Perceived friend support buffers against symptoms of depression in peer victimized adolescents: Evidence from a population-based cohort in South Korea.

BACKGROUND: Peer victimization is associated with an increased risk for depression, but there is less evidence on how certain factors such as friend support can buffer this association. This study investigated the associations between friend support and depressive symptoms among victimized and non-victimized adolescent girls and boys from South Korea. METHODS: Participants includes 2258 students from the Korean Children and Youth Panel Survey, a nationally representative sample of middle school students in South Korea. Self-reported perceived friend support, depressive symptoms and peer victimization were measured using validated scales during middle school year 3 (mean age= 15.7 years). RESULTS: The association between peer victimization and depressive symptoms varied by sex (p for sex by peer victimization interaction<0.05). Peer victimization was more strongly associated with same year depressive symptoms in girls (ß=0.55) than boys (ß=0.24). After controlling for key confounders, including prior year mental health symptoms, higher levels of friend support were found to attenuate the association between peer victimization and depressive symptoms (p for friend support by peer victimization interaction <0.05). Peer victimization was associated with more depressive symptoms for adolescents with low and moderate friend support, but not those with high friend support. LIMITATIONS: Peer victimization, depressive symptoms, and friend support, were self-reported and measured the same year. CONCLUSIONS: Friend support protects victimized South Korean adolescents from the negative effect of peer victimization on depressive symptoms, hence contributes to closing the gap in depression between victimized and non-victimized adolescents.

Nutritional Status and Frailty in Community-Dwelling Older Korean Adults: The Korean Frailty and Aging Cohort Study.

OBJECTIVES: To examine the association between nutritional status and frailty in older adults. DESIGN: Cross-sectional study. SETTING: Community-dwelling older adults were recruited from 10 study sites in South Korea. PARTICIPANTS: 1473 volunteers aged 70-84 years without severe cognitive impairment and who participated in the Korean Frailty and Aging Cohort Study (KFACS) conducted in 2016. MEASUREMENTS: Nutritional status was measured using the Mini Nutritional Assessment Short Form (MNA-SF). Frailty was assessed with the Fried's frailty index. The relationship between nutritional status and frailty was examined using the multinomial regression analysis, adjusting for covariates. RESULTS: Of the respondents 14.3% had poor nutrition (0.8% with malnutrition, 13.5% at risk of malnutrition). There were 10.7% who were frail, with 48.5% being prefrail, and 40.8% robust. Poor nutrition was related to a significantly increased risk of being prefrail (odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.09-2.32) and frail (OR: 3.30, 95% CI: 1.96-5.54). CONCLUSION: Poor nutritional status is strongly associated with frailty in older adults. More research to understand the interdependency between nutritional status and frailty may lead to better management of the two geriatric conditions.

Association between Cognitive Impairment, Vascular Disease and All-Cause Mortality.

OBJECTIVE: The purpose of this study was to investigate the association between elder's cognitive impairment and mortality. Additionally, interaction between cognitive impairment and cardio- and cerebrovascular diseases was considered. METHODS: Data from the Korean Longitudinal Study of Aging (KLoSA) from 2006 to 2014 was assessed using 10,026 participants at baseline with no missing information. Chi-square test, log-rank test, and Cox proportional hazards models were used to investigate the association between cognitive impairment and mortality. RESULTS: Cognitive impairment was significantly associated with mortality. With normal cognitive functioning group as reference: HR=2.329 (p<.0001) for severe cognitive impairment, HR=1.238 (p.009) for mild cognitive impairment. The association remained significant even after considering for cardio- and cerebrovascular diseases. CONCLUSION: This study provided additional support to previous findings in regards to the relationship between cognitive impairment and mortality. Worse cognitive functioning increased the risk of mortality and the presence of cardio- and cerebrovascular diseases exacerbated this relationship.

Regional pulmonary inflammation in an endotoxemic ovine acute lung injury model.

