Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.1.7 (acetylcholinesterase)
28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A series of trifluoromethyl ketones that reversibly inhibit acetylcholinesterase and pseudocholinesterase were synthesized. By analogy to chymotrypsin and on the basis of data reported here, we propose that the active-site serine adds to the ketone to form an ionized hemiketal. The compound (5,5,5-trifluoro-4-oxopentyl)trimethylammonium bicarbonate (1) inhibits acetylcholinesterase with Ki = 0.06 X 10(-9)M and pseudocholinesterase with Ki = 70 X 10(-9)M. Replacement of the nitrogen of 1 by carbon (compound 2) increases Ki for 1 200-fold for acetylcholinesterase but does not significantly alter Ki for pseudocholinesterase. The Ki for the methyl ketone corresponding to 2 is 2 X 10(-4)M for both enzymes, as compared with 12 X 10(-9)M for the trifluoromethyl ketone (acetylcholinesterase). For both enzymes, a linear decrease in log Ki with decreasing pK of the inhibitor hydrate was observed with ketones containing from 0 to 3 fluorines. We attribute this effect to the stabilization of the hemiketal oxyanion. The reduction of the pK of the hemiketal by the trifluoromethyl group is an important contributing factor to the low Ki of trifluoromethyl ketones. The inhibition of acetylcholinesterase by tetramethylammonium chloride and trifluoroacetone was compared to the inhibition by 1, which is a composite of the two smaller inhibitors. The entropic advantage of combining the smaller inhibitors into one molecule is 1.1 X 10(3)M. Inhibitors with Ki less than or equal to 70 X 10(-9) M are slow binding (Morrison, 1982; Morrison & Walsh, 1988). The kinetic data do not require formation of a noncovalent complex prior to formation of the ketal, although such a complex(es) cannot be excluded.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Inhibition kinetics of acetylcholinesterase with fluoromethyl ketones. 260 96

A subacute toxicity study of propiverine hydrochloride (P-4), a new anti-pollakiuria agent, was carried out using male and female Wistar rats. P-4 was orally administered to rats at dose levels of 2, 10, 50 and 150 mg/kg/day for 13 weeks, followed by 5 weeks recovery period. The results obtained are as follows: 1. In the general conditions, transient salivation was observed immediately after administration and blotted fur at lower abdomen was noted in rats given 50 mg/kg/day or more. There were no deaths related to P-4. 2. Body weight gain was depressed in males given 50 mg/kg/day or more and females given 150 mg/kg/day. No significant changes in food consumption were observed. Water consumption increased in the groups of 50 mg/kg/day or more. 3. Urinalysis revealed an increase of urine volume, decreases of osmotic pressure, protein and urobilinogen, and a slight increase in excretion of electrolyte in rats given 50 mg/kg/day or more. 4. Hematological examinations revealed slight changes such as an increase in erythrocyte count and a shortening of APTT in rats given 150 mg/kg/day. 5. Serum biochemical examinations showed a decrease in triglyceride and increases in gamma-GTP and AlP activities, and urea nitrogen in males given 50 mg/kg/day or more and females given 150 mg/kg/day. Additionally, decreases in total and free cholesterol, and phospholipid for males and an increase of total cholesterol and a decrease of cholinesterase activity for females were detected. 6. At autopsy, atrophy of thymus and spleen was observed in rats given 50 mg/kg/day or more, but without histopathological correlation. Histopathological examinations revealed hypertrophy and fatty degeneration of hepatocytes, which were accompanied with increases of absolute and/or relative liver weight, in males given 50 mg/kg/day or more and females given 150 mg/kg/day. Electron-microscopy showed proliferation of smooth endoplasmic reticulum in the same groups. In the kidney, eosinophilic and intranuclear inclusions in the tubular epithelium were detected, in which cytoplasm there were no toxic injuries, in males given 10 mg/kg/day or more and females given 50 mg/kg/day or more. 7. After 5 weeks recovery period, above-mentioned changes were generally disappeared, suggesting that these were reversible. 8. The non-effective dose levels and the toxic dose levels of P-4 were estimated to be 2 mg/kg/day for males and 10 mg/kg/day for females, and 50 mg/kg/day for males and 150 mg/kg/day for females, respectively.
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PMID:[Thirteen-week oral toxicity study of propiverine hydrochloride in rats]. 260 52

