Figure 2.

The OPLS-DA model and volcano map of MDR-TB/DS-TB group in T3 column. The OPLS-DA score scatter plots of ion mode: (a) positive, (c) negative. The permutation test results of ion mode: (b) positive, (d) negative. The differential metabolite volcano maps of ion mode: (e) positive, (f) negative. The upward trend in metabolites was indicated by red scatters, the downward trend in metabolites was indicated by blue scatters, and the non-significant trend in metabolites was indicated by black scatters. (A color version of this figure is available in the online journal.)