Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0848332 (Spots)
 453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cell extract protein content of acetate- and methanol-grown Methanosarcina thermophila TM-1 was examined by two-dimensional polyacrylamide gel electrophoresis. More than 100 mutually exclusive spots were present in acetate- and methanol-grown cells. Spots corresponding to acetate kinase, phosphotransacetylase, and the five subunits of the carbon monoxide dehydrogenase complex were identified in acetate-grown cells. Activities of formylmethanofuran dehydrogenase, formylmethanofuran:tetrahydromethanopterin formyltransferase, 5,10-methenyltetrahydromethanopterin cyclohydrolase, methylene tetrahydromethanopterin:coenzyme F420 oxidoreductase, formate dehydrogenase, and carbonic anhydrase were examined in acetate- and methanol-grown Methanosarcina thermophila. Levels of formyltransferase in either acetate- or methanol-grown Methanosarcina thermophila were approximately half the levels detected in H2-CO2-grown Methanobacterium thermoautotrophicum. All other enzyme activities were significantly lower in acetate- and methanol-grown Methanosarcina thermophila.
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PMID:Protein content and enzyme activities in methanol- and acetate-grown Methanosarcina thermophila. 230 49

1. A substance (Art. HS) which resembles the 18-monoacetate of D-aldosterone (18 MA) in its biological actions is found in arterial blood of cats and sheep: Art. HS is assayed in terms of antidiuretic activity equivalent to synthetic 18 MA.2. In cats under chloralose anaesthesia, dialysis of arterial blood (2-3 ml./min) in a small external circuit (8-15 ml.) without disturbance of heart rate, blood pressure or respiration, predicts a physiological concentration of Art. HS equivalent to 31.5-51.9 ng 18 MA/100 ml. Efficiency of dialysis assumed in this calculation is 100%.3. Art. HS is almost evenly distributed throughout the plasma and formed elements of blood.4. Concentrations of Art. HS found during severe arterial haemorrhage are equivalent to 188 +/- 6.7 and 151 +/- 9.2 ng 18 MA/100 ml. in cats and sheep respectively.5. Art. HS has been isolated from 27.6 l. sheep arterial blood by ethyl acetate: chloroform 1:1 extraction, defatting by partitioning between methanol and petroleum ether and purifying by seven-stage thin layer chromatography on MN Kieselgel UV(254). Final yield was equivalent in activity to 21.6 mug 18 MA. Synthetic 18 MA was used as R(F) marker. Spots of 2 mug 18 MA are visible on MN Kieselgel UV under U.V. Art. HS activity equivalent to 21.6 mug 18 MA cannot be seen.6. Art. HS was not detectable in IVC blood of cats under chloralose anaesthesia during haemorrhage. The threshold for detection was the equivalent of 15-20 ng 18 MA/100 ml.7. Art. HS resembles a substance liberated by the heart (Lockett & Retallack, 1970a, b, 1971) in chromatographic properties, biological properties and stability in aqueous solution. Art. HS is very much more stable in aqueous solution than 18 MA.
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PMID:The isolation of a renally active substance from arterial blood. 504 65

The enantiomeric resolution of certain amino acids and some of their dansyl derivatives was achieved on thin silica gel plates impregnated with (1R,3R,5R)- 2-Azabicyclo[3,3,0]octan-3-carboxylic acid, which is an industrial waste material, and a proline analogue non proteinogenic alpha-amino acid. Different combination of 0.5 M NaCl-MeCN were found to be successful in resolving dansyl-DL-amino acids; addition of methanol was required in some cases. Spots were visualised using a fixed wavelength (254 nm) ultraviolet chamber. Resolution of DL-amino acids was successful in different combinations of MeCN-MeOH-H2O and detection was made with ninhydrin (0.2% in acetone).
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PMID:TLC resolution of enantiomers of amino acids and dansyl derivatives using (1R,3R,5R)-2-azabicyclo[3,3,0]octan-3-carboxylic acid as impregnating reagent. 937 10

The resolution of (+/-)-atenolol, (+/-)-propranolol and (+/-)-metoprolol into their enantiomers was achieved by TLC on silica-gel plates impregnated with optically pure L-lysine (0.5%) and L-arginine (0.5%) as the chiral selectors. In all cases, different combinations of acetonitrile-methanol solvent systems were found to be successful in resolving these compounds. Spots were detected using iodine vapour. The detection limit for both (+/-)-atenolol and (+/-)-propranolol was 2.6 microg and for (+/-)-metoprolol, it was 0.26 microg.
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PMID:Direct enantioseparation of some beta-adrenergic blocking agents using impregnated thin-layer chromatography. 965 83

A substantially available identification system for Sildenafil in health foods was established using 3 different analytical methods; i.e. TLC, preparative TLC/MS and HPLC/photo-diode array. Sildenafil in health foods was extracted with ethyl acetate under alkaline conditions as sample solutions for TLC and preparative TLC, and also extracted with 50% methanol and then diluted with solution of HPLC mobile phase for HPLC. The sample solution for TLC was applied to Silica gel 60 F254 plates with chloroform/methanol/28% ammonia (90:1:5, under layer) as mobile phase. Spots were located under UV radiation at 254 nm and 366 nm, and spraying dragendorff reagent. The conditions for preparative TLC were the same as these of TLC method, and samples abtained from preparative TLC were determined by MS with APCI interface, under both positive and negative modes. The HPLC analysis was carried out on a column of Cosmosil 5C18-AR (4.6 mm x 150 mm, 5 microns) with 0.05 mol/l phosphate buffer pH 3.0/acetonitrile(73:27) as mobile phase and the eluate was monitored by a photo-diode array detector. The quantitative analysis was available, when the peak of this sample on HPLC was detected at 290 nm. When this system was applied to commercial health foods, Sildenafil was identified and their contents were 25 mg-45 mg/tablet or bottle. These contents nearly correspond to that in Viagra, 25 mg, 50 mg/tablet. Therefore, there is a fear of side effects for Sildenafil, when it is taken as health foods.
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PMID:[Identification system for Sildenafil in health foods]. 1167 79

