Surgical and Radiology Trainees' Proficiency in Reading Mammograms: the Importance of Education for Cancer Localisation

Medical imaging with mammography plays a very important role in screening and diagnosis of breast cancer, Australia's most common female cancer. The visualisation of cancers on mammograms often forms a diagnosis and guidance for radiologists and breast surgeons, and education platforms that provide real cases in a simulated testing environment have been shown to improve observer performance for radiologists. This study reports on the performance of surgical and radiology trainees in locating breast cancers. An enriched test set of 20 mammography cases (6 cancer and 14 cancer free) was created, and 18 surgical trainees and 32 radiology trainees reviewed the cases via the Breast Screen Reader Assessment Strategy (BREAST) platform and marked any lesions identifiable. Further analysis of performance with high- and low-density cases was undertaken, and standard metrics including sensitivity and specificity. Radiology trainees performed significantly better than surgical trainees in terms of specificity (0.72 vs. 0.35; P < 0.01). No significant differences were observed between the surgical and radiology trainees in sensitivity or lesion sensitivity. Mixed results were obtained with participants regarding breast density, with higher density cases generally having lower performance. The higher specificity of the radiology trainees compared to the surgical trainees likely represents less exposure to negative mammography cases. The use of high-fidelity simulated self-test environments like BREAST is able to benchmark, understand and build strategies for improving cancer education in a safe environment, including identifying challenging scenarios like breast density for enhanced training.

1127 Utility of Quantitative EEG During Sleep as a Potential Biomarker of Lewy Body Disease Progression

Introduction

Sleep disturbances are common among patients with Lewy body disorders. Idiopathic REM sleep behavior disorder (iRBD) has been identified as a prodromal Lewy body condition with a significantly increased risk of conversion to either Parkinson’s disease (PD) or Dementia with Lewy Bodies (DLB). Pathological involvement of thalamic and brainstem structures involved in sleep regulation has been reported in these disorders, especially in later stages. We hypothesized that progression along the Lewy body disease spectrum may be associated with unique changes in spindle density and EEG power spectra during sleep reflecting involvement of these deep brain structures.

Methods

A cross-sectional design was used. 9 polysomnography confirmed iRBD, 18 early PD, 23 DLB and 13 controls underwent overnight polysomnography, neurological and neuropsychological assessment. Power spectrum analysis during NREM and REM sleep was undertaken using a previously validated quantitative EEG algorithm and compared between groups. Following artefact and outlier removal, results were analysed using the Cz derivation. Groups were statistically compared with a non-parametric Jonckheree-Terpstra test for ordered alternatives, controlling for age and sex.

Results

We found a significant and ordered reduction in power in the spindle frequency band (12-15 Hz) in NREM sleep across the Lewy body disease spectrum compared to controls (Controls &gt; iRBD &gt; early PD &gt; DLB; TJT = 521.00, z = -2.902. p&lt;0.001). In REM sleep we found a shift in power to slower frequencies with increased power in the theta (4.5-8 Hz) band in order of disease severity (DLB &gt; early PD &gt; iRBD &gt; Controls; TJT = 950.00, z = 2.253. p=0.024). No differences were found across the other frequency bands in NREM or REM sleep.

Conclusion

There is a significant and progressive reduction in spindle density and corresponding slowing in REM sleep frequencies during sleep with clinical Lewy body staging. Thus, such measures have the potential to be useful biomarkers of progression towards Lewy body dementia from prodromal stages.

Support

This work was supported by a NHMRC Dementia Team Grant (#1095127), the NHMRC Postgraduate Scholarship and the University of Sydney Research Excellence Initiative 2020 grant.

Pathways to mental health improvement in a community-led area-based empowerment initiative: evidence from the Big Local 'Communities in Control' study, England

BACKGROUND

Area-based initiatives that include a focus on community empowerment are increasingly being seen as potentially an important way of improving health and reducing inequalities. However, there is little empirical evidence on the pathways between communities having more control and health outcomes.

PURPOSE

To identify pathways to health improvement in a community-led area-based community empowerment initiative.

METHODS

Longitudinal data on mental health, community control, area belonging, satisfaction, social cohesion and safety were collected over two time points, 6 months apart from 48 participants engaged in the Big Local programme, England. Qualitative comparative analysis (QCA) was used to explore pathways to health improvement.

RESULTS

There was no clear single pathway that led to mental health improvement but positive changes in 'neighbourhood belonging' featured in 4/5 health improvement configurations. Further, where respondents experienced no improvement in key social participation/control factors, they experienced no health improvement.

CONCLUSION

This study demonstrates a potential pathway between an improvement in 'neighbourhood belonging' and improved mental health outcomes in a community empowerment initiative. Increasing neighbourhood belonging could be a key target for mental health improvement interventions.

Quantitative data analysis of perceived barriers and motivators to physical activity in stroke survivors

BACKGROUND

Levels of physical activity after stroke are low, despite multiple health benefits. We explored stroke survivors' perceived barriers, motivators, self-efficacy and intention to physical activity.

METHODS

Fifty independently mobile stroke survivors were recruited prior to hospital discharge. Participants rated nine possible motivators and four possible barriers based on the Mutrie Scale, as having 'no influence', 'some influence' or 'a major influence' on physical activity. Participants also rated their self-efficacy and intention to increasing walking.

RESULTS

The most common motivator was 'physical activity is good for health' [34 (68%)]. The most common barrier was 'feeling too tired' [24 (48%)]. Intention and self-efficacy were high. Self-efficacy was graded as either 4 or 5 (highly confident) on a five-point scale by [34 (68%)] participants, while 42 (84%) 'strongly agreed' or 'agreed' that they intended to increase their walking.

CONCLUSION

Participants felt capable of increasing physical activity but fatigue was often perceived as a barrier to physical activity. This needs to be considered when encouraging stroke survivors to be more active.

Randomized clinical trial of postoperative chewing gum versus standard care after colorectal resection

Background

Chewing gum may stimulate gastrointestinal motility, with beneficial effects on postoperative ileus suggested in small studies. The primary aim of this trial was to determine whether chewing gum reduces length of hospital stay (LOS) after colorectal resection. Secondary aims included examining bowel habit symptoms, complications and healthcare costs.

Methods

This clinical trial allocated patients randomly to standard postoperative care with or without chewing gum (sugar‐free gum for at least 10 min, four times per day on days 1–5) in five UK hospitals. The primary outcome was LOS. Cox regression was used to calculate hazard ratios for LOS.

Results

Data from 402 of 412 patients, of whom 199 (49·5 per cent) were allocated to chewing gum, were available for analysis. Some 40 per cent of patients in both groups had laparoscopic surgery, and all study sites used enhanced recovery programmes. Median (i.q.r.) LOS was 7 (5–11) days in both groups (P = 0·962); the hazard ratio for use of gum was 0·94 (95 per cent c.i. 0·77 to 1·15; P = 0·557). Participants allocated to gum had worse quality of life, measured using the EuroQoL 5D‐3L, than controls at 6 and 12 weeks after operation (but not on day 4). They also had more complications graded III or above according to the Dindo–Demartines–Clavien classification (16 versus 6 in the group that received standard care) and deaths (11 versus 0), but none was classed as related to gum. No other differences were observed.

Conclusion

Chewing gum did not alter the return of bowel function or LOS after colorectal resection. Registration number: ISRCTN55784442 (http://www.controlled-trials.com).

No advantage observed

Ovarian cancer screening and mortality in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS): a randomised controlled trial

BACKGROUND

Ovarian cancer has a poor prognosis, with just 40% of patients surviving 5 years. We designed this trial to establish the effect of early detection by screening on ovarian cancer mortality.

METHODS

In this randomised controlled trial, we recruited postmenopausal women aged 50-74 years from 13 centres in National Health Service Trusts in England, Wales, and Northern Ireland. Exclusion criteria were previous bilateral oophorectomy or ovarian malignancy, increased risk of familial ovarian cancer, and active non-ovarian malignancy. The trial management system confirmed eligibility and randomly allocated participants in blocks of 32 using computer-generated random numbers to annual multimodal screening (MMS) with serum CA125 interpreted with use of the risk of ovarian cancer algorithm, annual transvaginal ultrasound screening (USS), or no screening, in a 1:1:2 ratio. The primary outcome was death due to ovarian cancer by Dec 31, 2014, comparing MMS and USS separately with no screening, ascertained by an outcomes committee masked to randomisation group. All analyses were by modified intention to screen, excluding the small number of women we discovered after randomisation to have a bilateral oophorectomy, have ovarian cancer, or had exited the registry before recruitment. Investigators and participants were aware of screening type. This trial is registered with ClinicalTrials.gov, number NCT00058032.

