229 EXPRESSION OF mRNA ENCODING GLYCOLYTIC ENZYMES IN BOVINE CUMULUS CELLS DURING IN VITRO MATURATION: EFFECTS OF TIME AND FSH

Mammalian oocytes require pyruvate as an energy source for growth and resumption of meiosis. Because oocytes are not competent to carry out glycolysis, cumulus cells (CC) are responsible for metabolizing glucose into pyruvate and providing it to the oocyte through gap junctions. The understanding of the energetic metabolism of CC in culture conditions might provide basis for the improvement of COC in vitro maturation. The aim of this study was to determine the temporal patterns of mRNA expression of glycolytic enzymes [phosphofructokinase (PFKP), aldolase (ALDOA), triosephosphate isomerase (TPI), enolase (ENO1), pyruvate kinase (PKM2), and lactate dehydrogenase (LDHA)] in bovine CC during COC in vitro maturation with or without FSH. Immature COC (grades 1 and 2) were obtained from 2- to 8-mm follicles from abattoir ovaries (predominantly Bos indicus). Cumulus cells were separated from COC and frozen before (immature group) or after COC culture for 4, 8, 12, 16, and 20 hours with (10 ng/mL) or without FSH. Total RNA was extracted using RNeasy® (Qiagen, Valencia, CA, USA), and 100 ng of RNA was reverse transcribed using oligo dT primers and Omniscript® (Qiagen). Relative expression of target genes was assessed by real-time PCR using bovine-specific primers and Power SYBR green master mix in an ABI Prism® 7300. To select the most stable housekeeping gene for expression normalization, cyclophilin-A (CYC-A), GAPDH, and histone H2AFZ amplification profiles were compared using the geNorm applet for Microsoft Excel (Vandesompele J et al. 2002 Genome Biol. 3, 1-11); the most stable housekeeping gene was CYC-A. Relative expression values were calculated using the AACt method with efficiency correction (Pfaffl MW 2001 Nucleic Acids Res. 29, 2002-2007). Effects of time in culture and of FSH treatment were tested by ANOVA, and groups were compared by Tukey-Kramer Honestly Significant Difference test. Nonparametric analysis was used when data were not normally distributed. Abundance of mRNA of all glycolytic enzymes decreased during in vitro maturation with or without FSH. Expression of PFKP, ALDOA, TPI1, ENO1, and LDHA genes was decreased to around half of the initial value (time 0) by 4 to 8 h of culture (P < 0.05) and did not increase thereafter. A similar expression pattern was observed for PKM2, although mRNA abundance was reduced later in comparison with other enzymes; levels were decreased by 16 (without FSH) to 20 h (with FSH) of culture. The presence of FSH did not alter the overall temporal pattern of gene expression but decreased mRNA abundance for PFKP, ALDOA, and TPI1 at 20, 16 and 16 h of culture, respectively. In conclusion, gene expression of glycolytic enzymes decreased with time during COC in vitro maturation in cattle, and FSH did not have a major influence on this expression pattern. This study was supported by CAPES and FAPESP.

