Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. beta-d-Galactopyranosyl pyridinium salts are well-behaved substrates for the beta-galactosidase of Escherichia coli, catalysis occurring by the interaction of the salt itself with the normal active site of the protein. 2. logk(cat.) values for seven such salts show a linear relationship (correlation coefficient=-0.997) with the pK(a) of the parent pyridine. 3. The beta-d-galactopyranosyl derivatives of pyridine and 4-bromoisoquinoline exhibit alpha-deuterium kinetic isotope effects of 1.136+/-0.040 and 1.187+/-0.046 on their enzymic hydrolysis, indicating formation of a galactopyranosyl cation in the rate-limiting step. 4. This behaviour of the pyridinium salts contrasts with the behaviour of aryl galactosides and this contrast can be accommodated by the beta-galactosidase mechanism of Sinnott & Souchard (1973). 5. The alpha-deuterium kinetic isotope effect for the hydrolysis of beta-d-galactopyranosyl azide is 1.098+/-0.033; comparison of the k(cat.) value of the azide with that of a pyridinium salt of the same aglycone pK(a) enables a maximum factor of 70 to be ascribed to the acceleration of the departure of azide by intracomplex general acid catalysis. 6. The possibility of the rate-limiting process in the glycosidase-catalysed hydrolysis of aryl glycosides being a conformation change is considered for a number of glycosidases where correlations of k(cat.) with aglycone acidity, reported in the literature, have been unsuccessful.
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PMID:The beta-galactosidase-catalysed hydrolyses of beta-d-galactopyranosyl pyridium salts. Rate-limiting generation of an enzyme-bound galactopyranosyl cation in a process dependent only on aglycone acidity. 446 53

Following previous demonstration that isoproterenol stimulated and norepinephrine inhibited gastric acid secretion induced by secretagogues, role of adrenergic agonists was studied by measuring acidity the peptic activity of the effluent of the perfused rat stomach. Response of gastric secretion to isoproterenol was increased by theophylline treatment but was not affected by metiamide treatment. N6, O2'-Dibutyryladenosine 3', 5'-cyclic monophosphoric acid sodium salt monohydride (dibutyryl-c-AMP) stimulated gastric secretion in a dose-dependent manner. These results suggest the possibility that the action of isoproterenol in gastric acid secretion is mediated by c-AMP. However, gastric secretion induced by pentagastrin, histamine, or carbamylcholine was not affected by theophylline treatment. N2, O2'-Dibutyrylguanosine 3', 5'-cyclic monophosphoric acid sodium salt (dibutyryl-c-GMP) did not exert any effect on gastric secretion. Depression of pentagastrin-induced gastric secretion by norepinephrine was reversed by EGTA infusion. Moreover, Ca2+, depressed pentagastrin-induced gastric secretion. These results suggest that the action of norepinephrine is closely related to the concentration of Ca2+.
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PMID:Role of adrenergic agonists on gastric secretion in the rat. 611 Jul 14

The treatment of neuromuscular junctions with phosphomolybdic acid (PMA) and silicotungstic acid (STA) heteropolyanions permits the visualization of electron dense precipitates in the synaptic vesicles of the cholinergic motor nerve terminals. At the light microscopic level, the uncolored molybdenum salt is visualized after reduction to molybdenum blue. The blue coloration is confined to the nerve terminals. Since PMA and STA are known as strong precipitating agents of quaternary ammonium compounds (cations) it is supposed that they have insolubilized in situ the acetylcholine (Ach) of the synaptic vesicles by means of a rapid ionic interaction. Furthermore, in spite of the strong acidity of PMA and STA solutions, the ultrastructure of the treated tissue is not significantly altered but on the contrary seems to be well preserved. The ionic insolubilization of Ach, added to the good preservation of the ultrastructure prompted us to use the term "ionic fixation".
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PMID:Molybdic and tungstic heteropolyanions for "ionic fixation" of acetylcholine in cholinergic motor nerve terminals. 630 36

