Pupil responses to colorfulness are selectively reduced in healthy older adults.

The alignment between visual pathway signaling and pupil dynamics offers a promising non-invasive method to further illuminate the mechanisms of human color perception. However, only limited research has been done in this area and the effects of healthy aging on pupil responses to the different color components have not been studied yet. Here we aim to address this by modelling the effects of color lightness and chroma (colorfulness) on pupil responses in young and older adults, in a closely controlled passive viewing experiment with 26 broad-spectrum digital color fields. We show that pupil responses to color lightness and chroma are independent from each other in both young and older adults. Pupil responses to color lightness levels are unaffected by healthy aging, when correcting for smaller baseline pupil sizes in older adults. Older adults exhibit weaker pupil responses to chroma increases, predominantly along the Green-Magenta axis, while relatively sparing the Blue-Yellow axis. Our findings complement behavioral studies in providing physiological evidence that colors fade with age, with implications for color-based applications and interventions both in healthy aging and later-life neurodegenerative disorders.

Thinking eyes: visual thinking strategies and the social brain.

The foundation of art processes in the social brain can guide the scientific study of how human beings perceive and interact with their environment. Here, we applied the theoretical frameworks of the social and artistic brain connectomes to an eye-tracking paradigm with the aim to elucidate how different viewing conditions and social cues influence gaze patterns and personal resonance with artworks and complex imagery in healthy adults. We compared two viewing conditions that encourage personal or social perspective taking-modeled on the well-known Visual Thinking Strategies (VTS) method-to a viewing condition during which only contextual information about the image was provided. Our findings showed that the viewing conditions that used VTS techniques directed the gaze more toward highly salient social cues (Animate elements) in artworks and complex imagery, compared to when only contextual information was provided. We furthermore found that audio cues also directed visual attention, whereby listening to a personal reflection by another person (VTS) had a stronger effect than contextual information. However, we found no effect of viewing condition on the personal resonance with the artworks and complex images when taking the random effects of the image selection into account. Our study provides a neurobiological grounding of the VTS method in the social brain, revealing that this pedagogical method of engaging viewers with artworks measurably shapes people's visual exploration patterns. This is not only of relevance to (art) education but also has implications for art-based diagnostic and therapeutic applications.

[Haemorrhagic shock after frenotomy of the lingual and maxillary labial frenula in a neonate]. / Hemorragische shock na frenulotomie bij een neonaat.

Frenotomy of the lingual and maxillary labial frenula in neonates is considered a safe procedure and is increasingly performed globally. However, there is no consistent evidence for the indication and effectiveness of this intervention. In this clinical lesson, we show that frenotomy of the lingual and maxillary labial frenula in neonates is controversial and can have serious complications. We describe a patient that, in addition to pain and the risk of infection, was in a life-threatening haemorrhagic shock after frenotomy of the lingual and maxillary labial frenula. Frenotomy should only be considered after a multi-disciplinary approach of neonates with breastfeeding problems in whom a medical cause is excluded and no contraindications have been identified.

The architecture of abnormal reward behaviour in dementia: multimodal hedonic phenotypes and brain substrate.

