Fluid collections detected by ultrasound following uncomplicated colorectal surgery

The aim of the study was to assess the incidence and site of intraperitoneal fluid collections following uncomplicated colorectal surgery and to identify factors relating to the presence of such collections. 38 patients (22 males) with a mean age of 67 years (range 38-85 years) undergoing uncomplicated colorectal procedures were studied prospectively. Patients underwent abdominal and pelvic ultrasound on Day 3 and Day 7 following surgery. The number, site and volume of collections were recorded. Ultrasound-detected fluid collections were present in 26% on Day 3 and 25% on Day 7 following laparotomy. The presence of a collection was not related to the amount of residual volume after peritoneal lavage with normal saline prior to operative closure, to intraoperative blood loss or to the presence of drains. The right upper quadrant was the commonest site of intraperitoneal collections. In the absence of additional clinical signs, the presence of such collections is not an indication for intervention.

Diet and compliance in phenylketonuria

In phenylketonuria, compliance and diet is a difficult issue; it is hard to quantify and is under-researched. It is influenced by many factors. Failure to consume prescribed quantity of protein substitute has been commonly reported and is probably affected by their acceptability, format and timing of administration. There are few reports documenting actual phenylalanine intake and blood phenylalanine control, but it is possible that the more rigorous systems for allocation of phenylalanine are associated with worse compliance. The dry, hard and insipid nature of many low protein products may lead to their under usage and consequent boredom and hunger. The diet becomes increasingly harder to maintain as children grow older and seek fewer constraints in their meals.

CONCLUSION

In phenylketonuria, encouraging adherence to diet requires continual education, reinforcement and support from the family and professionals within the support team.

The relationship of genotype to cognitive outcome in galactosaemia

AIMS

To evaluate the cognitive outcome of a cohort of children with galactosaemia in relation to genotype.

METHODS

The cohort was drawn from children notified to the British Paediatric Surveillance Unit galactosaemia study which ran from 1988 to 1990. Cognitive outcome was assessed using the Wechsler Intelligence Scale for Children or the Wechsler Preschool and Primary Scale of Intelligence. Parents completed a questionnaire detailing educational status, and the attending paediatrician returned a questionnaire regarding age at diagnosis and biochemical outcome over the previous two years.

RESULTS

A total of 45 children were genotyped: 30 were homoallelic for the Q188R mutation, the remainder being heteroallelic for Q188R with K285N (n = 4), L195P (n = 4), or other mutations (n = 7). Psychometric evaluation was available in 34 cases: mean full scale IQ was 79, verbal quotient 79, and performance quotient 82. Genotype was not related to galactose-1-phosphate (Gal-1-P) concentrations. However, children homoallelic for the Q188R mutation had significantly lower IQ scores than those who were heteroallelic (73. 6 v 94.8). This difference was independent of social and demographic influences and Gal-1-P concentrations over the previous two years.

CONCLUSIONS

In children with galactosaemia, cognitive outcome appears to relate to genotype rather than metabolic control, as reflected by Gal-1-P concentrations. The value of measuring Gal-1-P concentrations routinely once successfully established on a galactosaemia diet is questionable as concentrations do not appear to affect outcome. In the UK population, homozygosity for the Q188R mutation is invariably associated with a poor outcome, and there is evidence that variability in neurocognitive outcome is at least part dependent on allelic heterogeneity.

Clinical pharmacokinetics and therapeutic drug monitoring of sirolimus

BACKGROUND

Sirolimus is a novel macrocyclic antibiotic that has an immunosuppressive mechanism of action distinct from that of cyclosporine and tacrolimus.

OBJECTIVE

The objective of this report is to provide an overview of the clinical development of sirolimus with emphasis on the mechanism of immunosuppressive activity, prevention of acute renal allograft rejection, clinical pharmacokinetics, concentration-effect relationships, and therapeutic drug monitoring (TDM).

