Exhaustion disorder and altered brain activity in frontal cortex detected with fNIRS.

Patients with stress-related Exhaustion Disorder (ED) have problems with memory and executive function. These problems have been associated with deviant activity in prefrontal cortex (PFC). We investigated cognitive performance and functional activity in the PFC during prolonged mental activity in patients with ED (n = 20, 16 women) with a mean duration since diagnosis of 46 ± 23 months in comparison to healthy individuals (n = 20, 12 women). A block of six neuropsychological tests was performed in a sequence that was repeated once. The brain imaging technique, functional near infrared spectroscopy (fNIRS) was used for all tests. There were no differences between the groups in terms of changes over time, i.e. difference between first and second test block. In the Stroop-Simon test, the controls showedhigher functional activity in the frontal cortex. In the left ventrolateral PFC, we observed an increased activity in controls in the incongruent compared to the congruent trials, whereas no changes were detected in the ED patient group. During processing speed tasks, only ED patients showed higher functional activity in right dorsolateral PFC. The ED patients reported lower subjective energy level and they also performed less well on a mental control task compared to healthy individuals. In conclusion, ED patients showed altered functional activity compared to controls, indicating that ED patients process information differently in the prefrontal cortex, but the functional activity did not change during the 2½ hr procedure, as revealed by the test-retest design. Lay summary In this paper we show that patient with exhaustion disorder have a reduced functional activity in the prefrontal cortex. This functional activity was not affected by 2.5 hours mental activity.

Anxiety severity and cognitive function in primary care patients with anxiety disorder: a cross-sectional study.

BACKGROUND: Deficits in cognitive performance are reported in patients with anxiety disorders, but research is limited and inconsistent. We aimed to investigate cross-sectional associations between cognitive function, with focus on executive function, and anxiety severity in primary care patients diagnosed with anxiety disorders. METHODS: 189 Swedish patients aged 18-65 years (31% men) with anxiety disorders diagnosed according to Mini International Neuropsychiatric Interview were included. Severity of anxiety was assessed using Beck Anxiety Inventory self-assessment scale. Digit span, block design and matrix reasoning tests from the Wechsler Adult Intelligence Scale IV, and the design fluency test from the Delis-Kaplan Executive Function System were used. Multivariable linear regression models were applied to investigate the relationship of anxiety severity and cognitive functioning. Comparisons were also performed to a normed non-clinical population, using the Wilcoxon signed rank test. RESULTS: More severe anxiety was associated with lower digit span test scores (R2 = 0.109, B = -0.040, p = 0.018), but not with block design, matrix reasoning or design fluency tests scores, after adjustment for comorbid major depression in a multivariable model. When compared to a normed population, patients with anxiety performed significantly lower on the block design, digit span forward, digit span sequencing and matrix reasoning tests. CONCLUSIONS: Severity of anxiety among patients with anxiety disorder was associated with executive functions related to working memory, independently of comorbid major depression, but not with lower fluid intelligence. A further understanding of the executive behavioral control in patients with anxiety could allow for more tailored treatment strategies including medication, therapy and interventions targeted to improve specific cognitive domains.

Late-adolescent risk factors for suicide and self-harm in middle-aged men: explorative prospective population-based study.

BACKGROUND: Recent reports show alarmingly high rates of suicide in middle-aged men, yet there are few long-term prospective studies that focus on suicidal behaviour in men in this age group. AIMS: To prospectively explore associations of potential risk factors at age 18 with suicide and self-harm in middle-aged men. METHOD: A population-based Swedish longitudinal cohort study of male conscripts with no history of self-harm at enlistment in 1968-1989 (n = 987 583). Conscription examinations included measures of cognitive performance, stress resilience, psychiatric diagnoses, body mass index (BMI), cardiovascular fitness and muscle strength. Suicides and self-harm at age 45-65 years were identified in the National Hospital Register and Swedish Cause of Death Register. Risks were calculated using Cox proportional hazards models. RESULTS: Low stress resilience (cause-specific hazard ratio CHR = 2.31, 95% CI 1.95-2.74), low cognitive ability (CHR = 2.01, 95% CI 1.71-2.37) as well as psychiatric disorders and low cardiovascular fitness in late adolescence were associated with increased risk for suicide in middle-aged men. Similar risk estimates were obtained for self-harm. In addition, high and low BMI as well as low muscle strength were associated with increased risk of self-harm. Associations also remained significant after exclusion of men with self-harm before age 45. CONCLUSIONS: This prospective study provides life-course perspective support that psychological and physical characteristics in late adolescence may have long-lasting consequences for suicidal behaviour in middle-aged men, a very large population at heightened risk of suicide.

