bluuebunny/crossref_metadata_2025 huggingface dataset:
Social–communicative effects of the Picture Exchange Communication System (PECS) in Autism Spectrum Disorders
Authors: Lerna Anna , Esposito Dalila , Conson Massimiliano , Russo Luigi , Massagli Angelo
Published: July 2012

Background: The Picture Exchange Communication System (PECS) is a common treatment choice for non‐verbal children with autism. However, little empirical evidence is available on the usefulness of PECS in treating social–communication impairments in autism.

Aims: To test the effects of PECS on social–communicative skills in children with autism, concurrently taking into account standardized psychometric data, standardized functional assessment of adaptive behaviour, and information on social–communicative variables coded in an unstructured setting.

Methods & Procedures: Eighteen preschool children (mean age = 38.78 months) were assigned to two intervention approaches, i.e. PECS and Conventional Language Therapy (CLT). Both PECS (Phases I–IV) and CLT were delivered three times per week, in 30‐min sessions, for 6 months. Outcome measures were the following: Autism Diagnostic Observation Schedule (ADOS) domain scores for Communication and Reciprocal Social Interaction; Language and Personal–Social subscales of the Griffiths’ Mental Developmental Scales (GMDS); Communication and Social Abilities domains of the Vineland Adaptive Behavior Scales (VABS); and several social–communicative variables coded in an unstructured setting.

Outcomes & Results: Results demonstrated that the two groups did not differ at Time 1 (pre‐treatment assessment), whereas at Time 2 (post‐test) the PECS group showed a significant improvement with respect to the CLT group on the VABS social domain score and on almost all the social–communicative abilities coded in the unstructured setting (i.e. joint attention, request, initiation, cooperative play, but not eye contact).

Conclusions & Implications: These findings showed that PECS intervention (Phases I–IV) can improve social–communicative skills in children with autism. This improvement is especially evident in standardized measures of adaptive behaviour and measures derived from the observation of children in an unstructured setting.
Model‐guided fieldwork: practical guidelines for multidisciplinary research on wildlife ecological and epidemiological dynamics
Authors: Restif Olivier , Hayman David T. S. , Pulliam Juliet R. C. , Plowright Raina K. , George Dylan B. , Luis Angela D. , Cunningham Andrew A. , Bowen Richard A. , Fooks Anthony R. , O'Shea Thomas J. , Wood James L. N. , Webb Colleen T.
Published: July 2012

Infectious disease ecology has recently raised its public profile beyond the scientific community due to the major threats that wildlife infections pose to biological conservation, animal welfare, human health and food security. As we start unravelling the full extent of emerging infectious diseases, there is an urgent need to facilitate multidisciplinary research in this area. Even though research in ecology has always had a strong theoretical component, cultural and technical hurdles often hamper direct collaboration between theoreticians and empiricists. Building upon our collective experience of multidisciplinary research and teaching in this area, we propose practical guidelines to help with effective integration among mathematical modelling, fieldwork and laboratory work. Modelling tools can be used at all steps of a field‐based research programme, from the formulation of working hypotheses to field study design and data analysis. We illustrate our model‐guided fieldwork framework with two case studies we have been conducting on wildlife infectious diseases: plague transmission in prairie dogs and lyssavirus dynamics in American and African bats. These demonstrate that mechanistic models, if properly integrated in research programmes, can provide a framework for holistic approaches to complex biological systems.
What is the effect of peer support on diabetes outcomes in adults? A systematic review
Authors: Dale J. R. , Williams S. M. , Bowyer V.
Published: July 2012

Aim  There is increasing interest in the role that peers may play to support positive health behaviours in diabetes, but there is limited evidence to inform policy and practice. The aim of this study was to systematically review evidence of the impact and effectiveness of peer support in adults living with diabetes.

Methods  We searched the Cochrane Library, MEDLINE, PubMed, EMBASE and CINHAL for the period 1966–2011, together with reference lists of articles for eligible studies. Data were synthesized in a narrative review.

Results  Twenty‐five studies, including fourteen randomized, controlled or comparative trials, met the inclusion criteria. There was considerable heterogeneity in the design, setting, outcomes and measurement tools. Peer support was associated with statistically significant improvements in glycaemic control (three out of 14 trials), blood pressure (one out of four trials), cholesterol (one out of six trials), BMI/weight (two out of seven trials), physical activity (two out of five trials), self‐efficacy (two out of three trials), depression (four out of six trials) and perceived social support (two out of two trials). No consistent pattern of effect related to any model of peer support emerged.

Conclusions  Peer support appears to benefit some adults living with diabetes, but the evidence is too limited and inconsistent to support firm recommendations. There remains a need for further well‐designed evaluations of its effectiveness and impact. Key questions remain over its suitability to the needs of particular individuals, populations and settings, how best to implement its specific components and the sustainability of its effects.
Macroeconomic Impacts of Canadian Immigration: Results from a Macro Model
Authors: Dungan Peter , Fang Tony , Gunderson Morley
Published: July 2012

We use a macro‐econometric forecasting model to simulate the impact on the Canadian economy of a hypothetical increase in immigration. Our simulations generally yield positive impacts on such factors as real gross domestic product (GDP) and GDP per capita, aggregate demand, investment, productivity, and government expenditures, taxes and especially net government balances, with essentially no impact on unemployment. This is generally buttressed by conclusions reached in the existing literature. Our analysis suggests that concern should be with respect to immigrants themselves, as they are having an increasingly difficult time assimilating into the Canadian labour market, and new immigrants are increasingly falling into poverty.
The Human Rights Dimension of REDD
Authors: Savaresi Annalisa
Published: July 2012

