bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of the mitochondrial oxidation of octanoate by salicylic acid and related compounds
Authors: Graham A B , Park M V 
Published: April 2011

Abstract
The inhibition of mitochondrial octanoate oxidation in vitro by salicylic acid (1mm), 2,4-dinitrophenol (0·05mm) and γ-resorcylic acid (2mm) was studied. Concentrations of salicylate and 2,4-dinitrophenol markedly inhibiting the mitochondrial oxidation of octanoate did not significantly affect the mitochondrial oxidation of octanoylcarnitine. All three compounds (0·4mm) inhibited a partially purified preparation of medium chain-length acyl-CoA synthetase from ox liver mitochondria. It is suggested that at least part of the ininhibition of mitochondrial oxidation by salicylic and γ-resorcylic acids in vitro in the concentration ranges studied is caused by the direct inhibition of the medium chain length acyl-CoA synthetase.
Influence of an acetylsalicylic anhydride impurity on the rate of dissolution of acetylsalicylic acid
Authors: Bundgaard Hans 
Published: April 2011

Abstract
The intrinsic dissolution rate of acetylsalicylic acid in 0·1 n hydrochloric acid at 35° has been shown by a rotating disc method to be affected by the presence of acetylsalicylic anhydride in the crystals. At concentrations exceeding 0·25% the impurity decreased the dissolution rate of the acetylsalicylic acid. It is suggested that the previously reported differences in rates of dissolution of various commercial and recrystallized acetylsalicylic acid preparations may be due to differences in content of acetylsalicylic anhydride which is a frequently-occurring impurity in commercial acetylsalicylic acid and is formed on heating solutions of acetylsalicylic acid in various organic solvents.
Phase studies of mixed phosphated surfactants, n-hexane and water
Authors: Groves M J , Mustafa R M A , Carless J E 
Published: April 2011

Abstract
Mixtures of phosphated nonylphenolethoxylate (PNE), phosphated fatty alcohol ethoxylate (PFE) and n-hexane form ‘oils’ which may spontaneously emulsify when added to water. However, the degree of spontaneity and the stability of the resulting dispersions vary according to the constitution of the system. Studies of the equilibrium phase diagrams suggest that the anomalies may be attributed to the presence of liquid crystalline phases of different types which are formed in the presence of water.
Computer analysis of multicomponent ultraviolet spectra
Authors: Madsen B W , Herbison-Evans D , Robertson J S 
Published: April 2011

Abstract
In the assay of multicomponent systems by ultraviolet spectrophotometry, it is possible to improve accuracy and precision and also to obtain various statistical criteria by considering data over the range of wavelengths concerned. A linear least squares approach has been programmed to analyse mixtures of drugs in the presence or absence of known background. When the background was unknown but could be assumed of simple form, a non-linear alternative was successful.
Mechanism of induction of hepatic microsomal drug metabolizing enzymes by a series of barbiturates
Authors: Ioannides Costas , Parke Dennis V 
Published: April 2011

Abstract
The inducing effect of certain barbiturates (secobarbitone, thiopentone, pentobarbitone, allobarbitone, phenobarbitone and barbitone) on the levels of the hepatic microsomal drug-metabolizing enzymes has been studied in the rat both in vivo and in vitro. The extent of induction was related to the plasma half-lives of the barbiturates; compounds with low rates of metabolism and long half-lives were the most potent inducing agents. The latter (phenobarbitone, pentobarbitone and allobarbitone) were shown by spectral technique to interact with cytochrome P-450 suggesting that their mechanism of enzyme induction was ‘substrate induction’ in type. Barbiturates containing an allyl group (secobarbitone and allobarbitone) had a weaker inducing effect than expected, possibly due to their destruction of cytochrome P-450. Despite its short plasma half-life of 0·5 h thiopentone was a relatively potent inducer probably due to its metabolism to pentobarbitone, which has a much longer plasma half-life (1·3 h). Barbitone is an effective inducer of the drug-metabolizing enzymes, yet does not interact spectrally with cytochrome P-450; this is in accord with the observations that although there are increases in NADPH-cytochrome c reductase and cytochrome b5, following administration of barbitone there is no increase in cytochrome P-450. Barbiturate pretreatment does not affect the activities of glucose-6-phosphatase, glucose-6-phosphate dehydrogenase or 6-phosphogluconate dehydrogenase.
The influence of polyvinylpyrrolidone on the dissolution properties of hydroflumethiazide
Authors: Corrigan O I , Timoney R F 
Published: April 2011

