Guiding equitable prioritisation of COVID-19 vaccine distribution and strategic deployment in South Africa to enhance effectiveness and access to vulnerable communities and prevent waste

BACKGROUND

In South Africa (SA), >2.4 million cases of COVID‑19 and >72 000 deaths were recorded between March 2020 and 1 August 2021, affecting the country's 52 districts to various extents. SA has committed to a COVID‑19 vaccine roll-out in three phases, prioritising frontline workers, the elderly, people with comorbidities and essential workers. However, additional actions will be necessary to support efficient allocation and equitable access for vulnerable, access-constrained communities.

OBJECTIVES

To explore various determinants of disease severity, resurgence risk and accessibility in order to aid an equitable, effective vaccine roll-out for SA that would maximise COVID‑19 epidemic control by reducing the number of COVID‑19 transmissions and resultant deaths, while at the same time reducing the risk of vaccine wastage.

METHODS

For the 52 districts of SA, 26 COVID‑19 indicators such as hospital admissions, deaths in hospital and mobility were ranked and hierarchically clustered with cases to identify which indicators can be used as indicators for severity or resurgence risk. Districts were then ranked using the estimated COVID‑19 severity and resurgence risk to assist with prioritisation of vaccine roll-out. Urban and rural accessibility were also explored as factors that could limit vaccine roll-out in hard-to-reach communities.

RESULTS

Highly populated urban districts showed the most cases. Districts such as Buffalo City, City of Cape Town and Nelson Mandela Bay experienced very severe first and second waves of the pandemic. Districts with high mobility, population size and density were found to be at highest risk of resurgence. In terms of accessibility, we found that 47.2% of the population are within 5 km of a hospital with ≥50 beds, and this percentage ranged from 87.0% in City of Cape Town to 0% in Namakwa district.

CONCLUSIONS

The end goal is to provide equal distribution of vaccines proportional to district populations, which will provide fair protection. Districts with a high risk of resurgence and severity should be prioritised for vaccine roll-out, particularly the major metropolitan areas. We provide recommendations for allocations of different vaccine types for each district that consider levels of access, numbers of doses and cold-chain storage capability.

590 Influence of Hospital Characteristics on Patient Outcomes Following Cancer Surgery: An International, Mixed Methods Study Across 66 Countries

Aim

Early death after cancer surgery is higher in low- and middle-income settings, yet the impact of hospital characteristics on early postoperative outcomes following cancer surgery worldwide are unknown.

Method

A mixed-methods analysis was performed using data from the GlobalSurg 3 study, a multicentre, international prospective cohort study of patients who underwent surgery for breast, gastric or colorectal cancer. The primary outcomes were 30-day mortality and major complication rates. Hierarchical clustering identified distinct hospital characteristics to create a facility capacity framework. Adjusted outcomes were determined after accounting for patient characteristics and country-income group.

Results

Hospital-level data were available for 9685 patients across 238 hospitals. The facility capacity framework consisted of seven distinct hospital resources and processes: presence of CT scan, postoperative recovery area, critical care facilities, opioid analgesia availability, oncologist, pathology and radiotherapy services. While complication rates were similar across hospitals with varying facility capacities, hospitals with five or less capacities (116 hospitals, 2251 patients) had increased mortality (aOR 1.67, 95% CI 1.13-2.48; P = 0.010). After adjustment for case-mix and country income group, patients undergoing surgery for gastric and colorectal cancer in hospitals with reduced capacities had higher mortality (6.2 vs. 4.0%; P < 0.001), predominantly explained by limited capacity to rescue following the development of major complications (61.3 vs. 72.1%; P < 0.001).

Conclusions

Hospitals with certain system capacities achieve better outcomes following cancer surgery, independent of country-income group. For cancers amenable to surgical treatment, national cancer care plans should include both surgical capacity building and concurrent hospital facility development to maximise reductions in cancer-associated mortality.

1163 Genome-wide Association Study Reveals 55 Loci Associated with Gallstone Disease

Aim

Gallstones have a prevalence of 20-40% in European populations and cause significant morbidity. Gallstones form from cholesterol and calcium bilirubinate and knowledge of genetic determinants remains incomplete. A genome-wide association study (GWAS) was performed to identify determinants of gallstones.

Method

A GWAS of 16,356,211 single nucleotide polymorphisms (SNPs) for 28,627 cases and 348,373 controls of European ancestry in the UK Biobank was undertaken. A logistic regression with additive allelic dosage was performed (significance: P < 5*10-8). Functional annotation and linkage disequilibrium clumping were performed to reveal distinct loci. Lead SNPs were investigated by linear regression for association with plasma lipids, liver enzymes and blood count markers.

Results

55 lithogenic loci were identified of which 27 are novel. Functional annotation revealed genes involved in metabolism of cholesterol, glucose, bile acids and bilirubin with corresponding changes in serum biomarkers caused by those lithogenic alleles. Several novel variants did not alter cholesterol or other biomarkers. Lithogenic variants within genes controlling intra- and paracellular transport may govern biliary composition (PCDHB4, NUP153, CLDN7) and promote lithogenic bile. Variants within genes which may influence gallbladder motility (ANO1, TMEM147) and cholangiocyte ciliogenesis (TBC1D32, ADAMTS20, DYNC2LI1, HNF1B) may promote gallstone formation through reduced biliary flow.

Conclusions

We identified 27 novel associations with gallstones. Impact of lithogenic alleles on serum biomarkers was highly variable demonstrating that gallstone formation is partially driven by pathways which do not influence cholesterol, glucose or bilirubin metabolism. Variants within genes that may influence biliary composition, bile flow and gallbladder motility represent new targets for research into gallstones.

427 The Effect of Malnutrition on Early Outcomes after Cancer Surgery: An International Prospective Cohort Study in 82 Countries

Background

Malnutrition is a state linked to worse postoperative outcomes, and cancer patients are particularly vulnerable due to cachexia. We aimed to explore the effect of malnutrition on 30-day mortality following gastric and colorectal cancer surgery.

Method

GlobalSurg3 was multicentre international cohort study which collected data from consecutive patients undergoing emergency or elective surgery for gastric and colorectal cancer. Malnutrition was defined using the Global Leadership Initiative on Malnutrition (GLIM) criteria. Multilevel variable regression approaches determined the relationship between malnutrition and early postoperative outcomes.

