Transethnic analysis of the human leukocyte antigen region for ulcerative colitis reveals not only shared but also ethnicity-specific disease associations.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gut. Genetic association studies have identified the highly variable human leukocyte antigen (HLA) region as the strongest susceptibility locus for IBD and specifically DRB1*01:03 as a determining factor for ulcerative colitis (UC). However, for most of the association signal such as delineation could not be made because of tight structures of linkage disequilibrium within the HLA. The aim of this study was therefore to further characterize the HLA signal using a transethnic approach. We performed a comprehensive fine mapping of single HLA alleles in UC in a cohort of 9272 individuals with African American, East Asian, Puerto Rican, Indian and Iranian descent and 40 691 previously analyzed Caucasians, additionally analyzing whole HLA haplotypes. We computationally characterized the binding of associated HLA alleles to human self-peptides and analyzed the physicochemical properties of the HLA proteins and predicted self-peptidomes. Highlighting alleles of the HLA-DRB1*15 group and their correlated HLA-DQ-DR haplotypes, we not only identified consistent associations (regarding effects directions/magnitudes) across different ethnicities but also identified population-specific signals (regarding differences in allele frequencies). We observed that DRB1*01:03 is mostly present in individuals of Western European descent and hardly present in non-Caucasian individuals. We found peptides predicted to bind to risk HLA alleles to be rich in positively charged amino acids. We conclude that the HLA plays an important role for UC susceptibility across different ethnicities. This research further implicates specific features of peptides that are predicted to bind risk and protective HLA proteins.

Clinical importance of weight gain and associated factors in patients with moderate to severe ulcerative colitis: results from the MOSAIK cohort in Korea.

BACKGROUND: Many patients with ulcerative colitis (UC) gain weight after treatment. However, the clinical significance of weight gain in these patients remains unclear. This study aimed to evaluate body weight changes after treatment in patients newly diagnosed with moderate-to-severe UC and their effects on patients' prognosis. METHODS: The change in weight between diagnosis and 1 year after treatment in 212 patients enrolled in the MOSAIK cohort (mean age, 40 years; males, 60%) was analyzed. Significant weight gain was defined as a weight increase of ≥ 5% from the baseline at 1 year. Factors associated with significant weight gain and the effect of significant weight gain on the risk of major adverse outcomes (clinical relapse, hospitalization, and new use of steroids or biologics) during a follow-up period of 20 months were evaluated. RESULTS: Mean weight gain at 1 year was 1.7 ± 4.2 kg. The proportion of overweight/obese patients increased by 9.0% from 37.9% to 46.9%. Thirty-two percent had significant weight gain; extensive colitis at diagnosis was the only factor associated with significant weight gain (odds ratio 6.5, 95% confidence interval 1.4-31.0, p = 0.006). In multivariable analysis, significant weight gain was not associated with the risk of major adverse outcomes. Weight loss symptoms at diagnosis were associated with an increased risk for new steroid use after 1 year. CONCLUSIONS: Approximately one-third of patients with moderate-to-severe UC had significant weight gain after 1 year of treatment. However, significant weight gain was not associated with the patient's prognosis.

Construction and benchmarking of a multi-ethnic reference panel for the imputation of HLA class I and II alleles.

Genotype imputation of the human leukocyte antigen (HLA) region is a cost-effective means to infer classical HLA alleles from inexpensive and dense SNP array data. In the research setting, imputation helps avoid costs for wet lab-based HLA typing and thus renders association analyses of the HLA in large cohorts feasible. Yet, most HLA imputation reference panels target Caucasian ethnicities and multi-ethnic panels are scarce. We compiled a high-quality multi-ethnic reference panel based on genotypes measured with Illumina's Immunochip genotyping array and HLA types established using a high-resolution next generation sequencing approach. Our reference panel includes more than 1,300 samples from Germany, Malta, China, India, Iran, Japan and Korea and samples of African American ancestry for all classical HLA class I and II alleles including HLA-DRB3/4/5. Applying extensive cross-validation, we benchmarked the imputation using the HLA imputation tool HIBAG, our multi-ethnic reference and an independent, previously published data set compiled of subpopulations of the 1000 Genomes project. We achieved average imputation accuracies higher than 0.924 for the commonly studied HLA-A, -B, -C, -DQB1 and -DRB1 genes across all ethnicities. We investigated allele-specific imputation challenges in regard to geographic origin of the samples using sensitivity and specificity measurements as well as allele frequencies and identified HLA alleles that are challenging to impute for each of the populations separately. In conclusion, our new multi-ethnic reference data set allows for high resolution HLA imputation of genotypes at all classical HLA class I and II genes including the HLA-DRB3/4/5 loci based on diverse ancestry populations.

