Sex differences in body composition affect total airway resistance during puberty

Abstract Background During puberty, changes in body composition due to sex hormones are associated with lung mechanics. However, little is known about the mediation effect of sex differences in body composition during puberty with total airway resistance. Methods We prospectively recruited 620 children (10–12years old) from the general population and conducted a cross-sectional study. This study assessed pubertal status according to the five Tanner stages using a questionnaire, line drawings, and each subjects blood sex hormone profile. Both the impulse oscillation system for total lung mechanics and multifrequency bioelectrical impedance for body composition analyses were conducted. The effects of puberty on body composition and subsequent total lung resistance were evaluated using mediation analysis. Results Among the 503 children enrolled, there were 261 males (51.9%) and 242 females (48.1%). In males, higher testosterone levels corresponded with reduced total lung resistance (β = –0.13, 95% CI = –0.21 to –0.05, p < 0.001), and the proportion of the mediating effect through the muscle-fat ratio was 19% (95% CI = 4 to 59, p = 0.02). In contrast, in females, pubertal status reduced total lung resistance (β = –0.27, 95% CI = –0.58 to –0.05, p = 0.04), however, the proportion of the mediating effect through the body mass index was –51% (95% CI = –244 to –4%, p = 0.04). Conclusion The muscle-fat ratio in adolescent males had a synergistic effect with testosterone on improving total airway resistance, whereas improvements in lung resistance by pubertal status were partially masked by body mass index in adolescent females. In conclusion, body composition changes during puberty between males and females have differing effects on total airway resistance

Prevalence and risk factors for vitamin D deficiency in children with iron deficiency anemia

PurposeThe increasing prevalence of breast feeding has led to concerns about vitamin D deficiency (VDD) and iron deficiency anemia (IDA) in children. We evaluated the prevalence of VDD in a population of Korean children with IDA and assessed the risk factors for VDD in these children.MethodsA total of 79 children who were diagnosed with IDA were prospectively surveyed from April 2010 to March 2011. Data were collected by questionnaire, medical assessment, and laboratory tests, including measurement of 25-hydroxyvitamin D (25OHD), hemoglobin, and wrist radiography.ResultsThe median age was 22 months and 30% of the subjects were female. Over a half of subjects (58%) had subnormal vitamin D level (25OHD<30 ng/mL), and VDD (25OHD<20 ng/mL) was present in 39% of children. There was no difference in serum hemoglobin level between IDA patients with VDD and those without VDD. Most subjects (89%) were currently or had recently been breastfed and almost all subjects (97%) who had VDD received breastfeeding. Children with VDD were more likely to be younger than 2 years, to have been breastfed, and to have been tested in winter or spring. Multivariable analysis indicated seasonal variation was a significant independent risk factor for VDD in our IDA patients.ConclusionOur results demonstrated that VDD has a high prevalence in Korean children with IDA. Primary care physicians should be aware of the possibility of VDD in children with IDA and should supplement the vitamin D as well as iron

Nosocomial Outbreak of Carbapenem-Resistant Acinetobacter baumannii in Intensive Care Units and Successful Outbreak Control Program

Acinetobacter baumannii has been increasingly reported as a significant causative organism of various nosocomial infections. Here we describe an outbreak of carbapenem-resistant A. baumannii (CRAB) in the ICUs of a Korean university hospital, along with a successful outbreak control program. From October 2007 through July 2008, CRAB was isolated from 57 ICU patients. Nineteen patients were diagnosed as being truly infected with CRAB, four of whom were presumed to have died due to CRAB infection, producing a case-fatality rate of 21.1%. In surveillance of the environment and the healthcare workers (HCWs), CRAB was isolated from 24 (17.9%) of 135 environmental samples and seven (10.9%) of 65 HCWs. The pulsed field gel electrophoresis patterns showed that the isolates from patients, HCWs, and the environment were genetically related. Control of the outbreak was achieved by enforcing contact precautions, reducing environmental contamination through massive cleaning, and use of a closed-suctioning system. By August 2008 there were no new cases of CRAB in the ICUs. This study shows that the extensive spread of CRAB can happen through HCWs and the environmental contamination, and that proper strategies including strict contact precautions, massive environmental decontamination, and a closed-suctioning system can be effective for controlling CRAB outbreaks

Vitamin D deficiency in Korean children: prevalence, risk factors, and the relationship with parathyroid hormone levels

