Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
 4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Effects of the dopamine agonist 2-bromo-alpha-ergocryptine (bromocriptine) on plasma and pituitary PRL and enzyme activities in lactating and postlactating rats have been investigated. Lactating rats which had been suckling their young for 3 days were given a single sc injection of bromocriptine or solvent. The treated and control animals were divided into 2 further groups. One group (lactating rats) was permitted to suckle their pups for a further 12 or 24 h; the young were removed from the other group (postlactating rats). Homogenates were prepared from the anterior pituitaries and assayed for organelle marker enzyme activities. When 0.5-500 micrograms bromocriptine were administered to lactating rats for 24 h, pituitary PRL was increased by all doses, but only the 500-micrograms dose significantly reduced plasma PRL. Total protein was unchanged, lysosomal acid PRL proteolytic activity increased 8-fold, N-acetyl-beta-glucosaminidase and beta-glucuronidase (lysosomes) were unchanged, acid phosphatase (lysosomes and endoplasmic reticulum) was increased by three of four doses, 5'-nucleotidase and alkaline phosphatase (plasma membrane) were increased 4-fold, neutral-alpha-glucosidase (endoplasmic reticulum) and malate dehydrogenase (mitochondria) were unchanged, and catalase (peroxisomes) was significantly increased. Bromocriptine (500 micrograms) administration to lactating and postlactating rats for 12 and 24 h significantly decreased the pituitary DNA but not the total protein content of the pituitaries in all animals. The lysosomal acid PRL proteolytic activity and the lysosomal enzyme activities, N-acetyl-beta-glucosaminidase and beta-glucuronidase, were increased by suckling withdrawal alone. Acid PRL proteolytic activity was further increased (to 18-fold) by coadministration of bromocriptine, whereas the increase in the activities of the other lysosomal marker enzymes was blocked. Malate dehydrogenase activity (mitochondria) was also increased by litter removal and blocked by bromocriptine. The activity of the plasma membrane markers 5'-nucleotidase and alkaline phosphatase were increased by litter removal, and bromocriptine further increased both enzyme activities. The activity of neutral-alpha-glucosidase (endoplasmic reticulum) was unchanged by any treatment. The results demonstrate that bromocriptine produces significant changes in the activities of lysosomal marker enzymes, particularly acid PRL proteolytic activity, as well as marker enzymes of plasma membranes and other organelles in pituitaries of lactating and postlactating rats.
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PMID:Effects of bromocriptine on pituitary organelle marker enzyme activities in lactating and postlactating rats: selective activation of lysosomal prolactin proteolytic activity. 608 93

Analytical subcellular fractionation of tissue whole homogenates and microanalysis of organelle marker enzymes were used to study the activity and subcellular localization of enzymes implicated in HCO3 secretion in rat duodenal and gastric antral mucosae. The following organelles, characterized by their marker enzymes, were located in the density gradients: cytosol (lactate dehydrogenase), plasma membrane (5'-nucleotidase), peroxisomes (catalase), mitochondria (succinate dehydrogenase), endoplasmic reticulum (Tris-resistant alpha-glucosidase), lysosomes (N-beta-acetylglucosaminidase), and brush-border membrane (Zn2+-resistant alpha-glucosidase and alkaline phosphatase). Compared with gastric antrum, rat duodenal mucosa contained over twice the activity of HCO3-ATPase and of Na+-K+-ATPase but less than one-tenth the activity of carbonic anhydrase. Duodenal HCO3-ATPase activity was observed in both mitochondrial and brush-border membrane fractions, whereas antral HCO3-ATPase activity was confined to mitochondria. Na+-K+-ATPase activity was found largely in the basolateral membrane (duodenum) and plasma membrane (antrum). In both tissues carbonic anhydrase activity was localized to the cytosolic fraction. These observations offer further evidence that differing biochemical mechanisms underlie HCO3 secretion by gastric and duodenal epithelia.
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PMID:Activities and subcellular localizations of enzymes implicated in gastroduodenal bicarbonate secretion. 608 73

1. Analytical subcellular fractionation techniques have been applied to endoscopic human rectal biopsies to study the localization of enteroglucagon, somatostatin, vasoactive intestinal peptide and the properties of the principal subcellular organelles. 2. The peptide hormones, detected by radioimmunoassay, showed particulate localizations with single peaks in the density gradients for enteroglucagon (modal density 1.25) and somatostatin (modal density 1.23). Vasoactive intestinal peptide showed a less discrete localization but demonstrated a major peak (modal density, 1.17) with a small subsidiary peak (modal density 1.24). 3. The following organelles, characterized by their marker enzymes, were located in the density gradients; plasma membrane (5'-nucleotidase), mitochondria (malate dehydrogenase), peroxisomes (catalase), lysosomes (beta-N-acetyl-D-glucosaminidase), endoplasmic reticulum (neutral alpha-D-glucosidase) and cytosol (lactate dehydrogenase). 4. This technique can be used to investigate disease of the human rectum at a subcellular level.
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PMID:Subcellular fractionation studies of human rectal mucosa: localization of the mucosal peptide hormones. 610 76

