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)

In the course of the odontogenesis of bovine incisors several clearly distinguishable phosphohydrolase activities are observed in the pulp and in dental hard tissues. Using various substrates and inhibitors, unspecific alkaline phosphatase, two isoenzymes of acid phosphatase, Ca2(+)-activated ATPase and inorganic pyrophosphatase are characterized. The enzymatic activity of alkaline phosphatase in pulp and hard tissues is significantly high at the beginning of dentine and enamel mineralization. The specific activity of this enzyme decreases quite fast with the beginning of root formation, then more slowly, until it reaches a constant final value. Histochemical studies show that during mineralization the maximum of alkaline phosphatase activity is in the subodontoblasts. Lower enzyme concentrations are found in the stratum intermedium and in the outer enamel epithelium during that process. The specific activities of ATPase, acid phosphatases and pyrophosphatase show little temporal variation during tooth development, but they also appear in a characteristic spatial pattern in the dental tissues.
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PMID:Phosphohydrolase activities in developing and mature dental tissues. 216 43

The acute toxicity of lectin ML I from the toxic drug, mistletoe, was demonstrated in previous experiments. Because the reason for this extremely high toxicity is not yet clear, mice were studied histochemically at different times after treatment with various doses of ML I, ML I A or ML I B chain separately, or recombinations of ML I A and ML I B. Various plasma membrane-associated hydrolases as well as Golgi apparatus-and endoplasmic reticulum-linked hydrolases, peroxisomal and extraperoxisomal oxidases, lysosomal hydrolases, mitochondrial dehydrogenases, the cytoskeletal proteins keratin and vimentin as well as iron, glycogen and lipids were analysed in all organs and tissues of female mice. Irrespective of the dose, a clear-cut response was only observed in the liver. After ML I treatment, glycogen disappeared completely from all hepatocytes, and this effect did not depend on the ML I-concentration and exposure time. The increase in activity of Golgi-associated thiamine pyrophosphatase in hepatocytes and of non-specific alkaline phosphatase in the sinusoidal endothelial cells depended on the applied ML I concentration and the time of treatment. Doses of 600 or 900 ng ML I/kg drastically increased the phosphatase activities. These clear-cut changes of glycogen and enzyme activities were not observed after administration of the ML I B chain alone, and less so when the mice were treated only with the ML I A chain, or were treated with a recombination of ML I A and ML I B even at concentrations higher than that of ML I.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Histochemical response of mice to mistletoe lectin I (ML I). 228 17

In the female urethra, the activity and distribution of 15 enzymes was determined by using both conventional and special histochemical methods. The enzymatic equipment differed according to the type of epithelial lining whose variation is characteristic for the female urethra. In the stratified squamous epithelium of the urethra, alkaline phosphatase, beta-glucuronidase, acetyl-beta-D-glucosaminidase, thiamine pyrophosphatase, and glucose-6-phosphatase exhibited but minimal or no activity, yet the other 10 enzymes studied displayed activity particularly in basally situated cells. Nearer to the lumen of the urethra, the activity in the epithelium kept decreasing and was mostly absent in superficial and desquamated cells. In the pseudostratified columnar and in the transitional epithelium of the urethra, the majority of enzymes showed an evenly distributed activity at all epithelial levels. In the apical parts of the most superficially situated cells bounding the lumen of the urethra, a distinct narrow zone of higher activity was observed. It was seen not only on determining the majority of dehydrogenases but also on examining acid phosphatase and naphthyl esterase. The endocrine cells occurring in the uroepithelial lining of the female urethra displayed, yet always with the exception of squamous epithelium (Zaviacic et al. 1983), distinct activity of acid hydrolytic enzymes, and of the enzymes studied it was particularly acid phosphatase. The majority of the demonstrated enzymes, of the dehydrogenases priority, is to be given to succinate dehydrogenase, enabled to differentiate readily between the highly active striated muscle fibers located in the most peripheral parts of the excisions along the urethral circumference and the smooth musculature of the urethral wall with a lower or only minimal activity.
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PMID:The adult human female urethra. Enzyme-histochemical study. 242 Jan 38

