Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085631 (agitation)
 12,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The stability of taxol (NSC-125973) in various diluents and containers was determined, and the extent of leaching of di(2-ethylhexyl) phthalate (DEHP) from polyvinyl chloride (PVC) bags caused by the taxol formulation was measured. A taxol formulation consisting of a 6-mg/mL solution of taxol in 50% polyoxyethylated castor oil and 50% dehydrated ethanol was added to 50- and 100-mL glass bottles, PVC infusion bags, and polyolefin containers containing 5% dextrose injection or 0.9% sodium chloride injection to give initial nominal taxol concentrations of 0.3, 0.6, 0.9, and 1.2 mg/mL. The containers were maintained at 20-23 degrees C for 12-24 hours. Samples were assayed by stability-indicating high-performance liquid chromatography, and clarity was determined visually. An experiment was run to ascertain whether DEHP would leach from a PVC administration set during a simulated infusion. There was no substantial loss of taxol over 24 hours. Filtration through a membrane resulted in no loss of taxol. All the solutions initially appeared hazy. Solutions stored in PVC bags became more hazy with time than solutions stored in glass or polyolefin containers. The haze seen in PVC bags was traced to leaching of DEHP. Agitation had no effect on the extent of leaching. Leaching was also seen during simulated delivery through PVC administration sets. No DEHP was detected when solutions were stored in glass or polyolefin containers and infused through polyethylene-lined sets. At the dilutions studied, taxol was visually and chemically stable for up to 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Stability, compatibility, and plasticizer extraction of taxol (NSC-125973) injection diluted in infusion solutions and stored in various containers. 167 94

The dissolution rate of micronized griseofulvin has been investigated, both for the agglomerated raw material and the material formulated as an ordered mixture, by means of the USP XX paddle method. During the experiments, which were performed at sink condition and constant temperature, the effects of adding a surfactant and of agitation were tested. The ordered mixture with sodium chloride gave a fast dissolution rate, practically independent of the test parameters. Micronized griseofulvin alone gave dissolution profiles that were improved by adding polysorbate 80 and by increased agitation, but the dissolution rates obtained were much lower than those for the ordered mixture. It was concluded that the rate limiting step in the dissolution of griseofulvin as the raw material is the penetration of the dissolution medium into the agglomerates. With an ordered mixture, these agglomerates were deaggregated during the mixing process, producing a system in which the entire external surface area of the primary particles was exposed to the dissolution medium. This conclusion was supported by calculation of the contact surface areas taking part in the dissolution process for the systems tested. The procedure developed in this study could be applied to preformulation work where a cohesive, low solubility drug of hydrophobic nature is to be formulated.
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PMID:The use of ordered mixtures for improving the dissolution rate of low solubility compounds. 287 Nov 48

1. Two polysaccharides were isolated from the interstitial matrix surrounding the photoreceptor cells of cattle retina. They were liberated from this region of the tissue in a soluble form after agitation of whole retinas in 0.9% sodium chloride. One, which comprises two-thirds of the polysaccharides present, is a hyaluronidase-sensitive ;half-sulphated' chondroitin sulphate containing uronic acid, galactosamine and sulphate in the molar proportions 1.27:1.0:0.54. The other is a hyaluronidase-resistant non-sulphated heteropolysaccharide for which the name sialoglycan is proposed. It contains galactose, glucosamine and sialic acid in the molar proportions 2.4:1.0:0.4. Both polysaccharides contain only small amounts of nitrogen in excess of the amount calculated from their amino sugar and sialic acid content. 2. A similar combination of mucopolysaccharides is associated with the pigment epithelial-cell layer but in quantities only one-fifth of those present in the adjacent matrix area. 3. The ease with which they are released into aqueous media is consistent with the assumption that they are present in the extracellular spaces in both of these tissue layers. 4. The retinal residue left after removal of the two soluble polysaccharides is rich in amino sugar- and sialic acid-containing polymers, which appear to be firmly bound to the tissue fragments. 5. About one-third of the sialic acid and one-tenth of the amino sugar could be extracted with chloroform-methanol. The components in this fraction were tentatively identified as gangliosides. 6. Digestion of the chloroform-methanol-insoluble residue with Pronase yielded as the principal product a heteropolysaccharide containing 16.5% of glucosamine, 24.3% of neutral sugar (galactose plus fucose) and 18.1% of sialic acid. This substance has been classified as a sialoglycan of composition similar to (but not identical with) that of the soluble one isolated from the matrix area of the tissue.
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PMID:The acid mucopolysaccharides of cattle retina. 423 42