Human lymphocytes were isolated from defibrinated blood by Ficoll-Hypaque centrifugation with erythrocyte hypotonic lysis. Homogenates of mixed lymphocytes were subjected to analytical subcellular fractionation by sucrose gradient centrifugation in a Beaufay automatic zonal rotor. The principal organelles were characterized by their marker enzymes: cytosol (lactate dehydrogenase), plasma membrane (5'-nucleotidase), endoplasmic reticulum (neutral alpha-glucosidase), mitochondria (malate dehydrogenase), lysosomes (N-acetyl-beta-glucosaminidase), peroxisomes (catalase). gamma-Glutamyl transferase was exclusively localized to the plasma membrane. Leucine amino-peptidase, especially when assayed in the presence of Co2+, was also partially localized to the plasma membrane. Experiments with diazotized sulphanilic acid, a non-permeant enzyme inhibitor, showed that these plasma membrane enzymes are present on the cell surface. No detectable alkaline phosphatase was found in the lymphocytes. Acid phosphatase and beta-glucuronidase were localized to lysosomes and there was some evidence for lysosomal heterogeneity. Leucine amino peptidase, optimal at pH 8.0, showed a partial localization to intracellular vesicles, possibly lysosomes, especially when assayed in the presence of EDTA. These studies provide a technique for determining the intracellular distribution of hitherto unassigned lymphocyte constituents and serve as a basis for investigating the cell pathology of lymphocytic disorders.
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PMID:Enzyme analysis and subcellular fractionation of human peripheral blood lymphocytes with special reference to the localization of putative plasma membrane enzymes. 614 55

Circulating non-T lymphocytes had higher activities of 5'nucleotidase (plasma membrane), neutral alpha-glucosidase (endoplasmic reticulum) and basal leucine amino-peptidase than did T lymphocytes. Activities of catalase (peroxisomes), malate dehydrogenase (mitochondria), lactate dehydrogenase (cytosol) and N-acetyl-beta-glucosaminidase, beta-glucuronidase and acid phosphatase (lysosomes), were similar in the lymphocyte subfractions. Lymphocyte 5'nucleotidase (plasma membrane) in patients with common variable hypogammaglobulinaemia is much lower than normal. However, the decrease is less marked in X-linked hypogammaglobulinaemia, chronic lymphatic leukaemia or protein loosing enteropathy or in lymphocytes isolated from cord blood. Cells from patients with nephrotic syndrome had normal levels of 5'nucleotidase. Other plasma membrane marker enzymes (gamma-glutamyl transferase, leucine amino-peptidase) were normal in lymphocytes from patients with common variable hypogammaglobulinaemia. There is a selective reduction of mitochondrial (malate dehydrogenase) and cytosolic (lactate dehydrogenase) enzymes, with normal activities of lysosomal, peroxisomal and endoplasmic reticulum enzymes, in patients with common variable hypogammaglobulinaemia. The lymphocyte subcellular organelles in normal subjects and patients with common variable hypogammaglobulinaemia have similar properties on sucrose density gradient centrifugation. It is suggested that lymphocytes from patients with common variable hypogammaglobulinaemia show a specific enzymopathy and that this is not simply a reflection of cellular immaturity.
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PMID:Lymphocyte enzyme activities in immunodeficiency syndromes with particular reference to common variable hypogammaglobulinaemia. 630 45

Four Capnocytophaga strains from blood cultures of immunocompromised patients with malignant disease and the type strains of three Capnocytophaga species were examined and compared to strains representing five other genera that are hard to differentiate from Capnocytophaga. With three rapid identification methods, negative catalase and oxidase reactions and positive ONPG assay, Capnocytophaga was easily separated from Eikenella corrodens, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, and CDC group DF-2. Haemophilus aphrophilus was excluded by leucine, valine and cystine arylamidase and alpha-glucosidase reactions (API ZYM). Further confirmatory reactions constituted gelatin hydrolysis, haemin requirement, and carbohydrate and esculin breakdown. Although rapid identification of Capnocytophaga to the genus level was feasible, differentiation on a species level proved impossible.
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PMID:Rapid identification of Capnocytophaga isolated from septicemic patients. 646 67

