The purpose of this study was to investigate the inhibitory role of vitamin A with respect to activation of Ito cells in fibrosis of the rat liver induced by common bile duct ligation(CBDL). The liver was examined by immunohistochemical staining for a-smooth muscle actin,the known marker of activated Ito cells, and light and electron microscopy after CBDL andCBDL with intraperitoneal injection of retinoic acid (Sigma, USA) 1 mg/Kg in 3 times per week. The results were sumrrlerized as follows: After CBDL, the bile ductules were markedly proliferated in the periportal areas extending toterminal hepatic veins. Interstitial fibrosis and inflammatory cell infiltration appeared, however,cholestasis was minimal. Retinoic acid treatment with CBDL decreased bile ductular proliferationand interstitial fibrosis compared to CBDL only. After CBDL, proliferated and activated Ito ceIs showing positive reaction in smooth muscle actin were present in the periductular andperisinusoidal areas, and areas of increased interstitial fibrosis. Activated ito cells weredecreased in number after CBDL with vitamin A treatment. Electron microscopically,intracytoplasmic fat droplets and the cytoplasmic processes of Ito cells were decreased afterCBDL. Myofibroblasts were frequently appeared in the interstitial fibrosis after CBDL. But,intracytoplasmic fat droplets of Ito cells were well preserved, and myofibroblasts were found lessfrequently after CBDL with vitamin A treatment. The results suggest that vitamin A plays an inbitory role in the activation and fibrogenesis ofIto cells after CBDL.
Rats ; Animals

Myeloid body formation is an ultrastructural feature of gentamicin induced nephrotoxicity in human being and experimental animals. The origin of the myeloid body is not satisfactorily understood and morphological verification of the developing process of this structure is not fully accomplished. We injected 100 mg/kg/12 hour of gentamicin in 20 Spraque-Dawley rats and examined the ultrastructural feature of the proximal convoluted tubular cells of the kidney every 30 minutes in the first 4 hours, and in 5 hours, 6 hours, 12 hours, 24 hours and 48 hours after injection of gentamicin, with a TEM and a SEM. Myeloid bodies were noted as concentric layers of membranous structures of degenerated endoplasmic reticulum and mitochondria in the lysosome. The number and size of the myeloid body containing lysosomes were increased with time. We can deduce from this observation that injured cell organelles by diffusible gentamicin within the cells are autophagocytosed by lysosomes which were also injured by the drug from pinocytotic vesicles, and incompletely digested organellar remnants are retained in the lysosomes as myeloid bodies. So we think that the myeloid body formation is a result of an exaggerated and a pathologic autophagocytic process due to cell injury induced by gentamicin.
Animals ; Endoplasmic Reticulum ; Gentamicins* ; Humans ; Kidney ; Lysosomes ; Mitochondria ; Organelles ; Rats*

PURPOSE: Introduction of shock wave lithotripsy has provided an avenue for dealing with many urinary stones noninvasively. Although shock wave is known to cause pathologic changes in various organ, little is k nown about its effect on the ureter and recovery after shock wave, the target organ in SWL of injury induced by shock wave and the potential protective effect of allopurinol and nifedipine against shock wave. MATERIALS AND METHODS: A total 24 rabbits were assigned to 2 groups. 12 rabbits received allopurinol(10mg.each) and nifedipine (1mg.each) that were given orally 3 times a day for 5 days starting the night before SWL. The other 12 rabbits reseived no medication. The left lower Ureter segments of 24 rabbits were removed ureter. Groups of 8 rabbits(4were medication group and 4, no medication group) were sacrificed 1, 3 and 5 days after shock wave exposure. The histomorphological alterations were examined under light and transmission electron microscopy. RESULTS: The epithelial cells disclosed no change after shock wave application. Histologically the muscular layer was the most affected part of ureter. There was interstitial and intracellular edema on light microscopy and made chromatin and mitochondrial changes at the subcellular level. The adventitial layer wes also edematous. This chanfes were prominent on day 1and 3 and returned to normal on day 5. The medication group showed less severe features of injury, compared with the no medication group. CONCLUSIONS: Electromagnetic shock waves produce reversible morphological changes in rabbit ureteric muscle and allopurinol and nifedipine may have its role in protecting the tissue injury produced by high energy shock waves.
Allopurinol* ; Chromatin ; Edema ; Epithelial Cells ; High-Energy Shock Waves ; Lithotripsy ; Magnets ; Microscopy ; Microscopy, Electron, Transmission ; Nifedipine* ; Rabbits ; Shock* ; Ureter* ; Urinary Calculi

Lipomas of the heart are benign neoplasms and have rarely been described. Due to the fact that they normally cause no symptoms, diagnosis is often purely accidental. Because of the rarity of these tumors, it seems worthwhile to present an example studied at autopsy. It was associated with the sudden death of a 15-year-old boy. The tumor arose from the wall of the left ventricle and occupied the pericardial cavity, measuring 13x7x6 cm in size. The tumor was whitish-yellow, translucent, and soft. Microscopically, the tumor was composed of mature adipose tissue which extended between muscle fibers. This current case, the giant cardiac lipoma is believed to produce disturbances of the conduction system and distrubances of cardiac filling.