Results

6438 patients were included in the final analysis (1184 gastric cancer; 5254 colorectal cancer). Severe malnutrition was common across all income-strata, affecting 1 in 4 patients overall, with a higher burden in low and lower-middle income countries (64%). In patients undergoing elective surgery (n = 5709), severe malnutrition was independently associated with increased mortality (aOR = 1.62 (1.07-2.48, P = 0.024) after accounting for patient factors, disease stage and country effects.

Conclusions

Severe malnutrition represents a high global burden in cancer surgery, particularly within lower income settings. Malnutrition is an independent risk-factor for 30-day mortality following elective surgery for gastric and colorectal cancer, suggesting perioperative nutritional interventions may improve outcomes after cancer surgery.

O45: DEFINING CELL-ENRICHED MICRORNAS TO SUPPORT RATIONAL BIOMARKER SELECTION IN HUMAN RENAL TRANSPLANTATION

Introduction

MicroRNAs are promising biomarkers of renal disease, however the cellular origin of their expression is usually unclear limiting their interpretation when measured in renal biopsies and urine. We hypothesised that by first defining renal cell-enriched microRNAs, we could select biomarkers based on the expected histopathological profile.

Method

Small RNA-sequencing of cortical, proximal tubular (LTL), macrophage (F480), endothelial (CD31) and fibroblast (PDGFRb) populations from the reversible unilateral ureteric obstruction (rUUO) murine model was performed. Hierarchical clustering was used to identify clusters. Findings were translated into an ischaemia reperfusion injury (IRI) model and then into urine samples from renal transplant recipients (n=16) with delayed graft function (DGF) vs. those with primary function.

Result

Kidney injury resulted in significant macrophage infiltration and tubular injury which improved upon reversal. We characterised novel microRNA clusters enriched for each cell type. With injury there was a significant increase in macrophage (p<0.0001), fibroblast (p<0.01) and decrease in proximal tubule (p<0.0001) enriched microRNAs vs. non-enriched microRNAs. We validated macrophage enriched miR-18a, miR-16 and tubular enriched miR-194 in the IRI model, demonstrating that microRNA expression reflected the histological profile. In humans, urinary miR-16 (FC 16.9; p<0.05) and miR-18a (FC 10: p=0.06) were upregulated at day 2 in patients with DGF; outperforming the traditional injury marker KIM1.

Conclusion

This is the first study to characterise cell-enriched microRNAs during renal injury and repair. By defining the source of microRNA expression we were able to rationally select miR-16 and miR-18a as promising urinary biomarkers of renal injury.

Take-home message

We have found that microRNAs have differences in expression between cell types and renal injury states which is important when considering microRNA expression in samples composed of varying cellular composition. By defining the cellular origins of microRNA expression we were able to rationally select microRNA biomarkers of human renal injury.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

0840 Sleep Quality in Clinically Indicated In-Laboratory Polysomnography

Introduction

Few studies have explored how patients sleep or what characteristics might be predictive of poor sleep during clinically-indicated polysomnography (PSG) in an in-laboratory setting.

Methods

We reviewed clinically indicated diagnostic PSG studies completed over a 10-year period in a single academic sleep center. Total sleep time (TST) and sleep efficiency (SE) were used as proxies for sleep quality. Patients were categorized as normal or poor sleepers based on TST <4 hours or SE <50%. Multivariate linear and logistic regression analyses were performed to determine factors associated with sleep quality while controlling for demographics, medications, comorbidities and measures of sleep.

Results

We included 4957 patients, who were mostly female (58.9%), middle-aged (52.9 y), Caucasian (69.3%), and overweight or obese (91.3%). 3682 patients (74.2%) were diagnosed with sleep apnea (Apnea Hypopnea Index(AHI)>5/hr).

Average TST was 5.75±1.43 hours (Interquartile range [IQR] = 4.94 - 6.73) and average SE was 75.1%±16.1% (IQR=66.9 - 87.2). TST and SE were lower for males compared to females (5.48 vs 5.93 hr, p<0.001; 73% vs 77%, p<0.001). In multivariable analysis, older age (TST: OR = 1.04, 95% CI:[1.03,1.05]; SE: OR = 1.04, 95% CI:[1.04,1.05]), male sex (TST: 1.38,[1.14,1.68]; SE: 1.34,[1.07,1.68]), normal body habitus (TST: 1.47,[1.02,2.08]; SE: 1.51,[1.01,2.27]) and a higher AHI (TST: 1.02,[1.02,1.03]; SE: 1.02,[1.003,1.03]) were significantly associated with being a poor sleeper for both TST and SE. Antidepressant use was associated with poor sleep for TST (0.77, [0.59,1]), but not for SE (0.98, [0.73,1.3]).

Conclusion

Sleep quality during the in-laboratory PSG differed by sex, age and presence of sleep apnea. Sleep quality during in-lab PSG is thought to be compromised by obtrusive monitoring and an unfamiliar environment, but average sleep quality may be higher than expected for patients in the laboratory. Future studies should consider examining in-lab sleep quality in different patient populations.

Support

N/A

Management of cardiac disease in cancer patients throughout oncological treatment: ESMO consensus recommendations

Cancer and cardiovascular (CV) disease are the most prevalent diseases in the developed world. Evidence increasingly shows that these conditions are interlinked through common risk factors, coincident in an ageing population, and are connected biologically through some deleterious effects of anticancer treatment on CV health. Anticancer therapies can cause a wide spectrum of short- and long-term cardiotoxic effects. An explosion of novel cancer therapies has revolutionised this field and dramatically altered cancer prognosis. Nevertheless, these new therapies have introduced unexpected CV complications beyond heart failure. Common CV toxicities related to cancer therapy are defined, along with suggested strategies for prevention, detection and treatment. This ESMO consensus article proposes to define CV toxicities related to cancer or its therapies and provide guidance regarding prevention, screening, monitoring and treatment of CV toxicity. The majority of anticancer therapies are associated with some CV toxicity, ranging from asymptomatic and transient to more clinically significant and long-lasting cardiac events. It is critical however, that concerns about potential CV damage resulting from anticancer therapies should be weighed against the potential benefits of cancer therapy, including benefits in overall survival. CV disease in patients with cancer is complex and treatment needs to be individualised. The scope of cardio-oncology is wide and includes prevention, detection, monitoring and treatment of CV toxicity related to cancer therapy, and also ensuring the safe development of future novel cancer treatments that minimise the impact on CV health. It is anticipated that the management strategies discussed herein will be suitable for the majority of patients. Nonetheless, the clinical judgment of physicians remains extremely important; hence, when using these best clinical practices to inform treatment options and decisions, practitioners should also consider the individual circumstances of their patients on a case-by-case basis.