210 EXPRESSION OF mRNA ENCODING STEROIDOGENIC ENZYMES IN THE DEVELOPING BOVINE OVARY

Recent findings suggest a role for estradiol in the regulation of early folliculogenesis. Estradiol production is greatest in the fetal ovary during early gestation in cattle, and both estradiol and progesterone inhibit primordial follicle activation (Yang MY and Fortune JE 2008 Biol. Reprod. 78 (Suppl 6), 1153-1161). Aromatase expression is detected in early stages of bovine pregnancy (Garverick HA et al. 2009 Anim. Reprod. Sci. in press). The mechanisms controlling steroidogenesis in the bovine fetal ovary remain to be fully elucidated. The objective of this study was to assess mRNA expression patterns of enzymes involved in steroid production [steroidogenic acute regulatory protein (STAR), side-chain cleavage P450 (CYP11), cytochrome P450 17 alpha-hydroxylase (CYP17A1), 3 beta-hydroxysteroid dehydrogenase (3fi-HSD), aromatase cytochrome P450 (CYP19), and 17 beta-hydroxysteroid dehydrogenase (17fi-HSD)] in bovine fetal ovaries during gestation. Bovine fetal ovaries were obtained in a local slaughterhouse, fetal age was estimated by the crown-rump length, and samples were grouped according with days of gestation as follows: 60 (n = 5), 75 (n = 8), 90 (n = 6), 120 (n = 7), 150 (n = 7), and 210 (n = 6). Expression of mRNA encoding steroidogenic enzymes was determined by semiquantitative real-time RT-PCR using bovine-specific primers and cyclophilin A as endogenous control. Reverse transcription was performed with SuperScriptIII® (Invitrogen, Carlsbad, CA, USA) and PCR with Power SYBR green master mix (Applied Biosystems, Foster City, CA, USA) in an ABI Prism® 7500 (Applied Biosystems). Gene expression values were determined by the Pfaffl equation and effect of day of gestation on gene expression was analyzed with Fisher’s protected test, except when data were not normally distributed and nonparametric analysis was performed. Expression of mRNA encoding all steroidogenic enzymes was detected throughout gestation. The mRNA abundance of CYP17A1 and CYP19 was highest at 60 days of gestation and decreased thereafter (P < 0.05). Expression of all other genes did not significantly vary with time of gestation. In conclusion, all major enzymes required for steroidogenesis were expressed in the bovine fetal ovary. Expression of CYP17A1 and CYP19 was suppressed after 60 days of gestation, suggesting that these enzymes may be involved in the mechanisms controlling estradiol production and follicle formation in the bovine fetal ovary. Supported by CAPES and FAPESP.

Time Dependent Improvement in Survival for Women with Multiple Brain Metastases from HER2 Positive Breast Cancer: The Influence of Systemic Therapy

Background: Women with multiple breast cancer brain metastases (BM) ineligible for neurosurgery or radiosurgery have a poor prognosis and the role of systemic therapy is ill defined.Method: The outcomes for 120 women treated for multiple (≥2) BM between 2002-2008 at this regional cancer centre have been analysed according to time of BM diagnosis (Cohorts (A) 2002-5 & (B) 2006-8) and HER2 status of the primary tumour (+ or -). We have previously shown that A+ patients experienced longer survival than A-, the advantage apparently restricted to a subgroup of A+ who continued trastuzumab after BM diagnosis (Church et al, Am J Clin Oncol 2008, 31(3) 250-4).Results: There was no difference in survival between B- and A- cohorts (B- patients (n=25) survival median 119 days; A- patients (n=53) median survival 118 days; p=0.57). In contrast there was a time dependent improvement in survival favouring B+ patients (n=19, median 520 days,) over A+ patients (n=23, median 148 days, p &lt;0.02). B+ and A+ cohorts differed significantly in the consistency of their exposure to both trastuzumab (T) and chemotherapy (CT) post BM (p&lt;0.02). Subsequently, patients in the B+ cohort was more frequently treated with additional lines of CT and 5 patients in the B+ cohort (versus none in A+) went on to receive second line anti-HER2 therapy (lapatinib).CohortT + CTLines of CT≥ 2LapatinibMedian survival12 month survivalA+ (n=23)39% (9pts)22% (5)0% (o)148 days30%B+ (n=19)79% (15pts)58% (11)26% (5)520 days80% p&lt;0.02p&lt;0.03p&lt;0.02p&lt;0.02 A+ and B+ were not significantly different with regard to presence of systemic metastases (SM) or time from SM to BM (median A+ 304 days; B+ 334, p=0.3)Conclusion: Following our earlier observation on the A+ cohort, the improvement in survival for B+ may reflect increased optimism of patients and physicians regarding the role of systemic therapy. Although no randomised trial has been performed, it is increasingly apparent from these and other data that HER2+ patients with multiple BM benefit from continued incorporation of systemic therapy into clinical management strategies and, at variance with historic experience, survival &gt; 1 year can now be expected. Randomised trials, specifically to identify the best agents to accompany anti-HER2 therapy, will be required to further extend this benefit.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5092.

