Quantifying dimensional severity of obsessive-compulsive disorder for neurobiological research

Current research to explore genetic susceptibility factors in obsessive-compulsive disorder (OCD) has resulted in the tentative identification of a small number of genes. However, findings have not been readily replicated. It is now broadly accepted that a major limitation to this work is the heterogeneous nature of this disorder, and that an approach incorporating OCD symptom dimensions in a quantitative manner may be more successful in identifying both common as well as dimension-specific vulnerability genetic factors. As most existing genetic datasets did not collect specific dimensional severity ratings, a specific method to reliably extract dimensional ratings from the most widely used severity rating scale, the Yale-Brown Obsessive Compulsive Scale (YBOCS), for OCD is needed. This project aims to develop and validate a novel algorithm to extrapolate specific dimensional symptom severity ratings in OCD from the existing YBOCS for use in genetics and other neurobiological research. To accomplish this goal, we used a large data set comprising adult subjects from three independent sites: the Brazilian OCD Consortium, the Sunnybrook Health Sciences Centre in Toronto, Canada and the Hospital of Bellvitge, in Barcelona, Spain. A multinomial logistic regression was proposed to model and predict the quantitative phenotype [i.e., the severity of each of the five homogeneous symptom dimensions of the Dimensional YBOCS (DYBOCS)] in subjects who have only YBOCS (categorical) data. YBOCS and DYBOCS data obtained from 1183 subjects were used to build the model, which was tested with the leave-one-out cross-validation method. The model's goodness of fit, accepting a deviation of up to three points in the predicted DYBOCS score, varied from 78% (symmetry/order) to 84% (cleaning/contamination and hoarding dimensions). These results suggest that this algorithm may be a valuable tool for extracting dimensional phenotypic data for neurobiological studies in OCD.

Significant Locus and Metabolic Genetic Correlations Revealed in Genome-Wide Association Study of Anorexia Nervosa

OBJECTIVE

The authors conducted a genome-wide association study of anorexia nervosa and calculated genetic correlations with a series of psychiatric, educational, and metabolic phenotypes.

METHOD

Following uniform quality control and imputation procedures using the 1000 Genomes Project (phase 3) in 12 case-control cohorts comprising 3,495 anorexia nervosa cases and 10,982 controls, the authors performed standard association analysis followed by a meta-analysis across cohorts. Linkage disequilibrium score regression was used to calculate genome-wide common variant heritability (single-nucleotide polymorphism [SNP]-based heritability [h²_SNP]), partitioned heritability, and genetic correlations (r_g) between anorexia nervosa and 159 other phenotypes.

RESULTS

Results were obtained for 10,641,224 SNPs and insertion-deletion variants with minor allele frequencies >1% and imputation quality scores >0.6. The h²_SNP of anorexia nervosa was 0.20 (SE=0.02), suggesting that a substantial fraction of the twin-based heritability arises from common genetic variation. The authors identified one genome-wide significant locus on chromosome 12 (rs4622308) in a region harboring a previously reported type 1 diabetes and autoimmune disorder locus. Significant positive genetic correlations were observed between anorexia nervosa and schizophrenia, neuroticism, educational attainment, and high-density lipoprotein cholesterol, and significant negative genetic correlations were observed between anorexia nervosa and body mass index, insulin, glucose, and lipid phenotypes.

CONCLUSIONS

Anorexia nervosa is a complex heritable phenotype for which this study has uncovered the first genome-wide significant locus. Anorexia nervosa also has large and significant genetic correlations with both psychiatric phenotypes and metabolic traits. The study results encourage a reconceptualization of this frequently lethal disorder as one with both psychiatric and metabolic etiology.

Elucidation of photocatalysis, photoluminescence and antibacterial studies of ZnO thin films by spin coating method

The ZnO thin films have been prepared by spin coating followed by annealing at different temperatures like 300°C, 350°C, 400°C, 450°C, 500°C & 550°C and ZnO nanoparticles have been used for photocatalytic and antibacterial applications. The morphological investigation and phase analysis of synthesized thin films well characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Photoluminescence (PL), Transmission Electron Microscopy (TEM) and Raman studies. The luminescence peaks detected in the noticeable region between 350nm to 550nm for all synthesized nanosamples are associated to the existence of defects of oxygen sites. The luminescence emission bands are observed at 487nm (blue emission), and 530nm (green emission) at the RT. It is observed that there are no modification positions of PL peaks in all ZnO nanoparticles. In the current attempt, the synthesized ZnO particles have been used photocatalytic and antibacterial applications. The antibacterial activity of characterized samples was regulated using different concentrations of synthesized ZnO particles (100μg/ml, 200μg/ml, 300μg/ml, 400μg/ml, 500μg/ml and 600μg/ml) against gram positive and gram negative bacteria (S. pnemoniae, S. aureus, E. coli and E. hermannii) using agar well diffusion assay. The increase in concentration, decrease in zone of inhibition. The prepared ZnO morphologies showed photocatalytic activity under the sunlight enhancing the degradation rate of Rhodamine-B (RhB), which is one of the common water pollutant released by textile and paper industries.