Since 2007, parties to the United Nations Framework Convention on Climate Change have been negotiating ‘policy approaches and positive incentives on issues relating to reducing emissions from deforestation and forest degradation in developing countries; and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries’, commonly referred to as ‘REDD’. Although the related mechanism remains in fieri at the time of writing, this article analyzes areas of overlap between REDD and international instruments dealing with the protection of human rights. Far from being merely a theoretical question, this issue has attracted increasing attention as negotiations on REDD progressed. The article gives an account of this ongoing debate, and investigates the scope to create synergies between REDD and human rights instruments.
Cities on edge: Smuggling and neoliberal policies at the Iguazú triangle
Authors: Aguiar José Carlos G.
Published: July 2012

The vision of a borderless world, of people, ideas and products freely circulating within a self‐regulating market, is one that clashes with the emerging legal regime based on the punitive force of the state. After a period of liberalization, seen in the opening of national economies and the promotion of regional trade projects and free‐trade zones, the ambivalence of neoliberalism is manifest in a borderless capitalism that ambiguously depends on the securitization of national borders. Such a changing regime of state intervention is clearly seen at the Iguazú triangle – the tri‐border urban conglomerate that straddles Brazil, Paraguay and Argentina – where the illegality of informal cross‐border trading has been tolerated for decades. Recently stepped up police raids and controls hinder the passage of people and goods, while a new fiscal regime introduced in 2009 in Brazil attempts to regularize cross‐border trafficking by turning petty smugglers into micro entrepreneurs. Petty smugglers – dubbed sacoleiros– can hardly be defined as entrepreneurs and do not constitute an identifiable category of entrepreneurship but, as typical in the informal sector, act on opportunity and need. Drawing on ethnographic research, this paper contextualizes the programmes for border controls and regularizing smuggling inspired by neoliberal ideology in South America.
Do early father–infant interactions predict the onset of externalising behaviours in young children? Findings from a longitudinal cohort study
Authors: Ramchandani Paul G , Domoney Jill , Sethna Vaheshta , Psychogiou Lamprini , Vlachos Haido , Murray Lynne
Published: July 2012

Background:  Factors related to parents and parenting capacities are important predictors of the development of behavioural problems in children. Recently, there has been an increasing research focus in this field on the earliest years of life, however, relatively few studies have addressed the role of fathers, despite this appearing to be particularly pertinent to child behavioural development. This study aimed to examine whether father–infant interactions at age 3 months independently predicted child behavioural problems at 1 year of age.

Method:  A sample of 192 families was recruited from two maternity units in the United Kingdom. Father–infant interactions were assessed in the family home and coded using the Global Rating Scales. Child behaviour problems were assessed by maternal report. Hierarchical and logistic regression analyses were used to examine associations between father–infant interaction and the development of behavioural problems.

Results:  Disengaged and remote interactions between fathers and their infants were found to predict externalising behavioural problems at the age of 1 year. The children of the most disengaged fathers had an increased risk of developing early externalising behavioural problems [disengaged (nonintrusive) interactions – adjusted Odds Ratio 5.33 (95% Confidence Interval; 1.39, 20.40): remote interactions adj. OR 3.32 (0.92, 12.05)]

Conclusions:  Disengaged interactions of fathers with their infants, as early as the third month of life, predict early behavioural problems in children. These interactions may be critical factors to address, from a very early age in the child’s life, and offer a potential opportunity for preventive intervention.
Testing the distinctness of shoot ionomes of angiosperm families using the Rothamsted Park Grass Continuous Hay Experiment
Authors: White Philip. J. , Broadley Martin R. , Thompson Jacqueline A. , McNicol James W. , Crawley Mick J. , Poulton Paul R. , Johnston A. E.
Published: July 2012

See also the Commentary by Willey
Mobile phones as a health communication tool to improve skilled attendance at delivery in Zanzibar: a cluster‐randomised controlled trial
Authors: Lund S , Hemed M , Nielsen BB , Said A , Said K , Makungu MH , Rasch V
Published: July 2012

Please cite this paper as: Lund S, Hemed M, Nielsen B, Said A, Said K, Makungu M, Rasch V. Mobile phones as a health communication tool to improve skilled attendance at delivery in Zanzibar: a cluster‐randomised controlled trial. BJOG 2012;119:1256–1264.

Objective  To examine the association between a mobile phone intervention and skilled delivery attendance in a resource‐limited setting.

Design  Pragmatic cluster‐randomised controlled trial with primary healthcare facilities as the unit of randomisation.

Setting  Primary healthcare facilities in Zanzibar.

Population  Two thousand, five hundred and fifty pregnant women (1311 interventions and 1239 controls) who attended antenatal care at one of the selected primary healthcare facilities were included at their first antenatal care visit and followed until 42 days after delivery. All pregnant women were eligible for study participation.

Methods  Twenty‐four primary healthcare facilities in six districts in Zanzibar were allocated by simple randomisation to either mobile phone intervention (n = 12) or standard care (n = 12). The intervention consisted of a short messaging service (SMS) and mobile phone voucher component.

Main outcome measures  Skilled delivery attendance.

Results  The mobile phone intervention was associated with an increase in skilled delivery attendance: 60% of the women in the intervention group versus 47% in the control group delivered with skilled attendance. The intervention produced a significant increase in skilled delivery attendance amongst urban women (odds ratio, 5.73; 95% confidence interval, 1.51–21.81), but did not reach rural women.