Female genital tract microbiota affecting the risk of preterm birth: What do we know so far? A review

Spontaneous Preterm birth (SPTB) is a common obstetric complication affecting 12.9 million births worldwide and is the leading cause of neonatal morbidity and mortality. Disruption in the vaginal microbiota has an impact on the maternal immunological profile leading to SPTBs. Scientists have struggled to link maternal infectious agents with the dysregulation of the maternal immune response in cases of SPTBs. Throughout the last decade, important findings regarding the role of microbiota and its genome, the so-called microbiome, have linked alterations within the population of the microorganisms in our bodies with changes in nutrition, immunity, behaviour and diseases. In this review, evidence regarding the female genital tract microbiota and microbiome has been examined to help further our understanding of its role in disrupting the maternal immune system resulting in spontaneous preterm birth.

Does functional outcome depend on the quality of the fracture fixation? Mid to long term outcomes of ankle fractures at two university teaching hospitals

BACKGROUND

The aim of our study was to assess the adequacy of reduction and internal fixation of ankle fractures and the long-term functional outcomes of patients treated in two university teaching hospitals by general orthopaedic surgeons.

METHOD

We performed a retrospective study involving two large trauma units in the UK, reviewing all operatively treated unstable ankle fractures performed in one centre between 1st October 2006 and 31st December 2007 and another centre between 1st January 2009 and 31st December 2009. All patients were contacted by postal follow up at a minimum of 6-years using the Olerud-Molander Ankle Score (OMAS).

RESULTS

261 patients underwent operative treatment for ankle fractures during the study period at the two hospitals. 107 patients responded to the questionnaire. Analysis of patients' functional outcome by fracture type reveals that the outcome scores decrease as the complexity of the ankle fracture increases. A significant finding within subgroup analysis found that trimalleolar fractures (B3) have worse outcomes than bimalleolar fractures (B2 and C); which in turn have worse outcomes than isolated lateral malleolar fractures (B1). Analyzing the outcome of patients based on the severity of malreduction revealed that Pettrone's value was inversely proportional to the OMAS.

CONCLUSION

We have found a significant reduction in patient reported function in patients whose fractures were malreduced at time of surgery.

Abstract 4947: Plucked anagen scalp hair: A comparison between different analytical techniques to establish reproducible drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from oncology patients

Plucked anagen scalp hair is an ideal surrogate tissue to monitor drug induced transcriptional changes. High vascularisation of the hair follicle, ease of sampling and high degree of similarity of expression in hair of pathways dysregulated in cancers, make the cellular bulb of plucked human scalp hair an excellent surrogate tissue for the non-invasive monitoring of pharmacodynamic (PD) and mechanism of action (MOA) effects in clinical trials. Using our ex vivo plucked hair culture platform, plucked scalp hair bulbs from several healthy donors were exposed to BEZ235, a dual pan-class PI3K and mTOR inhibitor at different concentrations and durations. Total RNA was isolated from the cellular bulb of anagen hair post-culture and samples were assessed by microarray and RNA-seq analysis to assess dose dependent global transcriptional alterations and develop a gene expression signature indicative of BEZ235 exposure. Two different microarrays, the Affymetrix Clariom D and U133 plus 2.0 arrays, were directly compared to RNA-seq data obtained from the same ex vivo culture samples. Genetic signatures indicative of exposure of plucked scalp hair to BEZ235 were established using all three analytical techniques. The transcriptional readouts from the plucked scalp hair samples revealed strong correlations (0.97-0.99) in the genes expressed in anagen scalp hair between donors. In addition, global gene expression data indicated that assessing pooled scalp hairs was sufficient to detect significant differential expression (p<0.05 & 1.5 fold change) underpinning the low variance in the majority of target genes in plucked hair as a biomarker platform. Gene signatures for compounds targeting the PI3K/mTOR pathway that were established using the ex vivo plucked scalp hair platform were subsequently used to support clinical trials and scalp hair taken from patients receiving treatment showed an excellent post-exposure target signature modulation. In summary, the results of the ex vivo plucked assessment generated a dose dependent and biologically relevant transcriptional signature following exposure to BEZ235. Plucked anagen scalp hair is therefore an ideal non-invasive surrogate tissue to obtain drug-induced pharmacodynamic biomarker and target engagement information from oncology patients.

Citation Format: Tim Mefo, Elliott Harrison, Alan Murdoch, Benjamin Reed. Plucked anagen scalp hair: A comparison between different analytical techniques to establish reproducible drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from oncology patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4947.

Household Food Security, Food Consumption Patterns, and the Quality of Children's Diet in a Rural Northern Ghana Community

Twenty households in a rural northern Ghana community were studied to ascertain evidence of seasonality and the relationship between household food-security status and the food and nutrient intakes of preschool children. All food consumed by household members was weighed for three consecutive days, and nutrient intakes were calculated from appropriate food composition tables. Diet quality was assessed by quantitative and descriptive analysis. Mean daily intakes of selected food items reflected an over-dependence on cereals and a minimal consumption of animal products. The consumption of vegetables, especially low during the pre-harvest season, increased during the post-harvest season. Nutrient intakes, which were generally lower than recommended dietary allowances, increased during the post-harvest season, although not significantly for calories, protein, and iron (p <.05), in contrast to vitamins A and C (p < .001). There was a significant association between household food-security status and the intakes of calories (p < .001) and protein (p < .01) but not of micronutrients. Diet quality was adversely influenced by a low intake of micronutrients derived primarily from plant sources as well as by poor dietary habits. Calorie and protein intakes appear to have been more influenced by household food availability and were subject to less seasonal fluctuation, while the reverse held true for the micronutrients. In addition, household food security did not necessarily ensure the quality of children's diets in an area where food consumption patterns are monotonous.

Development and clinical validation of the Genedrive point-of-care test for qualitative detection of hepatitis C virus

OBJECTIVE

Recently approved direct acting antivirals provide transformative therapies for chronic hepatitis C virus (HCV) infection. The major clinical challenge remains to identify the undiagnosed patients worldwide, many of whom live in low-income and middle-income countries, where access to nucleic acid testing remains limited. The aim of this study was to develop and validate a point-of-care (PoC) assay for the qualitative detection of HCV RNA.

DESIGN

We developed a PoC assay for the qualitative detection of HCV RNA on the PCR Genedrive instrument. We validated the Genedrive HCV assay through a case-control study comparing results with those obtained with the Abbott RealTime HCV test.

