bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of solution viscosity on the dissolution rate of soluble salts, and the measurement of an “effective” viscosity
Authors: Florence A T , Elworthy P H , Rahman A 
Published: April 2011

Abstract
The rate of solution of KCl and NaCl from compressed discs has been determined under controlled conditions, in water at 25° and in solutions of varying concentrations of polyvinylpyrrolidone (molecular weight 360 000), polyoxyethylene glycol 6000 and cetomacrogol 1000. Dissolution rate constants decrease with increasing bulk solution viscosity, as expected, but no one equation relating rate constant and bulk viscosity fits the results for the systems studied. Calculation of an effective viscosity from the diffusion coefficients of the salts in water and the diffusion coefficients of the salt in the polymer solutions enables an empirical correlation of the results to be made. The relation of the effective viscosity to the microscopic viscosity is discussed in an Appendix.
Dextromethorphan-monoamine oxidase inhibitor interaction in rabbits
Authors: Sinclair John G 
Published: April 2011

Abstract
Severe toxic reactions may occur clinically when imipramine, pethidine or dextromethorphan is administered to a patient being treated with a monoamine oxidase inhibitor (MAOI). Previous reports indicate that imipramine or pethidine produces symptoms characterized by motor restlessness, tremor, extreme hyperpyrexia and death when administered to phenelzine-pretreated rabbits. The present study shows that dextromethorphan (5 mg kg−1) produces identical symptoms in rabbits pretreated with phenelzine sulphate (30 mg kg−1) or nialamide HCl (50 mg kg−1) 42 and 18 h before temperature recording. The dextromethorphan-MAOI interaction appears to be due to a 5-hydroxytryptamine potentiation. In the unanaesthetized cat nictitating membrane preparation, dextromethorphan (5 mg kg−1) markedly enhanced the response of noradrenaline and 5-HT but antagonized the effects of tyramine. This suggests that dextromethorphan blocks the uptake of these amines in the adrenergic nerve endings.
The 5-hydroxytryptamine content of rabbit hearts and its release during in vitro perfusion
Authors: Fozard J R , Mwaluko G M P 
Published: April 2011

Abstract
Rabbit hearts were perfused in vitro at constant pressure by the Langendorff technique. After 30 min perfusion, hearts from untreated animals contained significantly more 5-HT than those from animals pretreated with heparin. The cardiac 5-HT content of the non-heparinized group decreased during a further 55 min perfusion and the amount lost from the hearts was equal to that recovered from the perfusion fluid. In contrast, the 5-HT content of hearts from heparinized animals did not change significantly during this period, and no 5-HT could be detected in the perfusates. Investigation of the distribution of 5-HT within the hearts from heparinized animals disclosed a significantly greater concentration of 5-HT in the right atrium than in the rest of the heart. It is concluded that the small, perfusion-resistant store of 5-HT within hearts from heparinized rabbits represents the true endogenous 5-HT content in this species, but that much higher values may be obtained unless care is taken to exclude a contribution from blood platelets.
Evidence for catecholamine involvement in the suppression of locomotor activity due to hypoxia
Authors: Brown Roger , Engel Jörgen 
Published: April 2011

Abstract
Locomotor activity of mice under 12 or 21% oxygen in nitrogen was measured. Under 12% oxygen there was a decrease in locomotor activity which was not reversed by administration of amphetamine; however, administration of a sub-threshold dose of l-dopa in combination with a peripheral decarboxylase inhibitor before the amphetamine restored the locomotor stimulant action of the drug under hypoxia. In contrast to amphetamine, the increase in locomotor activity after the administration of a combination of noradrenaline and dopamine receptor stimulating agents, Clonidine plus apomorphine respectively, was not inhibited by hypoxic conditions. Data suggest an involvement of central catecholamine neurotransmission in the disruption of locomotor activity due to hypoxia.
Conopharyngine pseudoindoxyl, a new alkaloid from Tabernamontana pachysiphon Stapf, var cumminsii (Stapf.) H. Huber
Authors: Crooks P A , Robinson B 
Published: April 2011

Abstract
A chlorform extract of the residue, remaining after extraction of the bases obtained from the leaves of T. pachysiphon var cumminsii* with ether, has been shown to contain the alkaloids conopharyngine, 20-hydroxyconopharyngine and conopharyngine pseudo-indoxyl, and two alkaloids of as yet unknown structure.
The effect of particulate dispersing agents on the antifoaming properties of dimethicone 1000 in antiflatulent products
Authors: Carless J E , Stenlake J B , Williams W D 
Published: April 2011