Conclusions  The mobile phone intervention significantly increased skilled delivery attendance amongst women of urban residence. Mobile phone solutions may contribute to the saving of lives of women and their newborns and the achievement of Millennium Development Goals 4 and 5, and should be considered by maternal and child health policy makers in developing countries.
Photofriend: creating visual ethnography with refugee children
Authors: Oh Su‐Ann
Published: July 2012

The political, social and economic context that circumscribes refugees' lives in Thailand has created the need for research that serves the programmatic demands of nongovernmental organisations and multilateral organisations providing services to children in camps along the border. Thus, research has focused on health indicators and schooling, rather than children's everyday lives. As a result, there are few studies that document their lives as told in their own voices. This paper examines the use of visual ethnography as a participatory method that places children's experience of the everyday at the centre of research. It presents the strengths and limitations of the method as a way of eliciting the thoughts, feelings and memories of children who have encountered armed conflict and displacement.
The relationship between tremor and change in brain acetylcholine concentration produced by injection of tremorine or oxotremorine in the rat
Authors: COX B. , POTKONJAK D.
Published: July 2012

The relationship between tremor and change in brain acetylcholine concentration after the injection of tremorine or oxotremorine has been investigated in rats.

Tremorine produced a significant increase in whole brain acetylcholine and in tremor 5 min after injection. After this time tremor subsided but brain acetylcholine continued to increase.

Oxotremorine produced tremor within 30 sec. This became maximal within 5 min of injection and then declined rapidly. The brain acetylcholine concentration showed a significant increase 5 min after injection and continued to increase until 30 min afterwards.
The role of the sympathetic nervous system in the cardiovascular responses to angiotensin in the pithed rat
Authors: FINCH L. , LEACH G. D. H.
Published: July 2012

Angiotensin (200–500 ng, intravenously) produced a biphasic pressor response accompanied by reflex bradycardia in rats anaesthetized with sodium pentobarbitone. In pithed rats and in anaesthetized animals treated with a ganglion blocking agent there was a similar pressor response but an increase in the heart rate which was coincident with the second phase of the pressor response. In pithed preparations an increase in cardiac contractile force accompanied the heart rate changes.

Acute or chronic adrenalectomy did not alter the pressor responses and chronotropic effect of angiotensin in the pithed rat. Propranolol abolished the chronotropic and inotropic action of angiotensin, but left the biphasic pressor response unaltered. Bethanidine, or pretreatment with reserpine, altered the pressor response to a simple rise, and also abolished the chronotropic action of angiotensin. Phentolamine also abolished the second pressor component. Desmethylimipramine produced a marked potentiation of the cardiovascular effects of angiotensin at all dose levels tested (10–500 ng).

It is concluded that in the rat only large doses of angiotensin are capable of indirectly stimulating the sympathetic nerves either at the site of their ganglionic cells or their post‐ganglionic nerve ending.
Steroid potentiation of responses to sympathomimetic amines in aortic strips
Authors: KALSNER STANLEY
Published: July 2012

Responses to catecholamines (adrenaline, noradrenaline, nordefrine) were enhanced by 17β‐oestradiol, progesterone and desoxycorticosterone in untreated and reserpine pretreated aortic strips. Responses to tyramine, believed mediated via endogenous catecholamines, were enhanced only in untreated strips.

Responses to sympathomimetic amines lacking the catechol nucleus (phenylephrine, synephrine, methoxamine) were potentiated inconsistently by the steroids and reserpine pretreatment reduced markedly the frequency of potentiated responses.

Known inhibitors of catechol‐O‐methyl transferase (tropolone, U‐0521, pyrogallol) potentiated responses to catecholamines and abolished the enhancing effects of the steroids—when the steroids were given first, there was no further increase in response to catecholamines on adding inhibitors of catechol‐O‐methyl transferase.

Experiments with the oil‐immersion technique, to eliminate diffusion of drug from the tissue, indicated that 17β‐oestradiol, progesterone and desoxycorticosterone decreased the rate at which aortic strips inactivated adrenaline by Omethylation.

It is concluded that 17β‐oestradiol, progesterone and desoxycorticosterone potentiate responses to catecholamines in aortic strips by inhibiting a major mechanism for their inactivation.
Hormonal regulation of rat seminal vesicle sensitivity to adrenaline, noradrenaline, acetylcholine and acetyl‐β‐methylcholine
Authors: PICARELLI ZULEIKA P. , VALLE J. R.
Published: July 2012

The influence of the hormonal condition of rats on the responsiveness of their seminal vesicles to drugs was investigated by determining pD2 and α values for adrenaline, for noradrenaline, for acetylcholine and for acetyl‐β‐methyl‐choline on isolated vesicles of normal, of castrated, and of oestradiol‐treated castrated rats.

pD2 values of adrenaline, of noradrenaline, of acetylcholine and of acetyl‐β‐methylcholine acting on seminal vesicles of castrated or of oestradiol‐treated castrated rats were greater than the corresponding values obtained on the organs of normal rats. The differences were significant at the level P < 0.001.

Similar results were obtained for the relative intrinsic activity of noradrenaline and acetyl‐β‐methylcholine.

Consequently affinity of adrenaline, noradrenaline, acetylcholine and of acetyl‐β‐methylcholine for their corresponding receptors and the stimulus produced by each unit of the noradrenaline‐receptor or acetyl‐β‐methylcholine‐receptor complex were enhanced.

