In vivo coronary artery thrombus imaging with 18F-GP1 PET-CT

Background

Coronary artery thrombus is typically present in type 1 myocardial infarction, but small volumes in the setting of an uncertain culprit lesion may be beyond the detection limit of current imaging modalities.

Purpose

Using a novel glycoprotein IIb/IIIa-receptor radiotracer, 18F-GP1, we investigated whether positron emission tomography-computed tomography (PET-CT) could detect thrombus formation in coronary arteries.

Methods

In a single centre cross-sectional study, patients over 40 years of age with myocardial infarction were recruited after myocardial infarction and underwent underwent CT angiography and 18F-GP1 PET-CT. Stable patients with and without coronary artery disease formed a control cohort. Coronary artery 18F-GP1 uptake was visually assessed and quantified using maximum target-to-background ratios (TBRmax).

Results

Ninety-four (44 post-myocardial infarction and 50 control patients) were included in the cross-sectional analysis. The mean age of the post-myocardial infarction group was 61±9 years, three-quarters were male and two thirds had presented with ST elevation on electrocardiography. 34 (80%) patients post-myocardial infarction, but none of the control patients, demonstrated focal 18F-GP1 uptake in the coronary arteries.

Of 42 vessels with an angiographic culprit lesion, 35 (83%) had 18F-GP1 uptake which was significantly higher than non-culprit vessels (p<0.0001) as well as control vessels (p<0.0001), while non-culprit vessel uptake was similar to control vessel uptake (p=0.567): culprit vessel median TBRmax 1.2 [interquartile range 0.96–1.44], non-culprit vessel TBRmax 0.96 [0.84–1.03] and control vessel TBRmax 0.9 [0.76 to 0.94]. Linear regression models demonstrated univariable associations between coronary 18F-GP1 TBRmax and time from myocardial infarction, male sex and presence of culprit vessel. On multivariable analysis, only culprit vessel status was associated with TBRmax (adjusted R2= 0.22, P<0.001). Based on the Youden's index of the ROC curves, the optimal cut-off of predicting the presence of a culprit vessel was 1.20 with a specificity of 97%, accuracy of 83%, sensitivity (60%) and c-statictic of 0.74.

A patient with ectatic vessel and visual thrombus demonstrated the most intense 18F-GP1 uptake (TBRmax 2.0, highest in the cohort) in the region of heaviest thrombus burden (Figure 2). Extra-coronary uptake was seen in regions of left ventricular thrombus, left atrial appendage thrombus, pulmonary thromboembolism and intramyocardial microvascular obstruction.

Conclusions

18F-GP1 PET-CT is able to detect coronary artery thrombus in culprit lesions following myocardial infarction, as well as extra-coronary thrombotic pathologies that may be important in guiding patient management. 18F-GP1 is highly specific in recognising a culprit lesion from a non-culprit lesion both visually as well as quantitatively.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Figure 1Figure 2

130 Boerhaave’s Syndrome: A Rare Complication of Cannabinoid-Induced Hyperemesis Syndrome

A 22-year-old man was referred to our surgical department with severe central chest pain after a three-day history of > 200 episodes of vomiting a day on a known background of cannabinoid hyperemesis syndrome. A computed tomography (CT) scan showed a ruptured oesophagus and pneumomediastinum, in keeping with Boerhaave’s syndrome. Conservative treatment with keeping the patient nil by mouth and administering intravenous fluids, anti-emetics and broad-spectrum antibiotics was initiated. Follow up CT showed significant reduction in pneumomediastinum. The patient was discharged home 7 days after admission. Spontaneous rupture of the oesophagus is a rare but potentially fatal event. It is caused by an abrupt rise in intra-luminal pressure, usually secondary to forceful vomiting. CT scan should be performed in all suspected cases as the findings dictate management, this being conservative, endoscopic, or surgical. We report on the first published case of Boerhaave’s syndrome as a result of cannabinoid hyperemesis syndrome.

A randomised controlled trial of energetic activity for depression in young people (READY): a multi-site feasibility trial protocol

BACKGROUND

Prevalence of depression is increasing in young people, and there is a need to develop and evaluate behavioural interventions which may provide benefits equal to or greater than talking therapies or pharmacological alternatives. Exercise could be beneficial for young people living with depression, but robust, large-scale trials of effectiveness and the impact of exercise intensity are lacking. This study aims to test whether a randomised controlled trial (RCT) of an intervention targeting young people living with depression is feasible by determining whether it is possible to recruit and retain young people, develop and deliver the intervention as planned, and evaluate training and delivery.

METHODS

The design is a three-arm cluster randomised controlled feasibility trial with embedded process evaluation. Participants will be help-seeking young people, aged 13-17 years experiencing mild to moderate low mood or depression, referred from three counties in England. The intervention will be delivered by registered exercise professionals, supported by mental health support workers, twice a week for 12 weeks. The three arms will be high-intensity exercise, low-intensity exercise, and a social activity control. All arms will receive a 'healthy living' behaviour change session prior to each exercise session and the two exercise groups are energy matched. The outcomes are referral, recruitment, and retention rates; attendance at exercise sessions; adherence to and ability to reach intensity during exercise sessions; proportions of missing data; adverse events, all measured at baseline, 3, and 6 months; resource use; and reach and representativeness.

DISCUSSION

UK National Health Service (NHS) policy is to provide young people with advice about using exercise to help depression but there is no evidence-based exercise intervention to either complement or as an alternative to medication or talking therapies. UK National Institute for Health and Care Excellence (NICE) guidelines suggest that exercise can be an effective treatment, but the evidence base is relatively weak. This feasibility trial will provide evidence about whether it is feasible to recruit and retain young people to a full RCT to assess the effectiveness and cost-effectiveness of an exercise intervention for depression.

