Fig. 3: Muscle staining and ultrastructural analyses.
From: DNA2 mutation causing multisystemic disorder with impaired mitochondrial DNA maintenance
A HE staining, small angular and round atrophic muscle fibers were scattered. B Acid reaction series of ATPase confirmed vacuole formation in muscle fibers, and atrophy of type II muscle fibers could be seen. C NADH-TR staining revealed that the distribution of oxidase activity in a few muscle fibers was uneven, and atrophic muscle fibers exhibited intense staining. D COX-SDH staining revealed the enzyme activities of many muscle fibers decreased, with granular deep staining in individual muscle fibers. No RBF, SSV, or Cox negative muscle fibers were found. E The size and morphology of mitochondria were uneven, and the cristae structure was not clear. The number of mitochondria increased, with an enlarged volume and disrupted cristae