FINDINGS

Between June 1, 2001, and Oct 21, 2005, we randomly allocated 202,638 women: 50,640 (25·0%) to MMS, 50,639 (25·0%) to USS, and 101,359 (50·0%) to no screening. 202,546 (>99·9%) women were eligible for analysis: 50,624 (>99·9%) women in the MMS group, 50,623 (>99·9%) in the USS group, and 101,299 (>99·9%) in the no screening group. Screening ended on Dec 31, 2011, and included 345,570 MMS and 327,775 USS annual screening episodes. At a median follow-up of 11·1 years (IQR 10·0-12·0), we diagnosed ovarian cancer in 1282 (0·6%) women: 338 (0·7%) in the MMS group, 314 (0·6%) in the USS group, and 630 (0·6%) in the no screening group. Of these women, 148 (0·29%) women in the MMS group, 154 (0·30%) in the USS group, and 347 (0·34%) in the no screening group had died of ovarian cancer. The primary analysis using a Cox proportional hazards model gave a mortality reduction over years 0-14 of 15% (95% CI -3 to 30; p=0·10) with MMS and 11% (-7 to 27; p=0·21) with USS. The Royston-Parmar flexible parametric model showed that in the MMS group, this mortality effect was made up of 8% (-20 to 31) in years 0-7 and 23% (1-46) in years 7-14, and in the USS group, of 2% (-27 to 26) in years 0-7 and 21% (-2 to 42) in years 7-14. A prespecified analysis of death from ovarian cancer of MMS versus no screening with exclusion of prevalent cases showed significantly different death rates (p=0·021), with an overall average mortality reduction of 20% (-2 to 40) and a reduction of 8% (-27 to 43) in years 0-7 and 28% (-3 to 49) in years 7-14 in favour of MMS.

INTERPRETATION

Although the mortality reduction was not significant in the primary analysis, we noted a significant mortality reduction with MMS when prevalent cases were excluded. We noted encouraging evidence of a mortality reduction in years 7-14, but further follow-up is needed before firm conclusions can be reached on the efficacy and cost-effectiveness of ovarian cancer screening.

FUNDING

Medical Research Council, Cancer Research UK, Department of Health, The Eve Appeal.

In the digital era, architectural distortion remains a challenging radiological task

AIM

To compare readers' performance in detecting architectural distortion (AD) compared with other breast cancer types using digital mammography.

MATERIALS AND METHODS

Forty-one experienced breast screen readers (20 US and 21 Australian) were asked to read a single test set of 30 digitally acquired mammographic cases. Twenty cases had abnormal findings (10 with AD, 10 non-AD) and 10 cases were normal. Each reader was asked to locate and rate any abnormalities. Lesion and case-based performance was assessed. For each collection of readers (US; Australian; combined), jackknife free-response receiver operating characteristic (JAFROC), figure of merit (FOM), and inferred receiver operating characteristic (ROC), area under curve (Az) were calculated using JAFROC v.4.1 software. Readers' sensitivity, location sensitivity, JAFROC, FOM, ROC, Az scores were compared between cases groups using Wilcoxon's signed ranked test statistics.

RESULTS

For lesion-based analysis, significantly lower location sensitivity (p=0.001) was shown on AD cases compared with non-AD cases for all reader collections. The case-based analysis demonstrated significantly lower ROC Az values (p=0.02) for the first collection of readers, and lower sensitivity for the second collection of readers (p=0.04) and all-readers collection (p=0.008), for AD compared with non-AD cases.

CONCLUSIONS

The current work demonstrates that AD remains a challenging task for readers, even in the digital era.

Assessing the effect of a true-positive recall case in screening mammography: does perceptual priming alter radiologists' performance?

OBJECTIVE

To measure the effect of the insertion of less-difficult malignant cases on subsequent breast cancer detection by breast imaging radiologists.

METHODS

The research comprises two studies. Study 1: 8 radiologists read 2 sets of images each consisting of 40 mammographic cases. Set A contained four abnormal cases, and Set B contained six abnormal cases, including two priming cases (less difficult malignancies) placed at intervals of three and five subsequent cases before a subtle cancer. Study 2: 16 radiologists read a third condition of the same cases, known as Set C, containing six abnormal cases and two priming cases immediately preceding the subtle cancer cases. The readers were asked to localize malignancies and give confidence ratings on decisions.

RESULTS

Although not significant, a decrease in performance was observed in Set B compared with in Set A. There was a significant increase in the receiver operating characteristic (ROC) area under the curve (z = -2.532; p = 0.0114) and location sensitivity (z = -2.128; p = 0.0333) between the first and second halves of Set A and a marginal improvement in jackknife free-response ROC figure of merit (z = -1.89; p = 0.0587) between the first and second halves of Set B. In Study 2, Set C yielded no significant differences between the two halves of the study.

CONCLUSION

Overall findings show no evidence that priming with lower difficulty malignant cases affects the detection of higher difficulty cancers; however, performance may decrease with priming.

ADVANCES IN KNOWLEDGE

This research suggests that inserting additional malignant cases in screening mammography sets as an audit tool may potentially lead to a decrease in performance of experienced breast radiologists.

Attendance at iron deficiency anaemia clinic: audit of outcomes 5 years on

AIM

To determine the long-term outcomes of patients in whom no initial cause for their anaemia is established.

METHOD

Six hundred and thirty-nine patients presenting to an iron deficiency anaemia pathway were prospectively entered onto a database. Initial assessment included haematological review, coeliac screen, oesophagogastroduodenoscopy and colonic imaging as per British Society of Gastroenterology guidelines. A 5-year audit of outcomes was undertaken using patient medical records and hospital laboratory databases.

RESULTS

A diagnosis was found initially in 266 (42%) patients, with 124 (19%) having a gastrointestinal (GI) luminal neoplasm, 54 (8%) of which were malignant. Twelve patients had a nonluminal or non-GI malignancy. Eighty-eight (14%) had benign upper GI bleeding and 23 (4%) had coeliac disease. One hundred and forty-three (22%) did not have confirmed iron deficiency anaemia on review of haematinics. Complete records were available for 595 (93%) patients at 5 years. Of the 373 patients in whom a cause was not initially diagnosed, 6 (2%) were ultimately diagnosed with a GI luminal malignancy and 18 (5%) with a nonluminal or non-GI malignancy. There was no difference in the incidence of malignancies between those with or without confirmed iron deficiency.

CONCLUSIONS

Most patients in whom no cause was found at initial investigation resolve on oral iron supplements. Patients with normal ferritin values had as high an incidence of GI malignancies as those with low values and should be investigated. In the over 50s if the anaemia remains after a course of iron further investigation is recommended as there is a significant incidence of both GI and non-GI pathology.

Noise-reducing algorithms do not necessarily provide superior dose optimisation for hepatic lesion detection with multidetector CT

OBJECTIVE

To compare the dose-optimisation potential of a smoothing filtered backprojection (FBP) and a hybrid FBP/iterative algorithm to that of a standard FBP algorithm at three slice thicknesses for hepatic lesion detection with multidetector CT.

METHODS

A liver phantom containing a 9.5-mm opacity with a density of 10 HU below background was scanned at 125, 100, 75, 50 and 25 mAs. Data were reconstructed with standard FBP (B), smoothing FBP (A) and hybrid FBP/iterative (iDose(4)) algorithms at 5-, 3- and 1-mm collimation. 10 observers marked opacities using a four-point confidence scale. Jackknife alternative free-response receiver operating characteristic figure of merit (FOM), sensitivity and noise were calculated.

RESULTS

Compared with the 125-mAs/5-mm setting for each algorithm, significant reductions in FOM (p<0.05) and sensitivity (p<0.05) were found for all three algorithms for all exposures at 1-mm thickness and for all slice thicknesses at 25 mAs, with the exception of the 25-mAs/5-mm setting for the B algorithm. Sensitivity was also significantly reduced for all exposures at 3-mm thickness for the A algorithm (p<0.05). Noise for the A and iDose(4) algorithms was approximately 13% and 21% lower, respectively, than for the B algorithm.

CONCLUSION

Superior performance for hepatic lesion detection was not shown with either a smoothing FBP algorithm or a hybrid FBP/iterative algorithm compared with a standard FBP technique, even though noise reduction with thinner slices was demonstrated with the alternative approaches.

ADVANCES IN KNOWLEDGE

Reductions in image noise with non-standard CT algorithms do not necessarily translate to an improvement in low-contrast object detection.