TRIAL REGISTRATION

ISRCTN, ISRCTN66452702 . Registered 9 April 2020.

The Hidradenitis Suppurativa Priority Setting Partnership

BACKGROUND

Hidradenitis suppurativa (HS) has been neglected by medical researchers and society in general, despite being a relatively common, painful, chronic skin disease.

OBJECTIVES

To generate a top 10 list of HS research priorities, from the perspectives of patients with HS, carers and clinicians, to take to funding bodies.

METHODS

A priority setting partnership was established between patients with HS, carers and clinicians, following the James Lind Alliance process. Survey 1 requested submission of HS uncertainties, which were grouped into 'indicative uncertainties' for prioritization in survey 2. The 30 highest-ranked indicative uncertainties were reduced to a 'top 10' list using nominal group technique at a prioritization workshop attended by all relevant HS stakeholders.

RESULTS

In total 1495 potential uncertainties were submitted in survey 1, including 57% from patients with HS and carers, and grouped into 55 indicative uncertainties. Ranking in survey 2 was completed by 371 participants, 50% of whom were patients and carers. The final workshop was attended by 22 HS stakeholders and four facilitators and produced a top 10 list, the three highest priorities in descending order being (i) What is the most effective and safe group of oral treatments in treating HS? (ii) What is the best management of an acute flare? (iii)What is the impact of HS and its treatment on people with HS?

CONCLUSIONS

The top 10 HS research priorities have been directly disseminated to funders to raise awareness of HS. The next step is to generate research questions that will provide the evidence needed to improve care for patients with HS.

Realizing nursing: a multimodal biopsychopharmacosocial approach to psychiatric nursing

The biological and psychosocial components of health, illness and treatment are well recognized. In addition, pharmacological interventions interact with both these components regarding health and illness; all components are potentially modifiable. A better understanding of these interactions on the course of illness, especially at the interface between illness and treatment, is needed to guide effective clinical and psychiatric nursing interventions. To this end, a multimodal biopsychopharmacosocial approach to assessment, formulation, care planning and implementation by psychiatric nurses is proposed. It is argued that a biopsychopharmacosocial approach, including a multimodal functional element, provides a person-centred, responsive and responsible basis for a comprehensive approach to practice. The use of this approach will improve intervention outcomes and contribute to the ongoing development of psychiatric nursing practice. It is suggested that, in part, this will be achieved through innovative teaching methods delivered by 'expert nurses' and clinical academics.

Evidence for linkage of migraine in Rolandic epilepsy to known 1q23 FHM2 and novel 17q22 genetic loci

Migraine headaches are a common comorbidity in Rolandic epilepsy (RE) and familial aggregation of migraine in RE families suggests a genetic basis not mediated by seizures. We performed a genome-wide linkage analysis of the migraine phenotype in 38 families with RE to localize potential genetic contribution, with a follow-up in an additional 21 families at linked loci. We used two-point and multipoint LOD (logarithm of the odds) score methods for linkage, maximized over genetic models. We found evidence of linkage to migraine at chromosome 17q12-22 [multipoint HLOD (heterogeneity LOD) 4.40, recessive, 99% penetrance], replicated in the second dataset (HLOD 2.61), and suggestive evidence at 1q23.1-23.2, centering over the FHM2 locus (two-point LOD 3.00 and MP HLOD 2.52). Sanger sequencing in 14 migraine-affected individuals found no coding mutations in the FHM2 gene ATP1A2. There was no evidence of pleiotropy for migraine and either reading or speech disorder, or the electroencephalographic endophenotype of RE when the affected definition was redefined as those with migraine or the comorbid phenotype, and pedigrees were reanalyzed for linkage. In summary, we report a novel migraine susceptibility locus at 17q12-22, and a second locus that may contribute to migraine in the general population at 1q23.1-23.2. Comorbid migraine in RE appears genetically influenced, but we did not obtain evidence that the identified susceptibility loci are consistent with pleiotropic effects on other comorbidities in RE. Loci identified here should be fine-mapped in individuals from RE families with migraine, and prioritized for analysis in other types of epilepsy-associated migraine.

Can lower risk patients presenting with transient ischaemic attack be safely managed as outpatients?

This study aimed to examine outcome in low risk transient ischaemic attack (TIA) patients presenting to emergency departments (ED) in a regional Australian setting discharged on antiplatelet therapy with expedited neurology review. All patients presenting to Gosford or Wyong Hospital ED with TIA, for whom faxed referrals to the neurology department were received between October 2008 and July 2010, were included in this prospective cohort study. Classification of low risk was based on an age, blood pressure, clinical features, duration of symptoms and diabetes (ABCD2) score <4 and the absence of high risk features, including known carotid disease, crescendo TIA, or atrial fibrillation. Patients with ABCD2 scores > or =4 or with high risk features were discussed with the neurologist on call (a decision regarding discharge or admission was then made at the neurologist's discretion). Patients were investigated with a brain CT scan and/or CT angiography, routine pathology, and an electrocardiogram. All discharged patients were commenced on antiplatelet therapy and asked to follow up with their local medical officer within 7 days. The patients were contacted by the neurology department to arrange follow-up. Our primary outcome was the number of subsequent strokes occurring within 90 days. Of 200 discharged patients for whom referrals were received, three patients had a stroke within 90 days. None of these would have been prevented through hospitalisation. In conclusion, medical assessment, expedited investigation with immediate commencement of secondary prevention and outpatient neurology review may be a reasonable alternative to admission for low risk patients presenting to the ED with TIA.

