and loss of neurons, especially of pyramidal cells may be related, apparently, with the action of ethanol and drugs.
, or shrunken nuclei, are characterized by a small shrunken nucleus, with a high density of nuclear material that is uniformly but intensely stained.
Farley (1969) mentioned "increased sarcomatoid cell pyknosis
" in disseminated neoplasia of mussels that possibly referred to apoptotic chromatin condensation.
At the cellular level, the tubular cells showed pyknosis
and cytoplasmic lysis (Fig.
Apoptotic cell nuclei presented in dark brown, the cytoplasm showed no color and the cell nuclei showed pyknosis
. TUNEL-positive cells in the slices of each group could be seen in the light microscope.
On H&E-stained sections, neuronal pyknosis
, swelling, torsion, and cell body deformation were present in rat cortex of DAI 3 d group while, in the control group, no similar abnormal histopathological changes were observed (Figure 1).
Myocyte necrosis was identified in HE-stained sections under 400x magnification by nuclear pyknosis
and karyolysis as well as cytoplasmatic changes including vacuolization, contraction bands, and hypereosinophilia.
This form of cell death is fundamentally different from apoptosis and lacks some distinct characteristics of apoptosis such as DNA fragmentation, pyknosis
, or caspase activation and cleavage .
Later changes include necrotic changes (pyknosis
and karyorrhexis of trophoblast), loss of trophoblast nuclear staining, and eventually ghost villi.
However, the hippocampal neurons in the model group exhibited clear pyknosis
, nuclear invagination, karyorrhexis and increased numbers of lysosomes.
Terminal villi are small with irregular full-blooded capillaries coated with a single layer of thinned syncytium with focal nuclear pyknosis
. Capillary walls are thickened, with proliferating endothelium.
Our findings are also in accordance with Abdel-Gawad S K & Mohamed A K G (9) who observed that PCT was most severely affected followed by DCT in the form of vacuolated cytoplasm and necrotic changes in the form of nuclear pyknosis
along with intratubular casts with desquamated renal tubular cells.