Sleep disruption in adolescent inpatients: prevalence, associations with clinical outcomes, and clinician perspectives

Sleep problems are common for adolescents with psychiatric disorders, and sleep treatment may aid mental health recovery. Inpatient admissions are likely a particularly challenging time for sleep. Despite this little is known about the nature of sleep problems, and how sleep treatments could be optimised for this setting. This mixed-methods study set out to better understand sleep disturbances in adolescent inpatients. Study 1 examined the prevalence of Sleep Condition Indicator-assessed insomnia at admission and associations with psychiatric symptoms and admission length in 100 inpatients (aged 11-17 years) on one unit in Oxford. Data were gathered from admission routine measures and medical records. Associations were analysed using linear regressions. Half of the inpatients (n = 50) screened positive for insomnia at admission. Moderate-large significant associations were observed between more severe insomnia and more severe depression (β = -0.56), anxiety (β = -0.51), self-harm (β = -0.49), psychotic experiences (β = -0.32), and conduct problems (β = -0.30), but not admission length. Study 2 gained 12 clinicians' perspectives on sleep problems on the unit via a focus group and semi-structured interviews, analysed using thematic analysis. Ward staff observed insomnia and excessive daytime sleepiness in adolescent inpatients and a reciprocal relationship with mental health symptoms. Ward processes were barriers (e.g., night-time observations) and facilitators (e.g., regular routines) of sleep. Cognitive behavioural therapy for insomnia was not routinely offered but viewed as potentially helpful. Insomnia may be a common problem for adolescent inpatients, associated with greater psychopathology, but not admission length. The possible benefits of psychological sleep interventions for adolescents admitted to psychiatric units now require testing.

Low risk of some common cancers in women with anorexia nervosa: Evidence from a national record-linkage study

BACKGROUND

Some studies report that women with anorexia nervosa (AN) have lower risk than others of breast cancer, but increased risk of cancers of other sites. No work has been done to quantify the risk in the English population.

METHODS

Retrospective cohort study using a national linked dataset of Hospital Episode Statistics for 1999-2021. We selected individuals with a hospital admission for AN, and compared their relative risk (RR) of developing site-specific cancers, with that in a reference cohort.

RESULTS

We identified 75 cancers in 15,029 women hospitalised with AN. There was a low RR of all cancers combined at 0.75 (95%CI 0.59-0.94), and, notably, low RR for breast cancer 0.43 (0.20-0.81), cancers of secondary and ill-defined sites 0.52 (0.26-0.93). The RR for parotid gland cancer was 4.4 (1.4-10.6) within a year of first recorded diagnosis of AN. In men, we found 12 cancers in 1413 individuals hospitalised with AN, but no increased risks beyond the first year of diagnosis of AN.

CONCLUSIONS

This is the first report on the association between AN and cancers in the all-England population. The study showed low rates of breast cancer, and of all cancers combined, in women hospitalised with AN. It is possible that some of the metabolic or hormonal changes observed in AN could work as a protective factor for breast cancer. More experimental work is needed to identify and explain these factors. The new finding on the higher risk of salivary gland tumours could inform clinicians caring for patients with AN.

Greater male than female variability in regional brain structure across the lifespan

For many traits, males show greater variability than females, with possible implications for understanding sex differences in health and disease. Here, the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) Consortium presents the largest-ever mega-analysis of sex differences in variability of brain structure, based on international data spanning nine decades of life. Subcortical volumes, cortical surface area and cortical thickness were assessed in MRI data of 16,683 healthy individuals 1-90 years old (47% females). We observed significant patterns of greater male than female between-subject variance for all subcortical volumetric measures, all cortical surface area measures, and 60% of cortical thickness measures. This pattern was stable across the lifespan for 50% of the subcortical structures, 70% of the regional area measures, and nearly all regions for thickness. Our findings that these sex differences are present in childhood implicate early life genetic or gene-environment interaction mechanisms. The findings highlight the importance of individual differences within the sexes, that may underpin sex-specific vulnerability to disorders.

Intracranial and subcortical volumes in adolescents with early-onset psychosis: A multisite mega-analysis from the ENIGMA consortium

Early-onset psychosis disorders are serious mental disorders arising before the age of 18 years. Here, we investigate the largest neuroimaging dataset, to date, of patients with early-onset psychosis and healthy controls for differences in intracranial and subcortical brain volumes. The sample included 263 patients with early-onset psychosis (mean age: 16.4 ± 1.4 years, mean illness duration: 1.5 ± 1.4 years, 39.2% female) and 359 healthy controls (mean age: 15.9 ± 1.7 years, 45.4% female) with magnetic resonance imaging data, pooled from 11 clinical cohorts. Patients were diagnosed with early-onset schizophrenia (n = 183), affective psychosis (n = 39), or other psychotic disorders (n = 41). We used linear mixed-effects models to investigate differences in intracranial and subcortical volumes across the patient sample, diagnostic subgroup and antipsychotic medication, relative to controls. We observed significantly lower intracranial (Cohen's d = -0.39) and hippocampal (d = -0.25) volumes, and higher caudate (d = 0.25) and pallidum (d = 0.24) volumes in patients relative to controls. Intracranial volume was lower in both early-onset schizophrenia (d = -0.34) and affective psychosis (d = -0.42), and early-onset schizophrenia showed lower hippocampal (d = -0.24) and higher pallidum (d = 0.29) volumes. Patients who were currently treated with antipsychotic medication (n = 193) had significantly lower intracranial volume (d = -0.42). The findings demonstrate a similar pattern of brain alterations in early-onset psychosis as previously reported in adult psychosis, but with notably low intracranial volume. The low intracranial volume suggests disrupted neurodevelopment in adolescent early-onset psychosis.

Virtual Histology of Cortical Thickness and Shared Neurobiology in 6 Psychiatric Disorders

IMPORTANCE

Large-scale neuroimaging studies have revealed group differences in cortical thickness across many psychiatric disorders. The underlying neurobiology behind these differences is not well understood.

OBJECTIVE

To determine neurobiologic correlates of group differences in cortical thickness between cases and controls in 6 disorders: attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), major depressive disorder (MDD), obsessive-compulsive disorder (OCD), and schizophrenia.

DESIGN, SETTING, AND PARTICIPANTS

Profiles of group differences in cortical thickness between cases and controls were generated using T1-weighted magnetic resonance images. Similarity between interregional profiles of cell-specific gene expression and those in the group differences in cortical thickness were investigated in each disorder. Next, principal component analysis was used to reveal a shared profile of group difference in thickness across the disorders. Analysis for gene coexpression, clustering, and enrichment for genes associated with these disorders were conducted. Data analysis was conducted between June and December 2019. The analysis included 145 cohorts across 6 psychiatric disorders drawn from the ENIGMA consortium. The numbers of cases and controls in each of the 6 disorders were as follows: ADHD: 1814 and 1602; ASD: 1748 and 1770; BD: 1547 and 3405; MDD: 2658 and 3572; OCD: 2266 and 2007; and schizophrenia: 2688 and 3244.

MAIN OUTCOMES AND MEASURES

Interregional profiles of group difference in cortical thickness between cases and controls.

RESULTS

A total of 12 721 cases and 15 600 controls, ranging from ages 2 to 89 years, were included in this study. Interregional profiles of group differences in cortical thickness for each of the 6 psychiatric disorders were associated with profiles of gene expression specific to pyramidal (CA1) cells, astrocytes (except for BD), and microglia (except for OCD); collectively, gene-expression profiles of the 3 cell types explain between 25% and 54% of variance in interregional profiles of group differences in cortical thickness. Principal component analysis revealed a shared profile of difference in cortical thickness across the 6 disorders (48% variance explained); interregional profile of this principal component 1 was associated with that of the pyramidal-cell gene expression (explaining 56% of interregional variation). Coexpression analyses of these genes revealed 2 clusters: (1) a prenatal cluster enriched with genes involved in neurodevelopmental (axon guidance) processes and (2) a postnatal cluster enriched with genes involved in synaptic activity and plasticity-related processes. These clusters were enriched with genes associated with all 6 psychiatric disorders.

CONCLUSIONS AND RELEVANCE

In this study, shared neurobiologic processes were associated with differences in cortical thickness across multiple psychiatric disorders. These processes implicate a common role of prenatal development and postnatal functioning of the cerebral cortex in these disorders.

Cognitive behavioural therapy for anxiety disorders in children and adolescents

BACKGROUND

Previous Cochrane Reviews have shown that cognitive behavioural therapy (CBT) is effective in treating childhood anxiety disorders. However, questions remain regarding the following: up-to-date evidence of the relative efficacy and acceptability of CBT compared to waiting lists/no treatment, treatment as usual, attention controls, and alternative treatments; benefits across a range of outcomes; longer-term effects; outcomes for different delivery formats; and amongst children with autism spectrum disorders (ASD) and children with intellectual impairments.

