The practical use of graphene in consumer electronics has not been demonstrated since the size, uniformity, and reliability problems are yet to be solved to satisfy industrial standards. Here we ...report mass-produced graphene films synthesized by hydrogen-free rapid thermal chemical vapor deposition (RT-CVD), roll-to-roll etching, and transfer methods, which enabled faster and larger production of homogeneous graphene films over 400 × 300 mm2 area with a sheet resistance of 249 ± 17 Ω/sq without additional doping. The properties of RT-CVD graphene have been carefully characterized by high-resolution transmission electron microscopy, Raman spectroscopy, chemical grain boundary analysis, and various electrical device measurements, showing excellent uniformity and stability. In particular, we found no significant correlation between graphene domain sizes and electrical conductivity, unlike previous theoretical expectations for nanoscale graphene domains. Finally, the actual application of the RT-CVD films to capacitive multitouch devices installed in the most sophisticated mobile phone was demonstrated.
Whole-exome sequencing (WES) has become a standard method for detecting genetic variants in human diseases. Although the primary use of WES data has been the identification of single nucleotide ...variations and indels, these data also offer a possibility of detecting copy number variations (CNVs) at high resolution. However, WES data have uneven read coverage along the genome owing to the target capture step, and the development of a robust WES-based CNV tool is challenging. Here, we evaluate six WES somatic CNV detection tools: ADTEx, CONTRA, Control-FREEC, EXCAVATOR, ExomeCNV and Varscan2. Using WES data from 50 kidney chromophobe, 50 bladder urothelial carcinoma, and 50 stomach adenocarcinoma patients from The Cancer Genome Atlas, we compared the CNV calls from the six tools with a reference CNV set that was identified by both single nucleotide polymorphism array 6.0 and whole-genome sequencing data. We found that these algorithms gave highly variable results: visual inspection reveals significant differences between the WES-based segmentation profiles and the reference profile, as well as among the WES-based profiles. Using a 50% overlap criterion, 13-77% of WES CNV calls were covered by CNVs from the reference set, up to 21% of the copy gains were called as losses or vice versa, and dramatic differences in CNV sizes and CNV numbers were observed. Overall, ADTEx and EXCAVATOR had the best performance with relatively high precision and sensitivity. We suggest that the current algorithms for somatic CNV detection from WES data are limited in their performance and that more robust algorithms are needed.
We performed targeted re-sequencing to identify the genetic etiology of early-onset postlingual deafness and encountered a frequent
allele harboring two variants in a cis configuration. We aimed to ...evaluate the pathogenicity of the allele. Among 88 cochlear implantees with autosomal recessive non-syndromic hearing loss, subjects with
and
mutations were excluded. Thirty-one probands manifesting early-onset postlingual deafness were sorted. Through targeted re-sequencing, we detected two families with a
mutant allele containing p.V116M and p.V291L in a cis configuration, p.p.V116M; p.V291L. A minor allele frequency was calculated and proteolytic activity was measured. A p.p.V116M; p.V291L allele demonstrated a significantly higher frequency compared to normal controls and merited attention due to its high frequency (4.84%, 3/62). The first family showed a novel deleterious splice site variant-c.783-1G>A-in a trans allele, while the other showed homozygosity. The progression to deafness was noted within the first decade, suggesting DFNB10. The proteolytic activity was significantly reduced, confirming the severe pathogenicity. This frequent mutant allele significantly contributes to early-onset postlingual deafness in Koreans. For clinical implication and proper auditory rehabilitation, it is important to pay attention to this allele with a severe pathogenic potential.
Autosomal dominant polycystic kidney disease (ADPKD) is one of the main causes of end-stage renal disease (ESRD). Genetic information is of the utmost importance in understanding pathogenesis of ...ADPKD. Therefore, this study aimed to demonstrate the genetic characteristics of ADPKD and their effects on renal function in 749 Korean ADPKD subjects from 524 unrelated families. Genetic studies of PKD1/2 were performed using targeted exome sequencing combined with Sanger sequencing in exon 1 of the PKD1 gene and a multiple ligation probe assay. The mutation detection rate was 80.7% (423/524 families, 331 mutations) and 70.7% was novel. PKD1 protein-truncating (PKD1-PT) genotype was associated with younger age at diagnosis, larger kidney volume, lower renal function compared to PKD1 non-truncating and PKD2 genotypes. The PKD1 genotype showed earlier onset of ESRD compared to PKD2 genotype (64.9 vs. 72.9 years old, P < 0.001). In frailty model controlled for age, gender, and familial clustering effect, PKD2 genotype had 0.2 times lower risk for reaching ESRD than PKD1-PT genotype (p = 0.037). In conclusion, our results suggest that genotyping can contribute to selecting rapid progressors for new emerging therapeutic interventions among Koreans.