RESULTS

Pharmacokinetic studies in adult renal transplant patients have shown that sirolimus may be characterized as a drug with rapid absorption (t(max) = 1 to 2 hours), low systemic availability (F = 14%), linear dose proportionality (2 to 24 mg), extensive partitioning into formed blood elements (B/P = 36), large apparent volume of distribution (1.7 L/kg), prolonged terminal half-life (62 hours), and large intersubject (CV = 52%) and intrasubject (CV = 26%) variability in oral-dose clearance. Results from phase 111 pivotal trials showed that sirolimus (2 or 5 mg/d) reduced acute renal graft rejection (generally, P < 0.01) without TDM. Although TDM may not be required for a regimen consisting of full-dose cyclosporine and corticosteroids with sirolimus 2 mg/d (4 hours after cyclosporine), it may be warranted in patients (1) with hepatic impairment, (2) who are young children, (3) who are receiving concurrent doses of strong CYP3A/p-glycoprotein inhibitors or inducers, (4) in whom cyclosporine dosing is markedly reduced or discontinued, and (5) who are at a high risk for rejection. A whole-blood sirolimus therapeutic window of 5 to 15 ng/mL (measured by microparticle enzyme immunoassay) is recommended for patients at standard risk of rejection. The large intrapatient variability observed in trough sirolimus concentrations indicates that dose adjustments should be optimally based on more than a single trough sample. Because of the time required to reach steady state, sirolimus dose adjustments would optimally be based on trough levels obtained >5 to 7 days after a dose change.

CONCLUSIONS

The effective use of sirolimus in an immunosuppressive regimen for the prevention of acute renal allograft rejection requires an understanding of the drug's clinical pharmacokinetics, concentration/adverse-effect relationship, concentration-efficacy relationship, and TDM.

Parkinson's disease and aided AAC: some evidence from practice

Clinical observation that people with Parkinson's disease (PD) seem to have different training needs from other adult client-groups in developing effective use of aided augmentative and alternative communication (AAC) was the catalyst for this study. There is little good-quality research evidence available on the effectiveness (or lack of effectiveness) of aided AAC use by those with PD. One of the main aims of this preliminary study, therefore, was to elicit the experiences and attitudes of speech and language therapists in this specific area of their practice as the basis for future efficacy research and clinical practice. Thirty speech and language therapists were questioned about their experience of introducing low- and high-tech AAC devices to this client-group. Of particular interest was the discovery of the factors identified by the therapists as influencing their introduction of aided AAC to someone with PD and affecting implementation and successful use. The factors reported were both disease-specific (e.g. motor problems) and more general factors (e.g. carer support) relevant to the process of introducing aided AAC to other adult client-groups. Implications for future research and practice are discussed. Some research questions are posed and the inclusion of people with PD and their carers in practice development is promoted.

Role of endothelium/nitric oxide in atypical beta-adrenoceptor-mediated relaxation in rat isolated aorta

The role of endothelium in the modulation of classical and atypical beta-adrenoceptor-mediated vasorelaxation was investigated in ring preparations of rat isolated thoracic aorta. Rings were pre-constricted with a sub-maximal concentration of noradrenaline (1 microM) and relaxant responses to cumulative concentrations of beta-adrenoceptor agonists obtained. Endothelium removal or pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM) or 1H-[1,2,4] oxadiazolol[4,3,-a] quinoxalin-1-one (ODQ, 10 microM) significantly reduced the relaxant effects of isoprenaline, but had less effect on relaxant responses to the atypical beta-adrenoceptor agonist, (+/-)-4-(3-t-butylamino-2-hydroxypropoxy)-benzimidazol-2-one hydrochloride (CGP 12177A). Sodium nitroprusside (3 nM) shifted the isoprenaline concentration-response curve to the left and restored the attenuated responses in the presence of L-NAME back to control levels. Sodium nitroprusside had little effect on the CGP 12177A concentration-response curve. The results show that the endothelium/nitric oxide (NO) pathway modulates beta-adrenoceptor-mediated vasorelaxation in rat aorta and that classical beta-adrenoceptors are modulated to a greater extent than atypical beta-adrenoceptors.