Impact of automated ICA-based denoising of fMRI data in acute stroke patients

Different strategies have been developed using Independent Component Analysis (ICA) to automatically de-noise fMRI data, either focusing on removing only certain components (e.g. motion-ICA-AROMA, Pruim et al., 2015a) or using more complex classifiers to remove multiple types of noise components (e.g. FIX, Salimi-Khorshidi et al., 2014 Griffanti et al., 2014). However, denoising data obtained in an acute setting might prove challenging: the presence of multiple noise sources may not allow focused strategies to clean the data enough and the heterogeneity in the data may be so great to critically undermine complex approaches. The purpose of this study was to explore what automated ICA based approach would better cope with these limitations when cleaning fMRI data obtained from acute stroke patients. The performance of a focused classifier (ICA-AROMA) and a complex classifier (FIX) approaches were compared using data obtained from twenty consecutive acute lacunar stroke patients using metrics determining RSN identification, RSN reproducibility, changes in the BOLD variance, differences in the estimation of functional connectivity and loss of temporal degrees of freedom. The use of generic-trained FIX resulted in misclassification of components and significant loss of signal (< 80%), and was not explored further. Both ICA-AROMA and patient-trained FIX based denoising approaches resulted in significantly improved RSN reproducibility (p < 0.001), localized reduction in BOLD variance consistent with noise removal, and significant changes in functional connectivity (p < 0.001). Patient-trained FIX resulted in higher RSN identifiability (p < 0.001) and wider changes both in the BOLD variance and in functional connectivity compared to ICA-AROMA. The success of ICA-AROMA suggests that by focusing on selected components the full automation can deliver meaningful data for analysis even in population with multiple sources of noise. However, the time invested to train FIX with appropriate patient data proved valuable, particularly in improving the signal-to-noise ratio.

An unusual case of Escherichia coli O157:H7 infection with pseudomembranous colitis-like lesions associated with haemolytic-uraemic syndrome and neurological sequelae

A 75-year-old man was admitted with abdominal pain and fresh rectal bleeding. Significantly, he had no risk factors for Clostridium difficile infection. An abdominal CT demonstrated colonic thickening, and flexible sigmoidoscopy identified pseudomembranous colitis-like lesions. After initial treatment as C. difficile colitis, a stool sample revealed Escherichia coli O157:H7 infection. Antibiotic therapy was stopped due to the risk of lysis-mediated toxin release, but unfortunately, the patient continued to deteriorate. He developed several of the severe sequelae of E. coli O157:H7 infection, including haemolytic-uraemic syndrome with an acute kidney injury necessitating haemofiltration, plus progressively severe seizures requiring escalating antiepileptic treatment and intubation for airway protection. After a prolonged intensive care admission and subsequent recovery on the ward, our patient was discharged alive.

Characterisation of polyamide 11/copper antimicrobial composites for medical device applications

Direct incorporation of antimicrobial additive into the polymer matrix is a cost effective approach for the development of polymer/metal antimicrobial composites. Application of these antimicrobial composite systems for manufacturing medical devices addresses the issue of device related infections. In the present study, commercially available inorganic copper based additive, Plasticopper, was incorporated into a Polyamide 11(PA 11) matrix during the polymer processing stage. These polymer composites were evaluated for their morphological, mechanical, antimicrobial and ion release properties. Isothermal crystallisation studies showed that the copper additive acted as a nucleating agent and promoted faster crystallisation. Short term mechanical studies confirmed that the incorporation of copper has reinforcing effect on the composites with 5 and 10% copper loadings and did not adversely affect the short-term mechanical performance of the polymer composites. These composite systems were shown to be active against Escherichia coli ATCC 8739 with >99.99% reduction in bacterial population. Corresponding ion release profiles for these composites indicated long term antimicrobial activity.

Treatment-Resistant Schizophrenia: Treatment Response and Resistance in Psychosis (TRRIP) Working Group Consensus Guidelines on Diagnosis and Terminology

OBJECTIVE

Research and clinical translation in schizophrenia is limited by inconsistent definitions of treatment resistance and response. To address this issue, the authors evaluated current approaches and then developed consensus criteria and guidelines.

METHOD

A systematic review of randomized antipsychotic clinical trials in treatment-resistant schizophrenia was performed, and definitions of treatment resistance were extracted. Subsequently, consensus operationalized criteria were developed through 1) a multiphase, mixed methods approach, 2) identification of key criteria via an online survey, and 3) meetings to achieve consensus.