OBJECTIVES

To examine the effect of CBT for childhood anxiety disorders, in comparison with waitlist/no treatment, treatment as usual (TAU), attention control, alternative treatment, and medication.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Controlled Trials Register (all years to 2016), the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO (each to October 2019), international trial registries, and conducted grey literature searches.

SELECTION CRITERIA

We included randomised controlled trials of CBT that involved direct contact with the child, parent, or both, and included non-CBT comparators (waitlist/no treatment, treatment as usual, attention control, alternative treatment, medication). Participants were younger than age 19, and met diagnostic criteria for an anxiety disorder diagnosis. Primary outcomes were remission of primary anxiety diagnosis post-treatment, and acceptability (number of participants lost to post-treatment assessment), and secondary outcomes included remission of all anxiety diagnoses, reduction in anxiety symptoms, reduction in depressive symptoms, improvement in global functioning, adverse effects, and longer-term effects.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as recommended by Cochrane. We used GRADE to assess the quality of the evidence.

MAIN RESULTS

We included 87 studies and 5964 participants in quantitative analyses. Compared with waitlist/no treatment, CBT probably increases post-treatment remission of primary anxiety diagnoses (CBT: 49.4%, waitlist/no treatment: 17.8%; OR 5.45, 95% confidence interval (CI) 3.90 to 7.60; n = 2697, 39 studies, moderate quality); NNTB 3 (95% CI 2.25 to 3.57) and all anxiety diagnoses (OR 4.43, 95% CI 2.89 to 6.78; n = 2075, 28 studies, moderate quality). Low-quality evidence did not show a difference between CBT and TAU in post-treatment primary anxiety disorder remission (OR 3.19, 95% CI 0.90 to 11.29; n = 487, 8 studies), but did suggest CBT may increase remission from all anxiety disorders compared to TAU (OR 2.74, 95% CI 1.16 to 6.46; n = 203, 5 studies). Compared with attention control, CBT may increase post-treatment remission of primary anxiety disorders (OR 2.28, 95% CI 1.33 to 3.89; n = 822, 10 studies, low quality) and all anxiety disorders (OR 2.75, 95% CI 1.22 to 6.17; n = 378, 5 studies, low quality). There was insufficient available data to compare CBT to alternative treatments on post-treatment remission of primary anxiety disorders, and low-quality evidence showed there may be little to no difference between these groups on post-treatment remission of all anxiety disorders (OR 0.89, 95% CI 0.35 to 2.23; n = 401, 4 studies) Low-quality evidence did not show a difference for acceptability between CBT and waitlist/no treatment (OR 1.09, 95% CI 0.85 to 1.41; n=3158, 45 studies), treatment as usual (OR 1.37, 95% CI 0.73 to 2.56; n = 441, 8 studies), attention control (OR 1.00, 95% CI 0.68 to 1.49; n = 797, 12 studies) and alternative treatment (OR 1.58, 95% CI 0.61 to 4.13; n=515, 7 studies). No adverse effects were reported across all studies; however, in the small number of studies where any reference was made to adverse effects, it was not clear that these were systematically monitored. Results from the anxiety symptom outcomes, broader outcomes, longer-term outcomes and subgroup analyses are provided in the text. We did not find evidence of consistent differences in outcomes according to delivery formats (e.g. individual versus group; amount of therapist contact time) or amongst samples with and without ASD, and no studies included samples of children with intellectual impairments.

AUTHORS' CONCLUSIONS

CBT is probably more effective in the short-term than waiting lists/no treatment, and may be more effective than attention control. We found little to no evidence across outcomes that CBT is superior to usual care or alternative treatments, but our confidence in these findings are limited due to concerns about the amount and quality of available evidence, and we still know little about how best to efficiently improve outcomes.

Disrupted brain structural connectivity in Pediatric Bipolar Disorder with psychosis

Bipolar disorder (BD) has been linked to disrupted structural and functional connectivity between prefrontal networks and limbic brain regions. Studies of patients with pediatric bipolar disorder (PBD) can help elucidate the developmental origins of altered structural connectivity underlying BD and provide novel insights into the aetiology of BD. Here we compare the network properties of whole-brain structural connectomes of euthymic PBD patients with psychosis, a variant of PBD, and matched healthy controls. Our results show widespread changes in the structural connectivity of PBD patients with psychosis in both cortical and subcortical networks, notably affecting the orbitofrontal cortex, frontal gyrus, amygdala, hippocampus and basal ganglia. Graph theoretical analysis revealed that PBD connectomes have fewer hubs, weaker rich club organization, different modular fingerprint and inter-modular communication, compared to healthy participants. The relationship between network features and neurocognitive and psychotic scores was also assessed, revealing trends of association between patients’ IQ and affective psychotic symptoms with the local efficiency of the orbitofrontal cortex. Our findings reveal that PBD with psychosis is associated with significant widespread changes in structural network topology, thus strengthening the hypothesis of a reduced capacity for integrative processing of information across brain regions. Localised network changes involve core regions for emotional processing and regulation, as well as memory and executive function, some of which show trends of association with neurocognitive faculties and symptoms. Together, our findings provide the first comprehensive characterisation of the alterations in local and global structural brain connectivity and network topology, which may contribute to the deficits in cognition and emotion processing and regulation found in PBD.

Determinants of inter-practice variation in ADHD diagnosis and stimulant prescribing: cross-sectional database study of a national surveillance network

Early recognition, identification and treatment of children with attention deficit hyperactivity disorder (ADHD) can reduce detrimental outcomes and redirect their developmental trajectory. We aimed to describe variations in age of ADHD diagnosis and stimulant prescribing among general practitioner practices in a nationwide network and identify child, parental, household and general practice factors that might account for these variations. Cross-sectional study of children aged under 19 years registered within a general practice in the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) network in 2016, RCGP RSC has a household key allowing parent and child details to be linked. Data from 158 general practices and 353 774 children under 19 were included. The mean age of first ADHD diagnosis was 10.5 years (95% CI 10.1 to 10.9, median 10, IQR 9.0-11.9) and the mean percentage of children with ADHD prescribed stimulant medications among RCGP RSC practices was 41.2% (95% CI 38.7 to 43.6). There was wide inter-practice variation in the prevalence of diagnosis of ADHD, the age of diagnosis and stimulant prescribing. ADHD diagnosis is more likely to be made later in households with a greater number of children and with a larger age difference between adults and children. Stimulant prescribing for children with ADHD was higher in less deprived practices. Older parents and families with more children fail to recognise ADHD and may need more support. Practices in areas of higher socio-economic status are associated with greater prescribing of stimulants for children with ADHD.

Different Types and Acceptability of Psychotherapies for Acute Anxiety Disorders in Children and Adolescents: A Network Meta-analysis

IMPORTANCE

Anxiety disorders are common in children and adolescents, and uncertainty remains regarding the optimal strategy of psychotherapies in this population.

OBJECTIVE

To compare and rank the different types of psychotherapies and the different ways of delivering psychological treatments for anxiety disorders in children and adolescents.

DATA SOURCES

PubMed, Cochrane Central Register of Controlled Trials, EMBASE, PsycINFO, Web of Science, CINAHL (Cumulative Index to Nursing and Allied Health Literature), ProQuest Dissertations, LILACS (Literatura Latino Americana em Ciências da Saúde), international trial registers, and US Food and Drug Administration reports were searched from inception to November 30, 2017.

STUDY SELECTION

Randomized clinical trials that compared any structured psychotherapy with another psychotherapy or a control condition for anxiety disorders in children and adolescents were selected.

DATA EXTRACTION AND SYNTHESIS

Four researchers independently performed data extraction and quality assessment. Pairwise meta-analyses and Bayesian network meta-analysis within the random-effects model were used to synthesize data.

MAIN OUTCOMES AND MEASURES

Efficacy (change in anxiety symptoms) posttreatment and at follow-up, acceptability (all-cause discontinuation), and quality of life and functional improvement were measured. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation framework.

RESULTS

A total of 101 unique trials including 6625 unique participants compared 11 different psychotherapies with 4 specific control conditions. The certainty of evidence was rated as low or very low for most comparisons. For efficacy, most psychotherapies were significantly more effective than the wait list condition posttreatment (standardized mean difference [SMD], -1.43 to -0.61) and at the longest follow-up (SMD, -1.84 to -1.64). However, only group cognitive behavioral therapy (CBT) was significantly more effective than the other psychotherapies and all control conditions posttreatment. For acceptability, bibliotherapy CBT had significantly more all-cause discontinuations than some psychotherapies and control conditions (range of odds ratios, 2.48-9.32). In terms of quality of life and functional improvement, CBT (delivered in different ways) was significantly beneficial compared with psychological placebo and the wait list condition (SMDs, 0.73 to 1.99).

