Quality of dietary macronutrients is associated with glycemic outcomes in adults with cystic fibrosis.

Objective: Poor diet quality contributes to metabolic dysfunction. This study aimed to gain a greater understanding of the relationship between dietary macronutrient quality and glucose homeostasis in adults with cystic fibrosis (CF). Design: This was a cross-sectional study of N = 27 adults with CF with glucose tolerance ranging from normal (n = 9) to prediabetes (n = 6) to being classified as having cystic fibrosis-related diabetes (CFRD, n = 12). Fasted blood was collected for analysis of glucose, insulin, and C-peptide. Insulin resistance was assessed by Homeostatic Model Assessment for Insulin Resistance (HOMA2-IR). Subjects without known CFRD also underwent a 2-h oral glucose tolerance test. Three-day food records were used to assess macronutrient sources. Dietary variables were adjusted for energy intake. Statistical analyses included ANOVA, Spearman correlations, and multiple linear regression. Results: Individuals with CFRD consumed less total fat and monounsaturated fatty acids (MUFA) compared to those with normal glucose tolerance (p < 0.05). In Spearman correlation analyses, dietary glycemic load was inversely associated with C-peptide (rho = -0.28, p = 0.05). Total dietary fat, MUFA, and polyunsaturated fatty acids (PUFA) were positively associated with C-peptide (rho = 0.39-0.41, all p < 0.05). Plant protein intake was inversely related to HOMA2-IR (rho = -0.28, p = 0.048). Associations remained significant after adjustment for age and sex. Discussion: Improvements in diet quality are needed in people with CF. This study suggests that higher unsaturated dietary fat, higher plant protein, and higher carbohydrate quality were associated with better glucose tolerance indicators in adults with CF. Larger, prospective studies in individuals with CF are needed to determine the impact of diet quality on the development of CFRD.

Neural responding during uncertain threat anticipation in pediatric anxiety.

Excessive fear responses to uncertain threat are a key feature of anxiety disorders (ADs), though most mechanistic work considers adults. As ADs onset in childhood and confer risk for later psychopathology, we sought to identify conditions of uncertain threat that distinguish 8-17-year-old youth with AD (n = 19) from those without AD (n = 33), and assess test-retest reliability of such responses in a companion sample of healthy adults across three sites (n = 19). In an adapted uncertainty of threat paradigm, visual cues parametrically signaled threat of aversive stimuli (fear faces) in 25 % increments (0 %, 25 %, 50 %, 100 %), while participants underwent functional magnetic resonance imaging (fMRI). We compared neural response elicited by cues signaling different degrees of probability regarding the subsequent delivery of fear faces. Overall, youth displayed greater engagement of bilateral inferior parietal cortex, fusiform gyrus, and lingual gyrus during uncertain threat anticipation in general. Relative to healthy youth, AD youth exhibited greater activation in ventrolateral prefrontal cortex (vlPFC)/BA47 during uncertain threat anticipation in general. Further, AD differed from healthy youth in scaling of ventral striatum/sgACC activation with threat probability and attenuated flexibility of responding during parametric uncertain threat. Complementing these results, significant, albeit modest, cross-site test-retest reliability in these regions was observed in an independent sample of healthy adults. While preliminary due to a small sample size, these findings suggest that during uncertainty of threat, AD youth engage vlPFC regions known to be involved in fear regulation, response inhibition, and cognitive control. Findings highlight the potential of isolating neural correlates of threat anticipation to guide treatment development and translational work in youth.

Social relevance modulates multivariate neural representations of threat generalization in children and adults.

Few studies have examined threat generalization across development and no developmental studies have compared the generalization of social versus nonsocial threat, making it difficult to identify contextual factors that contribute to threat learning across development. The present study assessed youth and adults' multivoxel neural representations of social versus nonsocial threat stimuli. Twenty adults (Mage  = 25.7 ± 4.9) and 16 youth (Mage  = 14.1 ± 1.7) completed two conditioning and extinction recall paradigms: one social and one nonsocial paradigm. Three weeks after conditioning, participants underwent a functional magnetic resonance imaging extinction recall task that presented the extinguished threat cue (CS+), a safety cue (CS-), and generalization stimuli (GS) consisting of CS-/CS+ blends. Across age groups, neural activity patterns and self-reported fear and memory ratings followed a linear generalization gradient for social threat stimuli and a quadratic generalization gradient for nonsocial threat stimuli, indicating enhanced threat/safety discrimination for social relative to nonsocial threat stimuli. The amygdala and ventromedial prefrontal cortex displayed the greatest neural pattern differentiation between the CS+ and GS/CS-, reinforcing their role in threat learning and extinction recall. Contrary to predictions, age did not influence threat representations. These findings highlight the importance of the social relevance of threat on generalization across development.