Abnormal reward processing is a hallmark of neurodegenerative diseases, most strikingly in frontotemporal dementia. However, the phenotypic repertoire and neuroanatomical substrates of abnormal reward behaviour in these diseases remain incompletely characterized and poorly understood. Here we addressed these issues in a large, intensively phenotyped patient cohort representing all major syndromes of sporadic frontotemporal dementia and Alzheimer's disease. We studied 27 patients with behavioural variant frontotemporal dementia, 58 with primary progressive aphasia (22 semantic variant, 24 non-fluent/agrammatic variant and 12 logopenic) and 34 with typical amnestic Alzheimer's disease, in relation to 42 healthy older individuals. Changes in behavioural responsiveness were assessed for canonical primary rewards (appetite, sweet tooth, sexual activity) and non-primary rewards (music, religion, art, colours), using a semi-structured survey completed by patients' primary caregivers. Changes in more general socio-emotional behaviours were also recorded. We applied multiple correspondence analysis and k-means clustering to map relationships between hedonic domains and extract core factors defining aberrant hedonic phenotypes. Neuroanatomical associations were assessed using voxel-based morphometry of brain MRI images across the combined patient cohort. Altered (increased and/or decreased) reward responsiveness was exhibited by most patients in the behavioural and semantic variants of frontotemporal dementia and around two-thirds of patients in other dementia groups, significantly (P < 0.05) more frequently than in healthy controls. While food-directed changes were most prevalent across the patient cohort, behavioural changes directed toward non-primary rewards occurred significantly more frequently (P < 0.05) in the behavioural and semantic variants of frontotemporal dementia than in other patient groups. Hedonic behavioural changes across the patient cohort were underpinned by two principal factors: a 'gating' factor determining the emergence of altered reward behaviour and a 'modulatory' factor determining how that behaviour is directed. These factors were expressed jointly in a set of four core, trans-diagnostic and multimodal hedonic phenotypes: 'reward-seeking', 'reward-restricted', 'eating-predominant' and 'control-like'-variably represented across the cohort and associated with more pervasive socio-emotional behavioural abnormalities. The principal gating factor was associated (P < 0.05 after correction for multiple voxel-wise comparisons over the whole brain) with a common profile of grey matter atrophy in anterior cingulate, bilateral temporal poles, right middle frontal and fusiform gyri: the cortical circuitry that mediates behavioural salience and semantic and affective appraisal of sensory stimuli. Our findings define a multi-domain phenotypic architecture for aberrant reward behaviours in major dementias, with novel implications for the neurobiological understanding and clinical management of these diseases.

More Than Meets the Eye: Art Engages the Social Brain.

Here we present the viewpoint that art essentially engages the social brain, by demonstrating how art processing maps onto the social brain connectome-the most comprehensive diagram of the neural dynamics that regulate human social cognition to date. We start with a brief history of the rise of neuroaesthetics as the scientific study of art perception and appreciation, in relation to developments in contemporary art practice and theory during the same period. Building further on a growing awareness of the importance of social context in art production and appreciation, we then set out how art engages the social brain and outline candidate components of the "artistic brain connectome." We explain how our functional model for art as a social brain phenomenon may operate when engaging with artworks. We call for closer collaborations between the burgeoning field of neuroaesthetics and arts professionals, cultural institutions and diverse audiences in order to fully delineate and contextualize this model. Complementary to the unquestionable value of art for art's sake, we argue that its neural grounding in the social brain raises important practical implications for mental health, and the care of people living with dementia and other neurological conditions.

Decoding expectation and surprise in dementia: the paradigm of music.

Making predictions about the world and responding appropriately to unexpected events are essential functions of the healthy brain. In neurodegenerative disorders, such as frontotemporal dementia and Alzheimer's disease, impaired processing of 'surprise' may underpin a diverse array of symptoms, particularly abnormalities of social and emotional behaviour, but is challenging to characterize. Here, we addressed this issue using a novel paradigm: music. We studied 62 patients (24 female; aged 53-88) representing major syndromes of frontotemporal dementia (behavioural variant, semantic variant primary progressive aphasia, non-fluent-agrammatic variant primary progressive aphasia) and typical amnestic Alzheimer's disease, in relation to 33 healthy controls (18 female; aged 54-78). Participants heard famous melodies containing no deviants or one of three types of deviant note-acoustic (white-noise burst), syntactic (key-violating pitch change) or semantic (key-preserving pitch change). Using a regression model that took elementary perceptual, executive and musical competence into account, we assessed accuracy detecting melodic deviants and simultaneously recorded pupillary responses and related these to deviant surprise value (information-content) and carrier melody predictability (entropy), calculated using an unsupervised machine learning model of music. Neuroanatomical associations of deviant detection accuracy and coupling of detection to deviant surprise value were assessed using voxel-based morphometry of patients' brain MRI. Whereas Alzheimer's disease was associated with normal deviant detection accuracy, behavioural and semantic variant frontotemporal dementia syndromes were associated with strikingly similar profiles of impaired syntactic and semantic deviant detection accuracy and impaired behavioural and autonomic sensitivity to deviant information-content (all P < 0.05). On the other hand, non-fluent-agrammatic primary progressive aphasia was associated with generalized impairment of deviant discriminability (P < 0.05) due to excessive false-alarms, despite retained behavioural and autonomic sensitivity to deviant information-content and melody predictability. Across the patient cohort, grey matter correlates of acoustic deviant detection accuracy were identified in precuneus, mid and mesial temporal regions; correlates of syntactic deviant detection accuracy and information-content processing, in inferior frontal and anterior temporal cortices, putamen and nucleus accumbens; and a common correlate of musical salience coding in supplementary motor area (all P < 0.05, corrected for multiple comparisons in pre-specified regions of interest). Our findings suggest that major dementias have distinct profiles of sensory 'surprise' processing, as instantiated in music. Music may be a useful and informative paradigm for probing the predictive decoding of complex sensory environments in neurodegenerative proteinopathies, with implications for understanding and measuring the core pathophysiology of these diseases.