Effect of Nonsteroidal Anti-inflammatory Agents on Small Intestinal Injuries as Evaluated by Capsule Endoscopy.

BACKGROUND: Currently, because the population is aging, use of medications has been increasing, including use of nonsteroidal anti-inflammatory drugs (NSAIDs) and antithrombotic agents. AIMS: This study aims to investigate whether NSAIDs can cause damage to the small bowel (SB) mucosa. METHODS: Endoscopic videos of subjects who had undergone capsule endoscopy (CE) were evaluated by three experts in order to identify SB injury. All medications taken within 2 weeks from the time of CE were investigated. Cases with a final diagnosis of intestinal tuberculosis, inflammatory bowel disease, Behcet's disease, Peutz-Jeghers syndrome, small bowel lymphoma, or Henoch-Schönlein purpura were excluded from the analysis. RESULTS: Among the 273 subjects, 125 (45.8%) had SB erosions or ulcers (erosion group) and the remaining 148 (54.2%) did not (no erosion group). SB erosions or ulcers were more common in females, patients aged > 60 years, and subjects taking NSAIDs (p = 0.048, 0.032, and < 0.001, respectively). No statistically significant differences were found between the two groups in the following variables: history of cancer and GI surgery, reasons for the test, comorbidities, and use of anticoagulants and antiplatelet agents. Multivariate analysis showed that use of NSAIDs [OR 4.191 (95% CI 1.858-9.458), p < 0.001] was an independent risk factor for SB erosions or ulcers. CONCLUSIONS: Use of NSAIDs is the only independent risk factor for SB injury identified in this study. Antithrombotic agents do not cause or exacerbate damage to the SB, according to our results. CLINICAL TRIAL REGISTRATION: KCT0004795.

Protein-coding variants contribute to the risk of atopic dermatitis and skin-specific gene expression.

BACKGROUND: Fifteen percent of atopic dermatitis (AD) liability-scale heritability could be attributed to 31 susceptibility loci identified by using genome-wide association studies, with only 3 of them (IL13, IL-6 receptor [IL6R], and filaggrin [FLG]) resolved to protein-coding variants. OBJECTIVE: We examined whether a significant portion of unexplained AD heritability is further explained by low-frequency and rare variants in the gene-coding sequence. METHODS: We evaluated common, low-frequency, and rare protein-coding variants using exome chip and replication genotype data of 15,574 patients and 377,839 control subjects combined with whole-transcriptome data on lesional, nonlesional, and healthy skin samples of 27 patients and 38 control subjects. RESULTS: An additional 12.56% (SE, 0.74%) of AD heritability is explained by rare protein-coding variation. We identified docking protein 2 (DOK2) and CD200 receptor 1 (CD200R1) as novel genome-wide significant susceptibility genes. Rare coding variants associated with AD are further enriched in 5 genes (IL-4 receptor [IL4R], IL13, Janus kinase 1 [JAK1], JAK2, and tyrosine kinase 2 [TYK2]) of the IL13 pathway, all of which are targets for novel systemic AD therapeutics. Multiomics-based network and RNA sequencing analysis revealed DOK2 as a central hub interacting with, among others, CD200R1, IL6R, and signal transducer and activator of transcription 3 (STAT3). Multitissue gene expression profile analysis for 53 tissue types from the Genotype-Tissue Expression project showed that disease-associated protein-coding variants exert their greatest effect in skin tissues. CONCLUSION: Our discoveries highlight a major role of rare coding variants in AD acting independently of common variants. Further extensive functional studies are required to detect all potential causal variants and to specify the contribution of the novel susceptibility genes DOK2 and CD200R1 to overall disease susceptibility.

