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Background Peutz-Jeghers syndrome (PJS) is a rare genetic disorder characterized by the development of pigmented spots, gastrointestinal polyps and increased susceptibility to cancers. Currently, most studies have investigated intestinal microbiota through fecal microbiota, and there are few reports about mucosa-associated microbiota. It remains valuable to search for the key intestinal microbiota or abnormal metabolic pathways linked to PJS. Aim This study aimed to assess the structure and composition of mucosa-associated microbiota in patients with PJS and to explore the potential influence of intestinal microbiota disorders and metabolite changes on PJS. Methods The bacterial composition was analyzed in 13 PJS patients and 12 controls using 16S rRNA gene sequencing (Illumina MiSeq) for bacteria. Differential analyses of the intestinal microbiota were performed from the phylum to species level. Liquid chromatography-tandem mass spectrometry (LC-MS) was used to detect the differentially abundant metabolites of PJS patients and controls to identify different metabolites and metabolic biomarkers of small intestinal mucosa samples. Results High-throughput sequencing confirmed the special characteristics and biodiversity of the mucosa microflora in patients with PJS. They had lower bacterial biodiversity than controls. The abundance of intestinal mucosal microflora was significantly lower than that of fecal microflora. In addition, lipid metabolism, amino acid metabolism, carbohydrate metabolism, nucleotide metabolism and other pathways were significantly different from those of controls, which were associated with the development of the enteric nervous system, intestinal inflammation and development of tumors. Conclusion This is the first report on the mucosa-associated microbiota and metabolite profile of subjects with PJS, which may be meaningful to provide a structural basis for further research on intestinal microecology in PJS. Keywords: Peutz-Jeghers syndrome, Metabolomics, LC-MS, Mucosa-associated microbiota, Bacteria, Author(s): Sui Wang[sup.2], Guan-Jun Kou[sup.1], Xiao-Han Zhao[sup.1], Gang Huang[sup.1], Jue-Xin Wang[sup.1], Lin Tian[sup.1], Xiu-Li Zuo[sup.1], Yan-Qing Li[sup.1], Jia-Yong Wang[sup.3] and Yan-Bo Yu[sup.1] Introduction Peutz-Jeghers syndrome (PJS) is a rare genetic [...]

The respiratory microbiome has been less explored than the gut microbiome. Despite the speculated importance of dysbiosis of the microbiome in ventilator-associated pneumonia (VAP) and acute respiratory distress syndrome (ARDS), only few studies have been performed in invasively ventilated ICU patients. And only the results of small cohorts have been published. An overlap exists between bacterial populations observed in the lower respiratory tract and the oropharyngeal tract. The bacterial microbiota is characterized by relatively abundant bacteria difficult to cultivate by standard methods. Under mechanical ventilation, a dysbiosis occurs with a drop overtime in diversity. During VAP development, lung dysbiosis is characterized by a shift towards a dominant bacterial pathogen (mostly Proteobacteria) whereas enrichment of gut-associated bacteria mainly Enterobacteriaceae is the specific feature discriminating ARDS patients. However, the role of this dysbiosis in VAP and ARDS pathogenesis is not yet fully understood. A more in-depth analysis of the interplay between bacteria, virus and fungi and a better understanding of the host-microbiome interaction could provide a more comprehensive view of the role of the microbiome in VAP and ARDS pathogenesis. Priority should be given to validate a consensual and robust methodology for respiratory microbiome research and to conduct longitudinal studies. A deeper understanding of microbial interplay should be a valuable guide for care of ARDS and VAP preventive/therapeutic strategies. We present a review on the current knowledge and expose perspectives and potential clinical applications of respiratory microbiome research in mechanically ventilated patients., Author(s): Mélanie Fromentin [sup.1] [sup.3], Jean-Damien Ricard [sup.2] [sup.3], Damien Roux [sup.2] [sup.3] Author Affiliations: (1) grid.411784.f, 0000 0001 0274 3893, Anesthesiology and Intensive Care Department, AP-HP, Hôpital Cochin, , [...]