Grey-scale inversion improves detection of lung nodules

Objective The current study aims to establish whether detection of solitary pulmonary nodules can be improved by inverting the grey scale of posteroanterior (PA) chests. Methods 30 PA chest images were presented on 2 occasions to 16 senior radiologists on either primary or secondary class displays in the standard or inverted mode. 15 images within each group contained a single nodule positioned in a range of anatomical sites. A receiver operating characteristic (ROC) methodology was used to explore differences between the presentation modes. Results Improved ROC scores were evident with inverted (Az 0.77) compared with standard (Az 0.73) (p=0.02) images; however, this difference was seen only with the primary displays. The benefits seen are most likely owing to increased nodule luminance with the inverted images, particularly when using primary displays. Conclusion This study demonstrates that the inverted image can offer advantages in lung nodule detection over the standard presentation mode when images are viewed on high-specification viewing systems. The study has demonstrated that there is an improvement in the detectability of lung nodules on an inverted image with a primary display monitor that is not evident with secondary displays. This is likely to be the result of increased nodule luminance on primary displays when images are presented in the inverted mode.

Rate and risk predictors for development of self-reported type-2 diabetes mellitus over a 5-year period: the SHIELD study

AIMS

This investigation determined the proportion of adults newly diagnosed as having type-2 diabetes mellitus (T2DM), and ascertained risk predictors for development of self-reported T2DM.

METHODS

The US Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD) survey was a 5-year longitudinal study of adults with and without diabetes mellitus. Adults completed a baseline health questionnaire in 2004 and ≥1 annual follow-up survey through 2009. Respondents with no self-reported diagnosis of diabetes at baseline were followed to measure rate of and assess risk factors for development of T2DM over 5 years.

RESULTS

Among 8582 respondents without diabetes at baseline, 622 (7.2%) reported a diagnosis of T2DM over the subsequent 5 years. Increasing age, family history of T2DM, body mass index ≥30 kg/m(2), abdominal obesity, excessive thirst, asthma, gestational diabetes and 'high blood sugar without diabetes' significantly increased the risk of developing T2DM (p < 0.05 for each). Good to excellent health status and self-reported circulatory problems decreased the risk (p < 0.05 for each).

CONCLUSIONS

Among this representative US adult population, the rate of developing T2DM was 7.2% over 5 years. Predictors of T2DM diagnosis identified in this analysis were readily obtainable via self-report.

Grey-scale inversion improves detection of lung nodules

OBJECTIVE

The current study aims to establish whether detection of solitary pulmonary nodules can be improved by inverting the grey scale of posteroanterior (PA) chests.

METHODS

30 PA chest images were presented on 2 occasions to 16 senior radiologists on either primary or secondary class displays in the standard or inverted mode. 15 images within each group contained a single nodule positioned in a range of anatomical sites. A receiver operating characteristic (ROC) methodology was used to explore differences between the presentation modes.

RESULTS

Improved ROC scores were evident with inverted (Az 0.77) compared with standard (Az 0.73) (p=0.02) images; however, this difference was seen only with the primary displays. The benefits seen are most likely owing to increased nodule luminance with the inverted images, particularly when using primary displays.

CONCLUSION

This study demonstrates that the inverted image can offer advantages in lung nodule detection over the standard presentation mode when images are viewed on high-specification viewing systems. The study has demonstrated that there is an improvement in the detectability of lung nodules on an inverted image with a primary display monitor that is not evident with secondary displays. This is likely to be the result of increased nodule luminance on primary displays when images are presented in the inverted mode.

Folic acid supplementation during pregnancy may protect against depression 21 months after pregnancy, an effect modified by MTHFR C677T genotype

BACKGROUND/OBJECTIVES

As low folate status has been implicated in depression, high folate intake, in the form of supplements, during pregnancy might offer protection against depression during pregnancy and postpartum.

SUBJECTS/METHODS

We examined the association between change in self-reported depressive symptoms (Edinburgh Postnatal Depression Scale) at different timepoints during and following pregnancy and self-reported folic acid supplementation during pregnancy in a prospective cohort of 6809 pregnant women. We also tested whether there was a main effect of methylenetetrahydrofolate reductase (MTHFR) C677T genotype (which influences folate metabolism and intracellular levels of folate metabolites and homocysteine) on change in depression scores, and carried out our analysis of folic acid supplementation and depression stratifying by genotype.

RESULTS

We found no strong evidence that folic acid supplementation reduced the risk of depression during pregnancy and up to 8 months after pregnancy. However, we did find evidence to suggest that folic acid supplements during pregnancy protected against depression 21 months postpartum, and that this effect was more pronounced in those with the MTHFR C677T TT genotype (change in depression score from 8 months to 21 months postpartum among TT individuals was 0.66 (95% CI=0.31-1.01) among those not taking supplements, compared with -1.02 (95% CI=-2.22-0.18) among those taking supplements at 18 weeks pregnancy, P(difference)=0.01).

CONCLUSIONS

Low folate is unlikely to be an important risk factor for depression during pregnancy and for postpartum depression, but may be a risk factor for depression outside of pregnancy, especially among women with the MTHFR C677T TT genotype.

Underutilisation of cardiovascular medications among at-risk individuals

AIMS

Guidelines recommend antihypertensive, lipid-lowering and/or antiplatelet therapy for prevention of cardiovascular disease (CVD). This study examined the utilisation of cardiovascular therapies among individuals at CVD risk to assess adherence to guidelines.

METHODS

Respondents to the SHIELD study were classified based on National Cholesterol Education Program Adult Treatment Panel III risk categories. High coronary heart disease (CHD) risk (n = 7510) was defined as self-reported diagnosis of heart disease/heart attack, narrow or blocked arteries, stroke or diabetes; moderate risk (n = 4823) included respondents with > or = 2 risk factors (i.e., men > 45 years, women > 55 years, hypertension, low high-density lipoprotein cholesterol, smoking and family history of CHD); and low risk (n = 5307) was 0-1 risk factor. Respondents reporting a myocardial infarction, stroke or revascularisation at baseline (prior CVD event) (n = 3777), those reporting a new CVD event during 2 years of follow up (n = 953), and those with type 2 diabetes mellitus (n = 3937) were evaluated. The proportion of respondents reporting treatment with lipid-lowering, antiplatelet or antihypertensive agents was calculated.

RESULTS

Utilisation of lipid-lowering therapy was low (< or = 25%) in each group. Prescription antithrombotic therapy was minimal among respondents with prior CVD events, but 47% received antihypertensive medication. No use before or after a new CVD event was reported by 36% of respondents for lipid-lowering, 32% for antithrombotic and > 50% for antihypertensive medications.

CONCLUSIONS

More than 50% of at-risk respondents and > 33% of respondents with new CVD events were not taking CVD therapy as recommended by guidelines.

Black walnut extract-induced laminitis in horses is associated with heterogeneous dysfunction of the laminar microvasculature

REASONS FOR PERFORMING STUDY

Equine laminitis purportedly involves haemodynamic dysfunction at the level of the laminar vasculature. However, to date, no studies have been performed characterising the function of laminar arteries and veins during the prodromal stages of equine laminitis.

HYPOTHESIS

That the prodromal stages of laminitis are associated with contractile dysfunction of the equine laminar vasculature.

OBJECTIVE

To assess contractile function of laminar arteries and veins to phenylephrine (PE) and 5-hydroxytryptamine (5-HT).

METHODS

Horses were administered black walnut heartwood extract (BWHE) or water (control horses) via nasogastric intubation. After euthanasia, laminar vessels (100-800 microm internal diameter) were isolated and mounted on small vessel myographs to assess contractile function.

RESULTS

Contractile responses to PE or 5-HT were identical in laminar arteries isolated from either control horses or those administered BWHE. In contrast, responses to PE or 5-HT were significantly reduced in laminar veins isolated from BWHE-administered horses when compared with laminar veins isolated from control horses.

CONCLUSIONS AND POTENTIAL RELEVANCE

These results are consistent with the prodromal stages of laminitis being associated with selective dysfunction of laminar veins. Further studies are required to discern the precise nature of this dysfunction and its potential relevance to the pathogenesis of acute laminitis in the horse and possible therapeutic targets for treatment.