Abstract
The effect of finely divided silica on the antifoaming properties of polydimethylsiloxanes (dimethicone 1000) when formulated in a typical antiflatulent tablet has been examined. A dynamic froth test has been used to show that removal of extractable dimethicone by ether extraction of the tablet powder markedly reduces the antifoaming properties of the powder, despite retention of a small percentage of the polydimethylsiloxane dispersed on the surface of the silica and aluminium hydroxide gel content of the tablet. A series of static froth tests similarly demonstrate that tablet formulations from which silica is omitted also possess significant antifoaming properties.
The effect of free silica on the mucosal protective and antiflatulent properties of polydimethylsiloxane
Authors: Birtley R D N , Burton J S , Kellett D N , Oswald B J , Pennington J C 
Published: April 2011

Abstract
The mucosal protective and antiflatulent properties of polydimethylsiloxane (PMS) alone, or containing free silica have been examined in rats. Both PMS and PMS + 6% silica significantly protected rat gastric mucosa from the irritant effects of aspirin but there was no significant difference between the protective effect of each agent. The antiflatulent property of PMS, as determined by X-ray measurements of foam production in the rat stomach, was significantly enhanced by the addition of free silica.
The binding of conformationally restricted antihistamines to histamine receptors
Authors: Ison R R , Franks Fiona M , Soh K S 
Published: April 2011

Abstract
Some 1,1-diary 1–3-aminoprop-1-enes and 1,2-diaryl-4-amino-but-1-and −2-enes, including isomers of triprolidine and pyrrobutamine, have been prepared, their geometrical configurations established by pmr spectroscopy, and their affinities for histamine receptors measured on the guinea-pig ileum. These isomers differed considerably in their affinities and a particularly large difference was observed with the isomers of triprolidine (1170:1). This is because the binding of 3-aminoprop-1-enes is enhanced when α-pyridyl and aminomethyl groups are trans to one another or when p-tolyl and aminomethyl groups are cis, whereas activity is reduced when these groups are in opposite configurations. There is also a considerable difference between the geometrical isomers of pyrrobutamine (ca 200:1) but the most active compounds all have the same configuration whether 3-aminoprop-1-enes or 4-aminobut-2-enes. For high activity it appears necessary to have a trans Ar.C: CH.CH2.NC4H8 arrangement with the aromatic nucleus (α-pyridyl or phenyl) coplanar with the double bond, together with an aromatic function such as p-tolyl, benzyl or p-chlorobenzyl in a position cis to the aminomethyl group. All these compounds have restricted conformations so that the series serves as a useful model for the stereochemical requirements of the antihistamine receptor.
The pharmacology of azidomorphine and azidocodeine
Authors: Knoll J , Furst Susanna , Kelemen K 
Published: April 2011

Abstract
From a series of newly synthesized morphine derivatives 6-deoxy-6-azidodihydroisomorphine (azidomorphine) and 6-deoxy-6-azidodihydroisocodeine (azidocodeine) were selected for detailed pharmacological study. In the hot plate test in rats, azidomorphine proved to be about 300 times and azidocodeine about 13 times more potent than morphine. Azidomorphine given over ten weeks was significantly less toxic in the rat than morphine or fentanyl. A total dose 40 times that of the analgesic ED50 dose of morphine (200 mg kg−1) produced the highest grade physical dependence in mice as measured by naloxone-precipitated jumping. However, even a total dose of 2800 times the analgesic ED50 dose of azidomorphine (70 mg kg−1) was less effective in producing physical dependence. Treatment on every second day with increasing doses of morphine led to the development of high grade tolerance and chronic physical dependence in rats and monkeys (Rhesus macacus). Severe abstinence syndrome was precipitated after the administration of nalorphine in rats pretreated for 24 days with rapidly increasing doses of morphine and grave symptoms of abstinence were elicited in pretreated monkeys on withdrawal of morphine on the 55th, 175th and 300th days of treatment. In parallel experiments neither the development of tolerance nor that of physical dependence was demonstrable in rats and monkeys pretreated with increasing equi-analgesic doses of azidomorphine.
Antibronchoconstrictor activity of two new phosphodiesterase inhibitors, a triazolopyrazine (ICI 58 301) and a triazolopyrimidine (ICI 63 197)
Authors: Davies G E 
Published: April 2011

