Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunochemical techniques with enzymes as the antigen have grown in frequency during the last few years. These techniques have allowed evaluation of enzymes in the presence of endogenous inhibitors. Among those enzymes measured by immunochemical techniques and which have found diagnostic application, mention will be made of alkaline phosphatase (with particular reference to the intestinal, placental, and Regan isoenzymes), lactate dehydrogenase (in which renewed interest has developed due to techniques for specifically measuring the LD-1 isoenzyme), aspartate aminotransferase (of which the cytosolic and mitochondrial forms can now be independently measured by immunochemical techniques), acid phosphatase (for which a specific immunochemical assay for the prostatic enzyme has been widely introduced in diagnostic laboratories), and creatine kinase (for which a variety of immunochemical techniques to measure the M- and B-subunits are now part of standard laboratory assays). Other enzymes which will be discussed in this review include phosphohexose isomerase, amylase, ribonuclease, and lysozyme (muramidase). Finally, the use of enzymes, particularly asparaginase, in the chemotherapy of cancer will be outlined.
 ...
PMID:Immunoassay of enzymes--an overview. 634 26

Administration of zinc (Zn) simultaneously with lead (Pb) into the chick egg yolk sac reduced the accumulation of Pb and Pb-induced alterations in the activities of acid phosphatase, beta-glucuronidase and ribonuclease in the brain of the embryo. The results suggest protection against toxic effects of Pb by Zn.
 ...
PMID:Effect of zinc on lead-induced changes in brain lysosomal enzymes in the chick embryo. 669 89

A pancreas-specific antigen was identified by immunologic techniques and purified from saline extract of human pancreas. The purified pancreas-specific antigen was shown to be homogeneous by polyacrylamide gel electrophoresis under both denaturing and non-denaturing conditions. It had a molecular weight of 44000 as estimated by gel filtration or sodium dodecyl sulfate-gel electrophoresis, and a sedimentation coefficient of 3.4 S as analyzed by sucrose gradient centrifugation. Pancreas-specific antigen possessed an isoelectric point of 4.9 and migrated to alpha-beta region upon immunoelectrophoresis. By colorimetric assay procedures, pancreas-specific antigen exhibited no enzyme activity, such as amylase, protease, esterase, lipase, acid phosphatase, alkaline phosphatase peroxidase, deoxyribonuclease or ribonuclease. Immunoreactivity of pancreas-specific antigen was sensitive to proteolytic enzymes, perchloric acid and high temperature (70 degrees C, 10 min); but insensitive to neuraminidase or beta-glucosidase. Immunohistochemical staining revealed that pancreas-specific antigen was located in acinar cells of human pancreas. In addition, a higher concentration of pancreas-specific antigen was detected in pancreatic juice than in the saline extract of pancreas. This newly identified pancreas-specific antigen, therefore, may be a useful marker protein in physiological studies of pancreas and pancreatic secretion.
 ...
PMID:Purification and characterization of a human pancreas-specific antigen. 678 69

Experiments on white male rats were made to study and compare the action of hormonal drugs (testosterone propionate, retabolil and chorionic gonadotropin) on lysosomal enzymes of different tissues. There were differences in the changes in the activity of acid phosphatase, ribonuclease, cathepsins and beta-galactosidase after a single administration of testosterone and after a course of drug treatment. Retabolil and chorionic gonadotropin acted on lysosomal enzymes of spermatic vesicles similarly to testosterone given in a single dose. As far as the activity of liver cathepsins and beta-galactosidase is concerned retabolil was found to produce an opposite effect as compared to that of testosterone.
 ...
PMID:[Effect of hormonal preparations on lysosome enzyme activity in rat tissues]. 686 93