RESULTS

The PoC assay identified all major HCV genotypes, with a limit of detection of 2362 IU/mL (95% CI 1966 to 2788). Using 422 patients chronically infected with HCV and 503 controls negative for anti-HCV and HCV RNA, the Genedrive HCV assay showed 98.6% sensitivity (95% CI 96.9% to 99.5%) and 100% specificity (95% CI 99.3% to 100%) to detect HCV. In addition, melting peak ratiometric analysis demonstrated proof-of-principle for semiquantification of HCV. The test was further validated in a real clinical setting in a resource-limited country.

CONCLUSION

We report a rapid, simple, portable and accurate PoC molecular test for HCV, with sensitivity and specificity that fulfils the recent FIND/WHO Target Product Profile for HCV decentralised testing in low-income and middle-income countries. This Genedrive HCV assay may positively impact the continuum of HCV care from screening to cure by supporting real-time treatment decisions.

TRIAL REGISTRATION NUMBER

NCT02992184 .

Abstract 3830: Plucked anagen scalp hair: A reproducible surrogate tissue to monitor drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from cancer patients

Monitoring target engagement is crucial to inform on early drug development decisions, and development of a peripheral tissue-based gene expression signature indicative of pathway inhibition could facilitate the continued clinical development of compounds. Plucked anagen scalp hair is an ideal source of epithelial tissue to monitor drug induced transcriptional changes. High vascularisation of the hair follicle, frequent epithelial origin of tumors, ease of sampling and high degree of congruence of expression in hair of pathways dysregulated in cancers, make the cellular bulb of plucked human scalp hair an excellent surrogate tissue for the non-invasive monitoring of pharmacodynamic (PD) and mechanism of action (MOA) effects in clinical trials. Using our ex vivo plucked hair culture platform, hair bulbs from several healthy donors were exposed to BEZ235, a dual pan-class PI3K and mTOR inhibitor at different concentrations and durations. Total RNA was isolated from the cellular bulb of individual anagen hair post-culture and used for microarray analysis to assess global transcriptional alterations and develop a gene expression signature indicative of BEZ235 exposure. The results of the ex vivo plucked assessment generated a dose dependent appreciable and biologically relevant transcriptional signature following exposure to BEZ235. Transcriptional readouts from patients also revealed strong correlations (0.97-0.99) in the genes expressed in anagen scalp hair between donors and across samples taken from the same donor. In addition, global gene expression data indicated that assessing three plucked scalp hairs or less at each collection point was sufficient to detect significant differential expression (p&lt;0.05 & 1.5 fold change) underpinning the low variance in the majority of target genes in plucked hair as a biomarker platform. Gene signatures for compounds targeting the PI3K/mTOR pathway that were established using the ex vivo plucked scalp hair platform were used to support clinical trials and scalp hair taken from patients receiving treatment showed an excellent post-exposure target signature modulation. In summary, our results substantiate that plucked anagen scalp hair is an ideal non-invasive surrogate tissue to obtain drug-induced pharmacodynamic biomarker and target engagement information from oncology patients.

Citation Format: Benjamin J. Reed, Timothy Mefo, Elliott Harrison, Ross Haggart, Emma Grimes, Alan Murdoch, Gino Miele. Plucked anagen scalp hair: A reproducible surrogate tissue to monitor drug induced transcriptional changes and provide pharmacodynamic biomarker and target engagement information from cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3830. doi:10.1158/1538-7445.AM2017-3830

Abstract 1677: Immuno-target selection of infiltrating immune cells and laser capture microdissection mediated transcriptional profiling

Immune checkpoints define an evolving class of inhibitory mediators that are expressed by tumour cells and infiltrating leucocytes to down-modulate the effector immune response against tumour cells. Therefore, the most recent efforts in cancer therapy centre on targeting immune-mediated mechanisms of tumour evasion. The ability to assess gene expression profiles from isolated populations of tumour-infiltrating lymphocytes (TILs) can assist in monitoring checkpoint inhibitor therapy efficacy and provide a better understanding of clinical outcomes. Ideally, transcriptional profiles should be obtained from isolated cell populations of interest, free from contaminating cell populations that may create adverse background noise. Micro sampling by laser capture microdissection is a powerful tool that allows for specific analysis from whole tissues, particularly in a heterogeneous microenvironment such as in a tumour, where less well represented target cells are dwarfed in abundance by tissue stroma and other cell types. However, whilst the application is potentially powerful for target discovery and mechanistic understanding, the process is notoriously difficult, particularly in clinical specimens. We developed a methodology to successfully overcome these challenges in analysing target cells, organelles or other tissue subsets by transcriptional profiling following immunostain-mediated laser capture microscopy (LCM). Thorough optimisation of traditional immunohistochemistry techniques enabled us to select target cell populations of interest from tissue sections whilst minimising degradation of mRNA and miRNA allowing us to perform genomic and pathway interrogation using microarray and/or RT-qPCR analysis. Our technique allows multiple capture types per slide, sample pooling when required, high capture throughput and capture image documentation. Multiple target selection, to differentiate lymphocytes, can be performed routinely using comparative serial sectioning. Here we exhibit simple staining and immunostaining histology images using methods sympathetic to RNA integrity which allow for target selection by specific staining or target morphology, and demonstrate comparative analysis of matched pairs of disease and healthy sections of colon tumours. We used a Palm MicroBeam 4 LCM platform to identify, cut and specifically capture CD8+ tumour-infiltrating lymphocytes from frozen embedded tissue. This approach enabled us to isolate discrete targeted cell populations free from contaminating cell populations. Epistem’s Single Cell RNA-Amp™ was then used to provide robust and linear amplification of RNA and enable comparative analysis in applications such as target discovery and pharmacodynamics. The results indicated that transcriptional profiling was technically robust with a good replicate correlation despite the limited input obtained by micro-sampling.

Citation Format: Ross Haggart, Chaxiraxi Arzola-Donate, Elliott Harrison, Benjamin J. Reed, Saba Alzabin, Gino Miele. Immuno-target selection of infiltrating immune cells and laser capture microdissection mediated transcriptional profiling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1677. doi:10.1158/1538-7445.AM2017-1677

Abstract OT1-04-01: Cambridge brain mets trial 1 (CamBMT1): A proof-of-principle phase 1b / randomised phase 2 study of afatinib penetration into brain metastases for patients undergoing neurosurgical resection, both with and without prior low-dose, targeted radiotherapy

Background

Failure of drugs to cross the blood brain barrier (BBB) can be a major reason for treatment failure for patients with brain tumors. For most patients who don't respond to treatment, it is not known whether this is due to inadequate drug concentrations in the tumor, or due to drug resistance. Preliminary data suggest that low-dose radiotherapy may disrupt the BBB, and could facilitate increased drug delivery into brain tumors. Afatinib is a potent, irreversible inhibitor of EGFR / HER2 / HER4 and takes approximately 8 days to achieve steady-state concentrations in cancer patients.