Validation of the quality of The National Pain Database for pain management services in the United Kingdom

Data on specialist pain management is scarce. We evaluated PainDB, a database which aggregates this information from UK pain clinics. PainDB entries for 1120 patients (2648 consultations) were compared to records at 30 pain clinics. Staff were surveyed about normal practice at 28 sites. First consultations (17 135) on the aggregated PainDB were analysed for 2003 for omissions. Those consultations included on PainDB (54.6%) showed good concurrence with written notes (88.1%), with no pattern for the missing visits. Questionnaire responses were often absent from notes (56%) and diagnosis was most frequently omitted from PainDB (12.4-18.4%). Clinic staff overestimated completeness. Despite commitment, PainDB is currently unsuitable for research or audit. As routine hospital data should provide information on activity, specific questions on severity and outcome could be answered by short-term recording of predefined variables.

Parotid gland enlargement in eating disorders: an insensitive sign?

OBJECTIVE

To study, using magnetic resonance imaging (MRI), the parotid glands of patients who self-induce vomiting and in particular to observe the effects of cessation of this behaviour. The morphological features and composition of enlarged parotid glands in this group, compared with normal controls, were also examined.

METHOD

MRI scans of the parotid glands were performed on 5 controls and 5 subjects with a purging form of eating disorder, at cessation of vomiting and 6 to 9 weeks later.

RESULTS

Parotid volumes are accurately measured using MRI. Enlarged parotids are not a consistent feature of subjects with eating disorders who self-induce vomiting.

CONCLUSION

Absence of salivary gland enlargement does not exclude significant vomiting behaviour and clinicians should remain alert to the possibility of undisclosed vomiting.

An effective system of nurse-led diabetes care in rural Africa

AIMS

Delivering adequate diabetes care is difficult in rural Africa because of drug and equipment shortages; as well as lack of trained medical expertise. We aimed to set up and evaluate a nurse-led protocol and education-based system in rural Kwazulu Natal in South Africa.

METHODS

A treatment algorithm and education system adapted from previously validated methods was used; care was devolved to primary health clinics and was delivered by two nurses. Glycaemic control was assessed by glycated haemoglobin (HbA1c), assayed off site and not available for clinical use during the study. Results A total of 284 patients were enrolled, with 197 followed for 18 months (13 died and 26% lapsed during the period). HbA1c was 11.6 +/- 4.5% (sd) at baseline, 8.7 +/- 2.3% at 6 months and 7.7 +/- 2.0% at 18 months. There was a small associated increase in weight but no increase in hypoglycaemia. Subgroup analysis showed that education alone, without drug type or dose changes, also improved control (HbA1c 10.6 +/- 4.2% baseline and 7.6 +/- 2.3% at 18 months). The service was very popular with patients, families and other health workers.

CONCLUSIONS

We conclude that a simple protocol and education-based diabetes care system can be successfully introduced and run by nurses in rural Africa. Medium-term glycaemic improvements are excellent and the service has been very well received.

Estimating the magnitude of trastuzumab effects within patient subgroups in the HERA trial

BACKGROUND

Trastuzumab (Herceptin(R)) improves disease-free survival (DFS) and overall survival for patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer. We aimed to assess the magnitude of its clinical benefit for subpopulations defined by nodal and steroid hormone receptor status using data from the Herceptin Adjuvant (HERA) study.

PATIENTS AND METHODS

HERA is an international multicenter randomized trial comparing 1 or 2 years of trastuzumab treatment with observation after standard chemotherapy in women with HER2-positive breast cancer. In total, 1703 women randomized to 1-year trastuzumab and 1698 women randomized to observation were included in these analyses. Median follow-up was 23.5 months. The primary endpoint was DFS.