SU-D-BRCD-06: Measurement of Elekta Electron Energy Spectra Using a Small Magnetic Spectrometer

PURPOSE

To demonstrate how a small magnetic spectrometer can measure the energy spectra of seven electron beams on an Elekta Infinity tuned to match beams on a previously commissioned machine.

METHODS

Energyspectra were determined from measurements of intensity profiles on 6″-long computed radiographic (CR) strips after deflecting a narrow incident beam using a small (28 lbs.), permanent magnetic spectrometer. CR plateexposures (<1cGy) required special beam reduction techniques and bremsstrahlung shielding. Curves of CR intensity (corrected for non- linearity and background) versus position were transformed into energy spectra using the transformation from position (x) on the CR plate to energy (E) based on the Lorentz force law. The effective magnetic field and its effective edge, parameters in the transformation, were obtained by fitting a plot of most probable incident energy (determined from practical range) to the peak position.

RESULTS

The calibration curve (E vs. x) fit gave 0.423 Tesla for the effective magnetic field. Most resulting energy spectra were characterized by a single, asymmetric peak with peak position and FWHM increasing monotonically with beam energy. Only the 9-MeV spectrum was atypical, possibly indicating suboptimal beam tuning. These results compared well with energy spectra independently determined by adjusting each spectrum until the EGSnrc Monte Carlo calculated percent depth-dose curve agreed well with the corresponding measured curve.

CONCLUSIONS

Results indicate that this spectrometer and methodology could be useful for measuring energy spectra of clinical electron beams at isocenter. Future work will (1) remove the small effect of the detector response function (due to pinhole size and incident angular spread) from the energy spectra, (2) extract the energy spectra exiting the accelerator from current results, (3) use the spectrometer to compare energy spectra of matched beams among our clinical sites, and (4) modify the spectrometer to utilize radiochromic film.

In vitro and in vivo characterization of PF-04418948, a novel, potent and selective prostaglandin EP₂ receptor antagonist

BACKGROUND AND PURPOSE

Studies of the role of the prostaglandin EP(2) receptor) have been limited by the availability of potent and selective antagonist tools. Here we describe the in vitro/in vivo pharmacological characterization of a novel EP(2) receptor antagonist, PF-04418948 (1-(4-fluorobenzoyl)-3-{[(6-methoxy-2-naphthyl)oxy]methyl} azetidine-3-carboxylic acid).

EXPERIMENTAL APPROACH

Functional antagonist potency was assessed in cell-based systems expressing human EP(2) receptors and native tissue preparations from human, dog and mouse. The selectivity of PF-04418948 was assessed against related receptors and a panel of GPCRs, ion channels and enzymes. The ability of PF-04418948 to pharmacologically block EP(2) receptor function in vivo was tested in rats.

KEY RESULTS

PF-04418948 inhibited prostaglandin E(2)(PGE(2))-induced increase in cAMP in cells expressing EP(2) receptors with a functional K(B) value of 1.8 nM. In human myometrium, PF-04418948 produced a parallel, rightward shift of the butaprost-induced inhibition of the contractions induced by electrical field stimulation with an apparent K(B) of 5.4 nM. In dog bronchiole and mouse trachea, PF-04418948 produced parallel rightward shifts of the PGE(2)-induced relaxation curve with a K(B) of 2.5 nM and an apparent K(B) of 1.3 nM respectively. Reversal of the PGE(2)-induced relaxation in the mouse trachea by PF-04418948 produced an IC(50) value of 2.7 nM. Given orally, PF-04418948 attenuated the butaprost-induced cutaneous blood flow response in rats. PF-04418948 was selective for EP(2) receptors over homologous and unrelated receptors, enzymes and channels.

CONCLUSIONS AND IMPLICATIONS

PF-04418948 is an orally active, potent and selective surmountable EP(2) receptor antagonist that should aid further elaboration of EP(2) receptor function.

Guerrillero Heroico--a lasting impression

What once was simply a cultural tradition is fast becoming a popular phenomenon amongst Western tourists. Temporary henna tattoo designs performed by street or beach vendors are prevalent throughout the Middle East and Asia, particularly in holiday resorts. The public may be mistaken in thinking that the fashionable trend comes without significant risk. The main ingredient in the temporary tattooing method is henna (Lawsonia inermis), a flowering plant with dyeing properties that takes only several hours to be absorbed but provides an effect lasting around ten to fifteen days on the recipient's skin. The side effects of henna tattoos are well documented in the literature, although it is not clear whether the side effects directly relate to the henna ingredient or the additives used to prolong the designs. The most commonly noted complications include allergic contact dermatitis, infection, hypertrophic and keloid scarring and temporary or permanent hypo- or hyperpigmentation. In very rare cases, type 1 hypersensitivity reactions (angioedema and anaphylaxis) have been reported. The following case report highlights several of these complications and the relevant management.

Supplementation with whole cottonseed causes long-term reduction of methane emissions from lactating dairy cows offered a forage and cereal grain diet