CONCLUSIONS AND RELEVANCE

Group CBT would be the more appropriate choice of psychotherapy for anxiety disorders in children and adolescents, based on these findings. Other types of psychotherapies and different ways of delivering psychological treatment can be alternative options. Further research is needed to explore specific anxiety disorders, disorder-specific psychotherapy, and moderators of treatment effect.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42015016283.

Prescribing antipsychotics for children and adolescents

The prescription of antipsychotic medication in children and adolescents (<18 years of age) has increased immensely for a wide range of disorders including psychoses, bipolar disorder, conduct disorder, pervasive developmental disorder and obsessive–compulsive disorder. This has led to some concerns particularly as the evidence base in some areas is not strong, and antipsychotic medication – both first generation (FGA) and second generation (SGA) – is associated with considerable side-effects. Evidence from an increasing number of randomised controlled trials (RCTs) points to therapeutic efficacy with moderate to large effect sizes. However, some RCTs have a small number of participants, are of short duration, and many are industry funded. The use of antipsychotics alongside psychosocial interventions can be recommended in certain disorders, provided there is continued, careful monitoring. It is important to note, however, that for many conditions the use of antipsychotics is not licensed in the UK.

Notch1 endocytosis is induced by ligand and is required for signal transduction

The Notch signalling pathway is widely utilised during embryogenesis in situations where cell-cell interactions are important for cell fate specification and differentiation. DSL ligand endocytosis into the ligand-expressing cell is an important aspect of Notch signalling because it is thought to supply the force needed to separate the Notch heterodimer to initiate signal transduction. A functional role for receptor endocytosis during Notch signal transduction is more controversial. Here we have used live-cell imaging to examine trafficking of the Notch1 receptor in response to ligand binding. Contact with cells expressing ligands induced internalisation and intracellular trafficking of Notch1. Notch1 endocytosis was accompanied by transendocytosis of ligand into the Notch1-expressing signal-receiving cell. Ligand caused Notch1 endocytosis into SARA-positive endosomes in a manner dependent on clathrin and dynamin function. Moreover, inhibition of endocytosis in the receptor-expressing cell impaired ligand-induced Notch1 signalling. Our findings resolve conflicting observations from mammalian and Drosophila studies by demonstrating that ligand-dependent activation of Notch1 signalling requires receptor endocytosis. Endocytosis of Notch1 may provide a force on the ligand:receptor complex that is important for potent signal transduction.

Comparative efficacy and acceptability of psychotherapies for acute anxiety disorders in children and adolescents: study protocol for a network meta-analysis

INTRODUCTION

Anxiety disorders are associated with significant public health burden in young individuals. Cognitive-behavioural therapy (CBT) is the most commonly used psychotherapy for anxiety disorders in children and adolescents, but previous reviews were hindered by a limited number of trials with direct comparisons between different psychotherapies and their deliveries. Consequently, the main aim of this research was to investigate the comparative efficacy and acceptability of various types and deliveries of psychotherapies for anxiety disorders in children and adolescents.

METHODS AND ANALYSIS

We will systematically search PubMed, EMBASE, Cochrane, Web of Science, PsycINFO, CINAHL, ProQuest Dissertations and LiLACS for randomised controlled trials, regardless of whether participants received blinding or not, published from 1 January 1966 to 30 January 2015 (updated to 1 July 2015), that compared any psychotherapy with either a control condition or an active comparator with different types and/or different delivery formats for the acute treatment of anxiety disorders in children and adolescents. Data extraction, risk of bias and quality assessments will be independently extracted by two reviewers. The primary outcome for efficacy will be mean overall change scores in anxiety symptoms (self-rated or assessor-rated) from baseline to post-treatment between two groups. The acceptability of treatment will be measured as the proportion of patients who discontinued treatment during the acute phase of treatment. We will assess efficacy, based on the standardised mean difference (SMD), and acceptability, based on the OR, using a random-effects network meta-analysis within a Bayesian framework. Subgroup and sensitivity analyses will be conducted to assess the robustness of the findings.

ETHICS AND DISSEMINATION

No ethical issues are foreseen. The results will be published in a peer-reviewed journal and will be disseminated electronically and in print. The meta-analysis may be updated to inform and guide management of anxiety in children and adolescents.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42015016283.

Fear responses to safety cues in anxious adolescents: Preliminary evidence for atypical age-associated trajectories of functional neural circuits

Adolescent anxiety is common and impairing and often persists into adulthood. There is growing evidence that adult anxiety is characterized by abnormal fear responses to threat and safety cues, along with perturbations in fear-related neural circuits. Although some of this work has been extended to adolescents, with promising results, it is not yet clear whether changes in these circuits across developmental age varies between anxious and non-anxious adolescents. Here we used fMRI to examine how age modulates neural responses as adolescents are exposed to threat and safety cues. Participants were 15 anxious and 11 non-anxious adolescents (age 12-17) who completed a fear conditioning paradigm. The paradigm incorporated a threat cue comprising a neutral face which was paired with a fearful, screaming face, a safety cue comprising a different neutral face, and a control stimulus. Across the whole sample, neural activation to the threat cue (relative to the control cue) correlated positively with age in a number of regions, including the dorsal anterior cingulate and bilateral dorsolateral prefrontal cortex (PFC). However, neural activation to the safety cue (relative to the control cue) was modulated differently by age in the two groups: a more positive association between activation and age was observed in the control group compared to the anxious group in various regions including medial and dorsolateral PFC, anterior insula, and amygdala. These findings suggest that maturation of the neural substrates of fear responses to safety cues may be perturbed in anxious adolescents, potentially contributing to the emergence and maintenance of anxiety disorders in adulthood.

Cognitive behavioural therapy for anxiety disorders in children and adolescents

BACKGROUND

A previous Cochrane review (James 2005) showed that cognitive behavioural therapy (CBT) was effective in treating childhood anxiety disorders; however, questions remain regarding (1) the relative efficacy of CBT versus non-CBT active treatments; (2) the relative efficacy of CBT versus medication and the combination of CBT and medication versus placebo; and (3) the long-term effects of CBT. 

OBJECTIVES

To examine (1) whether CBT is an effective treatment for childhood and adolescent anxiety disorders in comparison with (a) wait-list controls; (b) active non-CBT treatments (i.e. psychological placebo, bibliotherapy and treatment as usual (TAU)); and (c) medication and the combination of medication and CBT versus placebo; and (2) the long-term effects of CBT.

SEARCH METHODS

Searches for this review included the Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Depression, Anxiety and Neurosis Group Register, which consists of relevant randomised controlled trials from the bibliographic databases－The Cochrane Library (1970 to July 2012), EMBASE, (1970 to July 2012) MEDLINE (1970 to July 2012) and PsycINFO (1970 to July 2012).

SELECTION CRITERIA

All randomised controlled trials (RCTs) of CBT versus waiting list, active control conditions, TAU or medication were reviewed. All participants must have met the criteria of the Diagnostic and Statistical Manual (DSM) or the International Classification of Diseases (ICD) for an anxiety diagnosis, excluding simple phobia, obsessive-compulsive disorder, post-traumatic stress disorder and elective mutism.

DATA COLLECTION AND ANALYSIS

The methodological quality of included trials was assessed by three reviewers independently. For the dichotomous outcome of remission of anxiety diagnosis, the odds ratio (OR) with 95% confidence interval (CI) based on the random-effects model, with pooling of data via the inverse variance method of weighting, was used. Significance was set at P < 0.05. Continuous data on each child's anxiety symptoms were pooled using the standardised mean difference (SMD).

MAIN RESULTS

Forty-one studies consisting of 1806 participants were included in the analyses. The studies involved children and adolescents with anxiety of mild to moderate severity in university and community clinics and school settings. For the primary outcome of remission of any anxiety diagnosis for CBT versus waiting list controls, intention-to-treat (ITT) analyses with 26 studies and 1350 participants showed an OR of 7.85 (95% CI 5.31 to 11.60, Z = 10.26, P < 0.0001), but with evidence of moderate heterogeneity (P = 0.04, I² = 33%). The number needed to treat (NNT) was 6.0 (95% CI 7.5 to 4.6). No difference in outcome was noted between individual, group and family/parental formats. ITT analyses revealed that CBT was no more effective than non-CBT active control treatments (six studies, 426 participants) or TAU in reducing anxiety diagnoses (two studies, 88 participants). The few controlled follow-up studies (n = 4) indicate that treatment gains in the remission of anxiety diagnosis are not statistically significant.