RESULTS

The overall hazard ratio (HR) for trastuzumab versus observation was 0.64 [95% confidence interval (CI) 0.54-0.76; P < 0.0001], ranging from 0.46 to 0.82 for subgroups. Estimated improvement in 3-year DFS in subgroups ranged from +11.3% to +0.6%. Patients with the best prognosis (those with node-negative disease and tumors 1.1-2.0 cm) had benefit similar to the overall cohort (HR 0.53, 95% CI 0.26-1.07; 3-year DFS improvement +4.6%, 95% CI -4.0% to 13.2%).

CONCLUSIONS

Adjuvant trastuzumab therapy reduces the risk of relapse similarly across subgroups defined by nodal status and steroid hormone receptor status, even those at relatively low risk for relapse.

Provisional guidelines for applying the Department of Health (England) 18-week-patient pathway to specialist rheumatology care

OBJECTIVES

The Government Department of Health (England) has set a target that by 2008 patients on pathways that do or may involve medical or surgical consultant-led care should wait no longer than 18 weeks from referral to start of definitive treatment. Department of Health guidance must be interpreted and applied to patients with rheumatological problems.

METHODS

Provisional guidelines have been prepared in collaboration between the British Society for Rheumatology, British Pain Society, Department of Health (England) and other key stakeholders.

RESULTS

Definitive rheumatological treatment comprises a package of care rather than a single action. The care package usually requires input from a multidisciplinary team using several modalities in parallel. Actions within the care package that must be taken before treatment can be said to have started, are definitive actions. Definitive actions should be based on evidence of cost-effectiveness, tailored to the individual patient and offered irrespective of local availability or accessibility. They should be agreed between partners in the patient's care. This requires face-to-face consultation between the patient and a health care professional with appropriate expertise and knowledge. All definitive actions specified at the outset of management within specialist care must be initiated or removed by agreement from the patient's care package before the clock can be stopped in the 18-week-patient pathway.

CONCLUSIONS

Service redesign may be necessary in order to achieve an 18-week-patient pathway for all patients. A consistent and appropriate definition of clock-stops should ensure that patients will benefit from excellent rheumatology specialist care without unnecessary delay.

EMG biofeedback for the recovery of motor function after stroke

BACKGROUND

Electromyographic biofeedback (EMG-BFB) is a technique that is believed to have additional benefit when used with standard physiotherapy for the recovery of motor function in stroke patients. However, evidence from individual trials and previous systematic reviews has been inconclusive.

OBJECTIVES

To assess the effects of EMG-BFB for motor function recovery following stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched 30 March 2006), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2005), MEDLINE (1966 to November 2005), EMBASE (1980 to November 2005), CINAHL (1983 to November 2005), PsycINFO (1974 to November 2005) and First Search (1966 to November 2005). We scanned reference lists for relevant articles and contacted equipment manufacturers and distributors.

SELECTION CRITERIA

Randomised and quasi-randomised studies comparing EMG-BFB with control for motor function recovery in stroke patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Where possible we contacted study authors for further information. Any reported adverse effects were noted.

MAIN RESULTS

Thirteen trials involving 269 people were included. All trials compared EMG-BFB plus standard physiotherapy to standard physiotherapy either alone or with sham EMG-BFB. Only one study used a motor strength assessment scale for evaluation of patients, which indicated benefit from EMG-BFB (WMD 1.09, 95% CI 0.48 to 1.70). EMG-BFB did not have a significant benefit in improving range of motion (ROM) through the ankle (SMD 0.05, 95% CI -0.36 to 0.46), knee or wrist joints. However, one trial suggested a benefit in ROM at the shoulder (SMD 0.88, 95% CI 0.07 to 1.70). Change in stride length or gait speed was not improved by EMG-BFB. Two studies used different assessment scores to quantify gait quality. One of these suggested a beneficial effect of EMG-BFB (SMD 0.90, 95% CI 0.01 to 1.78). Most of the studies examining functional outcomes used different assessment scales, which made meta-analysis impossible. Two studies that used the same scale did show a beneficial effect (SMD 0.69, 95% CI 0.15 to 1.23).

