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)

This study documented gastric fluid acidity in ambulatory surgical patients 30-120 min after they had taken a 300-mg tablet of ranitidine, as changes specific to this relatively brief dose-to-sampling interval previously had not been delineated. At 20-120 min before outpatient surgery, ranitidine was given with 15 mL of water to 112 ASA physical status I-III adults without increased risk factors for aspiration of acidic gastric contents. After induction of general endotracheal anesthesia, the gastric fluid was aspirated. Volume and pH were compared with a reference group (pH = 1.6 +/- 1; n = 161) that did not receive an H2-antagonist or water. Of 40 patients sampled at 30-60 min after dosing, 26 had pH greater than or equal to 2.5; mean pH was 3.9 +/- 2 (P less than 0.05 vs reference by Wilcoxon signed rank and chi 2 tests). Beyond 90 min, 28 of 28 patients had a pH greater than or equal to 2.5, with a mean of 6.3 +/- 1. No significant differences were noted with respect to mean gastric volume. We conclude that in patients without additional risk factors, oral ranitidine consistently prevents acid production when it is administered more than 90 min before induction of anesthesia.
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PMID:Time required for oral ranitidine to decrease gastric fluid acidity. 195 80

Proximal duodenum was perfused with various solutions and mucosal permeability assessed by measuring the clearance of 51Cr labelled ethylenediaminetetra-acetate (EDTA) from blood-to-intestinal lumen in anaesthetized rats. Net flux of fluid was determined by measurement of effluent weight changes. Perfusion of duodenum with 50 mM NaCl significantly increased fluid absorption but had no effect on EDTA clearance. EDTA clearance was unaffected by perfusion with 400 mM or 800 mM mannitol. Perfusion with 400 mM NaCl induced a sustained fluid secretion and a small but irregular increase (40%) in EDTA clearance. A significant 3.6-fold increase in clearance was obtained in response to perfusion of duodenum with deionized water. Similarly, perfusion with either 20 mM HCl or 50 mM ethyleneglycol-bis-(beta-amino-ethylether)-N,N'-tetraacetic acid (EGTA) significantly increased the EDTA clearance 3.3-fold and 2-fold respectively. Perfusion with a hypotonic HCl-solution (10 mM HCl + 40 mM NaCl) increased fluid absorption and the EDTA clearance. It is concluded that no positive linear relationship exists between luminal osmolality and 51Cr-EDTA movement across the mucosa. It is postulated that high luminal acidity or extreme hypotonicity increase the EDTA clearance by widening of and/or disruption of intercellular junctional structure.
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PMID:Characterization of 51Cr-EDTA as a marker of duodenal mucosal permeability. 195 98

The use of an easily measured physiological change as a method of detecting the effect of toxic mine effluent (acidity, heavy metals) on a standard aquatic test organism was examined. Changes in whole body sodium concentration of Pimephales promelas after exposure for eight hours to mine water in the field were assessed as a physiological indicator of acid and metal pollution from coal mines. Static 96-h lethality tests were also performed in the laboratory in water collected from severely acidic (pH 3.49), moderately acidic (pH 4.65) and circumneutral (pH 6.25) mine effluent impacted streams as well as an artificially prepared (reconstituted) water (RMW) at three similar pH's (but lacking potentially toxic metals). This allowed comparison of the two assays in their sensitivity and ability to detect interactions between heavy metals and acidity. Exposure of P. promelas to severely acidic mine water caused the same mortality as exposure to RMW, although in the latter the fish died more rapidly (2 vs. 3 h); moderately acidic water was more toxic than RMW lacking metals. No mortality was observed in circumneutral mine water or corresponding RMW. Toxicity as estimated by changes in whole body sodium levels of P. promelas followed a pattern similar to toxicity as determined by the 96-h lethality tests. Exposures of P. promelas to moderately acidic mine water at two pHs and trace metals concentrations resulted in significantly different body sodium concentrations and net sodium efflux between groups of fish within six hours. The results suggest that the whole body sodium assay is a useful indicator of coal mine pollution.
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PMID:Use of whole body sodium loss from the fathead minnow (Pimephales promelas) as an indicator of acid and metal toxicity. 195 81