Enriched, Task-Specific Therapy in the Chronic Phase After Stroke: An Exploratory Study.

BACKGROUND AND PURPOSE: There is a need to translate promising basic research about environmental enrichment to clinical stroke settings. The aim of this study was to assess the effectiveness of enriched, task-specific therapy in individuals with chronic stroke. METHODS: This is an exploratory study with a within-subject, repeated-measures design. The intervention was preceded by a baseline period to determine the stability of the outcome measures. Forty-one participants were enrolled at a mean of 36 months poststroke. The 3-week intervention combined physical therapy with social and cognitive stimulation inherent to environmental enrichment. The primary outcome was motor recovery measured by Modified Motor Assessment Scale (M-MAS). Secondary outcomes included balance, walking, distance walked in 6 minutes, grip strength, dexterity, and multiple dimensions of health. Assessments were made at baseline, immediately before and after the intervention, and at 3 and 6 months. RESULTS: The baseline measures were stable. The 39 participants (95%) who completed the intervention had increases of 2.3 points in the M-MAS UAS and 5 points on the Berg Balance Scale (both P < 0.001; SRM >0.90), an improvement of comfortable and fast gait speed of 0.13 and 0.23 m/s, respectively. (P < 0.001; SRM = 0.88), an increased distance walked over 6 minutes (24.2 m; P < 0.001; SRM = 0.64), and significant improvements in multiple dimensions of health. The improvements were sustained at 6 months. DISCUSSION AND CONCLUSIONS: Enriched, task-specific therapy may provide durable benefits across a wide spectrum of motor deficits and impairments after stroke. Although the results must be interpreted cautiously, the findings have implications for enriching strategies in stroke rehabilitation.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A304).

Adult Hippocampal Neurogenesis: A Coming-of-Age Story.

What has become standard textbook knowledge over the last decade was a hotly debated matter a decade earlier: the proposition that new neurons are generated in the adult mammalian CNS. The early discovery by Altman and colleagues in the 1960s was vulnerable to criticism due to the lack of technical strategies for unequivocal demonstration, quantification, and physiological analysis of newly generated neurons in adult brain tissue. After several technological advancements had been made in the field, we published a paper in 1996 describing the generation of new neurons in the adult rat brain and the decline of hippocampal neurogenesis during aging. The paper coincided with the publication of several other studies that together established neurogenesis as a cellular mechanism in the adult mammalian brain. In this Progressions article, which is by no means a comprehensive review, we recount our personal view of the initial setting that led to our study and we discuss some of its implications and developments that followed. We also address questions that remain regarding the regulation and function of neurogenesis in the adult mammalian brain, in particular the existence of neurogenesis in the adult human brain.

Effects of exercise on symptoms of anxiety, cognitive ability and sick leave in patients with anxiety disorders in primary care: study protocol for PHYSBI, a randomized controlled trial.

BACKGROUND: Anxiety disorders are common and associated with reduced quality of life, impaired physical and mental health and an increased economic burden for society. While evidence exists for the effectiveness of exercise treatment for depression, there is a need for high-quality randomized clinical trials (RCT) with a focus on anxiety disorders. Further research is also warranted regarding outcomes of cognitive function, other health-related variables, dose-response effects, work ability and potential mechanisms. METHOD/DESIGN: Using a parallel, RCT design with three assessment points (baseline, post-intervention and one-year follow-up), we aim to assess the effect of a 12-week exercise intervention in primary care patients with anxiety disorders (n = 180), diagnosed using the Mini International Neuropsychiatric Interview (M.I.N.I; Swedish version 6.0.0d DSM-IV). Participants are randomly assigned to three physical exercise groups: one low-intensity training group, one moderate- to high intensity training group and one control non-exercise group. Assessments include measures of anxiety symptoms, cognitive function, physical health variables such as cardiovascular fitness, sick-leave and levels of hormones/cytokines in blood samples. DISCUSSION: Findings from this study will provide novel insights regarding the effects of exercise treatment on not only anxiety symptoms but also other outcomes including mental and physical health, cognitive function, dose-response effects, work ability/sick leave and on biomarkers that may help explain underlying mechanisms. TRIAL REGISTRATION: The trial was registered at ClinicalTrial.gov NCT03247270 August 8, 2017.