Genotype-based Treatment With Thiopurine Reduces Incidence of Myelosuppression in Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Thiopurine-related myelosuppression (most frequently leukopenia) interferes with thiopurine therapy for patients with inflammatory bowel diseases (IBD). We investigated whether pretreatment analyses genetic variants associated with thiopurine-induced leukopenia could be used to effectively identify patients who required dose adjustments. METHODS: We performed a multicenter, prospective study of patients with IBD at 5 tertiary medical centers in Korea, from January 2016 through September 2018. Seventy-two patients were randomly assigned to a group that underwent genotype analysis for the NUDT15 variant (rs116855232) and FTO variant (rs79206939) and 3 common TPMT variants (rs1800460, rs1800462, rs1142345) associated with myelosuppression and 92 patients were assigned to a group that did not undergo genotype analysis (non-genotyping group). Patients heterozygous for any variant received 50 mg azathioprine equivalents, whereas those who were homozygous for any variant received alternative drugs. Patients who did not carry any of the genetic variants and patients in the non-genotyping group received 50 mg azathioprine equivalents followed by dose escalation up to 2-2.5 mg/kg. Myelosuppression was defined as white blood cell counts below 3000/µL, levels of hemoglobin 10 g/dL, or platelet counts below 100 K/µL. RESULTS: Twelve patients (16.7%) in the genotype analysis group and 33 patients (35.9%) in the non-genotyping group developed myelosuppression (P=.005). A multivariate analysis revealed that body mass indices above 21 kg/m2 (hazard ratio [HR], 0.43; 95% CI, 0.22-0.81; P = .009), pretreatment genotype analysis (HR, 0.37; 95% CI, 0.18-0.77; P = .008), and the maximum dose of thiopurines (HR, 0.34; 95% CI, 0.19-0.59; P < .001) independently decreased risk of myelosuppression. Pretreatment genotype analysis reduced numbers of outpatient clinic visit and numbers of patients with drug discontinuation or dose reductions. CONCLUSIONS: In a randomized controlled study of patients undergoing thiopurine therapy for IBD, we found that selection of therapy based on genetic variants associated with thiopurine-induced leukopenia significantly reduced the proportion of patients with myelosuppression during treatment. ClinicalTrials.gov no: NCT03719118.

The Protective Effect of 5-Aminosalicylic Acid Against Non-Steroidal Anti-Inflammatory Drug-Induced Injury Through Free Radical Scavenging in Small Intestinal Epithelial Cells.

Background and objectives: Non-steroidal anti-inflammatory drugs (NSAIDs) have been among the major causes of small intestinal injury in clinical practice. As such, the current study investigated the protective effect of 5-aminosalicylic acid (5-ASA) against an NSAID-induced small intestinal injury. Materials and Methods: IEC-6 cells were treated with various concentrations of indomethacin with or without 5-ASA in a serum-free medium, after which an 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Dromide (MTT) assay, a cell apoptosis assay, a caspase-3 activity assay, a reactive oxygen species (ROS) content and Superoxide dismutase 2 (SOD2) activity measurement, a Western blotting for occludin and zonula occludens-1 (ZO-1) and a wound healing assay were conducted. Results: 5-ASA ameliorated indomethacin-induced cell apoptosis and an increase in the intracellular ROS content while augmenting the indomethacin-induced suppression of SOD2 activity in IEC-6 cells. Moreover, 5-ASA reversed the indomethacin-induced attenuation of occludin and ZO-1 expression and promoted faster wound healing effects in IEC-6 cells following an indomethacin-induced injury. Conclusion: Our results suggested that 5-ASA protects small intestinal cells against an NSAID-induced small intestinal injury by scavenging free radicals. Therefore, 5-ASA could be a potential treatment for an NSAID-induced small intestinal injury.

ZNF133 is associated with infliximab responsiveness in patients with inflammatory bowel diseases.

