No abstract

Long-term antibiotic use can have consequences on systemic diseases, such as obesity, allergy, and depression, implicating the causal role of gut microbiome imbalance. However, the evaluation of the effect of antibiotics in early infancy on alterations to the gut microbiome remains poorly understood. This study aimed to evaluate the gut microbiome state in infancy following systemic antibiotic treatment. Twenty infants under 3 months of age who had received antibiotics for at least 3 days were enrolled, and their fecal samples were collected 4 weeks after antibiotic administration finished. Thirty-four age-matched healthy controls without prior exposure to antibiotics were also assessed. The relative bacterial abundance in feces was obtained via sequencing of 16 S rRNA genes, and alpha and beta diversities were evaluated. At the genus level, the relative abundance of Escherichia/Shigella and Bifidobacterium increased (p = 0.03 and p = 0.017, respectively) but that of Bacteroides decreased (p = 0.02) in the antibiotic treatment group. The microbiome of the antibiotic treatment group exhibited an alpha diversity lower than that of the control group. Thus, systemic antibiotic administration in early infancy affects the gut microbiome composition even after a month has passed; long-term studies are needed to further evaluate this.

We aimed to investigate associations of dietary diversity (DD) with gut microbial diversity and the development of hen's egg allergy (HEA) in infants. We enrolled 68 infants in a high-risk group and 32 infants in a control group based on a family history of allergic diseases. All infants were followed from birth until 12 months of age. We collected infant feeding data, and DD was defined using 3 measures: the World Health Organization definition of minimum DD, food group diversity, and food allergen diversity. Gut microbiome profiles and expression of cytokines were evaluated by bacterial 16S rRNA sequencing and real-time reverse transcriptase-polymerase chain reaction. High DD scores at 3 and 4 months were associated with a lower risk of developing HEA in the high-risk group, but not in the control group. In the high-risk group, high DD scores at 3, 4, and 5 months of age were associated with an increase in Chao1 index at 6 months. We found that the gene expression of IL-4, IL-5, IL-6, and IL-8 were higher among infants who had lower DD scores compared to those who had higher DD scores in high-risk infants. Additionally, high-risk infants with a higher FAD score at 5 months of age showed a reduced gene expression of IL-13. Increasing DD within 6 months of life may increase gut microbial diversity, and thus reduce the development of HEA in infants with a family history of allergic diseases.

Background: Staphylococcus (S) aureus colonization is known to cause skin barrier disruption in atopic dermatitis (AD) patients. However, it has not been studied how S. aureus induces aberrant epidermal lipid composition and skin barrier dysfunction.Methods: Skin tape strips (STS) and swabs were obtained from 24 children with AD (6.0 ± 4.4 years) and 16 healthy children (7.0 ± 4.5 years). Lipidomic analysis of STS samples was performed by mass spectrometry. Skin levels of methicillin-sensitive and methicillin-resistant S. aureus (MSSA and MRSA) were evaluated. The effects of MSSA and MRSA were evaluated in primary human keratinocytes (HEKs) and organotypic skin cultures. Results: AD and organotypic skin colonized with MRSA significantly increased the proportion of lipid species with nonhydroxy fatty acid sphingosine ceramide with palmitic | 1293 KIM et al.

Background Common bile duct (CBD) stone is one of the most prevalent gastroenterological diseases, but the role played by biliary microbiota in the pathogenesis of CBD stones remains obscure. The aim of this study was to investigate the characteristics of the biliary tract core microbiome and its potential association with the formation of pigment stones. Methods Twenty-eight patients with biliary obstruction of various causes were enrolled. Thirteen had new-onset pigment CBD stone. Of the remaining 15, four had benign biliary stricture, four had gallbladder cancer, three had pancreatic cancer, 3 had distal CBD cancer, and one had hepatocellular carcinoma. Endoscopic retrograde cholangiopancreatography was used to collect bile samples for DNA extraction, 16S ribosomal RNA gene sequencing, and bile microbiota composition analysis. Results Proteobacteria (61.7%), Firmicutes (25.1%), Bacteroidetes (5%), Fusobacteria (4.6%), and Actinobacteria (2.6%) were the most dominant phyla in the bile of the 28 study subjects. A comparison between new-onset choledocholithiasis and other causes of biliary obstruction (controls) showed Enterococcus was found to be significantly abundant in the CBD stone group at the genus level (linear discriminant analysis score = 4.38; P = 0.03). However, no other significant compositional difference was observed. Conclusion This study demonstrates an abundance of microbiota in bile juice and presents a biliary microbiome composition similar to that of duodenum. The study also shows Enterococcus was significantly abundant in the bile juice of patients with a brown pigment stone than in controls, which suggests Enterococcus may play an important role in the development of pigment stones.