Fig. 2

Brainstem and seventh cervical cord at the same magnification respectively. All patients showed marked nerve fiber loss of the brainstem tegmentum including the brainstem reticular formation and both lateral and anterior funiculus in addition to pyramidal tract, and showed marked atrophy of the anterior horn of the spinal cord. The medulla oblongata and spinal cords showed severe atrophy and the fourth ventricle was markedly dilatated with severe degeneration of the hypoglossal nucleus in all patients. The midbrain and pons showed severe atrophy in patients 2 with phosphorylated TAR DNA-binding protein 43 (pTDP-43)-immunoreactive (ir) neuronal cytoplasmic inclusions (NCI) (a) and patient 7 with fused in sarcoma (FUS)-ir NCI (c) in whom brain weight was less than 1000 g, mild to moderate atrophy in patient 5 with pTDP-43-ir NCI (b), patient 8 with FUS-ir NCI (d), and patient 10 with copper/zinc superoxide dismutase (SOD1)-ir NCI (e) in whom brain weight was more than 1000 g. The superior cerebellar peduncle in patients 5 (b) and 8 (d) were degenerated mildly. Loss of transverse fibers of the pons and middle cerebellar peduncle were observed only in patient 8 (d). The posterior column of the spinal cord showed a marked loss of fibers in patients 5 (g) and 10 (j), but they were relatively preserved in patient 7 (h), and fiber loss of the middle root zone in patient 2 (f) and 8 (i). a, f Patient 2 with pTDP-43-ir NCI. b, g Patient 5 with pTDP-43-ir NCI. c, h Patient 7 with FUS-ir NCI. d, i Patient 8 with FUS-ir NCI. e, j Patient 10 with SOD1-ir NCI, (Bar = 5 mm, Klüver–Barrera staining)