Hereditary cerebellar ataxias exhibit heterogeneous phenotypes and genotypes. To date, advancement of next-generation sequencing technologies have identified many causative genes for ataxia in ...various population. In this study, whole-exome sequencing (WES) was utilized to explore the genetic cause of ataxia among Korean patients who remained undiagnosed following routine investigation.
Patients with ataxia were enrolled in this study. We excluded patients with acquired, degenerative, and trinucleotide repeat ataxias, such as spinocerebellar ataxia 1 (SCA1), SCA2, SCA3, SCA6, SCA7, SCA8, SCA17, Dentatorubral-pallidoluysian atrophy, and Friedreich ataxia. WES was performed. After basic filtering based on population databases, we then performed primary filtering to screen for known ataxia-associated genes, followed by expanded filtering customized for individual patients.
We enrolled 77 ataxia patients from 68 families. Eighteen families had pathogenic or likely pathogenic variants in 14 different genes, including NEU1, APTX, SPG7, HTRA1, POLG2, SYNE1, CACNA1G, CACNA1A, ITPR1, AHI1, SPG11, ANO10, ATM, and C5orf42, resulting in a diagnostic yield of 26.5%. Hereditary spastic paraplegia was the most common diagnosis. Adult-onset ataxias and those without family history were frequently encountered. Variants of unknown significance were found in 14 (20.6%) families, some of which were highly probable from the clinical perspective.
Using WES, we explored the molecular etiology of ataxia in patients whom were not diagnosed through routine clinical investigation. This study revealed unexpected rare disorders as well as the known ataxia-associated genes in a Korean population.
•Diagnosis of hereditary ataxias is challenging because of heterogeneous phenotypes.•WES was performed in Korean ataxic patients, resulting in a 26.5% diagnostic yield.•We found unexpected rare disorders as well as the known ataxia-associated genes.•Hereditary spastic paraplegia was the most common diagnosis.•These may assist the identification of the roles of VUS in future studies.
We aimed to evaluate associations between the ratio of serum estrone (E1) to estradiol (E2) and parameters related to serum glucose metabolism and insulin resistance in women with polycystic ovary ...syndrome (PCOS).
In total, 133 women between the ages of 18 and 35 diagnosed with PCOS were enrolled in this study. All participants with PCOS underwent blood tests to determine hormonal and biochemical metabolic parameters and a standard 2-hour 75-g oral glucose tolerance test. They were divided into two groups according to the serum E1-to-E2 ratio: group 1 (E1/E2 ratio <2.0) and group 2 (E1/E2 ratio ≥2.0).
In the comparative analysis, the waist-to-hip ratio (WHR) was the only clinical variable that was significantly different between the two groups. Patients with a higher E1/E2 ratio showed higher fasting insulin levels, homeostasis model for insulin resistance, and postprandial glucose level at 2 hours (PPG2). In a correlation analysis, only PPG2 was significantly related to the serum E1/E2 ratio. However, after controlling for the confounding effects of body mass index (BMI) and WHR, fasting glucose was also significantly correlated with the serum E1/E2 ratio.
Women with PCOS with a higher serum E1/E2 ratio were found to be more likely to show higher fasting insulin and postprandial glucose levels. Significant correlations were found between the serum E1/E2 ratio and both fasting and postprandial serum glucose levels after adjusting for BMI and WHR in women with PCOS.
Epidemiologic findings of low-volume alcohol consumption in relation to gastrointestinal cancers including gastric cancer are inconsistent.
The association between alcohol intake and esophageal, ...gastric and colorectal cancer risk was examined in a population-based prospective cohort of 23,323,730 adults in Korea who had undergone a biennial evaluation provided by the National Health Insurance Corporation between the years 2009 and 2012. After median 5.4 years of follow-up, 9,171 esophageal, 135,382 gastric and 154,970 colorectal cancer cases were identified. Cox regression models were used to estimate hazard ratios (HR) and corresponding 95% confidence intervals (95% CI).