The influence of meat containing ammonia in concentrations of 0.1 and 0.3% was studied in chronic experiments on 3 generations of rats (males and females). To investigate the function of the liver, kidneys and CNS, alanine-aminotransferase, lactate dehydrogenase activity, and the content of the total protein and its fractions were assayed in the blood serum; cholinesterase activity, sulfhydryl groups, urea and residual nitrogen were assayed in the blood, as well as the parameters of rheobase, chronaxie and summation of subliminal impulses. The results of the investigation have shown that meat containing ammonia in concentrations of 0.1 and 0.3% produces a detrimental effect on the experimental animals, the highest effect being recorded with an ammonia concentration of 0.3%.
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PMID:[Study of the possible harmful action of meat containing ammonia on experimental animals]. 260 59

The health status of broilers fed diets with varying protein contents in the presence of ochratoxin A (OA) were evaluated using clinical-chemistry techniques for blood analysis. A completely randomized, 3 x 4 factorial design was utilized: 14, 18, 22, and 26% of dietary protein and 0, 2, and 4 mg/kg of OA. The broilers were raised to 3 wk of age, at which time blood was collected and various hematological parameters were evaluated. The serum was analyzed for various enzyme activities and for concentrations of metabolites and minerals using an automated, clinical-chemistry analyzer and an atomic-absorption spectrophotometer. Adding OA to the diets of broilers decreased the hemoglobin concentration, corpuscular volume, and the activity of serum alkaline and phosphatase but increased the activity of gamma-glutamyl transferase. Adding protein to the diet increased the activity of the serum aspartate aminotransferase, creatine kinase, and alkaline phosphatase. Adding OA to the diet of broilers decreased the concentrations of serum total protein, as well as the concentrations of albumen and cholesterol and increased the concentrations of serum creatinine and uric acid. The concentrations of serum total protein, albumin, urea nitrogen, and triglyceride were increased by adding protein to the diet. The concentrations of calcium, potassium, and inorganic phosphorus in the serum decreased when OA was added to the diet; but the concentrations of calcium and potassium content in the serum increased along with dietary protein. A regression analysis suggested that dietary protein was synergistic toward OA with regard to the blood levels of cholinesterase, lactate dehydrogenase, and glucose.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ochratoxin A and dietary protein. 2. Effects on hematology and various clinical chemistry measurements. 262 21

Groups of 21 male and 21 female Sprague-Dawley (SD) rats were fed diets containing pyriproxyfen at concentrations of 0, 80, 400, 2,000 and 10,000 ppm for 6 months. No death was found in any group. Alopecia in the neck and/or back, and soft feces were noticed in both sexes fed 10,000 ppm. A marked decrease in body weight gain was observed in both sexes fed 10,000 ppm throughout the treatment period, accompanying a decrease in food-consumption and an increase in water-intake during the initial stage of treatment. In terms of urinalysis, proteinuria, increases in K excretion, and, in number, yellowness or browish-yellowness in appearance, were observed in both sexes fed 10,000 ppm. In females fed 10,000 ppm, increases in bilirubin, Na excretion and specific gravity, and a decrease in ketone bodies, were observed. In hematology, decreases in erythrocyte count, hemoglobin concentration and hematocrit value, were observed in both sexes fed 10,000 ppm and in males fed 2,000 ppm. Also, an increase in MCH (in males), decreases in MCHC and platelet count (in females) were observed in 10,000 ppm group. Blood biochemistry revealed increases in total protein, albumin, alpha 2-globulin fraction, blood urea nitrogen, calcium (in both sexes fed 10,000 ppm), A/G ratio (in males fed 2,000 and 10,000 ppm), total cholesterol, phospholipid (in males fed 2,000 and 10,000 ppm, and in females fed 10,000 ppm), sodium (in females fed 2,000 and 10,000 ppm), gamma-glutamyl transpeptidase activity (in males fed 10,000 ppm) and alpha 1-globulin fraction (in females fed 10,000 ppm), and decreases in glucose, GOT (in both sexes fed 10,000 ppm), beta-globulin fraction (in males fed 2,000 and 10,000 ppm, and in females fed 10,000 ppm), GPT (in females fed 2,000 and 10,000 ppm), triglyceride, potassium (in males fed 10,000 ppm), and cholinesterase activity (in female fed 10,000 ppm). In organ weight, increases in liver (in males fed 2,000 ppm and 10,000 ppm, and in females fed 10,000 ppm), kidney (in both sexes fed 10,000 ppm) and thyroid (in females fed 10,000 ppm) and a decrease in pituitary (in females fed 2,000 and 10,000 ppm) were observed. Gross pathology revealed a higher incidence of blackish-brown coloration of the liver, and a lower incidence of accentuated lobular pattern of the liver (in males fed 10,000 ppm). An enlargement of the liver was seen in a few of both sexes fed 10,000 ppm. Histopathological examination showed that the sole effect attributable to treatment of this compound was on slight hypertrophy in the liver of both sexes fed 10,000 ppm, with a higher incidence.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[A six-month chronic dietary toxicity study of pyriproxyfen in rats]. 273 65