RESULTS

Of 2,808 studies identified, 42 met inclusion criteria. Of these, 21 studies (50%) did not provide operationalized criteria. In the remaining studies, criteria varied considerably, particularly regarding symptom severity, prior treatment duration, and antipsychotic dosage thresholds; only two studies (5%) utilized the same criteria. The consensus group identified minimum and optimal criteria, employing the following principles: 1) current symptoms of a minimum duration and severity determined by a standardized rating scale; 2) moderate or worse functional impairment; 3) prior treatment consisting of at least two different antipsychotic trials, each for a minimum duration and dosage; 4) systematic monitoring of adherence and meeting of minimum adherence criteria; 5) ideally at least one prospective treatment trial; and 6) criteria that clearly separate responsive from treatment-resistant patients.

CONCLUSIONS

There is considerable variation in current approaches to defining treatment resistance in schizophrenia. The authors present consensus guidelines that operationalize criteria for determining and reporting treatment resistance, adequate treatment, and treatment response, providing a benchmark for research and clinical translation.

Abstract P5-15-05: Randomized phase II study evaluating different schedules of nab-paclitaxel in metastatic breast cancer (MBC): Results of the SNAP study

Background

Longer chemotherapy (CT) duration is associated with a significant improvement in progression-free survival (PFS) and a moderate, but significant improvement in overall survival (OS) in MBC patients (pts). Prolonged CT administration, however, must be weighed against the side effects of continuous CT delivery. The SNAP trial was designed to improve the tolerability of prolonged CT by studying alternative treatment schedules.

Methods

The SNAP trial enrolled 258 women from April 2013 to Aug 2015. Eligibility criteria included HER2- MBC, no prior CT for advanced disease, measurable and/or non-measurable disease.

All eligible pts were randomized to one of three arms. Pts received the same induction chemotherapy consisting of 3 cycles of nab-Paclitaxel given days 1,8,15 Q28, followed by one of the three maintenance therapy schedules. Originally, the dose of the induction chemotherapy was 150 mg/m2, but this was reduced to 125 mg/m2 following the first safety review of 48 treated pts. The three schedules of nab-Paclitaxel used as maintenance therapy were (Arm A) nab-Paclitaxel 150 mg/m2 d 1,15 Q28; (Arm B) nab-Paclitaxel 100 mg/m2 d 1,8,15 Q28; (Arm C) nab-Paclitaxel 75 mg/m2 d 1,8,15,22 Q28.

The primary objective is to evaluate the efficacy of three nab-Paclitaxel regimens as measured by progression-free survival (PFS), using the historical reference of PFS (based on AVADO study) of docetaxel for first-line treatment of metastatic breast cancer. Each of the three regimens is compared to the historic 7-month median PFS to determine whether any of the three regimens are worthy of further investigation. Secondary endpoints include tolerability, feasibility, response rate, OS and QoL.

Results

Two-hundred-fifty-eight pts have been randomised and 255 are available for primary endpoint evaluation. At 18.2 months' median follow-up, 182 PFS events and 85 deaths have been observed. Median PFS was 7.9 months (90%CI 6.8-8.4) in Arm A, 9.0 months (90%CI 8.1-10.9) in Arm B and 8.5 (90%CI 6.7-9.5) in Arm C. PFS in Arm B was significantly longer than the historic PFS of first-line docetaxel (one-sided log-rank p=0.03).

As expected, neurotoxicity was the most frequent adverse event. In the induction phase, grade≥2 sensory neuropathy was reported in 14.8% of pts at the starting dose of 150 mg/m2 and 7.5% at the starting dose of 125 mg/m2; grade≥3 sensory neuropathy occurred in 2.5% and 0% of the pts, respectively. In the maintenance phase, grade≥2 sensory neuropathy was reported in 37.9% of pts in Arm A, 36.1% in Arm B and 31.2% in Arm C; grade≥3 sensory neuropathy occurred in 9.1%, 5.6% and 6.6% of the pts, respectively.

199 pts started the maintenance phase. The median number of maintenance cycles was 3, 4, and 5, respectively. Stopping maintenance for reasons other than objective progression occurred in 41%, 58%, and 53%, respectively.

Conclusion

The SNAP trial indicates that alternative maintenance chemotherapy schedules with reduced doses after a short term induction phase at conventional doses are feasible and significantly more active than the historical PFS of docetaxel in the first line treatment of advanced breast cancer.

Citation Format: Gennari A, Sun Z, Hasler-Strub U, Colleoni M, Kennedy J, von Moos R, Cortes J, Vidal M, Hennessy B, Walshe J, Amillano Parraga K, Morales Murrillo S, Pagani O, Barbeaux A, Borstnar S, Rabaglio M, Maibach R, Regan MM, Jerusalem G. Randomized phase II study evaluating different schedules of nab-paclitaxel in metastatic breast cancer (MBC): Results of the SNAP study [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 P5-15-05.