AUTHORS' CONCLUSIONS

Despite evidence from a small number of individual studies to suggest that EMG-BFB plus standard physiotherapy produces improvements in motor power, functional recovery and gait quality when compared to standard physiotherapy alone, combination of all the identified studies did not find a treatment benefit. Overall the results are limited because the trials were small, generally poorly designed and utilised varying outcome measures.

Transfusion-related acute lung injury in the paediatric patient: Two case reports and a review of the literature

Transfusion-related acute lung injury (TRALI) is increasingly recognized as a major complication of transfusion therapy; it was the leading cause of transfusion-related fatalities in the United States in 2003. Most cases of TRALI that have been reported are in adult patients. We present two cases of TRALI that occurred in children and review the existing literature of paediatric TRALI. The paediatric TRALI case reports highlight two laboratory findings that can help in the diagnosis of TRALI: transient leucopenia and an elevated pulmonary oedema fluid/plasma protein ratio. These two simple diagnostic tests can help rule out other diagnoses and add confidence to the clinical diagnosis of TRALI. Finally, our first case also highlights the potential danger of directed maternal blood donations, which may increase the risk of paediatric TRALI.

Strength of cancellous bone trabecular tissue from normal, ovariectomized and drug-treated rats over the course of ageing

Hormone therapy (HT) drugs and bisphosphonates prevent osteoporosis by inhibiting osteoclastic bone resorption. However, the effects of osteoporosis and anti-resorptive drugs on the mechanical behavior of the bone tissue constituting individual trabeculae have not yet been quantified. In this study, we test the hypothesis that the mechanical properties of bone trabecular tissue will differ for normal, ovariectomized and drug-treated rat bones over the course of ageing. Microtensile testing is carried on individual trabeculae from tibial bone of ovariectomized (OVX) rats, OVX rats treated with tibolone and placebo-treated controls. The method developed minimizes errors due to misalignment and stress concentrations at the grips. The local mineralization of single trabeculae is compared using micro-CT images calibrated for bone mineral content assessment. Our results indicate that ovariectomy in rats increases the stiffness, yield strength, yield strain and ultimate stress of the mineralized tissue constituting trabecular bone relative to normal; we found significant differences (P < 0.05) at 14, 34 and 54 weeks of treatment. These increases are complemented by a significant increase in the mineral content at the tissue level, although overall bone mineral density and mass are reduced. With drug treatment, the properties remain at, or slightly below, the placebo-treated controls levels for 54 weeks. The higher bone strength in the OVX group may cause the trabecular architecture to adapt as seen during osteopenia/osteoporosis, or alternately it may compensate for loss of trabecular architecture. These findings suggest that, in addition to the effects of osteoporosis and subsequent treatment on bone architecture, there are also more subtle processes ongoing to alter bone strength at the tissue level.

Cost-effectiveness and safety of epidural steroids in the management of sciatica

OBJECTIVES

To investigate the clinical effectiveness of epidural steroid injections (ESIs) in the treatment of sciatica with an adequately powered study and to identify potential predictors of response to ESIs. Also, to investigate the safety and cost-effectiveness of lumbar ESIs in patients with sciatica.

DESIGN

A pragmatic, prospective, multicentre, double-blind, randomised, placebo-controlled trial with 12-month follow-up was performed. Patients were stratified according to acute (<4 months since onset) versus chronic (4-18 months) presentation. All analyses were performed on an intention-to-treat basis with last observation carried forward used to impute missing data.

SETTING

Rheumatology, orthopaedic and pain clinics in four participating centres: three district hospitals and one teaching hospital in the south of England.

PARTICIPANTS

Total of 228 patients listed for ESI with clinically diagnosed unilateral sciatica, aged between 18 and 70 years, who had a duration of symptoms between 4 weeks and 18 months.

INTERVENTIONS

Patients received up to three injections of epidural steroid and local anaesthetic (active), or an injection of normal saline into the interspinous ligament (placebo).

