Sleep duration is associated with body fat and muscle mass and waist-to-height ratio beyond conventional obesity parameters in Korean adolescent boys.

While evidence has supported a strong association between sleep duration and obesity globally, results from studies of children and adolescents have been conflicting, and information about a sex-specific association has been limited. This study aimed to investigate the association of sleep duration with various parameters of obesity among South Korean adolescents. This population-based, cross-sectional study analysed the data obtained from the Korea National Health and Nutrition Examination Surveys (KNHANES) 2009 and 2010. Data of 990 adolescents were analysed. Sleep duration was based on a self-reported questionnaire. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), body fat percentage (BFP) and skeletal muscle index (SMI, appendicular skeletal muscle mass as a percentage of body weight) were assessed as parameters of obesity. Mean sleep duration in boys was associated inversely with BMI, WC, WHtR and BFP and positively with SMI. Proportions of the highest quartile of BMI, WC, WHtR and BFP and the lowest quartile of SMI increased significantly with increased sleep duration only in boys. Also, in boys, decreased sleep duration was associated significantly with the increased risk of the highest quartile of BMI, WC, WHtR and BFP and the lowest quartile of SMI, even after adjusting for confounding factors. However, in girls, there was no significant association between sleep duration and obesity parameters except WC. Periodic assessment of sleep duration in relation to body fat or muscle mass in male adolescents may be considered, especially in those who are at risk for obesity or related disorders.

My child cannot breathe while sleeping: a report of three cases and review.

BACKGROUND: Sudden breath-holding episodes during sleep in young children are potentially related to sudden infant death syndrome and other life-threatening events. Additionally, these episodes can negatively affect child's growth and development. CASE PRESENTATION: Here, we present 3 cases of preschool children with similar paroxysmal nocturnal waking events associated with choking that had different etiologies (nocturnal frontal lobe epilepsy, nocturnal gastroesophageal reflux disease, and parasomnia, respectively). CONCLUSIONS: It is important to take into consideration the fact that breath spells during sleep can occur as a rare manifestation of parasomnia due to gastroesophageal reflux or as a symptom of nocturnal frontal lobe epilepsy. Full video electroencephalography, polysomnography, and simultaneous gastric pH monitoring should be used for the differential diagnosis of sleep-related disorders, such as breath spells, in children.

Effect of socio-economic status on sleep.

AIM: Sufficient sleep is an important factor in physical and mental health. Sleep duration can be affected by socio-economic status (SES). This study aimed to examine the association between sleep duration and SES in Korean adolescents. METHODS: This study was conducted with 1608 adolescents aged 12-18 years, based on data from the 2010 to 2012 Korean National Health and Nutrition Examination Survey (KNHANES). Sleep duration was self-reported in hours and three SES indicators were used: household income, basic livelihood security programmes and type of health insurance. Confounding factors in this study were age, mental health and physical activity. RESULTS: Participants' average age was 15.6 ± 0.05 years and average sleep duration was 7.04 ± 0.05 h. There was a strong association between sleep duration and household income (P < 0.05) rather than other socio-economic indicators. In addition, it showed that sleep duration was significantly associated with age, body mass index (P < 0.05) and low mood is associated with short sleep and long sleep (>9 h/night). We found similar results in both genders, that is, that the highest income group had shorter sleep duration than the lowest income group. CONCLUSIONS: This study shows that the SES, particularly household income, is an important factor in short sleep duration in Korean adolescents. Our findings suggest that, in future investigations of the adolescent's sleep problem, attention should be paid to household income.

Effect of the prenatal maternal environments and diets on cord blood interleukin-4 and interferon -gamma: A pilot study.