The objective of our work was to supplement a forage and cereal diet of lactating dairy cows with whole cottonseed (WCS) for 12 wk and to determine whether the expected reduction in CH(4) would persist. A secondary objective was to determine the effect of supplementing the diet with WCS on milk yield and rumen function over the 12-wk feeding period. Fifty lactating cows were randomly allocated to 1 of 2 diets (control or WCS). The 2 separate groups were each offered, on average, 4.2 kg of DM/cow per day of alfalfa hay (a.m.) and 6.6 kg of DM/cow per day of ryegrass silage (p.m.) on the ground in bare paddocks each day for 12 wk. Cows in each group were also individually offered dietary supplements for 12 wk in a feed trough at milking times of 5.4 kg of DM/cow per day of cracked wheat grain and 0.5 kg of DM/cow per day of cottonseed meal (control) or 2.8 kg of DM/cow per day of cracked wheat grain and 2.61 kg of DM/cow per day of WCS. The 2 diets were formulated to be similar in their concentrations of CP and ME, but the WCS diet was designed to have a higher fat concentration. Samples of rumen fluid were collected per fistula from the rumen approximately 4 h after grain feeding in the morning. Samples were taken from 8 cows (4 cows/diet) on 2 consecutive days in wk 2 of the covariate and wk 3, 6, 10, and 12 of treatment and analyzed for volatile fatty acids, ammonia-N, methanogens, and protozoa. The reduction in CH(4) emissions (g/d) because of WCS supplementation increased from 13% in wk 3 to 23% in wk 12 of treatment. Similarly, the reduction in CH(4) emissions (g/kg of DMI) increased from 5.1% in wk 3 to 14.5% in wk 12 of treatment. It was calculated that the average reduction in CH(4) emissions over the 12-wk period was 2.9% less CH(4) per 1% added fat, increasing from 1.5% in wk 3 to 4.4% less CH(4) in wk 12. There was no effect of WCS supplementation on rumen ammonia-N, rumen volatile fatty acids, rumen methanogens, and rumen protozoa. On average over the 12-wk period, supplementation with WCS decreased the yield of milk (10%), fat (11%), protein (14%), lactose (11%), and fat plus protein (12%) and BW gain (31%). The WCS supplementation had no effect on milk fat concentration but resulted in a decrease in concentration of protein (5%) and lactose (11%). The major finding from this study is that addition of WCS to the diet of lactating dairy cows resulted in a persistent reduction in CH(4) emissions (g of CH(4)/kg of DMI) over a 12-wk period and that these reductions in CH(4) are consistent with previous work that has studied the addition of oilseeds to ruminant diets.

imProving Outcomes after STroke clinical pilot trial protocol

RATIONALE

One in three patients experience depression after stroke and this risk is consistent over time. A strategy to prevent depression that could be economically delivered to most stroke patients and ideally which also has a low likelihood of adverse events needs to be developed and evaluated. Aims POST aims to determine whether a simple intervention (postcards) prevents depression (Hospital Anxiety and Depression rating Scale, HADS depression subscale score > or =8) in patients with a recent stroke. Secondary end-points include reduced anxiety (HADS anxiety subscale score > or =8) and improved health-related quality of life in patients with a recent stroke.

DESIGN

A single-centre randomised, double-blind, pilot trial to prevent depression in patients with a recent (within 8 weeks) stroke presenting to hospital. Patients will be enrolled over 12 months and randomised to receive three trial-specific assessments (baseline, 3- and 6-month assessments of mood, HRQoL and social functioning), or three trial-specific assessments plus a postcard sent centrally in a sealed envelope at 1, 2, 3, 4 and 5 months after discharge from hospital. Blinded follow-up telephone assessments will be conducted for both groups. STUDY OUTCOMES AND SAMPLE SIZE: For the primary end-point the POST trial will have 80% power to detect a relative risk of 0.4 given an incidence of depression of 30%. For the secondary aims POST has 90% power to detect a difference of 3 points on the HADS depression subscale (assuming a standard deviation of 6 points) between randomised groups. This includes an inflation factor of 15% to account for patients lost to follow-up.

DISCUSSION

Evidence of efficacy will determine whether a multi-centre, international trial is warranted.

Zoning: focused support: a trust wide implementation project

Applying pragmatic risk management procedures to facilitate the sharing of clinical knowledge in and across mental health teams. Abstract Zoning: focused support is pragmatic risk management support procedure that enhances adherence to operational policies, provides a forum in which staff can receive support and visually facilitates the sharing of clinical knowledge. This paper presents a 3-year multi-method management project that sought to introduce zoning principles into all teams of an inner city Mental Health NHS Trust. By changing the language and culture of the organization findings indicate that there has been a positive attitudinal shift in how the approach is perceived. It is considered to be of value to staff, service users and their families and 73% of teams are now using it routinely.

Severe hyperbilirubinaemia and kernicterus: more caution is needed in newborn jaundice surveillance

Since the 1990s, there has been a re-emergence of cases of severe hyperbilirubinaemia and kernicterus. The current UK incidence of bilirubin encephalopathy is 0.9/100,000 with a higher reported incidence in some countries. Three otherwise healthy newborn infants, who presented with severe hyperbilirubinaemia, including one who developed kernicterus, are reported here. Some of the current challenges in newborn jaundice surveillance are highlighted.

Potential use of Acacia mearnsii condensed tannins to reduce methane emissions and nitrogen excretion from grazing dairy cows

We measured the effect of condensed tannins (CT) extracted from the bark of the Black Wattle tree (Acacia mearnsii) on the milk production, methane emissions, nitrogen (N) balance and energy partitioning of lactating dairy cattle. Sixty lactating cows, approximately 32 d in milk grazing ryegrass pasture supplemented with 5 kg d-1 cracked triticale grain, were allocated to three treatments: Control, Tannin 1 (163 g CT d-1) or Tannin 2 (326 g CT d-1 initially, reduced to 244 g d-1 CT by day 17). Cows were dosed twice daily after milking for 5 wk with the powdered CT extract (mixed 1:1 with water). Low and high CT supplementation reduced (P < 0.05) methane emissions by 14 and 29%, respectively (about 10 and 22% on an estimated dry matter intake basis). However, milk production was also reduced by the CT (P < 0.05), especially at the high dose rate. Milk yields were 33.0, 31.8 and 29.8 kg cow-1 d-1. Tannin 2 also caused a 19% decline in fat yield and a 7% decline in protein yield, but protein and lactose contents of milk were not affected by CT supplementation. After the initial 5-wk period, five cows representative of each treatment group were moved to metabolism facilities to determine effects of CT on energy digestion and N balance over 6 d. The energy digestibility was reduced (P < 0.05) from 76.9 (Control) to 70.9 (Tannin 1) and 66.0% (Tannin 2) and the percentage of feed N lost to urine was reduced (P < 0.05) from 39 to 26% and 22% for the respective treatments. The CT also caused a reduction (P < 0.05) in intake during the metabolism study, effectively increasing CT as a percentage of intake. Although CT can be used to reduce methane and urinary N losses from cows fed pastures with a high crude protein (CP) concentration, reduced milk yield in this study suggested the dietary concentration was too high. If CT are to be considered as a means for lowering methane emissions further research is needed to define impacts of lower doses of A. mearnsii CT on methane production and cow productivity. Dairy producers will be reluctant to adopt feeding practices that compromise profitability.Key words: Dairy cow, condensed tannins, methane, milk production, energy, nitrogen balance

