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Atrial fibrillation (AF) reduces the quality of life by triggering stroke and heart failure. The association between AF onset and gut metabolites suggests a causal relationship between AF and gut microbiota dysbiosis; however, the relationship remains poorly understood. We prospectively enrolled 34 hospitalized patients with AF and 66 age-, sex-, and comorbidity-matched control subjects without a history of AF. Gut microbial compositions were evaluated by amplicon sequencing targeting the 16S ribosomal RNA gene. We assessed differences in dietary habits by using a brief-type self-administered diet history questionnaire (BDHQ). Gut microbial richness was lower in AF patients, although the diversity of gut microbiota did not differ between the two groups. At the genus level,Enterobacterwas depleted, whileParabacteroides,Lachnoclostridium,Streptococcus,andAlistipeswere enriched in AF patients compared to control subjects. The BDHQ revealed that the intake of n-3 polyunsaturated fatty acids and eicosadienoic acid was higher in AF patients. Our results suggested that AF patients had altered gut microbial composition in connection with dietary habits.

The commensal microbiota is involved in a variety of diseases. Our group has noticed that patients with Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) often present with persistent inflammation of the ocular surface, even in the chronic stage, and that this inflammation is exacerbated by colonization of the mucosa by certain bacteria. However, the changes in the composition of the ocular microbiome in SJS/TEN patients with severe ocular complications (SOCs) remain to be fully investigated. Here, we conducted a cross-sectional study of 46 Japanese subjects comprising 9 healthy control subjects and 37 SJS/TEN patients with SOC. The 16S rRNA-based genetic analyses revealed that the diversity of the ocular microbiome was reduced in SJS/TEN patients with SOC compared with that in healthy control subjects. Principal coordinate analysis based on Bray–Curtis distance at the genus level revealed that the relative composition of the ocular microbiome was different in healthy control subjects and SJS/TEN patients with SOC, and that the SJS/TEN patients with SOC could be divided into four groups based on whether their microbiome was characterized by enrichment of species in genus Corynebacterium 1, Neisseriaceae uncultured, or Staphylococcus or by simultaneous enrichment in species in genera Propionibacterium, Streptococcus, Fusobacterium, Lawsonella, and Serratia. Collectively, our findings indicate that enrichment of certain bacteria at the ocular surface could be associated with ocular surface inflammation in SJS/TEN patients with SOC.

Background and Objectives: The gut microbiota is associated with human health and dietary nutrition. Various studies have been reported in this regard, but it is difficult to clearly analyze human gut microbiota as individual differences are significant. The causes of these individual differences in intestinal microflora are genetic and/or environmental. In this study, we focused on differences between identical twins in Japan to clarify the effects of nutrients consumed on the entire gut microbiome, while excluding genetic differences. Materials and Methods: We selected healthy Japanese monozygotic twins for the study and confirmed their zygosity by matching 15 short tandem repeat loci. Their fecal samples were subjected to 16S rRNA sequencing and bioinformatics analyses to identify and compare the fluctuations in intestinal bacteria. Results: We identified 12 genera sensitive to environmental factors, and found that Lactobacillus was relatively unaffected by environmental factors. Moreover, we identified protein, fat, and some nutrient intake that can affect 12 genera, which have been identified to be more sensitive to environmental factors. Among the 12 genera, Bacteroides had a positive correlation with retinol equivalent intake (rs = 0.38), Lachnospira had a significantly negative correlation with protein, sodium, iron, vitamin D, vitamin B6, and vitamin B12 intake (rs = −0.38, −0.41, −0.39, −0.63, −0.42, −0.49, respectively), Lachnospiraceae ND3007 group had a positive correlation with fat intake (rs = 0.39), and Lachnospiraceae UCG-008 group had a negative correlation with the saturated fatty acid intake (rs = −0.45). Conclusions: Our study is the first to focus on the relationship between human gut microbiota and nutrient intake using samples from Japanese twins to exclude the effects of genetic factors. These findings will broaden our understanding of the more intuitive relationship between nutrient intake and the gut microbiota and can be a useful basis for finding useful biomarkers that contribute to human health.

