bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification in human urine of Δ9-tetrahydrocannabinol-11-oic acid glucuronide: a tetrahydrocannabinol metabolite
Authors: Williams P L , Moffat A C 
Published: April 2011

Abstract
A Δ9 -THC metabolite has been identified in human urine as an ester linked glucuronide of Δ9 -THC-11-oic acid. Its identity was established by a comparison of mass spectra from the metabolite extracted from human urine and synthetically prepared material. Δ9 -THC-11-oic acid glucuronide was found to be responsible for the major part of RIA crossreactivity in urine with the Guildhay cannabinoid antiserum used in this study.
Radioimmunoassay of diazepam in samples of forensic interest
Authors: Rutterford Mary G , Smith R N 
Published: April 2011

Abstract
The radioimmunoassay of diazepam in biological fluids is described. The method is particularly applicable to samples encountered in forensic toxicology that may be haemolysed, decomposed and of small volume. The antiserum and tritiated diazepam that are used are commercially available. Polyethylene glycol (mol. wt 6000) is used to separate the bound and free fractions, and the free fraction is counted by extracting the tritiated diazepam into a toluene-based scintillant. Blood samples are extracted with ethyl acetate before analysis but urine samples may be assayed directly. The assay is convenient, quick and virtually specific for diazepam. The results correlate well with those obtained by gas chromatography.
The influence of various counter ions on the interaction of chlorhexidine with the hydrophilic contact lens polymer, poly(2-hydroxyethyl methacrylate)
Authors: Plaut B S , Meakin B J , Davies D J G 
Published: April 2011

Abstract
The commercially available salts of chlorhexidine were found to interact with the hydrogel poly (2-hydroxyethyl methacrylate) to different extents, the affinity for the polymer decreasing in the order acetate, gluconate, chloride. The uptakes of the acetate and gluconate salts were almost entirely irreversible over the concentration range studied. The influence of some alternative counter ions, namely amino acids and dicarboxylic acid salts, was examined and found to generate a three-fold variation in the extent of the chlorhexidine interaction. Uptakes were greatest for counter ions that were either hydrophobic in character or bore a net negative charge. Only two compounds, glycine and monosodium oxalate, were successful in reducing the extent of sorption below that observed for chlorhexidine hydrochloride.
Effect of saturable binding on the pharmacokinetics of drugs: a simulation
Authors: Øie Svein , Guentert Theodor W , Tozer Thomas N 
Published: April 2011

Abstract
The time-courses of both total and unbound drug concentrations with time were simulated under conditions of saturable binding to either plasma proteins or tissues, or both, following a single intravenous dose. The curves were either linear, convex, or concave, depending upon the extent of distribution and the intrinsic ability of an eliminating organ to remove drug from the body. Saturable binding should therefore be considered whenever data showing nonlinear semilogarithmic decline are to be interpreted.
Investigations into the binding of phenprocoumon to albumin using fluorescence spectroscopy
Authors: Otagiri M , Fleitman J S , Perrin J H 
Published: April 2011

Abstract
The fluorescence of phenprocoumon is enhanced following interaction with bovine and human serum albumin, allowing the binding parameters for two binding sites to be estimated by a modified Bjerrum method and the Scatchard method. The fluorescence is increased as the pH is raised to 9·0 and also on addition of the drugs ibuprofen and fenoprofen. Chloride ions, phenylbutazone and acenocoumarin seem to displace phenprocoumon from its primary binding site on human serum albumin. Investigations with the enantiomers of phenprocoumon show that the binding sites have some stereospecificity.
On the metabolism of clofibride, a hypolipaemic drug
Authors: Loiseau Gérard P , Millischer René J , Lohier Pierre V , Mardiguian Jean S , Gilede Anne-Marie Pieux , Ginocchio A V 
Published: April 2011