AUTHORS' CONCLUSIONS

Cognitive behavioural therapy is an effective treatment for childhood and adolescent anxiety disorders; however, the evidence suggesting that CBT is more effective than active controls or TAU or medication at follow-up, is limited and inconclusive.

Cognitive reappraisal of peer rejection in depressed versus non-depressed adolescents: functional connectivity differences

BACKGROUND

Depression is the most common psychiatric disorder in adolescence, and is characterised by an inability to down-regulate negative emotional responses to stress. Adult studies suggest this may be associated with reduced functional connectivity between prefrontal and subcortical regions, yet the neurological mechanisms in adolescence remain unclear.

METHODS

We developed a novel, age-appropriate, reappraisal paradigm to investigate functional connectivity during reappraisal of a real-life source of stress in 15 depressed and 15 non-depressed adolescents. During fMRI, participants i) attended to, and ii) implemented reappraisal techniques (learnt prior to fMRI) in response to, rejection.

RESULTS

Reappraisal reduced negative mood and belief in negative thoughts in both groups alike, however during reappraisal (versus attend) trials, depressed adolescents showed greater connectivity between the right frontal pole and numerous subcortical and cortical regions than non-depressed adolescents.

CONCLUSIONS

These findings tentatively suggest that, when instructed, depressed adolescents do have the ability to engage neural networks involved in emotion regulation, possibly because adolescence reflects a period of heightened plasticity. These data support the value of cognitive reappraisal as a treatment tool, identify neural markers that could be used to optimise current therapies, and lay the foundations for developing novel neuroscientific techniques for the treatment of adolescent depression.

Notch4 reveals a novel mechanism regulating Notch signal transduction

Notch4 is a divergent member of the Notch family of receptors that is primarily expressed in the vasculature. Its expression implies an important role for Notch4 in the vasculature; however, mice homozygous for the Notch4(d1) knockout allele are viable. Since little is known about the role of Notch4 in the vasculature and how it functions, we further investigated Notch4 in mice and in cultured cells. We found that the Notch4(d1) allele is not null as it expresses a truncated transcript encoding most of the NOTCH4 extracellular domain. In cultured cells, NOTCH4 did not signal in response to ligand. Moreover, NOTCH4 inhibited signalling from the NOTCH1 receptor. This is the first report of cis-inhibition of signalling by another Notch receptor. The NOTCH4 extracellular domain also inhibits NOTCH1 signalling when expressed in cis, raising the possibility that reported Notch4 phenotypes may not be due to loss of NOTCH4 function. To better address the role of NOTCH4 in vivo, we generated a Notch4 null mouse in which the entire coding region was deleted. Notch4 null mice exhibited slightly delayed vessel growth in the retina, consistent with our novel finding that NOTCH4 protein is expressed in the newly formed vasculature. These findings indicate a role of NOTCH4 in fine-tuning the forming vascular plexus.

Laterality interacts with sex across the schizophrenia/bipolarity continuum: an interpretation of meta-analyses of structural MRI

Review of the first comprehensive meta-analysis of VBM (voxel-based morphometry) studies in schizophrenia indicates asymmetrical reductions of anterior cingulate gyrus to the right, and medial temporal lobe (including the uncus) and para-hippocampal gyrus to the left. In subsequent meta-analyses of schizophrenia and bipolar disorder change in these limbic structures is systematically related to change in the insula. Deficits in insula (and para-hippocampal gyrus) to the left, and dorsal anterior cingulate gyrus to the right are greater in schizophrenic psychoses whereas deficits in anterior cingulate to the left and insula to the right are greater in bipolar illness. Thus (1) brain structures implicated in schizophrenia include those implicated in bipolar disorder, (2) the variation that separates the prototypical psychoses may be a subset of that relating to the structural asymmetry (the "torque") characteristic of the human brain, and (3) the meta-analysis of Bora et al. (2012) indicates that laterality of involvement of the insula and cingulate gyrus across the spectrum of bipolar and schizophrenic psychoses is critically dependent upon the sex ratio. Thus structural change underlying the continuum of psychosis relates to the interaction of laterality and sex.

Structural connectivity in schizophrenia and its impact on the dynamics of spontaneous functional networks

The neuropathology of schizophrenia remains unclear. Some insight has come from modern neuroimaging techniques, which offer an unparalleled opportunity to explore in vivo the structure and function of the brain. Using functional magnetic resonance imaging, it has been found that the large-scale resting-state functional connectivity (rsFC) in schizophrenia--measured as the temporal correlations of the blood-oxygen-level-dependent (BOLD) signal--exhibit altered network topology, with lower small-world index. The origin of these rsFC alterations and link with the underlying structural connectivity remain unclear. In this work, we used a computational model of spontaneous large-scale brain activity to explore the role of the structural connectivity in the large-scale dynamics of the brain in health and schizophrenia. The structural connectomes from 15 adolescent patients with early-onset schizophrenia and 15 age- and gender-matched controls were built from diffusion tensor imaging data to detect the white matter tracts between 90 brain areas. Brain areas, simulated using a reduced dynamic mean-field model, receive excitatory input from other areas in proportion to the number of fibre tracts between them. The simulated mean field activity was transformed into BOLD signal, and the properties of the simulated functional networks were analyzed. Our results suggest that the functional alterations observed in schizophrenia are not directly linked to alterations in the structural topology. Instead, subtly randomized and less small-world functional networks appear when the brain operates with lower global coupling, which shifts the dynamics from the optimal healthy regime.

Pupillary response to sparse multifocal stimuli in multiple sclerosis patients

OBJECTIVES

The objective of this paper is to investigate the pattern of abnormalities and establish the diagnostic power of multifocal objective pupil perimetry (mfPOP) in multiple sclerosis (MS).

METHODS

A prospective study enrolling 35 normal (47.9 ± 16.8 years, 22 females) and 85 MS subjects (49.8 ± 11.3 years, 62 females; 72 relapsing-remitting (RR), and 13 primary or secondary progressives (PorS)). EDSS scores for the RR and PorS groups were 3.53 ± 1.04 (mean ± SD), and 5.9 ± 1.43, respectively. mfPOP responses were obtained from 44 regions/visual field. Each region was analysed according to response time-to-peak and standardised amplitude (AmpStd). Predictive power was measured by percentage area under the receiver operator curve (%AUC).

RESULTS

mfPOP responses showed a significant reduction of 0.69 ± 0.04 dB (mean ± SE) in AmpStd and significantly delayed time-to-peak of 25.95 ± 0.89 ms (mean ± SE) in MS subjects compared to control subjects (p<0.001). %AUC was greater for time-to-peak than AmpStd both for RR and PorS patients. Diagnostic power followed the EDSS scores but not a history of optic neuritis.

CONCLUSIONS

mfPOP is well tolerated and potentially has a role in the diagnosis and assessment of patients with MS.

Anxious and non-anxious adolescents' experiences of non-clinical magnetic resonance imaging research

Magnetic resonance imaging (MRI) has become a ubiquitous research tool for developmental neuroscientists interested in brain structure and function in children and adolescents. However, ethical concerns are sometimes raised about using MRI with children and adolescents, especially when participants have anxiety. We asked 17 clinically/sub-clinically anxious and 19 non-anxious adolescents about their experiences of taking part in MRI for research purposes. Although the anxious group reported experiencing more anxiety during the scan, these differences had attenuated by the time participants got home. We found no evidence that anxious adolescents would be less likely to choose to have another scan or would feel more nervous during another scan. There was some evidence that more trait anxious adolescents found the MRI study enjoyable. These findings should give ethics committees, clinicians, and parents confidence that so long as researchers exercise appropriate care, MRI research is acceptable to adolescents, including those with clinical anxiety.

Cognitive behavioural therapy for anxiety disorders in children and adolescents

BACKGROUND

A previous Cochrane review (James 2005) showed that cognitive behavioural therapy (CBT) was effective in treating childhood anxiety disorders; however, questions remain regarding (1) the relative efficacy of CBT versus non-CBT active treatments; (2) the relative efficacy of CBT versus medication and the combination of CBT and medication versus placebo; and (3) the long-term effects of CBT. 

OBJECTIVES

To examine (1) whether CBT is an effective treatment for childhood and adolescent anxiety disorders in comparison with (a) wait-list controls; (b) active non-CBT treatments (i.e. psychological placebo, bibliotherapy and treatment as usual (TAU)); and (c) medication and the combination of medication and CBT versus placebo; and (2) the long-term effects of CBT.