Abstract TP44: Quantifying Edema in Acute Stroke

Introduction: The Acute Stroke Imaging Roadmap III identifies structural distortion due to vasogenic edema and hemorrhage as a research priority for defining final infarction. Non-linear registration (NLR) of a follow up scan to an undistorted presenting scan could correct for distortions due to edema, hemorrhage or atrophy, achieving this goal. In addition, the difference between the volume of infarction following NLR and the volume following a rigid body registration (RBR) reflects the degree of anatomical distortion. In this study we evaluate this technique to correct for subacute edema at different timepoints, and generate a metric to quantify brain swelling at these times. We determine whether early edema at 24 hours predicts edema at 1 week.

Methods: Patients with non-lacunar ischemic stroke were recruited into a MRI study. Patients had structural T1-weighted, T2-weighted FLAIR and diffusion-weighted imaging (DWI, b=1000/0) at presentation, 24hrs, 1wk and 1mo. Infarction was defined manually at 24hrs using DWI, and at 1wk and 1mo using FLAIR image by 2 raters. To quantify edema, both NLR warps and RBR matrices were generated between the T1 images at each timepoint to the presenting T1 scan. Infarct masks were transformed to presenting image space using RBR and NLR, and the relative difference in volumes used to quantify the Edema Metric (EM).

Results: 34 patients were recruited into the study. NLR corrected for distortions due to edema and hemorrhagic transformation at the 24hr and 1wk timepoints. The EM at 24 hours, 1 week and 1 month were 17.7% (p=0.009), 26.5% (p=0.02), and 7.1% (p=0.05) respectively for the manually defined infarct masks. EM at 24 hours predicted edema at 1 week (r 2 =37%, p=0.009), but not at 1 month (r 2 =3%, p=0.6).

Conclusions: NLR provides an opportunity to correct for edema at subacute timepoints and by comparing infarct volumes to those following RBR provides a measure of edema. The EM quantifies the contribution of edema at 24hrs and 1wk, and potentially allows the selection of patients at 24hrs who are likely to develop significant swelling at 1 week. The EM may also be useful in stroke trials to quantify the effect sizes of treatments aimed at minimizing edema in stroke.

Optimizing image registration and infarct definition in stroke research

OBJECTIVE

Accurate representation of final infarct volume is essential for assessing the efficacy of stroke interventions in imaging-based studies. This study defines the impact of image registration methods used at different timepoints following stroke, and the implications for infarct definition in stroke research.

METHODS

Patients presenting with acute ischemic stroke were imaged serially using magnetic resonance imaging. Infarct volume was defined manually using four metrics: 24-h b1000 imaging; 1-week and 1-month T2-weighted FLAIR; and automatically using predefined thresholds of ADC at 24 h. Infarct overlap statistics and volumes were compared across timepoints following both rigid body and nonlinear image registration to the presenting MRI. The effect of nonlinear registration on a hypothetical trial sample size was calculated.

RESULTS

Thirty-seven patients were included. Nonlinear registration improved infarct overlap statistics and consistency of total infarct volumes across timepoints, and reduced infarct volumes by 4.0 mL (13.1%) and 7.1 mL (18.2%) at 24 h and 1 week, respectively, compared to rigid body registration. Infarct volume at 24 h, defined using a predetermined ADC threshold, was less sensitive to infarction than b1000 imaging. 1-week T2-weighted FLAIR imaging was the most accurate representation of final infarct volume. Nonlinear registration reduced hypothetical trial sample size, independent of infarct volume, by an average of 13%.

INTERPRETATION

Nonlinear image registration may offer the opportunity of improving the accuracy of infarct definition in serial imaging studies compared to rigid body registration, helping to overcome the challenges of anatomical distortions at subacute timepoints, and reducing sample size for imaging-based clinical trials.

The Drosophila foraging gene human orthologue PRKG1 predicts individual differences in the effects of early adversity on maternal sensitivity

There is variation in the extent to which childhood adverse experience affects adult individual differences in maternal behavior. Genetic variation in the animal foraging gene, which encodes a cGMP-dependent protein kinase, contributes to variation in the responses of adult fruit flies, Drosophila melanogaster, to early life adversity and is also known to play a role in maternal behavior in social insects. Here we investigate genetic variation in the human foraging gene (PRKG1) as a predictor of individual differences in the effects of early adversity on maternal behavior in two cohorts. We show that the PRKG1 genetic polymorphism rs2043556 associates with maternal sensitivity towards their infants. We also show that rs2043556 moderates the association between self-reported childhood adversity of the mother and her later maternal sensitivity. Mothers with the TT allele of rs2043556 appeared buffered from the effects of early adversity, whereas mothers with the presence of a C allele were not. Our study used the Toronto Longitudinal Cohort (N=288 mother-16 month old infant pairs) and the Maternal Adversity and Vulnerability and Neurodevelopment Cohort (N=281 mother-18 month old infant pairs). Our findings expand the literature on the contributions of both genetics and gene-environment interactions to maternal sensitivity, a salient feature of the early environment relevant for child neurodevelopment.