Altered levels of circulating insulin-like growth factor I (IGF-I) following ischemic stroke are associated with outcome - a prospective observational study.

BACKGROUND: Insulin-like growth factor I (IGF-I) has neuroprotective effects in experimental ischemic stroke (IS). However, in patients who have suffered IS, various associations between the levels of serum IGF-I (s-IGF-I) and clinical outcome have been reported, probably reflecting differences in sampling time-points and follow-up periods. Since changes in the levels of post-stroke s-IGF-I have not been extensively explored, we investigated whether decreases in the levels of s-IGF-I between the acute time-point (median, 4 days) and 3 months (ΔIGF-I, further transformed into ΔIGF-I-quintiles, ΔIGF-I-q) are associated with IS severity and outcome. METHODS: In the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS) conducted in Gothenburg, Sweden, patients with IS who had s-IGF-I measurements available were included (N = 354; 65% males; mean age, 55 years). Baseline stroke severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS) and converted into NIHSS-quintiles (NIHSS-q). Outcomes were assessed using the modified Rankin Scale (mRS) at 3 months and 2 years. RESULTS: In general, the levels of s-IGF-I decreased (positive ΔIGF-I), except for those patients with the most severe NIHSS-q. After correction for sex and age, the 3rd ΔIGF-I-q showed the strongest association to mRS 0-2 [Odds Ratio (OR) 5.11, 95% confidence interval (CI) 2.18-11.9], and after 2 years, the 5th ΔIGF-I-q (OR 3.63, 95% CI 1.40-9.38) showed the strongest association to mRS 0-2. The associations remained significant after multivariate correction for diabetes, smoking, hypertension, and hyperlipidemia after 3 months, but were not significant (p = 0.057) after 2 years. The 3-month associations withstood additional correction for baseline stroke severity (p = 0.035), whereas the 2-year associations were further attenuated (p = 0.31). CONCLUSIONS: Changes in the levels of s-IGF-I are associated primarily with temporally near 3-month outcomes, while associations with long-term 2-year outcomes are weakened and attenuated by other factors. The significance of the change in post-stroke s-IGF-I is compatible with a positive role for IGF-I in IS recovery. However, the exact mechanisms are unknown and probably reflects combinations of multiple peripheral and central actions.

Nonpsychotic Mental Disorders in Teenage Males and Risk of Early Stroke: A Population-Based Study.

BACKGROUND AND PURPOSE: Although the incidence of stroke is on the decline worldwide, this is not the case for early stroke. We aimed to determine whether nonpsychotic mental disorder at the age of 18 years is a risk factor for early stroke, and if adolescent cardiovascular fitness and intelligence quotient might attenuate the risk. METHOD: Population-based Swedish cohort study of conscripts (n=1 163 845) who enlisted during 1968 to 2005. At conscription, 45 064 males were diagnosed with nonpsychotic mental disorder. Risk of stroke during follow-up (5-42 years) was calculated with Cox proportional hazards models. Objective baseline measures of fitness and cognition were included in the models in a second set of analyses. RESULTS: There were 7770 first-time stroke events. In adjusted models, increased risk for stroke was observed in men diagnosed with depressive/neurotic disorders (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.11-1.37), personality disorders (HR, 1.52; 95% CI, 1.29-1.78), and alcohol/substance use disorders (HR, 1.61; 95% CI, 1.41-1.83) at conscription. Corresponding figures for fatal stroke were HR, 1.38; 95% CI, 1.06 to 1.79; HR, 2.26; 95% CI, 1.60 to 3.19; and HR, 2.20; 95% CI, 1.63 to 2.96. HRs for stroke were attenuated when fitness level and intelligence quotient were introduced. Associations remained significant for personality disorders and alcohol/substance use in the fully adjusted models. The interaction term was statistically significant for fitness but not for intelligence quotient. CONCLUSIONS: Our findings suggest that fitness may modify associations between nonpsychotic disorders and stroke. It remains to be clarified whether interventions designed to improve fitness in mentally ill youth can influence future risk of early stroke.

