1%∼6.5%). Some of our microbiome samples were enriched in both Bacteroides and Prevotella and did not fit into the enterotypes described above. Therefore, we designated these samples as enterotype H, a hybrid between enterotypes 1 and 2. From the QIIME-generated
OTU table, all OTUs assigned to Escherichia were examined. The most abundant Escherichia OTU was identified to be OTU#20341. The DNA sequence of OTU#20341 was retrieved from a QIIME-generated FASTA file containing a representative sequence for each OTU. This sequence was used as the input for Blast search (available at: http://blast.ncbi.nlm.nih.gov), against the current 16S rRNA database (search performed on April 9, 2012). A single blood sample was collected from each patient at the time of liver biopsy (from July 26, 2010 through RG7204 ic50 June 1, 2011). A single blood sample from
each healthy and non-NASH obese subject was collected at the same period. Serum alcohol concentration was determined in subsets of obese and Selleckchem Abiraterone NASH patients in the microbiome study and a new cohort of healthy subjects. Serum samples were stored at −80 °C before ethanol concentrations were measured with an ethanol assay kit from BioVision (Milpitas, CA), following the manufacturer’s instructions. Briefly, alcohol was oxidized by alcohol oxidase, and the product was subsequently measured by a colorimetric probe (at 570 nm). A linear standard curve between alcohol concentrations and OD570 was generated and used to calculate alcohol concentrations in serum samples. One-way analysis of variance (ANOVA) and post-hoc Tukey’s honest significant difference tests for multiple comparisons were performed to evaluate differences in taxonomic abundance, alpha diversities, and serum ethanol concentrations among three groups. Fisher’s exact test was performed to examine a possible association between enterotypes and health status. ANOVA, Tukey’s, and Fisher’s tests were performed with R version 上海皓元 2.14.0. A P value less than 0.05 was considered statistically significant. Gut microbiomes of healthy, obese, and NASH children and adolescents (Table
1) were analyzed by 16S rRNA pyrosequencing. A total of 835,591 sequencing reads were obtained from a total of 63 samples. Ecological diversity within each sample was evaluated by a phylogenetic distance metric (Supporting Fig. 1A). No significant difference was observed among three groups. However, as a measurement of species richness, Chao1 metric revealed significant differences among three groups (Supporting Fig. 1B). P(ANOVA) values were <0.05 at sampling sizes 1,268, 2,526, 3,784, and 5,042 OTUs. Post-hoc Tukey’s tests indicated that differences were significant between obese and healthy controls (Tukey’s P < 0.05 at sampling sizes 1,268, 2,526, 3,784, and 5,042 OTUs). Species abundance in the NASH group was marginally lower than that of the healthy group, with Tukey’s P values of approximately 0.1. Ecological diversities within each group were accessed by UniFrac analysis.