Quantification of Serial Cerebral Blood Flow in Acute Stroke Using Arterial Spin Labeling

Supplemental Digital Content is available in the text.

Background and Purpose—

Perfusion-weighted imaging is used to select patients with acute ischemic stroke for intervention, but knowledge of cerebral perfusion can also inform the understanding of ischemic injury. Arterial spin labeling allows repeated measurement of absolute cerebral blood flow (CBF) without the need for exogenous contrast. The aim of this study was to explore the relationship between dynamic CBF and tissue outcome in the month after stroke onset.

Methods—

Patients with nonlacunar ischemic stroke underwent ≤5 repeated magnetic resonance imaging scans at presentation, 2 hours, 1 day, 1 week, and 1 month. Imaging included vessel-encoded pseudocontinuous arterial spin labeling using multiple postlabeling delays to quantify CBF in gray matter regions of interest. Receiver–operator characteristic curves were used to predict tissue outcome using CBF. Repeatability was assessed in 6 healthy volunteers and compared with contralateral regions of patients. Diffusion-weighted and T2-weighted fluid attenuated inversion recovery imaging were used to define tissue outcome.

Results—

Forty patients were included. In contralateral regions of patients, there was significant variation of CBF between individuals, but not between scan times (mean±SD: 53±42 mL/100 g/min). Within ischemic regions, mean CBF was lowest in ischemic core (17±23 mL/100 g/min), followed by regions of early (21±26 mL/100 g/min) and late infarct growth (25±35 mL/100 g/min; ANOVA P<0.0001). Between patients, there was marked overlap in presenting and serial CBF values.

Conclusions—

Knowledge of perfusion dynamics partially explained tissue fate. Factors such as metabolism and tissue susceptibility are also likely to influence tissue outcome.

Ectopic miR-125a Expression Induces Long-Term Repopulating Stem Cell Capacity in Mouse and Human Hematopoietic Progenitors

Umbilical cord blood (CB) is a convenient and broadly used source of hematopoietic stem cells (HSCs) for allogeneic stem cell transplantation. However, limiting numbers of HSCs remain a major constraint for its clinical application. Although one feasible option would be to expand HSCs to improve therapeutic outcome, available protocols and the molecular mechanisms governing the self-renewal of HSCs are unclear. Here, we show that ectopic expression of a single microRNA (miRNA), miR-125a, in purified murine and human multipotent progenitors (MPPs) resulted in increased self-renewal and robust long-term multi-lineage repopulation in transplanted recipient mice. Using quantitative proteomics and western blot analysis, we identified a restricted set of miR-125a targets involved in conferring long-term repopulating capacity to MPPs in humans and mice. Our findings offer the innovative potential to use MPPs with enhanced self-renewal activity to augment limited sources of HSCs to improve clinical protocols.

Comparison of parental estimate of developmental age with measured IQ in children with neurodevelopmental disorders

BACKGROUND

Formal IQ tests are an important part of the diagnostic and needs-based assessment process for children with neurodevelopmental disorders. However, resources for such assessments are not always available. It has been suggested that parental estimates of their child's developmental age could serve as a proxy IQ when formal measures are unavailable.

METHOD

Parental estimates of their child's developmental age were converted to a developmental quotient (DQ) in 197 children with Autism Spectrum Disorder (ASD) aged 4-9 years, and 108 children with ADHD and intellectual disability (ADHD + ID) aged 7-15 years. Formal IQ assessments were then conducted. Parents completed the Social Communication Questionnaire ((SCQ), a measure of autism symptomatology) and a demographic questionnaire.

RESULTS

In the ASD sample, 58% of parent estimates were within 15 points (i.e. one standard deviation) of the child's measured IQ score. Lower measured IQ and lower SCQ total score predicted higher parental accuracy. In the ADHD + ID sample, 74% of parental estimates were within 15 points of measured IQ. In this group, higher child IQ predicted greater parental accuracy. Parents in the ADHD + ID group were more likely to overestimate children's ability level than parents in the ASD group.

CONCLUSIONS

In this study, the majority of parents of children with ADHD and ID were able to estimate their child's intellectual ability level with some accuracy. Parents of children with ASD were less accurate, but this may be because these parents were focussing more on children's level of adaptive functioning, which is known to be typically lower than cognitive ability in ASD.

Mediating the cultural boundaries between medicine, nursing and management - the central challenge in hospital reform

This paper documents the resilience of medical and nursing profession-based subcultures and the extent of the differences between them. Against this background, we assess the capacity and willingness of medical and nursing managers to promote changes that will extend the accountability of clinicians and engender more evidence-based, financially driven and output-oriented approaches to service delivery.