Influence of Cardiovascular Fitness and Muscle Strength in Early Adulthood on Long-Term Risk of Stroke in Swedish Men.

BACKGROUND AND PURPOSE: Low cardiovascular fitness (fitness) in mid- and late life is a risk factor for stroke. However, the respective effects on long-term stroke risk of fitness and muscle strength in early adulthood are unknown. Therefore, we analyzed these in a large cohort of young men. METHOD: We performed a population-based longitudinal cohort study of Swedish male conscripts registered in 1968 to 2005. Data on fitness (by the cycle ergometric test; n=1 166 035) and muscle strength (n=1,563,750) were trichotomized (low, medium, and high). During a 42-year follow-up, risk of stroke (subarachnoidal hemorrhage, intracerebral hemorrhage, and ischemic stroke) and fatality were calculated with Cox proportional hazards models. To identify cases, we used the International Classification of Diseases-Eighth to Tenth Revision in the Hospital Discharge Register and the Cause of Death Register. RESULTS: First-time stroke events were identified (subarachnoidal hemorrhage, n=895; intracerebral hemorrhage, n=2904; ischemic stroke, n=7767). For all stroke and fatality analysis any type of first-time stroke was recorded (n=10,917). There were inverse relationships in a dose-response fashion between fitness and muscle strength with any stroke (adjusted hazard ratios for the lowest, compared with the highest, tertile of each 1.70 [1.50-1.93] and 1.39 [1.27-1.53], respectively). There were stronger associations for fatal stroke. All 3 stroke types displayed similar associations. Associations between fitness and stroke remained when adjusted for muscle strength, whereas associations between muscle strength and stroke weakened/disappeared when adjusted for fitness. CONCLUSIONS: At the age of 18 years, low fitness and to a lesser degree low muscle strength were independently associated with an increased future stroke risk.

Cardiovascular and cognitive fitness at age 18 and risk of early-onset dementia.

Patients with early-onset dementia are a significantly under-recognized subgroup of patients with an increasing prevalence. Epidemiological studies are limited and studies of modifiable risk factors, such as physical fitness, are lacking. We aimed to investigate the associations between cardiovascular fitness individually and in combination with cognitive performance at age 18 and risk of early-onset dementia and mild cognitive impairment later in life. We performed a population-based cohort study of over 1.1 million Swedish, 18-year-old, male conscripts, who underwent conscription exams between 1968 and 2005. These males were then followed for up to 42 years. Objective data on cardiovascular fitness and cognitive performance were collected during conscription exams and were subsequently linked with hospital registries to calculate later risk of early-onset dementia and mild cognitive impairment using Cox proportional hazards models controlling for several confounders. The scores from the exams were divided into tertiles (low, medium, high) for the analyses. The mean follow-up time for the analyses was 25.7 years (standard deviation: 9.3) and the median was 27 years. In total, 30 195 315 person-years of follow-up were included in the study. In fully adjusted models, both low cardiovascular fitness and cognitive performance (compared to high) at age 18 were associated with increased risk for future early-onset dementia (cardiovascular fitness, n = 662 events: hazard ratio 2.49, 95%, confidence interval 1.87-3.32; cognitive performance, n = 657 events: hazard ratio 4.11, 95%, confidence interval 3.19-5.29) and mild cognitive impairment (cardiovascular fitness, n = 213 events: hazard ratio 3.57, 95%, confidence interval 2.23-5.74; cognitive performance, n = 212 events: hazard ratio 3.23, 95%, confidence interval 2.12-4.95). Poor performance on both cardiovascular fitness and cognitive tests was associated with a >7-fold (hazard ratio 7.34, 95%, confidence interval 5.08-10.58) and a >8-fold (hazard ratio 8.44, 95%, confidence interval 4.64-15.37) increased risk of early-onset dementia and early-onset mild cognitive impairment, respectively. In conclusion, lower cardiovascular fitness and cognitive performance in early adulthood were associated with an increased risk of early-onset dementia and mild cognitive impairment later in life, and the greatest risks were observed for individuals with a combination of low cardiovascular fitness and low cognitive performance.