Low dosages of chloramphenicol (25-50 micrograms/ml) brought about a 2-4-fold stimulation of acid phosphatase activity in 48 h-germinated cotton (Gossypium hirsutum) embryos. However, at high concentrations of chloramphenicol (100-1000 micrograms/ml), there was a progressive decline in enzyme activity. The stimulatory effect of the drug on acid phosphatase activity was relatively specific, since no significant stimulation of activities of proteinase, deoxyribonuclease, ribonuclease, o-diphenolase and peroxidase was observed in germinating cotton embryos. Chloramphenicol, however, did promote the activities of isocitric lyase and alkaline phosphatase. Sephadex G-200 chromatography of the enzyme fraction revealed high (230 000)- and low (106 000)-molecular-weight multiple forms of acid phosphatase in the chloramphenicol-treated embryos, in contrast with a single molecular form (mol.wt. 106 000) in the untreated embryos. Thus the treatment of cotton embryos with chloramphenicol induced both a qualitative and a quantitative change in the acid phosphatase activity. Chloramphenicol-stimulated acid phosphatase activity was strongly inhibited when Pi was included in the germination medium. However, the control embryos showed less pronounced inhibition of enzyme activity in presence of Pi ions.
 ...
PMID:Chloramphenicol stimulates acid phosphatase activity in germinating cotton (Gossypium hirsutum) embryos. 687 Aug 57

We have measured changes of pH in a protein's microenvironment consequent on its binding to the cell surface and incorporation into pinosomes. Changes of pH were measured from single, living cells and selected regions of cells by the fluorescence ratio technique using a photon-counting microspectrofluorimeter. The chemotactic agent and pinocytosis inducer, ribonuclease, labeled with fluorescein (FTC-RNase), adsorbed to the surface of Amoeba proteus, and was pinocytosed by cells in culture media at pH 7.0. The FTC-RNase entered an apparently acidic microenvironment, pH approximately 6.1, upon binding to the surface of amoebae. Once enclosed within pinosomes, this protein's microenvironment became steadily more acidic, reaching a minimum of pH approximately 5.6 in less than 10 min. FTC-RNase pinocytosed by the giant amoeba, Chaos carolinensis, entered pinosomes whose pH was correlated with their cytoplasmic location during the initial 30-40 min after pinocytosis. The majority of pinosomes containing FTC-RNase clustered in the tail ectoplasm of C. carolinensis during this interval and had a pH of approximately 6.5; those released into endoplasm and carried into the tip of cells had a pH below 5.0. As pinosomes became distributed at random in C. carolinensis (1-2 h after initial pinocytosis), differences in pH between tip and tail pinosomes vanished. We have also measured the pH within single phagosomes of A. proteus. Phagosomal pH dropped steadily to approximately 5.4 within 5 min after particle ingestion in 70% of the cells measured, and reached this level of acidity within 10 min in 90% of the cells measured. By contrast, stain for the lysosomal enzyme, acid phosphatase, was evident within only 20% of 5-min-old phagosomes visualized by light microscopy, and within only 40% of 10-min-old phagosomes. A microfluorimetric assay was used to simultaneously record changes in pH, and the initial deposition of lysosomal esterases, within phagosomes of single, living Amoeba proteus. Near complete acidification of the phagosome was recorded from some cells before phagosomal fusion was evident by this microfluorimetric assay. From other cells, however, continued acidification of phagosomes was recorded after lysosomal fusion was initiated. We conclude that acidification of phagosomes by A. proteus is initiated but not necessarily completed prior to phagosome-lysosome formation, and that the two events are closely linked in time. Initial acidification of endosomes is a property intrinsic to the plasma membrane which envelops particles at the cell surface, rather than the result of lysosomal fusion with phagosomes.
 ...
PMID:Acidification of phagosomes is initiated before lysosomal enzyme activity is detected. 688 16

An approximately 50-fold increase in serum beta-glucuronidase activity appeared 2 hours after the administration of such organophosphate insecticides as dichlorvs, diazinon and disulfoton and of a carbamate insecticide, carbaryl. The activities of other acid hydrolases in the serum such as ribonuclease, acid phosphatase, hyaluronidase and N-acetylglucosaminidase did not change significantly after the insecticide treatment. The response was related to the dose level and was evident after a single intraperitoneal dose of diazinon as low as 1.6 mg/kg. This appearence of an increase in beta-glucuronidase was retarded by pretreatment with SKF 525A, an inhibitor of drug metabolizing enzyme. When beta-glucuronidase was elevated by a large dose of diazinon, full response to a second dose of diazinon did not occur until approximately one month after administration of the first dose.
 ...
PMID:Increase of beta-glucuronidase activity in the serum of rats administered organophosphate and carbamate insecticides. 726 27