Background: The gut microbiome plays an important role in the immune system and has attracted attention as a biomarker of various diseases, including cancer. As such, we examined the relationship between the gut microbiome and lung cancer progression. In addition, we assessed the correlation between the gut microbiome and epidermal growth factor receptor (EGFR) mutation status.Methods: Female never-smokers diagnosed with lung adenocarcinoma were consecutively and prospectively enrolled between May 2018 and August 2019. Fecal samples were collected within 1 month before or after diagnosis and before administration of any lung cancer treatment. Principal coordinate analyses were retrospectively performed using Bray-Curtis distance matrices to investigate the effects of clinical variables (age, body mass index, Tumor-Node-Metastasis stage, T category, N category, M category, primary tumor size, performance status, and EGFR mutation status) on the gut microbial community. A correlation analysis was also performed to determine the strength of association between the dominant taxonomy (comprising ≥1% of the relative abundance of bacterial DNA sequences) and clinical variables.Results: A total of 37 patients were enrolled. T category and primary tumor size were significantly correlated with the gut microbial community (p=0.018 and 0.041, respectively). At the genus level, a significant positive correlation was observed between the relative abundance of Faecalibacterium and both T category (correlation coefficient, R=0.51, p=0.0013) and primary tumor size (R=0.37, p=0.024), whereas a significant negative correlation was observed between the relative abundances of Fusicatenibacter and Bacteroides and T category (R=−0.35, p=0.034 and R=−0.32, p=0.05, respectively) and primary tumor size (R=−0.36, p=0.029 and R=−0.41, p=0.012, respectively). EGFR mutation status had no statistically significant effect on the gut microbial community (p=0.11). However, the relative abundances of Bifidobacterium and Faecalibacterium were significantly higher in EGFR mutation–negative patients than EGFR mutation–positive patients (p=0.012 and 0.041), whereas the relative abundance of Blautia was significantly lower in EGFR mutation–negative patients (p=0.036).Conclusions: This is the first study identifying the gut microbiome as a promising biomarker of lung cancer progression. Further elucidation of the role of the gut microbiome in lung cancer progression could facilitate development of new treatments for lung cancer.

The pathogenesis of pulmonary arterial hypertension is closely associated with dysregulated inflammation. Recently, abnormal alterations in gut microbiome composition and function were reported in a pulmonary arterial hypertension experimental animal model. However, it remains unclear whether these alterations are a result or the cause of pulmonary arterial hypertension. The purpose of this study was to investigate whether alterations in the gut microbiome affected the hemodynamics in SU5416/hypoxia rats. We used the SU5416/hypoxia rat model in our study. SU5416/hypoxia rats were treated with a single SU5416 injection (30 mg/kg) and a three-week hypoxia exposure (10% O 2 ). Three SU5416/hypoxia rats were treated with a combination of four antibiotics (SU5416/hypoxia + ABx group) for four weeks. Another group was exposed to hypoxia (10% O 2 ) without the SU5416 treatment, and control rats received no treatment. Fecal samples were collected from each animal, and the gut microbiota composition was analyzed by 16S rRNA sequencing. The antibiotic treatment significantly suppressed the vascular remodeling, right ventricular hypertrophy, and increase in the right ventricular systolic pressure in SU5416/hypoxia rats. 16S rRNA sequencing analysis revealed gut microbiota modification in SU5416/hypoxia + ABx group. The Firmicutes-to-Bacteroidetes ratio in SU5416/hypoxia rats was significantly higher than that in control and hypoxia rats. Compared with the control microbiota, 14 bacterial genera, including Bacteroides and Akkermansia , increased, whereas seven bacteria, including Rothia and Prevotellaceae , decreased in abundance in SU5416/hypoxia rats. Antibiotic-induced modification of the gut microbiota suppresses the development of pulmonary arterial hypertension. Dysbiosis may play a causal role in the development and progression of pulmonary arterial hypertension.