Cerebrovascular accident clinical pathway

The cerebrovascular accident (CVA) clinical pathway project was selected to complement the work already underway within the West Moreton Health Services District such as the development of a continuum of care model, revision of work practices to complement the new hospital redevelopment and encouraging team and evidence-based approaches to problem solving. Specific objectives were set for the project along with a detailed evaluation plan. A steering group was convened to run the project and a full time project officer was appointed. At the end of the 12 month period all the objectives were met. Specific achievements included a reduction in the overall average length of stay for those patients who experience CVA, improved clinical outcomes and a more effective use of resources. Quality of care has been improved through the preparation of specialized clinical pathway documentation, education packages, patient surveys, focus groups, independent reviews and benchmarking. Complementing these measures has been a series of process changes and environmental modifications. Furthermore, good working relationships have been established with private sector providers of health care and other external bodies. The development of the CVA clinical pathway at the Ipswich Hospital has meant timely referrals and a streamlined assessment and referral process to get patients into rehabilitation sooner. It has promoted good communication between, and recognition of, the professional roles of various team members and has put the patient back at the centre of the care process.

Angiographic embolization for major haemorrhage after upper gastrointestinal surgery

AIMS: Severe postoperative haemorrhage after upper gastrointestinal surgery is a serious complication. This study examined the effectiveness of selective mesenteric angiography (SMA) in localizing a bleeding point and the ability of angiographic haemostatic methods to control bleeding. METHODS: The case notes of a consecutive series of nine patients undergoing urgent SMA during 1996-1998 were analysed. Examination of angiography suite records confirmed the accuracy of patient identification. SMA was performed 18 times with 13 embolizations in nine individuals (seven men; median age 54 (27-73) years). Patients underwent the following operations: Whipple pancreaticoduodenectomy (four patients), pancreatic necrosectomy (two), total gastrectomy (one), cholecystectomy (one) and splenectomy (one). The median interval from surgery to haemorrhage was 15 (2-49) days. Six patients presented with haematemesis/melaena and three with bleeding from drains. Seven had evidence of shock (systolic blood pressure less than 100 mmHg, pulse more than 100 per min); the mean preprocedure haemoglobin concentration was 59 g/l. A median of 8 (4-14) units of blood were transfused before embolization and 4 (2-9) units after. Ten initial endoscopies were performed in six patients, seven of which revealed a source of bleeding. Endoscopic haemostasis was attempted in five and achieved temporary control of bleeding in two. RESULTS: Angiography revealed a discrete bleeding point in 13 of 18 procedures in eight patients. Where a bleeding point was identified, angiographic embolization using 3-8-mm stainless steel coils (ten) or a combination of coils and gelatin sponge (three) achieved radiological evidence of haemostasis in all cases. Periprocedural complications occurred in one patient with unintentional partial embolization of the right hepatic artery during embolization of an actively bleeding left hepatic artery pseudoaneurysm. Rebleeding occurred in six patients within 48 h. Three rebleeds were successfully managed with repeat SMA and embolization (one patient required a third embolization); the remaining three required surgery. Definitive radiological haemostasis was achieved in six patients. Five of the nine patients died in hospital, two of whom had been successfully embolized. CONCLUSIONS: In this group of patients, endoscopy contributed relatively little to treatment of postoperative haemorrhage. In contrast, SMA identified a bleeding point in eight of nine patients and achieved definitive control of bleeding in six. SMA and embolization appears to have a useful role in patients with this infrequent but potentially lethal complication.

Dietary practices and use of the ketogenic diet in the UK

With the introduction of Internet communications, parental interest has increased in the use of the ketogenic diet for epilepsy. It was decided to audit current practice in the use of the ketogenic diet in the UK. All paediatric dietitians who were members of the Paediatric Group of the British Dietetic Association were surveyed by a postal questionnaire. There was a 51% response rate. Twenty-two hospitals (17%) used the ketogenic diet with 101 patients being treated. Fifty-nine percent used the traditional 4:1 (four parts fat : one part carbohydrate, one part protein) classical ketogenic diet and 41% used the medium chain triglyceride diet (60% MCT fat). The age of patients ranged from 1 to over 11 years. There were wide variations in its application, with 66% of hospitals initiating the diet in hospital and 33% at home. The dietary energy administered varied from 60 to 90 kcal/kg/day, and there was no consistent policy on vitamin and mineral supplementation. Twenty-five patients continued to follow the diet after 12 months. Therefore, the ketogenic diet is commonly used for the treatment of intractable epilepsy in the UK. Further research work is needed on its nutritional safety and application.

