Executive Control and Associated Brain Activity in Children With Familial High-Risk of Schizophrenia or Bipolar Disorder: A Danish Register-based Study

BACKGROUND AND HYPOTHESES

Impaired executive control is a potential prognostic and endophenotypic marker of schizophrenia (SZ) and bipolar disorder (BP). Assessing children with familial high-risk (FHR) of SZ or BP enables characterization of early risk markers and we hypothesize that they express impaired executive control as well as aberrant brain activation compared to population-based control (PBC) children.

STUDY DESIGN

Using a flanker task, we examined executive control together with functional magnetic resonance imaging (fMRI) in 11- to 12-year-old children with FHR of SZ (FHR-SZ) or FHR of BP (FHR-BP) and PBC children as part of a register-based, prospective cohort-study; The Danish High Risk and Resilience study-VIA 11.

STUDY RESULTS

We included 85 (44% female) FHR-SZ, 63 (52% female) FHR-BP and 98 (50% female) PBC in the analyses. Executive control effects, caused by the spatial visuomotor conflict, showed no differences between groups. Bayesian ANOVA of reaction time (RT) variability, quantified by the coefficient of variation (CVRT), revealed a group effect with similarly higher CVRT in FHR-BP and FHR-SZ compared to PBC (BF10 = 6.82). The fMRI analyses revealed no evidence for between-group differences in task-related brain activation. Post hoc analyses excluding children with psychiatric illness yielded same results.

CONCLUSION

FHR-SZ and FHR-BP at age 11-12 show intact ability to resolve a spatial visuomotor conflict and neural efficacy. The increased variability in RT may reflect difficulties in maintaining sustained attention. Since variability in RT was independent of existing psychiatric illness, it may reflect a potential endophenotypic marker of risk.

Children at Familial High risk of Schizophrenia and Bipolar Disorder Exhibit Altered Connectivity Patterns During Pre-attentive Processing of an Auditory Prediction Error

BACKGROUND AND HYPOTHESIS

Individuals with schizophrenia or bipolar disorder have attenuated auditory mismatch negativity (MMN) responses, indicating impaired sensory information processing. Computational models of effective connectivity between brain areas underlying MMN responses show reduced connectivity between fronto-temporal areas in individuals with schizophrenia. Here we ask whether children at familial high risk (FHR) of developing a serious mental disorder show similar alterations.

STUDY DESIGN

We recruited 67 children at FHR for schizophrenia, 47 children at FHR for bipolar disorder as well as 59 matched population-based controls from the Danish High Risk and Resilience study. The 11-12-year-old participants engaged in a classical auditory MMN paradigm with deviations in frequency, duration, or frequency and duration, while we recorded their EEG. We used dynamic causal modeling (DCM) to infer on the effective connectivity between brain areas underlying MMN.

STUDY RESULTS

DCM yielded strong evidence for differences in effective connectivity among groups in connections from right inferior frontal gyrus (IFG) to right superior temporal gyrus (STG), along with differences in intrinsic connectivity within primary auditory cortex (A1). Critically, the 2 high-risk groups differed in intrinsic connectivity in left STG and IFG as well as effective connectivity from right A1 to right STG. Results persisted even when controlling for past or present psychiatric diagnoses.

CONCLUSIONS

We provide novel evidence that connectivity underlying MMN responses in children at FHR for schizophrenia and bipolar disorder is altered at the age of 11-12, echoing findings that have been found in individuals with manifest schizophrenia.

No phenotypic or genotypic evidence for a link between sleep duration and brain atrophy

Short sleep is held to cause poorer brain health, but is short sleep associated with higher rates of brain structural decline? Analysing 8,153 longitudinal MRIs from 3,893 healthy adults, we found no evidence for an association between sleep duration and brain atrophy. In contrast, cross-sectional analyses (51,295 observations) showed inverse U-shaped relationships, where a duration of 6.5 (95% confidence interval, (5.7, 7.3)) hours was associated with the thickest cortex and largest volumes relative to intracranial volume. This fits converging evidence from research on mortality, health and cognition that points to roughly seven hours being associated with good health. Genome-wide association analyses suggested that genes associated with longer sleep for below-average sleepers were linked to shorter sleep for above-average sleepers. Mendelian randomization did not yield evidence for causal impacts of sleep on brain structure. The combined results challenge the notion that habitual short sleep causes brain atrophy, suggesting that normal brains promote adequate sleep duration-which is shorter than current recommendations.

Cerebral Palsy - Early Diagnosis and Intervention Trial: protocol for the prospective multicentre CP-EDIT study with focus on diagnosis, prognostic factors, and intervention

BACKGROUND

Early diagnosis of cerebral palsy (CP) is important to enable intervention at a time when neuroplasticity is at its highest. Current mean age at diagnosis is 13 months in Denmark. Recent research has documented that an early-diagnosis set-up can lower diagnostic age in high-risk infants. The aim of the current study is to lower diagnostic age of CP regardless of neonatal risk factors. Additionally, we want to investigate if an early intervention program added to standard care is superior to standard care alone.

METHODS

The current multicentre study CP-EDIT (Early Diagnosis and Intervention Trial) with the GO-PLAY intervention included (Goal Oriented ParentaL supported home ActivitY program), aims at testing the feasibility of an early diagnosis set-up and the GO-PLAY early intervention. CP-EDIT is a prospective cohort study, consecutively assessing approximately 500 infants at risk of CP. We will systematically collect data at inclusion (age 3-11 months) and follow a subset of participants (n = 300) with CP or at high risk of CP until the age of two years. The GO-PLAY early intervention will be tested in 80 infants with CP or high risk of CP. Focus is on eight areas related to implementation and perspectives of the families: early cerebral magnetic resonance imaging (MRI), early genetic testing, implementation of the General Movements Assessment method, analysis of the GO-PLAY early intervention, parental perspective of early intervention and early diagnosis, early prediction of CP, and comparative analysis of the Hand Assessment for Infants, Hammersmith Infant Neurological Examination, MRI, and the General Movements method.

DISCUSSION

Early screening for CP is increasingly possible and an interim diagnosis of "high risk of CP" is recommended but not currently used in clinical care in Denmark. Additionally, there is a need to accelerate identification in mild or ambiguous cases to facilitate appropriate therapy early. Most studies on early diagnosis focus on identifying CP in infants below five months corrected age. Little is known about early diagnosis in the 50% of all CP cases that are discernible later in infancy. The current study aims at improving care of patients with CP even before they have an established diagnosis.

TRIAL REGISTRATION

ClinicalTrials.gov ID 22013292 (reg. date 31/MAR/2023) for the CP-EDIT cohort and ID 22041835 (reg. date 31/MAR/2023) for the GO-PLAY trial.

Lifestyle-related risk factors and their cumulative associations with hippocampal and total grey matter volume across the adult lifespan: A pooled analysis in the European Lifebrain consortium

BACKGROUND

Lifestyle-related risk factors, such as obesity, physical inactivity, short sleep, smoking and alcohol use, have been associated with low hippocampal and total grey matter volumes (GMV). However, these risk factors have mostly been assessed as separate factors, leaving it unknown if variance explained by these factors is overlapping or additive. We investigated associations of five lifestyle-related factors separately and cumulatively with hippocampal and total GMV, pooled across eight European cohorts.

METHODS

We included 3838 participants aged 18-90 years from eight cohorts of the European Lifebrain consortium. Using individual person data, we performed cross-sectional meta-analyses on associations of presence of lifestyle-related risk factors separately (overweight/obesity, physical inactivity, short sleep, smoking, high alcohol use) as well as a cumulative unhealthy lifestyle score (counting the number of present lifestyle-related risk factors) with FreeSurfer-derived hippocampal volume and total GMV. Lifestyle-related risk factors were defined according to public health guidelines.

RESULTS

High alcohol use was associated with lower hippocampal volume (r = -0.10, p = 0.021), and overweight/obesity with lower total GMV (r = -0.09, p = 0.001). Other lifestyle-related risk factors were not significantly associated with hippocampal volume or GMV. The cumulative unhealthy lifestyle score was negatively associated with total GMV (r = -0.08, p = 0.001), but not hippocampal volume (r = -0.01, p = 0.625).

CONCLUSIONS

This large pooled study confirmed the negative association of some lifestyle-related risk factors with hippocampal volume and GMV, although with small effect sizes. Lifestyle factors should not be seen in isolation as there is evidence that having multiple unhealthy lifestyle factors is associated with a linear reduction in overall brain volume.