PurposeThis study was performed to investigate the relationship between serum vitamin D and parathyroid hormone (PTH) levels as well as to describe the prevalence and the risk factors of vitamin D deficiency (VDD) in Korean children.MethodsParticipants were 1,212 children aged 4 to 15 years, who visited Bundang CHA Medical Center (located at 37°N) between March 2012 and February 2013. Overweight was defined as body mass index≥85th percentile. Participants were divided into 4 age groups and 2 seasonal groups. VDD was defined by serum 25-hydroxyvitamin D (25OHD) <20 ng/mL.ResultsThe level of 25OHD was significantly lower in overweight group than in normal weight group (17.1±5.1 ng/mL vs. 19.1±6.1 ng/mL, P<0.001). Winter-spring season (odds ratio [OR], 4.46; 95% confidence interval [CI], 3.45-5.77), older age group (OR, 1.60; 95% CI, 1.36-1.88), and overweight (OR, 2.21; 95% CI, 1.62-3.01) were independently related with VDD. The PTH levels were significantly higher in VDD group compared to vitamin D insufficiency and sufficiency group (P<0.001). In normal weight children, 25OHD (β=-0.007, P<0.001) and ionized calcium (β=-0.594, P=0.007) were independently related with PTH, however, these associations were not significant in overweight children.ConclusionVDD is very common in Korean children and its prevalence increases in winter-spring season, in overweight children and in older age groups. Further investigation on the vitamin D and PTH metabolism according to adiposity is required

Efficacy and safety of tretinoin 0.05% cream to prevent hyperpigmentation during narrowband UV-B phototherapy in patients with facial vitiligo: a randomized clinical trial

Background Narrowband UV-B (NBUVB) phototherapy is the mainstay of vitiligo treatment, but hyperpigmentation is one of the limitations. Meanwhile, topical tretinoin is effective against pigmentary disorders. Objective To determine whether tretinoin 0.05% cream would prevent hyperpigmentation when patients with facial vitiligo underwent phototherapy. Methods A randomized, controlled, split-face trial was conducted. Adult patients with stable, non-segmental facial vitiligo were enrolled. The left/right sides of the face were randomly allocated to receive either topical tretinoin 0.05% cream or moisturizer twice daily. The entire face was subjected to NBUVB phototherapy twice weekly for 12 weeks. The degree of hyperpigmentation was assessed as the delta L* (brightness) value of the darkest spot in each side of the face at baseline and every 4 weeks. The degree of repigmentation was assessed. Results Twenty-five patients were enrolled; 21 completed the study. The delta L* value was significantly different between the two groups: −0.5% in the tretinoin group and −8.7% in the control group at 12 weeks (p = .002). Marked repigmentation was achieved in 15 patients of both groups. Conclusions Tretinoin 0.05% cream prevented hyperpigmentation during NBUVB phototherapy in patients with facial vitiligo, and did not compromise the overall treatment response. Trial registration ClinicalTrials.gov NCT0393377

Korean engineering students??? perceptions of English-medium instruction (EMI) and L1 use in EMI classes

Engineering schools have spearheaded the implementation of English-medium instruction (EMI) in Korean higher education. Three major engineering universities were chosen for this study with its goals to examine engineering students??? perceptions of EMI and L1 use in EMI classes and to make suggestions for the directions that Korean engineering schools should take in relation to EMI. A questionnaire survey was conducted among the undergraduate students of the three universities. Five hundred twenty-four students participated in the survey, and the results show that more students felt insufficient about their English ability than sufficient and that the majority of the students preferred Korean-medium instruction over EMI and did not find EMI beneficial for their English ability. Nevertheless, most of the survey participants believed that EMI should be maintained but with changes in the schools??? mandatory policies. In addition, the students without distinction as to school were supportive of L1 use in EMI classes: approximately 90% of the respondents from each school believed that L1 should be used to facilitate their learning.ope

Delayed diagnosis of 22q11 deletion syndrome due to late onset hypocalcemia in a 11-year-old girl with imperforated anus

Neonatal hypocalcemia and congenital heart defects has been known as the first clinical manifestation of the chromosome 22q11.2 deletion syndrome (22q11DS). However, because of its wide clinical spectrum, diagnosis of 22q11DS can be delayed in children without classic symptoms. We report the case of a girl with the history of imperforate anus but without neonatal hypocalcemia or major cardiac anomaly, who was diagnosed for 22q11DS at the age of 11 after the onset of overt hypocalcemia. She was born uneventfully from phenotypically normal Korean parents. Imperforate anus and partial cleft palate were found at birth, which were surgically repaired thereafter. There was no history of neonatal hypocalcemia, and karyotyping by GTG banding was normal. At the age of 11, hypocalcemia (serum calcium, 5.0 mg/dL) and decreased parathyroid hormone level (10.8 pg/mL) was noted when she visited our Emergency Department for fever and vomiting. The 22q11DS was suspected because of her mild mental retardation and velopharyngeal insufficiency, and a microdeletion on chromosome 22q11.2 was confirmed by fluorescence in situ hybridization. The 22q11DS should be considered in the differential diagnosis of hypocalcemia at any age because of its wide clinical spectrum