Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PHOSPHATASES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 541 records · Page 30Linked to original sources
PubMed1986

Quantitative method for determining serum alkaline phosphatase isoenzyme activity II. Development and clinical application of method for measuring four serum alkaline phosphatase isoenzymes.

A method for quantitating the liver, bone, intestinal and placental alkaline phosphatase activity of serum, using an algorithm for converting selective inactivation by guanidine hydrochloride, L-phenylalanine, and heat into equivalent isoenzyme activity is described. The method can individually quantify mixtures of isoenzymes to within a margin of 3%; it has acceptable reproducibility and has been used to develop both age and sex related reference ranges. Analysis time is about 30 minutes. The clinical reliability of this method has been shown in a study of 101 patients, in 79% of whom isoenzyme results were compatible with the final clinical diagnosis; in 10% a clinical diagnosis resulted from isoenzyme analysis, and in a further 11% the source of the increased alkaline phosphatase activity was identified and supported by electrophoresis, with a definite clinical diagnosis yet to be made.

Adult↗
PubMed1994

Improved double immunohistochemical staining method for cryostat and paraffin wax sections, combining alkaline phosphatase anti-alkaline phosphatase and indirect immunofluorescence.

AIMS: To develop and immunohistochemical staining method for cryostat and paraffin wax sections so that two different antigens in the same section of tissues could be detected by combining immunoenzyme and immunofluorescence techniques. METHODS: This double immunohistochemical staining method combines alkaline phosphatase-anti-alkaline phosphatase (APAAP) using New Fuchsin as a chromogen and indirect immunofluorescence. RESULTS: APAAP staining for one antigen of this double immunohistochemical staining method was observed under bright field conditions alternating with immunofluorescence for another antigen under ultraviolet light. The double exposed photograph of both easily identified the two signals within the same cell. CONCLUSIONS: This double immunohistochemical staining method can overcome the disadvantages of any masking effect of the double immunoenzymatic methods and the background problems of double immunofluorescence method especially when applied to paraffin wax sections. It also permits good morphological identification of the doubly stained cells which may be of crucial importance in studies on pathology specimens.

Alkaline Phosphatase↗
PubMed2002

Comparative modeling of the phosphatase and kinase domains of protein tyrosine phosphatase and insulin receptor kinase from Drosophila melanogaster (DPTP61fm), and a computational study of their mutual interactions.

The components and functions of the insulin receptor kinase signaling pathway have been conserved in a broad range of Metazoa ranging from mammals to insects and nematodes. There is a high degree of sequence homology and functional similarity between the human insulin receptor kinase (IRK) and the drosophila (Drosophila melanogaster) form (DIRK) of this enzyme. Similarly, a high degree of homology exists between human protein tyrosine phosphatase 1B (PTP1B) (which directly regulates IRK) and its drosophila counterpart DPTP61F (DPTP). However, genetic and biochemical studies have yet to demonstrate that DPTP61F acts in the DIRK pathway. Comparative structural modeling techniques using the known structures of human IRK and PTP1B as templates have yielded structures for the drosophila enzymes. The derived structures confirm that there is a high level of structural conservation at the tertiary level. Association of the DIRK and DPTP enzymes with each other was then investigated with a view to ascertaining whether DIRK might be a substrate of the DPTP. Evaluation of the interaction surfaces, including hydrophobic patch, shape, hydrogen bonding, and electrostatic compatibility, strongly suggested that the drosophila insulin receptor is a substrate of the DPTP. The interaction surfaces of the human and drosophila enzymes are structurally similar, although changes in critical residues modify possible electrostatic and hydrogen-bonding interactions. This suggests that in the mixed systems, DPTP-IRK or PTP1B-DIRK, the kinase domain will be a comparatively poor substrate for phosphatase activity when compared with the native systems.

Amino Acid Sequence↗
PubMed1991

The use of the alkaline phosphatase-antialkaline phosphatase technique for immunophenotyping acute myeloid leukemia.

