bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dissolution rate studies using the B.P. disintegration apparatus
Authors: KHALIL SALEH A H , ALI L M M , KHALEK M M ABDEL 
Published: April 2011

Abstract
The application of the B.P. disintegration apparatus in dissolution rate studies has been examined. The dissolution profiles of some brands of chloramphenicol capsules and tolbutamide tablets have been examined at various tube speeds with and without the guided disc. For both drugs a tube speed of 20 strokes/min gave the optimum difference in dissolution rates. The effect of the guided disc depended on the disintegration time of the product tested. For poorly disintegrating products the use of the guided disc resulted in about twofold increase in dissolution whilst insignificant effect was found for products with fast dissolution rate.
The protective effect of gallate antioxidants on emulsions and solutions of benzaldehyde
Authors: NIXON J R , HAQUE R S UL , CARLESS J E 
Published: April 2011

Abstract
In solubilized systems of benzaldehyde-water-antioxidant-cetomacrogol the ratio of benzaldehyde to gallate antioxidant is of prime importance. Provided this ratio is constant, the rate of oxidation and the induction period of the systems is independent of cetomacrogol concentration. The efficiency of the different gallates appears to be the same in L1 micellar systems. In disperse systems the maximum oxidation rate is related to the total surface area of the droplets and to the quantity of benzaldehyde present in the disperse phase. Because changes in the relative concentration of the components of the system alter both the phase volume ratio and the total surface area a protection factor concept (ratio of the rate of oxidation of benzaldehyde in the absence of gallate: rate in the presence of gallate) was used to define the effect of gallates on the maximum rate.
The role of cyclic AMP in isoprenaline-induced cardiac necroses in the rat
Authors: MARTORANA P A 
Published: April 2011

Abstract
Single administrations of isoprenaline chloride (6–36 μg/kg, s.c.) resulted in the appearance of acute myocardial necroses in the rat within 24 h. The percentage of animals with lesions was directly related to the dose of isoprenaline. Dibutyryl cyclic AMP (1–50 mg/kg, i.p.) induced myocardial lesions of the same type, however the percentage of animals affected was not dose-dependent. Pretreatment with theophylline (75 mg/kg, s.c.) administered to inhibit cardiac phosphodiesterase activity, induced a 48-fold reduction in the ED50 of isoprenaline and potentiated the nucleotide-induced cardiac lesions which became dose-dependent. Thus, a mediatory role for cyclic AMP in the isoprenaline-induced cardiac necroses in the rat is suggested.
Mechanism of MJ 1999-induced blockade of neuromuscular transmission
Authors: PATEL V K , KELKAR V V , JINDAL M N 
Published: April 2011

Abstract
MJ 1999 [4-(isopropylamino-1-hydroxyethyl)methanesulphonanilide hydrochloride] produced a dose-related blockade of indirectly evoked twitches of the rat diaphragm, without materially altering the effects of direct stimulation. The magnitude of blockade was comparable whether the indirect stimulation was at 1/s or 1/20 s. The blockade was less pronounced at 25° than at 34°. The blockade was antagonized by neostigmine, potassium chloride, succinyl-choline, tetraethylammonium, adrenaline, isoprenaline and, to some extent, by noradrenaline. Blockade by MJ 1999 was additive to that due to tubocurarine; large concentrations of yohimbine, tolazoline, phenoxybenzamine and dihydroergotamine quickly antagonized MJ 1999 blockade. Small concentrations of adrenaline, isoprenaline, tolazoline or yohimbine prevented MJ 1999 blockade. MJ 1999 had no effect on nerve conduction. It is proposed that MJ 1999 has a two-fold mode of action at the neuromuscular junction; a curare-like effect and an action on β-receptors.
The effect of heat, pH and some buffer materials on the hydrolytic degradation of sulphacetamide in aqueous solution
Authors: MEAKIN B J , TANSEY I P , DAVIES D J G 
Published: April 2011

Abstract
The hydrolytic degradation of sulphacetamide has been investigated under anoxic conditions over a wide range of pH values and at different temperatures. The sole breakdown product is sulphanilamide. The reaction is essentially independent of pH (measured at 25°) over the range 5 to 11, but is subject to catalysis by buffer constituents. Below pH 4 specific hydrogen ion catalysis occurs. Calculation of activation parameters leads to the conclusion that sulphacetamide solutions can be satisfactorily autoclaved provided they are not subsequently refrigerated.
Demonstration of 3,4-dihydroxy[14C]benzoic acid and [14C]vanillic acid after administration of [14C]noradrenaline in the rat
Authors: PESKAR B , HELLMANN G , HERTTING G 
Published: April 2011