Aims

CamBMT1 has been designed to investigate the delivery of afatinib into brain metastases and whether this might be enhanced by low dose-radiotherapy.

Patient Population

Key eligibility criteria

Patients with operable brain metastases from breast or lung primaries for whom neurosurgical resection would be standard of care, as determined by the local multi-disciplinary team. ECOG PS 0, 1 or 2.

Trial design

After a phase 1b safety run- in, the phase 2 part of the trial randomises patients (n=60) into 3 pre-operative arms:

Arm 1afatinib alone for 11 days, then neurosurgery on day 12Arm 2afatinib for 11 days plus a single 2 Gy fraction on day 10, then neurosurgery on day 12Arm 3afatinib for 11 days plus a single 4 Gy fraction on day 10, then neurosurgery on day 12

Primary endpoint: to compare steady-state afatinib concentration in resected brain metastases, following afatinib administered alone, or in combination with radiotherapy (2 Gy or 4 Gy). Afatinib concentrations are measured in the resected brain metastases and in plasma.

Secondary endpoints: safety of afatinib administration in combination with radiotherapy; and multi-sequence MRI (optional) to detect changes in perfusion, vascular density, blood-brain-barrier permeability and interstitial pressure.

Exploratory endpoints: molecular profiling of resected brain metastases, for comparison with paired primary lung and breast cancers; the establishment and study of patient-derived xenografts.

Statistical methods

With 20 patients randomised in each of 3 arms in the phase 2 part of CamBMT1, the trial has a power of 84% at a significance level of 20% (one-sided) to detect an increase in afatinib concentrations with targeted radiotherapy, measured as a Cohen's D (standardised mean difference) ≥0.5.

Accrual

By the end of q2 2016, phase 1b had nearly completed enrolment. The randomised phase 2 part of CamBMT1 is due to open by q4 2016 at additional Experimental Cancer Medicine Centres.

Acknowledgments

CamBMT1 is funded by Cancer Research UK, the Brain Tumour Charity and Boehringer-Ingelheim.

Citation Format: Baird RD, Ramenatte N, Watts C, Jonson A, Jones L, Biggs H, Harrison E, Oberg I, Bullen G, Williams M, Qian W, Gilbert F, Jodrell D, Caldas C, Karabatsou K, Dunn L, Jena R, Whitfield G, Chalmers A, Jefferies S, Price S. Cambridge brain mets trial 1 (CamBMT1): A proof-of-principle phase 1b / randomised phase 2 study of afatinib penetration into brain metastases for patients undergoing neurosurgical resection, both with and without prior low-dose, targeted radiotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-04-01.

Novel pH sensing semiconductor for point-of-care detection of HIV-1 viremia

The timely detection of viremia in HIV-infected patients receiving antiviral treatment is key to ensuring effective therapy and preventing the emergence of drug resistance. In high HIV burden settings, the cost and complexity of diagnostics limit their availability. We have developed a novel complementary metal-oxide semiconductor (CMOS) chip based, pH-mediated, point-of-care HIV-1 viral load monitoring assay that simultaneously amplifies and detects HIV-1 RNA. A novel low-buffer HIV-1 pH-LAMP (loop-mediated isothermal amplification) assay was optimised and incorporated into a pH sensitive CMOS chip. Screening of 991 clinical samples (164 on the chip) yielded a sensitivity of 95% (in vitro) and 88.8% (on-chip) at >1000 RNA copies/reaction across a broad spectrum of HIV-1 viral clades. Median time to detection was 20.8 minutes in samples with >1000 copies RNA. The sensitivity, specificity and reproducibility are close to that required to produce a point-of-care device which would be of benefit in resource poor regions, and could be performed on an USB stick or similar low power device.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Evaluation of recruitment methods for a trial targeting childhood obesity: Families for Health randomised controlled trial

BACKGROUND

Recruitment to trials evaluating the effectiveness of childhood obesity management interventions is challenging. We report our experience of recruitment to the Families for Health study, a randomised controlled trial evaluating the effectiveness of a family-based community programme for children aged 6-11 years, versus usual care. We evaluated the effectiveness of active recruitment (contacting eligible families directly) versus passive recruitment (informing the community through flyers, public events, media).

METHODS

Initial approaches included passive recruitment via the media (newspapers and radio) and two active recruitment methods: National Child Measurement Programme (letters to families with overweight children) and referrals from health-care professionals. With slow initial recruitment, further strategies were employed, including active (e.g. targeted letters from general practices) and passive (e.g. flyers, posters and public events) methods. At first enquiry from a potential participant, families were asked where they heard about the study. Further quantitative (questionnaire) and qualitative data (one-to-one interviews with parents/carers), were collected from recruited families at baseline and 3-month follow-up and included questions about recruitment.

RESULTS

In total, 194 families enquired about Families for Health, and 115 (59.3 %) were recruited and randomised. Active recruitment yielded 85 enquiries, with 43 families recruited (50.6 %); passive recruitment yielded 99 enquiries with 72 families recruited (72.7 %). Information seen at schools or GP surgeries accounted for over a quarter of enquiries (28.4 %) and over a third (37.4 %) of final recruitment. Eight out of ten families who enquired this way were recruited. Media-led enquiries were low (5 %), but all were recruited. Children of families recruited actively were more likely to be Asian or mixed race. Despite extensive recruitment methods, the trial did not recruit as planned, and was awarded a no-cost extension to complete the 12-month follow-up.

CONCLUSIONS

The higher number of participants recruited through passive methods may be due to the large number of potential participants these methods reached and because participants may see the information more than once. Recruiting to a child obesity treatment study is complex and it is advisable to use multiple recruitment strategies, some aiming at blanket coverage and some targeted at families with children who are overweight.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN45032201 (Date: 18 August 2011).

Abstract 3737: Use of intestinal organoids as a preclinical screen for agents modulating epithelial regeneration and gastrointestinal toxicity

The mouse small intestinal in vitro organoid model was first described by Sato et al in 2009. We have further developed this model as a robust screening tool to aid the selection of lead candidates that may have efficacy preventing or treating GI toxicity, and to allow early identification of candidate toxicity. More specifically, we have been assessing the model's potential to progress the development of novel therapeutic agents to treat the GI mucositis, a common toxicity associated with cancer therapy.