The leukemic cells from 31 cases of acute myeloid leukemia were immunophenotyped by the alkaline phosphatase-antialkaline phosphatase (APAAP) technique, using 7 monoclonal antibodies reactive with cells of myeloid origin. We found a good correlation between the results obtained using the APAAP method and indirect immunofluorescence. In most cases, we observed a slight degree of variation in the percentages of reacting cells when comparing the two methods. Nevertheless, taking 20% of cells being immunolabeled as a threshold for defining a case as positive, we found no discrepancies in the final classification of each case. The main advantages of the APAAP method are: (1) its use with routinely prepared peripheral or blood marrow samples, and (2) the possibility of correlating immunological characterization with morphology. Since the results with the APAAP method were comparable with those obtained using indirect immunofluorescence, we suggest that this former technique can complement, and sometimes substitute, other methods of immunological evaluation.

Alkaline Phosphatase↗
PubMed1983

Acid phosphatases of the human placenta, characterization and immunological comparison with prostatic acid phosphatase.

Four different acid phosphatases, denoted A1, A2, B and C, were separated from human placental homogenates. The enzymes A1, A2 and B were separated from enzyme C by binding to concanavalin A-Sepharose. Although the A1, A2 and B enzymes were all strongly inhibited by L-tartrate, only the A1 enzyme bound by affinity chromatography to L-tartrate-Sepharose. The A2 and B enzymes were separated on DEAE-cellulose. A1, A2 and B had molecular weights about 95,000. Enzyme B had high KM, whereas enzymes A1 and A2 had low KM. The enzymes A1 and A2 bound to antibodies raised against prostatic acid phosphatase, whereas the enzymes B and C did not.

Acid Phosphatase↗
PubMed1989

High degree of homology between primary structure of human lysosomal acid phosphatase and human prostatic acid phosphatase.

Alignment of the amino-acid sequences of the human lysosomal acid phosphatase (LAP) and human prostatic acid phosphatase (PAP) yielded an extensive homology between the two mature polypeptide chains. In the overlapping part, which extends over the entire PAP sequence and the N-terminal 90% of the LAP sequence, the identity is 49.1%. The LAP has an additional C-terminal sequence, which is encoded by the last exon of the LAP gene. This sequence contains the transmembrane domain of LAP, which is lacking in the secretory PAP. All six cysteine residues as well as 20 out of 27 (LAP) and 26 (PAP) proline residues present in the overlapping part of the proteins are conserved, suggesting that they are involved in stabilization of the tertiary structure of both proteins. Only two out of 8 N-glycosylation sites in LAP and 3 in PAP are conserved, suggesting that the dense N-glycosylation of LAP is related to its function in lysosomes.

Acid Phosphatase↗
PubMed1991

An improved method of alkaline phosphatase--antialkaline phosphatase immunophenotyping using microwave irradiation.

The application of microwave irradiation from a domestic microwave oven to the alkaline phosphatase-antialkaline phosphatase immunophenotyping has resulted in substantial time saving of the procedure. This has been achieved without compromising the quality of the final preparation. It can be carried out on peripheral blood smears, bone marrow smears and cytocentrifuge preparations on fresh slides, slides that have been stored at -20 degrees C wrapped in aluminium foil and unfixed smears left at room temperature for up to 8 days.

Alkaline Phosphatase↗
PubMed1988

Acid phosphatase as a selective marker for a class of small sensory ganglion cells in several mammals: spinal cord distribution, histochemical properties, and relation to fluoride-resistant acid phosphatase (FRAP) of rodents.