Stem cell responses to plasma surface modified electrospun polyurethane scaffolds.

The topographical effects from functional materials on stem cell behavior are currently of interest in tissue engineering and regenerative medicine. Here we investigate the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell (hESC) and rat postnatal neural stem cell (NSC) responses. The plasma gases were found to induce three combinations of fiber surface functionalities and roughness textures. On randomly oriented fibers, plasma treatments lead to substantially increased hESC attachment and proliferation as compared to native fibers. Argon plasma was found to induce the most optimal combination of surface functionality and roughness for cell expansion. Contact guided migration of cells and alignment of cell processes were observed on aligned fibers. Neuronal differentiation around 5% was found for all samples and was not significantly affected by the induced variations of surface functional group distribution or individual fiber topography. FROM THE CLINICAL EDITOR: In this study the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell and rat postnatal neural stem cell (NSC) responses is studied with the goal of clarifying the potential effects of functional materials on stem cell behavior, a topic of substantial interest in tissue engineering and regenerative medicine.

A lifetime perspective on risk factors for cognitive decline with a special focus on early events.

Both Alzheimer's disease and vascular dementia are the result of disease processes that typically develop over several decades. Population studies have estimated that more than half of the risk for dementia is preventable or at least modifiable through behavioral adaptations. The association between these lifestyle factors and the risk of dementia is most evident for exposure in midlife. However, habits formed in middle age often reflect a lifetime of behavior patterns and living conditions. Therefore, individuals who, for example, are able to maintain healthy diets and regular exercise during their middle years are likely to benefit from these cognition-protective habits they have practiced throughout their lives. For numerous adult diseases, significant risks can often be traced back to early childhood. Suboptimal conditions during the perinatal period, childhood and adolescence can increase the risk of adult diseases, including stroke, heart disease, insulin resistance, hypertension and dementia. This review aims at summarizing some of the evidence for dementia risks from a life-time perspective with the goal of raising awareness for early dementia prevention and successful aging.

Running in mice increases the expression of brain hemoglobin-related genes interacting with the GH/IGF-1 system.

The beneficial effects of exercise are partly mediated via local or systemic functions of the insulin-like growth factor-1 (IGF-1) system. As IGF-1 increases local brain hemoglobin beta (Hbb) transcripts, we hypothesized that exercise could have similar effects. Mice were single-housed with free access to running wheels for seven days. After sacrifice and saline perfusion, the expression of 13 genes was quantified using real-time quantitative polymerase chain reaction (RT-qPCR) in three brain regions: the prefrontal cortex, motor cortex, and hippocampus. In addition, plasma insulin, glucose, homeostatic model assessment of IR (HOMA-IR), C-peptide, and IGF-1 were investigated. We show that hemoglobin-related transcripts (Hbb and 5'-aminolevulinate synthase 2 [Alas2]) increased 46-63% in the running group, while IGF-1-related genes [Igf1 / growth hormone receptor (Ghr)] decreased slightly (7%). There were also moderate to large correlations between Hbb- and IGF-1-related genes in the running group but not in the sedentary group. HOMA-IR, plasma glucose, and insulin changed marginally and non-significantly, but there was a trend toward an increase in plasma-IGF-1 in the running group. In conclusion, seven days of running increased Hbb-related transcripts in three brain regions. Hbb-related transcripts correlated with components of the brain IGF-1 system only in the running group.

Brain tissue haemoglobin expression in saline-perfused vs non-perfused rodents.

Haemoglobin beta (Hbb) and delta-aminolevulinate synthase 2 (Alas2) messenger RNA (mRNA) is mainly found in immature red blood cells, reticulocytes, and not in mature erythrocytes. However, these are also expressed in other tissues such as brain cells, mostly neurons. Therefore, exact quantification of neural tissue homogenates may be confounded by remaining blood in the brain vasculature that may give falsely high values of Hbb/Alas2 expression. To investigate and compare the contribution of local Hbb/Alas2 expression, we investigated mRNA expression locally in the hippocampus and prefrontal cortex, in post-sacrifice saline-perfused and non-perfused mice and rats. Although there was a higher level of Hbb/Alas2 transcripts in the non-perfused animals, there was a significant mRNA expression in perfused brains that could at most partially be explained by remaining blood. Finally, we suggest that saline-perfusion should be recommended for quantification of brain Hbb/Alas2 transcripts in homogenates.