Abstract 63: Novel Imaging of Protein Integrity to Better Define Ischemic Injury After Stroke

Introduction: Ischemic injury on MRI is defined acutely by measuring the diffusion of water alone. Chemical exchange saturation transfer imaging (CEST) allows measurement of intracellular pH, and changes in protein structure and mobility using Nuclear Overhauser Enhancement (NOE). When identifying treatment targets, changes to protein integrity have the potential to complement diffusion-weighted imaging (DWI) in distinguishing irreversible from reversible intracellular processes that are amenable to therapeutic intervention.

Methods: Patients with non-lacunar ischemic stroke underwent serial MRI over 1 month. The imaging protocol included single slice CEST imaging. NOE was quantified using a 3-pool exchange model relative to the contralateral hemisphere (rNOE*). DWI, ASL perfusion imaging, T1-weighted and FLAIR imaging were used to define the tissue outcome: ischemic core, infarct growth, and oligemic tissue that survived. Infarct growth was classified as early or late (before or after 24 hours). Images and masks were registered to CEST native image space for voxelwise and patient-level serial analyses.

Results: 30 patients were included in the analysis. Within 6 hours rNOE* in early infarct growth was significantly lower than ischemic core and late infarct growth (p<0.001 and p<0.001, see Figure). In patient-level analyses, rNOE* dropped over the initial 24 hours in the ischemic core and early infarct growth regions, but not in regions of late infarct growth or oligemia.

Conclusion: rNOE* showed a discrete temporal profile in tissue that infarcted by 24 hours in contrast to that which survived or infarcted later. This is additive information to that provided by routine acute stroke MRI at presentation, and demonstrates that the imaging of intracellular protein structure and mobility may have a role alongside DWI in helping to predict tissue fate. Further work is required to understand the potential of NOE as a modifiable imaging biomarker.

John Porter Lecture: Liberal Nationalisms Revisited

Liberal Nationalisms: Empire, State and Civil Society in Scotland and Quebec argues that the emergence and character of nationalism are directly related to changes in patterns of political rule and the liberal settlements that underlay that rule. The focus is on the emergence of two nationalist groups in Scotland and Quebec at the beginning of the twentieth century: the Young Scots' Society and Ligue nationaliste canadienne. They exhibited liberal nationalisms differently (1) in response to the British Empire's predatory imperial policies, (2) in the perception that their states had failed to effectively accommodate the Scottish and French Canadian nations, and more problematically (3) on the place of organized religion in civil society. Their responses suggest the emergence of two quite distinct liberal nationalisms: one in which the emphasis was on universal individual rights, and the other in which particular group rights were more clearly favored. The article offers some further reflection on the relationship between nationalism and liberalism, specifically on the existence of a symbiotic relationship and more generally that liberalism is successful when embedded in nationalism.

Emergency General Surgery: evolution of a subspecialty by stealth

BACKGROUND

Emergency surgical patients account for around half of all NHS surgical workload and 80 % of surgical deaths. Few trainees opt to CCT in General Surgery, and there is no recognised subspecialty training program in Emergency General Surgery (EGS). Despite this lack of training and relevant assessment by examination, there appears to be an increasing number of EGS posts advertised. This study aims to provide information about potential future employment opportunities for surgical trainees.

METHODS

All consultant surgeon posts, advertised in the British Medical Journal between January 2009 and December 2014 were included. Data collected included specialty, region and institute of advertised post. For the purposes of statistical analysis, data was divided into two separate year bands: 2009-2011 and 2012-2014. Statistical analysis was by Chi-squared test; p <0.01 was considered statistically significant. An online tool was also used to determine experience and attitudes towards EGS amongst Consultant members of the ASGBI and all UK trainees in national training number (NTN) posts.

RESULTS

Over the six-year study period, there were 1240 consultant job adverts in a general surgical specialty. Nine hundred and 75 were substantive posts; the region with the most jobs was London and the South East (n = 278). There were 55 jobs advertised in EGS, either with (20) or without (35) another subspecialty. The number of EGS adverts increased significantly in 2012-14 compared to 2009-11 (p = 0.008). 229 (28 %) Consultants and 309 (22 %) trainees responded to the survey. 16 % of consultants work in NHS institutions with Emergency General Surgeons. Only 21 % of trainees believe EGS will be delivered by EGS consultants in the future whilst 8.2 % of trainees stated EGS as their career plan. Less than half of all UK consultant surgeons see EGS as a subspecialty.

CONCLUSIONS

This data demonstrates increasing societal need for EGS consultants over the last six years and the emergence of Emergency Surgery as a new subspecialty. In order to meet the EGS needs of the NHS, general surgical training and the examination system need to be revised.