PTGS2-899G>C and prostate cancer risk: a population-based nested case-control study (ProtecT) and a systematic review with meta-analysis

Prostaglandin endoperoxidase synthase 2 is a key regulator of inflammation and may play a role in prostate carcinogenesis. The polymorphism, -899G>C (rs20417), alters a transcription factor-binding site and is associated with a reduced risk of colorectal adenoma. We tested the hypothesis that rs20417 may influence prostate cancer risk, using a large case-control study (n(cases)=1608, n(controls)=3058). We found no evidence that rs20417 alters prostate cancer risk (odds ratio (OR(CC & GC v GG)=1.05, 95% confidence interval (CI)=0.91-1.20). A meta-analysis of three studies also found little evidence that rs20417 alters risk (pooled OR(CC & GC v GG)=1.04, 95% CI=0.93-1.17), making it unlikely that rs20417 contributes in any major way to prostate cancer aetiology.

Self-reported diagnosis of heart disease: results from the SHIELD study

OBJECTIVE

This study evaluated the self-reported method of diagnosis of heart disease (HD) to elucidate whether diagnosis is occurring at early, presymptomatic stages as recommended by the prevention guidelines.

METHODS

Respondents to the 2006 survey in the US population-based Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD) reported whether a physician told them that they had HD, including heart attack, angina, heart failure, angioplasty or heart bypass surgery. Self-report of age at diagnosis, specialty of physician who made the diagnosis and whether the diagnosis was made after having symptoms, during routine screening or while being treated for another health problem were assessed. Year of diagnosis was categorised into 3-year intervals from 1985 to 2006. Individuals with HD diagnosis with and without type 2 diabetes mellitus (T2DM) were compared using chi-square tests.

RESULTS

Of 1573 respondents reporting a diagnosis of HD, > 87% were white, > 49% were men and 38% had T2DM. Approximately 19% of respondents reported that their HD diagnosis was made during routine screening. A significantly greater percentage of HD respondents with T2DM reported the diagnosis being made based on symptoms (54%) and while being treated for another health problem (22%) compared with respondents without diabetes (48% symptoms and 15% other health problem, p > 0.05). HD was diagnosed primarily by cardiologists (> 60%) and family doctors (> 25%).

CONCLUSION

There remains a missed opportunity to diagnose HD at earlier stages through routine screening or during treatment of other health conditions such as diabetes, as many individuals were not diagnosed until they were symptomatic.

Self-reported prevalence and awareness of metabolic syndrome: findings from SHIELD

PURPOSE

This study assessed awareness of metabolic syndrome and evaluated health knowledge, attitudes and behaviours of respondents at risk.

METHODS

Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD), a longitudinal US population-based survey initiated in 2004, included respondents, > or = 18 years of age, reporting a diagnosis of metabolic syndrome. Prevalence of metabolic syndrome was compared in SHIELD and National Health and Nutrition Examination Survey (NHANES) 1999-2002 survey. The proportion of SHIELD respondents who had heard of and/or understood metabolic syndrome was estimated. Respondents at high risk for metabolic syndrome were stratified into attitude-behaviour categories of 'Already Doing It', 'I Know I Should' and 'Don't Bother Me' and differences in attitudes and behaviours were evaluated with chi-square tests.

RESULTS

Prevalence of reported metabolic syndrome was 0.6% in SHIELD screening questionnaire respondents (n = 211,097) vs. 25.9% in NHANES (n = 10,780). Less than 15% of SHIELD baseline questionnaire respondents (n = 22,001) had heard of or understood metabolic syndrome. Attitudes toward health status were more favourable in the 'Doing' group (27% reported fair/poor health) compared with those in the 'Should' (38%) and 'Don't' (54%) groups (p < 0.0001). The 'Don't' group was most likely to prefer medications to lifestyle change (13% vs. 2-4%) compared with 'Should' and 'Doing' groups (p < 0.0001). More 'Doing' respondents (79%) than 'Should' (59%) and 'Don't' (48%) respondents reported exercising regularly (p < 0.0001).

CONCLUSIONS

The lack of knowledge about metabolic syndrome reported in SHIELD indicates limited penetration of this concept into public awareness. With behaviour categories, respondents who report healthy attitudes are more likely to embrace lifestyle changes, while respondents who do not care may be more difficult to treat.

Beneficial effects of aggressive low-density lipoprotein cholesterol lowering in women with stable coronary heart disease in the Treating to New Targets (TNT) study

OBJECTIVE

To examine by secondary analysis of the Treating to New Targets (TNT) study whether the benefits of intensive versus standard levels of lipid lowering are equally applicable to women.

METHODS

A total of 10 001 patients (1902 women) with stable coronary heart disease (CHD) were randomised to double-blind treatment with atorvastatin 10 or 80 mg/day for a median follow-up of 4.9 years.

RESULTS

In women and men, intensive treatment with atorvastatin 80 mg significantly reduced the rate of major cardiovascular events compared with atorvastatin 10 mg. Among women, the relative and absolute reductions were 27% and 2.7%, respectively (hazard ratio (HR) = 0.73, 95% confidence interval (CI) 0.54 to 1.00, p = 0.049). In men, the corresponding rate reductions were 21% and 2.2% (HR = 0.79, 95% CI 0.69 to 0.91, p = 0.001). The number needed to treat value (to prevent one cardiovascular event over 4.9 years compared with patients treated with atorvastatin 10 mg) for atorvastatin 80 mg was 29 for women and 30 for men. Rates of death of non-cardiovascular origin in the atorvastatin 80 mg and atorvastatin 10 mg were 3.6% and 1.6%, respectively (p = 0.004) among women, and 2.8% and 3.1% (p = 0.47) among men.

CONCLUSION

Intensive lipid-lowering treatment with atorvastatin 80 mg produced significant reductions in relative risk for major cardiovascular events compared with atorvastatin 10 mg in both women and men with stable CHD.

Measurement of global haemostasis in severe haemophilia A following factor VIII infusion

Patients with haemophilia requires different amounts of FVIII to prevent and treat bleeds. We hypothesise that this is because FVIII has variable effects on individual patients' global haemostasis. Twelve patients with severe haemophilia A were infused with 50 IU/kg FVIII and thrombin generation in platelet rich (PRP) and platelet poor plasma (PPP) and velocity of changing clot elasticity were measured preinfusion and at nine subsequent time points over 72 h. Despite a close correlation between median FVIII and median initial rate of thrombin generation (R(2) 0.94), endogenous thrombin potential (ETP; R(2) 0.94) and peak thrombin (R(2) 0.91) in PPP, there was wide inter-patient variability at each time point. There was, however, a highly predictable intra-patient relationship between FVIII level and thrombin generation. Inter-patient variability was due to both differences in FVIII levels and the variable effect FVIII had on an individuals' thrombin generation. The utility of PRP was limited because, at low-FVIII levels, only rate of thrombin generation was measurable. At low-FVIII concentrations, the rate of thrombin generation in PPP was the most useful test whilst at higher levels ETP and peak thrombin could also be used.

Pre-operative oral iron supplementation reduces blood transfusion in colorectal surgery - a prospective, randomised, controlled trial

INTRODUCTION

Allogeneic blood transfusion confers a risk to the recipient. Recent trials in colorectal surgery have shown that the most significant factors predicting blood transfusion are pre-operative haemoglobin, operative blood loss and presence of a transfusion protocol. We report a randomised, controlled trial of oral ferrous sulphate 200 mg TDS for 2 weeks' pre-operatively versus no iron therapy.

PATIENTS AND METHODS

Patients diagnosed with colorectal cancer were recruited from out-patient clinic and haematological parameters assessed. Randomisation was co-ordinated via a telephone randomisation centre.

RESULTS

Of the 49 patients recruited, 45 underwent colorectal resection. There were no differences between those patients not receiving iron (n = 23) and the iron-supplemented group (n = 22) for haemoglobin at recruitment, operative blood loss, operation duration or length of hospital stay. At admission to hospital, the iron-supplemented group had a higher haemoglobin than the non-iron treated group (mean haemoglobin concentration 13.1 g/dl [range, 9.6-17 g/dl] versus 11.8 g/dl [range, 7.8-14.7 g/dl]; P = 0.040; 95% CI 0.26-0.97) and were less likely to require operative blood transfusion (mean 0 U [range, 0-4 U] versus 2 U [range, 0-11 U] transfused; P = 0.031; 95% CI 0.13-2.59). This represented a cost reduction of 66% (47 U of blood = pound4700 versus oral FeSO(4) at pound30 + 15 U blood at pound1500). At admission, ferritin in the iron-treated group had risen significantly from 40 microg/l (range, 15-222 microg/l) to 73 microg/l (range, 27-386 microg/l; P = 0.0036; 95% CI 46.53-10.57).

CONCLUSIONS

Oral ferrous sulphate given pre-operatively in patients undergoing colorectal surgery offers a simple, inexpensive method of reducing blood transfusions.

