium and staining with osmium. While sites of acid phosphatase activity were easily localized with a conventional lead method, alkaline phosphatase activity was demonstrated only in the phagocytic vacuoles of cells previously incubated with latex particles and subsequently stained with lead. Cell nuclei were identified in the BEI mode after silver methenamine or bismuth staining. Combining their cell surface and cytochemical characteristics a more accurate identification of the different blood cell types with the SEM becomes possible.
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PMID:Cytochemical methods for the backscattered electron imaging mode of scanning electron microscopy: further applications to the study of human leukemic cells. 666 47

Bilaterally ovariectomized rats (Sprague-Dawley) were used to study the early effects of benzo(a)pyrene (BP) on the morphology and cytochemistry of vaginal epithelium. BP (50 mg/kg) was administered subcutaneously in 0.5 ml corn oil and dosing was daily for 2--6 days. Animals were sacrificed 24 hr after the last dose; and vaginal tissue was processed separately for light and electron microscopy, and ultracytochemistry. The results indicate that BP alone induces mucification, mitosis and DNA synthesis in the superificial and basal comportmanets of vaginal epithelium, and DNA synthesis in the submucosal layer. BP also enhances alkaline phosphatase activity and glycogenesis. Alkaline phosphatase is present in the plasma membranes of various cells and in the membranes delimiting secretory granules. Increased alkaline phosphatase is associated with cell growth and proliferation, and also with mucin formation and secretion. Glycogen is relatively abundant in the intermediate cells and parabasal cells. Further, periodic acid-silver methenamine staining indicates that secretory granules and mucin contain glycoproteins. An examination of the fine structure of mucocytes reveals that Golgi complex and granular endoplasmic reticulum are involved in the fabrication of mucin which is secreted by apocrinal and exocytotic processes. Increased mucification was observed after two days (2 doses) and intensified up to 6 days (6 doses). These findings provide evidence that BP is mucinogenic and mitogenic agent to vaginal epithelium in spayed rats without the presence of exogenous ovarian hormone promoting or inducing factors.
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PMID:Early response of vaginal epithelium to benzo[a]pyrene in ovariectomized rat: morphological and cytochemical studies. 693 75


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