Abstract
A triazolopyrazine (ICI 58 301) and a triazolopyrimidine (ICI 63 197), both potent inhibitors of 3′5′-cyclic adenosine monophosphate phosphodiesterase, protected conscious guinea-pigs against an otherwise lethal bronchospasm caused by inhalation of histamine. Both compounds were active when given by mouth and the activity was both rapid in onset and persistent. Bronchospasm caused by histamine or acetylcholine in guinea-pig isolated lungs was reduced when the lungs were perfused with dilute solutions of the compounds and the bronchodilator activity of catecholamines was potentiated. In anaesthetized animals the compounds were relatively more active against severe bronchospasm than against milder stimuli. The antibronchoconstrictor effects on conscious guinea-pigs were blocked by propranolol but not by practolol even in much larger doses. Propranolol did not, however, block the effect on the isolated lung. It appears possible that the antibronchoconstrictor activity is a manifestation of the inhibition of phosphodiesterase.
Further observations on the experimental antidysrhythmic activity of indoramin hydrochloride
Authors: Rashid S , Alps B J 
Published: April 2011

Abstract
Indoramin showed potent activity in reversing severe myocardial conduction disorders and ventricular fibrillation induced by hypothermia, and protected against the precipitation of electrically-induced ventricular fibrillation at low doses in pentobarbitone-anaesthetized cats. It would appear that the α-adrenoceptor blocking and local anaesthetic membrane stabilizing properties of indoramin are responsible for the mechanisms by which these dysrhythmias are reversed as they are with those induced by ouabain and adrenaline, previously described.
A quantitative approach to the in vitro availability of drugs from some non-ionic surfactant solutions
Authors: Collett J H , Withington R 
Published: April 2011

Abstract
Equations that can be used in calculating the theoretical dialysis rates of drugs from surfactant solutions have been derived. Theoretical dialysis rates for the dialysis of salicylic acid from polysorbate solutions at a range of pH levels are compared with those determined experimentally. At low pH levels there is good agreement between theoretical and experimental values. With increasing pH at each surfactant concentration the values diverge. A possible reason for this divergence is considered.
The packing properties of moist bulk solids
Authors: Eaves T , Jones T M 
Published: April 2011

Abstract
The specific volumes of three bulk solids at moisture contents up to 50% w/w (dry basis) under various consolidating stresses have been shown to be dependent on the nature of the bulk solid. The values obtained can be related to the intraparticulate porosity and inherent cohesiveness of the dry materials. The influence of moisture on the packing properties and tensile strength of the three bulk solids is discussed in terms of the granulation process.
Decreased conversion of tyrosine to catecholamines in the brain of rats treated with p-chlorophenylalanine
Authors: Tagliamonte A , Tagliamonte P , Corsini G U , Mereu G P , Gessa G L 
Published: April 2011

Abstract
Repeated treatment with p-chlorophenylalanine (100 mg kg−1) daily for 5 days impairs the transport of amino-acids from plasma into the brain and decreases the rate of conversion of [3H]tyrosine to [3H] catecholamines in the rat brain. The possible mechanisms involved are discussed.
Comparative convulsant activity of various penicillins after intracerebral injection in mice
Authors: Gerald Michael C , Massey Joanne , Spadaro Daniel C 
Published: April 2011

Abstract
The convulsant effects of penicillin derivatives (penicillin G, Phenoxymethylpenicillin, penicillin O, ampicillin, methicillin) and cephaloridine have been evaluated after being given intracerebrally to mice. Penicillin G was most neurotoxic; ampicillin and Phenoxymethylpenicillin were one-fifth as toxic. Incubation with penicillinase markedly reduced or eliminated the convulsant effects of penicillin G, Phenoxymethylpenicillin and ampicillin; this enzyme incubation did not alter the severity of seizures elicited by methicillin and cephaloridine. Diphenylhydantoin and phenobarbitone did not reduce penicillin G-induced seizures. A non-convulsant dose of leptazol potentiated the convulsions produced by the penicillins and cephaloridine. Injection volume, pH and the concentration of sodium and potassium did not produce behavioural changes within the ranges studied.
Continuous shear, viscoelastic and spreading properties of a new topical vehicle, FAPG base
Authors: Barry B W 
Published: April 2011