A meta-analysis of the association between adolescent social media use and depressive symptoms.

BACKGROUND: The association of adolescent social media use with mental health symptoms, especially depression, has recently attracted a great deal of interest in public media as well as the scientific community. Some studies have cited statistically significant associations between adolescent social media use and depression and have proposed that parents must regulate their adolescents' social media use in order to protect their mental health. METHOD: In order to rigorously assess the size of the effect that has been reported in the current scientific literature, we conducted a meta-analysis of studies that measured the association between social media use specifically and depressive symptoms amongst early- to mid- adolescents (11-18 years-old). We searched Psychnet, PubMed, and Web of Science with the following terms: online social networks, social media, internet usage, facebook, twitter, instagram, myspace, snapchat, and depression. RESULTS: We found a small but significant positive correlation (k=12 studies, r=.11, p<.01) between adolescent social media use and depressive symptoms. There was also high heterogeneity (I2=95.22%) indicating substantial variation among studies. CONCLUSIONS: High heterogeneity along with the small overall effect size observed in the relationship between self-reported social media use and depressive symptoms suggests that other factors are likely to act as significant moderators of the relationship. We suggest that future research should be focused on understanding which types of use may be harmful (or helpful) to mental health, rather than focusing on overall use measures that likely reflect highly heterogeneous exposures.

Factor Structure of the Early Adolescent Temperament Questionnaire-Revised.

Early adolescence (typically aged 9-15 years) is a period of dramatic developmental change, and individual differences in temperament is likely to be an important predictor of the success with which individuals negotiate this period of life. Moreover, early adolescent temperament cannot be adequately captured by measures designed for other age groups. This study examined the empirical validity of the proposed temperament factors of the Early Adolescent Temperament Questionnaire-Revised (EATQ-R) in a large representative sample of 2,453 early adolescents aged between 10 and 12 years of age, and compared it with models that include cross-loadings between items and first-order factors, as well as first- and second-order factors. Furthermore, the reproducibility of the factor structure established by using a cross validation approach. Adding cross-loadings to the EATQ-R fit the data substantially better, resulting in an overall good fit that the original EATQ-R model did not achieve. However, the conceptual interpretation of the first- and second-order factor structures were not substantially altered even with this addition of cross-loadings. Future research should establish the construct validity of the first- and second-order factors as measured by this empirically based factor structure.

Visceral adipose tissue is associated with poor diet quality and higher fasting glucose in adults with cystic fibrosis.

BACKGROUND: Body fat distribution and diet quality influence clinical outcomes in general populations but are understudied in individuals with cystic fibrosis (CF). The aim of this pilot study was to assess body fat distribution and diet quality in relation to fasting glucose and lung function in adults with CF. METHODS: Subjects were 24 adults (ages 18-50) with CF and 25 age-matched controls. The Healthy Eating Index 2015 (HEI-2015) was calculated from 3-day food records and data were adjusted per 1000 kcal. Whole and regional body composition, including visceral adipose tissue (VAT), was assessed by dual energy X-ray absorptiometry. RESULTS: Subjects with CF reported more added sugar intake [26.1 (IQR 18.1) vs. 12.9 (12.5) g/1000 kcal, p < 0.001] and had lower HEI-2015 scores [48.3 (IQR 9.9) vs. 63.9 (27.3), p < 0.001] compared to controls. There were no differences in BMI, total body fat, or lean body mass (LBM) between subjects with CF and controls (p > 0.05 for all), although subjects with CF had higher VAT than control subjects [0.3 (IQR 0.3) vs 0.1 (0.3) kg, p = 0.02]. Among subjects with CF, VAT was positively associated with added sugar intake (p < 0.001) and fasting blood glucose (p = 0.04). Lung function was positively associated with BMI (p = 0.005) and LBM (p = 0.03) but not with adiposity indicators. CONCLUSIONS: These novel data link body fat distribution with diet quality and fasting glucose levels in adults with CF, whereas LBM was associated with lung function. This study highlights the importance of increasing diet quality and assessing body composition and fat distribution in the CF population.

