Identification of Novel Prognostic Biomarkers That are Associated with Immune Microenvironment Based on GABA-Related Molecular Subtypes in Gastric Cancer.

Background: Gamma-aminobutyric acid (GABA) plays an important role in tumorigenesis and progression. Despite this, the role of Reactome GABA receptor activation (RGRA) on gastric cancer (GC) remains unclear. This study was intended to screen RGRA-related genes in GC and investigate their prognostic value. Methods: GSVA algorithm was used to assess the score of RGRA. GC patients were divided into two subtypes based on the median score of RGRA. GSEA, functional enrichment analysis, and immune infiltration analysis were performed between the two subgroups. Then, differentially expressed analysis, and weighted gene co-expression network analysis (WGCNA) were used to identify RGRA-related genes. The prognosis and expression of core genes were analyzed and validated in the TCGA database, GEO database, and clinical samples. ssGSEA and ESTIMATE algorithms were used to assess the immune cell infiltration in the low- and high-core genes subgroups. Results: High-RGRA subtype had a poor prognosis and activated immune-related pathways, as well as an activated immune microenvironment. ATP1A2 was identified to be the core gene. The expression of ATP1A2 was associated with the overall survival rate and tumor stage, and its expression was down-regulated in GC patients. Furthermore, ATP1A2 expression was positively correlated with the level of immune cells, including B cells, CD8 T cells, cytotoxic cells, DC, eosinophils, macrophages, mast cells, NK cells, and T cells. Conclusion: Two RGRA-related molecular subtypes were identified that could predict the outcome in GC patients. ATP1A2 was a core immunoregulatory gene and was associated with prognosis and immune cell infiltration in GC.

Gastrointestinal disturbance and effect of fecal microbiota transplantation in discharged COVID-19 patients.

BACKGROUND: To investigate the potential beneficial effect of fecal microbiota transplantation (FMT) on gastrointestinal symptoms, gut dysbiosis and immune status in discharged COVID-19 patients. CASE PRESENTATION: A total of 11 COVID-19 patients were recruited in April, 2020, about one month on average after they were discharged from the hospital. All subjects received FMT for 4 consecutive days by oral capsule administrations with 10 capsules for each day. In total, 5 out of 11 patients reported to be suffered from gastrointestinal symptoms, which were improved after FMT. After FMT, alterations of B cells were observed, which was characterized as decreased naive B cell (P = 0.012) and increased memory B cells (P = 0.001) and non-switched B cells (P = 0.012).The microbial community richness indicated by operational taxonomic units number, observed species and Chao1 estimator was marginally increased after FMT. Gut microbiome composition of discharged COVID-19 patients differed from that of the general population at both phylum and genera level, which was characterized with a lower proportion of Firmicutes (41.0%) and Actinobacteria (4.0%), higher proportion of Bacteroidetes (42.9%) and Proteobacteria (9.2%). FMT can partially restore the gut dysbiosis by increasing the relative abundance of Actinobacteria (15.0%) and reducing Proteobacteria (2.8%) at the phylum level. At the genera level, Bifidobacterium and Faecalibacterium had significantly increased after FMT. CONCLUSIONS: After FMT, altered peripheral lymphocyte subset, restored gut microbiota and alleviated gastrointestinal disorders were observe, suggesting that FMT may serve as a potential therapeutic and rehabilitative intervention for the COVID-19.

The evaluation of the OMOM capsule endoscopy with similar pictures elimination mode.

BACKGROUND AND OBJECTIVE: The reading of capsule endoscopy (CE) is time-consuming. Thus, several time-saving features have been added to the CE software by different CE companies. However, the similar pictures elimination mode in the OMOM capsule endoscopy software has not been evaluated yet. Our aim is to evaluate the sensitivity and specificity of the similar pictures elimination mode. METHODS: We retrospectively studied 200 consecutive capsule endoscopy procedures in Nanfang Hospital between April 2012 and July 2012, among which 52 cases were excluded for poor bowel preparation, failure to reach the colon or data missing. All images of the small-bowel were re-evaluated with four different reading modes (conventional mode and three levels of similar pictures elimination mode) by four experienced endoscopists. Then, the reading time, the number of detected lesions, κ value, sensitivity and specificity were compared between 4 methods. RESULTS: The mean reading time with levels I to III, respectively, was significantly shorter than with conventional mode (P<0.001, conventional mode 33.25min, level I 24.90min, level II 20.54min, level III 14.96min). The sensitivity between conventional mode and level I were similar (93.8% vs. 87.7%, P=0.073), while the sensitivity of levels II and III was significantly lower than conventional mode (77.8% vs. 93.8%, 70% vs. 93.8%, respectively). The specificity between all 4 modes were similar (100% for conventional mode, 98.5% for levels I to III). CONCLUSIONS: Level I reading mode was as efficient as the conventional mode and less time-consuming. Its sensitivity and specificity were similar compared with the conventional mode.