Fluoride-resistant acid phosphatase (FRAP) activity as characterized in rat and mouse was studied in sensory ganglion and spinal cord of several mammals, using both the Gomori lead-ion capture and azo-dye coupling methods. FRAP was specifically localized to small- and medium-diameter primary afferent neurons and inner substantia gelatinosa of all nonrodent animals studied, including rabbit, cat, dog, monkey, cow, and human. In rabbit, sciatic nerve transection resulted in depletion of enzymatic activity in ipsilateral spinal cord dorsal horn in a pattern corresponding to the distribution of central terminals of the nerve. Further analysis of the substrate specificity and pH dependence of FRAP was carried out primarily in rat sensory ganglion and spinal cord; the enzyme was found to hydrolyze a wide variety of phosphomonoesters in a relatively nonselective manner at both pH 5 and pH 7, including 5'-nucleotides, phosphorylated amino acids, and several exogenous compounds. The visualization of FRAP-like activity in several nonrodent species is discussed with reference to previous work indicating its presence only in mouse and rat. Technical factors are considered that limit the applicability of the lead-ion histochemical method in demonstration of FRAP and in efforts at functional characterization of the enzyme, especially in light of its ability to hydrolyze a broad spectrum of substrates over a wide pH range. Alternative interpretations of the expression of acid phosphatase activity in a select class of small sensory ganglion cells are suggested, including several possible non-synaptic roles of FRAP in the peripheral nervous system.

Acid Phosphatase↗
PubMed1988

Color-contrast staining of two different lymphocyte subpopulations: a two-color modification of alkaline phosphatase monoclonal anti-alkaline phosphatase complex technique.

A dual staining method for different human lymphocyte subpopulations with nonoverlapping antigen distribution patterns is described. Cytocentrifuge slide preparations of peripheral blood nonadherant mononuclear cells (NAMNC), bone marrow aspirate or buffy coat smears were fixed in acetone and incubated with a primary mouse monoclonal antibody (MAb) against a lymphocyte antigen (CD8, Ig-light-chain, CD19, CD4) followed by rabbit anti-mouse immunoglobulin (Ig) and the alkaline phosphatase monoclonal anti-alkaline phosphatase (APAAP) complex. After repeating the "bridge" antibody and the APAAP, a red product was developed with fast red TR-naphthol AS-BI phosphate. Following this one-color stain the process was repeated using a different primary mouse MAb against another lymphocyte antigen (CD4, Ig-light chain, CD3, MHCII DR, CD5) and fast blue BB-naphthol AS-MX phosphate at the last step to yield a blue product. Control slides stained by the standard one-color APAAP method with the relevant primary MAb showed that there was no nonspecific labelling and the percent of positive cells in a given test was almost identical. To achieve an intense blue in the second stain for some antigens, e.g., CD4, either the MAb concentration had to be increased or two different MAbs recognizing differing epitopes of the same antigen, e.g., T1 and UCHT2 for CD5, were applied. Any change of red to purple at the site of the first stain after 15 min exposure to the blue-yielding AP substrate is due to residual AP activity of the first stain rather than to crossbinding of immunoreagents.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMedDate not supplied

Metastatic workup of patients with prostate cancer employing alkaline phosphatase and skeletal alkaline phosphatase.

PURPOSE: To compare the efficacy of two tests, alkaline phosphatase (AP) and skeletal alkaline phosphatase (SAP) as staging markers to discriminate patients with cancer of the prostate (CaP) with bone metastases (M+) from those without bone metastases (Mo). MATERIALS AND METHODS: Patients with previously untreated CaP were entered in the retrospective analysis. Serum concentrations of AP (n = 215) and SAP (n = 73) were available. After staging the patients could be divided into 2 groups: Group I: patients with CaP and bone metastases (cT2-4 NxMoss AP: n = 40; SAP: n = 21) Group II: patients with CaP without bone metastases (cT3-4 Nx Mo; pT1-3 No Mo; AP: n = 175; SAP: n = 52). RESULTS: None of the Mo patients but 71% of the M+ patients exhibited a SAP value above the reference range (< 19 ng/ml). This difference is statistically significant (p < 0.001) and resulted in a sensitivity and specificity of 71% and 100%, respectively. The Youden-index is 0.7. In contrast 7% of the Mo patients and only 13% of the M+ patients exhibited a AP value above the reference range (< 170 U/l). This difference is statistically not significant (p = 0.71) and resulted in a sensitivity and specificity of 13% and 93%, respectively. The Youden-index is 0.06. CONCLUSION: SAP could become a useful marker in the evaluation of patients with newly diagnosed CaP as it provides more information than AP concerning the skeletal status of these patients.