Bolus Weekly Vitamin D3 Supplementation Impacts Gut and Airway Microbiota in Adults With Cystic Fibrosis: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial.

Context: Disruption of gut microbiota may exacerbate severity of cystic fibrosis (CF). Vitamin D deficiency is a common comorbidity in patients with CF that may influence composition of the gut microbiota. Objectives: Compare microbiota of vitamin D-sufficient and -insufficient CF patients and assess impact of a weekly high-dose vitamin D3 bolus regimen on gut and airway microbiome in adults with CF and vitamin D insufficiency (25-hydroxyvitamin D < 30 ng/mL). Design: Forty-one subjects with CF were classified into two groups: vitamin D insufficient (n = 23) and vitamin D sufficient (n = 18). Subjects with vitamin D insufficiency were randomized to receive 50,000 IU of oral vitamin D3 or placebo weekly for 12 weeks. Sputum and stool samples were obtained pre- and postintervention and 16S ribosomal RNA genes sequenced using Illumina MiSeq technology. Results: Gut microbiota differed significantly based on vitamin D status with Gammaproteobacteria, which contain numerous, potentially pathogenic species enriched in the vitamin D-insufficient group. Principal coordinates analysis showed differential gut microbiota composition within the vitamin D-insufficient patients following 12 weeks treatment with placebo or vitamin D3 (permutation multivariate analysis of variance = 0.024), with Lactococcus significantly enriched in subjects treated with vitamin D3, whereas Veillonella and Erysipelotrichaceae were significantly enriched in patients treated with placebo. Conclusion: This exploratory study suggests that vitamin D insufficiency is associated with alterations in microbiota composition that may promote inflammation and that supplementation with vitamin D has the potential to impact microbiota composition. Additional studies to determine the impact of vitamin D on microbiota benefit clinical outcomes in CF are warranted.

Presentation and validation of the DuckEES child and adolescent dynamic facial expressions stimulus set.

The stimulus sets presently used to study emotion processing are primarily static pictures of individuals (primarily adults) making emotional facial expressions. However, the dynamic, stereotyped movements associated with emotional expressions contain rich information missing from static pictures, such as the difference between happiness and pride. We created a set of 1.1 s dynamic emotional facial stimuli representing boys and girls aged 8-18. A separate group of 36 individuals (mean [M] age = 19.5 years, standard deviation [SD] = 1.95, 13 male) chose the most appropriate emotion label for each video from a superset of 250 videos. Validity and reliability statistics were performed across all stimuli, which were then used to determine which stimuli should be included in the final stimulus set. We set a criterion for inclusion of 70% agreement with the modal response made for each video. The final stimulus set contains 142 videos of 36 actors (M age = 13.24 years, SD = 2.09, 14 male) making negative (disgust, embarrassment, fear, sadness), positive (happiness, pride), and neutral facial expressions. The percent correct among the final stimuli was high (median = 88.89%; M = 88.38%, SD = 7.74%), as was reliability (κ = 0.753).

Long-range order in canary song.

Bird songs range in form from the simple notes of a Chipping Sparrow to the rich performance of the nightingale. Non-adjacent correlations can be found in the syntax of some birdsongs, indicating that the choice of what to sing next is determined not only by the current syllable, but also by previous syllables sung. Here we examine the song of the domesticated canary, a complex singer whose song consists of syllables, grouped into phrases that are arranged in flexible sequences. Phrases are defined by a fundamental time-scale that is independent of the underlying syllable duration. We show that the ordering of phrases is governed by long-range rules: the choice of what phrase to sing next in a given context depends on the history of the song, and for some syllables, highly specific rules produce correlations in song over timescales of up to ten seconds. The neural basis of these long-range correlations may provide insight into how complex behaviors are assembled from more elementary, stereotyped modules.