SEARCH METHODS

Searches for this review included the Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Depression, Anxiety and Neurosis Group Register, which consists of relevant randomised controlled trials from the bibliographic databases－The Cochrane Library (1970 to July 2012), EMBASE, (1970 to July 2012) MEDLINE (1970 to July 2012) and PsycINFO (1970 to July 2012).

SELECTION CRITERIA

All randomised controlled trials (RCTs) of CBT versus waiting list, active control conditions, TAU or medication were reviewed. All participants must have met the criteria of the Diagnostic and Statistical Manual (DSM) or the International Classification of Diseases (ICD) for an anxiety diagnosis, excluding simple phobia, obsessive-compulsive disorder, post-traumatic stress disorder and elective mutism.

DATA COLLECTION AND ANALYSIS

The methodological quality of included trials was assessed by three reviewers independently. For the dichotomous outcome of remission of anxiety diagnosis, the odds ratio (OR) with 95% confidence interval (CI) based on the random-effects model, with pooling of data via the inverse variance method of weighting, was used. Significance was set at P < 0.05. Continuous data on each child's anxiety symptoms were pooled using the standardised mean difference (SMD).

MAIN RESULTS

Forty-one studies consisting of 1806 participants were included in the analyses. The studies involved children and adolescents with anxiety of mild to moderate severity in university and community clinics and school settings. For the primary outcome of remission of any anxiety diagnosis for CBT versus waiting list controls, intention-to-treat (ITT) analyses with 26 studies and 1350 participants showed an OR of 0.13 (95% CI 0.09 to 0.19, Z = 10.26, P < 0.0001), but with evidence of moderate heterogeneity (P = 0.04, I² = 33%). The number needed to treat (NNT) was 6.0 (95% CI 7.5 to 4.6). No difference in outcome was noted between individual, group and family/parental formats. ITT analyses revealed that CBT was no more effective than non-CBT active control treatments (six studies, 426 participants) or TAU in reducing anxiety diagnoses (two studies, 88 participants). The few controlled follow-up studies (n = 4) indicate that treatment gains in the remission of anxiety diagnosis are not statistically significant.

AUTHORS' CONCLUSIONS

Cognitive behavioural therapy is an effective treatment for childhood and adolescent anxiety disorders; however, the evidence suggesting that CBT is more effective than active controls or TAU or medication at follow-up, is limited and inconclusive.

Gyrification of Broca's region is anomalously lateralized at onset of schizophrenia in adolescence and regresses at 2 year follow-up

Gyrification of the human cerebral cortex starts in the foetus and progresses in early infancy; the pattern of folding in later life provides a lead to early developmental aberration. By studying gyrification at illness onset in adolescence we hoped to clarify the pathophysiology of schizophrenia. Here we find 1) an area of hypergyria includes Broca's area and extends into the Sylvian fissure to encroach on the anterior insula in the left hemisphere, and 2) an area of hypogyria in the superior temporal lobe approximates to Wernicke's area but is located in the right hemisphere and encroaches on the posterior insula. In Broca's/anterior insula area, right lateralization was present in healthy controls but patients were left lateralized: at two year follow-up gyrification had decreased in patients while it increased in controls, and the reduction predicted impaired category fluency. Progressive change was unaccompanied by cortical thinning (investigated only in the brain regions showing baseline changes in gyrification) indicating that the disease process affecting these brain regions (insula, inferior frontal and superior temporal) is not primarily degenerative. A deviation in the lateralized development of peri-Sylvian areas for language production and comprehension appears critical to the pathophysiology of schizophrenia and may point to its species-specific origin.

Sexually dimorphic white matter geometry abnormalities in adolescent onset schizophrenia

The normal human brain is characterized by a pattern of gross anatomical asymmetry. This pattern, known as the "torque", is associated with a sexual dimorphism: The male brain tends to be more asymmetric than that of the female. This fact, along with well-known sex differences in brain development (faster in females) and onset of psychosis (earlier with worse outcome in males), has led to the theory that schizophrenia is a disorder in which sex-dependent abnormalities in the development of brain torque, the correlate of the capacity for language, cause alterations in interhemispheric connectivity, which are causally related to psychosis (Crow TJ, Paez P, Chance SE. 2007. Callosal misconnectivity and the sex difference in psychosis. Int Rev Psychiatry. 19(4):449-457.). To provide evidence toward this theory, we analyze the geometry of interhemispheric white matter connections in adolescent-onset schizophrenia, with a particular focus on sex, using a recently introduced framework for white matter geometry computation in diffusion tensor imaging data (Savadjiev P, Kindlmann GL, Bouix S, Shenton ME, Westin CF. 2010. Local white geometry from diffusion tensor gradients. Neuroimage. 49(4):3175-3186.). Our results reveal a pattern of sex-dependent white matter geometry abnormalities that conform to the predictions of Crow's torque theory and correlate with the severity of patients' symptoms. To the best of our knowledge, this is the first study to associate geometrical differences in white matter connectivity with torque in schizophrenia.

White matter development in adolescence: diffusion tensor imaging and meta-analytic results

BACKGROUND

In light of the evidence for brain white matter (WM) abnormalities in schizophrenia, study of normal WM maturation in adolescence may provide critical insights relevant to the neurodevelopment of the disorder. Voxel-wise diffusion tensor imaging (DTI) studies have consistently demonstrated increases in fractional anisotropy (FA), a putative measure of WM integrity, from childhood into adolescence. However, the WM tracts that show FA increases have been variable across studies. Here, we aimed to assess which WM tracts show the most pronounced changes across adolescence.

METHODS

DTI was performed in 78 healthy subjects aged 8-21 years, and voxel-wise analysis conducted using tract-based spatial statistics (TBSS). In addition, we performed the first meta-analysis of TBSS studies on WM development in adolescence.

RESULTS

In our sample, we observed bilateral increases in FA with age, which were most significant in the left superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and anterior thalamic radiation. These findings were confirmed by the meta-analysis, and FA increase in the bilateral SLF was the most consistent finding across studies. Moreover, in our sample, FA of the bilateral SLF showed a positive association with verbal working memory performance and partially mediated increases in verbal fluency as a function of increasing age.

CONCLUSIONS

These data highlight increasing connectivity in the SLF during adolescence. In light of evidence for compromised SLF integrity in high-risk and first-episode patients, these data suggest that abnormal maturation of the SLF during adolescence may be a key target in the neurodevelopment of schizophrenia.

Photopic and scotopic multifocal pupillographic responses in age-related macular degeneration

We compared photopic and scotopic multifocal pupillographic stimuli in age-related macular degeneration (AMD). Both eyes of 18 normal and 14 AMD subjects were tested with four stimulus variants presented at photopic and 126 times lower luminances. The multifocal stimuli presented 24 test regions/eye to the central 60°. The stimulus variants had two different check sizes, and when presented either flickered (15 Hz) for 266 ms, or were steady for 133 ms. Mean differences from normal of 5 to 7 dB were observed in the central visual field for both photopic and scotopic stimuli (all p < 0.00002). The best areas under receiver operating characteristic plots for exudative AMD in the photopic and scotopic conditions were 92.9 ± 8.0 and 90.3 ± 5.7% respectively, and in less severely affected eyes 83.8 ± 9.7% and 76.9 ± 8.2%. Damage recorded at photopic levels was possibly more diffusely distributed across the visual field. Sensitivity and specificity was similar at photopic and scotopic levels.

Microdistribution and long-term retention of 239Pu (NO3)4 in the respiratory tracts of an acutely exposed plutonium worker and experimental beagle dogs

The long-term retention of inhaled soluble forms of plutonium raises concerns as to the potential health effects in persons working in nuclear energy or the nuclear weapons program. The distributions of long-term retained inhaled plutonium-nitrate [(239)Pu (NO(3))(4)] deposited in the lungs of an accidentally exposed nuclear worker (Human Case 0269) and in the lungs of experimentally exposed beagle dogs with varying initial lung depositions were determined via autoradiographs of selected histologic lung, lymph node, trachea, and nasal turbinate tissue sections. These studies showed that both the human and dogs had a nonuniform distribution of plutonium throughout the lung tissue. Fibrotic scar tissue effectively encapsulated a portion of the plutonium and prevented its clearance from the body or translocation to other tissues and diminished dose to organ parenchyma. Alpha radiation activity from deposited plutonium in Human Case 0269 was observed primarily along the subpleural regions while no alpha activity was seen in the tracheobronchial lymph nodes of this individual. However, relatively high activity levels in the tracheobronchial lymph nodes of the beagles indicated the lymphatic system was effective in clearing deposited plutonium from the lung tissues. In both the human case and beagle dogs, the appearance of retained plutonium within the respiratory tract was inconsistent with current biokinetic models of clearance for soluble forms of plutonium. Bound plutonium can have a marked effect on the dose to the lungs and subsequent radiation exposure has the potential to increase cancer risk.