BACKGROUND AND AIM: Infliximab has been widely prescribed for treating inflammatory bowel disease (IBD). However, the response rates to infliximab differ among patients. Therefore, we aimed to identify the genetic and clinical markers that predict infliximab response. METHODS: A total of 139 Korean patients with IBD who received infliximab were classified according to infliximab response as follows: (i) primary response vs nonresponse and (ii) sustained response vs loss of response. We performed an association study using whole-exome sequencing data to identify genetic variants associated with infliximab response. Candidate variants were validated in 77 German patients with IBD. Stepwise multivariate logistic regression was performed to identify predictors. RESULTS: We found five candidate variants that were associated with primary nonresponse to infliximab (P < 5 × 10-6 ). Of the five variants, rs2228273 in ZNF133 was validated in German (combined P = 6.49 × 10-7 ). We also identified the best genetic variant (rs9144, P = 4.60 × 10-6 ) associated with the loss of infliximab response. In multivariate regression analysis, rs2228273 (P = 2.10 × 10-5 ), concurrent azathioprine/6-mercaptopurine use, and bodyweight at the first infliximab use (< 50 kg) were associated with primary nonresponse. In addition, the Crohn's disease activity index at the first infliximab use and rs9144 (P = 0.001) were independently associated with the loss of response in patients with Crohn's disease. CONCLUSIONS: We identified clinical and genetic markers associated with infliximab response in IBD patients. Our findings could provide insights to maximize the efficacy of infliximab therapy in IBD patients.

Autistic-like social behaviour in Shank2-mutant mice improved by restoring NMDA receptor function.

Autism spectrum disorder (ASD) is a group of conditions characterized by impaired social interaction and communication, and restricted and repetitive behaviours. ASD is a highly heritable disorder involving various genetic determinants. Shank2 (also known as ProSAP1) is a multi-domain scaffolding protein and signalling adaptor enriched at excitatory neuronal synapses, and mutations in the human SHANK2 gene have recently been associated with ASD and intellectual disability. Although ASD-associated genes are being increasingly identified and studied using various approaches, including mouse genetics, further efforts are required to delineate important causal mechanisms with the potential for therapeutic application. Here we show that Shank2-mutant (Shank2(-/-)) mice carrying a mutation identical to the ASD-associated microdeletion in the human SHANK2 gene exhibit ASD-like behaviours including reduced social interaction, reduced social communication by ultrasonic vocalizations, and repetitive jumping. These mice show a marked decrease in NMDA (N-methyl-D-aspartate) glutamate receptor (NMDAR) function. Direct stimulation of NMDARs with D-cycloserine, a partial agonist of NMDARs, normalizes NMDAR function and improves social interaction in Shank2(-/-) mice. Furthermore, treatment of Shank2(-/-) mice with a positive allosteric modulator of metabotropic glutamate receptor 5 (mGluR5), which enhances NMDAR function via mGluR5 activation, also normalizes NMDAR function and markedly enhances social interaction. These results suggest that reduced NMDAR function may contribute to the development of ASD-like phenotypes in Shank2(-/-) mice, and mGluR modulation of NMDARs offers a potential strategy to treat ASD.

A coding variant in FTO confers susceptibility to thiopurine-induced leukopenia in East Asian patients with IBD.

OBJECTIVE: Myelosuppression is a life-threatening complication of thiopurine therapy, and the incidence of thiopurine-induced myelosuppression is higher in East Asians than in Europeans. We investigated genetic factors associated with thiopurine-induced leukopenia in patients with IBD. DESIGN: A genome-wide association study (GWAS) was conducted in thiopurine-treated patients with IBD, followed by high-throughput sequencing of genes identified as significant in the GWAS or those involved in thiopurine metabolism (n=331). Significant loci associated with thiopurine-induced leukopenia were validated in two additional replication cohorts (n=437 and n=330). Functional consequences of FTO (fat mass and obesity-associated) variant were examined both in vitro and in vivo. RESULTS: The GWAS identified two loci associated with thiopurine-induced leukopenia (rs16957920, FTO intron; rs2834826, RUNX1 intergenic). High-throughput targeted sequencing indicated that an FTO coding variant (rs79206939, p.A134T) linked to rs16957920 is associated with thiopurine-induced leukopenia. This result was further validated in two replication cohorts (combined p=1.3×10-8, OR=4.3). The frequency of FTO p.A134T is 5.1% in Koreans but less than 0.1% in Western populations. The p.A134T variation reduced FTO activity by 65% in the nucleotide demethylase assay. In vivo experiments revealed that Fto-/- and Fto+/- mice were more susceptible to thiopurine-induced myelosuppression than wild-type mice. CONCLUSIONS: The results suggest that the hypomorphic FTO p.A134T variant is associated with thiopurine-induced leukopenia. These results shed light on the novel physiological role of FTO and provide a potential pharmacogenetic biomarker for thiopurine therapy.