A cluster of cases of legionnaires' disease associated with exposure to a spa pool on display

Interviews with four apparently sporadic cases of legionnaires' disease identified by laboratory reporting in one health district revealed that three of the four cases had been exposed to a new design of spa pool on display at a retail outlet. The fourth case had been exposed to the same design of spa pool in a private home. None had bathed in the spa pool. Legionella pneumophila serogroup 1 mAB subgroup 'Philadelphia' was isolated from samples taken from both spa pools. The display pool had not been maintained as recommended for a public spa pool in use by bathers. Revised maintenance instructions were issued to all purchasers of these spa pools in the United Kingdom (UK) and overseas. Patients may not remember specific exposures; scrutiny of activity diaries helped to identify exposure to a common location. Even when not in use by bathers, spa pools on display can be a source of legionella infection and should be maintained according to current hygiene guidelines.

Beta 1-, beta 2- and atypical beta-adrenoceptor-mediated relaxation in rat isolated aorta

beta-adrenoceptor-mediated relaxation was investigated in ring preparations of rat isolated thoracic aorta. Rings were pre-constricted with a sub-maximal concentration of noradrenaline (1 microM) and relaxant responses to cumulative concentrations of beta-adrenoceptor agonists obtained. The concentration-response curve (CRC) to isoprenaline was shifted to the right by propranolol (0.3 microM) with a steepening of the slope. Estimation of the magnitude of the shift from EC(50) values gave a pA(2) of 7.6. Selective beta(1)- and beta(2)-adrenoceptor antagonists, CGP 20712A (0.1 microM) and ICI 118551 (0.1 microM), respectively, produced 4 and 14 fold shifts of the isoprenaline CRC. Atypical beta-adrenoceptor agonists also produced concentration-dependent relaxation of aortic rings. The order of potency of the beta-adrenoceptor agonists was (-log EC(50)): isoprenaline (6. 25)>cyanopindolol (5.59)>isoprenaline+propranolol (5.11)>CGP 12177A (4.40)>ZD 2079 (4.24)>ZM 215001 (4.07)>BRL 37344 (3.89). Relaxation to CGP 12177A and ZM 215001 was unaffected by propranolol (0.3 microM). SR 59230A ( Collapse

Key Words

• atypical β-adrenoceptors
• β₃-adrenoceptors
• β₄-adrenoceptors
• β₁-adrenoceptors
• β₂-adrenoceptors
• vascular smooth muscle
• rat aorta

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MESH Headings

• Acetylcholine/pharmacology
• Adrenergic alpha-Agonists/pharmacology
• Adrenergic beta-Agonists/pharmacology
• Adrenergic beta-Antagonists/pharmacology
• Animals
• Aorta, Thoracic/drug effects
• Aorta, Thoracic/physiology
• Bupranolol/pharmacology
• Dose-Response Relationship, Drug
• Imidazoles/pharmacology
• In Vitro Techniques
• Isoproterenol/pharmacology
• Male
• Muscle Relaxation/drug effects
• Muscle Relaxation/physiology
• Muscle, Smooth, Vascular/drug effects
• Muscle, Smooth, Vascular/physiology
• Norepinephrine/pharmacology
• Pindolol/analogs & derivatives
• Pindolol/pharmacology
• Propanolamines/pharmacology
• Propranolol/pharmacology
• Rats
• Rats, Wistar
• Receptors, Adrenergic, beta/classification
• Receptors, Adrenergic, beta/physiology
• Receptors, Adrenergic, beta-1/physiology
• Receptors, Adrenergic, beta-2/physiology
• Substrate Specificity
• Vasodilator Agents/pharmacology

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Grants Collapse

Poly(ADP-ribose) polymerase at active centromeres and neocentromeres at metaphase