The regional distribution of inflammation during acute lung injury (ALI) is not well known. In an ovine ALI model we studied regional alveolar inflammation, surfactant composition, and CT-derived regional specific volume change (sVol) and specific compliance (sC). 18 ventilated adult sheep received IV lipopolysaccharide (LPS) until severe ALI was achieved. Blood and bronchoalveolar lavage (BAL) samples from apical and basal lung regions were obtained at baseline and injury time points, for analysis of cytokines (IL-6, IL-1ß), BAL protein and surfactant composition. Whole lung CT images were obtained in 4 additional sheep. BAL protein and IL-1ß were significantly higher in injured apical vs. basal regions. No significant regional surfactant composition changes were observed. Baseline sVol and sC were lower in apex vs. base; ALI enhanced this cranio-caudal difference, reaching statistical significance only for sC. This study suggests that apical lung regions show greater inflammation than basal ones during IV LPS-induced ALI which may relate to differences in regional mechanical events.

In vivo micro-CT lung imaging via a computer-controlled intermittent iso-pressure breath hold (IIBH) technique.

Respiratory research with mice using micro-computed tomography (micro-CT) has been predominantly hindered by the limited resolution and signal-to-noise ratio (SNR) as a result of respiratory motion artefacts. In this study, we develop a novel technique for capturing the lung microstructure in vivo using micro-CT, through a computer-controlled intermittent iso-pressure breath hold (IIBH), to reduce respiratory motion, increasing resolution and SNR of reconstructed images. We compare four gating techniques, i.e. no gating, late expiratory (LE) gating, late inspiratory (LI) gating and finally intermittent iso-pressure breath hold (IIBH) gating. Quantitatively, we compare several common image analysis methods used to extract valuable physiologic and anatomic information from the respiratory system, and show that the IIBH technique produces the most representative and repeatable results.

Na,K-ATPase in several tissues of the rat: tissue-specific expression of subunit mRNAs and enzyme activity.

The relative contents of Na,K-ATPase subunit mRNAs in rat renal cortex, ventricular myocardium, skeletal muscle (hind limb), liver and brain (cerebrum) were measured. Expressed per unit DNA, mRNA alpha 1 content was approximately 2-fold greater in the kidney and brain as compared to either heart, skeletal muscle or liver. The hierarchy of mRNA alpha 2 expression was brain > skeletal muscle > heart, whereas mRNA alpha 3 was restricted to brain. Beta 1 subunit mRNA content in both kidney and brain exceeded the abundance of liver mRNA beta 1 by approximately 7-fold. In all tissues examined, the combined abundances of the alpha subunit mRNAs exceeded the content of mRNA beta 1. The hierarchy of Na,K-ATPase activity expressed per unit DNA was brain > kidney > skeletal muscle = heart > liver. The sum of mRNA alpha as well as mRNA beta 1 content, expressed per g of tissue, was highest in brain and kidney. A statistically significant correlation between mRNA beta 1 content and Na,K-ATPase activity was evident.

Induction of Na(+)-K(+)-ATPase and its subunit mRNAs by serum in a rat liver cell line.

Addition of serum to confluent Clone 9 cells increased the protein, RNA, and DNA content per plate of cells; the increments became manifest within 3-6 h and were sustained for the 48-h duration of study. After the addition of serum, Na(+)-K(+)-ATPase activity was stimulated 1.25- and 1.45-fold at 6 and 12 h, respectively. In cells preincubated in the absence of serum for 24 h, addition of serum increased the abundances of Na(+)-K(+)-ATPase subunit mRNAs, mRNA alpha 1 and mRNA beta, coordinately by approximately 2- and 2.7-fold at 3 h, an effect that preceded the stimulation of Na(+)-K(+)-ATPase activity. The serum-induced increments in subunit mRNA abundances were further enhanced by the combined presence of serum and cycloheximide; mRNA alpha 1 and mRNA beta abundances were also augmented by cycloheximide alone (approximately 2.5- and 9.2-fold at 6 h, respectively). In cells incubated in the absence of serum, the half-lives of mRNA alpha 1 and mRNA beta, estimated from decrements in their abundances after the addition of actinomycin D, were 12 and 10 h, respectively. These data demonstrate that serum enhances Na(+)-K(+)-ATPase subunit mRNA abundance and enzyme activity in Clone 9 cells. Comparison of the estimated half-lives of Na(+)-K(+)-ATPase subunit mRNAs with the observed increments in their abundances at 3 h suggests that the serum-induced increases in mRNA alpha 1 and mRNA beta abundances are in large part due to enhanced synthesis of these mRNAs.