A study was carried out to determine the effect of different solvents on the extraction of protein fractions in beans. Black bean protein was extracted with the following solvents: distilled water, 0.01 M sodium hydroxide, 0.05 M sodium chloride, and 70% ethanol. By using each solvent under different conditions, it was possible to establish the optimum ones for the best extraction and fractionation of proteins from leguminous seeds. These conditions were the following: one hour agitation at room temperature, three successive extractions with the same solvent, and a ratio of solid to solvent of 1:20 W/V. The effect of 24 different sequences of solvents upon the extraction of protein was also investigated. From the extraction point of view, the best sequence of solvents for extracting the protein was that where NaOH constituted the first solvent used; this sequence, however, has the disadvantage of extracting all the protein from the seed, making it impossible to separate other protein fractions by another solvent. If the purpose of the extraction is to separate different protein fractions, the best sequence of solvents is distilled water or sodium chloride in the first place, followed by ethanol and sodium hydroxide. The need for using standardized methodology for the fractionation of protein from seeds in order to obtain comparable data between research laboratories is emphasized.
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PMID:[Effect of various solvents on the extraction of protein fractions of beans (Phaseolus vulgaris)]. 667 47

With the aim of increasing flexibility in controlling release from microcapsules, mixtures of wall polymers varying in porosity were investigated by phase separation. Eudragit RL and RS (polymethylmethacrylate linear backbone polymers) mixtures differing in polar substituent content and porosity were used as the wall material and were deposited using a non-solvent addition method. Release rates increased with polar group content of the mixtures, using theophylline, potassium dichromate or sodium chloride as model core materials. Theophylline release rate had the same relationship to polar group content as found earlier for urea permeation of cast mixed-polymer films. Release was generally accelerated in these systems when the external medium contained sodium lauryl sulphate as a wetting agent but not consistently, decreasing unexpectedly for RL-theophylline microcapsules. Localized dissolution of core substance was visible microscopically during release from single microcapsules. The release rate was sensitive to agitation intensity only at low wall to core ratios. Temperature change revealed only a single release mechanism for sodium chloride by Arrhenius equation treatment. Buffer ions penetrated coatings readily, changing theophylline release rates and providing clear evidence of diffusion via a pore-capillary mechanism.
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PMID:Gradation of microcapsule wall porosity by deposition of polymer mixtures (Eudragit RL and Eudragit RS). Phase separation of polymer mixtures and effects of external media and conditions on release. 765 May 92

The aim of the present work was to establish in vivo predictive in vitro tests for the tablet erosion of two different compositions (A and B) of hydrophilic matrix tablets based on hydroxypropyl methylcellulose. The tablet erosion was studied in a modified USP II apparatus at different agitation intensities and ionic strengths according to 2(2) factorial design. The in vivo tablet erosion was studied in 8 healthy human volunteers by gamma scintigraphy after administration of the tablets together with breakfast. In vitro agitation intensity increased the erosion rate for both tablets whereas increased ionic strength caused a slower rate for tablet A and a faster rate for tablet B. The choice of in vitro testing conditions proved to be critical for the attainment of in vivo predictive results. The best in vitro/in vivo correlation for the two formulations was obtained at a paddle stirring rate of 140 rpm and a ionic strength of 0.14 obtained by addition of sodium chloride.
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PMID:In vitro and in vivo erosion of two different hydrophilic gel matrix tablets. 970 24

The objective of this study was to evaluate the influence of nonionic surfactants in the presence of glycine and sodium chloride on the physical stability of immunoglobulin G (IgG) in aqueous solution. Among surfactants suitable for parenteral preparation, Polysorbate 80 (Tween 80) and Polyoxyl 35 Castor Oil (Cremophor EL) were selected. The physical stability of IgG in the absence and in the presence of excipients was investigated in aqueous solution during mechanical agitation (concentration of IgG 15%; pH 7.1; temperature 6 +/- 2 degrees C). Suitable concentrations of Tween 80 and Cremophor EL were experimentally determined by surface tension measurements at 6 +/- 2 degrees C. Glycine and sodium chloride were used in different concentrations. The influence of the excipients on the physical stability of IgG in solution has been examined by surface tension measurements, protein content assay (Kjeldahl and HPLC) and differential scanning calorimetry (DSC). Based on the results of the investigations, it was found that Tween 80 and Cremophor EL, used in experimentally determined critical micelle concentration (cmc), decreased the physical stability of IgG in solution. Tween 80 and Cremophor EL in the presence of glycine (1.5 g/l) could stabilize the IgG in solution during mechanical agitation. The comparison of the effects of Tween 80 and Cremophor EL on the physical stability of IgG, showed that Tween 80 had better stabilization effects on IgG in solution under the experimental conditions selected.
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PMID:Effects of nonionic surfactants on the physical stability of immunoglobulin G in aqueous solution during mechanical agitation. 1285 3