Association study between OCTN1 functional haplotypes and Crohn's disease in a Korean population.

Crohn's disease (CD) is a chronic inflammatory bowel disease with multifactorial causes including environmental and genetic factors. Several studies have demonstrated that the organic cation/carnitine transporter 1 (OCTN1) non-synonymous variant L503F is associated with susceptibility to CD. However, it was reported that L503F is absent in Asian populations. Previously, we identified and functionally characterized genetic variants of the OCTN1 promoter region in Koreans. In that study, four variants demonstrated significant changes in promoter activity. In the present study, we determined whether four functional variants of the OCTN1 promoter play a role in the susceptibility to or clinical course of CD in Koreans. To examine it, the frequencies of the four variants of the OCTN1 promoter were determined by genotyping using DNA samples from 194 patients with CD and 287 healthy controls. Then, associations between genetic variants and the susceptibility to CD or clinical course of CD were evaluated. We found that susceptibility to CD was not associated with OCTN1 functional promoter variants or haplotypes showing altered promoter activities in in vitro assays. However, OCTN1 functional promoter haplotypes showing decreased promoter activities were significantly associated with a penetrating behavior in CD patients (HR=2.428, p=0.009). Our results suggest that the OCTN1 functional promoter haplotypes can influence the CD phenotype, although these might not be associated with susceptibility to this disease.

Shank2 mutant mice display a hypersecretory response to cholera toxin.

Shank2 is a PDZ (PSD-95/discs large/ZO-1)-based adaptor that has been suggested to regulate membrane transporting proteins in the brain and epithelial tissues. Here, we report that Shank2 mutant (Shank2(-/-)) mice exhibit aberrant fluid and ion transport in the intestine. Molecular characterization using epithelial tissues from Shank2(+/+) and Shank2(-/-) mice revealed that a long spliceoform of Shank2 (Shank2E) is predominantly expressed in the pancreatic, renal and intestinal epithelia. In functional assays, deletion of Shank2 increased the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent short-circuit currents by 84% (P < 0.05) and 101% (P < 0.05) in the mouse colon and rectum, respectively. Disruption of the CFTR-Shank2-phosphodiesterase 4D protein complex appeared to be mostly responsible for the changes in CFTR activities. Notably, Shank2 deletion profoundly increased cholera toxin-induced fluid accumulation in the mouse intestine (∼90%, P < 0.01). Analyses with chemical inhibitors confirmed that the hyperactivation of CFTR channel function is responsible for the increased response to cholera toxin. These results suggest that Shank2 is a key molecule that participates in epithelial homeostasis, in particular to prevent overt secretory responses caused by epithelial pathogens.

Comparison of the methods for tumor response assessment in patients with hepatocellular carcinoma undergoing transarterial chemoembolization.

BACKGROUND & AIMS: Recently, new methods, including the concept of viable enhancing tumor such as EASL and mRECIST, have been proposed for substitution of the conventional WHO and RECIST criteria in hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE). Herein, we evaluated the differences of four methods and compared the association of these methods with the prognosis of HCC patients undergoing TACE. METHODS: We retrospectively reviewed 114 consecutive newly diagnosed HCC patients who underwent TACE as initial treatment. We evaluated the intermethod agreement (κ values) between the methods and compared their association with the prognosis of HCC patients. RESULTS: The κ values for EASL vs. WHO, EASL vs. RECIST, mRECIST vs. WHO, and mRECIST vs. RECIST were low, of 0.102, 0.088, 0.112, and 0.122, respectively. However, good correlations were observed for WHO vs. RECIST and EASL vs. mRECIST (κ=0.883, κ=0.759, respectively p<0.001). The median OS was 32.3 months. Hazard ratios (HR) for survival in responders compared with non-responders were 0.21 (95% CI; 0.12-0.37, p<0.001) for EASL and 0.27 (95% CI; 0.15-0.48, p<0.001) for mRECIST. The mean survival of responders was significantly longer than that of non-responders in both EASL (40.8 vs. 16.9 months, p<0.001) and mRECIST (41.1 vs. 20.7 months, p<0.001). In multivariate analysis, EASL response (HR 0.21, 95% CI 0.11-0.40, p<0.001) and mRECIST response (HR; 0.31, 95% CI, 0.17-0.59, p<0.001) were independently associated with survival. CONCLUSIONS: The response assessment by EASL and mRECIST could reliably predict the survival of HCC patients undergoing TACE and could be applicable in practice in preference to the conventional WHO and RECIST criteria.

