Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The metabolic response of the rat liver to flushing and reflushing with Marshall's solution at pH 7.2 or pH 7.8 has been studied by 31P nuclear magnetic resonance spectroscopy. The changes in intracellular pH, inorganic phosphate, ATP and phosphomonoesters have been determined from the 31P spectra. We show that the intracellular pH at any stage of the flushing protocol is largely independent of the pH of the medium when using these solutions. However, we demonstrate that there are differences between the efficiency of the two solutions in respect of the rates of hydrolysis of ATP and accumulation of phosphomonoesters. There were also differences in the response of the livers upon reflushing--those livers reflushed at pH 7.2 resynthesized ATP from a lower initial concentration to achieve ATP concentrations similar to those restored in livers reflushed at pH 7.8. These trends were mirrored in the responses of the phosphomonoester peaks (which contain a contribution from AMP). We conclude that short-term control of liver metabolism during hypothermia is possible by use of solutions of different pH, but that for longer-term storage, other approaches may be necessary to maintain metabolic integrity.
 ...
PMID:Biochemical consequences of reflushing hypothermically-stored liver with fresh cold perfusate. Studies on rat liver using 31P NMR spectroscopy. 264 Dec 99

Nuclear magnetic resonance (NMR) spectroscopy was used in the study of rat livers following flushing with a clinically used preservation solution containing either 12 or 30% (v/v) Me2SO. The extent of equilibration of Me2SO in the tissue after 10-15 min of perfusion with Me2SO and again after subsequent washout with Me2SO-free medium was assessed by 1H NMR spectroscopy. 31P NMR spectroscopy was used to follow the changes in ATP, ADP, inorganic phosphate, and tissue pH. The data show that 1H NMR spectroscopy can be used as a sensitive and rapid method of assessing the equilibration and concentration of compounds such as Me2SO, since these compounds are likely to be present at concentrations greatly in excess of other constituents of the medium and will therefore give rise to strong, easily detected signals. At the same time, 31P NMR spectroscopy can be used to monitor the metabolic status of the tissue reflected in the levels of ATP, ADP, and inorganic phosphate, as well as being a noninvasive monitor of intracellular pH. The possibility of determining the tissue pH in the presence of solutes such as Me2SO is discussed.
 ...
PMID:Studies on cryoprotectant equilibration in the intact rat liver using nuclear magnetic resonance spectroscopy: a noninvasive method to assess distribution of dimethyl sulfoxide in tissues. 270 27

The purpose of this study was to evaluate the value of additive components and colloid included in the University of Wisconsin (UW) solution. Therefore, this solution was compared with a solution consisting of the basic components of the UW solution (potassium lactobionate, raffinose, phosphate buffer and MgSO4). We employed a method of measuring the amount of chromium-51-labeled erythrocyte trapped in the medullary vasculature 20 min after reperfusion of kidney grafts cold-stored for 24-48 h in either the basic UW (bUW) or the original UW (oUW) solution. The amount of trapping has been shown to correlate well with the degree of cold ischemic injury. Both hemodiluted (hct 20-27%) and normal (hct 41-45%) recipients were used. Long-term viability of grafts stored in either bUW or oUW was investigated in survival experiments and the flow rates during in situ flush-out were also measured, as well as weight changes during the storage period. The results showed no significant difference between the two solutions, regardless of ischemia time or whether hemodiluted or normal recipients were used. However, the flow rate and weight measurements showed that flushing was more rapid and kidney swelling less pronounced using oUW. Survival rates in long-term transplantation experiments were similar. It was concluded that the inclusion of a colloid improves the rheological properties of the UW solution and that the additives besides the basic components did not offer any advantage.
 ...
PMID:Relevance of additive components of University of Wisconsin cold-storage solution. An experimental study in the rat. 278 5