A double-stranded 9 bp GTGAAAAAG pJ alpha sequence found in human centromeric alpha-satellite DNA and a 28 bp ATGTATATATGTGTATATAGACATAAAT tandemly repeated AT28 sequence found within a cloned neo- centromere DNA have each allowed the affinity purification of a nuclear protein that we have identified as poly(ADP-ribose) polymerase (PARP). Use of other related or unrelated oligonucleotide sequences as affinity substrates has indicated either significantly reduced or no detectable PARP purification, suggesting preferential but not absolute sequence-specific binding. Immunofluorescence analysis of human and sheep metaphase cells using a polyclonal anti-PARP antibody revealed centromeric localization of PARP, with diffuse signals also seen on the chromosome arms. Similar results were observed for mouse chromosomes except for a significantly enlarged PARP-binding region around the core centromere-active domain, suggesting possible 'spreading' of PARP into surrounding non-core centromeric domains. Enhanced PARP signals were also observed on alpha-satellite-negative human neo- centromeres and on the active but not the inactive alpha-satellite-containing centromere of a human dicentric chromosome. PARP signals were absent from the q12 heterochromatin of the Y chromosome, suggesting a correlation of PARP binding with centromere function that is independent of heterochromatic properties. Preliminary cell cycle analysis indicates detectable centromeric association of PARP during S/G(2)phase and that the total proportion of PARP that is centromeric is relatively low. Strong binding of PARP to different centromere sequence motifs may offer a versatile mechanism of mammalian centromere recognition that is independent of primary DNA sequences.

5-hydroxytryptamine- and U46619-mediated vasoconstriction in bovine pulmonary conventional and supernumerary arteries: effect of endogenous nitric oxide

We compared 5-hydroxytryptamine (5-HT)- and U46619-mediated contractions in bovine pulmonary conventional arteries (CA) and supernumerary arteries (SA). The effects of the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) (100 microM) and the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4, 3-a]quinoxalin-1-one (ODQ) (10 microM) on the responses of CA and SA to 5-HT and U46619 were also examined. In addition, the effects of the 5-HT(2B) receptor antagonist SB 200646 (1 nM-1 microM) on the responses to 5-HT in SA and CA were studied. Tissue cGMP levels were measured in the absence and presence of L-NAME, ODQ, 5-HT and U46619. 5-HT was approximately 30 times more potent in SA ¿-log[EC(50) (M)] (pEC(50)) 6.32+/-0.13¿ than in CA (5.05+/-0.14). U46619 displayed a similar potency in both CA (pEC(50) 7.80+/-0.07) and SA (7.75+/-0. 12). L-NAME did not significantly alter the resting tone of CA or SA. In contrast, ODQ produced a transient increase in the tone of both CA and SA. Neither L-NAME nor ODQ altered the responses to 5-HT or U46619 in CA. In addition, neither L-NAME nor ODQ altered the responses to U46619 in SA, but both L-NAME and ODQ increased the magnitude of the response to 5-HT in SA without changing the sensitivity. Inhibition of the 5-HT(2B) receptor with SB 200646 did not alter the response to 5-HT in SA or CA. Basal levels of cGMP (pmol/mg of protein) were similar in CA (1.16+/-0.33) and SA (0. 8+/-0.51), and were not significantly changed in the presence of 5-HT or U46619. L-NAME and ODQ reduced the basal levels of cGMP in both SA and CA. The results suggest that endogenous NO selectively attenuates the vasoconstrictor response to 5-HT in SA, but not in CA. These results also suggest that the NO/cGMP pathway may have a role in maintaining low vascular tone, but that other mechanisms are able to compensate for the absence of this pathway.

V-shaped cushion at the origin of bovine pulmonary supernumerary arteries: structure and putative function

This study investigates the anatomic structure at the origin of pulmonary supernumerary arteries and their parent conventional artery. Histological examination showed that at the origin of each supernumerary artery the wall of the parent conventional artery is organized into a distinct V-shaped structure, which begins on the hilum side of each supernumerary artery as a funnel-shaped channel running into the supernumerary artery. The base of the channel is particularly thin walled. The lateral walls of the channel are composed of musculoelastic cushions that become more pronounced toward the supernumerary artery and fuse on its distal side, forming a baffle that projects over the supernumerary artery lumen. These V-shaped structures/cushions were observed with video stereo dissecting microscopy in both an open and closed state in isolated arteries in vitro. Pulmonary vasoconstriction of isolated arteries with the thromboxane A(2) mimetic U-46619 increased the number of V-shaped structures in the closed state. These studies indicate the presence of a novel anatomic structure at the origin of pulmonary supernumerary arteries, which may be able to regulate blood flow into the supernumerary artery.

