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Background: Metagenome sampling bias for geographical location and lifestyle is partially responsible for the incomplete catalog of reference genomes of gut microbial species. Thus, genome assembly from currently under-represented populations may effectively expand the reference gut microbiome and improve taxonomic and functional profiling. Methods: We assembled genomes using public whole-metagenomic shotgun sequencing (WMS) data for 110 and 645 fecal samples from India and Japan, respectively. In addition, we assembled genomes from newly generated WMS data for 90 fecal samples collected from Korea. Expecting genome assembly for low-abundance species may require a much deeper sequencing than that usually employed, so we performed ultra-deep WMS (> 30 Gbp or > 100 million read pairs) for the fecal samples from Korea. We consequently assembled 29,082 prokaryotic genomes from 845 fecal metagenomes for the three under-represented Asian countries and combined them with the Unified Human Gastrointestinal Genome (UHGG) to generate an expanded catalog, the Human Reference Gut Microbiome (HRGM). Results: HRGM contains 232,098 non-redundant genomes for 5414 representative prokaryotic species including 780 that are novel, > 103 million unique proteins, and > 274 million single-nucleotide variants. This is an over 10% increase from the UHGG. The new 780 species were enriched for the Bacteroidaceae family, including species associated with high-fiber and seaweed-rich diets. Single-nucleotide variant density was positively associated with the speciation rate of gut commensals. We found that ultra-deep sequencing facilitated the assembly of genomes for low-abundance taxa, and deep sequencing (e.g., > 20 million read pairs) may be needed for the profiling of low-abundance taxa. Importantly, the HRGM significantly improved the taxonomic and functional classification of sequencing reads from fecal samples. Finally, analysis of human self-antigen homologs on the HRGM species genomes suggested that bacterial taxa with high cross-reactivity potential may contribute more to the pathogenesis of gut microbiome-associated diseases than those with low cross-reactivity potential by promoting inflammatory condition. Conclusions: By including gut metagenomes from previously under-represented Asian countries, Korea, India, and Japan, we developed a substantially expanded microbiome catalog, HRGM. Information of the microbial genomes and coding genes is publicly available (www.mbiomenet.org/HRGM/). HRGM will facilitate the identification and functional analysis of disease-associated gut microbiota. [ABSTRACT FROM AUTHOR]

This article explains that this issue of the "International Journal of Public Administration" is devoted to papers which discuss and compare Asian public administrations from the past to the current state-of-the-art thinking and practice. Ten of the papers discuss theory and practice of public administration in Southeast Asia, Asian values and administrative reform, Lacanian discourse analysis of the South Korean system, China's administrative reform and New Public Management, New Public Management in Japan, bureaucratic accountability in Southeast Asia, and other topics.

Background: The prognostic implication of mildly reduced ejection fraction (mrEF) after acute myocardial infarction has not been clearly demonstrated. We investigated the long-term risk of cardiovascular death and its predictors in patients with mrEF following acute myocardial infarction., Methods and Results: A total of 18 668 patients who presented with acute myocardial infarction were included in 2 prospective, multicenter registries. The incidence of adverse cardiovascular events according to the left ventricular ejection fraction (EF) strata at index admission were evaluated. A score system consisting of clinical variables were developed to predict long-term cardiovascular death in the mrEF group. There were 2548 patients with reduced EF (EF ≤40%), 4266 patients with mrEF (EF 41%-49%), and 11 854 patients with preserved EF (EF ≥50%). During a median follow-up period of 37.9 months, the cardiovascular death rate was 22.3% in the reduced EF group, 10.3% in the mrEF group, and 7.3% in the preserved EF group ( P <0.001). In the mrEF group, age>65 years, hypertension, stroke, severe renal insufficiency, and Killip class ≥3 were independent predictors for cardiovascular death. Presence of >2 predictors best discriminated the high-risk patients for cardiovascular death with an area under the curve of 0.746. Incidence of cardiovascular death in the high-risk mrEF group was comparable with the rEF group, while it was lower in the low-risk mrEF group than in the pEF group., Conclusions: Patients with mrEF after acute myocardial infarction had a modest risk of cardiovascular death. Clinical predictors could help discriminate a high-risk subpopulation with cardiovascular death risks comparable with those in the reduced EF group.

Gastric cancer is classified into intestinal and diffuse types, the latter including a highly malignant form, linitis plastica. A two-stage genome-wide association study (stage 1: 85,576 SNPs on 188 cases and 752 references; stage 2: 2,753 SNPs on 749 cases and 750 controls) in Japan identified a significant association between an intronic SNP (rs2976392) in PSCA (prostate stem cell antigen) and diffuse-type gastric cancer (allele-specific odds ratio (OR) = 1.62, 95% CI = 1.38-1.89, P = 1.11 x 10(-9)). The association was far less significant in intestinal-type gastric cancer. We found that PSCA is expressed in differentiating gastric epithelial cells, has a cell-proliferation inhibition activity in vitro and is frequently silenced in gastric cancer. Substitution of the C allele with the risk allele T at a SNP in the first exon (rs2294008, which has r(2) = 0.995, D' = 0.999 with rs2976392) reduces transcriptional activity of an upstream fragment of the gene. The same risk allele was also significantly associated with diffuse-type gastric cancer in 457 cases and 390 controls in Korea (allele-specific OR = 1.90, 95% CI = 1.56-2.33, P = 8.01 x 10(-11)). The polymorphism of the PSCA gene, which is possibly involved in regulating gastric epithelial-cell proliferation, influences susceptibility to diffuse-type gastric cancer.

Mutations of p53, K-ras, c-kit, and beta-catenin gene were examined in 100 cases of sinonasal NK/T-cell lymphoma (NKTCL) from Korea and Japan. Age of patients ranged from 12 to 72 (median 41.0) in Korea and 27 to 82 (median 61.0) years in Japan. Gene mutations were analyzed on paraffin-embedded specimens by PCR-SSCP followed by direct sequencing. p53 is a well-known tumor suppressor gene. c-kit gene encodes a receptor tyrosine kinase, which plays a crucial role in proliferation and differentiation of hematopoietic stem cells. Mutations of K-ras and beta-catenin are frequently observed in cancers. Thirteen of 42 (31.0%) cases from Korea and 36 of 58 (62.1%) from Japan had p53 mutations, showing significant differences in the incidence of p53 mutation between two countries. Of the Japanese cases 18 (31.0%) had mutations in exon 4, while only 3 cases (7.1%) were found in Korea cases (p<0.01 by chi2 test). K-ras, c-kit and beta-catenin mutations were also found in higher incidence in Japanese cases. In conclusion, different frequency of p53 mutations with different pattern of exon involvement and difference in age of disease onset is evident between sinonasal NKTCL in Korea and Japan.