The present treatise is a report on the study of morphologic changes induced in the brain of laboratory animals by the exposure to supralethal doses of ionizing radiation. The review of literature summarizes the basic current findings on the interaction between biological objects and ionizing radiation. Principal attention is then paid to literary data describing the morphological changes in the single components of the central nervous system after irradiation. There is a detailed account primarily of what has so far been known on the structure of the blood-brain barrier and its individual, morphologically observable components. What the exploration of literature shows is that problems concerning the morphologic changes following supralethal irradiation have hitherto been paid but little attention. The scarce publications on this topic mostly offer contradicting conclusions. Most of the experiments were made with conventional female rats supplied by the firm Velaz. The animals were exposed to 60Co gamma radiation doses within the range of 15 to 960 Gy. The material for study was sampled in the intervals from 15 min to 6 days after the irradiation had ended. Similar experiments, though on a smaller scale, were carried out with mice, rabbits and dogs. The tissue samples were treated in current methods for the purposes of light microscopy, electron microscopy and histochemistry. The light microscopical pattern of morphological changes during the first hours is dominated by the signs of a cerebral edema. The nerve cells show symptoms of acute swelling. There are small hemorrhages near some of the capillaries. In later periods, the nerve cells assume the nature of pyknomorphous neurons. The degree in which the changes are expressed however varies considerably. Dystrophic changes were also found for glial cells. Small hemorrhages are dispersed over all the areas of the brain. There are persisting signs of brain edema with dilated perivascular and pericellular spaces. The activities of the following enzymes were studied in histochemical examinations: acetylcholinesterase (ACE), nonspecific cholinesterase (CE), alkaline phosphatase (AP), acid phosphatase (AcP), ATP splitting enzyme (ATP), thiamine pyrophosphatase (TPP), glycero-3-phosphate dehydrogenase (GPDH), succinodehydrogenase (SDH), acid nonspecific esterase (AE). A phase progress of activity changes was found for AP, CE, and ACE in the blood capillaries of the brain cortex after the exposure to the radiation doses of 50 to 200 Gy. The irradiation was first followed by elevation of their activity and then, in the intervals of 4 to 24 hours after irradiation, by a drop in their activity below the level obtained for the control animals.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Acute radiation sickness--morphology of CNS syndrome. 253 17

Polyadenylated [poly(A)+] RNA molecules have been isolated from Methanococcus vannielii by oligodeoxythymidylate-cellulose affinity chromatography at 4 degrees C. Approximately 16% of the label in RNA isolated from cultures allowed to incorporate [3H]uridine for 3 min at 37 degrees C was poly(A)+ RNA. In contrast, less than 1% of the radioactivity in RNA labeled over a period of several generations was contained in poly(A)+ RNA molecules. Electrophoretic separation of poly(A)+ RNA molecules showed a heterogeneous population with mobilities indicative of sizes ranging from 900 to 3,000 bases in length. The population of poly(A)+ RNA molecules was found to have a half-life in vivo of approximately 12 min. Polyadenylate [poly(A)] tracts were isolated by digestion with RNase A and RNase T1 after 3' end labeling of the poly(A)+ RNA with RNA ligase. These radioactively labeled poly(A) oligonucleotides were shown by electrophoresis through DNA sequencing gels to average 10 bases in length, with major components of 5, 9, 10, 11, and 12 bases. The lengths of these poly(A) sequences are in agreement with estimates obtained from RNase A and RNase T1 digestions of [3H]adenine-labeled poly(A)+ RNA molecules. Poly(A)+ RNA molecules from M. vannielii were labeled at their 5' termini with T4 polynucleotide kinase after dephosphorylation with calf intestine alkaline phosphatase. Pretreatment of the RNA molecules with tobacco acid pyrophosphatase did not increase the amount of phosphate incorporated into poly(A)+ RNA molecules by polynucleotide kinase, indicating that the poly(A)+ RNA molecules did not have modified bases (caps) at their 5' termini. The relatively short poly(A) tracts, the lack of 5' cap structures, and the instability of the poly(A)+ RNA molecules isolated from M. vannielii indicate that these archaebacterial poly(A)+ RNAs more closely resemble eubacterial mRNAs than eucaryotic mRNAs.
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PMID:Polyadenylated, noncapped RNA from the archaebacterium Methanococcus vannielii. 258 34