Is Short Sleep Bad for the Brain? Brain Structure and Cognitive Function in Short Sleepers

Many sleep less than recommended without experiencing daytime sleepiness. According to prevailing views, short sleep increases risk of lower brain health and cognitive function. Chronic mild sleep deprivation could cause undetected sleep debt, negatively affecting cognitive function and brain health. However, it is possible that some have less sleep need and are more resistant to negative effects of sleep loss. We investigated this using a cross-sectional and longitudinal sample of 47,029 participants of both sexes (20-89 years) from the Lifebrain consortium, Human Connectome project (HCP) and UK Biobank (UKB), with measures of self-reported sleep, including 51,295 MRIs of the brain and cognitive tests. A total of 740 participants who reported to sleep <6 h did not experience daytime sleepiness or sleep problems/disturbances interfering with falling or staying asleep. These short sleepers showed significantly larger regional brain volumes than both short sleepers with daytime sleepiness and sleep problems (n = 1742) and participants sleeping the recommended 7-8 h (n = 3886). However, both groups of short sleepers showed slightly lower general cognitive function (GCA), 0.16 and 0.19 SDs, respectively. Analyses using accelerometer-estimated sleep duration confirmed the findings, and the associations remained after controlling for body mass index, depression symptoms, income, and education. The results suggest that some people can cope with less sleep without obvious negative associations with brain morphometry and that sleepiness and sleep problems may be more related to brain structural differences than duration. However, the slightly lower performance on tests of general cognitive abilities warrants closer examination in natural settings.SIGNIFICANCE STATEMENT Short habitual sleep is prevalent, with unknown consequences for brain health and cognitive performance. Here, we show that daytime sleepiness and sleep problems are more strongly related to regional brain volumes than sleep duration. However, participants sleeping ≤6 h had slightly lower scores on tests of general cognitive function (GCA). This indicates that sleep need is individual and that sleep duration per se is very weakly if at all related brain health, while daytime sleepiness and sleep problems may show somewhat stronger associations. The association between habitual short sleep and lower scores on tests of general cognitive abilities must be further scrutinized in natural settings.

Individual differences in brain aging: heterogeneity in cortico-hippocampal but not caudate atrophy rates

It is well documented that some brain regions, such as association cortices, caudate, and hippocampus, are particularly prone to age-related atrophy, but it has been hypothesized that there are individual differences in atrophy profiles. Here, we document heterogeneity in regional-atrophy patterns using latent-profile analysis of 1,482 longitudinal magnetic resonance imaging observations. The results supported a 2-group solution reflecting differences in atrophy rates in cortical regions and hippocampus along with comparable caudate atrophy. The higher-atrophy group had the most marked atrophy in hippocampus and also lower episodic memory, and their normal caudate atrophy rate was accompanied by larger baseline volumes. Our findings support and refine models of heterogeneity in brain aging and suggest distinct mechanisms of atrophy in striatal versus hippocampal-cortical systems.

Hippocampal anterior- posterior shift in childhood and adolescence

Hippocampal-cortical networks play an important role in neurocognitive development. Applying the method of Connectivity-Based Parcellation (CBP) on hippocampal-cortical structural covariance (SC) networks computed from T1-weighted magnetic resonance images, we examined how the hippocampus differentiates into subregions during childhood and adolescence (N = 1105, 6-18 years). In late childhood, the hippocampus mainly differentiated along the anterior-posterior axis similar to previous reported functional differentiation patterns of the hippocampus. In contrast, in adolescence a differentiation along the medial-lateral axis was evident, reminiscent of the cytoarchitectonic division into cornu ammonis and subiculum. Further meta-analytical characterization of hippocampal subregions in terms of related structural co-maturation networks, behavioural and gene profiling suggested that the hippocampal head is related to higher order functions (e.g. language, theory of mind, autobiographical memory) in late childhood morphologically co-varying with almost the whole brain. In early adolescence but not in childhood, posterior subicular SC networks were associated with action-oriented and reward systems. The findings point to late childhood as an important developmental period for hippocampal head morphology and to early adolescence as a crucial period for hippocampal integration into action- and reward-oriented cognition. The latter may constitute a developmental feature that conveys increased propensity for addictive disorders.

Stability of associations between neuroticism and microstructural asymmetry of the cingulum during late childhood and adolescence: Insights from a longitudinal study with up to 11 waves

Adolescence is characterized by significant brain development and marks a period of the life span with an increased incidence of mood disorders, especially in females. The risk of developing mood disorders is also higher in individuals scoring high on neuroticism, a personality trait characterized by a tendency to experience negative and anxious emotions. We previously found in a cross-sectional study that neuroticism is associated with microstructural left-right asymmetry of the fronto-limbic white matter involved in emotional processing, with opposite effects in female and male adolescents. We now have extended this work collecting longitudinal data in 76 typically developing children and adolescents aged 7-18 years, including repeated MRI sampling up to 11 times. This enabled us, for the first time, to address the critical question, whether the association between neuroticism and frontal-limbic white matter asymmetry changes or remains stable across late childhood and adolescence. Neuroticism was assessed up to four times and showed good intraindividual stability and did not significantly change with age. Conforming our cross-sectional results, females scoring high on neuroticism displayed increased left-right cingulum fractional anisotropy (FA), while males showed decreased left-right cingulum FA asymmetry. Despite ongoing age-related increases in FA in cingulum, the association between neuroticism and cingulum FA asymmetry was already expressed in females in late childhood and remained stable across adolescence. In males, the association appeared to become more prominent during adolescence. Future longitudinal studies need to cover an earlier age span to elucidate the time point at which the relationship between neuroticism and cingulum FA asymmetry arises.

People's interest in brain health testing: Findings from an international, online cross-sectional survey

Brain health entails mental wellbeing and cognitive health in the absence of brain disorders. The past decade has seen an explosion of tests, cognitive and biological, to predict various brain conditions, such as Alzheimer's Disease. In line with these current developments, we investigated people's willingness and reasons to-or not to-take a hypothetical brain health test to learn about risk of developing a brain disease, in a cross-sectional multilanguage online survey. The survey was part of the Global Brain Health Survey, open to the public from 4th June 2019 to 31st August 2020. Respondents were largely recruited via European brain councils and research organizations. 27,590 people responded aged 18 years or older and were predominantly women (71%), middle-aged or older (>40 years; 83%), and highly educated (69%). Responses were analyzed to explore the relationship between demographic variables and responses.

Results

We found high public interest in brain health testing: over 91% would definitely or probably take a brain health test and 86% would do so even if it gave information about a disease that cannot be treated or prevented. The main reason for taking a test was the ability to respond if one was found to be at risk of brain disease, such as changing lifestyle, seeking counseling or starting treatment. Higher interest in brain health testing was found in men, respondents with lower education levels and those with poor self-reported cognitive health.

Conclusion

High public interest in brain health and brain health testing in certain segments of society, coupled with an increase of commercial tests entering the market, is likely to put pressure on public health systems to inform the public about brain health testing in years to come.

Associations of depression and regional brain structure across the adult lifespan: Pooled analyses of six population-based and two clinical cohort studies in the European Lifebrain consortium

OBJECTIVE

Major depressive disorder has been associated with lower prefrontal thickness and hippocampal volume, but it is unknown whether this association also holds for depressive symptoms in the general population. We investigated associations of depressive symptoms and depression status with brain structures across population-based and patient-control cohorts, and explored whether these associations are similar over the lifespan and across sexes.

METHODS

We included 3,447 participants aged 18-89 years from six population-based and two clinical patient-control cohorts of the European Lifebrain consortium. Cross-sectional meta-analyses using individual person data were performed for associations of depressive symptoms and depression status with FreeSurfer-derived thickness of bilateral rostral anterior cingulate cortex (rACC) and medial orbitofrontal cortex (mOFC), and hippocampal and total grey matter volume (GMV), separately for population-based and clinical cohorts.

RESULTS

Across patient-control cohorts, depressive symptoms and presence of mild-to-severe depression were associated with lower mOFC thickness (r_symptoms = -0.15/ r_status = -0.22), rACC thickness (r_symptoms = -0.20/ r_status = -0.25), hippocampal volume (r_symptoms = -0.13/ r_status = 0.13) and total GMV (r_symptoms = -0.21/ r_status = -0.25). Effect sizes were slightly larger for presence of moderate-to-severe depression. Associations were similar across age groups and sex. Across population-based cohorts, no associations between depression and brain structures were observed.

