BACKGROUND: There is a long-standing controversy whether melanocytes in vitiligo of more than 1 year duration are actually lost or still present. Resolving this matter is essential in understanding the underlying pathology and for the development of the treatment. On previous immunohistochemical and ultrastructural studies of vitiligo lesions, damage of melanocyte and keratinocyte in early lesions were reported and complete absence of melanocyte in long standing lesions were known. OBJECTIVE: This study aimed to determine the existence of the differences in pathologic changes in melanocytes according to the duration of the lesion. METHODS: We investigated the vitiliginous skin samples from 31 patients with early(less than 1 year duration) vitiligo and 30 patients with long standing(l to 5 years duration) vitiligo under the electron microscopy. RESULTS: Multiple degenerative changes in melanocytes were observed in the early and long standing lesions. In long standing lesions, degeneration of melanocytes including pyknotic, in-dented nuclei, vacuolated cytoplasms and blunted dendrites were more pronounced than early lesions. Even in long standing lesions, definite or presumptive melanocytes were observed in 16(53.3%) of 30 cases. CONCLUSION: Our results suggest that the melanocytes of vitiligo lesions were damaged and that the percentage of degenerative changes increase in accordance with the duration of the lesion. However, in long standing lesions as well as in early lesions, some residual melanocytes can be observed ultrastructurally.
Cytoplasm ; Dendrites ; Humans ; Keratinocytes ; Melanocytes ; Microscopy, Electron ; Pathology ; Skin ; Vitiligo*

OBJECTIVETo investigate the mitochondrial injury in enterovirus 71 (EV71)-infected Vero cells and explore the possible mechanism.

METHODSA clinical isolate of EV71 was inoculated to Vero cells and the EV71 antigen was detected by immunofluorescence assay. The morphological changes of Vero cells were observed using optical microscopy and transmission electron microscopy. The diameter and area density of the viral particles and the ratio and area density of vacuolated mitochondria in the cells were measured on the ultrastructural images.

RESULTSEV71-infected Vero cells underwent obvious changes and to a spherical morphology followed by cell death EV71 particles were detected in the cytoplasm by immunofluorescence. Ultrastructurally, the infected cells contained a large number of viral particles in the cytoplasm, with a clustered distribution and lattice-like arrangement. The diameter of the particles were 16.3 nm and the mean area density was 38.3%. Most of the mitochondria presented with swelling, vacuoles and degeneration. The ratio of the vacuolated mitochondria was 90.9% with a mean area density of 89.2%. Viral particles were also found in some mitochondria.

CONCLUSIONEV71 proliferates in the cytoplasm and invades the mitochondria of infected Vero cells leading to mitochondrial injury and cell death, suggesting that mitochondria are the targets for EV71 infection.

Animals ; Cercopithecus aethiops ; Cytoplasm ; virology ; Enterovirus ; Enterovirus Infections ; pathology ; Humans ; Mitochondria ; pathology ; virology ; Vero Cells ; virology

Aged ; Cytoplasm ; Cytoplasmic Granules ; Female ; Humans ; Multiple Myeloma ; pathology ; Plasma Cells ; pathology

To investigate the morphological changes of megakaryocytes with nuclear extrusion and nucleocytoplasmic separation, the morphological characteristics of megakaryocytes in peripheral blood films, bone marrow smears, and bone marrow biopsies from 4 newly diagnosed patients with primary myelofibrosis (PMF), myelodysplastic syndrome (MDS), myeloblastic leukemia with maturation (M(2)) and erythroleukemia (M(6)) were studied by using light microscope. The results showed that many kinds of dysmegakaryocytes were observed in bone marrow smears of 4 cases, while in case A (PMF) and case D (M(6)) micromegakaryocytes were ripped apart; in case B (MDS) and case C (M(2)) megakaryocytes were accompanied by nuclear extrusion or nucleocytoplasmic separation, and their bodies were large or giant, the part of nucleus separated from their body and little cytoplasm remained as micromegakaryocytes. The nucleocytoplasmic separation could be displayed by immunocytochemistry stain. It is concluded that the phenomenon of nuclear extrusion and nucleocytoplasmic separation in megakaryocytes suggested the process that dispersed multinuclear releasing towards surround or even totally left the cell body during the megakaryocyte maturation. It also showed that the micromegakaryocytes may be the result of nucleocytoplasmic separation or splittings from multi-separated nucleus.
Aged ; Bone Marrow Cells ; pathology ; Cell Nucleus ; pathology ; Cytoplasm ; pathology ; Female ; Hematologic Diseases ; blood ; Humans ; Male ; Megakaryocytes ; pathology ; Middle Aged

Renal oncocytoma is an epithelial tumor of the kidney with a particularly good prognosis and is composed entirely of uniform packets of eosinophilic granular cells so-called 'Oncocytic cells' The cytoplasm of the oncocytoma cells is packed with mitochondria and contains few other organelles. At present time 4 cases have been reported in Korean literature without any identifiable angioinvasive lesions. We report a case of renal oncocytoma associated with angioinvasion that was suspected preoperatively and confirmed by pathologic examination including electron microscopy postoperatively. The pathology, diagnosis and treatment of this uncomrnon entity is discussed.
Adenoma, Oxyphilic* ; Cytoplasm ; Diagnosis ; Eosinophils ; Kidney ; Microscopy, Electron ; Mitochondria ; Organelles ; Pathology ; Prognosis