Laughter as a paradigm of socio-emotional signal processing in dementia.

Laughter is a fundamental communicative signal in our relations with other people and is used to convey a diverse repertoire of social and emotional information. It is therefore potentially a useful probe of impaired socio-emotional signal processing in neurodegenerative diseases. Here we investigated the cognitive and affective processing of laughter in forty-seven patients representing all major syndromes of frontotemporal dementia, a disease spectrum characterised by severe socio-emotional dysfunction (twenty-two with behavioural variant frontotemporal dementia, twelve with semantic variant primary progressive aphasia, thirteen with nonfluent-agrammatic variant primary progressive aphasia), in relation to fifteen patients with typical amnestic Alzheimer's disease and twenty healthy age-matched individuals. We assessed cognitive labelling (identification) and valence rating (affective evaluation) of samples of spontaneous (mirthful and hostile) and volitional (posed) laughter versus two auditory control conditions (a synthetic laughter-like stimulus and spoken numbers). Neuroanatomical associations of laughter processing were assessed using voxel-based morphometry of patients' brain MR images. While all dementia syndromes were associated with impaired identification of laughter subtypes relative to healthy controls, this was significantly more severe overall in frontotemporal dementia than in Alzheimer's disease and particularly in the behavioural and semantic variants, which also showed abnormal affective evaluation of laughter. Over the patient cohort, laughter identification accuracy was correlated with measures of daily-life socio-emotional functioning. Certain striking syndromic signatures emerged, including enhanced liking for hostile laughter in behavioural variant frontotemporal dementia, impaired processing of synthetic laughter in the nonfluent-agrammatic variant (consistent with a generic complex auditory perceptual deficit) and enhanced liking for numbers ('numerophilia') in the semantic variant. Across the patient cohort, overall laughter identification accuracy correlated with regional grey matter in a core network encompassing inferior frontal and cingulo-insular cortices; and more specific correlates of laughter identification accuracy were delineated in cortical regions mediating affective disambiguation (identification of hostile and posed laughter in orbitofrontal cortex) and authenticity (social intent) decoding (identification of mirthful and posed laughter in anteromedial prefrontal cortex) (all p < .05 after correction for multiple voxel-wise comparisons over the whole brain). These findings reveal a rich diversity of cognitive and affective laughter phenotypes in canonical dementia syndromes and suggest that laughter is an informative probe of neural mechanisms underpinning socio-emotional dysfunction in neurodegenerative disease.

No differences in physical activity between children with overweight and children of normal-weight.