5-HT activates vagal afferent cell bodies in vivo: Role of 5-HT2 and 5-HT3 receptors

Occipital artery (OA) injections of 5-HT elicit pronounced reductions in heart rate and mean arterial blood pressure (MAP) in urethane-anesthetized rats by activation of vagal afferent cell bodies in the ipsilateral nodose ganglion. In contrast, internal carotid artery (ICA) and i.v. injections elicit similar cardiovascular responses by activation of peripheral vagal afferent terminals. The aim of this study was to examine the roles of 5-HT3 and 5-HT2 receptors in the 5-HT-induced activation of vagal afferent cell bodies and peripheral afferent terminals in urethane-anesthetized rats. OA, ICA and i.v. injections of 5-HT elicited dose-dependent reductions in heart rate and MAP that were virtually abolished after i.v. administration of the 5-HT3 receptor antagonists, MDL 7222 or ICS 205-930. The responses elicited by the OA injections of 5-HT were markedly diminished after i.v. injection of the 5-HT2 receptor antagonists, xylamidine or ketanserin, whereas the responses elicited by i.v. or ICA injections of 5-HT were not affected. The present findings suggest that (1) 5-HT3 and 5-HT2 receptor antagonists gain ready access to nodose ganglion cells upon i.v. administration, and (2) functional 5-HT3 and 5-HT2 receptors exist on the cell bodies of vagal afferent neurons mediating the cardiovascular responses elicited by OA injections of 5-HT. These findings also support a wealth of evidence that 5-HT3 receptors exist on the peripheral terminals of vagal afferents, and although they do not discount the possibility that 5-HT2 receptors exist on peripheral vagal afferent terminals, it appears that activation of these receptors does not have pronounced effects on 5-HT3 receptor activity on terminals that mediate the hemodynamic responses to 5-HT.

Early enteral nutrition within 24h of colorectal surgery versus later commencement of feeding for postoperative complications

BACKGROUND

The role of early postoperative enteral nutrition after gastrointestinal surgery is controversial. Traditional management consist of 'nil by mouth', where patients receive fluids followed by solids when tolerated. Although several trials have implicated lower incidence of septic complications and faster wound healing upon early enteral feeding, other trials have shown opposite results. The immediate advantage of caloric intake could be a faster recovery with fewer complications, to be evaluated systematically.

OBJECTIVES

To evaluate whether early commencement of postoperative enteral nutrition compared to traditional management (no nutritional supply) is associated with fewer complications in patients undergoing gastrointestinal surgery

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, PUBMED, EMBASE, and LILACS from 1979 (first RCT published) to March 2006. We manually scanned the references from the relevant articles, and consulted primary authors for additional information.

SELECTION CRITERIA

We looked for randomised controlled trials (RCT's) comparing early commencement of feeding (within 24 hours) with no feeding in patients undergoing gastrointestinal surgery. Early enteral nutrition is defined as all oral intakes (i.e. registered oral intake, supplemented oral feeding) and any kind of tube feeding (gastric, duodenal or jejunal) containing caloric content. No feeding is traditional management, defined as none caloric oral intake or any kind of tube feeding before bowel function. The definition 'no nutrition' includes non caloric placebo and water.

DATA COLLECTION AND ANALYSIS

The three authors independently assessed the identified trials, and extracted the relevant data using a specifically developed data extraction sheet. Primary end points of interest were: Wound infections and intraabdominal abscesses, postoperative complications such as acute myocardial infarction, postoperative thrombosis or pneumonia, anastomotic leakages, mortality, length of hospital stay, and significant adverse effects. We combined data to estimate the common relative risk of postoperative complications, and calculated the associated 95% confidence intervals. For analysis, we used fixed effects model (risk ratios to summarise the treatment effect) whenever feasible. The treatment effect on length of stay was estimated using effect size (presented as mean +/- SD). Some outcomes were not analysed but presented in a descriptive way. We used a random effects model to estimate overall risk ratio and effect size.

MAIN RESULTS

We identified thirteen randomised controlled trials, with a total of 1173 patients, all undergoing gastrointestinal surgery. Individual clinical complications failed to reach statistical significance, but the direction of effect indicates that earlier feeding may reduce the risk of post surgical complications. Mortality was the only outcome showing a significant benefit, but not necessarily associated with early commencement of feeding, as the reported cause of death was anastomotic leakage, reoperation, and acute myocardial infarction.

AUTHORS' CONCLUSIONS

Although non-significant results, there is no obvious advantage in keeping patients 'nil by mouth' following gastrointestinal surgery, and this review support the notion on early commencement of enteral feeding.

Occipital artery injections of 5-HT may directly activate the cell bodies of vagal and glossopharyngeal afferent cell bodies in the rat

The primary objective of this study was to determine whether circulating factors gain direct access to and affect the activity of vagal afferent cell bodies in the nodose ganglia and glossopharyngeal afferents cell bodies in the petrosal ganglia, of the rat. We found that the occipital and internal carotid arteries provided the sole blood supply to the nodose ganglia, and that i.v. injections of the tracer, Basic Blue 9, elicited strong cytoplasmic staining in vagal and glossopharyngeal afferent cell bodies that was prevented by prior ligation of the occipital but not the internal carotid arteries. We also found that occipital artery injections of 5-HT elicited pronounced dose-dependent reductions in heart rate and diastolic arterial blood pressure that were (1) virtually abolished after application of the local anesthetic, procaine, to the ipsilateral nodose and petrosal ganglia, (2) markedly attenuated after transection of the ipsilateral vagus between the nodose ganglion and brain and virtually abolished after subsequent transection of the ipsilateral glossopharyngeal nerve between the petrosal ganglion and the brain, (3) augmented after ipsilateral transection of the aortic depressor and carotid sinus nerves, and (4) augmented after transection of all ipsilateral glossopharyngeal and vagal afferent nerves except for vagal cardiopulmonary afferents. These findings suggest that blood-borne 5-HT in the occipital artery gains direct access to and activates the cell bodies of vagal cardiopulmonary afferents of the rat and glossopharyngeal afferents of undetermined modalities.

An investigation into the current peri-operative nutritional management of oesophageal carcinoma patients in major carcinoma centres in England

INTRODUCTION

Patients with oesophageal carcinoma are at high risk of malnutrition. The aim of this study was to assess current practice for the nutritional management of patients following surgery for oesophageal carcinoma.

PATIENTS AND METHODS

A postal questionnaire was sent to 82 dietetic departments of those hospitals in England identified as major centres for upper gastrointestinal surgery.

RESULTS

Of the 66 (80%) responses received, 22 (33%) centres routinely perform pre-operative nutritional screening/assessment on oesophageal carcinoma patients. Centres with dietetic support dedicated to these patients are more likely to perform a pre-operative nutritional assessment (n = 17; 55%) than those without (n = 5; 14%; P < 0.001; chi(2) = 12.17). Pre-operative nutritional support is routinely provided in only 11 (17%) centres with the majority of centres (n = 50; 75%), providing it if patients are considered malnourished only. A total of 47 (70%) centres routinely provide postoperative nutritional support with jejunal feeding being the most commonly chosen route. Dedicated dietetic support is provided at 31 (47%) centres. Those centres with a dedicated dietitian are more likely to provide early postoperative nutritional support (n = 27; 87%) than those without (n = 20; 57%; P = 0.007; chi(2) = 7.195) and more likely to review patients routinely following discharge from hospital (n = 25 [81%] with a dietitian versus n = 17 [49%] without; P = 0.007; chi(2) = 7.2).

CONCLUSIONS

The nutritional management of patients following surgery for upper gastrointestinal carcinoma is not uniform with practice varying considerably between centres. Those centres with a dedicated dietitian are more likely to assess patients' nutritional status and provide nutritional support.

The thermolabile variant of MTHFR is associated with depression in the British Women's Heart and Health Study and a meta-analysis

Low dietary folate intake has been implicated as a risk factor for depression. However, observational epidemiological studies are plagued by problems of confounding, reverse causality and measurement error. A common polymorphism (C677T) in MTHFR is associated with methyltetrahydrofolate reductase (MTHFR) activity and circulating folate and homocysteine levels and offers insights into whether the association between low folate and depression is causal. We genotyped this polymorphism in 3,478 women in the British Women's Heart and Health Study. In these women, we looked at the association between genotype and three indicators of depression; ever diagnosed as depressed, currently taking antidepressants and the EuroQol mood question. We also carried out a systematic review and meta-analysis of all published studies which have looked at the association between MTHFR C677T genotype and depression. In the British Women's Heart and Health Study, we found evidence of an increased risk of ever being diagnosed as depressed in MTHFR C677T TT individuals compared with CC individuals, odds ratio (OR) 1.35(95% CI: 1.01, 1.80). Furthermore, we identified eight other studies, which have examined the association between depression and MTHFR C677T. We were able to include all of these studies in our meta-analysis together with our results, obtaining an overall summary OR of 1.36 (95% CI: 1.11, 1.67, P=0.003). Since this genotype influences the functioning of the folate metabolic pathway, these findings suggest that folate or its derivatives may be causally related to risk of depression.