Abstract
Rats were injected with 40 μCi (±)-[1-3H]noradrenaline and 10 μCi ±-[1-14C]noradrenaline. Three fractions with a decreased 3H:14C ratio were isolated from the urine by a combined alumina adsorption-ethyl acetate extraction procedure. Two of the fractions were identified as [14C]vanillic acid and 3,4-dihydroxy[14C]benzoic acid, respectively. Vanillic acid represented between 1.5 and 3.0% of the total [14C]activity excreted within 24 h and the contribution of dihydroxybenzoic acid was 0·2-0·5%. The third fraction with a decreased 3H: 14C ratio has not been identified and represented about 2% of the total [14C]activity excreted within 24 h. After monoamine oxidase blockade with 100 mg/kg of iproniazid, the excretion of vanillic acid, 3,4-dihydroxybenzoic acid and the unknown fraction was greatly diminished. The probability that these three substances represent those metabolites arising simultaneously with the formation of tritium water from (±)-[1-3H]noradrenaline is discussed.
A phase-rule study of multiple-phase formation in a model emulsion system containing water, n-octanol, n-dodecane and/a non-ionic surface-active agent at 10 and 25°
Authors: MARLAND J S , MULLEY B A 
Published: April 2011

Abstract
A four-component emulsion system containing the non-ionic surfactant C8H17 (O·CH2·CH2)6OH has been investigated, particularly in regions in which liquid crystal or more than two condensed phases are formed. Liquid crystal does not exist in the binary surfactant-water system at 25° but extensive regions form when the organic liquids octanol and dodecane are present, although these are not joined to the main two-liquid regions of the emulsion system. The surfactant is almost completely dissolved in the aqueous phase in water-dodecane mixtures but when substantial amounts of octanol are also present the partition coefficient is reversed in favour of the organic phase. At certain intermediate compositions three liquid phases are present. The significance of these results to the system as an emulsion are briefly discussed.
The kinetics of dissolution for a non-disintegrating standard substrate
Authors: WITHEY R J 
Published: April 2011

Abstract
The dissolution profiles for a 1 cm sodium chloride cube, which was considered to represent a standard non-distintegrating substrate, were obtained in seven kinds of dissolution apparatus. The results were used to assess experimental reproducibility and apparatus variables and to examine the adherence of the kinetics of the dissolution process to theoretical rate laws.
The mechanism of the inhibitory action of salicylate on glutamyl-transfer ribonucleic acid synthetase in vitro
Authors: BURLEIGH MARY , SMITH M J H 
Published: April 2011

Abstract
Salicylate inhibits glutamyl-transfer ribonucleic acid synthetase by simple competitive inhibition with respect to glutamate and mixed competitive-non-competitive inhibitions with ATP and tRNA. It is suggested that competition between salicylate and amino-acid explains the variable inhibition of the synthetases by the drugs in vitro. The action of salicylate is consistent with a mechanism for glutamyl-tRNA formation involving a concerted interaction of all three substrates. The drug may selectively interfere with protein synthesis in vivo.
The neuromuscular blocking activity of some monoquaternary androstane derivatives
Authors: BAMFORD D G , BIGGS D F , DAVIS M , PARNELL E W 
Published: April 2011

Abstract
The neuromuscular blocking activity of some 3- or 17-monoquaternary derivatives of 3β,17β-dipyrrolidin-1′-yl-5α-androstane has been examined in the cat. 3-Monoquaternary salts were, in general, more potent than the 17-monoquaternary salts. It was concluded that the presence of a quaternary group in position 3 is an important determinant of potency in this series of androstane derivatives.
Some 5-hydroxytryptamine-like actions of fenfluramine: a comparison with (+)-amphetamine and diethylpropion
Authors: SOUTHGATE P J , MAYER SUSAN R , BOXALL ELIZABETH , WILSON A B 
Published: April 2011