BACKGROUND AND OBJECTIVE: TThe environment of a pregnant woman can affect not only fetal growth and development, but also diseases in childhood. Neonatal cord blood cytokines are commonly used to evaluate the immune development of neonates. The purpose of this study was to evaluate the effects of the environment and diet during pregnancy on IL-4 and IFN-γ in neonatal cord blood. METHOD: A total of 111 pregnant women participated in this study from April to November 2010. Allergy history, sensitization assessed by the skin prick test, dietary intake and indoor environment were evaluated. IL-4 and IFN-γ levels were measured in the complete cord blood of neonates using real-time PCR. RESULTS: There were 54 pregnant women with allergic disease. Both IL-4 and IFN-γ levels in neonatal cord blood were higher in samples from allergic mothers than in non-allergic mothers (p<0.05). The indoor environment and nutrient intake were not different between allergic and non-allergic mothers, except regarding carpet use. When the cytokine levels were divided into quartiles, lower folate and vitamin B6 intake was associated with the highest levels of IL-4 in neonatal cord blood (p<0.05), and higher folate and vitamin B6 intake was associated with highest levels of IFN-γ in neonatal cord blood. CONCLUSIONS: In this study, a strong association between IL-4 and IFN-γ levels in cord blood and the intake of folate and vitamin B6 was found, which indicates that food intake during pregnancy might have a strong influence on IL-4 and IFN-γ levels in cord blood, to a greater extent than environmental factors.

What Characteristics Confer Proteins the Ability to Induce Allergic Responses? IgE Epitope Mapping and Comparison of the Structure of Soybean 2S Albumins and Ara h 2.

Ara h 2, a peanut 2S albumin, is associated with severe allergic reactions, but a homologous protein, soybean 2S albumin, is not recognized as an important allergen. Structural difference between these proteins might explain this clinical discrepancy. Therefore, we mapped sequential epitopes and compared the structure of Ara h 2, Soy Al 1, and Soy Al 3 (Gly m 8) to confirm whether structural differences account for the discrepancy in clinical responses to these two proteins. Commercially synthesized peptides covering the full length of Ara h 2 and two soybean 2S albumins were analyzed by peptide microarray. Sera from 10 patients with peanut and soybean allergies and seven non-atopic controls were examined. The majority of epitopes in Ara h 2 identified by microarray are consistent with those identified previously. Several regions in the 2S albumins are weakly recognized by individual sera from different patients. A comparison of allergenic epitopes on peanut and soybean proteins suggests that loop-helix type secondary structures and some amino acids with a large side chain including lone electron pair, such as arginine, glutamine, and tyrosine, makes the peptides highly recognizable by the immune system. By utilizing the peptide microarray assay, we mapped IgE epitopes of Ara h 2 and two soybean 2S albumins. The use of peptide microarray mapping and analysis of the epitope characteristics may provide critical information to access the allergenicity of food proteins.

A rapid plasma neutrophil gelatinase-associated lipocalin assay for diagnosis of acute pyelonephritis in infants with acute febrile urinary tract infections: a preliminary study.

In infants with febrile urinary tract infection (UTI), the accurate rapid diagnosis of acute pyelonephritis (APN) would be valuable because early aggressive treatment reduces the risk of renal scarring. The objective of the study was to evaluate whether rapid plasma neutrophil gelatinase-associated lipocalin (NGAL) assay could be used as a diagnostic biomarker of renal parenchymal injury in infants with acute febrile UTI to distinguish APN at the bedside. This prospective observational study included 47 infants, who were admitted with a first episode of acute febrile UTI. Total UTI group was divided into the Cortical defect (UTI-CD, n = 24) group and Non-cortical defect (UTI-ND, n = 23) group, according to the result of renal scan. For the Control group, 15 infants who presented a febrile episode without any focus of bacterial infection were included. On admission, the median NGAL level (106.5 [60-476] ng/mL) in the UTI-CD group was significantly higher than that (60 [60-196] ng/mL) in the UTI-ND group and that (60 [60-197] ng/mL) in the Control group and was significantly decreased to 60 [60-306] ng/mL after an antibiotic treatment. The area under the receiver operating characteristic curves was 0.748 (95 % CI, 0.610-0.887; P = 0.003) for NGAL levels and 0.724 (95 % CI, 0.579-0.868; P = 0.009) for CRP levels. The best cutoff of NGAL level for detection of APN was founded to be 61.0 ng/mL (sensitivity, 75.0 %; specificity, 78.3 %). Although not a stand-alone test, the rapid determination of plasma NGAL level provides valuable information quickly, concerning the distinction of APN, for determining the clinical course of acute febrile UTI.

