Highly TOP down-regulated genes in GML patients in comparison with controls.

<p>Highly TOP down-regulated genes in GML patients in comparison with controls.</p

Gene ontology (GO) analysis used for analysis of the altered genes.

<p>A, The bar plot showed the top ten up-regulated Enrichment Score values of the significant enrichment; B, The bar plot showed the top ten down-regulated Enrichment Score values of the significant enrichment BP.</p

Pathway analysis of DEG.

<p>A: The bar plot showed the top ten up-regulated Enrichment Score values of the significant enrichment pathway; B: The bar plot showed the top ten down-regulated Enrichment Score value of the significant enrichment pathway.</p

Validating microarray results using qRT-PCR.

<p>A, the top-4 up-regulated DEGs. B, the top-4 down-regulated DEGs. The results represented quantification of mRNA levels relative to β-actin. Normalized expression values were obtained by qRT-PCR (n = 3). C = Controls, P = GML patients.</p

Histopathological examination of gastric mucosa sections.

<p>A, Hematoxylin-eosin stained results showed appearance of the gastric mucosa in antrum region of the control group and HAPC-induced GML group (× 40 and × 400); B, The gastric mucosal damage score in control and HAPC-induced GML group. The mean scores were significantly higher in the HAPC-induced GML group when compared with a control group (P < 0.01, n = 3 per group).</p

Comparative Analysis of Gut Microbiota of Native Tibetan and Han Populations Living at Different Altitudes

<div><p>The factors driving the composition of gut microbiota are still only partly understood but appear to include environmental, cultural, and genetic factors. In order to obtain more insight into the relative importance of these factors, we analyzed the microbiome composition in subjects of Tibetan or Han descent living at different altitudes. DNA was isolated from stool samples. Using polymerase chain reaction methodology, the 16S rRNA V1–V3 regions were amplified and the sequence information was analyzed by principal coordinates analysis and Lefse analyses. Contrasting the Tibetan and Han populations both living at the 3600 m altitude, we found that the Tibetan microbiome is characterized by a relative abundance of <i>Prevotella</i> whereas the Han stool was enriched <i>in Bacteroides</i>. Comparing the microbiome of Han stool obtained from populations living at different altitudes revealed a more energy efficient flora in samples from those living at higher altitude relative to their lower-altitude counterparts. Comparison of the stool microbiome of Tibetan herders living at 4800 m to rural Tibetans living at 3600 m altitude shows that the former have a flora enriched in butyrate-producing bacteria, possibly in response to the harsher environment that these herders face. Thus, the study shows that both altitude and genetic/cultural background have a significant influence on microbiome composition, and it represents the first attempt to compare stool microbiota of Tibetan and Han populations in relation to altitude.</p></div

Rarefaction curves, with error bars showing confidence intervals, for all four groups of samples based on OTUs detected using a similarity threshold of 97% (0.97).

<p>Rarefaction curves, with error bars showing confidence intervals, for all four groups of samples based on OTUs detected using a similarity threshold of 97% (0.97).</p

Relative bacterial abundance in the gut microbiota of the Han and Tibetan populations at the phylum level.

<p>*represents p<0.05, **represents p<0.01, ***represents p<0.001.</p

Analysis of differences in the microbiota between the immigrant Han population and native Tibetans living at the same altitude (3600 m) using Lefse software (linear discriminant analysis [LDA] coupled with effect size measurements).

<p>Taxa enriched in the Tibetan population are indicated with a positive LDA score (green), and taxa enriched in the immigrant Han population have a negative score (red). Only taxa meeting an LDA significant threshold of 2 are shown. For taxa, which were defined as unclassified, no rank, uncultured or Incertae-Sedis, the name of a higher taxon level was added before its taxon abbreviation. p, phylum; c, class; o, order; f. family; g, genus; s, species.</p

Analysis of differences in the microbiota among Tibetans living at different altitudes using the Lefse software.

<p>Taxa enriched in the microbiota of Tibetans living at 4800 m are indicated with a positive LDA score (green), and taxa enriched in Tibetans living at 3600 m have a negative score (red). Only taxa meeting an LDA significant threshold of 2 are shown. For taxa, which were defined as unclassified and Incertae-Sedis, the name of a higher taxon level was added before its taxon abbreviation. g, genus.</p