National neonatal weight policy survey

This survey was conducted to review the current practice regarding frequency of weight measurement in neonatal units in the Republic of Ireland, and whether these practices are in keeping with best practice as described in the literature. There was an 88.5% (23 of 26) response rate to this survey. 6 (26%) units had a written policy, and 16 (70%) had an unwritten agreed practice. In the Vermont Oxford Network's potentially better practices daily weight measurements on newborn infants are recommended until the infant is stable and growing and then alternate day measurements The most common practices in this survey were to weigh infants on alternate days, this occurred in 9 (39%) units, and twice weekly in 6 (26%). Less than 31% of units had a separate policy for those less than 30 weeks, on assisted ventilation, or transitioning to enteral feeds. Most weigh infants on alternate days, and plot weights weekly, which is in keeping with best practice. Few units have separate policies for specific subgroups as is recommended in the limited literature. Consensus guidelines should be developed and promoted nationally.

Irish neonatal mortality statistics for 2004 and over the past 17 years: how do we compare internationally?

In the past 17 years neonatal mortality survey has provided important data on the trends in deaths of all live born infants born in Southern Ireland who are greater than 500 g birth weight and who die within the first 28 days of life. The aims of this study were to report neonatal mortality data for Southern Ireland for 2004, to examine trends in neonatal mortality over the past 17 years and compare Irish Neonatal Mortality rates to other countries around the world. The neonatal mortality rate for 2004 was 2.9/1000 with a corrected NMR of 1.9/1000. The response rate to the survey was 100%. Prematurity is now the leading cause of neonatal mortality representing a change from previous years. Deaths related to asphyxia have remained largely unchanged. When compared to international figures Ireland compares favourably to other countries around the world.

A national survey of current practice in the management of very low and extremely low birth weight infants: is there a role for national guidelines?

Substantial variation exists in the use of a number of post natal interventions and procedures between neonatal intensive care units. This study examined current practice in the management of commonly encountered problems in very low and extremely low birth weight infants in the eight regional units in Ireland, and was intended to determine whether support exists for the development of national practice guidelines. Ninety one percent of people surveyed returned a completed questionnaire, 76% of respondents believed it would be both worthwhile and practical to develop national practice guidelines. We therefore recommend, that a working group for the establishment of national practice guidelines for the management of VLBW infants be set up.

Rail signallers' assessments of their satisfaction with different shift work systems

This paper describes rail employee views on shift-work systems obtained from administration of the Rail Ergonomics Questionnaire (REQUEST) to a large sample of rail professionals in Great Britain, achieving a response rate of 83%. Results from signallers, the largest occupational grouping in the survey (n = 3230), are presented. ANOVA has been used to investigate the effects of different aspects of the shift patterns (the length of shift and the speed and direction of rotation of shifts) and the effects of age on the ratings of satisfaction with the shift system. The findings from the analyses indicate preferences for the 12-h shift system over the 7-9-h rotating shift system. There were no main effects of the direction of rotation of shifts, though there were significant interactions between the direction of rotation of shifts, the numbers of consecutive shifts and the age of respondents. There is a need for clear data addressing the impact on workers of key shift-related parameters such as shift length, direction of rotation of shifts, numbers of consecutive shifts and personal factors such as age. This paper presents findings of the effects of these key shift and personal parameters and their interactions on respondents' ratings of satisfaction with the shift system, using data collected with REQUEST in a national survey of rail signallers.

Use of monensin controlled-release capsules to reduce methane emissions and improve milk production of dairy cows offered pasture supplemented with grain

We examined the effects of monensin, provided by controlled-release capsules, on the enteric methane emissions and milk production of dairy cows receiving ryegrass pasture and grain. In a grazing experiment, 60 Holstein-Friesian cows were assigned randomly to 1 of 2 groups (control or monensin). Cows in the monensin group received 2 controlled-release capsules, with the second capsule administered 130 d after the first. Milk production was measured for 100 d following insertion of each capsule. The sulfur hexafluoride tracer gas technique was used to measure enteric methane emissions for 4 d starting on d 25 and 81 after insertion of the first capsule, and on d 83 after insertion of the second capsule. All cows grazed together as a single herd on a predominantly ryegrass sward and received 5 kg/d of grain (as-fed basis). In a second experiment, 7 pairs of lactating dairy cows (control and monensin) were used to determine the effects of monensin controlled-release capsules on methane emissions and dry matter intake. Methane emissions were measured on d 75 after capsule insertion by placing cows in respiration chambers for 3 d. Cows received fresh ryegrass pasture harvested daily and 5 kg/d of grain. The release rate of monensin from the capsules used in both experiments was 240 +/- 0.072 mg/d, determined over a 100-d period in ruminally cannulated cows. The monensin dose was calculated to be 12 to 14.5 mg/kg of dry matter intake. There was no effect of monensin on methane production in either the grazing experiment (g/d, g/kg of milk solids) or the chamber experiment (g/d, g/kg of dry matter intake). In the grazing study, there was no effect of monensin on milk yield, but monensin increased milk fat yield by 51.5 g/d and tended to increase milk protein yield by 18.5 g/d. Monensin controlled-release capsules improved the efficiency of milk production of grazing dairy cows by increasing the yield of milk solids. However, a higher dose rate of monensin may be needed to reduce methane emissions from cows grazing pasture.