Reevaluation of USTUR plutonium wound case 0262 using Bayesian methodology and new data

Skin penetration by radionuclide contaminants serves as a route of entry into the body and may pose a serious health risk to humans depending on the magnitude of intake. The United States Transuranium and Uranium Registry whole body Case 0262 was involved in a wound intake of plutonium at the Hanford Site. The registrant died about 33 years later. Results were initially reported in 2007 regarding the deposition and retention of plutonium in various tissues, including the wound site. However in 2009, an additional (previously unrecorded) sample of the wound tissue was located in the National Human Radiobiological Tissue Repository. The new sample was analyzed using inductively coupled plasma-mass spectrometry (ICP-MS), and the results were used to calibrate the measurement of emitted Pu x-rays from the original wound tissue sample made in 2007. In the present study, the analysis of Pu absorption rates from the wound and axillary lymph node from the initial study is repeated using the additional wound activity data and ICP-MS calibration. This new analysis is carried out using the Weighted Likelihood Monte Carlo Sampling (WeLMoS) method and code, which applies Bayesian inference to calculate the posterior probability distribution of intake and wound absorption parameters directly from the observed data and the assumed biokinetic model structure. The resulting central estimates of empirical wound absorption parameters and their associated uncertainties are here compared with the empirical values recommended in NCRP Report No. 156 for plutonium and with the maximum likelihood point estimates derived in the initial study from the Case 0262 data available at the time.

Maximum likelihood analysis of bioassay data from long-term follow-up of two refractory PuO2 inhalation cases

The U.S. Transuranium and Uranium Registries' tissue donors 0202 and 0407 are the two most highly exposed of the 18 registrants who were involved in the 1965 plutonium fire accident at a defense nuclear facility. Material released during the fire was well characterized as "high fired" refractory plutonium dioxide with 0.32-μm mass median diameter. The extensive bioassay data from long-term follow-up of these two cases were used to evaluate the applicability of the Human Respiratory Tract Model presented by International Commission on Radiological Protection in Publication 66 and its revision proposed by Gregoratto et al. in order to account for the observed long-term retention of insoluble material in the lungs. The maximum likelihood method was used to calculate the point estimates of intake and tissue doses and to examine the effect of different lung clearance, blood absorption, and systemic models on the goodness-of-fit and estimated dose values. With appropriate adjustments, Gregoratto et al. particle transport model coupled with the customized blood absorption parameters yielded a credible fit to the bioassay data for both cases and predicted the Case 0202 liver and skeletal activities measured postmortem. PuO2 particles produced by the plutonium fire are extremely insoluble. About 1% of this material is absorbed from the respiratory tract relatively rapidly, at a rate of about 1 to 2 d (half-time about 8 to 16 h). The remainder (99%) is absorbed extremely slowly, at a rate of about 5 × 10(-6) d (half-time about 400 y). When considering this situation, it appears that doses to other body organs are negligible in comparison to those to tissues of the respiratory tract. About 96% of the total committed weighted dose equivalent is contributed by the lungs. Doses absorbed by these workers' lungs were high: 3.2 Gy to AI and 6.5 Gy to LNTH for Case 0202 (18 y post-intake) and 3.2 Gy to AI and 55.5 Gy to LNTH for Case 0407 (43 y post-intake). This evaluation supports the Gregoratto et al. proposed revision to the ICRP 66 model when considering situations of extremely insoluble particles.

Abnormal intrinsic and extrinsic connectivity within the magnetic mismatch negativity brain network in schizophrenia: a preliminary study

Altered neuroplasticity is increasingly invoked as a mechanism underpinning dysconnectivity in schizophrenia. We used Dynamic Causal Modelling to compare connectivity during the magnetic auditory Mismatch Negativity (MMN), an index of error prediction, between schizophrenia patients and controls. Patients showed reduced intrinsic connectivity within the primary auditory cortex suggestive of impaired local neuronal adaptation and disrupted forward and backward extrinsic connectivity throughout the MMN network indicative of reduced higher order input in disambiguating activity in lower network nodes. Our study provides the first empirical description of the dysplastic changes underpinning dysconnectivity between primary sensory and higher order cortical areas in schizophrenia.

EURADOS coordinated action on research, quality assurance and training of internal dose assessments

EURADOS working group on 'Internal Dosimetry (WG7)' represents a frame to develop activities in the field of internal exposures as coordinated actions on quality assurance (QA), research and training. The main tasks to carry out are the update of the IDEAS Guidelines as a reference document for the internal dosimetry community, the implementation and QA of new ICRP biokinetic models, the assessment of uncertainties related to internal dosimetry models and their application, the development of physiology-based models for biokinetics of radionuclides, stable isotope studies, biokinetic modelling of diethylene triamine pentaacetic acid decorporation therapy and Monte-Carlo applications to in vivo assessment of intakes. The working group is entirely supported by EURADOS; links are established with institutions such as IAEA, US Transuranium and Uranium Registries (USA) and CEA (France) for joint collaboration actions.

EURADOS intercomparison on measurements and Monte Carlo modelling for the assessment of americium in a USTUR leg phantom

A collaboration of the EURADOS working group on 'Internal Dosimetry' and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here.

A Preliminary Study of an Extension of a Community Dialectic Behaviour Therapy (DBT) Programme to Adolescents in the Looked After Care System

BACKGROUND

  Adolescents in the Looked After Care (LAC) system demonstrate high rates of psychiatric disorder and self-harm; however, there is little evidence for therapies reducing self-harm in this population.

METHOD

  An open evaluation of DBT for adolescents with repeated serious self-harm in the LAC system was undertaken.

RESULTS

  An intention-to-treat (ITT) analysis showed that DBT was successful at reducing the core elements of depression, hopelessness and self-harm; however, 35% (7/20) failed to engage.

CONCLUSION

  DBT is a useful treatment option; the failure, however, of some adolescents to engage in therapy may be due to their higher initial rates of depression and hopelessness.

Paracingulate sulcus asymmetry; sex difference, correlation with semantic fluency and change over time in adolescent onset psychosis

The left paracingulate sulcus (PCS) is longer than the right and the adjacent cortex is activated by the generation of words. In adult patients with chronic schizophrenia the anatomical asymmetry is reduced. In 35 controls and 38 adolescents with schizophrenia or schizoaffective disorder (mean age = 16 years) we found that semantic verbal fluency correlated with leftward PCS asymmetry in controls but not in patients. At intake, PCS length did not differ between patients and controls, but at follow-up (13 controls, 10 patients, mean age = 18 years) PCS asymmetry (comprising both increasing left and decreasing right length) increased significantly, the increase was greater in males than in females, and there was a trend for a diagnosis * sex * side * time interaction such that in controls leftward PCS asymmetry increased, while in patients of both sexes there was convergence toward symmetry. Thus sulcal anatomy develops differentially in the two sexes during adolescence, and the pattern of asymmetric sex-dependent change over time may distinguish patients with psychosis from controls. Greater change in asymmetry during adolescence may explain earlier age of onset in males and greater deficits in verbal fluency.

Attenuation of perceptual asymmetries in patients with early‐onset schizophrenia: Evidence in favour of reduced hemispheric differentiation in schizophrenia?

Lateral biases in visual perception have been demonstrated in normal individuals and in patients with unilateral brain lesions. It has been suggested that the absence of structural and functional asymmetries in schizophrenia could be due to a failure in lateralisation that may be most pronounced in those patients whose illness onset is at an early age. Here we examined lateral biases in patients with schizophrenia of an early onset (N = 21) and a late onset (N = 19), and their respective age-matched control groups, using the greyscales task, a sensitive measure of asymmetries in visual processing. The stimuli consisted of two rectangles, one above the other, shaded in opposite directions and matched overall for darkness. Participants judged which of the two rectangles looked darker overall. Previous studies using this task in healthy participants have reported a reliable bias, such that the rectangle with the darker end on the left is selected preferentially. Whereas the late-onset patients in this study exhibited a perceptual bias of similar direction and magnitude to that of controls, this was not the case for the early-onset patients, who exhibited significantly less bias than their control group. The reduced perceptual bias seen in the early-onset group, but not the late-onset group, suggests an attenuation of right hemisphere mechanisms dedicated to processing visuospatial information. The attenuated perceptual asymmetry in the early-onset group only may be consistent with the view that (i) an earlier illness onset reflects a greater loss of hemispheric differentiation and (ii) reduced functional asymmetries in the early-onset group are a manifestation of a failure to allocate functions to one or the other hemisphere.