Abstract
The rheology of a new topical vehicle FAPG base was investigated over the temperature ranges of 25–37°. Continuous shear rheograms obtained with a Ferranti-Shirley cone and plate viscometer were hysteresis loops with spur points; loop areas, yield values and apparent viscosities decreased with increase in temperature and an activation energy for viscous flow of 10.4 kcal mol−1 (43.5 kJ mol−1) was derived. In creep (concentric cylinder geometry) the base was viscoelastic with a low limit of linearity with respect to strain. Creep compliance curves showed an initial elastic response, a region of retarded elasticity and a viscous region; compliances increased and viscosities decreased with temperature rise. Patient acceptance of skin spreadability of the base was assessed using a master curve concept; the spreading properties were close to the preferred values for maximum patient acceptance. It is concluded that FAPG base deserves further study as a vehicle for dermatological use.
Mass spectrometry in the analysis of steroid drugs and their metabolites: electron-impact-induced fragmentation of ring D
Authors: Middleditch B S , Vouros Paul , Brooks C J W 
Published: April 2011

Abstract
Certain steroid drugs, their metabolites, and related model compounds which possess a 17-hydroxy group can be converted to trimethylsilyl ethers which give characteristic ions of type [128 + R]+in their mass spectra, where R is the mass of the other 17-substituent. Extensive deuterium labelling studies are carried out to verify the modes of formation of these and related ions which are of diagnostic value in analytical work.
The estimation of acetylsalicylic acid and salicylate in biological fluids by gas-liquid chromatography
Authors: Thomas Barry H , Solomonraj G , Coldwell Blake B 
Published: April 2011

Abstract
A gas-liquid chromatographic method is described for the simultaneous separation and determination of acetylsalicylic acid (ASA) and salicylic acid (SA) in biological fluids. The salicylates are completely extracted from deproteinized plasma or urine at pH 2 with ether containing p-toluic acid as the internal standard. The silylated derivatives are formed using bis(trimethylsilyl) trifluoroacetamide and separated at 150° on preconditioned 100–120 mesh Gas-Chrom Q coated with 5% OV17 packed into a 6 ft, 1/4 inch o.d. glass column in a gas chromatograph with a flame ionization detector and integrator. Detector response is linear over the range from 0–2 mg ml−1 for SA and from 0–100 μg ml−1 for ASA. The time required for the analysis of SA alone or with ASA is about 80 min, the analysis of ASA alone requires about 20 min. The precision of the method is 1 % or better for drug concentrations above 10 μg ml−1. The limits of detectability for SA and ASA are 1 and 2 μg ml, respectively.
A circular dichroic investigation of the binding of fenoprofen, 2(3-phenoxyphenyl)-propionic acid, to human serum albumin
Authors: Perrin J H 
Published: April 2011

Abstract
The extrinsic Cotton effects found on the binding of fenoprofen and some of its analogues to human serum albumin have been investigated. The fenoprofen appears to bind hydrophobically to the albumin via the phenyl rings and after dipole interactions of the carbonyl group and the ether oxygen. This binding is non-stereospecific.
Further studies on the adrenergic neuron blocking activity of some β-adrenoceptor antagonists and guanethidine
Authors: Mylecharane E J , Raper C 
Published: April 2011

Abstract
The effects of low (0.2) and high (20 μg ml−1) concentrations of (±)- and (+)-propranolol, (±)-, (+)- and (-)-sotalol and guanethidine were tested for their ability to reduce responses to sympathetic stimulation in the isolated vas deferens preparation from the guinea-pig. At 0.2 μf ml−1 all drugs produced a slowly developing reduction in the responses to sympathetic stimulation while responses to noradrenaline were largely unchanged. The blockade, which was similar in extent in all six compounds, was reversed by (+)-amphetamine but not by washing. With high concentrations of and (±)-propranolol and guanethidine, the block was rapid in onset and rate and responses to noradrenaline were potentiated. The block was reversed by washing and unaffected by (+)-***amphetamine. Sotalol and its isomers, which possess little non-specific depressant activity, had qualitatively similar actions at 0.2 and 20 μg ml−1. At the latter concentration responses to noradrenaline were potentiated. The results suggest that low concentrations of the β-adrenoceptor antagonists produce a blockade which is typical of guanethidine-like drugs. At high concentrations non-specific depressant (local anaesthetic) actions of propranolol and its isomers are largely responsible for the blockade. A similar mechanism may also operate when high concentrations of guanethidine are used.
The pharmacokinetics of phentermine and chlorphentermine in chronically treated rats
Authors: Lüllmann Heinz , Rossen Elisabeth , Seiler Klaus-Ulrich 
Published: April 2011