BDNF Val66Met polymorphism and stressful life events in melancholic childhood-onset depression

INTRODUCTION

Brain-derived neurotrophic factor (BDNF) polymorphisms have been examined for their contribution toward depression with equivocal results. More homogeneous phenotypes might be used to improve our understanding of genetic liability to depression. The aim of our study was to (a) test for an association between the BDNF Val66Met polymorphism and childhood-onset melancholic depression and (b) to examine the interactive effects of stressful life events (SLE) and the Val66Met polymorphism on the risk of childhood-onset melancholic depression.

MATERIALS AND METHODS

A total of 583 depressed probands were involved in this study (162 of the melancholic subtype). Diagnoses were derived through the Interview Schedule for Children and Adolescents - Diagnostic Version and life event data were collected using an Intake General Information Sheet.

RESULTS

Overall, 27.8% of the participants fulfilled the criteria for melancholy. In the melancholic group, the proportion of females was higher (53.1%), although there were more males in the overall depressed sample. We detected no significant differences in genotype or allele frequency between the melancholic and the nonmelancholic depressed group. The BDNF Val66Met polymorphism and SLE interaction was not significantly associated with the melancholy outcome.

CONCLUSION

In our study, females were more prone to developing the early-onset melancholic phenotype. To our knowledge, this is the first study to investigate the differentiating effect of the genotype and the G×E interaction on the melancholic phenotype in a large sample of depressed young patients. We did not find an association between the melancholic subtype of major depression and the BDNF genotype and SLE interaction in this sample, which is representative of the Hungarian clinic-referred population of depressed youths.

Synthesis and Compositional Analysis of Permalloy Powder Prepared by Arc-Discharge

We report the synthesis, compositional, structural and magnetic properties of permalloy powders prepared using an arc-discharge method under different atmospheres. Ion beam analysis results showed that powder prepared in air had a higher concentration of oxygen than those prepared under nitrogen or argon atmospheres. X-ray diffraction measurements showed that powders prepared in air contained magnetite (Fe3O4) and other phases, while powders prepared under nitrogen or argon predominately contained permalloy. The permalloy powders contained a broad range of particle sizes, and nanoparticles as small as 10 nm were evident from transmission electron microscopy data. The saturation magnetizations were significantly lower for the powders prepared in air than those prepared under nitrogen or argon. This can be attributed to oxidation, where the saturation magnetization is predominately from Fe3O4 for powders made in air. The coercive fields were also significantly larger for powders prepared in air, which is consistent with the powders containing different phases when compared with the permalloy powders. Our results show that permalloy powders can be made in nitrogen and argon, allowing for the production of low oxygen content permalloy powders for device applications. Our results also suggest that the use of an iron anode could result in Fe3O4 powders.

Pre-treatment lymphocytopaenia is an adverse prognostic biomarker in muscle-invasive and advanced bladder cancer

BACKGROUND

Pre-treatment lymphocytopaenia may result from cytokines secreted by the tumour microenvironment in association with aggressive tumour biology. We sought to establish the prognostic significance of lymphocytopaenia in muscle-invasive and advanced bladder cancer.

PATIENTS AND METHODS

Seventy-four patients with muscle-invasive bladder cancer treated with radical chemoradiotherapy and 131 patients with advanced bladder cancer treated with palliative chemotherapy were included in the study. The absolute lymphocyte count on the first day of treatment was recorded. Invasive local or systemic recurrence in the muscle-invasive bladder cancer cohort and all-cause mortality in the advanced bladder cancer cohort were defined as survival end points. Receiver operating characteristic (ROC) curve analysis was utilized to determine the cut-off for defining lymphocytopaenia in the muscle-invasive bladder cancer cohort followed by multivariable analysis in a model evaluating the following variables: anaemia, neutrophilia, tumour stage, hydronephrosis and neoadjuvant chemotherapy. Subsequently, lymphocytopaenia was assessed in a multivariable model of the advanced bladder cancer cohort analysing the following prognostic variables: neutrophilia, anaemia, performance status and presence of bone or visceral metastases. A further analysis was carried out evaluating absolute lymphocyte count as a continuous variable.

RESULTS

An absolute lymphocyte count of 1.5 × 10(9)/l was determined as the cut-off on ROC curve analysis in the muscle-invasive bladder cancer cohort, and multivariate analysis revealed that only lymphocytopaenia was predictive for inferior outcome in this cohort. In the advanced bladder cancer cohort, lymphocytopaenia [hazard ratio (HR) 1.6, 95% confidence interval (CI) 1.1-2.4; P = 0.02] and performance status (HR 1.7, 95% CI 1.0-2.7; P = 0.047) were adverse prognostic factors in the binary variable multivariate model. Absolute lymphocyte count was the sole significant factor when analysed as a continuous variable (HR 0.66, 95% CI 0.5-0.87; P = 0.003).