Estimating 241Am activity in the body: comparison of direct measurements and radiochemical analyses

The assessment of dose and ultimately the health risk from intakes of radioactive materials begins with estimating the amount actually taken into the body. An accurate estimate provides the basis to best assess the distribution in the body, the resulting dose and ultimately the health risk. This study continues the time-honoured practice of evaluating the accuracy of results obtained using in vivo measurement methods and techniques. Results from the radiochemical analyses of the (241)Am activity content of tissues and organs from four donors to the United States Transuranium and Uranium Registries (USTUR) were compared with the results from direct measurements of radioactive material in the body performed in vivo and post-mortem. Two were whole-body donations and two were partial-body donations. The (241)Am lung activity estimates ranged from 1 to 30 Bq in the four cases. The (241)Am activity in the lungs determined from the direct measurements were within 40% of the radiochemistry results in three cases and within a factor of 2 for the other case. However, in one case the post-mortem direct measurement estimate was a factor of 10 higher than the radiochemistry result for lung activity, most probably due to underestimating the skeletal contribution to the measured count rate over the lungs. The direct measurement estimates of liver activity ranged from 2 to 60 Bq and were consistently lower than the radiochemistry results. The skeleton was the organ with the highest deposition of (241)Am activity in all four cases. The skeletal activity estimates ranged from 30 to 300 Bq. The skeletal activity obtained from measurements over the forehead were within 20% of the radiochemistry results in three cases and differed by 78% in the other case. The results from this study suggest that the measurement methods, data analysis methods and calibration techniques used at the In Vivo Radiobioassay and Research Facility can be used to quantify the activity in the lungs, skeleton and liver when (241)Am activity is present in all three organs. The adjustment method used to account for the contribution from activity in other organs improved the agreement between the direct measurement results and the radiochemistry results for activity in the lungs and skeleton. The method appeared to overestimate the contribution from the other organs to the liver activity measurements, although the low activity levels complicated the analysis. The unadjusted liver activity estimates from the direct measurements were generally in better agreement with the radiochemistry results than the adjusted liver activity. The data from this study indicates that the results from the in vivo measurement techniques provide reasonable estimates of radioactive material in the lungs and skeleton under the most challenging conditions where there is (241)Am activity in multiple organs. The data analysis from additional USTUR cases with both direct measurement results and radiochemistry results is in progress to further evaluate how best to account for the contributions from (241)Am activity in multiple organs and to better understand the uncertainty associated with the adjusted activity.

A Preliminary Community Study of Dialectical Behaviour Therapy (DBT) with Adolescent Females Demonstrating Persistent, Deliberate Self-Harm (DSH)

A study of dialectical behaviour therapy (DBT) for 16 older female adolescents with persistent and severe deliberate self-harm was undertaken. Independent assessments were carried out pre- and post-treatment, and at eight months follow-up. On average subjects completed more than 78% of sessions. There was a marked reduction in self reported depression (F = 12.8, df = 2, p < .001); hopelessness (F = 15.9, df = 2, p < .001); episodes of deliberate self-harm (F = 23.9, df = 2, p < .001); alongside an increase in general functioning (F = 22.9, df = 2, p < .001).

USTUR whole body case 0262: 33-y follow-up of PuO2 in a skin wound and associated axillary node

This whole body donation case (USTUR Registrant) involved two suspected PuO2 inhalation intakes, each indicated by a measurable Pu alpha activity in a single urine sample, followed about 1(1/2) y later by a puncture wound to the thumb while working in a Pu glovebox. The study is concerned with modelling simultaneously the biokinetics of deposition and retention in the respiratory tract and at the wound site; and the biokinetics of Pu subsequently transferred to other body organs, until the donor's death. Urine samples taken after the wound incident had readily measurable Pu alpha activity over the next 14 y, before dropping below the minimum detectable excretion rate (<0.4 mBq d(-1)). The Registrant died about 33 y after the wound intake, at the age of 71, from hepatocellular carcinoma with extensive metastases. At autopsy, all major soft tissue organs were harvested for analysis of their 238Pu, 239+240Pu and 241Am content. The amount of 239+240Pu retained at the wound site was 68 +/- 7 Bq (1 SD), measured by low-energy planar Ge spectrometry. A further 56.0 +/- 1.2 Bq was retained in an associated axillary lymph node, measured by radiochemistry. Simultaneous mathematical analysis (modelling) of all in vivo urinary excretion data, together with the measured lung, thoracic lymph node, wound, axillary lymph node and systemic tissue contents at death, yielded estimated intake amounts of 757 and 1504 Bq, respectively, for the first and second inhalation incidents, and 204 Bq for the total wound intake. The inhaled Pu material was highly insoluble, with an estimated long-term absorption rate from the lungs of 2 x 10(-5) d(-1). The Pu material deposited at the wound site was mixed: approximately 14% was rapidly absorbed, approximately 49% was absorbed at the rate of about 6 x 10(-5) d(-1), and the remainder ( approximately 37%) was absorbed extremely slowly (at the rate of about 5 x 10(-6) d(-1)). Thus, it was estimated that only approximately 40% of the Pu initially deposited in the wound had been absorbed systemically over the 33-y period until the donor's death. The biokinetic modelling also indicated that, in this individual case, some of the parameter values (rate constants) incorporated in the ICRP Publication 67 Pu model were up to a factor of 2 different from ICRP's recommended values (for reference man).

Ustur whole body case 0269: demonstrating effectiveness of i.v. CA-DTPA for Pu

This whole body donation case (USTUR Registrant) involved a single acute inhalation of an acidic Pu(NO3)4 solution in the form of an aerosol 'mist'. Chelation treatment with intravenously (i.v.) Ca-EDTA was initiated on the day of the intake, and continued intermittently over 6 months. After 2.5 y with no further treatment, a course of i.v. Ca-DTPA was administered. A total of 400 measurements of 239+240Pu excreted in urine were recorded; starting on the first day (both before and during the initial Ca-EDTA chelation) and continuing for 37 y. This sampling included all intervals of chelation. In addition, 91 measurements of 239+240Pu-in-feces were recorded over this whole period. The Registrant died about 38 y after the intake, at age 79 y, with extensive carcinomatosis secondary to adenocarcinoma of the prostate gland. At autopsy, all major soft tissue organs were harvested for radiochemical analyses of their 238Pu, 239+240Pu and 241Am content. Also, all types of bone (comprising about half the skeleton) were harvested for radiochemical analyses, as well as samples of skin, subcutaneous fat and muscle. This comprehensive data set has been applied to derive 'chelation-enhanced' transfer rates in the ICRP Publication 67 plutonium biokinetic model, representing the behaviour of blood-borne and tissue-incorporated plutonium during intervals of therapy. The resulting model of the separate effects of i.v. Ca-EDTA and Ca-DTPA chelation shows that the therapy administered in this case succeeded in reducing substantially the long-term burden of plutonium in all body organs, except for the lungs. The calculated reductions in organ content at the time of death are approximately 40% for the liver, 60% for other soft tissues (muscle, skin, glands, etc.), 50% for the kidneys and 50% for the skeleton. Essentially, all of the substantial reduction in skeletal burden occurred in trabecular bone. This modelling exercise demonstrated that 3-y-delayed Ca-DTPA therapy was as effective as promptly administered Ca-EDTA.

Changes in white matter microstructure during adolescence

Postmortem histological studies have demonstrated that myelination in human brain white matter (WM) continues throughout adolescence and well into adulthood. We used in vivo diffusion-weighted magnetic resonance imaging to test for age-related WM changes in 42 adolescents and 20 young adults. Tract-Based Spatial Statistics (TBSS) analysis of the adolescent data identified widespread age-related increases in fractional anisotropy (FA) that were most significant in clusters including the body of the corpus callosum and right superior corona radiata. These changes were driven by changes in perpendicular, rather than parallel, diffusivity. These WM clusters were used as seeds for probabilistic tractography, allowing us to identify the regions as belonging to callosal, corticospinal, and prefrontal tracts. We also performed voxel-based morphometry-style analysis of conventional T1-weighted images to test for age-related changes in grey matter (GM). We identified a cluster including right middle frontal and precentral gyri that showed an age-related decrease in GM density through adolescence and connected with the tracts showing age-related WM FA increases. The GM density decrease was highly significantly correlated with the WM FA increase in the connected cluster. Age-related changes in FA were much less prominent in the young adult group, but we did find a significant age-related increase in FA in the right superior longitudinal fascicle, suggesting that structural development of this pathway continues into adulthood. Our results suggest that significant microstructural changes in WM continue throughout adolescence and are associated with corresponding age-related changes in cortical GM regions.

