Dong-Sung Lee

Clinical features and risk factors for striae distensae in Korean adolescents

Backgroundu2002 Despite the high prevalence of striae distensae, clinical studies are few in number, and their pathophysiology still obscure.

Intense pulsed light vs. pulsed-dye laser in the treatment of facial acne: a randomized split-face trial

Backgroundu2002 Various laser and light therapy have been increasingly used for the treatment of acne vulgaris.

Small RNA changes en route to distinct cellular states of induced pluripotency

MicroRNAs (miRNAs) are critical to somatic cell reprogramming into induced pluripotent stem cells (iPSCs), however, exactly how miRNA expression changes support the transition to pluripotency requires further investigation. Here we use a murine secondary reprogramming system to sample cellular trajectories towards iPSCs or a novel pluripotent F-class state and perform small RNA sequencing. We detect sweeping changes in an early and a late wave, revealing that distinct miRNA milieus characterize alternate states of pluripotency. miRNA isoform expression is common but surprisingly varies little between cell states. Referencing other omic data sets generated in parallel, we find that miRNA expression is changed through transcriptional and post-transcriptional mechanisms. miRNA transcription is commonly regulated by dynamic histone modification, while DNA methylation/demethylation consolidates these changes at multiple loci. Importantly, our results suggest that a novel subset of distinctly expressed miRNAs supports pluripotency in the F-class state, substituting for miRNAs that serve such roles in iPSCs.

Comprehensive genomic analyses associate UGT8 variants with musical ability in a Mongolian population

Background Musical abilities such as recognising music and singing performance serve as means for communication and are instruments in sexual selection. Specific regions of the brain have been found to be activated by musical stimuli, but these have rarely been extended to the discovery of genes and molecules associated with musical ability. Methods A total of 1008 individuals from 73 families were enrolled and a pitch-production accuracy test was applied to determine musical ability. To identify genetic loci and variants that contribute to musical ability, we conducted family-based linkage and association analyses, and incorporated the results with data from exome sequencing and array comparative genomic hybridisation analyses. Results We found significant evidence of linkage at 4q23 with the nearest marker D4S2986 (LOD=3.1), whose supporting interval overlaps a previous study in Finnish families, and identified an intergenic single nucleotide polymorphism (SNP) (rs1251078, p=8.4×10−17) near UGT8, a gene highly expressed in the central nervous system and known to act in brain organisation. In addition, a non-synonymous SNP in UGT8 was revealed to be highly associated with musical ability (rs4148254, p=8.0×10−17), and a 6.2u2005kb copy number loss near UGT8 showed a plausible association with musical ability (p=2.9×10−6). Conclusions This study provides new insight into the genetics of musical ability, exemplifying a methodology to assign functional significance to synonymous and non-coding alleles by integrating multiple experimental methods.

Development of varicella during adalimumab therapy

Editor Adalimumab (Humira®, Abbott Laboratories, Abbott Park, IL, USA) is a fully humanized recombinant anti-TNF (tumour necrosis factor)-α monoclonal antibody. We describe the development of varicella with hepatic involvement in a patient who was receiving adalimumab for rheumatoid arthritis (RA). A 42-year-old Korean woman with a 15-year history of RA presented with a 4-day history of generalized vesicles. She had received adalimumab 40 mg as a subcutaneous injection biweekly for 70 weeks, in addition to methotrexate 15 mg/week, deflazacort 6 mg/day, folate, omeprazole, aspirin microcoated, and amlodipine besylate (Norvasc®, Pfizer Inc., New York, NY, USA). She complained of general weakness, myalgia, anorexia, sore throat, and abdominal pain. Tenderness on the left upper quadrant was present with slightly increased bowel sound. She was normotensive and had a body temperature of 36.9 °C (98.4 °F). Skin examination revealed generalized, scattered, various-sized, tense, umbilicated vesicles and erosions on the scalp, face, neck, trunk, both inner thighs, and both upper arms (fig. 1a). She was reported to have suffered from chickenpox during childhood and denied recent close contact with any patient suspected of having chickenpox. Laboratory tests were within normal ranges except for aspartate aminotransferase (AST) 201 IU/L (normal values ≤ 40 IU/L), alanine aminotransferase (ALT) 153 IU/L (normal values ≤ 40 IU/L), both of which were previously normal. Antibodies for hepatitis A, B, C viruses, human immunodeficiency virus, and smooth muscle antigen were negative. Ceruloplasmin was within the normal range. Chest radiograph was normal and abdominal film revealed mild ileus. Multinucleated giant cells were seen in Tzanck’s smear preparation and skin biopsy showed multiloculated, intraepidermal vesicle formation, and reticular degeneration of epidermis with multinucleated keratinocytes (fig. 1b). Vesicular fluid showed a positively amplified band for varicella zoster virus (VZV) but no band for herpes simplex virus (HSV) on polymerase chain reaction (PCR) (fig. 1c). Varicella titres were negative for both IgM and IgG. Although intravenous acyclovir had been initiated, pruritic vesicles continued to develop, and AST and ALT reached up to