Abstract
The incorporation of hydroflumethiazide with polyvinylpyrrolidone (PVP) was found to retard and to enhance the dissolution of the drug from compressed discs, the magnitude of the effect being dependent on the proportion of PVP present and its method of incorporation. The most active system dissolved sixteen times faster than pure hydroflumethiazide. Low concentrations of PVP were also found to decrease the apparent solubility of hydroflumethiazide while at high concentrations solubility was enhanced. X-ray and infrared analysis of systems suggested the presence of an amorphous form of hydroflumethiazide in coprecipitate systems. The dissolution data were consistent with a physical model which takes account of the roles played by crystalline and amorphous hydroflumethiazide together with the complexing and crystal growth inhibiting effect of PVP on hydroflumethiazide.
Effects of hardness on the disintegration time and the dissolution rate of uncoated caffeine tablets
Authors: Kitazawa Shikifumi , Johno Ikuo , Ito Yoko , Teramura Shigeo , Okada Jutaro 
Published: April 2011

Abstract
The effects of hardness on disintegration and dissolution characteristics of uncoated caffeine tablets made at eight different pressure levels were studied. The disintegration times were determined using the J.P. VIII procedure with disks and the dissolution rate measurements were performed with the U.S.P. XVIII procedure (U.S.P. method) and the J.P. VIII disintegration test apparatus (J.P. method). A good correlation between the hardness and the disintegration times was obtained. The dissolution rate constants were determined from the equation of Noyes & Whitney (1897) and a good correlation between the hardness and the dissolution rate constants was obtained. The hardness governed the dissolution over all the stages from tablet to the smallest particles after the breakage by disintegration. The dissolution rates of the J.P. method were greater than those of the U.S.P. method.
Some effects of pilocarpine and acetylcholine on the responses of the guinea-pig vas deferens to hypogastric nerve stimulation and transmural stimulation and applied (–)-noradrenaline
Authors: Lamble Andrea P , Lamble J W 
Published: April 2011

Abstract
Enhancement by acetylcholine and by pilocarpine of the contractile responses of the guinea-pig isolated vas deferens to hypogastric nerve and transmural stimulation and to exogenous (–)-noradrenaline was examined. At high concentration (600 nm) acetylcholine enhanced responses in the order: hypogastric nerve &gt; transmural &gt; exogenous (–)-noradrenaline. Pilocarpine produced a similar maximal degree of enhancement with all three stimuli. All these effects were reversibly inhibited by 1.4 μta atropine, a concentration which alone did not affect responses to the stimuli. Pilocarpine (50–400 μm) gave a concentration-related inhibition of the enhancement of responses to hypogastric nerve stimulation by 600 nm acetylcholine.
The pharmacology of Avena sativa
Authors: Connor J , Connor T , Marshall P B , Reid A , Turnbull M J 
Published: April 2011

Abstract
The pharmacology of Avena sativa has been investigated in laboratory animals following a report that tincture of Avena sativa reduced the craving for cigarettes in man. The tincture, evaporated to dryness, re-constituted in an equal volume of water and administered by stomach tube or intraperitoneal injection, antagonized the antinociceptive effect of morphine in two separate tests (hot-plate and tail flick). Compared with animals made dependent on morphine alone, mice pretreated with repeated injections of morphine plus extract passed a smaller number of stools and tended to jump less after administration of nalorphine. The pressor response to intravenously administered nicotine in urethane-anaesthetized rats was also antagonized by prior administration of Avena sativa. However, the aqueous extract prepared from the tincture did not affect the seizure threshold to bemegride or nicotine or the sleeping time induced by barbitone sodium.
Effects of a human plasma fraction on leucocyte migration into inflammatory exudates
Authors: Ford-Hutchinson A W , Smith M J H , Elliott P N C , Bolam J P , Walker J R , Lobo A A , Badcock J K , Colledge A J , Billimoria F J 
Published: April 2011

Abstract
A fraction prepared from normal human plasma inhibits the migration of polymorphonuclear and mononuclear leucocytes into inflammatory exudates produced by the intrapleural injection of carrageenan or turpentine and by the subcutaneous implantation of polyvinyl sponges in the rat. The mechanism of the effect does not involve complement depletion.
Effect of pregnenolone-16α-carbonitrile (PCN) on drug response in man
Authors: Szabo S , Komlos S , Ignjatovic Z 
Published: April 2011