Identification of patients to include in trauma audit: a modification of the pre-chart

Trauma audit is commonly focused using a Pre-Chart to illustrate calculations made using the TRISS model. A line is drawn at Ps = 0.5 to divide expected survivors and nonsurvivors. The use of this cut-off in a severely injured population was examined. The 'M statistic' for a group of injured patients selectively triaged to a Trauma Centre was calculated. The ideal cut-off point between predicted outcomes when using the TRISS model to focus trauma audit in this population was determined using a Receiver Operating Characteristic (ROC) curve. For this population the TRISS 'M statistic' was 0.71 (indicating a significantly different case mix from the reference database) and the best cut-off point was at Ps = 0.76. Trauma audit in populations with a case mix of injury severity different from the reference database should use a different Ps line to define unexpected outcomes.

Psychological characteristics of people with perceived food intolerance in a community sample

In most adults who believe themselves to be food intolerant there is no objective supporting evidence. It has therefore been proposed that the misperception of intolerance to food is linked to psychiatric illness or personality disorder. This hypothesis was tested in a community-derived sample of individuals who attributed an adverse symptom to a type of food. A random mailing recruited 955 participants aged > or =18 years, of whom 232 perceived themselves to be food intolerant (PFI). All recruits were sent two questionnaires, the General Health Questionnaire-28 (GHQ-28) and the shortened version of the Eysenck Personality Questionnaire (EPQ-R). A total of 535 GHQ-28 and 518 EPQ-R forms were returned that were correctly completed, an overall response rate of 55%. For the subscales of the EPQ-R, neuroticism was greater in those with a PFI than those without. Women with a PFI were more extroverted than control women. For the GHQ-28 subscales, women with a PFI had significantly higher scores than control women on somatic symptoms, anxiety, insomnia, and severe depression. There was a greater percentage of psychiatric caseness among women with a PFI than among men with a PFI or control women. Nevertheless, this percentage was no greater than that reported among a reference sample derived from NHS and university staff. It is concluded that perceived food intolerance is associated with psychological distress in women with a PFI, and neurotic symptoms in both men and women with a PFI, but there is no greater prevalence of psychiatric disorder among women or men with a PFI than there is in some professional groups.

Effects of propranolol and L-NAME on beta-adrenoceptor-mediated relaxation in rat carotid artery

1. The properties of beta-adrenoceptors mediating vascular relaxation in rat isolated carotid artery were investigated. Ring segments of arteries were preconstricted with the thromboxane A2 receptor agonist U-46619 and relaxation to beta-adrenoceptor agonists determined. 2. Isoprenaline produced a concentration-dependent relaxation of U-44619-constricted arteries. The concentration-response curve (CRC) to isoprenaline was shifted to the right by propranolol (1 microM) although the shift was less (105 fold; pA2, 8.02) than would be expected for an effect of isoprenaline at classical beta-adrenoceptors (300-1000 fold; pA2, 8.5-9). L-NAME (100 microM) significantly reduced responses to isoprenaline, lowering the slope of the CRC and reducing the maximum response. 3. The selective beta3-adrenoceptor agonists, BRL 37344 and ZD2079, also produced concentration-dependent relaxation of the arteries. L-NAME (100 microM) shifted the BRL 37344 CRC to the right 15 fold with no reduction in the slope or maximum response. L-NAME (100 microM) had no significant effect on the ZD2079 CRC. 4. In conclusion, relaxation to isoprenaline in rat carotid artery is inhibited by propranolol in a manner suggesting a mixed population of classical (beta1-/beta2-) and atypical (beta3-) adrenoceptors. The presence of beta3-adrenoceptors was confirmed by the relaxant effects of the selective beta3-adrenoceptor agonists BRL 37344 and ZD2079. L-NAME attenuated responses to both isoprenaline and the beta3-adrenoceptor agonist BRL 37344, suggesting a role for endothelial release of nitric oxide in beta-adrenoceptor mediated relaxation. However, the relaxant effect of BRL 37344 was attenuated by L-NAME to a lesser extent than that of isoprenaline. In addition, L-NAME had no effect on relaxation induced by ZD2079. These results suggest that there may be a differential contribution of endothelium to classical beta-and beta3-adrenoceptor-mediated effects, with endothelium contributing less to beta3-adrenoceptor-mediated relaxation.