Genome-wide association analysis reveals the associations of NPHP4, TYW1-AUTS2 and SEMA6D for Behçet's disease and HLA-B*46:01 for its intestinal involvement.

BACKGROUND: Intestinal involvement in Behçet's disease (BD) is associated with poor prognosis and is more prevalent in East Asian than in Mediterranean populations. Identifying the genetic causes of intestinal BD is important for understanding the pathogenesis and for appropriate treatment of BD patients. METHODS: We performed genome-wide association studies (GWAS) and imputation/replication genotyping of human leukocyte antigen (HLA) alleles for 1,689 Korean and Turkish patients with BD (including 379 patients with intestinal BD) and 2,327 healthy controls, followed by replication using 593 Japanese patients with BD (101 patients with intestinal BD) and 737 healthy controls. Stratified cross-phenotype analyses were performed for 1) overall BD, 2) intestinal BD, and 3) intestinal BD without association of overall BD. RESULTS: We identified three novel genome-wide significant susceptibility loci including NPHP4 (rs74566205; P=1.36 × 10-8), TYW1-AUTS2 (rs60021986; P=1.14 × 10-9), and SEMA6D (rs4143322; P=5.54 × 10-9) for overall BD, and a new association with HLA-B*46:01 for intestinal BD (P=1.67 × 10-8) but not for BD without intestinal involvement. HLA peptide binding analysis revealed that Mycobacterial peptides, have a stronger binding affinity to HLA-B*46:01 compared to the known risk allele HLA-B*51:01. CONCLUSIONS: HLA-B*46:01 is associated with the development of intestinal BD; NPHP4, TYW1-AUTS2, and SEMA6D are susceptibility loci for overall BD.

Comparison of the efficacies of lamivudine versus entecavir in patients with hepatitis B virus-related decompensated cirrhosis.

BACKGROUND: Suppression of hepatitis B virus (HBV) DNA is more potent, and occurrence of resistant strain is rare with entecavir than lamivudine, but whether these merits result in a more favourable outcome in HBV-related decompensated cirrhosis patients is unclear. AIMS: To compare virologic response, changes in liver function, clinical course and predictive factors for early mortality after treatment between patients treated with lamivudine and those with entecavir in HBV-related decompensated cirrhosis patients. METHODS: HBV-related decompensated cirrhosis patients [Child-Turcotte-Pugh (CTP) score ≥ 7] treated with either lamivudine or entecavir were enrolled. Serum HBV DNA levels, CTP score and Model for End-stage Liver Disease (MELD) score were monitored every 3 months. RESULTS: Eighty-six patients were enrolled; mean age was 54 ± 11 years, and 63 (73.3%) patients were men; 41 (47.7%) and 45 (52.3%) patients were assigned to the lamivudine group and entecavir group respectively. Although suppression of serum HBV DNA level was more potent in the entecavir group, CTP or MELD scores during the course of treatment did not differ between the two groups. Similarly, 6-month survival rates did not differ between the two groups (95.1 vs 93.2%, P = 0.684). Baseline CTP score and MELD score at 3 months of treatment were significantly associated with 6-month mortality. The 6- and 12-month mortality rates for patients with baseline CTP score ≥ 11 and MELD score ≥ 17.5 after 3 months of treatment were 42.9 and 61.9% respectively. CONCLUSIONS: Although HBV DNA suppression was more potent in the entecavir group than the lamivudine group, early mortality rates did not differ between the two groups. The baseline CTP score and MELD score 3 months after initiating antiviral treatment were significant predictors of early mortality.

The accuracy of noninvasive methods in predicting the development of hepatocellular carcinoma and hepatic decompensation in patients with chronic hepatitis B.