The data indicate that an increase in the sensitivity of the smooth musculature of seminal vesicles to adrenaline and noradrenaline as well as to acetylcholine and acetyl‐β‐methylcholine is obtained by castration, or by treatment with oestradiol following castration.
The pharmacological nature of the response of the reserpinized guinea‐pig vas deferens to postganglionic nerve stimulation
Authors: BELL C.
Published: July 2012

. Intracellular recordings from single smooth muscle cells of the guinea‐pig vas deferens have been made after depletion of neuronal stores of noradrenaline by chronic reserpine treatment.

. Junctional responses to postganglionic hypogastric nerve stimulation were depressed, but large excitatory junction potentials (EJPs) and action potentials could still be evoked by stimulation at 1–2 c/s.

. These junctional responses were not reduced by the presence of hyoscine (5 × 10−7g/ml.), but were greatly depressed by the presence of bretylium (2 × 10−6g/ml.).

. Even in the presence of bretylium, junctional responses leading to action potentials could still be evoked by using high voltages of stimulation.

. It is concluded that when neuronal noradrenaline stores have been depleted by reserpine some noradrenaline is still available for release by nerve stimulation.

. It is further concluded that if the non‐adrenergic component of the response of the guinea‐pig vas deferens to nerve stimulation is cholinergic, this component is resistant to blockade by hyoscine.
Blockade of biogenic amine synthesis: its effect on the responses to leptazol and dexamphetamine in rats
Authors: SPENCER P. S. J. , TURNER T. A. R.
Published: July 2012

. The convulsive effects of leptazol in the rat are potentiated by prior treatment with dexamphetamine.

. An intact dopamine synthesis is necessary for the potentiation of the convulsive action of leptazol.

. An intact noradrenaline synthesis is not necessary for this action of amphetamine, as long as the dopamine synthesis is intact.

. An intact 5‐hydroxytryptamine synthesis is not necessary for the potentiation to be shown.

. Blockade of either noradrenaline, dopamine or 5‐hydroxytryptamine synthesis has no direct effect on leptazol convulsions.

. It is possible that it is an intact 3–4 dihydroxyphenylalanine (dopa) synthesis rather than an intact dopamine synthesis that is involved.
Secretion from the cortex‐free bovine adrenal medulla
Authors: SCHNEIDER F. H.
Published: July 2012

. The isolated bovine adrenal medulla was prepared from whole glands by careful removal of the cortex. The tissue was perfused with physiological salt solution and stimulated with a variety of secretogogues.

. Catecholamines were secreted from the tissue upon stimulation with carbamylcholine, nicotine sulphate, acetylcholine bromide, histamine dihydrochloride, (+)‐amphetamine sulphate and potassium chloride.

. Carbachol‐induced secretion of catecholamines was reduced in the presence of either hexamethonium bromide or tetracaine hydrochloride, during perfusion with calcium‐free perfusion fluid, or during perfusion at low temperature.

. Stimulation of the medulla with carbachol also led to secretion of chromaffin granule protein and acid deoxyribonuclease. The relationships between catecholamines secreted and the amounts of these proteins secreted were similar to the corresponding values for the perfused whole bovine adrenal gland. Perfusate lactate dehydrogenase activity and perfusate haemoglobin content were unchanged after carbachol stimulation.

. It is concluded that there are no differences in the mechanisms for catecholamine secretion from the cortex‐free perfused medulla and the perfused whole gland.
Rapid method for the determination of 5‐hydroxytryptamine and 5‐hydroxyindoleacetic acid in small regions of rat brain
Authors: Curzon G. , Green A. R.
Published: July 2012

A rapid and sensitive method for measuring 5‐hydroxytryptamine and 5‐hydroxyindoleacetic acid, using o‐phthalaldehyde and L‐cysteine, is presented, enabling both compounds to be measured in small areas of rat brain.
Cardio‐selective β‐adrenoceptor blockade and the coronary circulation
Authors: Adam K. R. , Boyles Susan , Scholfield P. C.
Published: July 2012

After blockade of myocardial, but not coronary vascular β‐adrenoceptors by practolol, cardiac sympathetic stimulation or exo‐genously administered noradrenaline gave rise coronary vasoconstriction, possibly due to stimulation of coronary a‐adrenoceptors.
The possible role of adenosine in the coronary dilator action of some pyrimidopyrimidines and pteridines
Authors: NOTT M. W.
Published: July 2012

The abilities of some pyrimidopyrimidines (including dipyridamole) and pteridine derivatives to potentiate heart block produced by adenosine in the guinea‐pig and to produce coronary dilatation in kitten hearts were investigated.

The results demonstrated a correlation between adenosine potentiating and coronary dilating activities of the compounds studied, and are therefore compatible with the concept that compounds of the dipyridamole type owe their coronary dilator activity to potentiation of endogenous adenosine.
A pharmacological analysis of the peristaltic reflex in the isolated colon of the guinea‐pig or cat
Authors: CREMA A. , FRIGO G. M. , LECCHINI S.
Published: July 2012

The peristaltic reflex in the colon was elicited by a localized intraluminal stimulus. The contractile response of the longitudinal coat, which consists of two phases, begins before the start of propulsion. Although the contractions of the longitudinal and circular musculature are usually associated, they may be independent of each other. In particular, the longitudinal contraction does not seem to be necessary for propulsion.

Both the longitudinal reflex contraction and the segmental responses of the circular muscle to distension, namely a contraction above and a relaxation below the bolus, are abolished by tetrodotoxin and ganglion blocking agents.