MAIN OUTCOME MEASURES

The primary outcome measure was the Oswestry Disability Questionnaire (ODQ); measures of pain relief and psychological and physical function were collected. Health economic data on return to work, analgesia use and other interventions were also measured. Quality-adjusted life-years (QALYs) were calculated using the SF-6D, calculated from the Short Form (SF-36). Costs per patient were derived from figures supplied by the centres' finance departments and a costings exercise performed as part of the study. A cost-utility analysis was performed using the SF-36 to calculate costs per QALY.

RESULTS

ESI led to a transient benefit in ODQ and pain relief, compared with placebo at 3 weeks (p = 0.017, number needed to treat = 11.4). There was no benefit over placebo between weeks 6 and 52. Using incremental QALYs, this equates to and additional 2.2 days of full health. Acute sciatica seemed to respond no differently to chronic sciatica. There were no significant differences in any other indices, including objective tests of function, return to work or need for surgery at any time-points. There were no clinical predictors of response, although the trial lacked sufficient power to be confident of this. Adverse events were uncommon, with no difference between groups. Costs per QALY to providers under the trial protocol were 44,701 pounds sterling. Costs to the purchaser per QALY were 354,171 pounds sterling. If only one ESI was provided then costs per QALY fell to 25,745 pounds sterling to the provider and 167,145 pounds sterling to the purchaser. ESIs thus failed the QALY threshold recommended by the National Institute for Health and Clinical Excellence (NICE).

CONCLUSIONS

Although ESIs appear relatively safe, it was found that they confer only transient benefit in symptoms and self-reported function in a small group of patients with sciatica at substantial costs. ESIs do not provide good value for money if NICE recommendations are followed. Additional research is suggested into the epidemiology of radicular pain, producing a register of all ESIs, possible subgroups who may benefit from ESIs, the use of radiological imaging, optimal early interventions, analgesic agents and nerve root injections, the use of cognitive behavioural therapy in rehabilitation, improved methods of assessment, a comparative cost-utility analysis between various treatment strategies, and methods to reduce the effect of scarring and inflammation.

A multicentre randomized controlled trial of epidural corticosteroid injections for sciatica: the WEST study

OBJECTIVE

To determine the effectiveness and predictors of response to lumbar epidural corticosteroid injections (ESI) in patients with sciatica. We performed a 12-month, multicentre, double-blind, randomized, placebo-controlled, parallel-group trial in four secondary pain-care clinics in the Wessex Region.

METHODS

Two hundred and twenty-eight patients with a clinical diagnosis of unilateral sciatica of 1-18 months' duration were randomized to either three lumbar ESIs of triamcinolone acetonide or interligamentous saline injections at intervals of 3 weeks. The main outcome measure was the Oswestry low back pain disability questionnaire (ODQ).

RESULTS

At 3 weeks, the ESI group demonstrated a transient benefit over the placebo group (patients achieving a 75% improvement in ODQ, 12.5 vs 3.7%; number needed to treat, 11.4). No benefit was demonstrated from 6 to 52 weeks. ESIs did not improve physical function, hasten return to work or reduce the need for surgery. There was no benefit of repeated ESIs over single injection. No clinical predictors of response were found. At the end of the study the majority of patients still had significant pain and disability regardless of intervention.

CONCLUSIONS

In this pragmatic study, ESIs offered transient benefit in symptoms at 3 weeks in patients with sciatica, but no sustained benefits in terms of pain, function or need for surgery. Sciatica is a chronic condition requiring a multidisciplinary approach. To fully investigate the value of ESIs, they need to be evaluated as part of a multidisciplinary approach.