Apnea-related sleep fragmentation and poor vigilance in children with well-controlled asthma.

It has been reported that sleep problems and neurocognitive deficit in asthmatic children is prevalent. However, systematic studies on these problems in stable asthma using polysomnography have rarely been performed. We therefore investigated sleep and neurocognitive functioning in children with well-controlled asthma. Forty-three children with well-controlled, stable asthma and 31 controls (age range: 6-9 years) were enrolled in the study. Subjects were questioned for daytime sleepiness using the Paediatric Daytime Sleepiness Scale. Complete overnight polysomnography and neurocognitive function tests were performed on all subjects. Children with stable asthma had lower pulmonary function in comparison to their age-matched controls. Asthmatic children had a higher apnea-hypopnea index (P < 0.001) and apnea-hypopnea-related arousal index (P < 0.001) as compared with non-asthmatics. Deep sleep was decreased in asthmatics (P = 0.001). In the vigilance test, the mean number of correct answers was lower (P = 0.005) and the mean reaction time was slower (P = 0.002) in asthmatic children. A hierarchical multiple linear regression showed that deep sleep and apnea-hypopnea-related arousal index were significant predictors of vigilance. The data suggest that the prevalence of paediatric sleep-disordered breathing and sleep fragmentation could be very high among children with well-controlled asthma. Moreover, vigilance, the ability to maintain attention and alertness, was worse in stable asthmatic children when compared with healthy controls. Sleep-disordered breathing should be checked even in stable asthmatic children as they are at risk for developing neurobehavioural deterioration associated with frequent arousals during sleep. Furthermore, early treatment for asthma may be required in order to prevent airway remodelling that could cause sleep problems.

Clinical manifestations of respiratory adenoviral infection among hospitalized children in Korea.

BACKGROUND: The objective of our study was to understand the epidemiological and clinical features of respiratory adenoviral infections among children at a single institution over the course of several years. METHODS: From January 2005 to April 2009, 1836 children (≤15 years old) who had been admitted to Korea University Ansan Hospital were tested for acute respiratory infection. The patients who were positive for an adenovirus infection were enrolled in this study, and their medical records were retrospectively reviewed. RESULTS: Adenoviruses were isolated from 310 patients. The male to female ratio was 1.6:1 and mean age was 32 ± 24 months. Children under 5 years of age had the highest prevalence. In 2007, adenovirus infections occurred endemically throughout the year. The clinical diagnoses were primarily upper respiratory tract infections (45.4%), lower respiratory tract infections (48.1%), and neurologic disease (5.2%). Associated symptoms, signs and laboratory findings included fever (91.9%), cough (83.9%), pharyngeal injection (62.3%), rale (32.6%) and elevated C-reactive protein (93.9%). The most common radiologic findings were perihilar and peribronchial infiltrates (42.6%). Co-infections were observed in 29 cases. The mean durations of hospitalization and fever were 6.2 ± 6.5 and 4.8 ± 3.1 days, respectively. The lengths of hospitalization were similar for patients admitted for upper respiratory tract infections with severe morbidity and those admitted for lower respiratory tract infections. No children in the study died. CONCLUSION: Our study demonstrates that respiratory adenovirus infections are an important cause of hospitalization in young children, and contribute to a significant morbidity.

Attention deficit hyperactivity disorder in epileptic children.