BACKGROUND: The aim of this study was to investigate the differences in objectively measured physical activity and in self-reported physical activity between overweight and normal-weight children. METHODS: Data from a prospective cohort study including children, presenting at the participating general practices in the south-west of the Netherlands, were used. Children (aged 4-15 years) were categorized as normal-weight or overweight using age- and sex specific cut-off points. They wore an ActiGraph accelerometer for one week to register physical activity, and filled out a diary for one week about physical activity. RESULTS: A total of 57 children were included in this study. Overweight children spent significantly less percentage time per day in sedentary behavior (ß - 1.68 (95%CI -3.129, - 0.07)). There were no significant differences in percentage time per day spent in moderate to vigorous physical activity (ß 0.33 (- 0.11, 0.78)). No significant differences were found between children of normal-weight and overweight in self-reported measures of physical activity. CONCLUSIONS: Overweight children are not less physically active than normal-weight children, which may be associated with the risen awareness towards overweight/obesity and with implemented interventions for children with overweight/obesity.

The functional neuroanatomy of emotion processing in frontotemporal dementias.

Impaired processing of emotional signals is a core feature of frontotemporal dementia syndromes, but the underlying neural mechanisms have proved challenging to characterize and measure. Progress in this field may depend on detecting functional changes in the working brain, and disentangling components of emotion processing that include sensory decoding, emotion categorization and emotional contagion. We addressed this using functional MRI of naturalistic, dynamic facial emotion processing with concurrent indices of autonomic arousal, in a cohort of patients representing all major frontotemporal dementia syndromes relative to healthy age-matched individuals. Seventeen patients with behavioural variant frontotemporal dementia [four female; mean (standard deviation) age 64.8 (6.8) years], 12 with semantic variant primary progressive aphasia [four female; 66.9 (7.0) years], nine with non-fluent variant primary progressive aphasia [five female; 67.4 (8.1) years] and 22 healthy controls [12 female; 68.6 (6.8) years] passively viewed videos of universal facial expressions during functional MRI acquisition, with simultaneous heart rate and pupillometric recordings; emotion identification accuracy was assessed in a post-scan behavioural task. Relative to healthy controls, patient groups showed significant impairments (analysis of variance models, all P < 0.05) of facial emotion identification (all syndromes) and cardiac (all syndromes) and pupillary (non-fluent variant only) reactivity. Group-level functional neuroanatomical changes were assessed using statistical parametric mapping, thresholded at P < 0.05 after correction for multiple comparisons over the whole brain or within pre-specified regions of interest. In response to viewing facial expressions, all participant groups showed comparable activation of primary visual cortex while patient groups showed differential hypo-activation of fusiform and posterior temporo-occipital junctional cortices. Bi-hemispheric, syndrome-specific activations predicting facial emotion identification performance were identified (behavioural variant, anterior insula and caudate; semantic variant, anterior temporal cortex; non-fluent variant, frontal operculum). The semantic and non-fluent variant groups additionally showed complex profiles of central parasympathetic and sympathetic autonomic involvement that overlapped signatures of emotional visual and categorization processing and extended (in the non-fluent group) to brainstem effector pathways. These findings open a window on the functional cerebral mechanisms underpinning complex socio-emotional phenotypes of frontotemporal dementia, with implications for novel physiological biomarker development.

Differences in respiratory consultations in primary care between underweight, normal-weight, and overweight children.

This prospective cohort study investigates whether the suggested association between weight status and respiratory complaints in open populations is also reflected in the frequency of consultations for respiratory complaints at the general practice. Children aged 2-18 years presenting at one of the participating general practices in the Netherlands could be included. Electronic medical files were used to extract data on consultations. Logistic regression analyses and negative binomial regression analyses were used to assess the associations between weight status and the presence, and frequency of respiratory consultations, respectively, during 2-year follow-up. Subgroup analyses were performed in children aged 2-6, 6-12, and 12-18 years old. Of the 617 children, 115 (18.6%) were underweight, 391 (63.4%) were normal-weight, and 111 (18%) were overweight. Respiratory consultations were not more prevalent in underweight children compared to normal-weight children (odds ratio (OR) 0.87, 95% confidence inteval (CI) 0.64-1.10), and in overweight children compared to normal-weight children (OR 1.33, 95% CI 0.99-1.77). Overweight children aged 12-18 years had more respiratory consultations (OR 2.14, 95% CI 1.14-4.01), more asthma-like consultations (OR 3.94, 95%CI 1.20-12.88), and more respiratory allergy-related consultations (OR 3.14, 95% CI 1.25-7.86) than normal-weight children. General practitioners should pay attention to weight loss as part of the treatment of respiratory complaints in overweight and obese children.