Radixin expression in microglia after cortical stroke lesion.

Stroke induces extensive tissue remodeling, resulting in the activation of several cell types in the brain as well as recruitment of blood-borne leucocytes. Radixin is part of a cytoskeleton linker protein family with the ability to connect transmembrane proteins to the actin cytoskeleton, promoting cell functions involving a dynamic cytoskeleton such as morphological changes, cell division and migration which are common events of different cell types after stroke. In the healthy adult brain radixin is expressed in Olig2(+) cells throughout the brain and in neural progenitor cells in the subventricular zone. In the current study, we detected a 2.5 fold increase in the number of radixin positive cells in the peri-infarct cortex two weeks after the induction of cortical stroke by photothrombosis. Similarly, the number of Olig2(+) cells increased in the peri-infarct area after stroke; however, the number of radixin(+)/Olig2(+) cells was unchanged. Neural progenitor cells maintained radixin expression on their route to the infarct. More surprising however, was the expression of radixin in activated microglia in the peri-infarct cortex. Seventy percent of Iba1(+) cells expressed radixin after stroke, a population which was not present in the control brain. Furthermore, activation of radixin was predominantly detected in the peri-infarct region of oligodendrocyte progenitors and microglia. The specific location of radixin(+) cells in the peri-infarct region and in microglia suggests a role for radixin in microglial activation after stroke.

Cardiovascular fitness in males at age 18 and risk of serious depression in adulthood: Swedish prospective population-based study.

BACKGROUND: Studies suggest a role for cardiovascular fitness in the prevention of affective disorders. AIMS: To determine whether cardiovascular fitness at age 18 is associated with future risk of serious affective illness. METHOD: Population-based Swedish cohort study of male conscripts (n = 1 117 292) born in 1950-1987 with no history of mental illness who were followed for 3-40 years. Data on cardiovascular fitness at conscription were linked with national hospital registers to calculate future risk of depression (requiring in-patient care) and bipolar disorder. RESULTS: In fully adjusted models low cardiovascular fitness was associated with increased risk for serious depression (hazard ratios (HR) = 1.96, 95%, CI 1.71-2.23). No such association could be shown for bipolar disorder (HR = 1.11, 95% CI 0.84-1.47). CONCLUSIONS: Lower cardiovascular fitness at age 18 was associated with increased risk of serious depression in adulthood. These results strengthen the theory of a cardiovascular contribution to the aetiology of depression.

Unique gene expression patterns indicate microglial contribution to neural stem cell recovery following irradiation.

Ionizing radiation results in damage to neural stem cells and reduced neurogenesis. The aim of the present study was to determine intrinsic and extrinsic factors that influence neural stem cell survival following irradiation, using qPCR. Gene expression of hippocampal and SVZ neurospheres were analyzed following irradiation, and results demonstrated that irradiated hippocampal and SVZ stem cells displayed similar gene expression profiles for intrinsic genes. Irradiated microglia (extrinsic factor) isolated from the SVZ exhibited increased gene expression of growth factors involved in stem cell maintenance, proliferation, and survival. However, microglial genes in the irradiated hippocampus responded less favorably with respect to stem cell recovery. This might explain the superior recovery of SVZ compared to hippocampal stem cells following in vivo irradiation. In addition, our results show that a combination of growth factors, which were upregulated in SVZ microglia, increased the proliferation and decreased cell death of irradiated neurospheres in vitro.

Cardiovascular fitness is associated with cognition in young adulthood.