BACKGROUND: Liver stiffness measurement (LSM) using transient elastography (FibroScan) can accurately assess the degree of liver fibrosis and predict the development of hepatocellular carcinoma (HCC) and variceal bleeding in patients with chronic hepatitis B (CHB). AIMS: We compared the accuracy of noninvasive liver fibrosis prediction methods in predicting the development of HCC or hepatic decompensation in patients with CHB. METHODS: A total of 1126 patients with CHB who underwent LSMs and attended regular follow-ups to detect the development of HCC and hepatic decompensations (variceal bleeding, ascites, hepatic encephalopathy, spontaneous bacterial peritonitis, or hepatorenal syndrome) were enrolled. Noninvasive liver fibrosis prediction methods included, age-spleen-to-platelet ratio index, LSM, LSM-spleen diameter-to-platelet ratio index (LSPI), P2/MS, and FIB-4. RESULTS: During follow-up (median, 30.7 mo), HCC and hepatic decompensation developed in 63 and 68 patients, respectively. The accuracy of LSM and LSPI in predicting the development of HCC or hepatic decompensation was higher than that of aspartate aminotransferase-to-platelet ratio index, age-spleen-to-platelet ratio index, P2/MS, or FIB-4 (areas under the receiver operating characteristic curve=0.789 and 0.788 vs. 0.729, 0.756, 0.696, and 0.744 for HCC development; areas under the receiver operating characteristic curve=0.820 and 0.848 vs. 0.787, 0.799, 0.812, and 0.784 for hepatic decompensation). On multivariate analyses, LSM and LSPI were identified as independent predictors of the development of HCC [hazard ratio (HR), 1.040 (LSM); HR, 1.001 (LSPI)] and hepatic decompensation [HR, 1.033 (LSM); HR, 1.002 (LSPI)]. CONCLUSIONS: Our results suggest that LSM or LSPI may be useful predictors of the development of HCC and hepatic decompensation in patients with CHB.

Long-term clinical outcomes and factors predictive of relapse after 5-aminosalicylate or sulfasalazine therapy in patients with mild-to-moderate ulcerative colitis.

BACKGROUND/AIMS: Clinical outcomes and factors predictive of favorable response after 5-aminosalicylates or sulfasalazine (5-ASA/sulfasalazine) treatment alone have not been well established in the treatment of mild to moderate ulcerative colitis (UC). We evaluated the clinical course of Korean UC patients treated with 5-ASA/sulfasalazine as a maintenance therapy in terms of relapse and predictive factors of clinical relapse. METHODOLOGY: A total 256 UC patients, treated with 5-ASA/sulfasalazine at the Severance Hospital between January 2000 and December 2008, were analyzed retrospectively. We sought to investigate relapse rates and to determine independent predictors for relapse. RESULTS: Of the 256 patients, 127 patients (49.6%) had a disease relapse. The cumulative relapse rate was 21.5% after 1 year, 36.5% after 2 years, 46.9% after 3 years and 59.8% after 5 years. On multivariate analysis, left-sided or extensive colitis at diagnosis (hazard ratio=1.46; 95% CI=1.01-2.10; p=0.04) and initial hemoglobin level <10.5g/dL (hazard ratio= 0.43; 95% CI=0.22-0.81; p=0.01) were found to be independent factors for clinical relapse. CONCLUSIONS: Our study showed that both disease extent at diagnosis and anemia were major predictive factors for clinical relapse after 5-ASA/sulfasalazine therapy for Korean patients with mild to moderate UC.

What Is the Relationship between Antioxidant Efficacy, Functional Composition, and Genetic Characteristics in Comparing Soybean Resources by Year?

The aim of this study was to analyze the physiological activity of 48 soybean resources harvested in 2020 to identify the soybean resources' relationships with individual isoflavone compounds and their genetic properties. These data will subsequently be compared with the research results on soybeans harvested in 2019. Initially, with respect to the physiological activity (6 types) and substances (19 types), this study evaluated the differences between the cultivation year (two years), seed coat color (three colors), and the interaction of the year and seed coat color of soybeans through ANOVA. Among the physiological activities, there were differences in the estrogen, estrogen receptor alpha, and UCP-1 (uncoupling protein-1) activities depending on the cultivation year. Moreover, there were differences in NO (nitric oxide), revealing differences in the ABTS (2, 2'-azino-bis-3ethylbenzo-thiazoline-6-sulfonic acid) and DPPH (2, 2-diphenyl-2-picrylhydrazyl) radical scavenging activities due to the seed coat color and the interaction of the year and seed coat color. Soybeans harvested in 2020 exhibited increased ABTS, DPPH, and NO inhibitory activities and reduced estrogen, estrogen receptor alpha, and UCP-1 activities compared to those harvested in 2019. According to the ANOVA results, eight of the nineteen individual derivatives illustrated yearly differences, while three derivatives displayed differences due to the seed coat color. Secondly, according to the relationship between the efficacy, derivative substances, and genetic properties, it was determined that genistein 7-O-(2″-O-apiosyl)glucoside (F5) is the individual isoflavone derivative that affected the six types of physiological activity, on which the genome-wide association study (GWAS) showed no significant differences for genetic properties. These results were inconsistent with the 2019 data, where three types of individual compounds, including F5, were proposed as substances that correlated with efficacy and there was a high correlation with genetic properties. Therefore, this study selected B17, B23, B15, B24, and Y7 as excellent varieties that are stable and highly functional in the cultivation environment, producing only small annual differences. The results of this study will be utilized as basic data for predicting soybean varieties and their cultivation, which have high environmental stability under climate variation and properly retain the functional substances and efficacy.