Renal dysplasia is a developmental disorder of the renal parenchyma involving anomalous differentiation. It is characterized by persistent metanephric ducts surrounded by primitive mesenchyme, fetal or immature glomeruli, fetal or immature tubules, interstitial fibrosis, and dysontogenic metaplasia involving tissues such as cartilage. Renal dysplasia has been rarely reported in rats. Here, we observed a small left kidney in a rat used in a short-term repeat toxicity study. The rat showed no clinical signs throughout the study. All parameters, including those reflecting kidney functions, were normal upon hematological examination and urinalysis. Grossly, the kidney was small (5 x 8 mm) and its surface appeared normal. Histological examination revealed that the cortex and medulla were poorly demarcated and contained immature/atrophic glomeruli, immature renal tubules, and mesenchymal cells. The cortex contained immature glomeruli, atrophic glomeruli with cystic dilatation of Bowman's capsular space, and some atypical tubules. Primitive metanephric tubules in the medulla were larger in diameter than normal collecting ducts, lined by a tall columnar epithelium with pale cytoplasm and basal nucleus, and surrounded by loose mesenchymal cells. Occasional tubules contained pale eosinophilic homogenous material in the lumen. Thus, this was diagnosed as a case of renal dysplasia on the basis of histologic features and is the first reported case of renal dysplasia in Sprague Dawley rats.
Animals ; Cartilage ; Cytoplasm ; Dilatation ; Eosinophils ; Epithelium ; Fibrosis ; Kidney ; Mesoderm ; Metaplasia ; Pathology ; Rats* ; Rats, Sprague-Dawley ; Urinalysis

Morphological studies have an important role in establishing the timing of irreversible damage occurred in cryptorchid testis. The present study was undertaken to determine how soon definitive sign or testis pathology may appear in cyptorchid testis. Testicular biopsies were collected at the time of orchiopexy from 79 patients during the period from January, 1988 to June, 1990, and then we examined ultrastructural changes of cryptorchid testis with light and electron microscopy. Comparing with normal testis, following results were obtained ; l. The volume of cryptorchid testis became smaller than normal after age of 14. 2. Mean tubular diameter became smaller after age of 14 and basement membrane thickened prominently after age of 20. 3. The increase number of mitochondria appeared at age of 2 4. Cytoplasmic vacuolization became prominent after age of 6, but detachment and loss of ribosome appeared at age of 20. 5. Tunica propria showed marked thickening and collagenous degeneration after age of 14. With above results, we suggest that orchiopexy should be done before age of 2.
Basement Membrane ; Biopsy ; Collagen ; Cytoplasm ; Humans ; Microscopy, Electron ; Mitochondria ; Orchiopexy ; Pathology ; Ribosomes ; Testis*

Based on 16 cases of human sparganosis, a histopathological study was made. There was a striking similarity among histological features of sparganosis involving different tissues. The histological change of the affected tissues was characterized by a necrotizing and granulomatous inflammation with or without worm parasite in the lesions. There was also a remarkable polymorphonuclear leukocytic mobilization, predominantly of eosinophils, plasma cells and lymphocytes in and near the lesions. Tunnel formation lined by palisading histiocytes was another charateristic feature of the host tissue reaction. These findings were quite distinguishable from those of cysticercosis which were more localized and self-limited. Several features that were prominent in section slides of sparganum worm parasite were also noted. Laminated calcospherules found in the cytoplasm of the proliferating macrophages and giant cells were of diagnostic value of sparganosis in the absence of the worm, particularly when these were accompanied with tunnel-like lesion in the host tissue.
parasitology-helminth-cestoda ; Spirometra sp. ; sparganum ; spaganosis ; histology ; pathology ; case ; cytoplasm ; macrophages ; giant cell

Animals ; Cytoplasm ; ultrastructure ; Fibroblasts ; ultrastructure ; Fractures, Bone ; pathology ; Microscopy, Electron ; Osteoblasts ; ultrastructure ; Rabbits ; Wound Healing

Histochemical, immunohistochemical and ultrastructural studies were performed on cases of hepatocellular carcinoma (HCC) with pale bodies (PB). HCC containing PBs was observed in 3 (5.5%) of 55 consecutively resected HCC cases. Histologically, a large number of hepatocytes displayed pale or eosinophilic staining of the cytoplasm, resulting in ground-glass appearance. They were aggregated in nodular pattern, or diffusely intermixed with other malignant hepatocytes. PBs were negative for periodic-acid Schiff and Masson's trichrome staining. The inclusions showed a strong positive reaction for fibrinogen and some of them were weakly positive for albumin but negative for hepatitis B surface antigen, hepatitis B core antigen, alpha-fetoprotein and alpha-1-antitrypsin. Ultrastructurally, PBs were membrane-bound and contained granular materials of moderate electron density, and were closely related to dilated rough endoplasmic reticulum. These findings support that PBs are secretory fibrinogen accumulated in cystic ER and that such intracellular accumulation possibly reflects a defective transport of fibrinogen.
Albumins/analysis ; Carcinoma, Hepatocellular/pathology* ; Cytoplasm/ultrastructure ; Cytoplasm/pathology ; Cytoplasm/chemistry ; Endoplasmic Reticulum, Rough/ultrastructure ; Endoplasmic Reticulum, Rough/pathology ; Endoplasmic Reticulum, Rough/chemistry ; Fibrinogen/analysis ; Human ; Inclusion Bodies/ultrastructure ; Inclusion Bodies/pathology* ; Inclusion Bodies/chemistry ; Liver Neoplasms/pathology* ; Male ; Microscopy, Electron ; Middle Age ; Periodic Acid-Schiff Reaction