Risk factors associated with human papillomavirus infection status in a Korean cohort.

By surveying extensive epidemiological behavioural and sexual risk factors in a Korean twin cohort, risk factors for human papillomavirus (HPV) infection were investigated in South Korea. A total of 912 vaginal specimens were collected from the Healthy Twin Study, consisting of twins and their families. A range of epidemiological, behavioural, and sexual activity characteristics were evaluated using multivariate logistic regression analyses of family and twin relationships, adjusted to elucidate the risk factors for HPV infection. Of the various epidemiological characteristics, the possibility of extramarital affairs [odds ratio (OR) 2·48, 95% confidence interval (CI) 1·02-6·02] significantly increased the prevalence of HPV infection. Our multivariate regression analysis indicated that oral contraceptive use (OR 40·64, 95% CI 0·99-1670·7) and history of sexually transmitted disease (OR 2·56, 95% CI 0·93-7·10) were strongly associated with an increase in HPV infection. On the other hand, more frequent vaginal douching (OR 0·32, 95% CI 0·13-0·77) significantly decreased the prevalence of HPV infection. Our results suggested that HPV infection is associated with both biological and behavioural factors.

A copy number variation in PKD1L2 is associated with colorectal cancer predisposition in korean population.

Recently reported genome‐wide association studies have identified more than 20 common low‐penetrance colorectal cancer (CRC) susceptibility loci. Recent studies have reported that copy number variations (CNVs) are considered important human genomic variants related to cancer, while the contribution of CNVs remains unclear. We performed array comparative genomic hybridization (aCGH) in 36 CRC patients and 47 controls. Using breakpoint PCR, we confirmed the breakpoint of the PKD1L2 deletion region. High frequency of PKD1L2 CNV was observed in CRC cases. We validated the association between PKD1L2 variation and CRC risk in 1,874 cases and 2,088 controls (ORu2009=u20091.44, 95% CIu2009=u20091.04–1.98, pu2009=u20090.028). Additionally, PKD1L2 CNV is associated with increased CRC risk in patients younger than 50 years (ORu2009=u20092.14, 95% CI 1.39–3.30, pu2009=u20095.8 × 10−4). In subgroup analysis according to body mass index (BMI), we found that the CN loss of PKD1L2 with BMI above or equal to 25 exhibited a significant increase in CRC risk (ORu2009=u20092.29, 95% CI 1.29–4.05, pu2009=u20090.005). PKD1L2 CNV with BMI above or equal to 25 and age below 50 is associated with a remarkably increased risk of colorectal cancer (ORu2009=u20095.24, 95% CI 2.36–11.64, p= 4.8 × 10−5). Moreover, we found that PKD1L2 variation in obese patients (BMIu2009≥u200925) was associated with poor survival rate (pu2009=u20090.026). Our results suggest that the common PKD1L2 CNV is associated with CRC, and PKD1L2 CNV with high BMI and/or age below 50 exhibited a significant increased risk of CRC. In obese patients, PKD1L2 variation was associated with poor survival.

Erratum: Corrigendum: Genome-wide characterization of the routes to pluripotency

This corrects the article DOI: 10.1038/nature14046

Corrigendum: Genome-wide characterization of the routes to pluripotency

This corrects the article DOI: 10.1038/nature14046