CONCLUSIONS

Fitting with previous meta-analyses, depressive symptoms and depression status were associated with lower mOFC, rACC thickness, and hippocampal and total grey matter volume in clinical patient-control cohorts, although effect sizes were small. The absence of consistent associations in population-based cohorts with mostly mild depressive symptoms, suggests that significantly lower thickness and volume of the studied brain structures are only detectable in clinical populations with more severe depressive symptoms.

Brain aging differs with cognitive ability regardless of education

Higher general cognitive ability (GCA) is associated with lower risk of neurodegenerative disorders, but neural mechanisms are unknown. GCA could be associated with more cortical tissue, from young age, i.e. brain reserve, or less cortical atrophy in adulthood, i.e. brain maintenance. Controlling for education, we investigated the relative association of GCA with reserve and maintenance of cortical volume, -area and -thickness through the adult lifespan, using multiple longitudinal cognitively healthy brain imaging cohorts (n = 3327, 7002 MRI scans, baseline age 20-88 years, followed-up for up to 11 years). There were widespread positive relationships between GCA and cortical characteristics (level-level associations). In select regions, higher baseline GCA was associated with less atrophy over time (level-change associations). Relationships remained when controlling for polygenic scores for both GCA and education. Our findings suggest that higher GCA is associated with cortical volumes by both brain reserve and -maintenance mechanisms through the adult lifespan.

The midpoint of cortical thinning between late childhood and early adulthood differs between individuals and brain regions: Evidence from longitudinal modelling in a 12-wave neuroimaging sample

Charting human brain maturation between childhood and adulthood is a fundamental prerequisite for understanding the rapid biological and psychological changes during human development. Two barriers have precluded the quantification of maturational trajectories: demands on data and demands on estimation. Using high-temporal resolution neuroimaging data of up to 12-waves in the HUBU cohort (N = 90, aged 7-21 years) we investigate changes in apparent cortical thickness across childhood and adolescence. Fitting a four-parameter logistic nonlinear random effects mixed model, we quantified the characteristic, s-shaped, trajectory of cortical thinning in adolescence. This approach yields biologically meaningful parameters, including the midpoint of cortical thinning (MCT), which corresponds to the age at which the cortex shows most rapid thinning - in our sample occurring, on average, at 14 years of age. These results show that, given suitable data and models, cortical maturation can be quantified with precision for each individual and brain region.

Public perceptions of brain health: an international, online cross-sectional survey

OBJECTIVES

To investigate public perspectives on brain health.

DESIGN

Cross-sectional multilanguage online survey.

SETTING

Lifebrain posted the survey on its website and social media and shared it with stakeholders. The survey was open from 4 June 2019 to 31 August 2020.

PARTICIPANTS

n=27 590 aged ≥18 years from 81 countries in five continents completed the survey. The respondents were predominantly women (71%), middle aged (41-60 years; 37%) or above (>60 years; 46%), highly educated (69%) and resided in Europe (98%).

MAIN OUTCOME MEASURES

Respondents' views were assessed regarding factors that may influence brain health, life periods considered important to look after the brain and diseases and disorders associated with the brain. We run exploratory linear models at a 99% level of significance to assess correlates of the outcome variables, adjusting for likely confounders in a targeted fashion.

RESULTS

Of all significant effects, the respondents recognised the impact of lifestyle factors on brain health but had relatively less awareness of the role socioeconomic factors might play. Most respondents rated all life periods as important for the brain (95%-96%), although the prenatal period was ranked significantly lower (84%). Equally, women and highly educated respondents more often rated factors and life periods to be important for brain health. Ninety-nine per cent of respondents associated Alzheimer's disease and dementia with the brain. The respondents made a connection between mental health and the brain, and mental disorders such as schizophrenia and depression were significantly more often considered to be associated with the brain than neurological disorders such as stroke and Parkinson's disease. Few respondents (<32%) associated cancer, hypertension, diabetes and arthritis with the brain.

CONCLUSIONS

Differences in perceptions of brain health were noted among specific segments of the population. Policies providing information about brain-friendly health behaviours and targeting people less likely to have relevant experience may be needed.

No Association Between Loneliness, Episodic Memory and Hippocampal Volume Change in Young and Healthy Older Adults: A Longitudinal European Multicenter Study

Background

Loneliness is most prevalent during adolescence and late life and has been associated with mental health disorders as well as with cognitive decline during aging. Associations between longitudinal measures of loneliness and verbal episodic memory and brain structure should thus be investigated.

Methods

We sought to determine associations between loneliness and verbal episodic memory as well as loneliness and hippocampal volume trajectories across three longitudinal cohorts within the Lifebrain Consortium, including children, adolescents (N = 69, age range 10-15 at baseline examination) and older adults (N = 1468 over 60). We also explored putative loneliness correlates of cortical thinning across the entire cortical mantle.

Results

Loneliness was associated with worsening of verbal episodic memory in one cohort of older adults. Specifically, reporting medium to high levels of loneliness over time was related to significantly increased memory loss at follow-up examinations. The significance of the loneliness-memory change association was lost when eight participants were excluded after having developed dementia in any of the subsequent follow-up assessments. No significant structural brain correlates of loneliness were found, neither hippocampal volume change nor cortical thinning.

Conclusion

In the present longitudinal European multicenter study, the association between loneliness and episodic memory was mainly driven by individuals exhibiting progressive cognitive decline, which reinforces previous findings associating loneliness with cognitive impairment and dementia.

Education and Income Show Heterogeneous Relationships to Lifespan Brain and Cognitive Differences Across European and US Cohorts

Higher socio-economic status (SES) has been proposed to have facilitating and protective effects on brain and cognition. We ask whether relationships between SES, brain volumes and cognitive ability differ across cohorts, by age and national origin. European and US cohorts covering the lifespan were studied (4-97 years, N = 500 000; 54 000 w/brain imaging). There was substantial heterogeneity across cohorts for all associations. Education was positively related to intracranial (ICV) and total gray matter (GM) volume. Income was related to ICV, but not GM. We did not observe reliable differences in associations as a function of age. SES was more strongly related to brain and cognition in US than European cohorts. Sample representativity varies, and this study cannot identify mechanisms underlying differences in associations across cohorts. Differences in neuroanatomical volumes partially explained SES-cognition relationships. SES was more strongly related to ICV than to GM, implying that SES-cognition relations in adulthood are less likely grounded in neuroprotective effects on GM volume in aging. The relatively stronger SES-ICV associations rather are compatible with SES-brain volume relationships being established early in life, as ICV stabilizes in childhood. The findings underscore that SES has no uniform association with, or impact on, brain and cognition.

The Danish High-Risk and Resilience Study-VIA 15 - A Study Protocol for the Third Clinical Assessment of a Cohort of 522 Children Born to Parents Diagnosed With Schizophrenia or Bipolar Disorder and Population-Based Controls

BACKGROUND

Children born to parents with severe mental illness have gained more attention during the last decades because of increasing evidence documenting that these children constitute a population with an increased risk of developing mental illness and other negative life outcomes. Because of high-quality research with cohorts of offspring with familial risk and increased knowledge about gene-environment interactions, early interventions and preventive strategies are now being developed all over the world. Adolescence is a period characterized by massive changes, both in terms of physical, neurologic, psychological, social, and behavioral aspects. It is also the period of life with the highest risk of experiencing onset of a mental disorder. Therefore, investigating the impact of various risk and resilience factors in adolescence is important.

METHODS

The Danish High-Risk and Resilience Study started data collection in 2012, where 522 7-year-old children were enrolled in the first wave of the study, the VIA 7 study. The cohort was identified through Danish registers based on diagnoses of the parents. A total of 202 children had a parent diagnosed with schizophrenia, 120 children had a parent diagnosed with bipolar disorder, and 200 children had parents without these diagnoses. At age 11 years, all children were assessed for the second time in the VIA 11 study, with a follow-up retention rate of 89%. A comprehensive assessment battery covering domains of psychopathology, neurocognition, social cognition and behavior, motor development and physical health, genetic analyses, attachment, stress, parental functioning, and home environment was carried out at each wave. Magnetic resonance imaging scans of the brain and electroencephalograms were included from age 11 years. This study protocol describes the third wave of assessment, the VIA 15 study, participants being 15 years of age and the full, 3-day-long assessment battery this time including also risk behavior, magnetoencephalography, sleep, and a white noise paradigm. Data collection started on May 1, 2021.