During early adulthood, a phase in which the central nervous system displays considerable plasticity and in which important cognitive traits are shaped, the effects of exercise on cognition remain poorly understood. We performed a cohort study of all Swedish men born in 1950 through 1976 who were enlisted for military service at age 18 (N = 1,221,727). Of these, 268,496 were full-sibling pairs, 3,147 twin pairs, and 1,432 monozygotic twin pairs. Physical fitness and intelligence performance data were collected during conscription examinations and linked with other national databases for information on school achievement, socioeconomic status, and sibship. Relationships between cardiovascular fitness and intelligence at age 18 were evaluated by linear models in the total cohort and in subgroups of full-sibling pairs and twin pairs. Cardiovascular fitness, as measured by ergometer cycling, positively associated with intelligence after adjusting for relevant confounders (regression coefficient b = 0.172; 95% CI, 0.168-0.176). Similar results were obtained within monozygotic twin pairs. In contrast, muscle strength was not associated with cognitive performance. Cross-twin cross-trait analyses showed that the associations were primarily explained by individual specific, non-shared environmental influences (> or = 80%), whereas heritability explained < 15% of covariation. Cardiovascular fitness changes between age 15 and 18 y predicted cognitive performance at 18 y. Cox proportional-hazards models showed that cardiovascular fitness at age 18 y predicted educational achievements later in life. These data substantiate that physical exercise could be an important instrument for public health initiatives to optimize educational achievements, cognitive performance, as well as disease prevention at the society level.

Effects of exercise on symptoms of anxiety in primary care patients: A randomized controlled trial.

BACKGROUND: There is a need for high-quality research regarding exercise interventions for persons with anxiety disorders. We investigate whether a 12-week exercise intervention, with different intensities, could reduce anxiety symptoms in patients with anxiety disorders. METHODS: 286 patients were recruited from primary care in Sweden. Severity of symptoms was self-assessed using the Beck Anxiety Inventory (BAI) and the Montgomery Åsberg Depression Rating Scale (MADRS-S). Participants were randomly assigned to one of two group exercise programs with cardiorespiratory and resistance training and one control/standard treatment non-exercise group, with 1:1:1 allocation. RESULTS: Patients in both exercise groups showed larger improvements in both anxiety and depressive symptoms compared to the control group. No differences in effect sizes were found between the two groups. To study a clinically relevant improvement, BAI and MADRS-S were dichotomized with the mean change in the control group as reference. In adjusted models the odds ratio for improved symptoms of anxiety after low-intensity training was 3.62 (CI 1.34-9.76) and after moderate/high intensity 4.88 (CI 1.66-14.39), for depressive symptoms 4.96 (CI 1.81-13.6) and 4.36 (CI 1.57-12.08) respectively. There was a significant intensity trend for improvement in anxiety symptoms. LIMITATIONS: The use of self-rating measures which bears the risk of an under- or overestimation of symptoms. CONCLUSIONS: A 12-week group exercise program proved effective for patients with anxiety syndromes in primary care. These findings strengthen the view of physical exercise as an effective treatment and could be more frequently made available in clinical practice for persons with anxiety issues.

Long-term stimulation of neural progenitor cell migration after cortical ischemia in mice.

BACKGROUND AND PURPOSE: Cortical ischemia induces neural progenitor cell migration toward the injury site; however, whether these cells are capable of maintaining the migratory response for a longer period after injury remains uncertain. METHODS: We analyzed progenitor migration up to 1 year after induction of photothrombotic stroke to the mouse neocortex. Migrating progenitors identified as doublecortin positive cells (DCX+) were assessed using the immunohistochemistry and immunofluorescence. The thymidine analogues chlorodeoxyuridine and iododeoxyuridine were used to birth-date the progenitor cells. RESULTS: In the striatum, we detected elevated numbers of DCX+ cells up to 6 weeks postlesion. In the corpus callosum and the peri-infarct cortex (Ctx), DCX+ cell numbers were increased up to 1 year. The orientation of the migrating progenitors was mostly aligned with the corpus callosum fiber tract at all time points; however, in the Ctx, they aligned parallel to the infarct border. The injured cortex continuously receives new progenitors up to 1 year after lesion. Cells born after lesion did not become mature neurons, although a portion of the migrating progenitors showed initial signs of differentiation into neurons. CONCLUSIONS: Neural progenitors might have a role in brain plasticity after cortical stroke, especially considering the prolonged window of migratory responses of up to 1 year after stroke lesion.