Meta-analysis of vitamin D receptor polymorphisms and pulmonary tuberculosis risk

Several case-control studies performed in populations where the incidence of tuberculosis (TB) is high have examined genetic susceptibility to TB. The Vitamin D receptor (VDR) gene is a good candidate, because it influences immune response, and associations between TaqI and FokI polymorphisms in the VDR gene and pulmonary TB risk have been found. Furthermore, if a relationship between these polymorphisms and TB risk is confirmed this will be important evidence pointing to vitamin D as a potential preventive agent for TB. We carried out a systematic review and meta-analysis, and found that results were inconclusive and studies were underpowered.

A double-blind placebo-controlled study of the effects of Lactobacillus acidophilus on plasma lipids

OBJECTIVE

To select a probiotic bacteria that would reduce serum lipids in hypercholesterolaemic volunteers.

DESIGN

A strain of lactobacillus was selected for its ability to metabolise cholesterol under varying conditions in vitro. Freeze-dried Lactobacillus acidophilus or placebo were then given in a double-blind randomised crossover study to volunteers with high cholesterols.

SUBJECTS

A total of 80 volunteers with elevated cholesterols.

INTERVENTIONS

Volunteers were randomly allocated to receive either two capsules containing freeze-dried L. acidophilus 3 x 10(10) CFU or placebo three times a day for 6 weeks. After a 6-week washout period, volunteers were crossed over to another 6 weeks of capsules. Serum lipids were measured at the beginning and end of each interventional period.

RESULTS

L. acidophilus was able to reduce cholesterol and survive in an acid and bile environment. No changes in anthropomorphic measurements or in dietary records were seen between the baseline and final records or between the two sets of baseline records. There were no changes in serum lipids seen throughout the study.

CONCLUSION

Despite the ability in vitro for L. acidophilus to reduce cholesterol, no effect was seen in volunteers.

Retrospective study of Old World screwworm fly (Chrysomya bezziana) myiasis in 59 dogs in Hong Kong over a one year period

This retrospective study examined the case records of Old World screw-worm fly myiasis in dogs in Hong Kong's New Territories. Myiasis due to OWSWF was identified and treated in 59 dogs at our clinic over a period of 1 year. Signalment, causes of initial wound, and treatments implemented, are reported. All cases recovered from myiasis with a combination of larvae removal and wound debridement, antibiotics, and topical and systemic insecticides. Whilst this parasite is currently exotic to Australia, much of the country is environmentally suitable (tropical and subtropical) for establishment of OWSWF.

Wound healing and angiogenic properties of supernatants from Lactobacillus cultures

Extracts or supernatants from cultures of Lactobacilli are used for their medicinal effects, including wound healing and immune system stimulating activity. We have studied the in vivo and in vitro effects of supernatants from bacterial cultures of two strains of Lactobacillus (LS) on tissue repair and angiogenesis. Subcutaneous injection of LS into rodent ears led to proliferation of blood vessels that also exhibited strong immunostaining for Flk-1 receptor. Some inflammatory cells were scattered among the blood vessels. The continuous influx of polymorphonuclear leukocytes (PMNs) and macrophages into transcutaneous wounds in mice treated with LS resulted in prolonged inflammatory phase of wound healing and delayed wound closure, including reepithelialization. Subcutaneous injection of Matrigel impregnated with LS into the abdominal wall led to rapid and transient influx of PMNs in the vicinity of the gel. LS stimulated the proliferation of murine macrophage J774.A1 cell line and porcine lymphocytes but not that of murine fibroblast AKR-2B cells. LS also induced production of TNF-alpha by J774.A1 cells and by porcine kidney epithelial LLC-PK1 cells. LS did not appear to have an effect on collagen production. In conclusion, our study demonstrates the potential of LS to function as a stimulator of the inflammatory stage of tissue repair, TNF-alpha production, and of angiogenesis.

Migration and health impact assessment

Government policies, programmes and projects can have a significant impact on health. Health impact assessments (HIAs) seek to estimate this impact, but they often do so by measuring intermediate or proxy indicators and factors that act to determine health. These measures frequently assume a static population. However, regeneration policies can work hard for several years to no apparent effect. One explanation could be migration. Families who have benefited move from the area and other, perhaps more deprived, families move in. Conversely, healthy, prosperous families may move into an improved area, giving the impression that the health of the population has changed, when in fact it is the actual population that has changed. Census data in England and Wales show that a positive correlation exists between migration within wards and deprivation scores. This paper explores the possible implications of migration for HIA. The census, NHS central register, electoral register, labour force survey, central index of the Department of Social Security, council tax database and other data sources are examined to identify what migration data are available at a local level. Factors that determine rates of migration at a local level have been reviewed, with special reference to the differences between population subgroups. The paper concludes with recommendations to take account of residential mobility and changes in migration patterns when carrying out HIAs.

Dietary supplements of soya flour lower serum testosterone concentrations and improve markers of oxidative stress in men

OBJECTIVE

We examined the effects on serum sex steroids, lipids and markers of oxidative stress of supplementing the diets of healthy male volunteers with scones made with soya flour.

DESIGN

A randomized placebo controlled cross-over trial.

SETTING

University Hospital of Wales.

SUBJECTS

Twenty volunteers recruited by advertisement.

INTERVENTIONS

Male volunteers ate three scones a day in addition to their normal diet for a period of 6 weeks. The scones were made with either wheat or soya flour (containing 120 mg/day of isoflavones). Blood was analysed for sex steroids (testosterone, dihydro-testosterone, oestradiol, oestrone, sex hormone binding globulin, albumin and the concentration of non-protein bound sex steroids were calculated), lipid profile (total cholesterol, high density lipoprotein cholesterol and triglycerides) and measures of oxidative stress (hydroperoxides, susceptibility of LDL to oxidation with copper and myeloperoxidase).

RESULTS

The volunteers' mean age was 35.6 (s.d. 11.2) y. Total serum testosterone fell in volunteers taking the soya scones (19.3-18.2 nmol/l; 95% CI 1.01, 1.12; P=0.03). No significant changes were seen in the concentrations of the other serum sex steroids, albumin or sex hormone binding globulin throughout the study. Significant improvements in two of the three markers of oxidative stress were seen in volunteers taking soya scones. Lag time for myeloperoxidase rose from 55.0 to 68.0 min (95% CI -16.0, -3.5; P=0.009) and the presence of hydroperoxides decreased from 2.69 to 2.34 micro mol/l (95% CI 0.12, 0.71; P=0.009). There were no changes seen in serum triglycerides or cholesterol.

CONCLUSIONS

We have shown that soya supplements reduce serum testosterone and improve markers of oxidative stress. These findings provide a putative mechanism by which soya supplements could protect against prostatic disease and atherosclerosis. Further dietary studies with clinical end points are warranted.

Effect of electron beam irradiation on poultry meat safety and quality

The purpose of this study was to determine the effectiveness of electron beam irradiation at doses of 1.0 and 1.8 kGy on the elimination of bacteria from boneless, skinless chicken breasts without significantly altering product quality. Microbial testing was conducted in triplicate using a whole carcass rinse method with each nonirradiated control group and an irradiation treatment group consisting of 10 samples. Results indicated that mean counts for coliforms, generic Escherichia coli, and psychrotrophs were 3.13, 3.26, and 1.92 log10 cfu/200 mL rinsate, respectively, in the control samples. However, these populations were not detected after the samples were irradiated with 1.0 or 1.8 kGy. Mean count of 4.60 log10 cfu/200 mL rinsate was detected for aerobic bacteria in the control samples. Irradiation doses of 1.0 and 1.8 kGy reduced the levels to 2.23 and 1.62 log10 cfu/200 mL rinsate, respectively. Irradiation also rendered the fillets free of Salmonella and Campylobacter. Consumer taste panels (product stored for 0, 14, and 28 d at 0 C) indicated that, at Day 0, there were no differences among controls and treatment groups for any of the quality attributes tested. At Day 14, texture and flavor attributes were lower for the irradiated groups. At Day 28, samples irradiated with 1.0 and 1.8 kGy were less desirable with decreased texture, flavor, and overall acceptability. Degree of lipid oxidation also increased as storage time and level of irradiation increased. Irradiated samples also had higher a* values, indicating they were pinker in color.