Incomplete milking has no detectable effect on somatic cell count but increased cell count appears to increase strip yield

Milking regimes that can greatly shorten the milking duration of slow-milking cows to improve labour productivity can also result in less complete milking for some cows. There is also a common belief and limited experimental evidence that incomplete milking of subclinically infected cows can cause increased somatic cell count (SCC). To test for this possible detrimental effect of shorter milking regimes, ‘complete’ milking [to automatic cluster remover (ACR) setting of 300 mL/min] and ‘incomplete’ milking (to an ACR setting of 800 mL/min) were applied sequentially to 45 cows over 7 weeks. Incomplete milking resulted in an average of 0.3 L of extra milk being left in the udders, but there was no significant increase in quarter SCC in either infected or uninfected udder quarters. Change in SCC was not related to change in strip yield induced by incomplete milking treatment. In contrast, cow strip yield was positively related to SCC, or the number of infected quarters/cow, regardless of the applied ACR treatment. These apparently contradictory findings are reconciled by noting that infection causes both high strip yields (via uneven yielding quarters) and high SCC. It is concluded that, contrary to popular belief, high SCC, as an indicator of infection, causes high strip yield and that increasing strip yield does not increase cell count.

Supplementation with whole cottonseed reduces methane emissions and can profitably increase milk production of dairy cows offered a forage and cereal grain diet

The experimental objective was to determine if whole cottonseed (WCS) could be used as a dietary supplement to reduce enteric methane emissions and profitably increase milk production from dairy cattle over the summer period when pasture is limited in quantity and has a low nutritive value. Fifty lactating cows, ~200 days in milk, were randomly allocated to one of two groups (control or WCS). Cows were offered lucerne hay (in the morning) and pasture silage (in the afternoon) made from a predominantly ryegrass sward in one group for 5 weeks. The hay and silage were placed on the ground in a bare paddock. Cows in each group were also individually offered cracked grain in a feed trough at 3 kg DM/cow.day at milking times. In addition, at milking times, cows in the WCS group were individually offered 2.7 kg DM/cow.day of untreated WCS with their grain supplement. Measurements of methane emissions (n = 12), using the SF6 tracer technique, were made in weeks 3 and 5 after the commencement of feeding treatments. Supplementation with WCS significantly reduced methane emissions by 12% (g/cow.day) and by 21% (g/cow.kg milk solids) and significantly increased yield of milk (n = 25) by 15%, milk fat by 19% and milk protein by 16%. WCS had no effect on concentration of milk fat or lactose, but resulted in a significant 3% decrease in protein concentration. WCS appears to be a promising supplement for reducing methane emissions and increasing milk production from dairy cattle when pasture is limited in quantity and has a low nutritive value.

Methane Emissions from Dairy Cows Measured Using the Sulfur Hexafluoride (SF6) Tracer and Chamber Techniques

Our study compared methane (CH4) emissions from lactating dairy cows measured using the sulfur hexafluoride (SF6) tracer and open-circuit respiration chamber techniques. The study was conducted using 16 lactating Holstein-Friesian cows. In each chamber, the cow was fitted with the SF6 tracer apparatus to measure total CH4 emissions, including emissions from the rectum. Fresh ryegrass pasture was harvested daily and fed ad libitum to each cow with a supplement of 5 kg of grain/d. The CH4 emissions measured using the SF6 tracer technique were similar to those using the chamber technique: 331 vs. 322 g of CH4/d per cow. The accuracy of the SF6 tracer technique was indicated by considering the ratio of the CH4 emission measured using the SF6 tracer to the emission measured using the chamber for each cow on each day. The calculated ratio of 102.3% (SE = 1.51) was not different from 100%. A higher variability within cow between days was found for the SF6 tracer technique [coefficient of variation (CV) = 6.1%] than for the chamber technique (CV = 4.3%). The variability among cows was substantially higher than within cows, and was higher for the SF6 technique (CV = 19.6%) than for the chamber technique (CV = 17.8%). Our CH4 emission data were compared with whole-animal chamber studies conducted in Canada and Ireland. In the Canadian study the SF6 technique did not measure CH4 emissions from the rectum and emissions were 8% lower than those measured using the chamber, indicating that emissions from the rectum may be greater than previously measured (1%). The relationship between CH4 emission and dry matter intake was examined for our data and for that reported in the Canadian study. There was a difference in the slopes of the regressions derived from our data and that from Canada; 17.1 vs. 20.8 g of CH4/kg of dry matter intake. A difference between the 2 locations was expected based on the difference in diet composition for these 2 studies. The SF6 tracer technique is reasonably accurate for inventory purposes and for evaluating the effects of mitigation strategies on CH4 emissions.

Benchmarking comparison survey of regional neonatal units

There are currently eight regional neonatal units in Ireland; three in Dublin and one each in Cork, Limerick, Galway, Drogheda and Waterford. Previous studies have shown a significant variation in the provision of care and services between such units. In July 2005, a postal questionnaire was distributed to a focus group of staff in the eight regional units. The objective was to identify issues of significant concern in current neonatology practice in Ireland. Eighteen people were surveyed in this focus group and we had an overall response rate of almost 78%. All of the respondents felt that there was a difference between practises in the neonatal units and greater than 90% perceived these to be significant. We believe that this study has identified the desire for standardisation of neonatology practises in Ireland and that this may be achieved by the introduction of a Nationwide Newborn Network.