Abstract
The absorption and metabolism of clofibride, a new hypolipaemic drug of p-chlorophenoxyisobutyric type, were investigated in the CD rat, the beagle and the olive baboon monkey. Clofibride is rapidly and massively resorbed and hydrolysed into 4-chlorophenoxyisobutyric acid (CPIB) and 4-hydroxy-N-dimethylbutyramide (HMB). CPIB, in free and glucuroconjugated form, and its metabolite, 4-chlorophenol, in the form of the glucuronate ether, are found in the serum of the rat. HMB is rapidly metabolized. The half-life of CPIB, the main active metabolite, in the serum is about 12 h in the rat, 43 ± 9 h in the dog and 6 ± 1 h in the baboon. In the rat, peak hypocholesterolaemic activity occurs late—24 h after administration of the drug and 20 h after peak concentration of CPIB in the blood. The half-life of 4-chlorophenol glucuronate ether in the serum is about 4 h whereas that of HMB is about 3 h. In the rat, the elimination of clofibride takes place mainly via the urine since 70% of the dose administered is found in the form of free or conjugated CPIB, 10% in the form of HMB or one of its metabolites, in 48 h samples of urine. Over the same period, faecal elimination accounts for no more than 2% of the dose ingested. In addition, in this species, the CPIB, 30% of which is secreted via the biliary route without being eliminated in the faeces, undergoes an enterohepatic circulation.
The catecholamine mechanisms of prostaglandin E1-induced hypothermia in rats
Authors: Lin M T , Chandra A , Sun R , Kau C L 
Published: April 2011

Abstract
Intraperitoneal administration of prostaglandin E1 (PGE1) produced a hypothermia in rats at room temperature (22°C). The hypothermia in response to PGE1 was due to cutaneous vasodilatation and decreased metabolic heat production. Depletion of brain 5-hydroxytryptamine (with 5,6-dihydroxytryptamine and p-chlorophenylalanine) did not alter the PGE1-induced hypothermia. However, depletion of brain catecholamines (with 6-hydroxydopamine) and blockade of central catecholaminergic receptors (with phentolamine and propranolol) both greatly reduced the PGE1-induced hypothermia. The data indicate that PGE1 lowers body temperature in rats by acting on the central catecholaminergic systems.
Self-association of analgesics in aqueous solution: micellar properties of dextropropoxyphene hydrochloride and methadone hydrochloride
Authors: Attwood D , Tolley J A 
Published: April 2011

Abstract
The solution properties of several analgesics including dextropropoxyphene hydrochloride, methadone hydrochloride, dextromoramide acid tartrate and dipipanone hydrochloride have been examined using light scattering, conductivity, vapour pressure osmometry and surface tension techniques. A micellar pattern of association was established for dextropropoxyphene hydrochloride and methadone hydrochloride and critical micelle concentrations and aggregation numbers are reported. The hydrophobic contribution to the free energy of micellization of dextropropoxyphene was determined from measurements of the critical micelle concentration in the presence of added electrolyte.
Decrease in aspirin-induced gastric mucosal damage in rats by oral administration of the cytotoxic drugs melphalan and methotrexate
Authors: Berstock D A , Frank G J , Stamford I F , Bennett A 
Published: April 2011

Abstract
Gastric mucosal damage by aspirin and chemotherapeutic drugs was studied in Wistar rats. Aspirin 60 mg given by stomach tube caused substantial gastric mucosal damage as judged by visual examination of the stomachs removed four hours later. Melphalan and methotrexate given daily for four days had no significant macroscopic effect on the gastric mucosa, but reduced the damage caused by aspirin. This protective effect may involve a stimulation of prostaglandin synthesis by the stomach, increased mucus secretion, and/or inhibition of acid secretion.
The effect of dosage on the bioavailability of chlorothiazide administered in solution
Authors: Corrigan Owen I , O'Driscoll Katherine M 
Published: April 2011

Abstract
Chlorothiazide in solution was administered at four dose levels to three healthy male volunteers under controlled conditions. Excretion data indicated that the drug was poorly absorbed from the gastrointestinal tract. The 24 h recovery of the drug from urine fell from 33 to 6% as the dose was increased from 0·21 to 1·75 g per 70 kg of body weight. The cumulative amount of sodium excreted could be correlated with the cumulative amount of drug excreted, rather than with the dose administered. The electrolyte excretion response intensity could also be correlated with the amount of drug excreted. There was a poor linear relationship between response intensity and drug excretion rate. After higher doses the data suggested that the response was in the non-linear section of the dose response curve.
Vasoactive intestinal polypeptide (VlP)-sensitive adenylate cyclase in rat brain: regional distribution and localization on hypothalamic neurons
Authors: Kerwin R W , Pay Sarah , Bhoola K D , Pycock C J 
Published: April 2011

