bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of the ‘spontaneity’ of self-emulsifiable oils
Authors: Groves M J , Mustafa R M A 
Published: April 2011

Abstract
Self-emulsifiable oils are solutions of surfactants in non-polar solvents which spontaneously form emulsions when added to water. Measurement of the degree of spontaneity has remained subjective. Accordingly, a method has been devised in which a small volume of the oil solution is injected into a flowing stream of water and carried across an intense beam of parallel light from a helium-neon laser. Light scattered from the beam by the dispersed oil droplets is collected by means of fibre optics onto an array of silicon photodiodes and the amplified output is integrated as a function of time. By varying the flow rate of the water stream it is possible to estimate the time required for an emulsifying system to come to its equilibrium state of dispersion under the conditions of the experiment, the ‘spontaneity’ of emulsion formation. Under the experimental conditions employed, systems comprising solutions of phosphated nonylphenolethoxylate (PNE) and phosphated fatty alcohol ethoxylate (PFE) in n-hexane came to equilibrium between 5 and 12 s, depending on the constitution. These times could be approximately correlated with the values for spontaneity estimated by the CPAC dilution test, although this latter test is somewhat subjective. The spontaneity appears to depend on the nature of the material existing within the phase diagram and the anomalous results obtained may be accounted for by the likely presence of a complex formed at the emulsion interface between the PNE, PFE and water during the dispersion process.
Prostaglandins and the anti-inflammatory activity of a human plasma fraction in carrageenan-induced paw oedema in the rat
Authors: Smith M J H , Ford-Hutchinson A W , Elliott P N C , Bolam J P 
Published: April 2011

Abstract
A fraction prepared from normal human plasma inhibits the swelling of the acute carrageenan-induced paw oedema in the rat. Treatment of the animals with prostaglandin E1, arachidonic acid or with substances which either block the formation of prostaglandins or antagonize their action showed that these mediators are concerned in the development of the paw oedema. The anti-inflammatory effect of the plasma fraction in the carrageenan reaction does not involve a specific interference with the prostaglandin system. The plasma fraction is not an inhibitor of the action of SRS-A on the guinea-pig ileum.
An automated sedimentation balance
Authors: Topham John D 
Published: April 2011

Abstract
A method of size grading powders using an automated sedimentation balance is described. The results are recorded as percentages of the total powder present in 1 or 5 μm (intervals) of particle size, after they have been multiplied by a simple correction factor. Analyses of calcium carbonate powder using this balance and the Gallenkamp balance have been compared.
Comparison of the β-adrenoceptors in the myocardium and coronary vasculature of the kitten heart
Authors: Cornish E J , Miller R C 
Published: April 2011

Abstract
The relative potencies of (–)-noradrenaline, (–)-adrenaline, (±)-isoprenaline and (±)-salbutamol have been assessed for their positive inotropic and chronotropic actions on kitten isolated atria. These relative potencies have been compared with those obtained for the relative coronary dilator potencies in two preparations. These were intact hearts perfused by Langendorff’s method and isolated perfused coronary arteries from the kitten. The relative molar potencies for inotropic effects were noradrenaline 1: adrenaline 1: iso-prenaline 7: salbutamol 0.6. The observed ratios for chronotropic effects were not significantly different from those for inotropic effects. The relative potencies of noradrenaline, adrenaline and isoprenaline as myocardial stimulants were similar to their relative potencies as coronary dilators in the intact heart. Similar relative potencies for noradrenaline and isoprenaline were also found in the isolated coronary artery but adrenaline was only one third as active as noradrenaline on this preparation. In both the intact heart and in the isolated coronary artery salbutamol was about one tenth as active as noradrenaline. It was therefore less active relative to noradrenaline as a coronary dilator than as a myocardial stimulant. In spite of these differences in relative potency ratios for myocardial and coronary dilator effects, similar dissociation constants (KB values) for practolol against isoprenaline were found in driven atria and in isolated coronary arteries. Myocardial and coronary vascular β-adrenoceptors thus can both be placed in the general classification of β1-adrenoceptors.
Construction and implantation of a cannula system for repeated injections into localized regions of the rat brain
Authors: Harvey Elizabeth A , Stephens R J 
Published: April 2011