CONCLUSION

Pre-treatment lymphocytopaenia is an independent adverse prognostic factor in both muscle-invasive and advanced bladder cancer. It may be a manifestation of cancer-induced immune suppression driving tumour progression.

Imaging biomarkers in acute ischemic stroke trials: a systematic review

BACKGROUND AND PURPOSE

Imaging biomarkers are increasingly used to provide a better understanding of the pathophysiology of acute ischemic stroke. However, this approach of routinely using imaging biomarkers to inform treatment decisions has yet to be translated into successful randomized trials. The aim of this study was to systematically review the use of imaging biomarkers in randomized controlled trials in patients with acute ischemic stroke, exploring the purposes for which the imaging biomarkers were used.

MATERIALS AND METHODS

We performed a systematic review of imaging biomarkers used in randomized controlled trials of acute ischemic stroke, in which a therapeutic intervention was trialed within 48 hours of symptom onset. Data bases searched included MEDLINE, EMBASE, strokecenter.org, and the Virtual International Stroke Trials Archive (1995-2014).

RESULTS

Eighty-four studies met the criteria, of which 49 used imaging to select patients; 31, for subgroup analysis; and 49, as an outcome measure. Imaging biomarkers were broadly used for 8 purposes. There was marked heterogeneity in the definitions and uses of imaging biomarkers and significant publication bias among post hoc analyses.

CONCLUSIONS

Imaging biomarkers offer the opportunity to refine the trial cohort by minimizing participant variation, to decrease sample size, and to personalize treatment approaches for those who stand to benefit most. However, within imaging modalities, there has been little consistency between stroke trials. Greater effort to prospectively use consistent imaging biomarkers should help improve the development of novel treatment strategies in acute stroke and improve comparison between studies.

Identifying the ischaemic penumbra using pH-weighted magnetic resonance imaging

The original concept of the ischaemic penumbra suggested imaging of regional cerebral blood flow and metabolism would be required to identify tissue that may benefit from intervention. Amide proton transfer magnetic resonance imaging, a chemical exchange saturation transfer technique, has been used to derive cerebral intracellular pH in preclinical stroke models and has been proposed as a metabolic marker of ischaemic penumbra. In this proof of principle clinical study, we explored the potential of this pH-weighted magnetic resonance imaging technique at tissue-level. Detailed voxel-wise analysis was performed on data from a prospective cohort of 12 patients with acute ischaemic stroke. Voxels within ischaemic core had a more severe intracellular acidosis than hypoperfused tissue recruited to the final infarct (P < 0.0001), which in turn was more acidotic than hypoperfused tissue that survived (P < 0.0001). In addition, when confined to the grey matter perfusion deficit, intracellular pH (P < 0.0001), but not cerebral blood flow (P = 0.31), differed between tissue that infarcted and tissue that survived. Within the presenting apparent diffusion coefficient lesion, intracellular pH differed between tissue with early apparent diffusion lesion pseudonormalization and tissue with true radiographic recovery. These findings support the need for further investigation of pH-weighted imaging in patients with acute ischaemic stroke.

Non-invasive subcutaneous fat reduction: a review

The risks, financial costs and lengthy downtime associated with surgical procedures for fat reduction have led to the development of a number of non-invasive techniques. Non-invasive body contouring now represents the fastest growing area of aesthetic medicine. There are currently four leading non-invasive techniques for reducing localized subcutaneous adipose tissue: low-level laser therapy (LLLT), cryolipolysis, radio frequency (RF) and high-intensity focused ultrasound (HIFU). To review and compare leading techniques and clinical outcomes of non-invasive subcutaneous fat reduction. The terms 'non-invasive', 'low-level laser', 'cryolipolysis', 'ultrasound' and 'radio frequency' were combined with 'lipolysis', 'fat reduction' or 'body contour' during separate searches in the PubMed database. We identified 31 studies (27 prospective clinical studies and four retrospective chart reviews) with a total of 2937 patients that had been treated with LLLT (n = 1114), cryolipolysis (n = 706), HIFU (n = 843) or RF (n = 116) or other techniques (n = 158) for fat reduction or body contouring. A majority of these patients experienced significant and satisfying results without any serious adverse effects. The studies investigating these devices have all varied in treatment regimen, body locations, follow-up times or outcome operationalization. Each technique differs in offered advantages and severity of adverse effects. However, multiple non-invasive devices are safe and effective for circumferential reduction in local fat tissue by 2 cm or more across the abdomen, hips and thighs. Results are consistent and reproducible for each device and none are associated with any serious or permanent adverse effects.

A comparative study on the morphological features of highly ordered MgO:AgO nanocube arrays prepared via a hydrothermal method

II–VI semiconductor nanotubes are a recently developed class of nanomaterials whose unique photophysical properties are helping to create a new generation of nanomaterials in the field of photonics and microelectronics.