Is electronystagmography of diagnostic value in the elderly?

We aimed to determine the diagnostic value of electronystagmography (ENG) in a community-based sample of dizzy subjects over 65 years old. A total of 96 asymptomatic controls and 149 dizzy subjects underwent ENG. Clinical diagnoses were made on standardized criteria. ENG results were classed as normal or abnormal, according to reference ranges derived from the controls. Rates of ENG abnormality in different diagnostic categories, sensitivities, specificities and predictive values were calculated. Central vascular disease was common (105 out of 149 subjects); peripheral vestibular disease was not (14). Spontaneous nystagmus had a positive predictive value of 95% for central vascular disease, but was only 18%-sensitive, and was usually detectable clinically. ENG had no other significant diagnostic value. ENG failed to discriminate dizzy subjects from controls and failed to differentiate various dizziness syndromes. ENG was of no practical value in this community-derived sample of dizzy elderly subjects.

Triggered electromyographic threshold for accuracy of thoracic pedicle screw placement in a porcine model

STUDY DESIGN

A porcine model of thoracic pedicle screw insertion was used to determine the effect of screw position on triggered electromyographic response.

OBJECTIVE

To develop a model of intraoperative detection of misplaced thoracic pedicle screws.

SUMMARY OF BACKGROUND DATA

Triggered electromyographic stimulation has been a valuable aid in determining appropriate placement of lumbar pedicle screws. The use of pedicle screws is increasing in the thoracic spine. Misplaced thoracic pedicle screws may have significant implications if the spinal cord is injured. This study was an attempt to determine whether the established lumbar model can be used for thoracic pedicle screws.

METHODS

Five 120- to 150-lb domestic pigs had 85 pedicle screws placed bilaterally in the thoracic spine at each level from T6 to T15. Screws were inserted entirely in the pedicle (Group A). After removal of the medial pedicle wall, the screws were reinserted in the pedicle with no neural contact (Group B). The screws were then placed with purposeful contact with the neural elements (Group C). The screws were stimulated, eliciting an electromyographic response in the intercostal muscles for each instrumented level. The type of response noted was classified as either primary (response from appropriate nerve root), secondary (response at different root) or no response (response at different root, no response at appropriate root).

RESULTS

Two hundred fifty responses were recorded. A primary response was noted in 72% of recordings. There was a relatively consistent decrease in the triggered electromyographic response from Group A (mean 4.15 +/- 1.80 mA) to Group C (mean 3.02 +/- 2.53 mA) screws (P = 0.0003). There was little difference in the response obtained from Group A to Group B (mean 4.37 +/- 2.48 mA) screws (P > 0.05). When a primary response was recorded, the mean threshold electromyographic response recorded was significantly lower than recordings with secondary and no response recordings (P < 0.05).

CONCLUSION

Even though there was a consistent decrease between the A and C screws that was more definitively separated when a primary response was elicited, it was not possible to determine a cutoff trigger electromyographic level that would consistently differentiate intraosseous from epidural pedicle screw placement. Furthermore, this method could not differentiate screws clearly in the pedicle from screws with medial pedicle wall breakthrough. A more direct method of spinal cord monitoring must be established to provide the surgeon with early warning of the potential of neural injury in the placement of thoracic pedicle screws.

Polymorphisms in the NAD(P)H: quinone oxidoreductase gene and small cell lung cancer risk in a UK population

NAD(P)H: quinone oxidoreductase (NQO1) protects the cell against cytotoxicity by reducing the concentration of free quinone available for single electron reduction. The NQO1 gene is polymorphic and the variant protein exhibits just 2% of the enzymatic activity of the wildtype protein. In this study, we investigated NQO1 genotype in relation to lung cancer risk in patients attending a Manchester bronchoscopy clinic. The cases were patients with a current, or history of, malignant tumour of the lung, trachea or bronchus. The control group were all other patients attending the clinic who had never been diagnosed with a tumour. DNA extraction from bronchial lavage or blood samples and genotyping was successfully carried out for 82 of the cases and 145 controls. Patients carrying at least one variant allele were found to have almost a 4-fold increased risk of developing small cell lung cancer (adjusted OR=3.80, 95% C.I. 1.19-12.1). No association between NQO1 genotypes and non-small cell lung cancer risk was found. Furthermore, the excess small cell lung cancer risk associated with non-wildtype NQO1 genotypes was only apparent in heavy smokers where there was a >10-fold increased risk (adjusted OR=12.5, 95% C.I. 2.1-75.5). These results suggest that the NQO1 protein may be involved in the detoxification of those carcinogens associated with the development of small cell lung cancer. Individuals with reduced enzyme activity, due to a polymorphism in this gene, may therefore have an increased risk of developing this disease.

Early enteral feeding versus "nil by mouth" after gastrointestinal surgery: systematic review and meta-analysis of controlled trials

OBJECTIVE

To determine whether a period of starvation (nil by mouth) after gastrointestinal surgery is beneficial in terms of specific outcomes.

DESIGN

Systematic review and meta-analysis of randomised controlled trials comparing any type of enteral feeding started within 24 hours after surgery with nil by mouth management in elective gastrointestinal surgery. Three electronic databases (PubMed, Embase, and the Cochrane controlled trials register) were searched, reference lists checked, and letters requesting details of unpublished trials and data sent to pharmaceutical companies and authors of previous trials.

MAIN OUTCOME MEASURES

Anastomotic dehiscence, infection of any type, wound infection, pneumonia, intra-abdominal abscess, length of hospital stay, and mortality.

RESULTS

Eleven studies with 837 patients met the inclusion criteria. In six studies patients in the intervention group were fed directly into the small bowel and in five studies patients were fed orally. Early feeding reduced the risk of any type of infection (relative risk 0.72, 95% confidence interval 0.54 to 0.98, P=0.036) and the mean length of stay in hospital (number of days reduced by 0.84, 0.36 to 1.33, P=0.001). Risk reductions were also seen for anastomotic dehiscence (0.53, 0.26 to 1.08, P=0.080), wound infection, pneumonia, intra-abdominal abscess, and mortality, but these failed to reach significance (P>0.10). The risk of vomiting was increased among patients fed early (1.27, 1.01 to 1.61, P=0.046).

CONCLUSIONS

There seems to be no clear advantage to keeping patients nil by mouth after elective gastrointestinal resection. Early feeding may be of benefit. An adequately powered trial is required to confirm or refute the benefits seen in small trials.

Minimum 2-year analysis of sacropelvic fixation and L5-S1 fusion using S1 and iliac screws

STUDY DESIGN

An analysis of lumbosacral fusions for high-grade spondylolisthesis fusions with reduction and long fusions to the sacrum in ambulatory adults.

OBJECTIVE

To assess the clinical and radiographic results of lumbosacral fusions using bilateral S1 and iliac screws.

SUMMARY OF BACKGROUND DATA

S1 screws often fail with lumbosacral fusions, whereas L5-S1 pseudarthrosis is common in patients with deformity.

MATERIALS AND METHODS

A total of 81 patients (38 revision, 43 primary) with minimum 2-year follow-up (average, 4.2 years; range, 2.0-7.1 years) underwent L5-S1 fusion using S1 and iliac screws (158 screws). Forty-nine of 81 constructs (61%) included an anterior load-sharing/fixation device. Group 1 included isthmic spondylolisthesis (n = 42), whereas Group 2 included long fusions (> or =3 levels) to the sacrum (n = 39). In Group 2, 15 patients (Group 2A) were fused from L1, L2, or L3 to the sacrum (3-5 levels, average 3.3 levels) and 24 patients (Group 2B) were fused from the thoracic spine to the sacrum (6-17 levels, average 11.5 levels). Twelve patients had pseudarthrosis at L5-S1. A patient questionnaire was completed.

RESULTS

A total of 36 of the 38 revision patients had previous iliac crest harvesting, yet iliac screws were placed in 34 of 36 patients. Overall, 78 of 80 patients had iliac crest harvesting (one not attempted). None had loss of screw fixation or iliac crest fracture after harvesting. Four of the 81 patients (4.9%) had pseudarthrosis at L5-S1 after reconstruction. This included solid fusion in 10 of 12 patients presenting with L5-S1 pseudarthrosis. Fourteen percent of patients experienced some discomfort over the iliac screws; however, only one patient required screw removal.