DISCUSSION

We will discuss the importance of longitudinal studies and cross-sectional data collection and how studies like this may inform us about unmet needs and windows of opportunity for future preventive interventions, early illness identification, and treatment in the future.

Do outpatients with cancer and their relatives want to use an online booking system to book the appointment and radiographer for their CT examination? A small-scale study in Denmark

INTRODUCTION

Previous studies have found that online booking systems may be the preferred scheduling tool when booking appointments with healthcare providers. The aim of this study was to examine I) if outpatients with cancer and relatives of cancer patients wanted to use an online booking system to book appointments for the CT examinations, and II) if they wanted to book specific radiographers for the CT examinations.

METHODS

An online questionnaire was distributed to outpatients with cancer and relatives of cancer patients registered in the user panel of the Danish Cancer Society. The questionnaires consisted of 13 questions for patients and eight questions for relatives. The study applied statistical analysis and qualitative content analysis with an inductive approach.

RESULTS

In total, 555 patients out of 760 (73%) and 115 out of 341 (34%) relatives were included in the present study and 54% of the patients and 65% of the relatives responded that they wanted, "To a high degree" or "To some degree", to use an online system for booking the appointment of the CT examination. Furthermore, 49% of the patients and 60% of the relatives found it important, "To a high degree" or "To some degree", that the appointment of the CT examination also suited their relatives. Only 37% of the patients, in contrast to 56% of the relatives, were interested in the opportunity to book specific radiographers. Approximately half of the patients (48%) and relatives (58%) were interested in being scanned by the same radiographers.

CONCLUSION

In this study, a majority of patients and relatives were interested in using an online booking system to book their CT examinations. Furthermore, while a majority of the relatives were more interested in booking specific radiographers for the CT examinations, only a few patients were interested in this function.

IMPLICATIONS FOR PRACTICE

Using an online booking system to book the appointment could benefit the overall experience for cancer patients and relatives when attending a CT examination to ensure that the appointment also suits the relatives.

Right-left asymmetry in corticospinal tract microstructure and dexterity are uncoupled in late adulthood

Ageing leads to a decline in white matter microstructure and dexterous function of the hand. In adolescents, it has previously been shown that the degree of right-left asymmetry in the corticospinal tract (CST) is linearly related with right-left asymmetry in dexterity. Here, we tested whether this association is also expressed in older adults. Participants completed a simple circle drawing task with their right and left hand as a measure of dexterity and underwent whole-brain diffusion weighted imaging at 3 Tesla (n = 199; aged 60-72 years). Fractional anisotropy and mean diffusivity of right and left CST were extracted from a manually defined region-of-interest. Linear regression analyses were computed to replicate the analyses in adolescents. Frequentist analyses were complemented with a Bayesian analytical framework. Outcome measures were compared with those previously reported in adolescents (aged 11-16 years). Asymmetries in white matter microstructure of the CST were evident and comparable to the degree of lateralisation observed in adolescence. Similarly, asymmetries in dexterity were evident, but to a lesser degree than in adolescents. Unlike in adolescents, we found no evidence of a linear relationship between asymmetries in CST microstructure and dexterity. Complementary Bayesian regression analysis provided moderate evidence in favour of the null hypothesis, pointing towards a lack of association between the structural and functional measures of right-left asymmetry. Our findings are compatible with the notion that, by late adulthood, a diverging impact of age on white matter structure and dexterous hand function dilutes the structure-function relationship between CST microstructure and manual proficiency that has been reported in adolescents.

Brain structure associations with phonemic and semantic fluency in typically-developing children

Verbal fluency is the ability to retrieve lexical knowledge quickly and efficiently and develops during childhood and adolescence. Few studies have investigated associations between verbal fluency performance and brain structural variation in children. Here we examined associations of verbal fluency performance with structural measures of frontal and temporal language-related brain regions and their connections in 73 typically-developing children aged 7-13 years. Tract-based spatial statistics was used to extract fractional anisotropy (FA) from the superior longitudinal fasciculus/arcuate fasciculus (SLF/AF), and the white matter underlying frontal and temporal language-related regions. FreeSurfer was used to extract cortical thickness and surface area. Better semantic and phonemic fluency performance was associated with higher right SLF/AF FA, and phonemic fluency was also modestly associated with lower left SLF/AF FA. Explorative voxelwise analyses for semantic fluency suggested associations with FA in other fiber tracts, including corpus callosum and right inferior fronto-occipital fasciculus. Overall, our results suggest that verbal fluency performance in children may rely on right hemisphere structures, possibly involving both language and executive function networks, and less on solely left hemisphere structures as often is observed in adults. Longitudinal studies are needed to clarify whether these associations are mediated by maturational processes, stable characteristics and/or experience.

Motor fatigue is associated with asymmetric connectivity properties of the corticospinal tract in multiple sclerosis

Multiple Sclerosis (MS) is characterized by demyelination and neurodegeneration of the central nervous system and causes excessive fatigue in more than 80% of the patients. The pathophysiologic mechanisms causing fatigue are still largely unknown. In 46 right-handed patients with relapsing-remitting MS and 25 right-handed controls, we performed diffusion MRI and applied streamline based probabilistic tractography to derive unilateral anatomical connectivity maps for the white matter of the right and left hemispheres. The maps provide an indication how often a streamline has passed through a given voxel. Since tractography based anatomical connectivity mapping (ACM) is sensitive to disease-induced changes in anatomical connectivity, we used ACM to test whether motor fatigue is associated with altered ipsi-hemispherical anatomical connectivity in the major motor output pathway, the corticospinal tract (CST). Patients had higher mean ACM values in the CST than healthy controls. This indicated that a higher number of streamlines, starting from voxels in the same hemisphere, travelled through the CST and may reflect an accumulated disease-induced disintegration of CST. The motor subscale of the Fatigue Scale for Motor and Cognitive functions (FSMCMOTOR) was used to define sub-groups with (n = 29, FSMCMOTOR score ≥ 27) and without motor fatigue (n = 17, FSMSMOTOR score ≤ 26). Patients without fatigue only showed higher ACM values in right CST, while mean ACM values were unaltered in left CST. The higher the mean ACM values in the left relative to the right CST, the more patients reported motor fatigue. Left-right asymmetry in anatomical connectivity outside the CST did not scale with individual motor fatigue. Our results link lateralized changes of tractography-based microstructural properties in the CST with motor fatigue in relapsing-remitting MS.

The Global Brain Health Survey: Development of a Multi-Language Survey of Public Views on Brain Health

Background: Brain health is a multi-faceted concept used to describe brain physiology, cognitive function, mental health and well-being. Diseases of the brain account for one third of the global burden of disease and are becoming more prevalent as populations age. Diet, social interaction as well as physical and cognitive activity are lifestyle factors that can potentially influence facets of brain health. Yet, there is limited knowledge about the population's awareness of brain health and willingness to change lifestyle to maintain a healthy brain. This paper introduces the Global Brain Health Survey protocol, designed to assess people's perceptions of brain health and factors influencing brain health.

Methods: The Global Brain Health Survey is an anonymous online questionnaire available in 14 languages to anyone above the age of 18 years. Questions focus on (1) willingness and motivation to maintain or improve brain health, (2) interest in learning more about individual brain health using standardized tests, and (3) interest in receiving individualized support to take care of own brain health. The survey questions were developed based on results from a qualitative interview study investigating brain health perceptions among participants in brain research studies. The survey includes 28 questions and takes 15–20 min to complete. Participants provide electronically informed consent prior to participation. The current survey wave was launched on June 4, 2019 and will close on August 31, 2020. We will provide descriptive statistics of samples distributions including analyses of differences as a function of age, gender, education, country of residence, and we will examine associations between items. The European Union funded Lifebrain project leads the survey in collaboration with national brain councils in Norway, Germany, and Belgium, Brain Foundations in the Netherlands and Sweden, the National University of Ostroh Academy and the Women's Brain Project.

Discussion: Results from this survey will provide new insights in peoples' views on brain health, in particular, the extent to which the adoption of positive behaviors can be encouraged. The results will contribute to the development of policy recommendations for supporting population brain health, including measures tailored to individual needs, knowledge, motivations and life situations.

CO-score; a new method for quality assessment of radiology reports

INTRODUCTION

Studies on assessing radiology reports commonly calculates sensitivity, specificity and accuracy, which estimates if the observer has tendency to overdiagnose, overlook pathology, or both. This pilot study examines a new method for assessing the quality of radiology reports, based on the patients' clinical outcome.