Frontotemporal Dementia: A Clinical Review.

Frontotemporal dementias are a clinically, neuroanatomically, and pathologically diverse group of diseases that collectively constitute an important cause of young-onset dementia. Clinically, frontotemporal dementias characteristically strike capacities that define us as individuals, presenting broadly as disorders of social behavior or language. Neurobiologically, these diseases can be regarded as "molecular nexopathies," a paradigm for selective targeting and destruction of brain networks by pathogenic proteins. Mutations in three major genes collectively account for a substantial proportion of behavioral presentations, with far-reaching implications for the lives of families but also potential opportunities for presymptomatic diagnosis and intervention. Predicting molecular pathology from clinical and radiological phenotypes remains challenging; however, certain patterns have been identified, and genetically mediated forms of frontotemporal dementia have spearheaded this enterprise. Here we present a clinical roadmap for diagnosis and assessment of the frontotemporal dementias, motivated by our emerging understanding of the mechanisms by which pathogenic protein effects at the cellular level translate to abnormal neural network physiology and ultimately, complex clinical symptoms. We conclude by outlining principles of management and prospects for disease modification.

General practitioners cannot rely on reported weight and height of children.

AIM: The aim of this study is to investigate the differences between reported and measured weight and height for underweight, normal-weight, and overweight children, particularly in a general practitioner setting. BACKGROUND: Screening, signaling, and treatment of childhood obesity by the general practitioner depends on accurate weight and height measurements. METHODS: Data on reported and measured weight and height from a cohort including 715 normal-weight and overweight children aged 2-17 were used. Means of reported and measured weight and height were compared using the paired T-test. FINDINGS: Of the 715 included children, 17.5% were defined as being underweight, 63.2% normal-weight, and 19.3% overweight according to direct measured height and weight. In the age group 2-8 years, parents of underweight children reported a significantly higher weight than measured weight [mean differences (MD) 0.32 kg (0.02, 0.62)], whereas parents of overweight young children reported a significantly lower weight [MD -1.08 kg (-1.77, -0.39)]. In the age group 9-17 years, normal-weight [MD -0.51 kg (-0.79, -0.23)] and overweight children [MD -1.28 kg (-2.08, -0.47)] reported a significantly lower weight than measured weight. CONCLUSIONS: General practitioners cannot rely on reported weight and height measures from parents and children. In case of suspected under- or overweight in children, it should be advised to measure weight and height in general practice.

The effect of a multidisciplinary intervention program for overweight and obese children on cardiorespiratory fitness and blood pressure.

BACKGROUND: Multidisciplinary intervention programs for overweight and obese children mainly focus on reducing bodyweight and body mass index (BMI), but they may also positively impact blood pressure (BP), and cardiorespiratory fitness (CRF), which is a stronger predictor for all-cause mortality than BMI. OBJECTIVE: To evaluate whether Kids4Fit, a multidisciplinary weight reduction program, has a positive effect on CRF and BP in overweight and obese children in socially deprived areas. METHODS: A quasi-experimental study design with a waiting list control period including children who participated in a multidisciplinary intervention program of 12 weeks was set-up. Blood pressure measurements and shuttle-run test (SRT) were performed at baseline, at the start of the intervention, at the end of intervention and after 52 weeks. The effect of Kids4Fit on BP and on SRT scores were analyzed using mixed models. RESULTS: A total of 154 children were included [mean age 8.5 years (SD 1.8)]. No significant change was seen in systolic BP percentiles at 52 weeks after start of the Kids4Fit intervention (ß 0.08, (95%CI -0.06, 0.22)). Diastolic BP percentiles increased significantly over time (ß 0.20 (0.08, 0.31)). Effect plots showed an initial significant increase of the SRT scores but this effect diluted after the intervention. CONCLUSION: A local multidisciplinary intervention program in deprived areas had a significant positive effect on CRF, but this effect diluted after the intervention. Diastolic BP percentiles significantly increased over time. However, systolic BP did not change over time.