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.
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PMID:Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition. 1247 35

In this study a clear separation between seven analogues of artemisinin on thin-layer chromatography (TLC) is presented. The developed TLC method is carried out on a RP-C18 thin-layer plate using acetonitrile-water (50:25 v/v) as the mobile phase. Spots are visualized by derivatization with an acidified 4-methoxybenzaldehyde reagent in methanol-water. This method allows the separation of a diverse group of compounds that have versatile hydrophilic/lipophilic characteristics; namely artemisinin, artesunate (AS), artelinic acid (AL), arteether (AE), both isomers of artemether (AM) (alpha and beta), dihydroartemisinin, and desoxyartemisinin. Separation of some degradation products and impurities, down to 2%, allows quality control and stability investigation of all actives in raw material and pharmaceutical formulations. The method is further developed via densitometric measurement for quantitative determination purposes for AL and AS. The derivatization technique is evaluated, showing good stability and reproducibility of the coloring process. Percent relative standard deviation values are less than 5% for replicates, and linearity is obtained in the range of 0.5 to 8 microg. A comparative study with high-performance liquid chromatography (HPLC) on a C18 column, applying the same mobile phase, proves the suitability of the TLC method, in which almost all presented analytes are separated from each other. In contrast, HPLC requires at least a 20-min analysis to chromatograph all of the compounds and only betaAM and AE are clearly separated from each other and from the other compounds.
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PMID:Development of a reversed-phase thin-layer chromatographic method for artemisinin and its derivatives. 1535 72

The enantiomeric resolution of (+/-)-ibuprofen into its enantiomers was achieved by TLC on silica gel plate using optically pure (-)-brucine as a chiral selector and acetonitrile-methanol (5:1, v/v) as the solvent system. Spots were located in an iodine chamber. The detection limit was 4.9 microg. The effect of concentration of the chiral selector, temperature and pH on resolution has been studied.
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PMID:Resolution of (+/-)-ibuprofen using (-)-brucine as a chiral selector by thin layer chromatography. 1538 71

Plasma phospholipids in several common mammalian species, including cat, cow, dog, goat, guinea pig, horse, pig, rabbit, rat, and sheep, were analyzed by using chromatographic and spectrophotometric methods. Lipids were extracted from plasma with chloroform-methanol 2ratio1 (v/v) and freed of nonlipid material by passage through a Sephadex column. The phospholipids were separated by two-dimensional thin-layer chromatography (TLC). Spots were identified by spray reagents, also by infrared spectrophotometry. The relative distribution of the phospholipids was determined by phosphorus analysis on the spot scraped off the TLC plate.Lecithin, lysolecithin, and sphingomyelin were found in the plasma of all species and accounted for more than 95% of the phospholipids except in the rodents. Lecithin was without exception the major phospholipid in plasma (56 to 83%). Lysolecithin and sphingomyelin content varied between 8 and 23% and 6 and 15% respectively. Phosphatidyl ethanolamine and phosphatidyl inositol were the only noncholine-containing phospholipids detected (detection limits 0.2%) in the plasma of these species. Together these compounds usually made up less than 5% of the total phospholipid. Rodents were an exception, especially the guinea pig, which had 21.7% phosphatidyl ethanolamine.
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PMID:The phospholipid composition of plasma in various mammalian species. 1780 59

A selective and sensitive liquid chromatography (LC)-atmospheric pressure chemical ionisation (APCI)-mass spectroscopic (MS) assay of canrenone has been developed and validated employing Dried Blood Spots (DBS) as the sample collection medium. DBS samples were prepared by applying 30 microl of spiked whole blood onto Guthrie cards. A 6mm disc was punched from the each DBS and extracted with 2 ml of methanolic solution of 17alpha-methyltestosterone (Internal Standard). The methanolic extract was evaporated to dryness and reconstituted in acetonitrile:water (1:9, v/v). The reconstituted solution was further subjected to solid phase extraction using HLB cartridges. Chromatographic separation was achieved using Waters Sunfire C18 reversed-phase column using isocratic elution, followed by a high organic wash to clear late eluting/highly retained components. The mobile phase consisted of methanol:water (60:40, v/v) pumped at a flow rate of 0.3 ml/min. LC-APCI-MS detection was performed in the selected-ion monitoring (SIM) mode using target ions at m/z 341.1 and 303.3 for canrenone and internal standard respectively. The selectivity of the method was established by analysing DBS samples from 6 different sources (individuals). The calibration curve for canrenone was found to be linear over 25-1000 ng/ml (r>0.994). Accuracy (% RE) and precision (% CV) values for within and between day were <20% at the lower limit of quantification (LLQC) and <15% at all other concentrations tested. The LLOQ of the method was validated at 25 ng/ml. Clinical validation of the method was achieved by employing the validated method for analysis of 160 DBS samples from 37 neonatal and paediatric patients.
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PMID:Development and validation of a dried blood spot-LC-APCI-MS assay for estimation of canrenone in paediatric samples. 2015 5


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