Abstract
The 5-hydroxytryptamine (5-HT)-like effects of fenfluramine have been investigated in mice in two different experiments. In a behavioural test in mice pretreated with tranylcypromine, fenfluramine caused stereotyped changes which were similar to those produced by 5-hydroxytryptophan (5-HTP) and were antagonized by methysergide or pretreatment with p-chlorophenylalanine (PCPA). Like 5-HTP, fenfluramine reduced the conditioned response in a one-trial conditioning test, an effect antagonized by methysergide or by PCPA pretreatment. The reduction in the conditioned response caused by a maximal electroconvulsion was also antagonized by PCPA, an effect prevented by 5-HTP. Equivalent anorectic doses of (+)-amphetamine and diethylpropion caused a small increase in stereotyped behaviour, but this was not modified by methysergide; both anorectic drugs were inactive in the one-trial conditioning test. It seems probable that the observed actions of fenfluramine are caused indirectly through the release of endogenous brain 5-HT.
Effect of amphetamine on the uptake, release and effectiveness of xylocholine in the guinea-pig vas deferens
Authors: DEAN H G , HUGHES I E 
Published: April 2011

Abstract
Amphetamine sulphate will both reverse and prevent the adrenergic neuron blocking action of xylocholine (TM10 bromide) on the response of the guinea-pig isolated vas deferens to transmural electrical stimulation. A concentration of amphetamine sulphate capable of reversing the effect of xylocholine does not produce a significant reduction in the tissue concentration of 14C-TM10 iodide in the vas deferens. Although amphetamine reduces the rate of uptake of xylocholine, it does not prevent uptake. Comparisons of tissue concentrations with the degree of blockade produced in the normal and the amphetamine-treated vas deferens suggest that if the actions of amphetamine are to be accounted for entirely by displacement of xylocholine or by changes in uptake of xylocholine, only a very small percentage of the total tissue content of xylocholine can be involved in the production of its effects.
Structure-activity relations for anticholinergic 2[1-aryl(or cyclohexyl)-1-hydroxy-1 -phenyl]methyl-1,3-dioxolans
Authors: BRIMBLECOMBE R W , INCH T D , WETHERELL JANET , WILLIAMS NANCY 
Published: April 2011

Abstract
The syntheses and configurational assignments of some 4-dimethyl aminomethyl-2[1-aryl (or cyclohexyl)-1 -hydroxy-1-phenyl]methyl-1,3-dioxolans are described. The anticholinergic potency of the 4-dimethylaminomethyl-2[l-cyclohexyl-l-hydroxy-l-phenyl]methyl-1,3-dioxolans, both in tertiary and quaternary form, depends principally on the configuration of the benzylic carbon atom, secondly on the C-2 configuration and thirdly, and to a much lesser extent, if at all, on the C-4 configuration. The dioxolans, which are derived formally from 4-dimethylaminomethyl-2-methyl-1,3-dioxolan methiodide (or its tertiary analogue) by replacement of the 2-methyl substituent by a 2[l-aryl (or cyclohexyl)-l-hydroxy-l-phenyl]methyl group and the glycollates which are derived formally from acetylcholine (or its tertiary analogue) by corresponding substitution of the acetoxymethyl group have closely similar anticholinergic potencies.
The ganglion blocking activity of diastereoisomeric dimethylaminobornyl acetates and their methiodides
Authors: COOPER G H , GREEN D M , RICKARD R L , THOMPSON PAMELA B 
Published: April 2011

Abstract
Some diastereoisomeric dimethylaminobornyl acetates and their methiodides have been prepared and tested for ganglion blocking activity. Included in these compounds was an enantiomeric pair and associated quaternary salts. These optical antipodes displayed virtually no difference between their actions at the ganglion. Differences between the activities of the least and most potent diastereoisomers was limited to a factor of about five. Assays were made upon the cat superior cervical ganglion and also the guinea-pig vas deferens preparation the successful quantitative use of which is described.
The reversal of experimental cardiac arrhythmias by indoramin (Wy 21901)
Authors: ALPS B J , HILL MADELINE , FIDLER K , JOHNSON E S , WILSON A B 
Published: April 2011