In the guinea‐pig, longitudinal and circular reflex contractions are usually resistant to antimuscarine, antihistamine and antitryptamine drugs but in the cat they are abolished by antimuscarine drugs. In both species, however, atropine and hyoscine can impair propulsion by blocking selectively the descending inhibition. In the cat, it is possible to find doses which abolish the descending inhibition without affecting the contractile responses of the longitudinal and circular muscle.

Sympathetic denervation and pretreatment with reserpine do not affect the propulsive activity. The maintenance of the descending inhibition in denervated organs suggests that the inhibitory neurones to the circular muscle are not adrenergic.

On the basis of the effects of drugs, the possible nervous mechanism subserving the polarity of propulsion has been examined. Such a mechanism seems to require an inhibitory pathway involving muscarinic receptors at some point.

Pelvic nerve stimulation facilitates propulsive activity. The effect of transmural stimulation is different at low and at high frequencies of stimulation. The inhibitory effect of sympathetic stimulation on the reflex responses seems to be due mainly to an action on intrinsic nervous structures.
Renal tubular flow dynamics during angiotensin diuresis in the rat
Authors: FINBERG J. P. M. , PEART W. S.
Published: July 2012

Tubular size and lissamine green transit times were measured in rat kidneys undergoing a diuretic response to angiotensin II (05 μg/kg per min), and compared with the changes observed during diuresis induced by osmotic diuretics, noradrenaline and chlorothiazide.

Angiotensin always caused a marked prolongation in proximal and distal tubular transit times; individual distal convolutions were coloured for prolonged periods, and lissamine green appeared in high concentration in distal tubules.

Marked changes were observed in superficial tubular calibre during a stable diuretic response to angiotensin. Where distal tubular diameter was normal for the rate of urine flow, proximal tubular volume was generally reduced. In a number of experiments, however, distal tubules were markedly dilated, and in these cases proximal tubular volume was also often increased. Angiotensin may therefore be capable of causing a degree of internal hydronephrosis in the rat kidney.

Prolongation of dye transit times, and the appearance of a concentrated lissamine green bolus in distal tubules, was suggestive of a decreased superficial nephron flow rate, indicating that the diuretic effect of angiotensin may take place only through deeper nephrons.
Comparison of the bronchodilator and cardiovascular actions of salbutamol, isoprenaline and orciprenaline in guinea‐pigs and dogs
Authors: DALY M. J. , FARMER J. B. , LEVY G. P.
Published: July 2012

Bronchodilator and cardiovascular actions of salbutamol and isoprenaline have been compared in guinea‐pigs and dogs. Orciprenaline was also included in some experiments.

All three drugs antagonized acetylcholine‐induced increases in pulmonary resistance. In addition they increased heart rate and decreased arterial blood pressure.

Compared with isoprenaline, salbutamol has relatively stronger actions on bronchial and vascular β‐adrenoceptors than on cardiac β‐adrenoceptors, on which its action is very weak. In contrast, orciprenaline has similar potencies on β‐adrenoceptors in these three tissues.

The positive chronotropic potency of intravenously or orally administered salbutamol was increased in conscious dogs. These heart rate responses to salbutamol were probably mainly reflex in origin.

Salbutamol and orciprenaline were both longer acting than isoprenaline.

The results support the idea of two distinct groups of β‐adrenoceptors. Salbutamol differentiates between bronchial and vascular β2‐adrenoceptors on the one hand and cardiac β1‐adrenoceptors on the other. Isoprenaline and orciprenaline do not differentiate between β1‐ and β2‐adrenoceptors.
Pharmacological properties of amino‐oxyacetic acid in the chicken
Authors: OSUIDE G.
Published: July 2012

The effects of amino‐oxyacetic acid (AOAA) on the central nervous system and on skeletal muscle have been examined in the chicken.

AOAA had both anticonvulsant and convulsant effects, depending on the dose, as in other species.

The convulsant effect, accompanied by EEG spiking, decreased rapidly with increase in age of young chicks.

The convulsant effect was exerted primarily through supraspinal centres.

Of control depressants tested, only troxidone and small doses of AOAA afforded significant protection against AOAA seizures.
Analysis of the inhibition of pethidine N‐demethylation by monoamine oxidase inhibitors and some other drugs with special reference to drug interactions in man
Authors: CLARK B. , THOMPSON J. W. , WIDDRINGTON G.
Published: July 2012

N‐Demethylation of pethidine was studied in microsomal suspensions from unstarved male rat liver and the N‐demethylase identified as belonging to the class of hepatic microsomal mixed function oxidases.

A study of the structure/action relationships of compounds inhibiting pethidine N‐demethylase revealed that hydrazine derivatives including phenylhydrazine, methylphenylhydrazine and mebanazine were all potent competitive inhibitors.

Pethidine N‐demethylase was only slightly inhibited by histamine and amphetamine but not by adrenaline and ephedrine nor by several miscellaneous compounds including piperidine, N‐ethylpiperidine, N‐methylpiperidine, N‐methylammonium, hydrallazine or pethidinic acid.