Background: Pulmonary arterial hypertension (PAH) is an intractable disease, the development of which may be related to the inflammatory system. Recently, abnormal characteristics of gut microbiota in a PAH rat model (Su/Hx) were reported, but it has not yet been clarified whether abnormality of microbiota is a cause or result of PAH, which is therefore the purpose of this study. Methods: Su/Hx was induced in Sprague Dawley rats by subcutaneous injection of the VEGF antagonist SU 5416 (30 mg/kg) and exposure to hypoxia (10% O2). Some Su/Hx rats were treated with antibiotics (ampicillin, vancomycin, neomycin, and metronidazole) (Su/Hx+ABx group). Control rats were kept in normoxia. Alteration of pulmonary vessels within the lungs was analyzed. Preliminarily, we also collected fecal samples of patients with chronic thromboembolic pulmonary hypertension (CTEPH). Gut microbiomes were analyzed by 16S rRNA gene sequencing. Results: Right ventricular systolic pressure (RVSP) in control, Su/Hx, and Su/Hx+ABx groups was 27.8±5.1, 52.2±13.7, and 29.1±4.6 mmHg, respectively (control vs. Su/Hx: p=0.005; Su/Hx vs. Su/Hx+ABx: p=0.02; control vs. Su/Hx+ABx: p=1.0). The percentage of obstructed pulmonary arteries in the Su/Hx+ABx group was significantly lower than in the Su/Hx group (Su/Hx: 23.6±5.3; Su/Hx+ABx: 9.5±6.3; p=0.002). 16S rRNA gene sequence analysis revealed that the percentages of several bacterial species were significantly correlated with RVSP in the rats and the percentage of a bacterial species X was positively correlated with pulmonary vascular resistance (r=0.76, p=0.049) in CTEPH patients. In conclusion, altering gut microbiota could affect the development of pulmonary hypertension.

It is important to determine the cause of increasing oral cancer occurrence and mortality rates in Japan, because the mortality rate has recently decreased in other developed countries. The impact of microbiota in carcinogenesis, especially in the digestive tract has been reported. This study aimed to clarify the relationship between oral cancer and oral microbiota in Japanese patients.DNA was extracted from salivary samples of 60 oral cancer patients and 80 non-cancer individuals as controls. We performed metagenomic analysis using 16S rRNA amplicon sequencing. Statistical analysis in this study was performed using R (version 3.5.0).Oral cancer patients showed higher α-diversity compared to the control group, and the β-diversity between the two groups differed significantly. Further, there was a significant difference in the abundance ratio of bacterial genera between the two groups. Peptostreptococcus, Fusobacterium, Alloprevotella, and Capnocytophaga were more abundant in the cancer group compared to the control, whereas Rothia and Haemophilus were less abundant (p 0.01). A negative correlation in the microbiota composition was confirmed between the operational taxonomic units (OTU) of genus Rothia and T-stage progression using the TNM classification method. We performed logistic regression analysis to investigate the impact factor for the oral cancer group, and the result showed that Chao 1 index and sex are statistically significant variables.In this study, we observed an increased bacterial diversity in oral cancer patients and found distribution changes for some bacteria.

The Korea Astronomy and Space Science Institute (KASI) has established International GNSS Service (IGS) Global Data Center(GDC). The KASI GDC is the 4th official IGS GDC and the 1st GDC in the Asia-Oceania region. The KASI GDC archives IGS GNSS data and provides the IGS GPS tracking data and the IGS products. The amount of handling data of GDC is has been increased rapidly. The high performance and the reliability of the storage system to handle a very large amount of the GDC data have been very important. We applied RAID and LVM to construct a storage system for the GDC which needs a very reliable large capacity storage system. We estimated the performance of the vast storage system