Abstract
The regional distribution of the vasoactive intestinal polypeptide (VlP)-sensitive stimulation of adenylate cyclase activity was studied in homogenates of rat brain. The order of sensitivity of this peptide on enzyme activity was: olfactory bulb &gt; hippocampus &gt; thalamus &gt; occipital cortex ⋍ frontal cortex ⋍ midbrain ⋍ hypothalamus &gt; striatum &gt; cerebellum ⋍ brain stem &gt; spinal cord. With neurotoxin-induced lesions the possible location of VIP-sensitive adenylate cyclase within the anterior hypothalamus was investigated. Intrahypothalamic 6-hydroxydopamine blocked the stimulatory effect of VIP on hypothalmic adenylate cyclase, but neither kainic acid nor 5,7-dihydroxytryptamine lesions had any effect. Similarly, there was a 71 % reduction in the sensitivity of VIP-sensitive adenylate cyclase activity in animals whose hypothalamic noradrenergic innervation had been interrupted by transection of the ascending dorsal and ventral bundles. Biochemical analyses of the lesions suggested that loss of VIP action on adenylate cyclase was associated with loss of hypothalamic noradrenaline-containing neurons. These results may give insight into those regions of rat brain where VIP may have a neurotransmitter role, and point to a possible noradrenergic localization of the VIP-sensitive adenylate cyclase within the hypothalamus.
On the ability of N-chloroethyl aporphine derivatives to cause irreversible inhibition of dopamine receptor mechanisms
Authors: Costall B , Fortune D H , Granchelli F E , Law S-J , Naylor R J , Neumeyer J L , Nohria V 
Published: April 2011

Abstract
The potential dopamine inhibitory properties of (-)N-(2-chloroethyl)-norapomorphine [(-)NCA], (-)N-(hydroxyethyl)norapomorphine [(-)NHA], (-)N-(2-chloroethyl)-norapocodeine[(-)NCC] and 6-[2-bis-(2-chIoroethyl)-amino]acetyl-11-acetoxy-2-hydroxy-10-methoxynoraporphine (I) were assessed in behavioural (ability to antagonize apomorphine climbing, stereotypy and circling after unilateral electrolesions of the striatum in the mouse, ability to initiate circling/asymmetry alone or after challenge with apomorphine when injected unilaterally into the striatum of rat) and biochemical (ability to inhibit the binding of [3H] (-)N-n-propylnorapomorphine, 3H-NPA, to rat striatal homogenates) tests. (-) NCA, 10–20 mg kg−1 s.c., antagonized apomorphine climbing for a period of 5 days, the response recovering to control values by the 7th day. 10 mg kg−1 s.c. (-)NHA, (-)NCC or I failed to modify apomorphine climbing. Similarly, 2–4 mg kg−1 s.c. (-)NCA caused a long-lasting inhibition of apomorphine circling in the mouse (up to 5 days) whilst (-)NHA, (-)NCC and I were inactive. (-)NCA (10–40 μg) (but not (-)NHA, (-)NCC or I) also caused ipsilateral circling/asymmetry when injected unilaterally into the striatum of rat: this effect was enhanced by apomorphine. However, all agents, including (-)NCA, failed to consistently modify apomorphine stereotypy in the mouse. Non-labelled (-)NPA, (-)NCA and (-)NHA were shown to inhibit the ‘specific’ binding of 3H-NPA to rat striatal homogenates; (-)NCC and I were ineffective. A single washing removed the (-)NHA inhibition whilst repeated washing caused only a modest reversal of the inhibition afforded by (-)NCA. It is concluded that N-chloroethylation in the aporphine series can abolish dopamine agonist action and confer a long-lasting dopamine antagonist potential.
Aerodynamic size distribution, hygroscopicity and deposition estimation of beclomethasone dipropionate aerosol
Authors: Hiller F C , Mazumder M K , Wilson J D , Bone R C 
Published: April 2011

Abstract
Aerodynamic size distribution and aerodynamic mass per dose of beclomethasone dipropionate aerosol were measured at 24 and 95% relative humidity. At high humidity, the count median aerodynamic diameter was unchanged, mass median aerodynamic diameter increased from 2·01 μm to 2·68 μm, particle number/dose from 41·3 times 106 to 78·3 times 106, and aerodynamic mass per dose from 23·7 to 60·0μ g. The quantity of active ingredient estimated to be in the 23·7μg aerodynamic mass at low humidity was 19·7 μg. From data previously available describing average deposition fraction as a function of aerodynamic diameter, 6·7 μg or 13% of the total dose of 50μg produced by the metered dose canister would be expected to deposit in the lower respiratory tract.
Light scattering studies of the solubilization of some esters of p-aminobenzoic acid by lysophosphatidylcholine
Authors: Hunt M J , Saunders L 
Published: April 2011