Two metabolites, isolated from the urine of rats given the cholinesterase reactivator HI-6 intravenously, still contained quaternary nitrogen atoms and therefore could not be extracted from aqueous solutions by organic solvents. Both metabolites were isolated by preparative high performance liquid chromatography and were identified using mass spectrometry, gas chromatography, infrared spectrometry, ultraviolet spectrometry and proton nuclear magnetic resonance spectrometry. The structures were confirmed by in-vitro preparation of the compounds. both metabolites contained 2-pyridone moieties. One had an intact pyridinium-aldoxime moiety, and therefore could still be therapeutically active. The excretion of unchanged HI-6 together with the two identified metabolites does not provide for a 100% mass balance, indicating that in the rat, other, as yet unidentified, metabolites must be formed.
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PMID:Identification of two metabolites of the cholinesterase reactivator HI-6 isolated from rat urine. 288 Sep 78

The progression of effects induced by administration of ochratoxin A were characterized in young male broiler chickens (Hubbard x Hubbard). The experimental design consisted of four dietary treatments of ochratoxin A (0, 1.0, 2.0, and 4.0 micrograms ochratoxin A/g feed) and 11 replicates of 10 broilers/replicate. Broilers were housed in electrically heated batteries with feed and water available ad libitum. Broilers were weighed, bled, killed by cervical dislocation, and necropsied at 3, 6, 9, 12, 15, 18, and 21 days of age. Toxicity of ochratoxin A to broilers was evident as early as 6 days of age, when significant (P less than .05) growth depression occurred at 4.0 micrograms dietary ochratoxin A/g feed. Dietary ochratoxin A significantly increased the relative weights of the liver, kidney, spleen, pancreas, and gizzard. Anemia, characterized by a significant decrease in packed-cell volume and hemoglobin levels, was present during ochratoxicosis. Hepatotoxicity of dietary ochratoxin A was evident through an observed significant reduction in serum levels of total protein, albumin, globulin, cholesterol, triglyceride, and blood urea nitrogen, and a significant increase in the serum activities of gamma glutamyl transferase and cholinesterase. A significant increase in serum uric acid and creatinine levels was indicative of nephrotoxicity. These data provide a description of the progression of ochratoxicosis in broilers that should be useful in diagnosis and in improved understanding of ochratoxicosis.
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PMID:Progression of ochratoxicosis in broiler chickens. 290 99