Background Colorectal cancer (CRC) is a multifactorial disease with genetic and environmental factors. Regional differences in risk factors are an important reason for the different incidences of CRC in different regions. Objective The goal was to clarify the intestinal microbial composition and structure of CRC patients in different regions and construct CRC risk prediction models based on regional differences. Methods A metagenomic dataset of 601 samples from 6 countries in the GMrepo and NCBI databases was collected. All whole-genome sequencing (WGS) data were annotated for species by MetaPhlAn2. We obtained the relative abundance of species composition at the species level and genus level. The MicrobiotaProcess package was used to visualize species composition and PCA. LEfSe analysis was used to analyze the differences in the datasets in each region. Spearman correlation analysis was performed for CRC differential species. Finally, the CRC risk prediction model was constructed and verified in each regional dataset. Results The composition of the intestinal bacterial community varied in different regions. Differential intestinal bacteria of CRC in different regions are inconsistent. There was a common diversity of bacteria in all six countries, such as Peptostreptococcus stomatis and Fusobacterium nucleatum at the species level. Peptostreptococcus stomatis (species level) and Peptostreptococcus (genus level) are important CRC-related bacteria that are related to other bacteria in different regions. Region has little influence on the accuracy of the CRC risk prediction model. Peptostreptococcus stomatis is an important variable in CRC risk prediction models in all regions. Conclusion Peptostreptococcus stomatis is a common high-risk pathogen of CRC worldwide, and it is an important variable in CRC risk prediction models in all regions. However, regional differences in intestinal bacteria had no significant impact on the accuracy of the CRC risk prediction model. Keywords: Colorectal cancer, Intestinal bacteria, Regional difference, Author(s): Han Shuwen[sup.1,3], Wu Yinhang[sup.3], Zhao Xingming[sup.4], Zhuang Jing[sup.3], Liu Jinxin[sup.4], Wu Wei[sup.3] and Ding Kefeng[sup.1,2] Introduction Cancer incidence and death rates are increasing worldwide. The GLOBOCAN 2020 database showed [...]

Background Emerging evidence suggests that gut microbiota plays a predominant role in Crohn's disease (CD). However, the microbiome alterations in the early stage of CD patients still remain unclear. The present study aimed to identify dysbacteriosis in patients with early CD and explore specific gut bacteria related to the progression of CD. Methods This study was nested within a longitudinal prospective Chinese CD cohort, and it included 18 early CD patients, 22 advanced CD patients and 30 healthy controls. The microbiota communities were investigated using high-throughput Illumina HiSeq sequencing targeting the V3-V4 region of 16S ribosomal DNA (rDNA) gene. The relationship between the gut microbiota and clinical characteristics of CD was analyzed. Results Differential microbiota compositions were observed in CD samples (including early and advanced CD samples) and healthy controls samples. Notably, Lachnospiracea_incertae_sedis and Parabacteroides were enriched in the early CD patients, Escherichia/Shigella, Enterococcus and Proteus were enriched in the advanced CD patients, and Roseburia, Gemmiger, Coprococcus, Ruminococcus 2, Butyricicoccus, Dorea, Fusicatenibacter, Anaerostipes, Clostridium IV were enriched in the healthy controls [LDA score (log10) > 2]. Furthermore, Kruskal-Wallis Rank sum test results showed that Blautia, Clostridium IV, Coprococcus, Dorea, Fusicatenibacter continued to significantly decrease in early and advanced CD patients, and Escherichia/Shigella and Proteus continued to significantly increase compared with healthy controls (P < 0.05). The PICRUSt analysis identified 16 remarkably different metabolic pathways [LDA score (log10) > 2]. Some genera were significantly correlated with various clinical parameters, such as fecal calprotectin, erythrocyte sedimentation rate, C-reactive protein, gland reduce, goblet cells decreased, clinical symptoms (P < 0.05). Conclusions Dysbacteriosis occurs in the early stage of CD and is associated with the progression of CD. This data provides a foundation that furthers the understanding of the role of gut microbiota in CD's pathogenesis. Keywords: Crohn's disease, Early diagnosis, Gut microbiota, 16S rDNA, Dysbacteriosis, Author(s): Xianzong Ma[sup.1,2], Xiaojuan Lu[sup.2], Wenyu Zhang[sup.3], Lang Yang[sup.2,4], Dezhi Wang[sup.1,2], Junfeng Xu[sup.4], Yan Jia[sup.2], Xin Wang[sup.2], Hui Xie[sup.2], Shu Li[sup.2], Mingjie Zhang[sup.2], Yuqi He[sup.2], Peng Jin[sup.2,4] and Jianqiu Sheng[sup.1,2,4] [...]