Comparison of clevudine and entecavir for treatment-naive patients with chronic hepatitis B virus infection: two-year follow-up data.

BACKGROUND/AIM: Clevudine and entecavir are highly potent antiviral agents being used in treatment of chronic hepatitis B. However, no data comparing clinical efficacy and safety of these 2 drugs over a long-term period is available. The aims of this study are to compare virologic, biochemical, and serologic response rates of clevudine and entecavir, as well as treatment failure rates up to 2 years. METHODS: Data of patients who started clevudine (n = 86) or entecavir (n = 159) as a primary treatment for chronic hepatitis B at Korea University Ansan or Guro Hospital between January 2007 and June 2008 were analyzed. RESULTS: Treatment responses were compared at 3-month intervals up to 24 months. Per protocol analysis showed no difference in virologic responses between the 2 groups at all time points, except at 18 months. When analyzed on intention-to-treat basis for virologic response at 24 months, the response rates were 45.3% in the clevudine group and 72.3% in the entecavir group, which are significantly different (P < 0.001). Rates of biochemical response and HBeAg seroconversion were not significantly different between the groups at all time points. Up to 24 months, antiviral resistance developed in 18 patients (24.4%) in the clevudine group. Clevudine was discontinued owing to muscle-related problems in 10 patients (11.6%). CONCLUSIONS: Although both drugs showed potent antiviral activity, entecavir showed better virologic response at 24 months, primarily owing to treatment failures in the clevudine group that were associated with development of drug resistance and muscle-related problems.

Inter-observer variability of experts and trainees for the diagnosis of reflux esophagitis: Comparison of linked color imaging, blue laser imaging, and white light imaging.

OBJECTIVES: Diagnosis of reflux esophagitis according to the Los Angeles classification minimal change (LA-M) has a low inter-observer agreement. We aimed to investigate whether the inter-observer agreement of reflux esophagitis was better when expert endoscopists read the endoscopic images, or when the linked color imaging (LCI) or blue laser imaging (BLI)-bright mode was used. In addition, whether the inclusion of LA-M in the definition of reflux esophagitis affected the consistency of the diagnosis was investigated. METHODS: During upper endoscopy, endoscopic images of the gastroesophageal junction were taken using white light imaging (WLI), BLI-bright, and LCI modes. Four expert endoscopists and four trainees reviewed the images to diagnose reflux esophagitis according to the modified LA classification. RESULTS: The kappa values for the inter-observer variability for the diagnosis of reflux esophagitis were poor to fair among the experts (κ = â€Š0.22, 0.17, and 0.27 for WLI, BLI-bright, and LCI, respectively) and poor among the trainees (κ = â€Š0.18, 0.08, and 0.14 for WLI, BLI-bright, and LCI). The inter-observer variabilities for the diagnosis of reflux esophagitis excluding LA-M were fair to moderate (κ = â€Š0.42, 0.35, and 0.42 for WLI, BLI-bright, and LCI) among the expert endoscopists and moderate among the trainees (κ = 0.48, 0.43, and 0.51 for WLI, BLI-bright, and LCI). CONCLUSIONS: The inter-observer agreement for the diagnosis of reflux esophagitis was very low for both the expert endoscopists and the trainees, even using BLI-bright or LCI mode. However, when reflux esophagitis LA-M was excluded from the diagnosis of esophagitis, the degree of inter-observer agreement increased.