Adult↗
PubMed1992

DNA polymorphism of alkaline phosphatase isozyme genes: linkage disequilibria between placental and germ-cell alkaline phosphatase alleles.

The use of human placental alkaline phosphatase (PLAP) cDNA as a probe allows the detection and identification of restriction DNA fragments derived from three homologous genes, i.e., intestinal alkaline phosphatase (AP), germ-cell AP (GCAP), and PLAP. In previous RFLP studies we have reported linkage disequilibria between an RsaI and two PstI (a and b) polymorphic restriction sites and electrophoretic types of PLAP. In this report we present evidence that, in spite of the strong correlation with PLAP types, PstI(b) is an RFLP of GCAP. The data indicate close linkage between the PLAP and GCAP loci.

Alkaline Phosphatase↗
PubMed1990

High-molecular-weight alkaline phosphatase and alkaline phosphatase lipoprotein X complex in cholestasis and hepatic malignancy.

Alkaline phosphatase (ALP) fast liver isoenzyme is now known as high-molecular-weight ALP. This ALP isoenzyme represents fragments of hepatic cell plasma membranes with various membrane-bound enzymes localized on the surface. High-molecular-weight ALP isoenzyme is present in patients' serum samples in conditions associated with intrahepatic and extrahepatic cholestasis and primary or metastatic hepatic malignancy. High-molecular-weight ALP isoenzyme may coexist with ALP of the normal liver and with ALP lipoprotein X. Alkaline phosphatase ultrafast liver isoenzyme is now known as ALP lipoprotein X complex.

Adult↗
PubMed1985

[Alkaline phosphatase in human lymphocytes. II. A method for ultracytochemical detection of alkaline phosphatase in lymphocytes].

For the ultracytochemical identification of alkaline phosphatase in lymphocytes gained from the peripheral blood of healthy individuals a sensitive method is described which allows the low enzyme activity of these cells to be determined. This was possible because the authors succeeded in stabilizing lead ions in the alkaline medium by forming a complex directly between tris-(hydroxymethyl) aminomethan and lead (II) citrate. AP localized ultrachemically in lymphocytes in particular formations similar to phosphasomes of neutrophilic granulocytes. In those lymphocytes stimulated by lipopolysaccharides a high enzyme activity could be observed and, in addition to phosphasomes, the product of response can also be found in canal-like structures of the endoplasmatic reticulum. These findings contribute to clarify the ultrastructural localization of alkaline phosphatase in lymphocytes and may be regarded as an aid in discovering the importance of the enzyme in the biology of lymphocytes or in its activation, respectively.

Alkaline Phosphatase↗
PubMed1987

Immunophenotyping of acute myeloid leukemia using monoclonal antibodies and the alkaline phosphatase-antialkaline phosphatase technique.

The leukemic cells from 41 cases of acute myeloid leukemia (AML) and 17 cases of acute lymphocytic leukemia (ALL) were immunophenotyped by the alkaline phosphatase-antialkaline phosphatase (APAAP) immunocytochemical technique utilizing eight monoclonal antibodies (MoAb) reactive with cells of myeloid origin and seven MoAb reactive with lymphoid antigens. Ninety percent of the cases of AML reacted with one or more of the pan-myeloid MoAb, My7, My9, or 20.3. Reactivity of the myeloid panel of MoAb showed some correlation with the French-American-British (FAB) classification of AML. Five of six cases of acute promyelocytic leukemia (APL) were HLA-DR negative; the one HLA-DR-positive APL had a minor population of HLA-DR-negative promyelocytes. OKM5 and/or My4 reacted with 16 of 16 monocytic leukemias. No specific marker of early erythroid development was identified. AP3, a MoAb reactive with platelet glycoprotein (GPIIIa), was specific for acute megakaryoblastic leukemia. Immunocytochemistry was also helpful in classifying seven cases of AML with equivocal or negative routine cytochemistry. Two cases of AML had minor populations of blasts detected by the APAAP technique that were immunologically distinct from the major blast population; these minor populations emerged as the predominant cell type at relapse. Two cases of ALL expressed multiple myeloid and lymphoid antigens. Two other cases that morphologically were ALL reacted with only myeloid MoAb; one consisted entirely of immature basophils on ultrastructural examination. Immunophenotyping results using the APAAP technique were comparable with those obtained with flow cytometry. The APAAP technique is a reliable method for immunophenotyping leukemia that complements other methods of immunologic evaluation. The primary advantages of this method include its use with routinely prepared blood and bone marrow smears and the ability to correlate immunocytochemical reactions with morphology.