It is well-known that the prevalence of attention deficit hyperactivity disorder (ADHD) is higher in epileptic children than in the general pediatric population. The aim of this study was to compare the accompaniment of ADHD in epileptic children with well-controlled seizures and no significant intellectual disability with that in healthy controls. We included epileptic children between the ages of 6 and 12 yr visiting our clinic for six consecutive months and controls without significant medical or psychiatric illnesses. We excluded patients with intellectual disability or persistent seizures during the recent three months. The diagnosis of ADHD was based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV). After exclusion of 84 patients, we enrolled 102 (54.8%) children (mean age, 9.4 ± 2.0 yr). Seven (7 of 102, 6.9%) were diagnosed with ADHD. As compared to control group (4 of 110, 3.6%), there was no difference in ADHD accompaniment (P = 0.29). No difference was observed in ADHD accompaniment according to seizure type and epilepsy syndrome. In conclusion, the accompaniment of ADHD in epileptic children with well-controlled seizures and no intellectual disability may not differ from that of the general pediatric population.

The standard range of peak expiratory flow rates of Korean children.

BACKGROUND: The importance in asthma management of monitoring of peak expiratory flow rate (PEFR) has been emphasized. OBJECTIVE: For effective asthma management in Korean children, we established reference ranges for the PEFR in children 4-18 years of age. METHODS: The Mini Wright Peak Flow Meter (MWPFM) and spirometry were used in this study. All tests were conducted using a standardized method recommended by the American Thoracic Society. RESULTS: From a total sample of 2389 children, 826 (34.5%) were excluded based on our exclusion criteria. For both sexes, the PEFR increased with height, age, weight, sitting height and body surface area (BSA). Height and BSA were found to be better predictors of PEFR than the other parameters. The correlation coefficient between FEV1 and PEFR using the MWPFM was 0.886 (p < .001). The reference values of PEFR for height in our study were higher for both sexes than for those previously reported in Korea (p < .005). When we compared our results with those from other countries, the values for boys of the same height were lower than those for European children, but higher than those for African and Turkish children (p < .001). CONCLUSIONS: We have established reference values for PEFR obtained by MWPFM in Korean children in Seoul, and have provided the percentile curves for PEFR as a function of height asthma to assist clinical practices in treating children with asthma in Korea.

Association between Self-Reported Sleep Duration and Dietary Nutrients in Korean Adolescents: A Population-Based Study.

(1) Background: Adolescence is a transient period from childhood to adulthood, which is characterized by rapid physical growth and psychological changes, including sleep. Because the relationship between insufficient sleep and obesity has been observed in children and adults, the potential links between sleep, dietary intake, and nutrition have received increased attention. We aimed to examine the association of sleep duration with dietary nutrients intake in South Korean adolescents; (2) Methods: This population-based, cross-sectional study analyzed the data obtained from the Korea National Health and Nutrition Examination Survey between 2013 and 2015. Data related to 1422 adolescents aged 12-18 years (741 males and 681 females) were included in the analysis. Sleep duration was assessed using a self-reported questionnaire. Nutrient intake, including daily total energy intake, was assessed with a 24-h dietary recall questionnaire; (3) Results: Most males (84.4%) and females (86.4%) reported < 9 h of sleep per night. Short sleep duration was inversely associated with body mass index and obesity in both sexes. We found that higher intake of fiber and lower intake of sodium were associated with longer sleep duration (P < 0.05). When comparing the intake above and below the estimated average requirements (EAR), the difference in sleep duration was significant in the group that consumed vitamins B1 and C below EAR; (4) Conclusions: The findings of this study indicate that sleep duration can be associated with intake of some nutrients, which may also be associated with obesity in adolescents. Therefore, it is possible to prevent obesity and its complications by controlling the sleep duration and intake of nutrients of adolescents.

Macrolide Resistance and Its Impacts on M. Pneumoniae Pneumonia in Children: Comparison of Two Recent Epidemics in Korea.