Satellite tobacco mosaic virus (STMV) is a plant virus with a 17-nm icosahedral particle encapsidating a 0.3 X 10(6) Mr ssRNA genome that depends on tobamoviruses for its replication. The complete nucleotide sequence of STMV RNA deduced in the experiments described here was 1059 nucleotides in length. The efficiency of labeling viral RNA with [gamma-32P]ATP using T4 polynucleotide kinase was not affected by treatment with tobacco acid pyrophosphatase and/or bacterial alkaline phosphatase, indicating that the majority of the 5' termini of encapsidated STMV RNAs were not phosphorylated. The 240 3'-terminal nucleotides of STMV RNA and either tobacco mosaic virus (TMV) U1 RNA or TMV U2/U5 RNA had greater than 65% overall sequence similarity, with two nearly identical regions of 40 and 50 bases, respectively. There were no other regions of sequence relatedness to TMV RNA. The 19 5'-terminal nucleotides of STMV RNA had greater than 65% sequence similarity with the 16 5'-terminal nucleotides of brome mosaic virus (RNA 3 and 50% sequence similarity with the 12 5'-terminal nucleotides of the Q strain of cucumber mosaic virus RNA 3. The first open reading frame (ORF) beginning at base 53 encoded a 6800 Mr protein that corresponded in size to a major in vitro translation product directed by STMV RNA. A second ORF, beginning at nucleotide 163, had the capacity to code for a protein that corresponded in size (17,500 Mr) to the other major in vitro translation product. The first 12 codons of this ORF corresponded to the sequence of the N-terminal amino acids of the capsid protein. Western-blot analysis of the in vitro translation products revealed that the 17,500 Mr protein had the same electrophoretic mobility as the authentic capsid protein; it was also antigenically related to the capsid protein, but the 6800 Mr protein was not. Time course analysis of in vitro translation demonstrated that the 6800 Mr protein was synthesized at the same time as the capsid protein and did not arise by the proteolytic cleavage of a larger precursor polypeptide. These results suggest that the genome of STMV functioned as a polycistronic messenger RNA. It has not been determined if the 6800 Mr protein is synthesized in vivo. STMV RNA had untranslated regions of 52 and 418 nucleotides at its 5' and 3' termini, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Nucleotide sequence and translation of satellite tobacco mosaic virus RNA. 271 78

In culture, 1-p-bromotetramisole (pBTM), a specific inhibitor of alkaline phosphatase, significantly inhibited the formation of trichloroacetic acid (TCA)-insoluble [32P]-phosphate from inorganic [32P]-phosphate in the proliferating non-mineralizing second (M2) maxillary molar germs but had no effect in the actively mineralizing first (M1) germs. Addition of 10(-5) M inorganic pyrophosphate in the culture medium with a [32P]-phosphate label increased the inhibition of the formation of TCA-insoluble [32P]-phosphate in the M2. pBTM almost completely inhibited the formation of TCA-insoluble [32P]-phosphate from inorganic [32P]-pyrophosphate in the non-mineralizing M2. In the actively mineralizing M1, the compound significantly inhibited but did not abolish the formation of TCA-insoluble phosphate. These results confirm earlier biochemical findings that alkaline phosphatase possesses a pyrophosphatase activity probably related to the turnover of phosphorylated macromolecules necessary for cell differentiation and proliferation.
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PMID:Effect of alkaline-phosphatase inhibition by 1-p-bromotetramisole on the formation of trichloroacetic acid-[32P]-insoluble phosphate from inorganic [32P]-phosphate and [32P]-pyrophosphate in non-mineralizing and mineralizing hamster molar tooth-germs in vitro. 282 59