Light drinking as well as moderate to heavy alcohol consumption significantly increased the risks of the three gastrointestinal cancers (HR 1.51; 95% CI, 1.43-1.60; HR 1.08; 95% CI, 1.06-1.09; HR 1.12; 95% CI, 1.11-1.14) compared with non-drinkers after adjusting for age, sex, smoking, exercise, income, body mass index, and diabetes. The synergistically increased cancer risk between excessive amount of alcohol consumption and currently smoking or underweight individuals was observed only in the esophageal cancers.
Light drinking including even one alcoholic drink a day is associated with increased risks of esophageal, gastric and colorectal cancer.
This study aimed to characterize the changes in the gut microbiota of irritable bowel syndrome (IBS) patients and to investigate the consequent alterations in bacterial functions.
We performed 16S ...rRNA metagenomic sequencing and a phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analyses using fecal samples from control (n=12) and diarrhea-dominant IBS patients (n=7).
The samples were clustered by the principal coordinates analysis depending on the presence of IBS (p=0.003). In the IBS patients, the abundances of Acidaminococcaceae, Sutterellaceae, and Desulfovibrionaceae were significantly increased, while those of Enterococcaceae, Leuconostocaceae, Clostridiaceae, Peptostreptococcaceae, and Lachnospiraceae were significantly decreased. The PICRUSt results indicated that two orthologues involved in secondary bile acid biosynthesis were significantly decreased in IBS patients. Modules involved in multidrug resistance, lipopolysaccharide biosynthesis, the reductive citrate cycle, and the citrate cycle were significantly increased in the IBS patients. In contrast, modules involved in cationic antimicrobial peptide resistance, and some transport systems were more abundant in controls than in IBS patients.
Changes in the gut microbiota composition in IBS patients lead to alterations in bacterial functions, such as bile acid transformation and the induction of inflammation, which is a known pathophysiological mechanism of IBS.
Background
Nephronophthisis 13 (NPHP 13) is associated with mutations in the
WDR19
gene, which encodes for a protein in the intraflagellar transport complex. Herein, we describe six additional cases ...accompanied by Caroli syndrome or disease.
Methods
Targeted exome sequencing covering 96 ciliopathy-related genes was performed for 48 unrelated Korean patients with a clinical suspicion of NPHP. Mutations were confirmed by Sanger sequencing. We evaluated the expression of WDR19 in the biopsied kidney by immunohistochemistry in patients and controls.
Results
We detected three (3/48, 6.3 %) unrelated index cases with
WDR19
mutations. One of the cases involved two siblings with the same mutation. Later, we detected an additional index case with a similar phenotype of kidney and liver involvement by Sanger sequencing of
WDR19
. The p.R1178Q mutation was common in all patients. All of the six affected patients from four families progressed to chronic kidney disease. Of note, all six patients had Caroli syndrome or disease. Immunohistochemistry for WDR19 showed localized expression along the luminal borders of the renal tubular epithelium in controls, whereas it showed diffuse cytoplasmic staining in the affected patients.
Conclusions
Caroli disease is a major extra-renal phenotype associated with mutations in
WDR19
in the Korean population. In this study, we visually validated the expression pattern of mutant WDR19 protein in the kidneys of NPHP 13 patients. More data are needed to identify the true frequency of p.R1178Q. Functional studies including transfection assay will provide solid grounds for the pathogenicity of each mutation.
Steroid-resistant nephrotic syndrome (SRNS) is one of the major causes of end-stage renal disease (ESRD) in childhood and is mostly associated with focal segmental glomerulosclerosis (FSGS). More ...than 50 monogenic causes of SRNS or FSGS have been identified. Recently, the mutation detection rate in pediatric patients with SRNS has been reported to be approximately 30%. In this study, genotype-phenotype correlations in a cohort of 291 Korean pediatric patients with SRNS/FSGS were analyzed. The overall mutation detection rate was 43.6% (127 of 291 patients).
was the most common causative gene (23.6%), followed by
(9.4%),
(8.7%),
(7.1%), and
(6.3%). Mutations in
,
, and
were more frequently detected, and mutations in
were less commonly detected in this cohort than in study cohorts from Western countries. The mutation detection rate was higher in patients with congenital onset, those who presented with proteinuria or chronic kidney disease/ESRD, and those who did not receive steroid treatment. Genetic diagnosis in patients with SRNS provides not only definitive diagnosis but also valuable information for decisions on treatment policy and prediction of prognosis. Therefore, further genotype-phenotype correlation studies are required.