Electrolyzed oxidizing water is a relatively new concept that has been utilized in agriculture, livestock management, medical sterilization, and food sanitation. Electrolyzed oxidizing (EO) water generated by passing sodium chloride solution through an EO water generator was used to treat alfalfa seeds and sprouts inoculated with a five-strain cocktail of nalidixic acid resistant Escherichia coli O157:H7. EO water had a pH of 2.6, an oxidation-reduction potential of 1150 mV and about 50 ppm free chlorine. The percentage reduction in bacterial load was determined for reaction times of 2, 4, 8, 16, 32, and 64 min. Mechanical agitation was done while treating the seeds at different time intervals to increase the effectiveness of the treatment. Since E. coli O157:H7 was released due to soaking during treatment, the initial counts on seeds and sprouts were determined by soaking the contaminated seeds/sprouts in 0.1% peptone water for a period equivalent to treatment time. The samples were then pummeled in 0.1% peptone water and spread plated on tryptic soy agar with 5 microg/ml of nalidixic acid (TSAN). Results showed that there were reductions between 38.2% and 97.1% (0.22-1.56 log(10) CFU/g) in the bacterial load of treated seeds. The reductions for sprouts were between 91.1% and 99.8% (1.05-2.72 log(10) CFU/g). An increase in treatment time increased the percentage reduction of E. coli O157:H7. However, germination of the treated seeds reduced from 92% to 49% as amperage to make EO water and soaking time increased. EO water did not cause any visible damage to the sprouts.
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PMID:Treatment of Escherichia coli O157:H7 inoculated alfalfa seeds and sprouts with electrolyzed oxidizing water. 1291 34

Sacks, L. E. (U.S. Department of Agriculture, Albany, Calif.), Peter B. Percell, Richard S. Thomas, and Glen F. Bailey. Kinetics of dry rupture of bacterial spores in the presence of salt. J. Bacteriol. 87:952-960. 1964.-The kinetics of breaking spores in the dry state by use of an excess of sodium chloride and a steel ball in a shaking device were investigated. Under most conditions, disruption is a first-order process. The disruption-rate constant varies directly with the weight of the ball and inversely with the weight of the capsule contents (spores plus salt). Different spore batches differ somewhat in susceptibility to dry rupture. The dry-rupture process is highly reproducible and it is relatively simple to obtain preparations in which exactly 50%, or 90%, of the spores are broken. The procedure is uniquely suited to the disruption of small (5 to 20 mg) samples, but 150 mg of spores have been handled with conventional equipment. Apparently, the chief function of the salt is to separate the spores from one another with a relatively hard, energy-nonabsorbing matrix, preventing aggregation and consequent cushioning of the ball's impact. However, under certain conditions (small ball, high salt, large crystals) appreciable breakage results from collisions of spores with the salt crystals. The minimal salt-spore ratio for efficient breakage depends on the spore batch, but is usually greater than 3:1. Fine glass beads or inorganic salts other than sodium chloride will also serve as the matrix. Electron micrographs of the spores in various stages of disruption are shown, as are electron micrographs of the spore coats of Bacillus macerans, B. megaterium, B. cereus, B. coagulans, and Clostridium bifermentans. Prolonged agitation disintegrates spore coats. The spore coats of B. macerans exhibit a characteristic ribbed structure, previously detected only by carbon replicas of intact spores. Possible application to other biological materials is considered.
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PMID:KINETICS OF DRY RUPTURE OF BACTERIAL SPORES IN THE PRESENCE OF SALT. 1413 36

A headspace solid-phase microextraction (HS-SPME) and gas chromatography (GC) coupled to mass spectrometry (MS) method was developed to identify and quantify 14 volatile oak compounds in aged red wines. The most important HS-SPME variables were optimised by experimental design technique in order to improved the extraction process. The selected conditions were: 10 mL of sample in 20 mL sealed vials with addition of 30% of sodium chloride (saturated solution), divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fibre, 10 min of pre-incubation time, 70 degrees C of temperature and 60 min of extraction time without agitation. The features of the method were established for the studied compounds in terms of linear range, slope and intercept of the calibration graphs, detection and quantification limits and repeatability. For all compounds detection limits were below their threshold levels and repeatability, in terms of relative standard deviation, was good, with values between 3 and 11%. Finally, the method was applied to the analysis of six aged red wines by both internal standard and standard addition calibration methods. The concentrations obtained with both methods were statistically compared.
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PMID:Determination of volatile oak compounds in wine by headspace solid-phase microextraction and gas chromatography-mass spectrometry. 1628 Jan 28


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