Rectal biopsy specimens from control subjects, patients with either active or quiescent ulcerative colitis, and patients with Crohn's colitis were examined histologically and assayed for marker enzymes associated with tissue organelles. They were catalase (peroxisome); neutral alpha-glucosidase (endoplasmic reticulum); alkaline phosphatase (plasma membrane); malate dehydrogenase (mitochondria); lactate dehydrogenase (cytosol). There was no significant change in these enzyme activities in patient samples compared with controls. Activities of three acid hydrolases (lysosomal enzymes), beta-glucuronidase, acid phosphatase, and N-acetyl-beta-glucosaminidase, were also assayed in the biopsy samples. Decreased activities of all three enzymes were noted in ulcerative colitis, particularly in active disease. Normal values were obtained in Crohn's colitis. Measurement of lysosomal integrity by assays of latent N-acetyl-beta-glucosaminidase activity revealed similar results in control and colitic subjects. It is suggested that the lysosomal changes reflect a specific tissue release of enzyme and may be implicated in the pathogenesis of the tissue damage.
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PMID:Organelle pathology in ulcerative and Crohn's colitis with special reference to the lysosomal alterations. 671 88

A total of 60 isolates of Haemophilus spp. from chickens, including four reference strains of H. paragallinarum and one of H. avium, were examined for their physiological and biochemical properties. The isolates could be placed into two groups. One group was identified as H. paragallinarum and consisted of 43 isolates including the four reference strains of H. paragallinarum. The other group was identified as H. avium and consisted of 17 isolates including the reference strain of H. avium. H. avium can be differentiated from H. paragallinarum by its possession of the enzymes catalase and alpha-glucosidase, capacity to grow in air, production of acid from galactose, and by the fact that its growth is not improved by the addition of chicken serum. In addition, the majority of H. avium isolates, unlike H. paragallinarum, possess a yellow pigment and produce acid from trehalose.
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PMID:Further characterization of Haemophilus paragallinarum and Haemophilus avium. 675 14

1. To establish the speed on onset of jejunal and ileal mucosal hypoplasia and hypofunction in parenterally fed rats, we measured three indices of mucosal mass, three mucosal enzymes and quantitative histology after 3, 6, 10 and 15 days of total parenteral nutrition and compared the results with those in two orally fed control groups, one with and one without intravenous catheters and metabolic cage restraint. The kinetics of galactose absorption in vivo were also measured after 10 days of total parenteral nutrition and in both control groups. 2. The most striking decrease in both jejunal and ileal mucosal wet weight and protein and DNA content per 10 cm length of intestine, occurred after only 3 days of total parenteral nutrition; thereafter the mean values showed only a slight further decrease. 3. The results of the morphometric studies showed that the hypoplasia affected the villi slightly more than the crypts. Within 3 days of starting total parenteral nutrition, mean jejunal mucosal thickness decreased by 16% and after 15 days it had fallen by 28%. The ileum showed similar, although less marked, changes. In the jejunum (not the ileum) modest cellular hypotrophy accompanied the mucosal hypoplasia; there were more epithelial cells/unit length of mid-villus and there was more DNA per g of mucosa in the total parenteral nutrition group than in the control group of rats. 4. Jejunal galactose absorption from the 16, 32 and 64 mmol/l solutions was significantly less in the 10-day total parenteral nutrition rats than in the controls, the apparent Vmax. being five times greater in the orally fed animals. The apparent Michaelis constant (Km) was also significantly less than normal in the jejunum of the parenterally fed rats, suggesting increased affinity of the hypothetical carrier for galactose, perhaps as a result of functionally hypermature cells. 5. Mucosal alkaline phosphatase and catalase activities per unit length of intestine decreased and alpha-D-glucosidase activity increased in the jejunum and ileum of the total parenteral nutrition rats. 6. These results show that during total parenteral nutrition, the ileum and particularly the jejunum show marked reductions in mucosal mass and function after only 3 days of total parenteral nutrition and that there is a more gradual and progressive loss of mucosal mass thereafter up to 15 days.
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PMID:Speed of onset of adaptive mucosal hypoplasia and hypofunction in the intestine of parenterally fed rats. 677 59

Different tests for the identification of Gardnerella (Haemophilus) vaginalis and for its differentiation from catalase-negative unclassified coryneforms from the vagina were evaluated on over 200 bacterial strains, with special emphasis on optimal test conditions. A presumptive identification of G. vaginalis in the clinical laboratory can be made on the basis of colonial morphology, clear beta-hemolysis with diffuse edges on human blood bilayer-Tween agar, a negative catalase test, and typical cell morphology in the Gram stain. This procedure will correctly identify 90 to 98% of suspect colonies of G. vaginalis with human blood bilayer-Tween agar as primary isolation medium. Useful additional reactions for the confirmation of G. vaginalis include positive hippurate and starch hydrolysis, positive alpha-glucosidase but negative beta-glucosidase tests, the production of acid from glucose and maltose but not from mannitol, and susceptibility to disks containing metronidazole, nitrofurantoin, sulfonamides, and bile.
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PMID:Identification of Gardnerella (Haemophilus) vaginalis. 682 Dec 5


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