METHODS

Two observers evaluated five hundred reports by four experienced reporting radiographers on X-ray images of the appendicular skeleton. The observers categorised the reports as true or false and gradated the quality of the report from 1 to 3 based on the patients' clinical outcome. We developed a new performance score, called the Consequence of Clinical Outcome (CO-score), which combines the amount of incorrect reports and the severity of errors, to assess the overall quality of the reports. A low CO-score represents high quality with few or inconsiderate errors.

RESULTS

The results showed no direct connection between high accuracy and low CO-score. All radiographers achieved high levels of accuracy (range: 96.8%-100%) but varied in CO-score (range: 0.00-0.14). One radiographer achieved an accuracy of 97.6% but a high CO-score of 0.14 as four reports had clinical consequence for the patients and five reports lacked minor details. One report was classified as true positive but was inadequate and led to wrong treatment.

CONCLUSION

This study shows that true reports can affect the patients' clinical outcome and reports classified as false can represent insignificant errors. The new CO-score gives a more nuanced view of the reporting quality by including the patients' clinical outcome in the performance score.

IMPLICATIONS FOR PRACTICE

We suggest that the CO-score is included as a supplement to the common methods in future studies assessing the quality of radiology reports as well as in clinical audits.

Alterations in Task-Related Brain Activation in Children, Adolescents and Young Adults at Familial High-Risk for Schizophrenia or Bipolar Disorder - A Systematic Review

Children, adolescents, and young adults with at least one first-degree relative [familial high-risk (FHR)] with either schizophrenia (SZ) or bipolar disorder (BD) have a one-in-two risk of developing a psychiatric disorder. Here, we review functional magnetic resonance imaging (fMRI) studies which examined task-related brain activity in young individuals with FHR-SZ and FHR-BD. A systematic search identified all published task-related fMRI studies in children, adolescents, and young adults below an age of 27 years with a first-degree relative with SZ or BD, but without manifest psychotic or affective spectrum disorder themselves. The search identified 19 cross-sectional fMRI studies covering four main cognitive domains: 1) working memory (n = 3), 2) cognitive control (n = 4), 3) reward processing (n = 3), and 4) emotion processing (n = 9). Thirteen studies included FHR-BD, five studies included FHR-SZ, and one study included a pooled FHR group. In general, task performance did not differ between the respective FHR groups and healthy controls, but 18 out of the 19 fMRI studies revealed regional alterations in task-related activation. Brain regions showing group differences in peak activation were regions associated with the respective task domain and showed little overlap between FHR-SZ and FHR-BD. The low number of studies, together with the low number of subjects, and the substantial heterogeneity of employed methodological approaches within the domain of working memory, cognitive control, and reward processing impedes finite conclusions. Emotion processing was the most investigated task domain in FHR-BD. Four studies reported differences in activation of the amygdala, and two studies reported differences in activation of inferior frontal/middle gyrus. Together, these studies provide evidence for altered brain processing of emotions in children, adolescents, and young adults at FHR-BD. More studies of higher homogeneity, larger sample sizes and with a longitudinal study design are warranted to prove a shared or specific FHR-related endophenotypic brain activation in young first-degree relatives of individuals with SZ or BD, as well as to pinpoint specific alterations in brain activation during cognitive-, emotional-, and reward-related tasks.

Previous glucocorticoid treatment in childhood and adolescence is associated with long-term differences in subcortical grey matter volume and microstructure

BACKGROUND

Glucocorticoids are widely used in the treatment of several pediatric diseases with undisputed disease-related benefits. Perinatal exposure to high levels of glucocorticoids can have long-term adverse cerebral effects. In adults, glucocorticoid treatment has been associated with smaller volumes of subcortical grey matter structures. Recently, we observed smaller total brain volumes in children and adolescents treated with glucocorticoid during childhood compared to healthy controls. The possible long-term effects of glucocorticoid treatment during childhood on subcortical brain volume and microstructure remain unknown.

METHOD

We examined 30 children and adolescents, who had previously been treated with glucocorticoids for nephrotic syndrome or rheumatic disease, and 30 healthy volunteers. Patients and healthy control groups were matched by age, gender, and level of parent education. Participants underwent 3 T magnetic resonance (MR) brain imaging. T1-weighted and diffusion-weighted images were acquired. Volume and mean diffusivity (MD) measures were extracted for hippocampus, amygdala, nucleus accumbens, caudate nucleus and putamen. Multiple linear regression analyses were used to assess differences between patients and controls, and to evaluate possible dose-response relationships. A priori, we expected patients to display lower hippocampal and amygdala volumes.

RESULTS

While children previously treated with glucocorticoids displayed smaller right hippocampal volumes than controls, this difference did not survive correction for multiple comparisons. Furthermore, patients as compared to controls showed lower right hippocampal MD, which remained when correcting for global changes in MD. The longer the time between the glucocorticoid treatment termination and MR-scan, the more right hippocampal MD values resembled that of healthy controls. Patient and controls did not differ in amygdala volume or MD. Analyses of the nucleus accumbens, caudate nucleus and putamen only revealed smaller putamen volumes in patients compared to controls, which remained significant when controlling for total brain volume.

CONCLUSION

The results suggest that extra-cerebral diseases during childhood treated with glucocorticoids may be associated with reduced subcortical grey matter volumes and lower right hippocampal mean diffusivity later in life. Our findings warrant replication and elaboration in larger, preferably prospective and longitudinal studies. Such studies may also allow disentangling disease-specific effects from possible glucocorticoid treatment effects.

State-dependent alterations in inhibitory control and emotional face identification in seasonal affective disorder

BACKGROUND

Depressed individuals often exhibit impaired inhibition to negative input and identification of positive stimuli, but it is unclear whether this is a state or trait feature. We here exploited a naturalistic model, namely individuals with seasonal affective disorder (SAD), to study this feature longitudinally.

AIM

The goal of this study was to examine seasonal changes in inhibitory control and identification of emotional faces in individuals with SAD.

METHOD

Twenty-nine individuals diagnosed with winter-SAD and 30 demographically matched controls with no seasonality symptoms completed an emotional Go/NoGo task, requiring inhibition of prepotent responses to emotional facial expressions and an emotional face identification task twice, in winter and summer.

RESULTS

In winter, individuals with SAD showed impaired ability to inhibit responses to angry (p = .0006) and sad faces (p = .011), and decreased identification of happy faces (p = .032) compared with controls. In summer, individuals with SAD and controls performed similarly on these tasks (ps > .24).

CONCLUSION

We provide novel evidence that inhibition of angry and sad faces and identification of happy faces are impaired in SAD in the symptomatic phase, but not in the remitted phase. The affective biases in cognitive processing constitute state-dependent features of SAD. Our data show that reinstatement of a normal affective cognition should be possible and would constitute a major goal in psychiatric treatment to improve the quality of life for these patients. (PsycINFO Database Record

Children and adolescents previously treated with glucocorticoids display lower verbal intellectual abilities

AIM

Perinatal exposure to glucocorticoids has been associated with adverse cerebral effects, but little is known about their effect on cognitive development and exposure later in childhood. This study examined intellectual abilities, memory and behavioural problems in children previously treated with glucocorticoids.

METHODS

We evaluated 38 children aged from seven to 16 years, who had been treated with glucocorticoids for rheumatic disease or nephrotic syndrome, together with 42 healthy controls matched for age, gender and parental education. The median cumulative dose of prednisolone equivalents was 158 mg/kg (range 21-723) and the mean time that had elapsed since treatment was three-and-a-half (standard deviation 2.2) years. Intellectual abilities were assessed with the Wechsler Intelligence Scale for Children and memory performance and behavioural problems with a pattern recognition memory task and the Child Behaviour Check List.

RESULTS

There were no significant differences between the groups in pattern recognition memory, perceptual organisation index or behavioural problems, but patients had a significantly lower verbal comprehension index and this difference was present in both disease groups. There were no significant dose-response relationships regarding verbal intellectual abilities.

CONCLUSION

Children and adolescents previously treated with glucocorticoids seemed to have lower intellectual verbal abilities than healthy controls.