Abstract
The construction and method of implantion of a brain cannula for chronic use in rats is described. All the components of the cannula system are easily made from stainless steel tubing and no machined parts are required. The use of a metal key eliminates the need for tapped holes during implantation. Although little time is required to prepare each animal the system remains firmly fixed to the skull and allows injections to be made accurately into selected brain areas.
Metabolism of quinalbarbitone
Authors: Gilbert J N T , Hetherington W L , Powell J W , Whalley W B 
Published: April 2011

Abstract
The human metabolism of (±)-5-allyl-5-(1′-methylbutyl) barbituric acid (I), quinalbarbitone, taken orally, has been studied. Comparison of g.c. and g.c.-m.s. data from derivatized extracts of urine with similar data from synthetic samples confirmed the presence of the two diastereoisomeric forms of 5-allyl-5-(3′-hydroxy-1′-methylbutyl) barbituric acid (II), 5-allyl-5-(3′-oxo-1′-methylbutyl) barbituric acid (III), 5-allyl-5-(1′-methyl-3′-carboxypropyl) barbituric acid (IV), and 5-(2′,3′-dihydroxypropyl)-5-(1′-methylbutyl) barbituric acid (V) in the urine. There was no evidence for the urinary excretion of unchanged drug. The rate of excretion of these metabolites has been examined in some detail, and rate-limited kinetics shown to apply for excretion of the acid (IV) and the diol (V).
Aggregation of antihistamines in aqueous solution. The effect of electrolyte on the micellar properties of some diphenylmethane derivatives
Authors: Attwood D , Udeala O K 
Published: April 2011

Abstract
The effect of sodium chloride on the micellar properties of the antihistamines, diphenhydramine hydrochloride, bromodiphenhydramine hydrochloride, chlorcyclizine hydrochloride and diphenylpyraline hydrochloride in aqueous solution has been investigated by light scattering and viscometric methods. The drugs behaved as typical ionic surfactants showing an increase in aggregation number and decrease in critical micelle concentration as the electrolyte concentration was increased over the range 0.05 to 0.154 mol kg−1. A linear relation between log critical micelle concentration and log counterion concentration was established, from which values of the degree of ionization and the free energy of micellization were calculated. The intrinsic viscosity was decreased by the addition of electrolyte and this has been attributed to a decrease in micellar hydration due to a removal of hydrogen-bonded water.
A rapid gas-liquid chromatographic estimation of nicotine in biological fluids
Authors: Feyerabend C , Levitt T , Russell M A H 
Published: April 2011

Abstract
A rapid gas-liquid chromatographic method for the estimation of nicotine in plasma is described. Nicotine is extracted from alkalinized plasma into diethyl ether. This is then concentrated by evaporation and, after an acid back extraction is re-extracted into n-heptane (nitrogen detector) or dichloromethane (flame ionization detector) before injection onto the gas chromatograph. Thirty samples a day can be analysed by this method which enables concentrations of 0.1 ng ml−1 nicotine to be measured. It is thus possible to measure nicotine in plasma and urine samples from non-smokers.
The surface activity of the alveolar lining layer of guinea-pig lung following anaphylaxis
Authors: Goadby P 
Published: April 2011

Abstract
The surface activity and lipid composition of alveolar extracts of guinea-pig lung following anaphylaxis have been studied. The extracts showed a reduced ability to lower surface tension on compression of the surface film which was maximal 30 min after challenge. No significant changes in the lipid content were found but there was a marked increase in the soluble solids 10 min after anaphylactic shock. The significance of these findings is discussed.
Effects of thioridazine and diazepam on the pharmacokinetics of [14C]imipramine in rat: acute study
Authors: Beaubien Arthur R , Mathieu Lise F , Coldwell Blake B 
Published: April 2011

Abstract
The pharmacokinetics of [14C]imipramine (10 mg kg−1) were tested in male Wistar rats for interaction with thioridazine (16 mg kg−1) or diazepam (10 mg kg−1). All drugs were administered orally with the test substances being given 40 min before [14C]imipramine dosing. Bile and urine were collected for 90 min after the radioactive drug was given. The animals were then killed and the tissues removed. Thioridazine reduced the excretion of radioactivity into the bile and urine, and increased the weight of the contents within the gastrointestinal tract. These effects were interpreted as being mainly due to a reduction in gastrointestinal motility resulting in a slower stomach emptying of [14C]imipramine. No effect on metabolism was detected. Diazepam pretreatment reduced the concentration ratio of radioactivity in the small intestinal contents to that of plasma, but did not alter the tissue distribution, metabolism or excretion of [14C]imipramine.
Dopamine receptor blockade and the neuroleptics, a crystallographic study
Authors: Horn Alan S , Post Michael L , Kennard Olga 
Published: April 2011