Resident microbiota activates regulatory cells that modulate intestinal inflammation and promote and maintain intestinal homeostasis. IL-10 is a key mediator of immune regulatory function. Our studies describe the functional importance and mechanisms by which gut microbiota and specific microbial components influence the development of intestinal IL10-producing B cells. Using fecal transplant into germ-free (GF) [Il10.sup.+/EGFP] reporter and [Il10.sup.-/-] mice, we demonstrated that microbiota from specific pathogen-free mice primarily stimulated IL-10-producing colon-specific B cells and T regulatory 1 cells in ex-GF mice. IL-10 in turn downregulated microbiota-activated mucosal inflammatory cytokines. TLR2 and -9 ligands and enteric bacterial lysates preferentially induced IL-10 production and the regulatory capacity of intestinal B cells. Analysis of [IL10.sup.+/EGFP] mice crossed with additional gene-deficient strains and B cell cotransfer studies demonstrated that microbiota-induced IL-10-producing intestinal B cells ameliorated chronic T cell-mediated colitis in a TLR2-, MyD88-, and PI3K-dependent fashion. In vitro studies implicated downstream signaling of PI3Kp110[delta] and AKT. These studies demonstrated that resident enteric bacteria activated intestinal IL-10-producing B cells through TLR2, MyD88, and PI3K pathways. These B cells reduced colonic T cell activation and maintained mucosal homeostasis in response to intestinal microbiota., Introduction Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are T cell-mediated, chronic disorders whose development is influenced in part by dysregulated, aggressive intestinal mucosal immune reactions to [...]

Purpose To compare bacteria recovered by standard cultures and metataxonomics, particularly with regard to ventilator-associated pneumonia (VAP) pathogens, and to determine if the presence of particular bacteria or microbiota in tracheal and oropharyngeal secretions during the course of intubation was associated with the development of VAP. Methods In this case-control study, oropharyngeal secretions and endotracheal aspirate were collected daily in mechanically ventilated patients. Culture and metataxonomics (16S rRNA gene-based taxonomic profiling of bacterial communities) were performed on serial upper respiratory samples from patients with late-onset definite VAP and their respective controls. Results Metataxonomic analyses showed that a low relative abundance of Bacilli at the time of intubation in the oropharyngeal secretions was strongly associated with the subsequent development of VAP. On the day of VAP, the quantity of human and bacterial DNA in both tracheal and oropharyngeal secretions was significantly higher in patients with VAP than in matched controls with similar ventilation times. Molecular techniques identified the pathogen(s) of VAP found by culture, but also many more bacteria, classically difficult to culture, such as Mycoplasma spp. and anaerobes. Conclusions Molecular analyses of respiratory specimens identified markers associated with the development of VAP, as well as important differences in the taxa abundance between VAP and controls. Further prospective trials are needed to test the predictive value of these markers, as well as the relevance of uncultured bacteria in the pathogenesis of VAP., Author(s): Stéphane Emonet [sup.1] [sup.2], Vladimir Lazarevic [sup.3], Corinne Leemann Refondini [sup.4], Nadia Gaïa [sup.3], Stefano Leo [sup.3], Myriam Girard [sup.3], Valérie Nocquet Boyer [sup.4], Hannah Wozniak [sup.4], Lena Després [...]

Background Lentibacillus species are gram variable aerobic bacteria that live primarily in halophilic environments. Previous reports have shown that bacteria belonging to this species are primarily isolated from salty environments or food. We isolated a bacterial strain CBA3610, identified as a novel species of the genus Lentibacillus, from a human fecal sample. In this report, the whole genome sequence of Lentibacillus sp. CBA3610 is presented, and genomic analyses are performed. Results Complete genome sequence of strain CBA3610 was obtained through PacBio RSII and Illumina HiSeq platforms. The size of genome is 4,035,571 bp and genes estimated to be 4714 coding DNA sequences and 64 tRNA and 17 rRNA were identified. The phylogenetic analysis confirmed that it belongs to the genus Lentibacillus. In addition, there were genes related to antibiotic resistance and virulence, and genes predicted as CRISPR and prophage were also identified. Genes related to osmotic stress were found according to the characteristics of halophilic bacterium. Genomic differences from other Lentibacillus species were also confirmed through comparative genomic analysis. Conclusions Strain CBA3610 is predicted to be a novel candidate species of Lentibacillus through phylogenetic analysis and comparative genomic analysis with other species in the same genus. This strain has antibiotic resistance gene and pathogenic genes. In future, the information derived from the results of several genomic analyses of this strain is thought to be helpful in identifying the relationship between halophilic bacteria and human gut microbiota. Keywords: Lentibacillus sp. CBA3610, Complete genome sequence, Gut microbiota, Halophile, Author(s): Seung Woo Ahn[sup.1], Se Hee Lee[sup.1], Hong-Seok Son[sup.2], Seong Woon Roh[sup.1] and Yoon-E Choi[sup.3] Background Lentibacillus is a gram-variable, aerobic or facultatively anaerobic, and halophilic bacterial genus of the [...]

