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The catechol-o-methyltransferase (COMT) gene has been extensively investigated in depression with somewhat contradictory results but the role of impulsivity, as a possible intermediate phenotype in this disorder, has not been considered yet. In our study, four tagging SNPs in the COMT gene (rs933271, rs740603, rs4680, rs4646316) were genotyped in two independent population cohorts: Manchester (n = 1267) and Budapest (n = 942). First, we investigated the association between COMT genotypes, impulsivity, neuroticism and depression using haplotype trend regression, and constructed a model using structural equation modeling to investigate the interaction between these factors. Secondly, we tested the effect of executive function on this model in a smaller interviewed sample (n = 207). Our results demonstrated that COMT haplotypes were significantly associated with impulsivity in the combined cohort, showing the same direction of effects in both populations. The COMT effect on depressive symptoms (in subjects without history of depression) and on executive function (interviewed sample) showed the opposite pattern to impulsivity. Structural equation models demonstrated that COMT and impulsivity acted, both together (through neuroticism) and independently, to increase the risk of depression. In addition, better executive function also operated as a risk factor for depression, possibly though reduced ability to flexibly disengage negative emotions. In conclusion, variations in the COMT gene exert complex effects on susceptibility to depression involving various intermediate phenotypes, such as impulsivity and executive function. These findings emphasise that modeling of disease pathways at phenotypic level are valuable for identifying genetic risk factors., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Urinary tract infection (UTI) is common in children, and may cause serious illness and recurrent symptoms. However, obtaining a urine sample from young children in primary care is challenging and not feasible for large numbers. Evidence regarding the predictive value of symptoms, signs and urinalysis for UTI in young children is urgently needed to help primary care clinicians better identify children who should be investigated for UTI. This paper describes the protocol for the Diagnosis of Urinary Tract infection in Young children (DUTY) study. The overall study aim is to derive and validate a cost-effective clinical algorithm for the diagnosis of UTI in children presenting to primary care acutely unwell., Methods/design: DUTY is a multicentre, diagnostic and prospective observational study aiming to recruit at least 7,000 children aged before their fifth birthday, being assessed in primary care for any acute, non-traumatic, illness of ≤ 28 days duration. Urine samples will be obtained from eligible consented children, and data collected on medical history and presenting symptoms and signs. Urine samples will be dipstick tested in general practice and sent for microbiological analysis. All children with culture positive urines and a random sample of children with urine culture results in other, non-positive categories will be followed up to record symptom duration and healthcare resource use. A diagnostic algorithm will be constructed and validated and an economic evaluation conducted.The primary outcome will be a validated diagnostic algorithm using a reference standard of a pure/predominant growth of at least >103, but usually >105 CFU/mL of one, but no more than two uropathogens.We will use logistic regression to identify the clinical predictors (i.e. demographic, medical history, presenting signs and symptoms and urine dipstick analysis results) most strongly associated with a positive urine culture result. We will then use economic evaluation to compare the cost effectiveness of the candidate prediction rules., Discussion: This study will provide novel, clinically important information on the diagnostic features of childhood UTI and the cost effectiveness of a validated prediction rule, to help primary care clinicians improve the efficiency of their diagnostic strategy for UTI in young children.

Objective: To evaluate the effectiveness on glycaemic control of a training programme in consultation skills for paediatric diabetes teams., Design: Pragmatic cluster randomised controlled trial., Setting: 26 UK secondary and tertiary care paediatric diabetes services., Participants: 79 healthcare practitioners (13 teams) trained in the intervention (359 young people with type 1 diabetes aged 4-15 years and their main carers) and 13 teams allocated to the control group (334 children and their main carers)., Intervention: Talking Diabetes programme, which promotes shared agenda setting and guiding communication style, through flexible menu of consultation strategies to support patient led behaviour change., Main Outcome Measures: The primary outcome was glycated haemoglobin (HbA(1c)) level one year after training. Secondary outcomes were clinical measures (hypoglycaemic episodes, body mass index, insulin regimen), general and diabetes specific quality of life, self reported and proxy reported self care and enablement, perceptions of the diabetes team, self reported and carer reported importance of, and confidence in, undertaking diabetes self management measured over one year. Analysis was by intention to treat. An integrated process evaluation included audio recording a sample of 86 routine consultations to assess skills shortly after training (intervention group) and at one year follow-up (intervention and control group). Two key domains of skill assessment were use of the guiding communication style and shared agenda setting., Results: 660/693 patients (95.2%) provided blood samples at follow-up. Training diabetes care teams had no effect on HbA(1c) levels (intervention effect 0.01, 95% confidence interval -0.02 to 0.04, P=0.5), even after adjusting for age and sex of the participants. At follow-up, trained staff (n=29) were more capable than controls (n=29) in guiding (difference in means 1.14, P<0.001) and agenda setting (difference in proportions 0.45, 95% confidence interval 0.22 to 0.62). Although skills waned over time for the trained practitioners, the reduction was not significant for either guiding (difference in means -0.33, P=0.128) or use of agenda setting (difference in proportions -0.20, -0.42 to 0.05). 390 patients (56%) and 441 carers (64%) completed follow-up questionnaires. Some aspects of diabetes specific quality of life improved in controls: reduced problems with treatment barriers (mean difference -4.6, 95% confidence interval -8.5 to -0.6, P=0.03) and with treatment adherence (-3.1, -6.3 to -0.01, P=0.05). Short term ability to cope with diabetes increased in patients in intervention clinics (10.4, 0.5 to 20.4, P=0.04). Carers in the intervention arm reported greater excitement about clinic visits (1.9, 1.05 to 3.43, P=0.03) and improved continuity of care (0.2, 0.1 to 0.3, P=0.01)., Conclusions: Improving glycaemic control in children attending specialist diabetes clinics may not be possible through brief, team-wide training in consultation skills., Trial Registration: Current Controlled Trials ISRCTN61568050.