Abstract
Indoramin was approximately equipotent with (±)-propranolol but more potent than lignocaine in reversing adrenaline-induced multiple ventricular ectopic beats and ventricular tachycardia in halothane-anaesthetized cats. Indoramin was more potent than either propranolol or lignocaine in reversing ouabain-induced ventricular tachycardia or fibrillation to sinus rhythm. The local anaesthetic activity of indoramin was three times greater than that of procaine and lignocaine and twice that of (±)-propranol and quinidine when assessed by the guinea-pig wealtest. Experiments on the guinea-pig isolated ileum supporting a local anaesthetic action of indoramin showed that nicotine contractions were reduced by indoramin whereas acetylcholine responses were unaffected. Based on the evidence presented and that published elsewhere, it is considered likely that indoramin abolishes adrenaline-induced arrhythmias by a combination of membrane stabilization and blockade of myocardial α-adrenoceptors whereas ouabain arrhythmias may be reversed by membrane stabilization alone.
Methods for the preparation of lysophosphatidylcholine
Authors: MERRYFIELD DANUTA S , WREN J J 
Published: April 2011

Abstract
The surfactant and solubilizing properties of lysophosphatidylcholine (LPC) could have industrial uses if it became available in technical quantity and purity. The two most promising routes for obtaining it are isolation from cereal starches and mono-deacylation of egg phosphatidylcholine (PC). Baker's yeast autolysed by Letters's method yielded up to 0·3 % of LPC. The phospholipase A activity of pancreatin powder gave 80 % of the theoretical yield of LPC under optimum conditions; modifications designed to facilitate scale-up reduced the yield. Base-catalysed glycerolysis at 75° gave 23 % of the theoretical yield of LPC, and a reaction between PC and ethanolamine up to 45%. The crude product from ethanolamine after acetone precipitation gave an emulsifier containing LPC, PC and long-chain N-2-hydroxyethylamide.
The effect of suspensions on the bactericidal activity of m-cresol and benzalkonium chloride
Authors: BEAN H S , DEMPSEY G 
Published: April 2011

Abstract
The bactericidal activity of experimental aqueous suspensions of light kaolin with m-cresol as preservative agreed closely with the activity of aqueous m-cresol solutions not brought into contact with kaolin (i.e. aqueous reference solutions). In contrast the activity of light kaolin suspensions with benzalkonium chloride was lower than that of aqueous benzalkonium chloride solutions because of adsorption of preservative by the kaolin. Suspensions containing benzalkonium chloride possessed a greater activity than the corresponding supernatant solutions removed from contact with the kaolin, owing to some of the bactericide adsorbed on the kaolin becoming available to the bacteria. Suspensions of procaine penicillin with benzalkonium chloride gave similar results to those for kaolin.
Antagonism by propranolol of the inhibitory effect of phenoxybenzamine on noradrenaline uptake in vivo
Authors: CHANG C C , WANG WUAN-HSIANG 
Published: April 2011

Abstract
The reduction of noradrenaline stores and [3H]noradrenaline concentration in the heart of mice and rats induced by phenoxybenzamine-treatment, alone or in combination with cold-stress, was prevented by propranolol. Propranolol also antagonized a similar effect induced by phentolamine but not that induced by other noradrenaline uptake inhibitors, such as desipramine, cocaine, guanethidine and reserpine. Analysis of the time-course of antagonism by propranolol indicates that it was evident only when the β-adrenoceptor blocking agent remained in the body. The inhibitory effect of phenoxybenzamine on noradrenaline stores reappeared when propranolol was excreted. Propranolol alone did not change cardiac noradrenaline stores or [3H]noradrenaline. It is concluded that the restoration of reflexly increased adrenergic discharge to normal, because of unmasking of spare α-adrenoceptors resulting from β-adrenoceptor blockade by propranolol rather than competition for binding at the active site of phenoxybenzamine, is responsible for the observed antagonism.
The action of azapropazone, oxyphenbutazone and phenylbutazone on lysosomes
Authors: LEWIS D A , CAPSTICK R B , ANCILL R J 
Published: April 2011

Abstract
Azapropazone, oxyphenbutazone and phenylbutazone have a stabilizing action on isolated lysosomes over a wide concentration range but a lytic action at high concentrations. The lytic action of phenylbutazone was greater than the other drugs. Phenylbutazone at a high concentration was found to accelerate the breakdown of lysosomes in isolated stomach preparations in vitro. Phenylbutazone was found to have a greater ulcerogenic action than azapropazone in rats and rabbits. Tissues removed from rats and rabbits dosed with phenylbutazone showed evidence of lysosomal damage when examined histochemically for acid phosphatase. In contrast, tissues from control and azapropazone-treated rats showed no evidence of lysosomal damage. Sections of rat gut incubated with azapropazone and phenylbutazone in vitro showed similar results. The possibility is discussed that drugs in high concentration may damage lysosomes in the gastrointestinal tract. It is suggested that lysosomal damage may contribute to the ulcerogenic action of the drugs in vivo.
The excretion of hydroxyamylobarbitone in man after oral administration of amylobarbitone and hydroxyamylobarbitone
Authors: GROVE J , TOSELAND P A 
Published: April 2011