Several psychotropic drugs were all found to be potent competitive inhibitors of pethidine N‐demethylase. These included monoaminoxidase inhibitors (the most active being nialamide and phenoxypropazine [Ki = 0·01 mm]; the least active iproniazid [Ki = 1·05 mm]); the tranquillizers promazine, propiomazine and chlorpromazine and tricyclic antidepressants (opipramol [Ki = 0·01 mm], imipramine [Ki = 0·03 mm], desipramine [Ki = 0·03 mm] and amitryptyline [Ki = 0·03 mm]). Hydrocortisone [Ki = 0·3 mm], prednisolone [2·8 mm] and nalorphine [0·07 mm] were also inhibitors, whilst SKF 525A was the most active of all [Ki = 0·002 mm].

These results are discussed in relation to the clinically observed drug interactions which may occur between monoamineoxidase inhibitors and pethidine. It is concluded that since many different groups of drugs, including monoamineoxidase inhibitors, tranquillizers, tricyclic antidepressants, steroids, nalorphine, SKF 525A and barbiturates compete for cytochrome P450 reductase, it is possible that this mechanism may account, at least in part, for the observed interactions of these various drugs in man.
Effects of 5‐hydroxytryptamine on isolated strips of the guinea‐pig stomach
Authors: YAMAGUCHI T.
Published: July 2012

The effects of 5‐hydroxytryptamine (5‐HT) on isolated strips of the longitudinal and circular muscles of the guinea‐pig stomach were investigated.

5‐HT (0·1–1 μg/ml) increased the resting tension of the longitudinal muscle while it decreased that of the circular muscle. These effects were blocked by lysergic acid diethylamide (LSD), but were not affected by tetrodotoxin, hyoscine or morphine.

Electrical stimulation caused contraction in the longitudinal muscle, and contraction followed by relaxation in the circular muscle. In both the longitudinal and circular muscles, the evoked contractions were potentiated by 5‐HT. This effect was blocked by tetrodotoxin, hyoscine and morphine, but was not affected by LSD.

It is concluded that, in the stomach as well as the intestine of the guinea‐pig, there are two kinds of 5‐HT receptors: the morphine‐sensitive M receptor is situated on the intramural nerves and the D‐receptor on the smooth muscle cells.
Measurement of inflammation in man and animals by radiometry
Authors: COLLINS A. J. , RING E. F. J.
Published: July 2012

A radiometer is described, which is sensitive to infrared radiation in the range 0–25 μm, and which, after calibration with a black body standard can be used as a non‐contact, fast reading thermometer.

An example of acute joint inflammation in a patient with rheumatoid arthritis is described. The temperatures over the joint measured by radiometry, followed inflammatory changes in the joint effusion.

Using rats, the method of measuring inflammation by radiometry was compared with measurements of increase in joint size. Changes measured by radiometry preceded changes shown by increase in joint size.

The radiometer method was able to demonstrate the effect of an anti‐inflammatory drug, given orally, against carrageenin inflammation.

The procedure was found to be an accurate means of measuring inflammation and the anti‐inflammatory effects of drugs. It was faster and less tedious than the other methods for the quantitative measurement of inflammation in man and animals.
Effects of adrenaline, isoprenaline and histamine on transsinusoidal fluid filtration in the cat liver
Authors: GREENWAY C. V. , LAUTT W. W.
Published: July 2012

Hepatic volume was recorded by a plethysmographic technique in cats anaesthetized with pentobarbitone. It has been shown previously that during an increase of hepatic venous pressure in this preparation, there is a maintained filtration of fluid from the sinusoids into the plethysmograph. The rate of this filtration is directly proportional to the increase in hepatic venous pressure. Infusions of drugs during this period of steady filtration provide a sensitive measure of the effects of the drugs on transsinusoidal fluid transfer.

Infusions of adrenaline, isoprenaline and histamine had no effect on the steady transsinusoidal filtration produced by an increased hepatic venous pressure. It is concluded that these agents do not change sinusoidal hydrostatic pressure by more than 1·5 mmHg (1 mmHg ≡ 1·333 mbar) even though they alter hepatic arterial and portal flows. They do not change sinusoidal surface area by more than 20% and histamine does not change sinusoidal permeability.

The data are discussed in the light of current theories on the application of Starling's hypothesis to the liver sinusoids and to muscle capillaries. The postsinusoidal resistance appears to be very low in the liver and it does not increase during contraction of the capacitance vessels. The liver does not have presinusoidal sphincters, and closed sinusoids analogous to closed capillaries in skeletal muscle do not occur. The major factor controlling hepatic transsinusoidal fluid movements in the anaesthetized cat is hepatic venous pressure.
Some aspects of the inhibition of the action of antidiuretic hormone by lithium ions in the rat kidney and bladder of the toad Bufo marinus
Authors: HARRIS CAROL A. , JENNER F. A.
Published: July 2012

The effect of intravenous infusions of various ions on the antidiuretic action of antidiuretic hormone has been studied in rats.

Lithium (13 mmol/l.) reversibly inhibits the antidiuretic responses. Similar concentrations of potassium, rubidium, strontium, magnesium, choline and calcium do not. Lithium has a similar effect on the antidiuretic activity of oxytocin.

The inhibition is not simply related to blood nor whole body lithium concentrations.

Lithium (2 mmol/1.) in contact with the serosal surface also inhibits the transport of water facilitated by either 0·5 u/l. antidiuretic hormone or 1·1 mmol/l. cyclic adenosine monophosphate in the isolated toad bladder.

Choline (2 mmol/l.) on the serosal surface also inhibits the transport of water facilitated by vasopressin in the toad bladder.
Comparison of blockade at α‐adrenoceptors by thymoxamine and phentolamine in peripheral arteries and veins of man
Authors: COLLIER J. G. , NACHEV CH. , ROBINSON B. F.
Published: July 2012

The antagonism at α‐adrenoceptors by thymoxamine and phentolamine of the response to noradrenaline was investigated in the limb veins and arteries of man.