Using a human Prostaglandin E(2) (PGE(2)) model of headache, we examined whether a novel potent and selective EP(4) receptor antagonist, BGC20-1531, may prevent headache and dilatation of the middle cerebral (MCA) and superficial temporal artery (STA). In a three-way cross-over trial, eight healthy volunteers were randomly allocated to receive 200 and 400 mg BGC20-1531 and placebo, followed by a 25-min infusion of PGE(2). We recorded headache intensity on a verbal rating scale, MCA blood flow velocity and STA diameter. There was no difference in headache response or prevention of the dilation of the MCA or the STA (P > 0.05) with either dose of BGC20-1531 relative to placebo, although putative therapeutic exposures were not reached in all volunteers. In conclusion, these data suggest that the other EP receptors may be involved in PGE(2) induced headache and dilatation in normal subjects.

Mutual information (I) provides a robust measure of genetic differentiation for the purposes of estimating dispersal between populations. At present, however, there is little predictive theory for I. The growing importance in population biology of analyses of single-nucleotide and other single-feature polymorphisms (SFPs) is a potent reason for developing an analytic theory for I with respect to a single locus. This study represents a first step towards such a theory. We present theoretical predictions of I between two populations with respect to a single haploid biallelic locus. Dynamical and steady-state forecasts of I are derived from a Wright-Fisher model with symmetrical mutation between alleles and symmetrical dispersal between populations. Analytical predictions of a simple Taylor approximation to I are in good agreement with numerical simulations of I and with data on I from SFP analyses of dispersal experiments on Drosophila fly populations. The theory presented here also provides a basis for the future inclusion of selection effects and extension to multiallelic loci., (© 2011 Blackwell Publishing Ltd.)