Abstract
Pregnenolone-16α-carbonitrile (PCN), which alters drug responses and induces hepatic microsomal drug-metabolizing enzymes in experimental animals, is well-tolerated in man. There were no marked changes in the concentrations of blood sugar and urea; bromsulphophthalein (BSP) clearance; serum alkaline phosphatase activity; hematocrit, erythrocyte and leukocyte counts; as well as in ecg patterns. When the steroid was given by mouth for 4 days to patients treated with electroshock for psychiatric disorders, it decreased suxamethonium-induced skeletal muscle fasciculation and shortened thiopentone as well as propanidid anaesthesia. Breathing was resumed more rapidly than in control subjects. The protective effect of PCN is probably mediated through induction or activation of hepatic drug-metabolizing enzymes, or both.
The solubilization of some local anaesthetic esters of p-aminobenzoic acid by lysophosphatidylcholine
Authors: Hunt M J , Saunders L 
Published: April 2011

Abstract
The solubilization by lysophosphatidylcholine (LPC) of three n-alkyl esters of p-aminobenzoic acid has been studied. These esters have a local anaesthetic action. Quantitative studies show that the amount of compound solubilized is proportional to the LPC concentration and that solubilization increases in the order ethyl, n-propyl and n-butyl ester. 100MHz nmr studies indicate that the local anaesthetic esters are solubilized in the hydrocarbon interior of the LPC.
The influence of cosolvents and substrate substituents on the sorption of benzoic acid derivatives by polyamides
Authors: Richardson N E , Meakin B J 
Published: April 2011

Abstract
The sorption of some substituted benzoic acid derivatives by polyamides (nylons) from aqueous solution has been examined and the influence of their nature together with those of the cosolvent and polymer have been assessed. In all cases the sorption isotherms were linear and could be expressed by a simple distribution law, enabling the influence of cosolvent concentration to be predicted. The sorption of a series of p-substituted benzoic acids and some of their esters is related to their solubility except where the p-substituent is capable of hydrogen-bonding with the polymer. The extent of the interaction is also dependent upon the amide frequency of the polymer.
Isolation, characterization and quantitation of chloral hydrate as a transient metabolite of trichloroethylene in man using electron capture gas chromatography and mass fragmentography
Authors: Cole W J , Mitchell Rosemary G , Salamonsen R F 
Published: April 2011

Abstract
A method for the quantitative determination of plasma concentrations of chloral hydrate by electron capture gas chromatography is described. Characterization by multiple ion monitoring confirms, for the first time, that chloral hydrate exists as a transient metabolite of trichloroethylene in man.
Comparison of the time course of the anorectic effect of fenfluramine and amphetamine with drug levels in blood
Authors: Blundell J E , Campbell D B , Lesham M , Tozer R 
Published: April 2011

Abstract
Time courses of the suppressive effects on food intake of (+)-amphetamine and (±)-fenfluramine in deprived rats were found to be different. Amphetamine displayed a potent initial action which rapidly decayed, and this behavioural effect was consistent with the measured blood concentration of amphetamine which showed a peak at 1 h followed by rapid clearance. For fenfluramine, the initial suppression of eating was maintained over several hours and was, for the first hour, related to the blood concentration of fenfluramine but later to an active metabolite, norfenfluramine. The study shows how drug-induced changes in feeding behaviour fluctuate over time and illustrate how single measures of food intake may overlook information about the effectiveness of anorectic drugs.
How does angiotensin II increase cardiac dopamine-β-hydroxylation?
Authors: Chevillard Claude , Duchene Nicole , Alexandre Jean Michel 
Published: April 2011

Abstract
The potent accelerating effect of angiotensin II (Ang II) on cardiac dopamine β-hydroxylation was studied on slices of rat heart. Ang II did not affect the kinetics of β-hydroxylation but it increased the axonal uptake of dopamine, and, concomitant with the acceleration of biosynthesis, it enhanced the accumulation of dopamine into tissue. Puromycin, in contrast to actinomycin D, antagonized the stimulation of dopamine β-hydroxylation by Ang II, but did not suppress the rise in cardiac dopamine. Therefore, to promote the acceleration of dopamine β-hydroxylation, (i) the rise in tissue dopamine available for conversion appeared to be insufficient, (ii) the formation of new proteins by activation of traduction seemed to constitute the basic mechanism of Ang II action.
Some relations between dissolution rates and physical parameters of a drug in aqueous micellar solutions of a non-ionic surfactant
Authors: Collett J H , Rees Judith A 
Published: April 2011