The intestinal organoid culture conditions were designed to mimic the stem cell niche allowing cell differentiation and proliferation to occur. Indeed all intestinal lineages are present in the organoids and the epithelial hierarchy closely resembles that observed in vivo. Alteration of these organoid culture conditions allows identification of proliferative or cytotoxic effects, changes in differentiation and gene expression profiling of target pathways.

Sub-optimal culture conditions reduce the background level of branching within an organoid population, allowing the quantification of proliferative effects through an increase in branching above the background upon agent exposure. Examples of agents inducing branching of organoids include Wnt pathway modulators. Optimal culture conditions allow assessment of toxicity caused by agents such as chemotherapy drugs. Organoid viability can be assessed either visually or with MTS techniques. In addition, differentiation by agents such as the Notch pathway inhibitor DAPT can be assessed by histological examination of the organoids. All of these cultures can undergo gene expression profiling forming links to the observed biological observations. Proof of concept gene expression data has been generated using known GI growth factors and modulators, which have been linked to in vivo gene expression profiling to demonstrate PD linkages.

In addition, we have developed a model using APCMin+/- mice, which develop a phenotype in culture more consistent with a deregulated adenoma. Parallel assessment of agents on this model and the organoids has been useful for discriminating normal vs tumour responses, identifying agents with differential activities.

Our intestinal organoid models allow screening of multiple agents, with over 5000 screened to date including Wnt pathway regulators, cytokines, growth factor, chemotherapy drugs, steroids and lectins.

Citation Format: Sarah Hoyle, Shaun Ainsworth, Aude-Marine Bonavita, Jo Read, Alan Murdoch, Lorna Woolford, Elliott Harrison, Gino Miele, Cath Booth. Use of intestinal organoids as a preclinical screen for agents modulating epithelial regeneration and gastrointestinal toxicity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3737. doi:10.1158/1538-7445.AM2014-3737

Rapid identification of the genus Dekkera/Brettanomyces, the Dekkera subgroup and all individual species

The genus Dekkera/Brettanomyces comprises five described species: Dekkera bruxellensis, D. anomala, Brettanomyces custersianus, B. naardenensis and B. nanus. Some of them, especially D. bruxellensis, are important spoilage organisms, particularly in the wine and beverage industries. Because of their economic importance many different methods have been developed to identify members of the genus in general and D. bruxellensis in particular. These methods vary in their rapidity, complexity and cost but, partly because of confidentiality issues, it is unclear which methods are used, or how widely, in the relevant industries. Building on previous work with the genera Saccharomyces and Zygosaccharomyces, a suite of eight PCR primer pairs has been designed either on the D1-D2 region of the 26S rRNA gene or translation elongation factor TEF1-α. These primers can specifically identify the genus as a whole, only Dekkera species, each one of the five recognised species as well as a significant subgroup of D. bruxellensis represented by NCYC 3426. Multiplexing has also been tried and it has been shown to be possible with some combinations of genus or Dekkera-level and species-specific primers. Using direct colony PCR amplification followed by gel electrophoresis, a clear positive result can be obtained in less than 3h, thus providing a quick, reliable and inexpensive way to identify target species.

Sex drives intracellular conflict in yeast

Theory predicts that sex can drive the evolution of conflict within the cell. During asexual reproduction, genetic material within the cell is inherited as a single unit, selecting for cooperation both within the genome as well as between the extra-genomic elements within the cell (e.g. plasmids and endosymbionts). Under sexual reproduction, this unity is broken down as parental genomes are distributed between meiotic progeny. Genetic elements able to transmit to more than 50% of meiotic progeny have a transmission advantage over the rest of the genome and are able to spread, even where they reduce the fitness of the individual as a whole. Sexual reproduction is therefore expected to drive the evolution of selfish genetic elements (SGEs). Here, we directly test this hypothesis by studying the evolution of two independent SGEs, the 2-μm plasmid and selfish mitochondria, in populations of Saccharomyces cerevisiae. Following 22 rounds of sexual reproduction, 2-μm copy number increased by approximately 13.2 (±5.6) copies per cell, whereas in asexual populations copy number decreased by approximately 5.1 (±1.5) copies per cell. Given that the burden imposed by this parasite increases with copy number, these results support the idea that sex drives the evolution of increased SGE virulence. Moreover, we found that mitochondria that are respiratory-deficient rapidly invaded sexual but not asexual populations, demonstrating that frequent outcrossed sex can drive the de novo evolution of genetic parasites. Our study highlights the genomic perils of sex and suggests that SGEs may play a key role in driving major evolutionary transitions, such as uniparental inheritance.

All that glitters is not always gold

Biopsies from the second part of the duodenum are routinely performed in patients with unintentional weight loss. When villous atrophy and an increased intraepithelial lymphocytosis are detected, the commonest cause of it is coeliac disease. Severe villous atrophy with increased intraepithelial lymphocytosis (Marsh IIIc) is highly specific for coeliac disease. However, coeliac disease with this presentation is very rare. Milder abnormalities such as Marsh I-II (microscopic enteritis) and Marsh IIIa are not specific for coeliac disease and could occur in other conditions like those listed in the discussion. We present the case of a 74-year-old woman who, after being diagnosed with seronegative coeliac disease, failed to improve on a gluten-free diet. We discuss the differential diagnosis of coeliac disease and the possible alternative causes for villous blunting, paying particular attention to the diagnosis of small intestinal bacterial overgrowth.

Abstract 1867: Gene expression profiles obtained from ex vivo human scalp hair to determine the effects of drug response following exposure to HDAC inhibitors