Abstract
Light scattering equipment has been constructed using a vertically polarized helium-neon laser and a phase-sensitive detection system. The apparatus has been used to determine the micellar weight of lysophosphatidylcholine (LPC), giving values of 1·33 times 105 in water and 1·47 times 106 in 0·05 M sodium chloride; the sols showed some degree of polydispersity. The light scattering apparatus has also been used to study the solubilization by LPC of three n-alkyl esters of paraminobenzoic acid. These compounds caused a considerable increase in the scattered light, particularly at higher LPC concentrations.
Influence of phenobarbitone pretreatment on disposition of amidopyrine and its metabolites in rat
Authors: Lockwood G F , Houston J B 
Published: April 2011

Abstract
Plasma concentration-time profiles for amidopyrine and its primary desmethyl metabolite have been determined in control rats and in rats pretreated with phenobarbitone. The kinetics of both compounds indicate enhanced clearance following pretreatment. Metabolite excretion in urine, bile and breath support the plasma data. It would appear that phenobarbitone pretreatment results in quantitative but not qualitative changes in the metabolism of amidopyrine in rat.
Evidence for thermoregulatory dopaminergic receptors located in the preopticus medialis nucleus of the rat hypothalamus
Authors: Colboc O , Costentin J 
Published: April 2011

Abstract
Systemic administration of apomorphine induces hypothermia in anaesthetized rats as well as in conscious rats exposed to an ambient temperature of 22 °C. The central nature of this effect is confirmed by the antagonism exerted by haloperidol and the lack of antagonism with domperidone. Dopamine receptors involved in the hypothermic effect of apomorphine seem to be located in the preopticus medialis nucleus (p.o.m.n.) of the hypothalamus since: (i) injections of apomorphine (5 ng), dopamine (100 ng) or (+)-amphetamine (50 ng) into this nucleus induce hypothermia, (ii) haloperidol injected into the p.o.m.n. antagonizes the hypothermic effect of a systemic administration of apomorphine, (iii) heat lesions of the p.o.m.n. strongly reduce the hypothermic effect of a systemic injection of apomorphine.
Influence of calcium on noradrenaline release evoked by 5-hydroxytryptamine, tyramine and potassium from goat pial arteries
Authors: Marin J , Sanchez C F 
Published: April 2011

Abstract
The release of tritium (3 H) evoked by tyramine, potassium (K+) and 5-hydroxytryptamine (5-HT) from goat pial arteries preloaded with [3 H]noradrenaline (3 H-NA) was studied. In normal Krebs-bicarbonate solution (KBS) all these agents caused a transient increase in radioactivity release over the basal spontaneous outflow. The pattern of release evoked by 5-HT was similar to that induced by tyramine with a slow onset and decline, but different from that induced by K+ which produced a rapid peak of 3 H release followed by a quick fall. The removal of Ca2+ from the medium did not modify the efflux of radioactivity caused by tyramine, but the 3 H efflux produced by K+ was markedly reduced. Nevertheless, in this Ca2+ -free medium the 3 H release evoked by 5-HT was partially, but significantly, decreased. These results indicate that K+ evokes NA release by a Ca2+ -dependent process, probably of an exocytotic nature, while tyramine mediates NA release by means of a Ca2+ -independent mechanism. However, 5-HT possesses a Ca2+ -dependent and a tyramine-like component.
Dissolution rates of sulfamethoxazole utilizing sugar glass dispersions
Authors: Ghanem A , Meshali M , Ibraheem Y 
Published: April 2011

Abstract
Solid glass dispersions of sulfamethoxazole have been prepared by fusion using different classes of sugars, A marked increase in the dissolution rate of sulfamethoxazole in the solid dispersions was observed compared with that of the drug alone. During the fusion process, interaction took place between sulfamethoxazole and those sugars with carbonyl groups. The bacteriological activity of sulfamethoxazole was not changed by the interaction compared with dispersions in which the interaction did not occur.
Sustained-release dosage forms of microencapsulated isoniazid
Authors: Jalŝenjak I , Nixon J R , Senjkovic R , Ŝtivic I 
Published: April 2011

Abstract
The preparation and release characteristics of microcapsules of isoniazid have been studied. The differing techniques of microencapsulation are assessed and the dissolution of drug from suspended and tableted microcapsules prepared using the chosen technique has been monitored for in vitro release.
The effect of lipid-depletion on the kinetic properties of rat liver monoamine oxidase-B
Authors: Fowler C J , Oreland L 
Published: April 2011