Alkaline Phosphatase↗
PubMed1986

Acid phosphatase activity in mononuclear phagocytes and the U937 cell line: monocyte-derived macrophages express tartrate-resistant acid phosphatase.

Tartrate-resistant acid phosphatase (TRAcP) is used as a marker for osteoclasts, which are believed to be derived from phagocytic cells or phagocyte stem cell precursors. To further investigate the relationship between monocytic phagocytes and osteoclasts, acid phosphatase (AcP) activity was measured by three different techniques in human peripheral blood monocytes, monocyte-derived macrophages, and the U937 cell line. We found that cytochemistry and gel electrophoresis led to similar results, but that the colorimetric assay was inconsistent. Normal human peripheral monocytes expressed both tartrate-sensitive and -resistant AcP. In culture these cells formed polykaryons and expressed TRAcP activity that was further identified as an isoenzyme associated with bone tissue. In contrast, the U937 cells did not express TRAcP activity as measured by gel electrophoresis. Both U937 cells and monocytes possess material that interferes with interpretation of the colorimetric assay of AcP. The presence of TRAcP in monocyte-derived macrophages further supports the relationship between phagocytic cells and bone osteoclasts.

Acid Phosphatase↗
PubMed1979

Use of specific inhibitors to disciminate alkaline phosphatase isoenzymes originating from human liver, placenta and intestine: absence of meconial alkaline phosphatase in maternal serum.

We used the inhibitors bromotetramisole, L-phenylalanine amide, and L-phenylalanine in combination to measure intestinal phosphatase in maternal serum and amniotic fluid. By using high concentrations of these inhibitors, it was possible to measure the three isoenzymes separately. We found no evidence of the presence of meconial alkaline phosphatase in the serum of the mother (six cases) after meconial passage in utero.

Alkaline Phosphatase↗
PubMed1982

Protein phosphatase activity in cell nuclei of rat liver and its relationship to the protein phosphatase in the cytoplasm.

Nuclear protein phosphatase (phosphoprotein phosphohydrolase, EC. 3.1.3.16, abbreviated: NPPase) was extracted from rat liver cell nuclei and subnuclear fractions under different conditions. NPPase activity proved to be strongly bound to chromatin and its presence cannot be explained by an incomplete removal of the cytoplasm from nuclear preparations. The small extent of activation of NPPase after treatment with ethanol or mercaptoethanol suggests that NPPase is present in the nucleus in its activated form. On the other hand, cytoplasmic protein phosphatase (abbreviated: NPPase) from rat liver also showed only a small extent of activation after precipitation with ammonium sulphate or ethanol. Therefore, the pronounced activation of cytoplasmic PPase, which has been observed in rabbit liver and skeletal muscle, cannot be used for differentiation between cytoplasmic and nuclear PPases in rat liver.

Animals↗
PubMed1978

Selective purification of tartrate-inhibitable acid phosphatases: rapid and efficient purification (to homogeneity) of human and canine prostatic acid phosphatases.

We describe the synthesis of a long-chain monoamide derivative of L(+)-tartaric acid and its attachment to Sepharose 4B. Procedures are then described for use of this material in purifying human prostatic and (for the first time) canine prostatic acid phosphatases to constant specific activity and electrophoretic homogeneity. Depending on sample size, such purification is possible in one step, and is clearly faster and more efficient than are previously described methods. These materials and procedures have significant potential in studies of the comparative biochemistry and clinical chemistry of tartrateinhibitable acid phosphatases.

Acid Phosphatase↗