The composition of a precipitate obtained from a silastic right atrial catheter was determined. The precipitate was collected and washed with deionized water thoroughly before subjecting portions of it to organic and inorganic analysis. Inorganic analysis was conducted using scanning electron microscopy and x-ray spectroscopy for sodium, aluminum, silicone, sulfur, chlorine, and calcium. Phosphorus analysis was conducted by a commercial laboratory. Organic analysis was conducted by thin layer chromatography with cholesterol, phosphatidyl serine, phosphatidyl choline, phosphatidyl ethanolamine, and sphingomyelin as standards. Silicone, calcium, and phosphorus and three organic compounds, which could not be conclusively identified, were found. The precipitate was most likely calcium phosphate intermixed with silicone oil lubricant and residual total parenteral nutrition (TPN) solution. This formed in the catheter at body temperature probably due to incomplete catheter flushing.
 ...
PMID:Precipitate analysis from an indwelling total parenteral nutrition catheter. 312 64

The isolated perfused rabbit liver model has been used to determine the essential components of the UW solution for hepatic preservation by simple cold storage. Livers were stored on ice for 48 hr after initial flushing with the solution being tested, and then reperfused at 38 degrees C in an isolated perfusion circuit; bile flow and enzyme (SGOT, SGPT, and LDH) release during a 2-hr period were recorded. All solutions tested contained phosphate (25 mM) as a buffer and magnesium sulfate (5 mM). Sodium can be substituted for potassium without adverse effects. Lactobionate, raffinose and glutathione cannot be omitted; all other components can be eliminated without altering the effectiveness of the solution in this model.
 ...
PMID:An analysis of the components in UW solution using the isolated perfused rabbit liver. 317 57

The inhalation of platelet activating factor (PAF) produces bronchoconstriction in normal and asthmatic subjects. To identify the mechanism by which PAF-induced bronchoconstriction occurs in humans, bronchoprovocation testing was performed in 7 subjects (3 normal, 4 with mild asthma) after pretreatment with phosphate-buffered saline (PBS), atropine, chlorpheniramine, or indomethacin. We determined the nebulizer concentration of PAF which reduced specific airway conductance (SGaw) 35% (PC35 SGaw) and the slope of the PAF dose-response curve. Atropine produced baseline bronchodilatation (SGaw increased 50%), while chlorpheniramine and indomethacin had no effect on baseline pulmonary function. Atropine increased airway responsiveness to PAF: the PC35 SGaw decreased 40% (p less than 0.05) and the slope of the PAF dose-response curve increased 86% (p less than 0.05). In contrast, chlorpheniramine inhibited the airway response to PAF: the PC35 SGaw increased 87% (p less than 0.05), while the slope of the PAF dose-response curve decreased an insignificant 37%. Indomethacin did not affect either measurement. Chlorpheniramine also prevented the PAF-induced facial flushing and feeling of warmth; atropine and indomethacin did not. These results suggest that PAF-induced bronchoconstriction in humans is mediated at least in part by histamine release, not by cholinergic or cyclooxygenase-dependent mechanisms. Other indirect effects, such as the release of sulfidopeptide leukotrienes, or a direct effect on airway smooth muscle may also contribute to PAF-induced bronchoconstriction. Why atropine heightened the airway response to PAF is unclear.
 ...
PMID:Mechanism of platelet activating factor-induced bronchoconstriction in humans. 319

Plasma levels of histamine and Nt-methylhistamine were measured simultaneously by high performance liquid chromatography during the intravenous infusion of histamine acid phosphate in six normal volunteers. Progressive, dose-related increases in plasma histamine were noted, reaching a maximum value of 3.1 +/- 0.14 ng ml-1 corresponding to a maximum infusion rate of 180 ng kg-1 min-1 (means +/- SEM). Increases in plasma histamine were accompanied by a significant dose-related fall in mean diastolic blood pressure (baseline 74.0 +/- 4.4 mm Hg falling to 60.0 +/- 3.3 mm Hg at maximum infusion rate, p less than 0.001) and an increase in pulse rate (baseline 76.3 +/- 2.8 beats min-1 rising to 89.24 beats min-1 at maximum infusion rate, p less than 0.05). All subjects exhibited facial flushing, the threshold plasma histamine level for this effect being 1.3 +/- 0.15 ng ml-1 corresponding to an infusion rate of 60 ng kg-1 min-1. Elevation of plasma Nt-methylhistamine was seen in only one subject, who exhibited a level of 0.5 ng ml-1 at the highest infusion rate. These results suggest that measurements of plasma Nt-methylhistamine are unlikely to provide a useful index of histamine release into the circulation.
 ...
PMID:Histamine and Nt-methylhistamine in the circulation during intravenous infusion of histamine in normal volunteers. 321 6