Brachial artery infusions of thymoxamine (40 μg/min) produced rises in resting arterial flow of up to 100%. When infused mixed with noradrenaline, thymoxamine (40 μg/min) attenuated the blood flow response to noradrenaline. Blockade was of a similar degree to that which occurred following a 10 min infusion of phentolamine (40 μg/min).

Local intravenous infusion of thymoxamine (400–2,000 ng/min) mixed with noradrenaline attenuated the venoconstrictor response to noradrenaline. The degree of attenuation was similar to that seen after a 10 min infusion of phentolamine (500 ng/min). Blockade after thymoxamine did not last longer than 16 minutes. Neither thymoxamine nor phentolamine altered resting venous compliance.

Local intravenous infusions of thymoxamine (500 ng/min) and phentolamine (500 ng/min) abolished the sympathetically mediated venoconstriction produced by overbreathing.

Systemic injection of thymoxamine (0·1 mg/kg) did not block the reduction in forearm arterial flow produced by locally infused noradrenaline. In two out of three experiments, however, it produced some antagonism of noradrenaline induced venoconstriction. Systemic phentolamine (5 mg) blocked the effect of noradrenaline in the arterial bed, but antagonized its actions in the veins in only one out of three experiments.
Effects of dopamine on the conductance of perfused vascular beds of the chloralosed cat
Authors: HAMILTON T. C.
Published: July 2012

Dopamine produced vasoconstriction followed by secondary vasodilatation in the perfused cat hindquarters and splanchnic region. Low doses produced only vasodilatation in the splanchnic region.

Phenoxybenzamine abolished, while desipramine and cocaine potentiated, the vasoconstrictor and secondary dilator actions of dopamine.

After phenoxybenzamine, dopamine produced only vasodilatation in both the hindquarters and splanchnic region, being more effective in the latter.

Haloperidol, but not propranolol, atropine or mepyramine, antagonized dopamine‐induced vasodilatation.

Dopamine differs from other catecholamines in that, while its cardiac effects are mediated by a β‐adrenoceptive mechanism, its vasodilator effects are not.

The results support the concept of a specific receptor mediating dopamine vasodilatation.
Studies on the possible role of brain histamine in behaviour
Authors: GERALD M. C. , MAICKEL R. P.
Published: July 2012

The possible role of brain histamine in behavioural performance was studied in rats using thirst‐induced water consumption, continuous (Sidman) avoidance, and reinforcement withdrawal test systems.

Parenteral administration of a variety of antihistamines to rats decreased thirst‐induced water consumption; this effect could be antagonized by administration of histamine directly into the brain by a ventricular cannula.

When intraventricular doses of histamine were administered to rats at weekly intervals, an adaptation was seen in the effects of the amine on continuous avoidance behaviour. With succeeding doses, the initial period of depression of avoidance responding was shortened and the subsequent rebound stimulation disappeared.

The results support the hypothesis that histamine in the brain is involved in several behavioural phenomena.
Salivation induced by prostaglandin F2α and modification of the response by atropine and physostigmine
Authors: HAHN R. A. , PATIL P. N.
Published: July 2012

Administration of PGF2α to the anaesthetized dog produced dose‐related salivation accompanied by weak pressor and negative cardiac chronotropic effects. Injection of PGE1 did not produce salivation.

Electrical stimulation of the chorda tympani nerve or injection of PGF2α produced salivary responses which were not affected by pretreatment with phentolamine, but were abolished by pretreatment with atropine. Treatment with hexamethonium reduced the response to nerve stimulation but did not alter the response to PGF2α.

Pretreatment with physostigmine augmented the salivary response to both nerve stimulation and PGF2α.

These experiments suggest that salivation produced by PGF2α is probably due in part, to liberation of acetylcholine from cholinergic nerve terminals. These results are consistent with previously proposed modulatory functions of prostaglandins on neurotransmission.
Nerve‐mediated inhibition of mechanical activity in rabbit duodenum and the effects of desensitization to adenosine and several of its derivatives
Authors: WESTON A. H.
Published: July 2012

. Inhibition of mechanical activity in longitudinal muscle strips of rabbit duodenum was induced by perivascular and intramural nerve stimulation.

. The effects of perivascular stimulation were abolished by phentolamine + propranolol, guanethidine, reserpine and by tetrodotoxin. The effects of intramural stimulation were abolished only by tetrodotoxin.

. Noradrenaline, phenylephrine, isoprenaline, adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and adenosine each produced an inhibition of mechanical activity. The relative potencies of these agonists were noradrenaline>isoprenaline>phenylephrine>ATP>ADP>adenosine>AMP.

. Exposure of tissues to high concentrations of either ATP or adenosine desensitized the tissue to further exposure to ATP, ADP, AMP and adenosine, whilst the inhibitory effects of noradrenaline, phenylephrine and isoprenaline and of perivascular and intramural stimulation were unaffected. The effects of desensitization were reversible.

. It was concluded that the effects of intramural stimulation were mediated neither by noradrenaline nor by adenosine or its derivatives.
The effect of β‐adrenoceptor blockade on human sweating
Authors: ALLEN JUDITH A. , JENKINSON D. J. , RODDIE I. C.
Published: July 2012

Changes in cutaneous water loss were followed by continuously monitoring total body weight loss.