Genetically diabetic mice (db/db) were given 50 mg/kg body weight/day substance L, a nontoxic basic amino acid and compared to control diabetic mice without treatment. The oral administration of the compound was started at the age of 3 months and the animals were sacrificed at the age of 7 months. No adverse effects were observed in animals given the substance L. Total food consumption, drinking water intake and body weight were comparable between the groups. Nonenzymatic glycosylation of serum proteins and hemoglobin was not significantly different in the groups. Renal pathological lesions in the control diabetic mice showed glomerular mesangial expansion and on electron microscopy thickened glomerular basement membranes with a mean thickness of 3,204 +/- 186 A. Treated animals showed significantly less mesangial crescents and thinner glomerular basement membrane thickness of 2,520 +/- 252 A (p less than 0.01). The experimental animals showed in addition a lower mean kidney weight. Glomerular but not tubular proteinuria was reduced in the treated group. Basement membrane collagen type IV isolated from kidneys of experimental animals was more soluble in acidity and showed a lower degree of cross-linking as evaluated by SDS-polyacrylamide gel electrophoresis. We conclude that substance L is beneficial to diabetic renal changes. We suggest that this positive effect could be due to the inhibition of glucose-mediated abnormal cross-linking of collagenous structures by the interaction of substance L with reactive carbonyl residues of glycosylation adducts of collagen. Other possible mechanisms are discussed.
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PMID:The effect of substance L on glucose-mediated cross-links of collagen in the diabetic db/db mouse. 207 11

Early changes in the morphology of the gastric mucosa after the skin had been burned were studied using a standardised model in rats. A full thickness burn was inflicted by exposing about 20% of the total body surface area to hot water (99 degrees C) for 10 s. Intragastric acidity was kept at pH 1.0 or pH 7.4 in six experimental groups of eight rats. Rats were subjected to burns with the stomach irrigated at pH 1.0 or pH 7.4. Parallel groups received fluid replacement with a solution of human albumin, and two uninjured groups served as controls. Lesions of the gastric mucosa were measured by planimetry of photographs, and light microscopy was used for histological examination. At an intragastric pH of 1.0, the burned rats developed mucosal erosions covering an average of 13% of the total glandular mucosa; the remaining groups had only minimal mucosal lesions. Erosions of the gastric mucosa after the skin had been burned could be prevented in two ways--either by establishing an alkaline (pH 7.4) milieu in the gastric lumen, or by replacing sufficient fluid to maintain aortic blood pressure at the pre-experiment level. Fluid replacement prevented mucosal erosions even if the intragastric pH was kept at 1.0. Thus both luminal acidity and local tissue blood flow are possible mechanisms for gastric epithelial damage following burns of the skin.
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PMID:Acute erosions of the gastric mucosa in burned rats: effect of gastric acidity and fluid replacement. 214 2

Reactions of cis-diamminedichloroplatinum(II) with phosphonoformic acid (PFA), phosphonoacetic acid (PAA), and methylenediphosphonic acid (MDP) yield various phosphonatoplatinum(II) chelates which were characterized by phosphorus-31 NMR spectroscopy. The P-31 resonances for the chelates appear at 6-12 ppm downfield as compared to the uncomplexed ligands. All complexes exhibit monoprotic acidic behavior in the pH range 2-10. The chemical shift-pH profiles yielded acidity constants, 1.0 x 10(-4), 1.5 x 10(-4), and 1.3 x 10(-6) M-1, for the PFA, PAA, and MDP chelates. In addition to the monomeric chelate, MDP formed a bridged diplatinum(II,II) complex when it reacted with cis-Pt (NH3)2(H2O)2(2)+. The P-31 resonance for this binuclear complex appears at 22 ppm downfield from the unreacted ligand. Rate data for the complexation reactions of the phosphonate ligands with the dichloroplatinum complex are consistent with a mechanism in which a monodentate complex is formed initially through rate-limiting aquation process of the platinum complex, followed by a rapid chelation. For the PFA and PAA complexes, initial binding sites are the carboxylato oxygens. Implications of the various binding modes of the phosphonates in relationship to their antiviral activities are discussed.
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PMID:Phosphonato complexes of platinum(II): kinetics of formation and phosphorus-31 NMR characterization studies. 215 Aug 56