The large protein bodies of the storage parenchyma cells of mung bean (Vigna radiata) cotyledons contain vesicles measuring 0.2 to 2.0 mum in diameter. The vesicles contain ribosomes, ribosomes, membranous elements which may be derived from the endoplasmic reticulum and occasionally Golgi bodies and mitochondria. The vesicles can be seen by transmission electron microscopy in thin sections of plastic embedded specimens and in replicas of freeze-fractured preparations. Serial sections show that the vesicles are completely separated from the protein body membrane and are not invaginations of that membrane. Vesicles with cytoplasmic structures are seen most frequently in 2 to 4 day old seedlings. The vesicles may be formed when undulations of the protein body membrane are so deep as to permit the pinching-off of a portion of the cytoplasm, resulting in its subsequent isolation from the cytoplasm within the protein body. The digestion of the storage protein in the protein body is accompanied by the disappearance of the ribosomes and the membranous elements in the vesicles. We interpret this disappearance of the cytoplasmic structures in the vesicles as being due to their digestion by the protein body hydrolases (ribonuclease, proteinase and lipolytic enzymes). The uptake of cytoplasmic structures by the protein bodies continues after the reverse proteins have been digested. Cytochemical staining shows that the protein bodies and especially the vesicles are rich in acid phosphatase, a known marker of lytic activity in cells. The evidence presented here indicates that the protein bodies are the intracellular sites at which the digestion of cytoplasmic structure occurs. Protein bodies should therefore be considered not only as compartments for the hydrolysis of the stored protein, but also as autophagic organelles involved in the degradation of cytoplasmic macromolecules. The term protein bodies is well established, but the term protein storage vacuoles may describe these organelles more precisely.
 ...
PMID:Uptake and apparent digestion of cytoplasmic organelles by protein bodies (protein storage vacuoles) in mung bean cotyledons. 728 40

The effect of a low protein (4%) diet on the activity of the hydrolytic enzymes ribonuclease, deoxyribonuclease, acid and alkaline phosphatases, beta-glucuronidase and lysozyme has been studied in the spleen and thymus of weanling Wistar rats. Experimentation was carried out over 20 and 30 days, and comparisons were made with well-nourished (12% protein) controls. Body weight decreased during the terminal period in protein-deficient animals (P less than 0.001). Spleen and thymus absolute net weights also dropped significantly (P less than 0.001). In terms of organ weight relative to body weight, there was a clear decrease in thymus compared with controls (P less than 0.001). Enzyme activities expressed per total organ fell significantly. Thus, in spleen at 20 days the decrease was maximum in ribonuclease activity (91.15%) and minimum in acid phosphatase activity (44.09%). Thymus decreases ranged from 83.60% activity in beta-glucuronidase and 93.56% in ribonuclease. At 30 days decreases were accentuated; the maximum value in spleen was 92.34% lysozyme and, in thymus, 97.09% acid phosphatase. A large increase in hydrolytic activity expressed per milligram of protein was registered, especially at 30 days. This increase reached a maximum of 78.08% beta-glucuronidase in thymus and a minimum of 56.1% alkaline phosphatase; acid phosphatase and ribonuclease activities were not modified. In spleen, however, acid phosphatase (34.00%), alkaline phosphatase (62.50%), deoxyribonuclease (39.25%), and beta-glucuronidase (36.01%) increased, but lysozyme and ribonuclease enzymes decreased. We concluded that a low protein diet increases catabolism in spleen and thymus through an enhancement of lysosomal hydrolase activities.
 ...
PMID:Effect of protein deficiency on the lysosomal enzyme activities of the spleen and thymus of weanling rats. 731 May 38

Chromium (Cr) at graded levels when added in sand culture of wheat (T. aestivum L. cv. UP2003) under glasshouse conditions resulted in reduction in biomass, chlorophyll and activities of catalase and peroxidase while enhanced acid phosphatase and ribonuclease activities. Elevated levels of Cr supply significantly reduced the concentration of inorganic phosphorus. With an increase in Cr supply the uptake of chromium also increased significantly in different plant parts especially in roots. Above metabolic lesions due to Cr in wheat provided evidence that the element in nutrient medium if present in excess may be inhibitory to plant growth and development.
 ...
PMID:Chromium uptake and toxicity effects on growth and metabolic activities in wheat, Triticum aestivum L. cv. UP 2003. 897 7


<< Previous 1 2 3 4 5 Next >>