Abstract
The excretion of hydroxyamylobarbitone in man has been measured over six days after an oral dose of 200 mg of sodium amylobarbitone. The biological half-life of hydroxyamylobarbitone determined from “Sigma-minus” plots ranged between 16·8 and 22 h in seven subjects, in another subject the half-life was 34·4 h. The effects of increasing urine flow on the amount of hydroxyamylobarbitone excreted after ingestion of 200 mg of sodium amylobarbitone were assessed. A subject normally excreting 34% of the dose as hydroxyamylobarbitone excreted 45% of the dose as metabolite while taking chlorothiazide as a diuretic. With the same subject taking increased fluids to produce a greater urine flow 41% of the dose was excreted as hydroxyamylobarbitone. Hydroxyamylobarbitone is not bound to plasma proteins and when an aqueous solution of 50 mg of hydroxyamylobarbitone was taken by mouth, 57% of the dose was eliminated in the first 8 h and 91% in the first 24 h. The half-life for ingested hydroxyamylobarbitone was 5·7 h, showing that the rate of elimination of this metabolite is faster than its rate of formation when amylobarbitone is ingested.
The influence of methyl substitution on the N-demethylation and N-oxidation of normethadone in animal species
Authors: BECKETT A H , MITCHARD M , SHIHAB A A 
Published: April 2011

Abstract
N-Monodemethylation and N-oxidation were shown to be the major routes of metabolism of normethadone, (—)-methadone and (—)-isomethadone in vitro by hepatic microsomal preparations from rat, rabbit, guinea-pig, mouse and hamster. The rate of N-oxidation was decreased and the rate of N-demethylation was increased by the introduction of the methyl substituent into normethadone; the configuration of the methyl substituent influenced these processes. Km and Vmax values were determined for liver microsomal N-demethylation of normethadone, (—)-methadone and (—)-isomethadone by rat and guinea-pig and for the N-oxidation of normethadone by guinea-pig. The use of selective inhibitors showed that N-demethylation was not preceeded by N-oxidation in these compounds.
The effect of ethanol on phenobarbitone and pentobarbitone absorption into rat blood and brain
Authors: COLDWELL B B , TRENHOLM H L , THOMAS B H , CHARBONNEAU S 
Published: April 2011

Abstract
Male rats administered [14C]phenobarbitone (50 mg/kg) or [14C]-pentobarbitone (30 mg/kg) simultaneously with either 15% ethanol (3 g/kg) or saline intraperitoneally were killed 5, 10 or 20 min after injection. The radioactivity in the blood, whole brain and different brain areas was measured. Phenobarbitone was absorbed more slowly into the blood and brain than pentobarbitone. Ethanol-treated rats had significantly higher phenobarbitone concentrations than the saline-treated controls in the blood, whole brain, cerebrum and cerebellum up to 10 min after injection. Pentobarbitone concentrations were not significantly altered by ethanol. Barbiturate concentrations in the cerebral cortex were lower than in other regions of the brain. The brain: blood barbiturate ratios were not appreciably changed by ethanol. It is concluded that ethanol (15%) given intraperitoneally aided the transport of phenobarbitone across the peritoneum and hence increased the rate of its absorption into the blood and brain.
Infrared identification of sulphonamides using attenuated total reflection
Authors: EDWARDS D 
Published: April 2011

Abstract
The infrared spectra of ten sulphonamides have been determined by attenuated total reflection and compared with transmission spectra. No major differences were found in the positions and shapes of the main absorption peaks and it was possible to use ATR to identify sulphacetamide sodium in eye-drops and in eye ointments.
Administration of two or more related drugs to investigate the effect of molecular modification and formulation on drug absorption, metabolism and excretion
Authors: BECKETT A H , BROOKES L G 
Published: April 2011

Abstract
Two or more related drugs of the amphetamine class were simultaneously administered to man under acidic urine control, their urinary excretion being examined by gas-liquid chromatography. This was shown to be a suitable procedure for determining the effect of molecular modification and formulation on drug absorption, metabolism and excretion.