A simple statistical model to estimate precision of 300-day milk and fat production for dairy cows

In this paper we use a statistical model to examine the relative precision of lactation milk yield and milk fat yield, under various production recording regimes with different metering and sampling precision, recording frequencies combined with empirical daily variations in milk yield and fat composition. The analysis shows that if traditional monthly production recording was performed with devices of International Committee for Animal Recording (ICAR) precision, the resultant coefficient of variation (CV) for lactation yields of milk and fat would be 2.22 and 4.81%, respectively. These values are determined primarily by measurement frequency coupled with the natural daily biological variations in animal milk yield and fat composition. Meter and sampler precision play a relatively minor role. For example, our model shows that if the devices had double the CV prescribed by ICAR, the milk and fat yield CV would increase by only 0.20 and 0.19%, respectively. These are minute losses of precision. If the ICAR precision standards for meters and samples were relaxed, it could encourage development of innovative metering and sampling technologies that could provide much more cost-effective and convenient ways for farmers to conduct production recording.

What information patients require on graduated compression stockings

Graduated compression stockings are used prophylactically on a variety of patients within acute hospitals. Anecdotal evidence suggests patients have a limited understanding of this treatment. The aim of this qualitative study was to explore patients' experiences of compression stockings and to ascertain perceptions of their use. Information was gathered using telephone interviews from a sample of 12 adults who had been patients within the past 2 months, and who had worn compression stockings for more than 48 hours. The results showed that patients received little or no information from healthcare staff regarding compression stockings, but that they did have knowledge from other sources, such as long-haul flight advice. This raises issues of informed consent and patient empowerment and highlights the need for both verbal and written information. The information gained informed a patient information leaflet, which was developed in partnership with a patient focus group.

Assessing intervention effects in a community-based trial to reduce self-harm: A methodological case study

This paper considers the assessment of the impact of a community-based randomized controlled trial to reduce repeat deliberate self-harm. It considers the drawbacks in simplistic applications of conventional significance testing procedures, as well as possible failures regarding the statistical assumptions underlying such tests. Instead, the paper considers how relevant prior information might be incorporated within a fully Bayesian-model-based assessment procedure. The model includes a latent trait approach to patient morbidity; controlling for morbidity and other patient characteristics enhances the impact of the intervention (measured by a hazard rate ratio). If allowance is made for external information (e.g. ethical approval of the treatment), the weight of evidence shifts towards a positive intervention effect.

Cytochrome c nitrite reductase: from structural to physicochemical analysis

The recent structural characterization of the NrfA from Escherichia coli provides a framework to rationalize the spectroscopic and functional properties of this enzyme. Analyses by EPR and magnetic CD spectroscopies have been complemented by protein-film voltammetry and these are discussed in relation to the essential structural features of the enzyme.

Perinatal factors influencing survival in extremely low-birthweight infants

The majority of deaths in normally formed infants occur in extremely low birth weight infants (< 1000 g). Survival rates for these infants have improved greatly but still vary from centre to centre and accurate local outcome figures are important for counselling parents and upholding standards of care. In the Rotunda Hospital, Dublin, over the 6 year period from 1 January 1990 to 31 December 1995, there were 34 474 deliveries over 500 g birthweight. One hundred and twenty-six of these were normally formed infants between 500 g and 999 g. Our objective was to analyse the factors influencing survival in these extremely low birthweight (ELBW) infants. Overall survival in the group was 63%. The most significant factors influencing survival to 28 days were gestation and birthweight. Survival increased from 33% at 24 weeks to 100% at 28 weeks' gestation and from 29% at 500-599 g to 87% at 900-999 g birthweight. Having controlled for gestational age, none of the following variables had a significant effect on survival: year of birth; gender; multiple pregnancy; 1-minute Apgar score; maternal age; parity; use of antenatal steroids; a history of antepartum haemorrhage, pre-eclamptic toxaemia or prolonged rupture of membranes. A 5-min Apgar score > 5 increased the chance of survival by 3.97 (95% CI: 1.46- 10). Both mode of delivery and incidence of chorioamnionitis had an influence on survival which varied according to the gestational age. A larger cohort of survivors would illustrate the effect of these variables more clearly.

Work-related stress among paediatric non-consultant hospital doctors

There have been many reports of Non-Consultant Hospital Doctors (NCHDs) deciding to leave hospital medicine in pursuit of a career with better hours and lifestyle such as general practice. It is not known, however, how widespread feelings of dissatisfaction are in paediatrics and whether work-related stress is a contributing factor. A postal survey of NCHDs in paediatric posts throughout the country was conducted in November 2000. Data collected included demographic and personal details. NCHDs were also asked their level of stress in relation to their daily work, patient-care, hospital environment and dealing with other staff members using an incremental scale from 1 to 5 (5 most stressed). 69% (71/103) of the questionnaires were returned. Equal numbers of males and females responded (48% vs 52%). 51% (36/71) of the NCHDs were registrars; 51% (36/71) were working within Dublin. More than three-quarters had graduated from a European Union (EU) medical school (77%, 55/71). While the majority (79%, 56/71) were either satisfied or very satisfied with paediatrics as their chosen specialty, 79% (56/71) admitted to work-related stress causing job dissatisfaction with 71% (50/71) having experienced 3 or more stressful situations in the previous week. 56% (41/71) graded their occupational stress level at 4 or 5. Routine non-medical work and poor job prospects were the main factors causing job dissatisfaction. With regard to daily duties, the situations causing stress were acute emergency situations (51%, 36/71), being solely responsible for patients when on-call (52%, 19/36) and making decisions after a night on-call (76%, 50/67). The general attitudes of nursing staff were stressful to 40% (28/71) with 39% (27/71) stating having a difference of opinion with a nurse at least once every week. Relating to consultants was moderately stressful to 26% (19/71) and very stressful to 4% (3/71). Uncomfortable sleeping quarters and having insufficient time for meals were noted to be at least moderately stressful (stress levels 3 to 5) for 70% (50/71) and 92% (65/71) respectively. 59% (42/71) felt that their social life was greatly affected by their work. 68% (48/71) have considered leaving paediatrics with almost half (48%, 23/48) considering this seriously or very seriously. More than half stated that their alternative career choice would be general practice (61%, 29/48). The results of our survey show that work-related stress is common among paediatric NCHDs and is associated mainly with long working hours, sub-optimal on-call conditions, and dealing with very ill patients.