Tandem insertion of 1,1-dihalo-1-lithio species (halocarbenoids) and lithium alkynides into zirconacyclopentenes and zirconcyclopentanes affords carbocyclic products in high yields via an unusual rearrangement that probably involves addition of an organolithium species to the β-position of a zirconium-alkyne complex to give an alkenylidene-zirconate species. A wide variety of cyclopentanoid organic structures are rapidly assembled in good yield using this multicomponent coupling. The main side reaction, which becomes exclusive in some cases, is β-hydride elimination of an intermediate cyclopentyl- or cyclopentenyl zirconocene., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: The neuroplastic pathway, which includes cyclic adenosine monophosphate response element-binding protein 1 (CREB1), brain-derived neurotrophic factor (BDNF), and its receptor (neurotrophic tyrosine kinase receptor, type 2 [NTRK2]), plays a crucial role in the adaptation of brain to stress, and thus variations of these genes are plausible risk factors for depression., Methods: A population-based sample was recruited, subsets of which were interviewed and underwent functional magnetic resonance imaging. We investigated the association of nine polymorphisms throughout the CREB1-BDNF-NTRK2 pathway with lifetime depression, rumination, current depression severity, negative life events, and sad face emotion processing in a three-level design., Results: In the population study, BDNF-rs6265 and CREB1-rs2253206 major alleles were significantly associated with rumination and through rumination with current depression severity. However, childhood adversity increased the risk of lifetime depression in the minor allele carriers of BDNF-rs6265 and CREB1-rs2253206 and in alleles of six other single nucleotide polymorphisms (SNPs). We validated our findings in the interviewed subjects using structural equation modeling. Finally, using functional magnetic resonance imaging, we found that viewing sad faces evoked greater activity in depression-related areas in healthy control subjects possessing the minor alleles of BDNF-rs6265 and CREB1-rs2253206., Conclusions: Genetic variation associated with reduced function in the CREB1-BDNF-NTRK2 pathway has multiple, sometimes opposing, influences on risk mechanisms of depression, but almost all the SNPs studied amplified the effect of childhood adversity. The use of cognitive and neural intermediate phenotypes together with a molecular pathway approach may be critical to understanding how genes influence risk of depression., (Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Background: Negative biases in emotional processing are well recognised in people who are currently depressed but are less well described in those with a history of depression, where such biases may contribute to vulnerability to relapse., Aims: To compare accuracy, discrimination and bias in face emotion recognition in those with current and remitted depression., Method: The sample comprised a control group (n = 101), a currently depressed group (n = 30) and a remitted depression group (n = 99). Participants provided valid data after receiving a computerised face emotion recognition task following standardised assessment of diagnosis and mood symptoms., Results: In the control group women were more accurate in recognising emotions than men owing to greater discrimination. Among participants with depression, those in remission correctly identified more emotions than controls owing to increased response bias, whereas those currently depressed recognised fewer emotions owing to decreased discrimination. These effects were most marked for anger, fear and sadness but there was no significant emotion × group interaction, and a similar pattern tended to be seen for happiness although not for surprise or disgust. These differences were confined to participants who were antidepressant-free, with those taking antidepressants having similar results to the control group., Conclusions: Abnormalities in face emotion recognition differ between people with current depression and those in remission. Reduced discrimination in depressed participants may reflect withdrawal from the emotions of others, whereas the increased bias in those with a history of depression could contribute to vulnerability to relapse. The normal face emotion recognition seen in those taking medication may relate to the known effects of antidepressants on emotional processing and could contribute to their ability to protect against depressive relapse.

Both reduced serotonergic (5-HT) function and negative emotional biases have been associated with vulnerability to depression. In order to investigate whether these might be related we examined 5-HT modulation of affective processing in 14 remitted depressed subjects compared with 12 never depressed controls matched for age and sex. Participants underwent function magnetic resonance imaging (fMRI) during a covert face emotion task with and without intravenous citalopram (7.5mg) pretreatment. Compared with viewing neutral faces, and irrespective of group, citalopram enhanced left anterior cingulate blood oxygen level dependent (BOLD) response to happy faces, right posterior insula and right lateral orbitofrontal responses to sad faces, and reduced amygdala responses bilaterally to fearful faces. In controls, relative to remitted depressed subjects, citalopram increased bilateral hippocampal responses to happy faces and increased right anterior insula response to sad faces. These findings were not accounted for by changes in BOLD responses to viewing neutral faces. These results are consistent with previous findings showing 5-HT modulation of affective processing; differences found in previously depressed participants compared with controls may contribute to emotional processing biases underlying vulnerability to depressive relapse., (Copyright © 2010 Elsevier B.V. and ECNP. All rights reserved.)

The serotonergic system has been widely implicated in stress related psychiatric disorders such as depression and anxiety. We investigated the possible association between depression and anxiety scores and SNPs within the HTR1A and HTR1B genes in a population sample (n=1387). There was no direct SNP-phenotype association, but in interaction with recent stressful life events rs6295 G, rs878567 T alleles and rs6296 C alleles were associated with significantly higher symptom scores. A subset of control subjects (n=101) took part in a computerised face emotion processing task. Healthy rs6295 GG carriers did not show an affective bias to perceive more negative emotions but reacted more quickly to fearful faces. Thus we conclude that the serotonin-1A receptor conveys vulnerability to these psychiatric disorders by modulating threat-related information processing. Our results extend previous findings of an interaction between stressful life events and the serotonin transporter gene to two other genes in the serotonergic pathway and emphasise the possible role of increased threat-related information processing as an intermediate phenotype., (Copyright © 2010 Elsevier B.V. and ECNP. All rights reserved.)