PURPOSE: The aim of this study was to investigate the change in macrolide resistance rate in pediatric Mycoplasma pneumoniae pneumonia and to evaluate the influence of macrolide-resistant M. pneumoniae (MRMP) on the clinical course of disease, by comparing 2 recent, consecutive epidemics in Korea. METHODS: A total of 250 patients with M. pneumoniae pneumonia admitted to a single tertiary hospital were enrolled in this study. Detection of MRMP was based on specific point mutations in domain V of the 23S rRNA gene. The medical records of enrolled patients were reviewed retrospectively, and the clinical courses and laboratory data were compared. RESULTS: The macrolide resistance rate of M. pneumoniae was 51.1% (48/94) in the 2011 epidemic, and 87.2% (136/156) in the 2015 epidemic. All MRMP isolates had the A2063G point mutation. In comparison of 2 epidemics, the mean age of patients with M. pneumoniae pneumonia was increased, and the total febrile days and febrile days after initiation of macrolides were prolonged in the 2015 epidemic. Overall severity of MRMP or macrolide-susceptible M. pneumoniae (MSMP) pneumonia over 2 epidemics was not significantly changed. However, the proportion of patients who had a fever lasting more than 72 hours after initiation of macrolides and who received corticosteroid treatment were higher in MRMP pneumonia during 2 epidemics. CONCLUSIONS: The macrolide resistance rate of M. pneumoniae has risen rapidly over 2 recent, consecutive epidemics, and this has been associated with a prolonged clinical course and increased use of corticosteroids to treat pediatric M. pneumoniae pneumonia.

A wearable intravenous infusion device facilitating ambulation: a pre-clinical report.

A wearable ambulatory intravenous infusion device (AIVD) has been developed to facilitate the ambulation of patients. To enhance ambulation, a wearable AIVD was designed and a prototype was developed that consists of an air bag, a reciprocating air pump, a drip rate sensor, and a microprocessor-based controller. Using air pressure as a source for actuation greatly contributes to decreasing the weight of the proposed device and the power consumption. Experimental results show that the proposed infusion device can provide a variety of flow rates ranging from 36-90 mL h(-1) with less than a 10% error. A series of experiments were performed with the prototype of the proposed device at a wide range of flow rates and the results verify that the accuracy and controllability of the prototype is comparable with those of the current intravenous infusion devices available. It is expected that the AIVD significantly contributes to the early recovery of patients by offering a convenient and cost-effective means of ambulation.

Predictive value of C-reactive protein in response to macrolides in children with macrolide-resistant Mycoplasma pneumoniae pneumonia.

PURPOSE: The prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) has increased worldwide. The aim of this study was to estimate the proportion of MRMP in a tertiary hospital in Korea, and to find potential laboratory markers that could be used to predict the efficacy of macrolides in children with MRMP pneumonia. METHODS: A total of 95 patients with M. pneumoniae pneumonia were enrolled in this study. Detection of MRMP was based on the results of specific point mutations in domain V of the 23S rRNA gene. The medical records of these patients were reviewed retrospectively and the clinical course and laboratory data were compared. RESULTS: The proportion of patients with MRMP was 51.6% and all MRMP isolates had the A2063G point mutation. The MRMP group had longer hospital stay and febrile period after initiation of macrolides. The levels of serum C-reactive protein (CRP) and interleukin-18 in nasopharyngeal aspirate were significantly higher in patients who did not respond to macrolide treatment. CRP was the only significant factor in predicting the efficacy of macrolides in patients with MRMP pneumonia. The area under the curve for CRP was 0.69 in receiver operating characteristic curve analysis, indicating reasonable discriminative power, and the optimal cutoff value was 40.7 mg/L. CONCLUSION: The proportion of patients with MRMP was high, suggesting that the prevalence of MRMP is rising rapidly in Korea. Serum CRP could be a useful marker for predicting the efficacy of macrolides and helping clinicians make better clinical decisions in children with MRMP pneumonia.

Mycoplasma pneumoniae associated stroke in a 3-year-old girl.

Infectious diseases precede a significant proportion of acute ischemic strokes in children. Here, we report a case of acute ischemic stroke in a 3-year-old girl with a Mycoplasma pneumonia-associated respiratory tract infection. She developed an acquired prothrombotic state of protein S deficiency and had increased fibrinogen and fibrinogen degradation product levels and increased titer of antinuclear antibodies. However, these conditions were completely alleviated at the 1-month follow-up examination. Infection with M. pneumoniae may cause a transient prothrombotic state that can potentially cause a thrombus.