Characterisation of the atypical beta-adrenoceptor in rabbit isolated jejunum using BRL 37344, cyanopindolol and SR 59230A

The present study was carried out to further investigate the nature of the beta-adrenoceptor in rabbit jejunum using BRL 37344, a selective beta3-adrenoceptor agonist, cyanopindolol, a beta-adrenoceptor antagonist with blocking activity at beta3-adrenoceptors and SR 59230A, a new selective beta3-adrenoceptor antagonist. Isoprenaline produced a concentration-dependent inhibition of the spontaneous contractions of rabbit jejunum with a pD2 of 7.14. Propranolol (1 microM) shifted the isoprenaline concentration-response curve (CRC) to the right with a concentration-ratio of 5.85, considerably less than would be expected for an action at classical beta-adrenoceptors (estimated pA2 6.66). BRL 37344 also produced a concentration-dependent inhibition of spontaneous contractions with a pD2 of 7.41. The BRL 37344 CRC was unaffected by propranolol (1 microM). In the presence of propranolol (1 microM), cyanopindolol (1 microM) shifted the isoprenaline CRC to the right (concentration-ratio of 21). Cyanopindolol also shifted the BRL 37344 CRC to the right (concentration-ratio of 38). These shifts are consistent with the affinity of cyanopindolol for beta3-adrenoceptors (estimated pA2 values of 7.27 and 7.38 against isoprenaline and BRL 37344, respectively). In the presence of propranolol (1 microM), SR 59230A produced a concentration-dependent rightward shift of the isoprenaline CRC. The Schild plot gave a pA2 value of 7.16, although the slope of the regression line was significantly different from unity (0.65). SR 59230A also produced a concentration-dependent shift of the BRL 37344 CRC. The Schild plot gave a pA2 of 7.58 with the slope of the regression line not significantly different from unity (0.81). The presence of beta3-adrenoceptors mediating relaxation of spontaneous contractions in rabbit jejunum is supported by the relatively poor antagonism of isoprenaline by propranolol, the relaxant effect of BRL 37344 and the antagonism of isoprenaline and BRL 37344 by cyanopindolol and SR 59230A. The lack of simple competitive antagonism of isoprenaline, but not BRL 37344, by SR 59230A may suggest more than one population of atypical beta-adrenoceptor.

Iron supplemented formula milk related to reduction in psychomotor decline in infants from inner city areas: randomised study

OBJECTIVE

To compare the effect of unmodified cows' milk and iron supplemented formula milk on psychomotor development in infants from inner city areas when used as the main milk source.

DESIGN

Double blind, randomised intervention trial.

SETTING

Birmingham health centre.

SUBJECTS

100 infants, mean age 7.8 months (range 5.7 to 8.6 months), whose mothers had already elected to use unmodified cows' milk as their infant's milk source.

INTERVENTION

Changing to an iron supplemented formula milk from enrolment to 18 months of age, or continuing with unmodified cows' milk.

MAIN OUTCOME MEASURES

Developmental assessments using Griffiths scales at enrolment and at 18 and 24 months.

RESULTS

85 participants completed the trial. There were no significant differences in haemoglobin concentration between the two groups at enrolment, but by 18 months of age 33% of the unmodified cows' milk group, but only 2% of the iron supplemented group, were anaemic (P<0.001). The experimental groups had Griffiths general quotient scores that were not significantly different at enrolment, but the scores in both groups declined during the study. By 24 months the decrease in the mean scores in the unmodified cows' milk group was 14.7 whereas the decrease in the mean scores in the iron supplemented group was 9.3 (P<0.02, 95% confidence interval 0.4 to 10.4). Mean subquotient scores were considerably lower in the unmodified cows' milk group at 24 months; significantly so for personal and social scores (P<0.02, 1.2 to 16.8 [corrected]).

CONCLUSION

Replacing unmodified cows' milk with an iron supplemented formula milk up to 18 months of age in infants from inner city areas prevents iron deficiency anaemia and reduces the decline in psychomotor development seen in such infants from the second half of the first year.