Abstract
The X-ray structures of 12 drugs of the tricyclic class having varying pharmacological profiles have been examined in detail in an attempt to rationalize the known structure-activity relations of neuroleptic drugs with respect to their ability to block dopamine receptors in the brain. Further evidence is presented in support of the theory that the neuroleptics are able to block dopamine receptors because of a conformational complementarity between certain portions of these drugs and dopamine.
Chemical reactions involved in penicillin allergy: kinetics and mechanism of penicillin aminolysis
Authors: Tsuji Akira , Yamana Tsukinaka , Miyamoto Etsuko , Kiya Emi 
Published: April 2011

Abstract
In view of the fundamental importance of the reaction of penicillins with amino groups of proteins to the penicillin allergy, the aminolysis of benzylpenicillin by various amines was kinetically investigated. The formation rate constants, kamide, of benzylpenicilloylamides were determined at 35°, 45° and 60° (μ = 0·5), and found to obey the general rate law: kamide = k1[amine] + k2[amine H+] [amine] + k3[amine]2 + k4[amine]aOH. All of the amines exhibited the unassisted nucleophilic rate constant, k1. The relative importance of the other kinetic terms depends on the basicity and the chemical structure of amines. The reaction mechanism of penicillin aminolysis was discussed. Brønsted relations for k1, k2 and k3, except for hydrazines, were satisfactory.
A comparison of the effects of morphine and pethidine upon body temperature and the reversal of reserpine's effects upon body temperature in the mouse
Authors: Menon Alexandra M , Pleuvry Barbara J 
Published: April 2011

Abstract
The effects of morphine and pethidine upon body temperature and upon the reversal of reserpine hypothermia in the mouse were investigated. Both morphine and pethidine produced a dose-dependent fall in body temperature, that of morphine being totally antagonized by nalorphine and partially by naloxone, while that of pethidine was antagonised by naloxone and enhanced by nalorphine. Both drugs reversed reserpine-induced hypothermia. The reversal by morphine, but not by pethidine, was partially antagonized by naloxone. Adrenalectomy prevented the reversal of reserpine hypothermia by pethidine but morphine produced a partial reversal. Ganglion blockade and α-and β-blockade all prevented reversal of reserpine hypothermia by both drugs. The results are discussed with regard to differences between pethidine and morphine and possible involvement of opiate receptors.
Methods for study of fluphenazine kinetics in man
Authors: Whelpton R , Curry S H 
Published: April 2011

Abstract
Fluphenazine and its principal metabolites, fluphenazine sulphoxide, and 7-hydroxyflu-phenazine were identified and quantified in human plasma, urine and faeces following intramuscular and oral administration of 14C-fluphenazine dihydrochloride. The presence of a conjugate fraction was also noted. Unmetabolized fluphenazine was selectively extracted into n-heptane. The metabolites were separated by solvent extraction into toluene. Conjugates were hydrolysed back to fluphenazine, fluphenazine sulphoxide and 7-hydroxyfluphenazine. Fluphenazine and fluphenazine conjugates were also measured in the urine of patients receiving long term non-radioactive fluphenazine decanoate therapy. The urinary excretion rate of the conjugate fraction was systematically related to the plasma concentration, regardless of urine flow rate or pH, providing a convenient method for the assessment of fluphenazine kinetics by urinary excretion studies not involving administration of labelled drug.
The adhesion of film coatings to tablet surfaces— instrumentation and preliminary evaluation
Authors: Fisher D G , Rowe R C 
Published: April 2011

Abstract
The strength of the adhesive bond between a film coating and a tablet surface has been studied using a specially designed tensile testing apparatus. The adhesion has been taken as the force require to remove the film from unit area of the tablet surface and has been shown to be dependent on the compression pressure used to prepare the tablet and on changes in the film formulation. Although plasticizers did not show any significant effect on the adhesion of a hydroxypropyl methylcellulose film, a reduction of 45 % was found on the addition of 10 % w/w titanium dioxide.
Size analysis of suspension inhalation aerosols by inertial separation methods
Authors: Hallworth G W , Andrews U G 
Published: April 2011