IMBA Professional Plus: a flexible approach to internal dosimetry

IMBA (Integrated Modules for Bioassay Analysis) is a suite of software modules that implement the current ICRP biokinetic and dosimetric models for estimation of intakes and doses. The IMBA modules have gone through extensive quality assurance, and are now used for routine formal dose assessment by Approved Dosimetry Services throughout the UK. HPA has continued to develop the IMBA modules. In addition, several projects, sponsored by organisations both in the USA and in Canada, have resulted in the development of customised user-friendly interfaces (IMBA Expert 'editions'). These enable users not only to use the standard ICRP models, but also to change many of the parameter values from ICRP defaults, and to apply sophisticated data handling techniques to internal dose calculations. These include: fitting measurement data with the maximum likelihood method; using multiple chronic and acute intakes; and dealing with different data types, such as urine, faces and whole body simultaneously. These interfaces were improved further as a result of user-feedback, and a general 'off-the-shelf' product, IMBA Professional, was developed and made available in January 2004. A new version, IMBA Professional Plus, was released in April 2005, which is both faster and more powerful than previous software. The aim of this paper is to describe the capabilities of IMBA Professional Plus, and the mathematical methods used.

Retinotopic distribution of chromatic responses in human primary visual cortex

In non-human primates at least three anatomically and functionally distinct channels convey signals from the retina to the primary visual cortex (V1). Two of these channels, the parvocellular and the koniocellular, are sensitive to chromatic contrasts and form the basis of color vision. In humans, common phylogenetic history with other primates and psychophysical experiments suggest identical retinocortical mechanisms but separate evaluation of the distinct anatomical channels has been difficult because signals are already combined in V1. We studied the spatial distribution of activation to chromatic stimuli along the two opponent chromatic axes in human V1 with multifocal functional magnetic resonance imaging. The signal strength was quantified from three experiments with stimuli up to 20 degrees eccentricity. The hypothesis was that, although the parvo- and koniocellular signals are mixed in V1, distinct distributions of signal strength would be evident. We found that whereas different conditions activated the same areas of cortex, indicating that they have identical magnification factors, the responses to red/green stimulation were stronger close to the fovea whereas the blue/yellow responses were much less diminished with increasing eccentricity. Both chromatic axes showed saturating contrast response functions. Our measure directly from human V1 is in line with earlier psychophysical studies suggesting relatively stronger parvocellular channel representation close to the fovea, and more uniform distribution of the koniocellular and achromatic channels. In addition, our study presents a way to rapidly quantify retinotopic signal transmission in distinct retinocortical pathways of individual subjects.

Radon Exposure Assessment and Dosimetry Applied to Epidemiology and Risk Estimation

Epidemiological studies of underground miners provide the primary basis for radon risk estimates for indoor exposures as well as mine exposures. A major source of uncertainty in these risk estimates is the uncertainty in radon progeny exposure estimates for the miners. Often the exposure information is very incomplete, and exposure estimation must rely on interpolations, extrapolations and reconstruction of mining conditions decades before, which might differ markedly from those in more recent times. Many of the measurements that were carried out-commonly for health protection purposes-are not likely to be representative of actual exposures. Early monitoring was often of radon gas rather than of the progeny, so that quantifying exposure requires an estimate of the equilibrium fraction under the conditions existing at the time of the reported measurement. In addition to the uncertainty in radon progeny exposure, doses from gamma radiation, inhaled radioactive dust, and thoron progeny have historically been neglected. These may induce a systematic bias in risk estimates and add to the overall uncertainty in risk estimates derived from the miner studies. Unlike other radiogenic cancer risk estimates, numerical risk estimates derived for radon from epidemiology are usually expressed as a risk per unit exposure rather than as a risk per unit dose to a target tissue. Nevertheless, dosimetric considerations are important when trying to compare risks under different exposure conditions, e.g. in mines and homes. A recent comparative assessment of exposure conditions indicates that, for equal radon progeny exposures, the dose in homes is about the same as in mines. Thus, neglecting other possible differences, such as the presence in mines of other potential airborne carcinogens, the risk per unit progeny exposure should be about the same for indoor exposures as observed in miners. Results of case-control studies of lung cancer incidence in homes monitored for radon are reasonably consistent with what would be projected from miner studies. Measurements of exposure in these indoor case-control studies rely on different types of detectors than those used in mines, and the estimates of exposure are again a major source of uncertainty in these studies.

Multifocal fMRI mapping of visual cortical areas

The multifocal mapping of electroretinograms and visual evoked potentials has established an important role in both basic research and in diagnostic procedures. We have developed a multifocal mapping method for fMRI, which allows detailed analysis of multiple local visual field representations in the cortex with excellent spatial resolution. Visual field was divided into 60 regions in a dartboard configuration, scaled according to the human magnification factor. Within blocks of 7 s, half of the regions were stimulated with checkerboard patterns contrast reversing at 8 reversals per second, while the other half remained inactive at uniform luminance. The subset of active regions changed with each 7-s block, according to an orthogonal design. Functional MRI was done with a 3-T GE Signa and analyzed with SPM2. A general linear model was fitted producing activation maps for each of the 60 regions, and local signal changes were quantified from V1. These activation maps were next assigned to 3D surface models of the cortical sheet, and then unfolded, using the Brain à la Carte software package. Phase-encoded retinotopic analysis of conventional design served as qualitative comparison data. With multifocal fMRI, all regions were mapped with good signal-to-noise ratio in V1, and subsets of regions showed activation in V2 and V3. This method allows rapid and direct exploration of multiple local visual responses, and is thus able to give complementary information to phase encoded mapping of retinotopic areas.

Cerebellar, prefrontal cortex, and thalamic volumes over two time points in adolescent-onset schizophrenia

OBJECTIVE

Structural and functional studies implicate multiple brain lesions as a basis for a functional dysconnectivity underlying the cognitive and symptom profiles in schizophrenia. The aim of this study was to examine the hypothesis that early-onset schizophrenia is associated with structural abnormalities in the prefrontal cortex, thalamus, and cerebellum, compatible with a dysconnectivity syndrome.

METHOD

Two magnetic resonance imaging scans of 16 patients and 16 normal comparison subjects were undertaken on average 2 to 3 years apart. The participants were all from a defined geographic area in the United Kingdom with a population of 2.5 million.

RESULTS

In comparison to the normal adolescents, the schizophrenic subjects demonstrated low prefrontal cortex and thalamic volumes. The relatively large difference in prefrontal and thalamic volumes in these adolescents with schizophrenia implies a more severe disease process than in adult subjects.

CONCLUSIONS

The thalamic and frontal lobe findings provide preliminary, supportive structural evidence for a neurodevelopmental basis for a dysconnectivity syndrome, although the cerebellar findings were inconclusive.

Binary and ternary textures containing higher-order spatial correlations

A quantitative method is presented for creating a large number of classes of binary (256) and ternary (7.62 x 10(12)) textures. The binary textures are presented as black and white (contrasts -1 and 1). The ternary textures have three levels: black, white and the mean luminance gray (contrasts -1, 0 and 1). The ternary patterns in particular display a wide variety of properties, including depth cues from disparity and lighting. Given the very large number of ternary patterns, we present guidelines and analytical methods for selecting sets of textures with particular image qualities and/or nonlinear relationships between pixels. The second- and third-order correlation functions of several thousand examples were examined to reveal patterns that are functionally isotrigon with other textures and or with uniformly distributed noise patterns.

Comparative dosimetry of BEIR VI revisited

The BEIR VI Committee applied recent developments in the comparative dosimetry of radon exposures in mines and homes to evaluate the so-called K-factor used to extrapolate the excess relative risk of lung cancer determined for underground uranium miners to exposures in homes. This paper describes methodological aspects of these developments that were specified ambiguously in the BEIR VI report. Specifically, in the section dealing with dosimetry (Appendix B of the BEIR VI report), the K-factor was unusually defined in terms of exposure to radon gas (K(gas)), and not in terms of exposure to potential alpha energy (K). An incorrect value of unity was calculated for K(gas). This implies a value of 0.44 for K. In this paper, we describe how application of the ICRP Publication 66 lung and dosimetric models to evaluate the regional lung dose per unit exposure to potential alpha-energy in mines and homes yields the value of K = unity. This confirms the BEIR VI Committee's choice of K = 1 for application in their risk extrapolation model. The paper also reviews the use of doses to specific sub-cellular targets in the evaluation of K. This yields a somewhat greater divergence in the corresponding estimates of K, but again an overall average value of K = unity. The paper describes the methods used to calculate alpha particle hit probabilities for specific subcellular targets, and the resulting estimates of single- and multiple-hit probabilities obtained for exposures in mines and homes, as a function of the respective exposure rates.