Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum enzymes have not proved useful in evaluation of patients with early colon cancer, but certain enzymes such as transpeptidase, phosphohexone isosomerase, or 5'-nucleotidase have been of assistance in following the course of the disease, particularly in patients with metastatic spread to the liver. Attempts have been made to improve the utility of enzyme analysis in colon cancer by examination of enzyme patterns in colon biopsy specimens, feces, and colon washings. These studies, which will be summarized, are of importance in the possible development of diagnostic tools and as probes in the understanding of the etiology of colon cancer. The technical problems in carrying out these assays in humans, as well as the significance of the activity of aryl sulfatase, beta-glucuronidase, beta-glucosidase, lactic dehydrogenase, glucose-6-p-osphate dehydrogenase, and other enzymes will be considered.
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PMID:Enzymes in colon cancer. General information. 76 57

Gastric mucosal PG E2 receptors are the common antisecretory working point of all prostanoid types and may also be involved in "protective" effects. We investigated the subcellular localization of these receptors, as measured by displaceable 3H-PG E2 binding, and identified different organelles by monitoring the activities of specific marker enzymes. Porcine mucosal homogenates were subdivided by differential centrifugation into fractions P1 (1000 x g), P2 (20,000 x g), P3 (300,000 x g) and the supernatant S1. P3 was further fractionated over a series of sucrose step gradients. Mitochondria and lysosomes were enriched in P2 (maximum specific activities of cytochrome-c-oxidase of beta-glucosidase, beta-glucuronidase, beta-galactosidase, respectively). Plasma membranes (alkaline phosphatase, gamma-glutamyl-transpeptidase, 5-nucleotidase), tubulovesicles (H+/K(+)-ATPase) and rough endoplasmic reticulum (NADPH-cytochrome-c-reductase) were mainly found in P3, which also contained the majority of 3H-PG E2 binding sites. In contrast, prostanoid binding was barely detectable in S1. Density fractionation of P3 revealed that 3H-PG E2 binding sites shared a similar sedimentation profile with plasma membranes and tubulovesicular markers. No or negative correlation was found with lysosomes, rough endoplasmic reticulum and mitochondria. We conclude that mucosal PG E2 receptors are predominantly located at the cell surface. This supports the view that prostanoids inhibit gastric secretion through membrane receptors, but gives no clue for intracellular "protective" working points.
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PMID:Subcellular localization of prostaglandin E2 receptors in the gastric mucosa. 134 83

Recently, some knowledge of metabolic pathways, rather than individual enzyme activities of M. leprae, is becoming available. Ultimately this may be useful in devising culture media for M. leprae. Knowledge restricted to individual reactions may be misleading. For instance, the detection of GlcNacase and beta-glucuronidase and the subcellular localization of hyaluronic acid led to attempts to cultivate M. leprae on hyaluronic-acid based medium. Subsequent investigations suggested that there was no pathway for the breakdown of hyaluronic acid in M. leprae. The biochemical pathways for breaking down glucose and glycerol seem to be complete, and thus similar to many bacteria, but there is an unusually high level of one enzyme, 6-phosphogluconate dehydrogenase (6PGDH). Although 6-phosphogluconate is oxidized by M. leprae, and this is an unusual activity, reflecting very high levels of 6PGDH, glycerol may be a preferable energy source (on the basis of rates of oxidation by suspensions) for M. leprae in attempts to cultivate the bacterium. The utilization of 6-phosphogluconate might be important for other aspects of M. leprae metabolism not yet investigated (e.g., pentose metabolism) or it may be an adaption, not needed in vitro, to its existence in host macrophages. Alternatively, its oxidation may be a way of rapidly generating NADPH at critical times for the bacterium. Other unusual activities which have been reported are the presence of an enzyme characteristic of chemoautotrophism , completely surprising in view of the biology of M. leprae. This report needs to be confirmed--some aspects, in fact, have failed to be confirmed. o-Diphenoloxidase activity is unique, among mycobacteria, to M. leprae, but there is still doubt over whether or not it is an enzymatic activity and its function is unknown. A transpeptidase which may be involved in cell wall synthesis, recently demonstrated in M. leprae, is a typical mycobacterial enzyme. It is now known that iron could be supplied to M. leprae in potential media in the form of ferriexochelin from M. neoaurum . Two "deletions" in the metabolic processes of M. leprae have been observed. Catalase appears to be absent in M. leprae; its addition to media stimulates the growth of some organisms since peroxides form in the bacteriological media . Purine synthesis de novo occurred at a very low rate compared with purine scavenging. Whether this is an adaption to growth in vivo is not known.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Metabolism in Mycobacterium leprae: its relation to other research on M. leprae and to aspects of metabolism in other mycobacteria and intracellular parasites. 614 38

Renal toxicity of aminoglycosides seems to be less frequent in newborn infants compared to adults even though glomerular filtration rate and tubular secretion and reabsorption mechanisms are subjected to adaptive processes during the neonatal period. In 14 infants, kinetic parameters of gentamicin were determined using an open three-compartment body model. According to the lower glomerular filtration rate, the beta-elimination phase is longer in the newborn infant compared to adults, while the gamma-elimination phase is quite similar to adult values. The calculated drug accumulation in the deep compartment (kidney) under steady-state conditions is lower in newborns compared to infants. The excretion of urinary enzymes of tubular origin, that is the lysosomal NAG (N-acetyl-beta-D-glucosaminidase), beta-glucuronidase, and the brush-border-associated AAP (alanine-aminopeptidase), GGT (gamma-glutamyl-transpeptidase), are lower in healthy newborn infants compared to older ones. The increase of AAP, for instance, during aminoglycoside therapy is less pronounced in newborn infants, especially in prematures, if compared to adult values. After end of therapy the AAP excretion decreases to normal. The calculated rate of this decrease takes place in a fashion similar to the release of drugs from the kidney (gamma-elimination phase). The data indicate that there may be a lower renal accumulation of aminoglycosides in newborn infants, which can be explained by the morphometric and functional characteristics of the newborn kidney.
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PMID:Renal toxicity of aminoglycosides in the neonatal period. 614 23