Abstract
The particle size distribution of beclomethasone dipropionate (BDP) aerosols delivered from pressurized metered dose suspension inhalers has been measured with three cascaded inertial separation instruments, the Casella Cascade Impactor, Multistage Liquid Impinger and Cascade Centripeter. Various methods for collecting the emitted aerosol before measurement have been examined. A bent glass tubular ‘throat’, used as a simulated oro-pharynx, collects 35–60 % of the emitted dose by impingement of the wet spray cone in the throat. The aerosol passing through the throat has a similar but somewhat finer size distribution to that collected by firing directly into a large flask. The three cascaded instruments give similar results which in the Multistage Liquid Impinger also resemble those given by a salbutamol inhaler. The mass fraction (35–60%) emitted from the oral adaptor which is of a size capable of deep lung penetration (&lt;4 μm) is much higher than the fraction (10–16%) found in the lungs of dogs after inhalation of aerosol. The size distributions resemble those determined by microscopy and are expressed as aerodynamic sizes, thus showing that the particles approximate to unit density spheres. The performance of two simpler devices, Kirk's apparatus and the Harwell size selective air sampler are also assessed, the latter shows some promise for the simple evaluation of the respirable fraction of inhalation aerosols.
The influence of crystal form on the radial stress transmission characteristics of pharmaceutical materials
Authors: Summers M P , Enever R P , Carless J E 
Published: April 2011

Abstract
Various crystal forms of sulphathiazole, barbitone and aspirin were compressed in a single-punch tablet machine instrumented to monitor axially applied and radially transmitted forces, and upper punch movement. The changes in radial stress during the compression cycle depended upon the polymorphic form of the compressed material. The results were rationalized in terms of the degree of plastic flow/crushing that occurred with each material, and the degree to which the final compact underwent elastic compression. It is postulated that the reduction in the transition temperature of polymorphic forms of sulphathiazole and barbitone and the polymorphic transition of sulphathiazole Form II was due to the production of dislocations in the crystal and the distortion of the crystals at crystal boundaries formed in the compressed materials.
The transport of tetracyclines across the mouse ileum in vitro: the effect of cations and other agents
Authors: Banerjee Sachchidananda , Chakrabarti Kalyan 
Published: April 2011

Abstract
The intestinal transfer of different tetracyclines dissolved in calcium-and magnesium-free Krebs bicarbonate buffer solution, pH 7·4, was studied using the everted ileum of the mouse. The rates of transfer of chlortetracycline and demethylchlortetracycline were less than those of tetracycline and oxytetracycline, the latter compounds being transferred at the same rate. Addition of calcium and magnesium to the buffer greatly reduced the transfer of tetracycline; this inhibition could be antagonized by EDTA. The presence of iron also inhibited the transfer of tetracycline. The inhibitory effect of these ions on tetracycline transfer seemed due to chelation of the drug. Glucosamine and acetylmethionine, but not acetyl glucosamine, diminished the intestinal transfer of tetracyclines. The former two agents did not influence the uptake of tissue fluids. Tetracycline was also transferred from the serous to the mucous coat in the non-everted intestinal sac of mice. The above observations suggested that the absorption of tetracyclines was not due solely to passive diffusion.
Intestinal pH and propulsion: an explanation of diarrhoea in lactase deficiency and laxation by lactulose
Authors: Bennett Alan , Eley Kenneth G 
Published: April 2011

Abstract
Acidification of the lumen of guinea-pig isolated intestine increases peristaltic activity. A low colonic pH might therefore contribute directly to the diarrhoea induced by lactose in lactase-deficient subjects, and to the laxative effect of lactulose.
Influence of non-ionic surfactants on permeation of hydrocortisone, dexamethasone, testosterone and progesterone across cellulose acetate membrane
Authors: Barry B W , Eini D I D El 
Published: April 2011