The Center for Integrated Molecular Brain Imaging (Cimbi) database

We here describe a multimodality neuroimaging containing data from healthy volunteers and patients, acquired within the Lundbeck Foundation Center for Integrated Molecular Brain Imaging (Cimbi) in Copenhagen, Denmark. The data is of particular relevance for neurobiological research questions related to the serotonergic transmitter system with its normative data on the serotonergic subtype receptors 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT4 and the 5-HT transporter (5-HTT), but can easily serve other purposes. The Cimbi database and Cimbi biobank were formally established in 2008 with the purpose to store the wealth of Cimbi-acquired data in a highly structured and standardized manner in accordance with the regulations issued by the Danish Data Protection Agency as well as to provide a quality-controlled resource for future hypothesis-generating and hypothesis-driven studies. The Cimbi database currently comprises a total of 1100 PET and 1000 structural and functional MRI scans and it holds a multitude of additional data, such as genetic and biochemical data, and scores from 17 self-reported questionnaires and from 11 neuropsychological paper/computer tests. The database associated Cimbi biobank currently contains blood and in some instances saliva samples from about 500 healthy volunteers and 300 patients with e.g., major depression, dementia, substance abuse, obesity, and impulsive aggression. Data continue to be added to the Cimbi database and biobank.

Prefrontal serotonin transporter availability is positively associated with the cortisol awakening response

Stress sensitivity and serotonergic neurotransmission interact, e.g. individuals carrying the low-expressing variants (S and LG) of the 5-HTTLPR promoter polymorphism of the serotonin transporter (SERT) gene are at higher risk for developing mood disorders when exposed to severe stress and display higher cortisol responses when exposed to psychosocial stressors relative to high expressing 5-HTTLPR variants. However, it is not clear how the relation between SERT and cortisol output is reflected in the adult brain. We investigated the relation between cortisol response to awakening (CAR) and SERT binding in brain regions considered relevant to modify the cortisol awakening response.

METHODS

thirty-two healthy volunteers underwent in vivo SERT imaging with [(11)C]DASB-Positron Emission Tomography (PET), genotyping, and performed home-sampling of saliva to assess CAR.

RESULTS

CAR, defined as the area under curve with respect to increase from baseline, was positively coupled to prefrontal SERT binding (p=0.02), independent of adjustment for 5-HTTLPR genotype. Although S- and LG-allele carriers tended to show a larger CAR (p=0.07) than LA homozygous, 5-HTTLPR genotype did not modify the coupling between CAR and prefrontal SERT binding as tested by an interaction analysis (genotype×CAR).

CONCLUSION

prefrontal SERT binding is positively associated with cortisol response to awakening. We speculate that in mentally healthy individuals prefrontal serotonergic neurotransmission may exert an inhibitory control on the cortisol awakening response.

Sustained attention is associated with right superior longitudinal fasciculus and superior parietal white matter microstructure in children

Sustained attention develops during childhood and has been linked to the right fronto-parietal cortices in functional imaging studies; however, less is known about its relation to white matter (WM) characteristics. Here we investigated whether the microstructure of the WM underlying and connecting the right fronto-parietal cortices was associated with sustained attention performance in a group of 76 typically developing children aged 7-13 years. Sustained attention was assessed using a rapid visual information processing paradigm. The two behavioral measures of interest were the sensitivity index d' and the coefficient of variation in reaction times (RTCV ). Diffusion-weighted imaging was performed. Mean fractional anisotropy (FA) was extracted from the WM underlying right dorsolateral prefrontal (DLPFC) and parietal cortex (PC), and the right superior longitudinal fasciculus (SLF), as well as equivalent anatomical regions-of-interest (ROIs) in the left hemisphere and mean global WM FA. When analyzed collectively, right hemisphere ROIs FA was significantly associated with d' independently of age. Follow-up analyses revealed that only FA of right SLF and the superior part of the right PC contributed significantly to this association. RTCV was significantly associated with right superior PC FA, but not with right SLF FA. Observed associations remained significant after controlling for FA of equivalent left hemisphere ROIs or global mean FA. In conclusion, better sustained attention performance was associated with higher FA of WM in regions connecting right frontal and parietal cortices. Further studies are needed to clarify to which extent these associations are driven by maturational processes, stable characteristics and/or experience.

Cortisol awakening response and negative emotionality linked to asymmetry in major limbic fibre bundle architecture

The limbic system plays an important role in regulating the hypothalamic-pituitary-adrenal (HPA) axis as well as aspects of emotion, and both neuroendocrine disturbance and increased negative emotionality are associated with risk for developing affective disorders. However, the extent to which the architecture of connections between limbic structures may be linked to individual differences in basal HPA-axis reactivity and negative emotionality is unknown. Here we tested the hypotheses that microstructural asymmetry of the major limbic fibre bundles would be associated with cortisol awakening response (CAR) and neuroticism, a personality trait associated with the tendency to experience negative emotions. Sixty-nine healthy adults were studied with diffusion-weighted imaging, and fractional anisotropy (FA) was extracted from the cingulum and uncinate fasciculus. Higher neuroticism scores, which were associated with higher CAR, were also correlated with higher right relative to left cingulum FA. Elevated CAR was associated with the degree of FA asymmetry within both the cingulum and the uncinate fasciculus, but in opposing directions. These results suggest that the balance between left- and right-sided limbic circuits may bear an important relationship to hypothalamic-pituitary-adrenal axis reactivity, and to the tendency to experience negative emotions, and they raise important questions about the significance of limbic system architecture.

Brain microstructural correlates of visuospatial choice reaction time in children

The corticospinal tracts and the basal ganglia continue to develop during childhood and adolescence, and indices of their maturation can be obtained using diffusion-weighted imaging. Here we show that a simple measure of visuomotor function is correlated with diffusion parameters in the corticospinal tracts and neostriatum. In a cohort of 75 typically-developing children aged 7 to 13years, mean 5-choice reaction times (RTs) were assessed. We hypothesised that children with faster choice RTs would show lower mean diffusivity (MD) in the corticospinal tracts and neostriatum and higher fractional anisotropy (FA) in the corticospinal tracts, after controlling for age, gender, and handedness. Mean MD and/or FA were extracted from the right and left corticospinal tracts, putamen, and caudate nuclei. As predicted, faster 5-choice RTs were associated with lower MD in the corticospinal tracts, putamen, and caudate. MD effects on RT were bilateral in the corticospinal tracts and putamen, whilst right caudate MD was more strongly related to performance than was left caudate MD. Our results suggest a link between motor performance variability in children and diffusivity in the motor system, which may be related to: individual differences in the phase of fibre tract and neostriatal maturation in children of similar age, individual differences in motor experience during childhood (i.e., use-dependent plasticity), and/or more stable individual differences in the architecture of the motor system.

Postnatal brain development: structural imaging of dynamic neurodevelopmental processes

After birth, there is striking biological and functional development of the brain's fiber tracts as well as remodeling of cortical and subcortical structures. Behavioral development in children involves a complex and dynamic set of genetically guided processes by which neural structures interact constantly with the environment. This is a protracted process, beginning in the third week of gestation and continuing into early adulthood. Reviewed here are studies using structural imaging techniques, with a special focus on diffusion weighted imaging, describing age-related brain maturational changes in children and adolescents, as well as studies that link these changes to behavioral differences. Finally, we discuss evidence for effects on the brain of several factors that may play a role in mediating these brain-behavior associations in children, including genetic variation, behavioral interventions, and hormonal variation associated with puberty. At present longitudinal studies are few, and we do not yet know how variability in individual trajectories of biological development in specific neural systems map onto similar variability in behavioral trajectories.

White matter microstructure in superior longitudinal fasciculus associated with spatial working memory performance in children

During childhood and adolescence, ongoing white matter maturation in the fronto-parietal cortices and connecting fiber tracts is measurable with diffusion-weighted imaging. Important questions remain, however, about the links between these changes and developing cognitive functions. Spatial working memory (SWM) performance improves significantly throughout the childhood years, and several lines of evidence implicate the left fronto-parietal cortices and connecting fiber tracts in SWM processing. Here we report results from a study of 76 typically developing children, 7 to 13 years of age. We hypothesized that better SWM performance would be associated with increased fractional anisotropy (FA) in a left fronto-parietal network composed of the superior longitudinal fasciculus (SLF), the regional white matter underlying the dorsolateral pFC, and the posterior parietal cortex. As hypothesized, we observed a significant association between higher FA in the left fronto-parietal network and better SWM skills, and the effect was independent of age. This association was mainly accounted for by variability in left SLF FA and remained significant when FA measures from global fiber tracts or right SLF were included in the model. Further, the effect of FA in left SLF appeared to be mediated primarily by decreasing perpendicular diffusivity. Such associations could be related to individual differences among children in the architecture of fronto-parietal connections and/or to differences in the pace of fiber tract development. Further studies are needed to determine the contributions of intrinsic and experiential factors to the development of functionally significant individual differences in fiber tract structure.