The effect of salt concentration, acidity, and storage temperature on the spore germination of Bacillus cereus and the growth rate of the organism was investigated. Increasing the amount of salt to more than 5% or acidifying the milk to pH 5.0 or 4.5 greatly affected the germination and growth of B. cereus spores. When a culture of Streptococcus lactis was used as an acidifying agent, B. cereus showed a normal growth rate during the first 12 h, followed by a sharpe reduction in numbers. When B. cereus spores were inoculated in reconstituted dry milk or baby food, a higher multiplication rate was obtained at 30 degrees C than at 8 degrees C.
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PMID:Factors affecting germination and growth of Bacillus cereus spores in milk. 642 77

Ten patients who underwent elective abdominal surgery were given a daily load of one liter of a 10% aminoacid solution randomly containing cationic aminoacid as clorure or acetate salt during the first four post-operative days. None of the patients developed acidosis but the mean daily urinary excretion of titratable acidity and ammonium ions was significantly higher in clorure treated patients. An aminoacid solution containing aminoacid as acetate acts as a sparing solution for tubular buffer activity, and therefore should be preferred for patients with tubular impairment.
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PMID:Acid load after intravenous aminoacid infusion: comparison of clorurated vs. acetated solutions. 646 53

The contamination with microorganisms (enterococci and coliforms) indicative of hygeinic status was studied in 98 samples of white brine cheese (33 samples of cow's milk cheese and 65 of ewe's milk cheese) prepared for sale. It was found that 22.4 per cent of the cheese samples do not contain enterococi in 0.01 g product but in 15.3 per cent their amount exceeds 100 000/g. No relationship was found between enterococci finding and cheese content of salt, titratable and active acidity. Cheese contamination with coliforms bacteria is limited--merely 3.1 per cent of the samples contain coliforms in quantity of 10--100/g. No difference was found in the contamination of cow's and ewe's milk white brine cheese with enterococci and coliforms. The enterococci microflora in white brine cheese and in the brine is represented predominantly by Str. faecium and Str. durans (91.3 per cent of the isolated strains). The coliforms are represented by E. coli, Enterob. aerogenes and Citrob. intermedium.
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PMID:[Enterococcal and coliform content in white brine cheese]. 677 84

The influence of carbenoxolone sodium on HCO-3 transport has been examined in spontaneously alkalinizing amphibian antral (Necturus and Rana catesbeiana) and proximal duodenal (Rana catesbeiana) mucosa and in cimetidine-treated fundic mucosa (Rana temporaria) in vivo. Low concentrations of carbenoxolone (10(-6)-10(-4) mol/l, serosal side and 10(-5) mol/l, luminal side) did not affect the secretory rate or electrical properties of these tissues. In the stomach a higher concentration of carbenoxolone (10(-3) mol/l, serosal side) caused an immediate fall in transmucosal potential difference (PD) and electrical resistance. There was an initial decrease in the rate of HCO-3 transport followed by an increase in titratable alkalinization due to passive permeation of base from the serosal bathing solution. The non-steroidal anti-inflammatory agent ibuprofen (3 x 10(-3) mol/l, serosal side) inhibited alkaline secretion while the bile salt sodium taurocholate (10(-4) mol/l, luminal side) converted net alkaline secretion to a titratable acidity in cimetidine-treated fundus. Pretreatment of the mucosa with carbenoxolone (10(-4) mol/l) did not influence the response to taurocholate but when added with ibuprofen it potentiated the inhibitory effect of this drug on fundic alkaline secretion. In contrast, prostaglandin E2 (10(-6) mol/l) markedly reduced the inhibition of fundic alkaline secretion caused by ibuprofen. The anti-ulcer properties of carbenoxolone do not appear to be related to effects on gastroduodenal HCO-3 transport.
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PMID:Effect of carbenoxolone on alkaline secretion by isolated amphibian gastric and duodenal mucosa. 680 Aug 23