Abstract
The lag-time method of diffusion has been used to investigate permeation of hydrocortisone, dexamethasone, testosterone and progesterone across cellulose acetate membranes between 10° and 40°. The process depended mainly on membrane-water partition coefficients of the steroids so that the least polar compound permeated the fastest. Permeation generally increased with increasing temperature and from the temperature dependance of the diffusion coefficient, energies of activation were derived. These varied from 2·4 kcal mol−1 for the least polar steroid, progesterone, to 7·4 kcal mol−1 for the most polar, hydrocortisone, n - C16 Polyoxyethylene surfactants when present below and above the cmc increased the steroids permeation rates. Varying the polyoxyethylene chain length (OE = 17–63) did not significantly affect permeation rates, suggesting that the enhancing effect of surfactants arises from their hydrophobic group.
The effect of cholinesterase inhibitors on the antimuscarinic effect of hemicholinium-3 (HC-3) in the rat
Authors: Hecker S E , Mitchelson F 
Published: April 2011

Abstract
The effect of hemicholinium-3 (HC-3) on responses of the rat isolated bladder and ileum to acetylcholine and carbachol was investigated in the absence and presence of a number of anticholinesterases. Responses of the bladder to acetylcholine were potentiated by DFP, edrophonium, BW284C51 and physostigmine but were unaffected by the specific butyrylcholinesterase inhibitor iso-OMPA. Responses to carbachol were not potentiated by the anticholinesterases. HC-3 (1·7 × 10−4m) inhibited responses to carbachol without affecting those to acetylcholine. In the presence of physostigmine or DFP responses to acetylcholine were inhibited by HC-3 but no such inhibition was observed in the presence of BW284C51, edrophonium or iso-OMPA or a combination of the latter two anticholinesterases. Responses to carbachol were also inhibited to a greater extent in the presence of DFP. In the ileum, responses to acetylcholine were increased in the presence of DFP, edrophonium and physostigmine but were unaffected by iso-OMPA. Responses to carbachol were not increased by any of the anticholinesterases. HC-3 (2·8 × 10−4 m) inhibited responses to both acetylcholine and carbachol in the ileum and the degree of inhibition was not significantly altered by the presence of any of the anticholinesterases used.
Although a weak anticholinesterase, HC-3 was also found to decrease the inhibitory action of physostigmine on the hydrolysis of acetylcholine by homogenates of rat ileum. A similar effect was noted with DFP but not with edrophonium.
The results obtained do not support a prejunctional action for HC-3 in antagonizing responses to carbachol. It is concluded that in addition to an inhibitory action on the postjunctional muscarinic receptor HC-3 may interfere with the anticholinesterase activity of some cholinesterase inhibitors such as physostigmine and DFP but not edrophonium.
Characterization of moisture interactions in some aqueous-based tablet film coating formulations
Authors: Okhamafe Augustine O , York Peter 
Published: April 2011

Abstract
Three methods—radiotracer, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)—have been employed to evaluate moisture interactions in aqueous-based hydroxypropyl methylcellulose films containing polyethylene glycol 400, polyethylene glycol 1000 or polyvinyl alcohol. The radiotracer employed was tritiated water. Using a proposed classification, the water present in the films was placed in three categories: tightly bound, moderately bound and free. The tightly bound water in hydroxypropyl methylcellulose and hydroxypropyl methylcellulose/polyvinyl alcohol films was related to the crystallinity of the films whilst tightly bound water was practically non-existent in the plasticized systems thus indicating the absence of crystallinity. Free (or freezable) water could not be detected in the films using DSC. The moisture content data obtained by TGA were considered to represent moderately bound water. The moderately bound water content of the film systems was in the rank order of the hydrophilicity of the polymer additives: polyethylene glycol 400 &gt; polyethylene glycol 1000 &gt; polyvinyl alcohol. This order was reversed for the calculated free water content.
The effect of proadifen on the metabolism of adinazolam
Authors: Sethy Vimala H , Francis Jonathan W , Day Jeffrey S 
Published: April 2011

Abstract
Binding affinities of adinazolam and its metabolite mono-N-demethyladinazolam, U-42352, to the brain tissue are not altered by the presence of proadifen (SKF-525A) in [3H]flunitrazepam ([3H]FNZ) binding assays in-vitro. Pre-treatment of mice with proadifen significantly blocked the ability of intravenously administered adinazolam to inhibit [3H]FNZ binding in the studies ex-vivo. The binding profile of [3H]FNZ to the brain tissue was not significantly different when animals were treated with U-42352 or proadifen with U-42352. These results suggest that proadifen may block the conversion of adinazolam to its active metabolite U-42352.