Effects of breathing air containing 3% carbon dioxide, 35% oxygen or a mixture of 3% carbon dioxide/35% oxygen on cerebral and peripheral oxygenation at 150 m and 3459 m

The effects of gas mixtures comprising supplementary 3% carbon dioxide, 35% oxygen or a combination of 3% CO(2) plus 35% O(2) in ambient air have been compared on arterial blood gases, peripheral and cerebral oxygenation and middle cerebral artery velocity (MCAV) at 150 m and on acute exposure to 3459 m in 12 healthy subjects. Breathing 3% CO(2) or 35% O(2) increased arterial blood oxygen at both altitudes, and the CO(2)/O(2) combination resulted in the most marked rise. MCAV increased on ascent to 3459 m, increasing further with 3% CO(2) and decreasing with 35% O(2) at both altitudes. The CO(2)/O(2) combination resulted in an increase in MCAV at 150 m, but not at 3549 m. Cerebral regional oxygenation fell on ascent to 3459 m. Breathing 3% CO(2) or 35% O(2) increased cerebral oxygenation at both altitudes, and the CO(2)/O(2) combination resulted in the greatest rise at both altitudes. The combination also resulted in significant rises in cutaneous and muscle oxygenation at 3459 m. The key role of carbon dioxide in oxygenation at altitude is confirmed, and the importance of this gas for tissue oxygenation is demonstrated.

Evidence for separate disease phenotypes in intestinal Crohn's disease

Background

This study investigated the hypothesis that separate phenotypes of Crohn's disease exist which display differing patterns of recurrence with a tendency to preservation of phenotype between serial operations.

Methods

Some 483 abdominal operations (278 patients) were identified from a prospectively compiled database. Patterns of recurrence (reoperation) were analysed by Kaplan–Meier plots and log rank tests according to disease phenotype (perforated, stenosed or ulcerated). Serial operations were analysed by agreement of phenotype and microscopic features of disease using kappa statistics and correlation coefficients.

Results

There was no significant difference in recurrence according to disease phenotype (median reoperation-free survival time 43·0, 50·2 and 47·9 months for perforated, stenosed and ulcerated types respectively; log rank χ2 = 3·5, P = 0·18). There was poor agreement in phenotype between serial operations (κ = 0·22 for first/second operation and κ = 0·15 for second/third operation) and no significant correlation between pathological features was identified (r between −0·19 and 0·48).

Conclusion

No evidence was found for the existence of separate disease phenotypes with differing natural histories or underlying pathological characteristics.

Can pre-colposcopy sessions reduce anxiety at the time of colposcopy? A prospective randomised study

The main objective of this prospective randomised study was to evaluate whether offering pre-colposcopy group sessions reduces anxiety at the time of colposcopy. We also examined whether this strategy improved knowledge about abnormal smears and colposcopy and improved satisfaction with the colposcopy service provided. One hundred and forty-seven women undergoing colposcopy for the first time were randomised into two groups. The control group (n = 75) received conventional management. The study group (n = 72), in addition to conventional management, were invited to attend a pre-colposcopy group session led by a trained colposcopy nurse. Questionnaires were used to determine state anxiety inventory scores and knowledge scores at the time of randomisation, immediately before colposcopy and 6 weeks after the clinic visit. Satisfaction questionnaires were completed 6 weeks after the clinic visit. We found that women attending colposcopy clinics are anxious. Those women who attended the pre-colposcopy session had improved knowledge scores (P = 0.039) at the time of colposcopy and satisfaction (P = 0.037). However, the intervention failed to significantly reduce anxiety at the time of colposcopy (P > 0.05).

Near-infrared spectroscopy in the assessment of cerebral oxygenation at high altitude

Hypoxia plays a key role in the pathogenesis of acute mountain sickness (AMS), but individual susceptibility is variable and cerebral symptoms do not always correlate with PaO2 measurements. Cerebral hypoxia may be more relevant than PaO2. We studied trends in cerebral regional oxygen saturation by the technique of near-infrared spectroscopy in 20 subjects ascending rapidly to 4680 m. Subjects were enrolled in a placebo-controlled, double-blind trial of medroxyprogesterone for the prevention of AMS. The fall in cerebral oxygen saturation was less than in the periphery. At 4680 m, cerebral oxygenation correlated with peripheral saturation but not with PaCO2 or with cerebral symptoms scores. At 4680 m, subjects on medroxyprogesterone had higher cerebral and peripheral saturation compared with those on a placebo. We conclude that cerebral oxygenation monitored with the Critikon 2020 system provided important information on the complex relationship of hypoxia to AMS and that other factors, such as changes in blood flow or capillary permeability, may be equally important.