Humans have evolved with oral exposure to dietary microparticles and nanoparticles as a normal occurrence but the ever-growing exploitation of nanotechnology is likely to increase exposure further, both qualitatively and quantitatively. Moreover, unlike the situation with respirable particles, relatively little is known about gastrointestinal intake and handling of nanoparticles. With a long term interest in gut exposure and responses to dietary microparticles, our group is now applying its expertise to nanoparticles in the gastrointestinal tract. Here we aim to address (i) the current challenges associated with the characterisation of particle-host or particle-cell interactions, (ii) the origin and mechanisms of uptake of particles in the gastrointestinal tract, especially via the Peyer's patch and (iii) potential cellular effects of nanoparticles in the generation of reactive oxygen species and inflammasome activation, or microparticles in their adjuvant activity in pro-inflammatory signalling and immune responsiveness., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Decision making, choosing the best option from the possible outcomes, is impaired in many psychiatric conditions including affective disorders. We tested the hypothesis that variations in serotonergic genes (TPH2, TPH1, SLC6A4, HTR1A), which influence serotonin availability, affect choice behavior in a probabilistic gambling task. A population cohort (N=1035) completed a paper-and-pencil gambling task, filled out personality and symptom questionnaires and gave consent for the use of their DNA in a genetic association study. A subgroup of subjects (N=69) also completed a computer version of the task. The gambling task was designed to estimate an individual's tendency to take a risk when choosing between a smaller but more certain 'win' and a larger, less probable one. We genotyped seven haplotype tagging SNPs in the TPH2 gene, and previously reported functional polymorphisms from the other genes (rs1800532, 5HTTLPR, and rs6295). Carriers of the more prevalent TPH2 haplotype, which was previously associated with less active enzyme variant, showed reduced risk taking on both tasks compared with subjects not carrying the common haplotype. The effect of TPH2 haplotypes on risk-taking was independent of current depression and anxiety symptoms, neuroticism and impulsiveness scores. We did not find an association between functional polymorphisms in the TPH1, SLC6A4, HTR1A genes and risk-taking behavior. In conclusion, our study demonstrates the role of the TPH2 gene and the serotonin system in risk taking and suggests that TPH2 gene may contribute to the expression of psychiatric phenotypes through altered decision making.

Purpose: The aim of this study was to evaluate (1) the use of generalized equivalent uniform dose (gEUD) to optimize dose escalation of lung tumors when the esophagus overlaps the planning target volume (PTV) and (2) the potential benefit of further dose escalation in only the part of the PTV that does not overlap the esophagus., Methods and Materials: The treatment-planning computed tomography (CT) scans of patients with primary lung tumors located in different regions of the left and right lung were used for the optimization of beamlet intensity modulated radiation therapy (IMRT) plans. In all cases, the PTV overlapped part of the esophagus. The dose in the PTV was maximized according to 7 different primary cost functions: 2 plans that made use of mean dose (MD) (the reference plan, in which the 95% isodose surface covered the PTV and a second plan that had no constraint on the minimum isodose), 3 plans based on maximizing gEUD for the whole PTV with ever increasing assumptions for tumor aggressiveness, and 2 plans that used different gEUD values in 2 simultaneous, overlapping target volumes (the whole PTV and the PTV minus esophagus). Beam arrangements and NTCP-based costlets for the organs at risk (OARs) were kept identical to the original conformal plan for each case. Regardless of optimization method, the relative ranking of the resulting plans was evaluated in terms of the absence of cold spots within the PTV and the final gEUD computed for the whole PTV., Results: Because the MD-optimized plans lacked a constraint on minimum PTV coverage, they resulted in cold spots that affected approximately 5% of the PTV volume. When optimizing over the whole PTV volume, gEUD-optimized plans resulted in higher equivalent uniform PTV doses than did the reference plan while still maintaining normal-tissue constraints. However, only under the assumption of extremely aggressive tumors could cold spots in the PTV be avoided. Generally, high-level overall results are obtained when optimization in the whole PTV is also associated with a second simultaneous optimization in the PTV minus overlapping portions of the esophagus., Conclusions: Intensity modulated radiation therapy optimizations that utilize gEUD-based cost functions for the PTV and NTCP-based constraints for the OARs result in increased doses to large portions of the PTV in cases where the PTV overlaps the esophagus, while still maintaining (and confining to the overlap region) minimum dose coverage equivalent to the homogeneous PTV optimization cases.