Soluble interleukin 2 receptors (sIL 2R) in the sera of patients with viral liver diseases were quantified with a solid-phase enzyme immunoassay using two monoclonal antibodies against the receptors. The sIL 2R levels in patients with acute hepatitis, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma were significantly higher than those in control subjects. In acute hepatitis patients, the high levels of sIL 2R observed during the florid stage returned to normal during remission. Levels in patients with chronic active hepatitis were significantly higher than in those with chronic persistent and lobular hepatitis, and levels observed during the exacerbation phase of chronic hepatitis were higher than they were during remission. Thus, in chronic hepatitis, sIL 2R levels increased in proportion to the inflammatory activity, and correlated well with serum transaminase (glutamic oxaloacetic transaminase: SGOT, glutamic pyruvic transaminase: SGPT) activities, but not with blood urea nitrogen or creatinine concentrations. In patients with a high degree of focal and piecemeal necrosis, serum sIL 2R levels increased further during recombinant interleukin 2 therapy. In post-hepatitic liver cirrhosis and hepatocellular carcinoma, sIL 2R levels correlated with serum cholinesterase and creatinine concentrations, but not with transaminase activities. Measurement of serum sIL 2R levels in patients with liver disease but without renal injury, may help in the diagnosis of inflammation in hepatitis, a process in which interleukin 2 may participate.
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PMID:Increased serum soluble interleukin 2 receptor levels in patients with viral liver diseases. 306 11

A prospective randomized double blind investigation was made in 24 multiple injured patients. All patients were treated with a combined parenteral-enteral nutrition during 7 days. A group of 11 patients received as a continuous infusion over 16 h 60 mg/kg BW carnitine daily. Beside carnitine and acetylcarnitine levels in plasma and urine the following parameters were determinated to evaluate the effect of carnitine: for the metabolism of fatty acids: triglycerides, free fatty acids (FFA), alpha-hydroxy-butyrate for the metabolism of carbohydrates: glucose, insulin and lactate in plasma. Finally for amino acid metabolism: urea, creatinine, cholinesterase and kolloid osmotic pressure in plasma as well as ureanitrogen and alpha-aminonitrogen excretion in urine. In the patients receiving carnitine especially acetyl-carnitine in plasma and acetyl-carnitine excretion in urine increased, proving that the administered carnitine can pass through the mitochondrial membrane. In these patients the plasma level of FFA was markedly lower than in the group without carnitine. Simultaneously the level of the alpha-hydroxybutyrate was elevated, equivalent to an increased oxydation of fatty acids. There was no difference between the two groups in the metabolism of carbohydrates. Administration of carnitine caused a slight increase of the production of urea (PU), catabolism could not be reduced. The excretion of alpha-aminonitrogen in urine augmented after carnitine infusion. Carnitine is an AA itself and so the amount of excreted alpha-amino nitrogen will increase; additionally the reabsorption of AA in the proximal renal tubulus may be inhibited by carnitine.
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PMID:[Experiences with L-carnitine in the post-stress phase]. 310 Apr 46

The effects of total parenteral nutrition (TPN) on some nutritional variables were prospectively investigated in 12 severely cachectic patients with advanced cancer. The following variables were determined before and at 5-day intervals during the 20-day administration of TPN: anthropometric indices (body weight, arm circumference, triceps skinfold, arm muscle circumference, arm muscle area, arm fat area, total body muscle mass); biochemical indices (total protein, albumin, cholinesterase, total iron binding capacity, thyroxin-binding prealbumin, retinol binding protein, urinary 3-methylhistidine and creatinine excretion, nitrogen balance); and peripheral lymphocyte count. TPN was delivered at 49.5 nonprotein kcal/kg-1/day-1 (80% as dextrose and 20% as fat) and amino acids 1.9 g/kg-1/day-1. A significant increase was obtained in body weight, triceps skinfold, arm fat area, and retinol binding protein. All remaining anthropometric and biochemical parameters did not show any significant positive or negative change, although nitrogen balance remained positive. No significant liver toxicity was apparent after the TPN period. It was concluded that although TPN is unable to completely reverse some nutrition-related variables in cachectic patients with cancer, most patients were kept within a normal range and some improved. Therefore, further deterioration of the nutritional state, which is characteristic of this phase of disease, was at least prevented.
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PMID:Total parenteral nutrition prevents further nutritional deterioration in patients with cancer cachexia. 310 24


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