A method for inhibiting the adhesion of stone fragments in comminution is presented. Surfaces are coated with a molecular layer of so-called "excluding" polymer. In experimental tests, rat bladders were injected with comminuted urinary stone (phosphate or oxalate) in saline which contained small amounts of excluding polymer (0.1% hyaluronic acid or polyvinyl pyrrholidone). The urinary tract was then irrigated with fresh polymer solution and examined for residual stone. A ten-fold reduction in particle count was obtained, compared with irrigation with normal saline. The possible applications in percutaneous and extracorporeal lithotripsy are discussed. It seems that the "coagulum" and "exclusion" types of polymer irrigant might find complementary uses: the former for manual extraction of coarse particles and the latter for flushing out after fine comminution.
 ...
PMID:Polymer treatments reduce adhesion of comminuted stone in rat bladder. 369 Jan 80

An in situ flushing solution was evaluated with regard to the following: (1) its ability to protect the kidney during 60, 90, and 120 minutes of normothermic ischemia; (2) the effects of using an intracellular versus extracellular electrolyte composition in the flushing solution; and (3) the ability of the flushing solution to complement in situ hypothermia as a protective measure during long-term ischemia. Rat kidneys were briefly flushed in situ with an isotonic phosphate buffered solution (pH 7.2) containing 50 milliosmole of sucrose. The left renal pedicle was then immediately clamped to render the kidney ischemic and to hold the flushing solution in the kidney. Following removal of the pedicle clamp, a contralateral nephrectomy of the right kidney was performed and daily serum creatinine levels determined to evaluate postischemic renal function. The results indicate the following: (1) the flushing procedure is very effective in preventing postischemic acute renal failure following 60 minutes of normothermic ischemia, but is considerably less effective for ischemic times of 90 minutes or more; (2) an intracellular electrolyte composition in the flushing solution does not improve the protective effects of this solution; and (3) the flushing procedure can significantly improve on the protection otherwise provided by in situ hypothermia.
 ...
PMID:Evaluation of a flushing solution designed to protect kidneys from in situ ischemia. 402 28

Previous workers from this laboratory observed considerable variation in the proportions of acetic and lactic acids produced in pure broth culture as compared to consistently high proportions of acetic acid produced in the sourdough and flour suspension systems. In the latter the proportion of acetic acid was always in the range of 20 to 35% of the total, whereas in pure broth culture frequently less than 5% acetic acid was produced. In the natural environment, the sourdough bacteria, tentatively identified as lactobacilli, coexist with a yeast, Saccharomyces exiguus, and this study was undertaken to determine whether this yeast or flour ingredients including glucose or other factors were involved in this variable production of acetic acid. The proportion of acetic acid produced in broth culture on maltose, the preferred carbohydrate source, was found to depend almost entirely on the degree of aeration. Essentially anaerobic conditions, as obtained by thorough evacuation and flushing with CO(2) or N(2), resulted in very low (5% or less) proportions of acetic acid. Aerobic conditions, achieved by continuous shaking in cotton-plugged flasks, yielded high levels (23 to 39% of the total) of acetic acid. Similar effects of aeration were observed with glucose as the substrate, although growth was considerably slower, or in nonsterile flour suspension systems. It is theorized that, under aerobic conditions, the reduced pyridine nucleotides generated in the dissimilation of carbohydrate are oxidized directly by molecular oxygen, thereby becoming unavailable for the reduction of the acetyl phosphate intermediate to ethyl alcohol, the usual product of anaerobic dissimilation of glucose by heterofermentative lactic acid bacteria. Comparative studies with known strains of homo- and heterofermentative lactobacilli showed similar effects of aeration only on the heterofermentative strains, lending additional support to the tentative grouping by previous workers from this laboratory of the sourdough bacteria with the heterofermentative lactobacilli.
 ...
PMID:Factors affecting organic acid production by sourdough (San Francisco) bacteria. 504 65


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>