The effect of bilateral vasectomy on in situ pH in seminiferous tubules, initial segments, proximal caput, middle corpus and proximal cauda epididymides of the rat has been studied employing in vivo microelectrode techniques. After bilateral vasectomy of four weeks duration, a significant increase in acidity of luminal fluid in the initial segments of the caput epididymides was observed. By eight weeks post vasectomy, luminal pH in the initial segments was significantly more acid as compared to sham-operated control animals or four weeks vasectomy while, in contrast, luminal pH in the proximal cauda epididymides was significantly more alkaline. The alteration of luminal fluid pH in the initial segments and proximal cauda epididymides after bilateral vasectomy may be the result of impairment of acid-base, as well as water transport pathways.
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PMID:Effect of vasectomy on in situ pH in rat testis and epididymis. 227 86

The paper presents pilot experience with oral use of sodium chloride mineral water Makov I for chronic achlorhydric gastritis. Altogether 734 patients were studied. Of them, 217 were evaluated for intragastric pH upon administration of a single water dose, 32 upon a course of treatment. There was a significant stimulating effect of the mineral water on gastric acidity.
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PMID:[The therapeutic efficacy of a sodium chloride mineral water in chronic gastritis patients with secretory insufficiency]. 228 13

We analysed sputum properties based on certain clinical information such as sputum volume, its gross appearance, the diagnosis, and difficulty in expectoration. We also compared sputum properties, clinical information and the effects of inhalation drugs on sputum in vitro, and on this basis evaluated the indications and limitations of inhalation therapy. It appears that inhalation therapy is limited by sputum properties, because the properties of large amounts of sputum, purulent sputum, and sputum expectorated with great difficulty are apparently different from those of other types of sputum. The effect of inhalation drugs on sputum was studied in vitro. Distilled water and normal saline showed as mucolytic agents. Bromhexine was acids in solution. The acidity caused the sputum to gel and reduced its mucolytic effect. Tyloxapole was alkaline in solution. The alkalinity decreased the mucociliary transport rate (MTR). Acetylcysteine had a marked mucolytic effect and decreased the MTR. There was a particular desire to develop drugs which improved MTR, because MTR is impaired by large amounts of sputum and sputum expectorated with great difficulty as well as in the case of sputum from diffuse panbronchiolitis patients.
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PMID:[Expectoration and inhalation therapy]. 229 Feb 25

Kock continent ileal reservoir for urinary diversion was performed in 53 patients with invasive bladder cancer (52) or neurogenic bladder (1). The postoperative follow-up period was from six to thirty-nine months. The clinical results showed no metabolic disturbance of blood electrolytes or acidity. Prolapse of efferent nipple valve developed in 4 patients (7.6%); and 2 underwent revisional surgery with a good result. Another 4 patients (7.6%) suffered from poor continence and relatively frequent catheterization to empty the pouch was necessary to prevent urine leakage through the stoma. Urodynamic study of the Kock pouch in these 4 patients showed a short functional nipple valve length and small pouch capacity. The other 45 patients (84.8%) had good continence. Urodynamic study of the pouch in 20 patients showed low pressure (mean of 13.3 cm H2O) in the pouch and high pressure (mean of 72.1 cm H2O) at the efferent nipple valve. Three patients had unilateral hydronephrosis in the follow-up intravenous urography. Corrective surgery for stenosis at the right ureteroileal anastomosis was done in 1 patient with normalization of the upper urinary tract afterward. The other 2 patients were managed by close observation for the mild hydronephrosis. Symptomatic bacteriuria developed in only 3 patients (5.7%) and responded well to antibiotic management. Reservoirography demonstrated no reflux into the upper urinary tract in all the follow-up patients. There was no significant change of the renal function at twenty-four months after operation detected by radionuclide (131I-Hippuran) renal functional study. All patients were satisfied with Kock urinary diversion.
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PMID:Clinical experience of Kock pouch continent urinary diversion. 232 24


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