Table 1 NEC scoring system* in H&E staining and apoptosis scoring system* in TUNEL staining.

NEC scoring system

Score 0

Intact villi

Score 1

Sloughing of cells on villous tips

Score 2

Mid-villous damage

Score 3

Villi were absent, but crypts were still readily detectable

Score 4

Complete absence of epithelial structures and transmural necrosis

Apoptosis scoring system

Score 0

The villous epithelium was continuous, only solitaire TUNEL positive nuclei

Score 1

Clusters of TUNEL-positive nuclei on the villous tips

Score 2

Apoptotic nuclei covering the villous,

but crypts were completely spared from apoptosis

Score 3

Apoptosis penetrating into the crypts

Score 4

Transmural distribution of TUNEL –positive nuclei