CONCLUSIONS

Bilateral iliac screws coupled with bilateral S1 screws provide excellent distal fixation for lumbosacral fusions with a high fusion rate (95.1%) in high-grade spondylolisthesis and long fusions to the sacrum. Previous iliac crest harvesting does not prevent ipsilateral screw placement (34 of 36 patients) or additional iliac harvesting (78 of 80 patients).

String test measurement to assess the effect of spinal deformity correction on spinal canal length

STUDY DESIGN

Long cassette coronal and lateral radiographs before and after surgical correction were analyzed and string test measurements made by three observers in 55 surgical cases (13 surgical types).

OBJECTIVES

The purpose of the study was to assess the effect of various corrective maneuvers for spinal deformity on the spinal canal length.

SUMMARY OF BACKGROUND DATA

When perioperative neurologic deficit occurs, the surgeon removes implants because they are displaced into the spinal canal or the canal has been lengthened. It is important to know the effect certain constructs have on canal length because the ability of the spinal cord to adapt to canal lengthening is variable.

METHODS

On the coronal radiographs the concave, convex, midvertebral, and adjusted midvertebral line, and on the sagittal radiographs, the anterior and posterior vertebral body lines were measured. The adjusted coronal line was the assumed path of the spinal cord starting at the midportion of the vertebral body at the top and the bottom of the deformity and then in between, hugging the pedicles as closely as possible while staying inside the pedicles. Adjustments for magnification were made.

RESULTS

Anterior compression instrumentation without cages (n = 5) consistently shortened the spinal canal (mean delta -6.67 +/- 2.30 mm, P = 0.003), whereas instrumentation with cages (n = 13) lengthened the canal (mean delta 10.54 +/- 7.58 mm, P = 0.0003). Thoracic curves treated by posterior corrective forces (n = 14) demonstrated lengthening of the canal (mean delta 10.14 +/- 5.23 mm, P = 0.0001), large (n = 5) curves (81-140 degrees, mean delta 13.47 +/- 7.05 mm), and medium (n = 7) curves (50-80 degrees, mean delta 8.43 +/- 3.24 mm).

CONCLUSIONS

Many deformity correction maneuvers, although they do not directly include application of posterior or anterior distraction forces, do indirectly lengthen the spinal canal.

Effects of chronic lesions of the anteroventral region of the third ventricle on cardiac beta-adrenoceptor function in conscious rats

This study examined whether cardiac beta-adrenoceptor (beta-AR) function was altered in conscious rats with lesions surrounding the anteroventral third ventricle (AV3V). The findings were: (1) beta(1,2)-AR-mediated tachycardia was similar in sham and AV3V-lesion rats, (2) beta(3)- and/or atypical beta-AR-mediated tachycardia elicited by isoproterenol (10 microg/kg, i.v.; ISO) was diminished in AV3V-lesion rats treated with beta(1,2)-AR antagonists, but was not in similarly-treated sham-lesion rats, and (3) the tachycardia elicited by the membrane permeable cAMP-analogue, 8-(4-chlorophenylthiol)-cAMP (10 micromol/kg, i.v.), was similar in AV3V- and sham-lesion rats. The possibility that increased plasma sodium/osmolality in AV3V-lesion rats down-regulated cardiac beta(3)- and/or atypical beta-ARs, but not beta(1,2)-ARs or intracellular cAMP signaling is discussed.

Guidelines for adults on self-medication for the treatment of acute diarrhoea

Acute uncomplicated diarrhoea is commonly treated by self-medication. Guidelines for treatment exist, but are inconsistent, sometimes contradictory, and often owe more to dogma than evidence. An ad hoc multidisciplinary group has reviewed the literature to determine best practice. In general it is recognized that treatment of acute episodes relieves discomfort and social dysfunction. There is no evidence that it prolongs the illness. Self-medication in otherwise healthy adults is safe. Oral loperamide is the treatment of choice. Older anti-diarrhoeal drugs are also effective in the relief of symptoms but carry the risk of unwanted adverse effects. Oral rehydration solutions do not relieve diarrhoea, and confer no added benefit for adults who can maintain their fluid intake. Probiotic agents are, at present, limited in efficacy and availability. Antimicrobial drugs, available without prescription in some countries, are not generally appropriate for self-medication, except for travellers on the basis of medical advice prior to departure. Medical intervention is recommended for the management of acute diarrhoea in the frail, the elderly (> 75 years), persons with concurrent chronic disease, and children. Medical intervention is also required when there is no abatement of the symptoms after 48 h, or when there is evidence of deterioration such as dehydration, abdominal distension, or the onset of dysentery (pyrexia > 38.5 degrees C and/or bloody stools).

Soft tissue sarcomas involving the pelvis

BACKGROUND AND OBJECTIVES

Soft tissue sarcomas (STS) of the true pelvis are rare tumors and there is little information in the literature related to pelvic STS. The purposes of this review were to understand the anatomic extension of these tumors to better plan surgical treatment and to determine the outcome of these patients.

METHODS

Eighteen consecutive patients presenting between 1987 and 1995 with soft tissue sarcomas involving the true pelvis were retrospectively reviewed at minimum follow-up of 18 months. Cross-sectional imaging was reviewed for each patient to determine the anatomical location of the lesions.

RESULTS

The tumors were confined to the true pelvis in 4 patients, extended to the retroperitoneum in three cases, and extended to the thigh in 11 patients. Adjuvant radiation was administered to all but 2 patients who had received radiation to the region in the past and all patients underwent surgical resection (local resection in 13 patients and hindquarter amputation in 5 patients). Surgical resection had a high rate of morbidity and complications including positive resection margins in nine individuals. Of the 18 patients, 11 died at a mean time of 15.5 (2-58) months from surgery, 4 were alive with evidence of disease at a mean time of 44.3 (18-68) months, and 3 were alive with no evidence of disease at a mean time of 57 (43-71) months.

CONCLUSIONS

Soft tissue sarcoma of the pelvis is fortunately a rare disease with a high risk of local and systemic disease progression despite treatment with irradiation and surgical resection.

Effect of an enteric-release formulation of naloxone on intestinal transit in volunteers taking codeine

INTRODUCTION

Constipation is a common side-effect of opioid therapy; in addition to their analgesic effect, opioids reduce intestinal secretion and motility with an increase in whole-gut transit time. Naloxone, a specific opioid antagonist, reverses these effects but may also cause symptoms of opioid withdrawal in patients on long-term therapy.

AIM

To use an enteric-release formulation, designed to produce a topical effect in the gut, with minimum systemic effects.

METHODS

Naloxone 10 mg b.d. and codeine 30 mg b.d. were used with identical placebo capsules in four sets of studies; 12 male volunteers were given the drugs alone and in combination, with a control study involving double placebo, during each of four study periods. Whole-gut transit time was calculated and compared for each treatment period.

RESULTS

Naloxone, both alone and with codeine, significantly shortened the mean whole-gut transit time compared with the control period, respectively, from 53.1 to 42.1 h (P=0.005) and to 40.7 h (P=0.024). Urgency to defecate was reported by two volunteers on naloxone alone and by three on combination therapy.

CONCLUSIONS

The results show that the naloxone formulation counteracts the effect of codeine on intestinal transit, suggesting that it may have useful clinical applications.

Osteoporosis prevention in myasthenia gravis: a reminder

OBJECTIVES

Consensus guidelines for bone management of patients taking corticosteroids suggest two main interventions: Dual energy X-ray absorptiometry (DEXA) scanning in those taking prednisolone > or =7.5 mg daily for > or =6 months (repeated every 1-3 years as indicated). Bisphosphonate therapy for those taking prednisolone > or =15 mg daily for > or =6 months regardless of DEXA result, and also for patients with known or high risk of developing osteoporosis (including those aged >65 years).

MATERIAL AND METHODS

We audited adherence to these guidelines in all adults with myasthenia gravis (MG) attending our neurology service.

RESULTS

Of 80 patients with MG (47 male, mean age 63.3 years), 34 (43%) had received corticosteroids for > or =6 months. Eighteen were taking prednisolone > or =7.5 mg daily (mean dose 16.6 mg) yet only 4 of these (22%) had undergone DEXA scanning. Of the 13 patients meeting the guideline criteria to receive bisphosphonate therapy, this was prescribed to only 7 (54%). Two others were prescribed vitamin D, 2 a calcium supplement and 2 were receiving no prophylaxis.

CONCLUSION

In these MG patients the guidelines were followed in only a minority. Neurologists need greater awareness of the bone health consequences of prescribing long-term corticosteroids.