Effect of paramagnetic manganese cations on (1)H MRS of the brain

Manganese cations (Mn(2+)) can be used as an intracellular contrast agent for structural, functional and neural pathway imaging applications. However, at high concentrations, Mn(2+) is neurotoxic and may influence the concentration of (1)H MR-detectable metabolites. Furthermore, the paramagnetic Mn(2+) cations may also influence the relaxation of the metabolites under investigation. Consequently, the purpose of this study was to investigate the effect of paramagnetic Mn(2+) cations on (1)H-MR spectra of the brain using in vivo and phantom models at 4.7 T. To investigate the direct paramagnetic effects of Mn(2+) cations on the relaxation of N-acetylaspartate (NAA), creatine and choline, T(1) relaxation times of metabolite solutions, with and without 5% albumin, and containing different Mn(2+) concentrations were determined. Relaxivity values with/without 5% albumin for NAA (4.8/28.1 s(-1) mM(-1)), creatine (2.8/2.8 s(-1) mM(-1)) and choline (1.8/1.1 s(-1) mM(-1)) showed NAA to be the most sensitive metabolite to the relaxation effects of the cations. Using an in vivo optic tract tracing imaging model, we obtained two adjacent regions of interest in the superior colliculi with different water T(1) values (Mn(2+)-enhanced = 1.01 s; unenhanced = 1.14 s) 24 h after intravitreal injection of 3 microL 50 mM MnCl(2). Using phantom and in vivo water relaxation time data, we estimated the in vivo Mn(2+) concentration to be 2-8 microM. The phantom data suggest that limited metabolite relaxation effects would be expected at this concentration. Consequently, this study indicates that, in this model, the presence of Mn(2+) cations does not significantly affect (1)H-MR spectra despite possible toxic and paramagnetic effects.

Erythropoietin improves place learning in an 8-arm radial maze in fimbria-fornix transected rats

Systemically administered human recombinant erythropoietin (EPO) may have the potential to reduce the cognitive and behavioral symptoms of mechanical brain injury. In a series of studies, we address this possibility. We previously found that EPO given to fimbriafornix transected rats at the moment of injury could substantially improve the posttraumatic acquisition of an allocentric place learning task when such a task is administered in a water maze. Due to the clinical importance of such results, it is important to scrutinize whether the therapeutic effect of EPO is specific to the experimental setup of our original experiments or generalizes across test situations. Consequently, here we studied the effects of similarly administered EPO in fimbria-fornix transected and control operated rats, respectively, evaluating the posttraumatic behavioral/cognitive abilities in an allocentric place learning task administered in an 8-arm radial maze. The administration of EPO to the hippocampally injured rats was associated with a virtually complete elimination of the otherwise severe behavioral impairment caused by fimbria-fornix transection. In contrast, EPO had no detectable effect on the task acquisition of non-lesioned animals. The results of the present study confirm our previous demonstration of EPO's ability to reduce or eliminate the behavioral/cognitive consequences of mechanical injury to the hippocampus, while adding the important observation that such a therapeutic effect is not restricted to the specific experimental setup previously studied.

Three days of pivmecillinam or norfloxacin for treatment of acute uncomplicated urinary infection in women

Pivmecillinam is a unique beta-lactam antimicrobial that has been used for the treatment of acute uncomplicated urinary infection for > 20 y. Since this agent was introduced, the quinolone antimicrobials have become widely used for the same indication. This study compared the efficacy of a 3-d regimen of pivmecillinam 400 mg b.i.d. with norfloxacin 400 mg b.i.d. Women aged between 18 and 65 y presenting with symptoms of acute cystitis of < 7 d duration were eligible for enrollment; 483 were randomized to receive pivmecillinam and 471 to receive norfloxacin. In each group, 30% of women had negative urine cultures prior to therapy. Bacteriologic cure at early post-therapy follow-up was achieved in 222/298 (75%) pivmecillinam patients and 276/302 (91%) norfloxacin patients [p < 0.001; 95% confidence interval (CI) 12.0-21.8]. Clinical cure/improvement at Day 4 following initiation of therapy was observed in 434/457 (95%) women who received pivmecillinam and 425/442 (96%) who received norfloxacin (p = 0.39; 95% CI 1.5-3.9). Early post-therapy (11 +/- 2 d) clinical cure was achieved in 360/437 women (82%) who received pivmecillinam and 381/433 (88%) who received norfloxacin (p = 0.019; 95% CI 0.9-10.3). In women aged < or = 50 y, early clinical cure rates were 294/351 (84%) for pivmecillinam and 299/340 (88%) for norfloxacin (p = 0.11; 95% CI 1.0-9.4). Adverse effects were similar for both regimens, and there was no evidence of the emergence of organisms of increasing resistance with therapy. Short-course therapy with norfloxacin was superior to that with pivmecillinam in terms of bacteriologic outcome, although differences in clinical outcome were less marked. In conclusion, short-course therapy with pivmecillinam is an effective empirical treatment for pre-menopausal women.

Clinical mastitis in cows treated with sometribove (recombinant bovine somatotropin) and its relationship to milk yield

Effect of sometribove (methionyl bovine somatotropin) on mastitis in 15 full lactation trials (914 cows) in Europe and the US and 70 short-term studies (2697 cows) in eight countries was investigated. In full lactation studies, sometribove (500 mg/2 wk) was given for 252 d, commencing 60 d postpartum. Although herds varied considerably, incidence of clinical mastitis within a herd was similar for cows receiving control and sometribove treatments. Relative risk analyses indicated no treatment effect, and percentage of mastitis during treatment was similar for control and sometribove groups. A positive linear relationship existed between peak milk yield and mastitis incidence (percentage of cows contracting mastitis or cases per 100 cow days); sometribove treatment did not alter this relationship. Increases in mastitis related to milk yield increase from sometribove or related to genetic selection were similar. When expressed per unit of milk, mastitis incidence declined slightly as milk yield increased; this relationship was not altered by sometribove. No effect on clinical mastitis was observed in 70 commercial herds utilizing sometribove for 84 d. However, effects were significant for stage of lactation and milk yield. Overall, studies represented a wide range of research and commercial situations demonstrating that sometribove had no effect on incidence of clinical mastitis during the lactation of treatment. Furthermore, sometribove did not alter typical relationships between milk yield or herd factors and incidence of clinical mastitis.

Factors affecting response of cows to biweekly injections of sometribove

Seventy-eight lactating Holstein cows (18 primiparous and 60 multiparous) were used to study certain factors affecting response in milk yields to biweekly injections of bST. Cows were intramuscularly injected with placebo or with 500 mg of bST every 14 d for 36 wk beginning 60 d postpartum. Primiparous cows responded less to bST than did multiparous cows. Cows were separated into three yield groups within each treatment based on pretreatment yield: low (27.0 kg/d), medium (32.0 kg/d), and high (39.0 kg/d). Response of low yielding cows to bST was numerically greater than that of medium or high yielding cows, but there was no significant interaction between treatment and pretreatment milk yield. Individual cow index for milk yield was used as a measure of genetic potential of cows, which were divided into two index groups: high cow index (greater than -23 kg) and low cow index (less than -23 kg). Cows in the high index group showed significantly higher milk yields than the low index group during treatment, but treatment by cow index interaction was not significant, suggesting that cows of widely ranging genetic potential respond similarly to bST. Response of cows to bST in mid to late lactation was slightly greater than in early lactation (15.9 and 10.6% vs. 17.8%, respectively), but no significant interaction of treatment by days postpartum was noted. Finally, even though cows treated with bST exhibited slightly higher rectal temperatures during the hot summer months, no significant difference in milk yield response to bST was noted during periods of moderate versus high ambient temperatures.