Background Plucked human scalp hair represents an ideal surrogate tissue to enable non-invasive monitoring of drug response in clinical trials. Congruence of patterns of transcriptome activity within the bulb region of plucked scalp hair show high concordance and to that of primary target tumour tissues. The ex vivo plucked scalp hair culture technique involves exposing healthy normal volunteer hair to different concentrations of a number of HDAC inhibitors and ascertain the effects that they have on gene expression. This technique is an ideal approach to identifying desirable non-invasive transcriptional biomarkers to demonstrate target engagement and define a PK/PD relationship, as well as enabling the monitoring of a well tolerated dose schedule with maximal biological effect. Materials and Methods In this study, we deployed our proprietary ex vivo culture technique to ascertain the effects that three different HDAC inhibitors had on gene expression in plucked hair. Three different concentrations of each HDAC inhibitor were incubated in culture for a period of 18 hours. RNA was extracted from the hair bulb following the culture technique and gene expression was assessed following microarray analysis. Statistically significant biomarkers (p&lt;0.05) were identified along with genes with a greater than 2 fold change from the vehicle group. Direct comparisons in the profiles obtained following exposure to the three different HDAC inhibitors were conducted to evaluate differences in the mechanism of action of each compound. Results We were able to demonstrate from the ex vivo plucked hair study, a panel of transcriptional markers that exhibited a similar response to drug treatment following exposure to the three different HDAC inhibitors. The differentially expressed genes identified were biologically relevant as they are consistent with pathways that are known to be associated with HDAC inhibition. The results also demonstrated the potency of each of the HDAC inhibitors and provided an insight into the different mechanisms of action of each compound. The differentially expressed biomarkers identified in this study may be used in clinical settings to monitor pharmacodynamic responses in plucked scalp hair obtained from patients. Conclusions We conclude that plucked human scalp hair represents an ideal minimally invasive surrogate tissue to monitor drug response in patients receiving treatment with HDAC inhibitors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1867. doi:1538-7445.AM2012-1867

Mannose-binding lectin genotype and serum levels in patients with chronic and allergic pulmonary aspergillosis

Several studies suggest mannose-binding lectin (MBL) deficiency is associated with various manifestations of aspergillosis. MBL serum levels and function are genetically determined, but levels rise during inflammation. We address the relative frequency of deficient genotypes, the relationship between serum level and genotype and both age and disease manifestations in patients with chronic pulmonary (CPA) and allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS). DNA was extracted from blood samples, and MBL2 genotyping was performed using the INNO-LiPA MBL2 kit. Serum MBL concentrations were determined using ELISA. One hundred and eight patients were evaluated, 70 (65%) with CPA, 38 (35%) with allergic disease (ABPA, SAFS or undefined) and 13 (12%) had both CPA and ABPA. The mean MBL serum level was 1849 μg L(-1) and did not differ between groups. Forty subjects (37%) had exon 1 genotypes producing nonfunctional MBL (A/B, A/C, A/D and O/O), a frequency not different from published normal controls. A/A subjects with CPA had higher levels (2981 μg L(-1)) compared with allergic A/A subjects (2202 μg L(-1)) (pc0.012). No single haplotype, genotype or allele was significantly related to any aspergillosis phenotype. Worse breathlessness was associated with higher MBL levels among A/A subjects (P = 0.009) and conversely nonfunctional genotypes. Mean MBL values were higher in those with an Medical Research Council (MRC) breathlessness score of 5 compared with those with and MRC score of 1 (P = 0.023). A/A allergic subjects (n = 27) in this study were ≈ 11 years younger than allergic A/O subjects (n = 11, P = 0.02). Subjects with worse respiratory status or more severe CPA had higher MBL serum levels (P = 0.023; P = 0.034). Bronchiectasis was not associated with MBL levels in CPA or allergic aspergillosis. MBL genotype and serum level modulate progression of aspergillosis.

Abstract C130: Plucked human scalp hairs: Potential utility as a surrogate tissue for the assessment of therapies targeting the androgen receptor

Objective: Evaluate whether plucked human scalp or eyebrow hairs obtained from male elderly healthy normal volunteers (HNVs) are suitable for assessing RNA expression patterns linked to the androgen receptor.

Procedure: For each of 12 HNV subjects plucked eyebrow and scalp hairs were obtained at 2 time points. For each time point up to three individual anagen hairs were selected for RNA extraction and representative cDNA amplification. For each sample RNA quality was assessed by agarose gel electrophoresis and cDNA quality assessed by qPCR analysis of 3 reference or “housekeeping” genes. Expression levels of a panel of 20 androgen receptor regulated genes were measured by qPCR for samples passing both RNA and cDNA quality criteria.

Results : Of the 72 scalp hairs analysed 64 (89 %) passed both RNA and cDNA quality criteria with 23 out of 24 (96%) sample collection points yielding 2 or more analysable hairs. This high success translated into available data for both time points in 11 out of 12 HNVs (92 %). In contrast, for the 72 eyebrow hairs analysed only 2 (3 %) passed RNA quality criteria with none of the collection points yielded 2 or more analysable hairs. Of the 20 test genes qPCR analysis identified a short list of 7 genes with expression levels similar to “housekeeping” genes indicating that they should be reliably detected in the majority of scalp hairs. These results are in keeping with a previous HNV study of younger male and female donors and indicate that plucked scalp hairs may be of value in the early phases of clinical development of androgen receptor based therapies.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C130.

Transcriptional regulation of plant senescence: from functional genomics to systems biology

Leaf senescence is an active process that involves the increased expression of many hundreds of genes. Many putative transcription factors show enhanced transcription during leaf senescence in Arabidopsis and functional analysis of these should help to indicate their role in controlling gene expression during leaf senescence. In this paper, we describe the analysis of knockout insertion mutants in two different senescence-enhanced genes, one encodes a heat shock transcription factor and the other a zinc finger protein. Plants mutated in these genes show accelerated leaf senescence and reduced tolerance to drought stress, indicating that expression of these genes during senescence has a protective role to maintain viability during this essential developmental process. Analysis of gene expression changes in both mutants compared to the wild-type plants indicates an increased rate of senescence but does not show clearly the pathway that is dependent on these genes for expression. The complexities of signalling networks in plant stress and the plasticity of plant responses mean that the direct consequences of mutation are very difficult to define. The usefulness of this type of approach to address the burning question of how senescence is regulated is discussed, and an alternative approach aimed at a more global analysis of gene regulation using systems biology methods is described.

Evaluation of the delivery fee exemption policy in ghana: population estimates of changes in delivery service utilization in two regions

SUMMARY OBJECTIVES

To determine changes in the proportion of deliveries at health facilities and the proportion attended by health professionals after delivery fee exemption implementation.

DESIGN

Pre and post intervention implementation cluster-sampled household survey.

SETTING

Central and Volta regions of Ghana.

PARTICIPANTS

Women who had delivered in these regions during the fee exemption policy and an equivalent period of time prior to it.

MAIN OUTCOME MEASURES

Place of delivery and person attending.

RESULTS

After fee exemption implementation the likelihood of delivering in a health facility increased significantly in Central (OR 1.83, p<0.001) and Volta (OR 1.34, p<0.05) regions when accounting for the mothers' education and poverty levels and the clustered data. Results from Central Region showed increases in facility deliveries mainly occurred in health centres (from 13.7% to 22.3% of deliveries), and were attended by midwives (from 49.0% to 59.7%). There was evidence that after implementation some inequalities in the uptake of facility deliveries decreased. The greatest increase in the proportion of deliveries taking place in facilities occurred among women with the lowest levels of education (Central Region) and wealth (Volta Region). These changes reduced the differentials observed.