Past studies of norepinephrine-stimulated protein phosphorylation in intact C-6 glioma cells had identified a 58,000 molecular weight, 5.7 isoelectric point protein (58K-5.7) as a cyclic AMP-dependent phosphoprotein and had shown that 58K-5.7 was one of the most abundant proteins of the nuclear fraction. Initial experiments of present studies showed that the 58K-5.7 protein remained with the nuclear ghost, or matrix structure, after removal of chromatin. Based on the size, acidity, abundance, nonsolubilization by nonionic detergent and salt, and solubilization by urea, the hypothesis was advanced that the 58K-5.7 protein was the vimentin-type intermediate filament protein. The hypothesis was tested by two types of immunochemical experiments. Antisera against hamster vimentin reacted selectively with only the 58K-5.7 protein in polyacrylamide gels of urea-solubilized cellular residues (i.e., nonionic detergent and 0.6 M salt-insoluble material) as determined by immunoautoradiography. Antisera against the pure 58K-5.7 protein of C-6 cells bound selectively to a fibrous array of cellular material typical of vimentin filaments as determined by indirect immunofluorescence. It is concluded that the 58K-5.7 protein is vimentin.
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PMID:Vimentin: a phosphoprotein under hormonal regulation. 702 79

A study was designed to determine the effects of substituting up to 50% of the NaCl in kimchi, a fermented Chinese cabbage (Brassica pekinensis) product containing scallions, garlic, ginger and hot red pepper powder, with KCl. Brine water (15% salt) used to soak cabbage contained NaCl:KCl ratios of 1:0 (control), 5:1, 2:1 and 1:1 (wt:wt). Total acidity and pH of kimchi reached acceptable ranges of 0.4-0.6% (as lactic acid) and 4.4-4.7, respectively, after 13 days of incubation at 13 +/- 1 degree C. Kimchi made using brine water containing 5:1 and 2:1 (NaCl:KCl) salt ratios was characterized by faster growth of lactic acid bacteria and total aerobic microorganisms compared to the control formulation. Sensory qualities (saltiness, bitterness, sourness, hotness and texture) of kimchi prepared from cabbage soaked in brine containing NaCl and KCl at all test ratios were judged to be acceptable.
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PMID:Fermentation and sensory characteristics of kimchi containing potassium chloride as a partial replacement for sodium chloride. 804 52

New procedures for the preservation stage of ripe olives from Hojiblanca cultivar were studied. An aerobic fermentative process was used with initial pH correction (0.3% acetic acid) and various NaCl concentrations: 6, 3 and 0% (w/v) in tap water. Treatments were carried out at industrial level and the spontaneous changes monitored. At initial salt concentrations of 6 and 3% (w/v) NaCl, pH rose progressively, reaching 4.3 at equilibrium maintaining during this period a constant free lactic acidity of around 0.4% (w/v). When the initial solution was tap waste, however, the pH decreased rapidly to stabilize at about 3.7, and lactic acidity increased continuously to reach values over 1% (w/v) at the end of the preservation process. In all treatments aeration effectively purged the carbon dioxide from the preservation brines, preventing shrivelling of olives. The microbial growth was strongly influenced by the initial NaCl concentration. At 6 and 3%, only yeasts grew, the most abundant being Pichia membranaefaciens, P. vini, P. fermentans and Hansenula polymorpha. However, when there was no NaCl, lactic acid bacteria colonized the solution. Lactobacillus plantarum and Pediococcus inopinatus were the only species found. In this case there was a co-existence between yeasts and lactic acid bacteria. As the treatment that supported lactic acid bacteria achieved the best final pH and acidity for olive stability, it may help to overcome the obstacles to a lactic fermentative process during the preservation stage of ripe olives from the Hojiblanca cultivar.
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PMID:Microflora of the aerobic preservation of directly brined green olives from Hojiblanca cultivar. 824


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