Abstract
Young rats were treated with [3H]labelled phentermine or chlorphentermine for varying periods (1 day to 8 weeks). The plasma tissue and concentrations of the drugs were determined. The distribution of phentermine reflected a partition, the tissue: blood ratios remaining constant for the entire period. In contrast, chlorphentermine was increasingly accumulated the longer the treatment lasted, as indicated by rising tissue: blood ratios. Chlorphentermine proved to be tightly bound to tissue components. The highest tissue: blood ratio (160 after 8 weeks) was found in lungs and the highest increase in the accumulation rate (10 fold in 8 weeks) was for the adrenals. These results, together with biochemical and ultra-structural findings, suggest that the highly amphiphilic chlorphentermine induces an impairment of phospholipid metabolism resembling lipidosis.
The inhibition of histamine formation in vivo
Authors: Mole K H , Shepherd D M 
Published: April 2011

Abstract
Histamine formation was measured by the [14C]histamine content of the stomach following injection of [14C]histidine into rats. Carbonyl reagents (e.g. oxyamines) which inactivate pyridoxal phosphate, the co-enzyme of histidine decarboxylase, were the most effective inhibitors of histamine formation in vivo. Although the oximes prepared from imidazol-4(5)-ylmethoxyamine and pyridoxal or pyridoxal phosphate cannot inactivate the co-enzyme, they proved sufficiently potent to merit further study as inhibitors of histamine formation in vivo.
Lesions in the septal nuclei of the rat raise mean systemic arterial pressure and prevent the development of sound-withdrawal hypertension
Authors: Marwood J F , Gan E K , Lockett Mary F 
Published: April 2011

Abstract
Midline lesions in the hippocampal commisure involving the bed nucleus (I) in the forebrains of rats, and lesions which destroyed the medial septal nuclei (III), caused mean systemic arterial pressure to rise by 30–40 mm Hg in female rats of an inbred hypertensive Wistar strain. Lesions involving the anteromedial portions of both lateral septal nuclei (II) raised mean arterial pressure by 10–20 mm Hg. After pentolinium, mean arterial pressure remained raised, by approximately 20 mm Hg, in the 7th postoperative week after lesions I, II and III. The mean systemic arterial pressures of intact and shamlesioned rats rose by 30–40 mm Hg when exposed to reduction of sound level from 65–85 to 35–45 db for 5–6 weeks: this treatment did not influence the mean arterial pressures of rats with lesions I, II or III. The pressor effects of (-)-noradrenaline (0&#x006d;̇25 μg), tyramine (25 μg), angiotensin (10 ng) and vasopressin (0&#x006d;̇2 mU) did not differ in ganglion blocked sham-lesioned and lesioned animals. Organ/body weight ratios did not increase in the lesioned animals; overall, both the pituitary and adrenal weights were just significantly (P &gt; 0&#x006d;̇05) reduced. Lesions II and III caused a significant reduction in kidney weight and lesion II a significant rise in the index of thyroid activity.
The evaluation of the α-adrenoceptor blocking action of indoramin, phentolamine and thymoxamine on the rat and guinea-pig isolated mesenteric vasculature and aortic spiral preparations
Authors: Collis M G , Alps B J 
Published: April 2011

Abstract
The perfused mesenteric vasculature of the rat is a specific, sensitive and stable preparation for the rapid determination of α-adrenoceptor blocking pA2 values. Both types of pA2 determination—the direct determination (Schild, 1947) and the Arunlakshana & Schild (1959) analysis—can be made on this tissue. Indoramin, phentolamine and thymoxamine were evaluated and gave respectively α-block pA2 values of 8&#x006d;̇05, 7&#x006d;̇84 and 6&#x006d;̇47. The pA2 values made on the rat perfused mesentery were compared with those obtained on the rat aorta (indoramin 7&#x006d;̇68, phentolamine 8&#x006d;̇29, thymoxamine 6&#x006d;̇50), the guinea-pig aorta (indoramin 7&#x006d;̇38, phentolamine 7&#x006d;̇64, thymoxamine 6&#x006d;̇93) and the perfused mesenteric bed of the guinea-pig (indoramin 8&#x006d;̇48, phentolamine 7&#x006d;̇51, thymoxamine 6&#x006d;̇97). Statistical analyses of Kb (dissociation constant) values suggest that indoramin has an additional blocking action on resistance vessels, which is not possessed by phentolamine or thymoxamine.