Abstract
Dissolution rates of salicylic acid from a constant surface area into a series of aqueous micellar polysorbate 20 solutions at pH 1·0 to 4·0 have been measured using two different methods; a stirred beaker and a rotating disc technique. The micellar molecular weight of polysorbate 20 has been obtained from light scattering and differential refractometry data and used with other independently determined physical data to calculate diffusion coefficients of the diffusing species. Linear multiple regression analysis was used to assess the dependence of drug dissolution rate on the diffusion coefficient and the viscosity of the dissolution medium.
The effect of ageing on the rheological properties of gelatin gels
Authors: Robinson John A J , Kellaway Ian W , Marriott Christopher 
Published: April 2011

Abstract
The effect of ageing at 4° on the viscoelastic properties of 1·5 and 2·0% acid and alkaline processed gelatin gels has been investigated. Viscoelastic properties were not markedly affected by ageing time although evidence of a decrease in gel structure with increasing ageing time was apparent. This has been tentatively attributed to hydrolysis of amide links. 1·5% alkaline gels were shown to be more rigid than the corresponding acid gels and this has been discussed in terms of differences in molecular weight, polydispersity, charge and charge distribution.
Locomotor activity stimulation in rats produced by dopamine in the nucleus accumbens: potentiation by caffeine
Authors: Andén Nils-Erik , Jackson David M 
Published: April 2011

Abstract
The increased motor activity of reserpine-nialamide pretreated rats given dopamine into the nucleus accumbens was potentiated in a dose-dependent manner by systemically administered caffeine. Similarly, the increase in motor activity seen when the endogenous dopamine was released by intraperitoneally administered amphetamine was potentiated by systemically given caffeine. These effects might be due to an increase in the dopamine-induced accumulation of cyclic AMP in the nucleus accumbens after inhibition of the phosphodiesterase by caffeine.
The in vitro adsorption of drugs from horse serum onto carbon coated with an acrylic hydrogel
Authors: Kolthammer J 
Published: April 2011

Abstract
In vitro studies have shown that uncoated carbon and carbon coated with an acrylic hydrogel are capable of adsorbing drugs from horse serum at 37°. Increase in the coating weight from 2 to 4% decreased the rate of adsorption but not the total capacity. In vivo data supports the concept of carbon haemoperfusion for use in the treatment of drug overdose.
Inhibition of drug-induced anorexia in rats by methysergide
Authors: Barrett A M , McSharry Lesley 
Published: April 2011

Abstract
Iproniazid was found to reduce food consumption in fasting rats. Combined treatment of iproniazid with tryptophan resulted in a significantly greater anorexic action whilst tryptophan alone had no effect on food consumption. Iproniazid treatment was associated with a significant increase in brain 5-hydroxytryptamine (5-HT) concentration but in association with tryptophan higher brain 5-HT concentrations were recorded. The anorexic action of the iproniazid-tryptophan combination was antagonized in a dose-dependent fashion by methysergide. Equivalent levels of anorexia induced by fenfluramine and mazindol were similarly antagonized by methysergide in a dose-related manner. The results suggest a common role of 5-HT in the inhibition of eating behaviour in fasting rats when anorexia is induced by iproniazid, fenfluramine or mazindol, sensitive to a specific 5-HT antagonist.
The effect of an aldosterone antagonist on the protective action of carbenoxolone on the gastric mucosal barrier
Authors: Rees W D W , Rhodes J , Cross S , Hole D 
Published: April 2011