Abstract
The extraction of lipids from rat liver mitochondrial membranes by 2-butanone treatment inhibited the activity of membrane-bound monoamine oxidase -A but not -B. For the -B form, the apparent Michaelis constants of the enzyme towards oxygen and the maximum molecular turnover numbers obtained when β-phenethylamine and benzylamine were used as substrates were not significantly changed by the lipid-depletion procedure, but the values of the Michaelis constant towards benzylamine was significantly increased after lipid- depletion. The differential sensitivity of β-phenethylamine and benzylamine oxidation to inhibition by Tris-HCI was not changed after lípid-depletion. The results are consistent with the hypothesis that the mitochondrial membrane lipids, while essential for the actìvìty of the -A form of the enzyme in rat liver, play a more subtle modulatory role in the activity of the -B form.
The effects of the optical isomers of propranolol on functional refractory period in rat isolated myocardium
Authors: Tomlinson D R , Haworth S C , Harmsworth N J , Ross A M 
Published: April 2011

Abstract
The two optical isomers of propranolol caused a concentration-dependent increase in functional refractory period of the rat isolated left atrium. In this property the isomers were equipotent. Noradrenaline (1 times 10−7 M) decreased the functional refractory period. This effect was completely reversed by (-)-propranolol. The (+)-isomer was much less potent than (-)-propranolol in antagonizing the effects of noradrenaline on functional refractory period.
Effect of prenatal Phenytoin administration on brain tryptophan metabolism of rat offspring during the preweaning period
Authors: Elmazar M M A , Sullivan F M 
Published: April 2011

Abstract
Serum 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) concentrations in control rat offspring increased progressively during the preweaning period reaching adult values by day 21. It has been shown that prenatal phenytoin administration (100 mg kg−1 orally, days 7–19 of pregnancy) increased serum tryptophan and brain tryptophan, 5-HT and 5-HIAA of rat offspring at 3 days of age but not at 4, 15 or 21 days of age. The effect of prenatal phenytoin administration on the offspring at 3 days of age was not observed when these pups were cross-fostered to control mothers at 2 days of age suggesting that the alteration in brain tryptophan metabolism during the development of tryptaminergic neurons in rat offspring, as a result of prenatal phenytoin administration is mediated through changes in lactation or nursing ability of the mothers. It is important that such non-specific factors are controlled when studying the effect of prenatally administered drugs on neonatal brain transmitter concentrations.
Carrageenan-induced activation of human platelets is independent of phospholipase A2 and of formation of thromboxanes
Authors: Vargaftig B B , Fouque F , Chignard M , Dumarey C 
Published: April 2011

Abstract
Aggregationof washed rabbit platelets by thrombin and by carrageenan is accompanied by the activation of phospholipase A2 and by the synthesis of thromboxanes. Accordingly, aggregation, the accompanying release reaction and the activation of phospholipase are blocked by p-bromophenacyl bromide and by CB 874 (2,3-dibromo (4′-cyclohexyl-3′-chloro)-phenyl-4- oxo-butyric acid), two recognized inhibitors of the enzyme. Since these two reagents also inhibit aggregation and the release reaction induced by thrombin and by carrageenan on washed human platelets, it might have been anticipated that the mechanisms of aggregation of the platelets from the two species are similar. Nevertheless, no thromboxanes A2 or B2, nor activation of phospholipase A2 could be demonstrated with the use of carrageenan on human platelets, under conditions where thrombin was effective. It is concluded that carrageenan activates the human platelets by phospholipase A2- and thromboxane A2-independent mechanisms, and that the inhibitors of phospholipase A2 may block platelet functions by mechanisms other than inhibition of the expected enzyme.
Self-association of analgesics in aqueous solution: association models for codeine, oxycodone, ethylmorphine and pethidine
Authors: Attwood D , Tolley J A 
Published: April 2011

Abstract
Light scattering, vapour pressure osmometry, conductivity and surface tension techniques have been used to examine aqueous solutions of several narcotic analgesics for evidence of association. Contrary to a previous report, no significant association could be detected in solutions of morphine sulphate and codeine phosphate. Other drugs which showed no evidence of aggregation in water included morphine hydrochloride, ethylmorphine hydrochloride, oxycodone hydrochloride and dihydrocodeine tartrate. Self-association of ethylmorphine hydrochloride, oxycodone hydrochloride and codeine phosphate was observed in the presence of 0·5 mol dm−3 electrolyte, the pattern of association conforming to that of a stepwise association process with all association constants of equal value. The association of pethidine hydrochloride in 0·5 mol dm−3 sodium chloride could be represented by an association scheme in which association constants KN increased sequentially with aggregation number N according to the relation KN = K(N — 1)/N.