Overweight and obese children do not consult their general practitioner more often than normal weight children for musculoskeletal complaints during a 2-year follow-up.

BACKGROUND: Childhood obesity is associated with self-reported musculoskeletal complaints, injuries and fractures. In the current study, we investigated the association between weight status of children and the frequency and type of musculoskeletal consultations at the general practitioner (GP) during a 2-year follow-up. METHODS: Data from a prospective longitudinal cohort study including children aged 2-18 years presenting in general practices in the Netherlands were used. Height and weight were measured at baseline, at 6-month, 1-year and 2-year follow-ups. Electronic medical files were used to collect information on the frequency and type of consultations at the GP during the 2-year follow-up period. Associations between weight status and frequency and type of GP consultations were calculated. RESULTS: Of the 617 included children, 111 (18%) were overweight or obese and 506 (82%) were non-overweight. Overweight children were significantly older (mean age in years (SD): 9.8 (3.6)vs7.8 (4.0), p=0.004). Overweight children consulted the GP in general significantly more frequent during the 2-year follow-up than non-overweight children (mean (SD): 7.3 (5.7)vs6.7 (5.4), OR 1.09, 95% CI 1.01 to 1.18). No significant difference was seen in the number of overweight and non-overweight children consulting their GP for musculoskeletal complaints (OR 1.20 (0.86 to 1.68)). Additionally, no significant difference between overweight and non-overweight children was seen for the number of consultations for further specified musculoskeletal disorders. CONCLUSION: No association was seen between childhood weight status and the frequency and type of musculoskeletal consultations at the GP during a 2-year follow-up.

BMI predicts exercise induced bronchoconstriction in asthmatic boys.

BACKGROUND: Exercise induced bronchoconstriction (EIB) is a frustrating morbidity of asthma in children. Obesity has been associated with asthma and with more severe EIB in asthmatic children. OBJECTIVES: To quantify the effect of BMI on the risk of the occurrence of EIB in children with asthma. METHODS: Data were collected from six studies in which exercise challenge tests were performed according to international guidelines. We included 212 Children aged 7-18 years, with a pediatrician-diagnosed mild-to-moderate asthma. RESULTS: A total of 103 of 212 children (49%) had a positive exercise challenge (fall of FEV1 ≥ 13%). The severity of EIB, as measured by the maximum fall in FEV1 , was significantly greater in overweight and obese children compared to normal weight children (respectively 23.9% vs 17.9%; P = 0.045). Asthmatic children with a BMI z-score around +1 had a 2.9-fold higher risk of the prevalence of EIB compared to children with a BMI z-score around the mean (OR 2.9; 95%CI: 1.3-6.1; P < 0.01). An increase in BMI z-score of 0.1 in boys led to a 1.4-fold increased risk of EIB (OR 1.4; 95%CI: 1.0-1.9; P = 0.03). A reduction in pre-exercise FEV1 was associated with a higher risk of EIB (last quartile six times higher risk compared to highest quartile (OR 6.1 [95%CI 2.5-14.5]). CONCLUSIONS: The severity of EIB is significantly greater in children with overweight and obesity compared to non-overweight asthmatic children. Furthermore, this study shows that the BMI-z-score, even with a normal weight, is strongly associated with the incidence of EIB in asthmatic boys.

Preparatory planning framework for Created Out of Mind: Shaping perceptions of dementia through art and science.

Created Out of Mind is an interdisciplinary project, comprised of individuals from arts, social sciences, music, biomedical sciences, humanities and operational disciplines. Collaboratively we are working to shape perceptions of dementias through the arts and sciences, from a position within the Wellcome Collection. The Collection is a public building, above objects and archives, with a porous relationship between research, museum artefacts, and the public.  This pre-planning framework will act as an introduction to Created Out of Mind. The framework explains the rationale and aims of the project, outlines our focus for the project, and explores a number of challenges we have encountered by virtue of working in this way.

Early knee osteoarthritis is evident one year following anterior cruciate ligament reconstruction: a magnetic resonance imaging evaluation.