Background Inflammatory bowel disease caused by microbial dysbiosis is an important factor contributing to colorectal cancer (CRC) initiation. The 'driver-passenger' model in human gut microbial dysbiosis suggests that 'driver' bacteria may colonize with low relative abundance on tumor site but persistently induce chronic change in normal intestinal epithelium and initiate CRC. They are gradually replaced by 'passenger' bacteria later on, due to their low adaptability to the on-tumor site niche. Results To reveal site-specific bacterial taxon markers in CRC patients, we analyzed the gut mucosal microbiome of 75 paired samples of on-tumor and tumor-adjacent sites, 75 off-tumor sites, and 26 healthy controls. Linear discriminant analysis of relative abundance profiles revealed unique bacterial taxon distribution correlated with specific tumor sites, with Eubacterium having the distribution characteristic of potential driver bacteria. We further show that Eubacterium rectale endotoxin activates the transcription factor NF-κÎ, which regulates multiple aspects of innate and adaptive immune responses in normal colon epithelial cells. Unlike the 'passenger' bacterium Fusobacterium nucleatum, E. rectale promotes dextran sodium sulfate-induced colitis in Balb/c mice. Conclusions Our findings reveal that E. rectale functions as a 'driver' bacterium and contributes to cancer initiation via promoting inflammation. Keywords: Eubacterium rectale, Colorectal cancer, 'driver-passenger' model, Colitis, Microbiota, Author(s): Yijia Wang[sup.1], Xuehua Wan[sup.2], Xiaojing Wu[sup.1], Chunze Zhang[sup.1], Jun Liu[sup.1] and Shaobin Hou[sup.3] Background The adenoma-carcinoma sequence indicates that the accumulation of genetic and epigenetic alterations induces malignant epithelial [...]

Purpose Selective digestive microbial decontamination (SDD) is hypothesized to benefit patients in intensive care (ICU) by suppressing Gram-negative potential pathogens from the colon without affecting the anaerobic intestinal microbiota. The purpose of this study was to provide more insight to the effects of digestive tract and oropharyngeal decontamination on the intestinal microbiota by means of a prospective clinical trial in which faecal samples were collected from ICU patients for intestinal microbiota analysis. Methods The faecal samples were collected from ICU patients enrolled in a multicentre trial to study the outcome of SDD and selective oral decontamination (SOD) in comparison with standard care (SC). Fluorescent in situ hybridization (FISH) was used to analyze the faecal microbiota. The numbers of bacteria from different bacterial groups were compared between the three regimens. Results The total counts of bacteria per gram faeces did not differ between regimens. The F. prausnitzii group of bacteria, representing an important group among intestinal microbiota, was significantly reduced in the SDD regimen compared to the SC and SOD. The Enterobacteriaceae were significantly suppressed during SDD compared to both SOD and SC; enterococci increased in SDD compared to both other regimens. Conclusions The composition of the intestinal microbiota is importantly affected by SDD. The F. prausnitzii group was significantly suppressed during SDD. This group of microbiota is a predominant producer of butyrate, the main energy source for colonocytes. Reduction of this microbiota is an important trade-off while reducing gram-negative bacteria by SDD., Author(s): Robin F. Benus [sup.1] [sup.2] [sup.3], Hermie J. Harmsen [sup.1], Gjalt W. Welling [sup.1], Rob Spanjersberg [sup.2], Jan G. Zijlstra [sup.2], John E. Degener [sup.1], Tjip S. van der [...]

Byline: Hilal Urusan and S. Canan Bolukbasi ABSTRACT The study was conducted to determine the effect of turmeric powder at different levels (0, 2, 4, 6, 8, 10 g/ kg), [...]