Abstract
The effect of an aldosterone antagonist on the protective action of carbenoxolone sodium on the gastric mucosal barrier has been studied in three dogs with Heidenhain pouches. The net fluxes of hydrogen ion and sodium ion were measured before, during, and after contact with a 10 mm bile acid solution at pH 2, in pouches which had not been treated with drugs, in pouches treated with carbenoxolone sodium and in pouches treated with both carbenoxolone sodium and the aldosterone antagonist, spironolactone.
Hydrogen ion back diffusion from, and sodium ion gain by the untreated pouch was increased by 10 mm bile acid solution. Addition to the pouches of either carbenoxolone sodium alone or carbenoxolone sodium and spironolactone reduced the hydrogen ion back diffusion after exposure to the bile acid solution. The spironolactone did not change the protective effect of carbenoxolone on the gastric mucosal barrier. Carbenoxolone did not change the increased sodium ion diffusion caused by bile.
The bioavailability in man of ICRF-159 a new oral antineoplastic agent
Authors: Creaven Patrick J , Allen Larry M , Alford Dorothy A 
Published: April 2011

Abstract
The bioavailability of the antineoplastic agent, ICRF-159, has been examined in 12 patients receiving the drug in single and subdivided dose schedules in an attempt to account for the differences in toxicity found with the different schedules clinically. Recovery of radioactivity in the urine after single large doses (13·3–19·4 g) was 8·5 ± 3·0% of the administered dose. After doses of 3·8–5·55 g recovery was 22·7 10±5% and after the same dose subdivided into 3 equal aliquots it was 52 ± 8·7%. Unrecovered radioactivity was largely accounted for in the faeces. Plasma radioactivity levels in 2 patients after high and low dose were equivalent. Toxicity of the drug paralleled urinary recovery of radioactivity. It is concluded that schedule dependence of toxicity of ICRF-159 is at least partly due to bioavailability factors.
A rapid g.l.c. procedure for the determination of codeine and norcodeine in biological fluids based on micro-phase extraction techniques
Authors: Serfontein Willem J , Botha Deo , de Villiers Louis 
Published: April 2011

Abstract
Therapeutic serum concentrations of codeine can be virtually completely extracted and obtained sufficiently concentrated for g.c. measurement without distillation, by acid extraction of the drug from the initial crude organic extracts of alkalinized serum followed by a micro-phase back extraction step. The procedure has simplicity, rapidity and eliminates concentration by distillation and background interference. The method can be readily adapted for the separate measurement of codeine and norcodeine and it can also be used for similar analyses of other body fluids.
The determination of thebaine in Papaver bracteatum Lindl by gas-liquid chromatography
Authors: Fairbairn J W , Helliwell K 
Published: April 2011

Abstract
Several solvents have been examined in the process of developing a convenient method for extracting powdered material and removing interfering pigments to produce an extract of Papaver bracteatum suitable for g.l.c. assay. The most suitable extracting solvent was aqueous acetic acid (5%); the assay method gave satisfactory reproducibility with a wide range of plant materials (coefficient of variation 0.63 to 3.33 %). The accuracy was checked by recovery experiments with pure thebaine and by examination of exhausted marcs. The presence of other alkaloids did not interfere with the assay. There were substantial differences in the amounts of thebaine extracted from capsule and root samples by ammoniacal methanol and by aqueous acetic acid, indicating the presence of thebaine in a “bound” form. The minimum amount of thebaine that could readily be determined by the g.l.c. method was 0.3 mg in the sample of powder used for the assay.
A model for steroid transport across biological membranes
Authors: Beckett A H , Pickup M E 
Published: April 2011

Abstract
The absorption of a range of steroids (water soluble to lipid soluble) in the mouth was investigated under standard conditions and using gas chromatography. A two-compartment open model was used to describe the absorption of these steroids into, and through, the membrane. Rate constants were calculated on this basis using a feathering technique, and were used in an analogue computer program to predict steroid concentration which agreed favourably with experimental data. Correlations between absorption and partition data were made in an attempt to relate the proposed model to anatomical features of the absorptive membrane and to make comparison with models proposed to describe drug absorption across the intestinal mucosa.
Investigation of changes in the lipid content of guinea-pig lung after anaphylaxis
Authors: Goadby P 
Published: April 2011

Abstract
A detailed analysis of the lipid content of guinea-pig lung following anaphylaxis in vivo induced by aerosolized antigen snowed a significant reduction in all fractions. Anoxia induced by nitrogen produced reductions in the partial glycerides and ethanolamine phospholipid. Exposure to an aerosol of histamine caused a reduction in all but the choline phospholipid and sphingolipid fractions. It was concluded that the losses of choline phospholipid and sphingolipid result from the anaphylactic reaction and not from subsequent changes.