Thiamine pyrophosphatase was demonstrated in the Golgi complex and acid phosphatase in the GERL of acinar cells of submandibular and parotid glands and were previously demonstrated in cells of intercalary ducts. Thiamine pyrophosphatase was also demonstrated in the Golgi complex of cells of striated and excretory ducts and myoepithelial cells. Acid phosphatase was also demonstrated in lysosomes. Alkaline phosphatase was rarely demonstrated light microscopically at luminal surfaces of striated and excretory ducts and electron microscopically in luminal vesicles in cells of striated ducts. The demonstration of the phosphatases in Golgi complexes and GERLs indicates that investigations on these structures in experimental animals are relevant to human salivary glands and supports the opinion that ductal cells as well as acinar cells secrete organic material. The presence of alkaline phosphatase at luminal surfaces of striated and excretory ducts suggests that resorption as well as secretion may occur in them.
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PMID:Ultrastructural phosphatase histochemistry of submandibular and parotid salivary glands of man. 283 35

An enzyme with FAD pyrophosphatase activity was extracted from human placental syncytiotrophoblast microvilli and purified to near-homogeneity. The enzyme has been identified as 5'-nucleotidase by several criteria. Throughout purification, parallel increases in the specific activities of FAD pyrophosphatase and AMP phosphatase were observed. The enzyme was a glycoprotein with a subunit molecular weight of 74,000. EDTA treatment resulted in a marked decline in both activities, and restoration of FAD pyrophosphatase activity but not 5'-nucleotidase activity was accomplished by the addition of Co2+ or, to a lesser extent, Mn2+. The substrate specificity of the 5'-nucleotidase activity that we observed agreed closely with the results of others. The pyrophosphatase activity was relatively specific for FAD. ADP, ATP, NAD(H), and FMN were not hydrolyzed, and ADP strongly inhibited both activities. For FAD pyrophosphatase activity, a Km of 1.2 x 10(-5) M and a Vmax of 1.1 mumol/min/mg protein were determined in assays performed in the presence of Co2+. In the absence of added Co2+, the Vmax declined but the Km was unchanged. For 5'-nucleotidase (AMP as substrate) the Km was 4.1 x 10(-5) M and the Vmax 109 mumol/min/mg protein. Hydrolysis of FMN to riboflavin was observed in partially purified detergent extracts of microvilli that contained alkaline phosphatase activity and lacked FAD pyrophosphatase and 5'-nucleotidase activity. The presence of both FAD pyrophosphatase and FMN phosphatase activities in syncytiotrophoblast microvilli supports the view that the placental uptake of vitamin B2 involves the hydrolysis of FAD and FMN to riboflavin which is then absorbed, a sequence postulated for intestinal absorption and liver uptake.
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PMID:5'-Nucleotidase of human placental trophoblastic microvilli possesses cobalt-stimulated FAD pyrophosphatase activity. 284 89

New light microscopic visualization methods were developed for the histochemical detection of non-specific alkaline and acid phosphatase, Mg-, Ca- and Na, K-dependent adenosine triphosphatase, myosin adenosine triphosphatase, glucose-6-phosphatase, 5'-nucleotidase and thiamine pyrophosphatase with cerium ions as trapping agents in cryostat and plastic sections. The techniques are based on the conversion of cerium phosphate into cerium perhydroxide by H2O2 which decomposes at 55 degrees-60 degrees C into cerium hydroxide and oxygen radicals. These radicals are able to oxidize diaminobenzidine (DAB) to DAB brown. Addition of nickel ions to the DAB-H2O2 mixture generates bluish-black stained nickel-DAB complexes. Compared with the classical metal precipitation, azo, azoindoxyl and tetrazolium procedures the H2O2-DAB and especially the H2O2-DAB-nickel methods provided identical or superior results in catalytic phosphatase histochemistry and immunohistochemistry when using non-specific alkaline phosphatase as the enzyme label.
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PMID:The cerium perhydroxide-diaminobenzidine (Ce-H2O2-DAB) procedure. New methods for light microscopic phosphatase histochemistry and immunohistochemistry. 285 63


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