CONCLUSIONS

After the implementation of fee exemption the proportion of deliveries in health facilities increased in both regions. Although changes cannot be directly attributed to delivery fee exemption, results demonstrating that the greatest increases in facility-based deliveries occurred among the poorest and least educated women are consistent with the expectation that the policy would particularly benefit women with the greatest financial barrier to health care and at the greatest risk of maternal mortality.

Automated osteoporosis risk assessment by dentists: a new pathway to diagnosis

General dental practitioners use a vast amount of panoramic radiography in their routine clinical work, but valuable information about patients' osteoporotic status is not collected. There are many reasons for this, but one of the prime reasons must be the disruption involved in clinical routine with lengthy manual radiographic assessment. We have developed computer software, based on active shape modeling that will automatically detect the mandibular cortex on panoramic radiographs, and then measure its width. Automatic or semi-automatic measurement of the cortical width will indicate the osteoporotic risk of the patient. The aim of our work was to assess the computer search technique's ability to measure the mandibular cortical width and to assess its potential for detection of osteoporosis of the hip, spine and femoral neck. Mandibular cortical width was measured using the manually initialized (semi-automatic) method and, when assessed for diagnosing osteoporosis at one of the three measurement sites, gave an area under the ROC curve (A(z))=0.816 (95% CI=0.784 to 0.845) and for the automatically initialized searches, A(z)=0.759 (95% CI=0.724 to 0.791). The difference between areas=0.057 (95% Confidence interval=0.025 to 0.089), p<0.0001. For diagnosing osteoporosis at the femoral neck, mandibular cortical width derived from the manually initialized fit gave an area under the ROC curve (A(z))=0.835 (95% CI=0.805 to 0.863) and for the automatically initialized searches A(z)=0.805 (95% CI=0.773 to 0.835). The difference in A(z) values between active shape modeling search methods=0.030 (95% CI=-0.010 to 0.070), and this was not significant, p=0.138. We concluded that measurement of mandibular cortical width using active shape modeling is capable of diagnosing skeletal osteoporosis with good diagnostic ability and repeatability.

Accuracy in osteoporosis diagnosis of a combination of mandibular cortical width measurement on dental panoramic radiographs and a clinical risk index (OSIRIS): the OSTEODENT project

Clinical questionnaires and dental radiographic findings have both been suggested as methods of identifying women at risk of having osteoporosis and who might benefit from bone densitometry. The aim of this study was to measure the diagnostic accuracy of a combination of mandibular cortical width (MCW) measured from dental panoramic radiographs (DPRs) and the osteoporosis index of risk (OSIRIS) in the diagnosis of osteoporosis. 653 women (age range 45-70 years, mean age 54.95 years) in four European centres underwent standardised dual X-ray energy absorptiometry (DXA) to provide reference data on osteoporosis status. Each subject was interviewed to derive OSIRIS scores and underwent DPR examination. MCW was measured directly by five observers. Receiver Operating Characteristic (ROC) curve analysis was used to calculate sensitivities and specificities of the clinical and radiographic tests for the diagnosis of osteoporosis. 512 (78.4%) of the study population were classified as having normal BMD and 141 (21.6%) as having osteoporosis. Using ROC analysis, OSIRIS gave a ROC curve area (A(z)) of 0.838, with a sensitivity of 70.9% and a specificity of 79.5% at a diagnostic threshold of <or=+1. MCW on DPRs gave Az values for the five observers ranging from 0.71 to 0.78, providing sensitivities between 41.0% and 59.6% and specificities of between 81.8% and 90.3% at a diagnostic threshold of a 3 mm MCW and sensitivities between 94.2% and 99.3% and specificities of between 9.8% and 23.7% at a diagnostic threshold of a 4.5 mm MCW. Inter-observer repeatability was less than 2.15 mm for 95% of subjects. Combining clinical and radiographic tests had the effect of improving specificity at the expense of a fall in sensitivity. Diagnostic thresholds for MCW and OSIRIS can be chosen to provide the sensitivity and specificity combination that best suits locally determined needs. However, the addition of OSIRIS as a stepwise 'follow-up' test to radiographic assessment of MCW should only be performed if the aim is to have a test for which the highest achievable specificity is desired.

Comparative gene expression in brain regions of human alcoholics

The mesocorticolimbic system is the reward centre of the brain and the major target for drugs of abuse including alcohol. Neuroadaptive changes in this region are thought to underlie the process of tolerance and dependence. Recently, several research groups have searched for alcohol-responsive genes using high-throughput microarrays and well-characterized human post-mortem material. Comparison of data from these studies of cortical regions highlights the differences in experimental approach and selection of cases. However, alcohol-responsive gene sets associated with transcription, oxidative stress and energy production were common to these studies. In marked contrast, alcohol-responsive genes in the nucleus accumbens and the ventral tegmental area are primarily associated with changes in neurotransmission and signal transduction. These data support the concept that, within cortical regions, changes in gene expression are associated with alcoholism-related pathology. In the dopaminergic tract of the mesocorticolimbic system, alcohol-responsive gene sets suggest long-term neuroplastic changes in synaptic transmission.

Comparison of resection and radiofrequency ablation for treatment of solitary colorectal liver metastases

BACKGROUND

Liver resection is the treatment of choice for patients with solitary colorectal liver metastases. In recent years, however, radiofrequency ablation has been used increasingly in the treatment of colorectal liver metastases. In the absence of randomized clinical trials, this study aimed to compare outcome in patients with solitary colorectal liver metastases treated by surgery or by radiofrequency ablation.

METHODS

Solitary colorectal liver metastases were treated by radiofrequency destruction in 25 patients. The indications were extrahepatic disease in seven, vessel contiguity in nine and co-morbidity in nine patients. Outcome was compared with that of 20 patients who were treated by liver resection for solitary metastases and had no evidence of extrahepatic disease. Most patients in both groups also received systemic chemotherapy.

RESULTS

Median survival after liver resection was 41 (range 0-97) months with a 3-year survival rate of 55.4 per cent. There was one postoperative death and morbidity was minimal. Median survival after radiofrequency ablation was 37 (range 9-67) months with a 3-year survival rate of 52.6 per cent.

CONCLUSION

Survival after resection and radiofrequency ablation of solitary colorectal liver metastases was comparable. The latter is less invasive and requires either an overnight stay or day-case facilities only.