Brain abnormalities underlying altered activation in dyslexia: a voxel based morphometry study

Voxel-based morphometry was used to assess the consistency among functional imaging and brain morphometry data in developmental dyslexia. Subjects, from three different cultural contexts (UK, France and Italy), were the same as those described in a previous PET activation paper, which revealed a common pattern of reduced activation during reading tasks in the left temporal and occipital lobes. We provide evidence that altered activation observed within the reading system is associated with altered density of grey and white matter of specific brain regions, such as the left middle and inferior temporal gyri and the left arcuate fasciculus. This supports the view that dyslexia is associated with both local grey matter dysfunction and with altered connectivity among phonological/reading areas. The differences were replicable across samples confirming that the neurological disorder underlying dyslexia is the same across the cultures investigated in the study.

The genome of the social amoeba Dictyostelium discoideum

The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. Here we describe the genome of the best-studied member of this group, Dictyostelium discoideum. The gene-dense chromosomes of this organism encode approximately 12,500 predicted proteins, a high proportion of which have long, repetitive amino acid tracts. There are many genes for polyketide synthases and ABC transporters, suggesting an extensive secondary metabolism for producing and exporting small molecules. The genome is rich in complex repeats, one class of which is clustered and may serve as centromeres. Partial copies of the extrachromosomal ribosomal DNA (rDNA) element are found at the ends of each chromosome, suggesting a novel telomere structure and the use of a common mechanism to maintain both the rDNA and chromosomal termini. A proteome-based phylogeny shows that the amoebozoa diverged from the animal-fungal lineage after the plant-animal split, but Dictyostelium seems to have retained more of the diversity of the ancestral genome than have plants, animals or fungi.

Introduction to the DAPPLE Air Pollution Project

The Dispersion of Air Pollution and its Penetration into the Local Environment (DAPPLE) project brings together a multidisciplinary research group that is undertaking field measurements, wind tunnel modelling and computer simulations in order to provide better understanding of the physical processes affecting street and neighbourhood-scale flow of air, traffic and people, and their corresponding interactions with the dispersion of pollutants at street canyon intersections. The street canyon intersection is of interest as it provides the basic case study to demonstrate most of the factors that will apply in a wide range of urban situations. The aims of this paper are to introduce the background of the DAPPLE project, the study design and methodology for data collection, some preliminary results from the first field campaign in central London (28 April-24 May 2003) and the future for this work. Updated information and contact details are available on the web site at http://www.dapple.org.uk.

The neural areas that control the retrieval and selection of semantics

Semantic retrieval consistently activates left inferior frontal regions, yet lesions to these areas do not typically result in semantic deficits. This discrepancy has led to the hypothesis that left prefrontal areas are primarily involved in executive processes while semantic information is retrieved from temporal cortices. We investigated semantic executive processing by changing, over trials, the semantic association to a stimulus. Using fMRI and PET, we demonstrate that changes in semantic association increased activation in temporal as well as frontal areas. The similar effects in temporal and frontal areas suggest that semantic executive processes are not confined to the left inferior frontal cortex but might be distributed throughout the semantic system.

Genome sequence of the enterobacterial phytopathogen Erwinia carotovora subsp. atroseptica and characterization of virulence factors

The bacterial family Enterobacteriaceae is notable for its well studied human pathogens, including Salmonella, Yersinia, Shigella, and Escherichia spp. However, it also contains several plant pathogens. We report the genome sequence of a plant pathogenic enterobacterium, Erwinia carotovora subsp. atroseptica (Eca) strain SCRI1043, the causative agent of soft rot and blackleg potato diseases. Approximately 33% of Eca genes are not shared with sequenced enterobacterial human pathogens, including some predicted to facilitate unexpected metabolic traits, such as nitrogen fixation and opine catabolism. This proportion of genes also contains an overrepresentation of pathogenicity determinants, including possible horizontally acquired gene clusters for putative type IV secretion and polyketide phytotoxin synthesis. To investigate whether these gene clusters play a role in the disease process, an arrayed set of insertional mutants was generated, and mutations were identified. Plant bioassays showed that these mutants were significantly reduced in virulence, demonstrating both the presence of novel pathogenicity determinants in Eca, and the impact of functional genomics in expanding our understanding of phytopathogenicity in the Enterobacteriaceae.