Periodic leg movement, nasal CPAP, and expiratory muscles.

BACKGROUND: Periodic leg movements (PLMs) may appear during nasal CPAP titration, persisting despite the elimination of hypopneas. METHODS: Systematic recordings of expiratory abdominal muscles on the right and left sides with surface electromyographic (EMG) electrodes lateral to navel, and close from the lateral side of abdomen, were added during nasal CPAP titration for treatment of obstructive sleep apnea (OSA). Positive airway pressure was titrated during nocturnal polysomnography, based on analysis of the flow curve derived from the CPAP equipment and EEG analysis, including persistence of phases A2 and A3 of the cyclic alternating pattern (CAP). The requirement was to eliminate American Association of Sleep Medicine (AASM)-defined hypopnea and also flow limitation and abnormal EEG patterns. When CPAP reached valid results, it was lowered at the time of awakening by 2 or 3 cm H(2)O, and titration was performed again. Data collected during a 7-month period on adults with a prior diagnosis of OSA who had received treatment with nasal CPAP regardless of age and sex were rendered anonymous and were retrospectively rescored by a blinded investigator. RESULTS: Eighty-one successively seen patients with PLMs during CPAP titration were investigated. Elimination of AASM-defined hypopnea was not sufficient to eliminate the PLMs observed during the titration; higher CPAP eliminated flow limitation and CAP phases A2 and A3 and persisting PLMs. PLMs were associated with simultaneous EMG bursts in expiratory abdominal muscles. CONCLUSIONS: The presence of PLMs during CPAP titration indicates the persistence of sleep-disordered breathing. PLMs during CPAP titration are related to the presence of abdominal expiratory muscle activity.

Changes in Major Peanut Allergens Under Different pH Conditions.

Regional dietary habits and cooking methods affect the prevalence of specific food allergies; therefore, we determined the effects of various pH conditions on major peanut allergens. Peanut kernels were soaked overnight in commercial vinegar (pH 2.3) or acetic acid solutions at pH 1.0, 3.0, or 5.0. Protein extracts from the sera of seven patients with peanut-specific IgE levels >15 kU(A)/L were analyzed by SDS-PAGE and immunolabeling. A densitometer was used to quantify and compare the allergenicity of each protein. The density of Ara h 1 was reduced by treatment with pH 1.0, 3.0, or 5.0 acetic acid, or commercial vinegar. Ara h 2 remained largely unchanged after treatment with pH 5.0 acetic acid, and was decreased following treatment with pH 1.0, 2.3, or 3.0 acetic acid. Ara h 3 and Ara h 6 appeared as a thick band after treatment with pH 1.0 acetic acid and commercial vinegar. IgE-binding intensities to Ara h 1, Ara h 2, and Ara h 3 were significantly reduced after treatment with pH 1.0 acetic acid or commercial vinegar. These data suggest that treatment with acetic acid at various pH values affects peanut allergenicity and may explain the low prevalence of peanut allergy in Korea.

Acute tubulointerstitial nephritis following ingestion of Chlorella tablets.

Here, we report on a boy with acute tubulointerstitial nephritis (ATIN), who developed it following ingestion of Chlorella tablets as a food supplement. He was incidentally detected to have glucosuria, proteinuria, and leukocyturia during school mass screening. He had had a history of ingestion of Chlorella tablets for 3 months. Laboratory studies showed anemia, increased levels of creatinine, decreased glomerular filtration rate (GFR), hypokalemia, hypo-uricemia, hypophosphatemia, hypergammaglobulinemia, proteinuria, leukocyturia, and glucosuria. ATIN was diagnosed by renal biopsy. The patient's renal function improved after initiation of corticosteroid therapy and discontinuation of Chlorella for 6 months. Chlorella may be a causative allergen inducing tubulointerstitial injury in kidney.