Purpose: To investigate whether intensity-modulated radiotherapy (IMRT), optimized using the generalized equivalent uniform dose (gEUD) and normal tissue complication probability (NTCP) models, can increase the safe dose to intrahepatic tumors compared with three-dimensional conformal RT (3D-CRT). A secondary objective was to investigate the optimal beam arrangement for liver IMRT plans., Methods and Materials: Planning CT data of 15 patients with intrahepatic tumors, previously treated with 3D-CRT, were used as input. The dose delivered using 3D-CRT had been limited either by tolerance of adjacent organs, which were close to, or overlapped with, the planning target volume (PTV; overlap cases, n = 8), or liver toxicity (nonoverlap, n = 7). IMRT plans were created using the gEUD to maximize the dose across the PTV and the NTCP to maintain the organ-at-risk toxicity to that of the conformal plan. Increased heterogeneity was allowed across the PTV in overlap cases, without compromising the minimal PTV dose of the conformal plan and restricting the maximal dose to within 110% of the mean. Three different beam arrangements were used for each case: seven-field equidistant axial, six-field noncoplanar (predominantly right-sided beams), and a reproduction of the conformal gantry angles. gEUDs were also computed and used for evaluation of the plans (regardless of planning technique) to reflect the response of both high- and low-grade tumors. The IMRT plan that allowed the greatest gEUD across the PTV was used in the comparison with the 3D-CRT plan., Results: The use of IMRT significantly increased the maximal gEUD achievable across the PTV compared with the 3D-CRT plans. This was the case for the assumptions of both high- and low-grade tumors, irrespective of the tumor position within the liver. The mean gEUD increase was 11 Gy (high grade) and 18.0 Gy (low grade) for overlap cases (p = 0.001 and p = 0.003, respectively) and 10 Gy for nonoverlap cases (p = 0.020). When comparing the IMRT beam arrangements, gEUDs were considered equivalent if they differed by less than one fraction (1.5 Gy). In overlap cases (n = 8), an equivalent "best" gEUD value was obtained in 3, 5, and 7 cases for the original conformal angle, seven-field axial, and six-field noncoplanar plan, respectively. The corresponding results were 5, 2, and 3 in the cases without an overlap (n = 7)., Conclusion: We have successfully used mathematical/biologic models directly as cost functions within the optimizing process to produce IMRT plans that maximize the gEUD while maintaining compliance with a well-defined protocol for the treatment of intrahepatic cancer. For both PTV-organ-at-risk overlap and nonoverlap situations, IMRT has the capacity to improve the maximal dose achievable across the PTV, expressed in terms of the gEUD. The use of multiple noncoplanar beams appears to confer an advantage over fewer beams in cases with PTV-organ-at-risk overlap. When liver toxicity is the dose-limiting factor, high gEUD values are obtained most frequently when the field arrangement is chosen to provide the shortest possible transhepatic path length.

Computed tomography (CT) scanning is the main imaging modality utilised for planning radical oesophageal radiotherapy. Endoscopic ultrasound allows accurate localisation and local staging of oesophageal tumours. A method of incorporating this information into the CT planning process is described. Gross tumour volume position changes that occur when using this technique are presented.

We have investigated the response dynamics of the estrogen-dependent genes vitellogenin (VTG) and the vitelline envelope proteins (VEPs) as well as circulating VTG in immature female rainbow trout (Oncorhynchus mykiss) exposed to 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) for periods of 7 and 14 d. Gene responses were quantified by measurement of messenger RNA (mRNA) in liver extracts using a chemiluminescent hybridization protection assay. Circulating VTG was measured by a homologous enzyme-linked immunosorbent assay. Exposure to both E2 and EE2 induced concentration-dependent increases in all biomarkers. The data presented indicate that VEP genes may be more sensitive to estrogens than the VTG gene. The biomarker lowest-observed-effect concentrations (biomarkerLOEC) in the 14-d study with E2 were 14 ng/L (VTG protein, VTG mRNA, VEPbeta, and VEPgamma) or 4.8 ng/L (VEPalpha). The EE2 was 5- to 66-fold more potent depending on the biomarker studied. In the 7-d study, all biomarkers were elevated after 48-h exposure to E2, with biomarkerLOECs of 30 ng/L (VTG protein, VTG mRNA, and VEPgamma) or 9.7 ng/L (VEPalpha and VEPbeta). Vitellogenin mRNA was induced up to 1,000-fold above baseline, and this translated into an increase of approximately 50,000-fold in circulating VTG. In conclusion, all biomarkers responded to estrogen exposure at environmentally relevant concentrations.

We have developed a novel test system for the quantitative assessment of gene transcription. The procedure involves the use of chemiluminescent-labeled oligonucleotide probes in a hybridization protection assay (HPA) format. We have used this technology to measure changes in vitellogenin mRNA to demonstrate the impact of estrogen exposure in the juvenile fathead minnow (Pimephales promelas). Marked changes in mRNA expression were observed in response to intraperitoneal injection of 17beta-estradiol demonstrating the utility of this technique for the identification and monitoring of toxic responses to xenobiotics.