Sweating was induced in normal subjects by raising the environmental temperature or by subjecting them to the emotional stress of mental arithmetic.

Propranolol in a dosage of 0·15 mg/kg body weight intravenously had no significant effect on either thermal or emotional sweating, whereas thermal sweating was completely blocked temporarily by administration of atropine 2·4 mg intravenously.

It is concluded that β‐adrenoceptor blockade has no effect on physiological sweating in normal people.
The effects of hallucinogenic drugs on maze exploration in the rat over a 24 hour period
Authors: DAVIES J. A. , REDFERN P. H.
Published: July 2012

The variation with clock‐hour in the behaviour of naive rats in a Y‐maze has been recorded.

The number of entries recorded was highest during the light period while the number of faecal boluses was highest during the dark period. Rearing showed a biphasic periodicity.

The responses to LSD, mescaline and amphetamine also showed significant variation with clock‐hour.

In general, amphetamine, 1·25 mg/kg, increased the number of entries and the number of rears, the effect being greatest at the end of the light period. LSD, 100 μg/kg, and mescaline, 12·5 mg/kg, decreased the number of entries and the number of rears.

All three drugs decreased the number of faecal boluses. The possible significance of these responses in terms of an effect on the emotional state of the animals is discussed.
THE EFFECT OF INDOMETHACIN ON THE RELEASE OF PROSTAGLANDIN E2 AND ACETYLCHOLINE FROM GUINEA‐PIG ISOLATED ILEUM AT REST AND DURING FIELD STIMULATION
Authors: BOTTING J.H. , SALZMANN R.
Published: July 2012

Guinea‐pig ileum suspended in Krebs solution showed a continuous increase of tone which was lost by changing the bath fluid. Prostaglandin E2 was released from the ileum during incubation, and its concentration in the bath fluid appeared to correlate with the increase in tone.

Supramaximal field stimulation (10 Hz) resulted in increased release of prostaglandin E2 from the ileum. At lower rates of stimulation, the increase in the release of E2 compared with the resting output was not significant.

Indomethacin (1 and 10 μg/ml) produced a significant, dose‐related reduction of the amount of prostaglandin E2 measured in the bath fluid at rest and with field stimulation. Indomethacin inhibited the contraction of the ileum during incubation in Krebs solution.

Indomethacin (10 and 20 μg/ml) had no significant effect on the release of acetylcholine during field stimulation, but reduced the resting output of acetylcholine from guinea‐pig ileum in some experiments.

The results are discussed in the context of the role ascribed to prostaglandins as physiological modulators in transmitter release. No evidence for a prostaglandin‐mediated negative feedback mechanism on acetylcholine release was obtained.
GASTRIN RELEASE BY BOMBESIN IN THE DOG
Authors: BERTACCINI G. , ERSPAMER V. , MELCHIORRI P. , SOPRANZI N.
Published: July 2012

The intravenous infusion of bombesin produced in intact dogs and, more strikingly in dogs provided with gastric fistulae a sharp increase in plasma levels of immunoreactive gastrin and at the same time a stimulation of gastric acid secretion. Gastrin response was correlated with the dose of bombesin from approximately 0.1 μg kg−1 h−1 (threshold) to 1 μg kg−1 h−1 (maximum gastrin release).

Atropine and metiamide reduced or inhibited gastric acid secretion stimulated by bombesin, but did not affect the rise in gastrin levels.

Acidification of the whole stomach or of a perfused antral pouch caused a reduced or delayed response to bombesin. However, the inhibitory effect of acidification could be surmounted by prolonging the duration of bombesin infusion.

Antrectomy greatly reduced the rise in gastrin levels and the increase in acid gastric secretion produced by bombesin, but left unaffected the gastric secretagogue effect of pentagastrin.

It is concluded that bombesin is a potent releaser of gastrin from the antral mucosa.

The possible influence of the renal effects evoked by bombesin in the dog on the gastrin response to the polypeptide is discussed.
ANTAGONISM OF TONE AND PROSTAGLANDIN‐MEDIATED RESPONSES IN A TRACHEAL PREPARATION BY INDOMETHACIN AND SC‐19220
Authors: FARMER J.B. , FARRAR D.G. , WILSON J.
Published: July 2012

The effects of the prostaglandin synthetase inhibitor, indomethacin and the prostaglandin antagonist SC‐19220 (1‐acetyl‐2‐[8‐chloro‐10,11‐dihydrodibenz (b, f) (1,4)oxazepine‐10‐carbonyl] hydrazine), were examined on the tone of the guinea‐pig isolated tracheal preparation and on the responses of the preparation to prostaglandin F2α, arachidonic acid and methacholine.

Indomethacin (0.05–1.6 μg/ml) produced a long‐lasting inhibition of the intrinsic tone of the tracheal preparation and of the contractile responses to arachidonic acid. Much higher concentrations of indomethacin also reduced the responses of the preparation to methacholine. This effect was readily reversible and appeared to be unrelated to the action on tone.

The contractile responses of the preparation to prostaglandin F2α were enhanced by low concentrations of indomethacin (1–5 μg/ml) and inhibited by higher concentrations (2.5–80 μg/ml).

SC‐19220 was shown to inhibit responses of the preparation to prostaglandin F2α in concentrations (0.1–1 μg/ml) which had no effect on responses to methacholine. Similar concentrations also inhibited the intrinsic tone of the preparation and the responses to arachidonic acid.

The evidence suggests that prostaglandins may be involved in the maintenance of tone of the guinea‐pig isolated tracheal preparation.