OBJECTIVE: To determine the prevalence and factors associated with knee osteoarthritis (OA) defined by magnetic resonance imaging (MRI) and specific OA features on MRI 1 year after anterior cruciate ligament reconstruction (ACLR). METHODS: Isotropic 3.0T MRI scans were obtained for 111 participants (71 men; mean ± SD age 30 ± 8 years) 1 year after ACLR as well as for 20 age-, sex-, and activity level-matched uninjured controls. The MRI OA Knee Score was used to score specific OA features. MRI-defined tibiofemoral and patellofemoral OA was evaluated based on published criteria. Logistic regression identified factors associated with MRI-defined OA and specific OA features after ACLR. RESULTS: Following ACLR, medial and lateral tibiofemoral OA on MRI was observed in 7 participants (6%) and 12 participants (11%), respectively, while 19 participants (17%) had patellofemoral OA on MRI. The femoral trochlea was the region most affected by bone marrow lesions (19% of participants), cartilage lesions (31% of participants), and osteophytes (37% of participants). Meniscectomy at the time of ACLR (odds ratio 6.8 [95% confidence interval 2.0-23.3]) and body mass index (BMI) >25 kg/m(2) (odds ratio 3.0 [95% confidence interval 1.3-6.9]) predicted MRI-defined tibiofemoral OA and osteophytes, respectively. Men had higher odds of patellofemoral osteophytes (odds ratio 6.3 [95% confidence interval 2.4-16.2]). No uninjured controls had tibiofemoral or patellofemoral OA on MRI, and specific OA features were uncommon. CONCLUSION: OA 1 year following ACLR was more common than previously recognized, while being absent in uninjured control knees. The patellofemoral compartment seems to be at particular risk for early OA after ACLR, especially in men. The association with meniscectomy and BMI demonstrates the construct validity of MRI criteria.

Effects of dietary induced weight loss on exercise-induced bronchoconstriction in overweight and obese children.

RATIONALE: Previous studies showed that obesity in asthmatic children is associated with more severe exercise-induced bronchoconstriction (EIB), compared with non-obese asthmatic children. This study investigates the effect of weight loss on EIB in overweight and obese asthmatic children. METHODS: In this intervention study, children aged 8-18 years with EIB and moderate to severe overweight, followed a diet based on healthy daily intake for 6 weeks. Before and after the diet period they underwent an exercise challenge test in cold air. Primary outcome was change in exercise-induced fall in FEV1 and relation between weight loss and EIB. Secondary outcomes were changes in recovery of FEV1 ("area under the curve"; AUC), fraction of exhaled nitric oxide (FeNO) and scores of the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) and Asthma Control Questionnaire (ACQ). RESULTS: Twenty children completed the study. After the diet period, weight, and body mass index (BMI) were significantly reduced (changes respectively -2.6% and -1.5 kg/m(2), P < 0.01). There was a significant improvement of the percentage exercise-induced fall in FEV1 (30.6% vs. 21.8%, P < 0.01), AUC and PAQLQ score. The reduction in BMI z-score was significantly related to the reduction in the percentage exercise-induced fall in FEV1 in children that lost weight (r = 0.53, P = 0.03). There were no changes in FeNO and ACQ. CONCLUSIONS: Dietary induced weight loss in overweight and obese asthmatic children leads to significant reduction in severity of EIB and improvement of the quality of life. The reduction in BMI z-score is significantly related to the improvement of EIB.

Assessment of exercise-induced bronchoconstriction in adolescents and young children.

Recent research shows important differences in exercise-induced bronchoconstriction (EIB) between children and adults, suggesting a different pathophysiology of EIB in children. Although exercise can trigger classic symptoms of asthma, in children symptoms can be subtle and nonspecific; parents, children, and clinicians often do not recognize EIB. With an age-adjusted protocol, an exercise challenge test can be performed in children as young as 3 years of age. However, an alternative challenge test is sometimes necessary to assess potential for EIB in children. This review summarizes age-related features of EIB and recommendations for assessing EIB in young children and adolescents.