Response of dairy cows to high doses of a sustained-release bovine somatotropin administered during two lactations. 2. Health and reproduction

Eighty-two lactating Holstein cows in their first, second, or third lactation received either one, three, or five concurrent i.m. injections of a unit dose (.6 g) of zinc methionyl bST (sometribove) or five doses of the vehicle. Injections were given at 14-d intervals from 60 +/- 3 d postpartum until the end of lactation or necropsy. Thirty-eight animals were continued on treatment for a 2nd yr. Sometribove did not affect the incidence of ketosis, milk fever, tetany, or pneumonia. Digestive disorders, primarily cows going off feed, were increased by bST during yr 1 only. The incidence of lameness was increased by bST in some time frames because of an increase in the 3.0-g bST group. Lameness was not associated with treatment-specific histopathologic changes or with abnormalities in cartilage or bone. Reproductive health generally was unaffected by treatment, but delayed conception and increased incidence of abortion were noted. Incidence of cystic ovaries was unaffected by bST. Pregnancy rates were decreased during the 100-d breeding interval of yr 1 but not during the 215-d interval of yr 2. The incidence of clinical mastitis was increased by bST, primarily at the 3.0-g dose. During the 2-yr study, 0, 3, 3, and 2 cows died or became moribund on 0, .6, 1.8, and 3.0 g of bST, respectively. Health issues identified for further evaluation included lameness and clinical mastitis for the 3.0-g group and early removal from the herd and decreased reproductive performance for all bST groups. Bovine somatotropin caused no treatment-specific toxic effects in dairy cows even at 3.0 g every 14 d.

Effect of recombinantly-derived bovine somatotropin on reproductive performance of dairy cattle

Data from 814 cows involved in five separate full lactation studies were used to assess the effect of recombinantly-derived methionyl bovine somatotropin (sometribove) on reproductive performance. Data were separated by parity (first and second or greater), route of administration (intramuscular: i.m. or subcutaneous: s.c.), length of breeding period (number of days in milk), and level of production (high vs low). Through 305 days in milk, pregnancy rates were reduced 18% in primiparous, sometribove-treated (i.m.) cows but were not significantly affected in multiparous cows. No differences were noted in either parity group when sometribove was administered subcutaneously. The level of production was more often found to be a significant factor affecting reproductive parameters than was sometribove administration. In general, length of the breeding period and level of milk production had a greater influence on reproductive performance than treatment with sometribove.

Factors affecting insulin-like growth factor-I concentration in bovine milk

To establish the naturally occurring range of insulin-like growth factor-I concentrations in bovine milk, samples from individual cows (n = 409) managed on five Missouri dairy herds were assayed. Parity, stage of lactation, and farm affected milk insulin-like growth factor-I concentration. Milk insulin-like growth factor-I concentration was higher in early lactation than mid and late lactation with concentrations in multiparous cows exceeding those in primiparous cows. Insulin-like growth factor-I concentration was negatively correlated to milk production the day of sample collection (r = -.15) and not correlated to predicted 305-d milk yields. Unprocessed bulk tank milk samples (n = 100) from a commercial processing plant had a mean concentration of insulin-like growth factor-I in milk of 4.32 ng/ml with a range of 1.27 to 8.10 ng/ml. This distribution was similar to the range detected in samples from individual cows, but values were lower than those reported for human milk. Concentration of insulin-like growth factor-I in milk was not altered by pasteurization (at 79 degrees C for 45 s). However, insulin-like growth factor-I was undetectable in milk heated to temperatures (121 degrees C for 5 min) required for infant formula preparation or in commercially available infant formula. These data indicated that insulin-like growth factor-I is a normal but quantitatively variable component of bovine milk that is not destroyed by pasteurization but is undetectable in infant formula. Concentration of insulin-like growth factor-I in bovine milk is lower than concentrations reported for human milk yet similar to those reported for human saliva.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of sometribove in a prolonged-release system in lactating dairy cows--production responses

Primiparous (n = 105) and multiparous (n = 136) Holstein cows were used to evaluate efficacy of sometribove (n-methionyl bovine somatotropin, bST) in a dose titration study. Cows were fed TMR for ad libitum intake, were milked twice daily, and were allocated randomly within parity (1 vs. 2+) to treatments of 0, 250, 500, or 750 mg bST/14 d in a prolonged-release formulation. Subcutaneous injections commenced 60 +/- 3 d postpartum and continued throughout lactation. During a standardized treatment period of 252 d, treatment with increasing dosages of bST increased 3.5% FCM yield in a dose-dependent manner for both primiparous (2.5 kg/d, 10.2%; 3.5 kg/d, 14.3%; and 5.9 kg/d, 24.1%) and multiparous cows (3.1 kg/d, 12.1%; 3.9 kg/d, 15.2%; and 6.8 kg/d, 26.5%). Milk content of fat, protein, lactose, ash, Ca and P, and SCC were not affected by treatment. Over the 252-d treatment period, voluntary intake of energy was increased in bST-treated cows such that BW gain, body condition score, and net energy balance did not differ among treatment groups. Productive efficiency (milk per unit NEL intake corrected for BW change) over the treatment period was significantly increased in a dose-dependent manner for multiparous cows (4.1, 6.8, and 11.0%). Results demonstrated that bST administered in a prolonged-release formulation was efficacious in enhancing milk production and feed efficiency.

Responses by lactating cows in commercial dairy herds to recombinant bovine somatotropin

Cows (890) in 15 US herds were assigned randomly in equal numbers to control or bST injections (500 mg in a prolonged-release form every 14 d for 12 wk) within three stages of lactation (57 to 100, 101 to 140, and 141 to 189 d postpartum) and two parity groups (primiparous and multiparous). Yield and milk composition were monitored 1 d/wk for 16 wk including 2 wk pretreatment and 2 wk posttreatment. Increases in milk and FCM due to bST injections were less at 57 to 100 d than at 101 to 189 d postpartum (milk 3.6 vs. 5.5; FCM 3.9 vs. 6.1 kg/d per cow), and increases in milk and FCM were more for multiparous than for primiparous cows (milk 5.5 vs. 4.2; FCM 6.0 vs. 4.7 kg/d cow). Temporarily, concentration of milk fat increased and protein decreased; later, concentrations for control and injected cows were similar. Postinjection milk fat concentration decreased, but milk protein concentration increased temporarily. The net increase in milk (and FCM) varied significantly among herds from 2.9 to 7.6 kg/d per cow (mean, 4.9 kg). Responses in FCM were similar over a wide range of pretreatment yields. A great variety of feed ingredients were fed as total mixed rations, and nutrient concentrations varied greatly. The SCC were similar before, during, and after treatment, but increase in FCM of injected cows exhibited a negative correlation with pretreatment SCC. Changes in body condition score of sometribove-injected cows varied among herds (.25 to -.45) and averaged -.02 compared with .07 for controls. There was no pattern in incidence of mastitis during sometribove injections.

Effects of recombinant methionyl bovine somatotropin (sometribove) in high producing cows milked three times daily

Effects of daily sometribove administration on milk yield and composition, body condition score, BW, and SCC were evaluated in Holstein cows milked three times daily. Lactating cows (n =104) were assigned randomly to control or sometribove-treated (25 mg/d) groups. The experimental period was 16 wk, consisting of 2-wk pretreatment, 12-wk treatment, and 2-wk posttreatment periods. All cows were injected once daily starting at 53 to 180 d postpartum, housed in free stalls, and fed one of five total mixed rations according to milk production. Body weights were measured weekly, and body condition was scored biweekly. Milk yield was recorded daily, and weekly milk samples were analyzed for fat, protein, lactose, total solids, and SCC. Milk yield and milk protein were increased 18.8% (38.6 vs. 32.5 kg/d) and 3.3% (3.1 vs. 3.0%), respectively, whereas percentage of milk fat, lactose, SNF, SCC, and BW were unaffected by treatment. Overall average body condition scores were lower for the sometribove-treated group versus control (2.2 vs. 2.4). No apparent differences in the number of cows treated for mastitis, foot rot, displaced abomasum, or lameness were observed between treatment groups. Sometribove treatment significantly enhanced milk yield (6.1 kg/d) with no apparent negative effects on health in high producing cows milked three times per day.

The use of an extended baseline period in the evaluation of treatment in a longitudinal Duchenne muscular dystrophy trial

A trial of Duchenne muscular dystrophy involved tracking boys of all ages through a one-year baseline period, followed by a one-year trial of leucine versus placebo treatment. In this paper we develop a model for a total-muscle-strength score that uses the data of the extended baseline period in the evaluation of the leucine treatment. The model is based on a polynomial growth curve in age whose coefficients can vary according to treatment or phase. Maximum likelihood estimates of the parameters of the model are obtained from use of the EM algorithm. We propose tests for the adequacy of the model as well as for treatment effects. A quadratic model appears the most parsimonious fit to the data and there is no evidence of any leucine effect on scores. We examine the asymptotic power of the test for treatment effect and compare it with that of a simpler analysis.