We describe an ovarian mucinous cystadenocarcinoma with a sarcoma-like mural nodule. In the literature, rare cases of ovarian mucinous tumors have been described which contain foci of undifferentiated carcinoma, sarcoma, and sarcoma-like nodules. The distinction between these lesions is important because of poorer prognosis of true sarcoma and anaplastic carcinoma than sarcoma-like mural nodules. This case shows different results of immunohistochemical stain for anaplastic carcinoma.

Ameloblastic fibrosarcoma is an extremely rare variety of odontogenic tumor. It has not previously been reported in Korea. The tumor is composed of benign odontogenic epithelium with a mesenchymal part which exhibits the histologic features of fibrosarcoma. We have reported a case of amloblastic fibrosarcoma of the mandible in a 26-year-old man with swelling of right mandible for 2 weeks. The tumor showed yellowish ill-demarcated ulcerating mass involving right premolar and molar area. Light microscopy revealed irregularly arranged strands and islands of odontogenic epithelium surrounded by abundant mesenchymal tissue with the feature of fibrosarcoma. The fibrosarcoma cells were strong positive on immunostain for vimentin and ameloblastic cells were weakly positive for cytokeratin. S-100 and CEA were negative in both epithelial and sarcoma cells. The sarcoma cells were corresponding to fibroblasts on the electron microscopy with abundancy of RER and mitochondria and covering of basal lamina. Two types of virus like particles were distributed in the cytoplasm and nuclei of sarcoma cells. We treated the patient with surgery and chemotherapy. The recovery was uneventful and the prognosis is under observation.
Male ; Humans

The purpose of this study is to investigate the morphologic changes of the sinusoidal endothelial cells and the associated structures of the cirrhotic rat liver induced by repeat intraperitoneal injections of N-diethylnitrosamine (DEN) (100 mg/kg/week). One day to 6 weeks later, rat livers were observed under the light, transmission and scanning electron microscopy, and immunostained with laminin antibody. Two weeks after DEN treatment, the fibrillar material in Disse's space was noted, and then a basement membrane-like structure was found at 4 weeks after treatment. Laminin was detected in perisinusoidal areas after 4 weeks. Laminin was strongly positive on the fibrous septum and in the sinusoidal wall of cirrhotic nodules after 6 weeks of treatment. The diameters and numbers of sinusoidal endothelial fenestrations did not change significantly until 2 weeks. They decreased within 4 weeks, and then the sinusoidal endothelium was poorly fenestrated at 6 weeks after DEN treatment. These results suggest that as fibrosis develops in cirrhosis, the deposit of extracellular matrix such as laminin within Disse's space is a major contributing factor in the structural alteration of sinusoidal endothelial cells, and the capillarization of the sinusoidal endothelial cells may be a contributor to impairment of the hepatic function in cirrhosis.
Rats ; Animals

Morphological changes of hepatic microcirculation, especially in the peribiliary plexus, in cirrhotic livers of rats induced by repeated intraperitoneal injections of N-diethyinitrosamine (DEN) (100mg/kg/week) were studied by scanning electron microscopy. Control rats were treated with saline. The livers were perfused with saline and injected with methyl-methacrylated resin (Mercox CL-2B) through the thoracic aorta. Diffuse nodular changes mimicking human cirrhosis were seen in the livers six weeks after injections of DEN. The cirrhotic livers showed an increase of vascular channels composed mainly of venous branches around the regenerating nodules and increased arterioloportal anastonloses. Peribiliary plexi of the cirrhotic livers had more vessels than those of the controls. Many dilated veins and ramificating portal vein branches were also Present. Direct connections between peribiliary plexi and sinusoids or between peribiliary plexi and portal veins were increased in the cirrhotic liver. These results suggest that the peribiliary plexi in experimentally induced cirrhotic liver might play a role in a collateral circulation under a state of portal hypertension.
Humans ; Rats ; Animals

The purpose of this study was to investigate the morphologic changes of the bile canaliculi and its associated structures of the liver induced by common bile duct ligation(CBDL) in the rat. The canalicular surface and lateral surface of the dry-fractured hepatocytes was studied with scanning electron microscopy at 1~6 weeks post ligation. The first week after CBDL, the bile canaliculi were dilated. The microvilli were increased in number and the lumens contained granular materials After 2 weeks or more, the bile canaliculi were dilated to a variable degree, and with irregularity, measuring from 1.5 to 5 micrometer in diameter, and in the advanced stage, the canaliculi showed blunting and the disappearance of microvilli. Some canaliculi had sprouting side branches. At 4~6 weeks post-ligation, the lateral surface of the hepatocytes also showed some irregularity and a tortuous appearance, and numerous small sized microvillous projections were formed. The tubular structures of the proliferated SER distributed adjacent to the lateral surface of the hepatocytes, and the direct connection of a tubular structure and the cytoplasmic membrane was observed. These results suggest that the deformity and loss of microvilli of bile canaliculi reflect the disturbance of bile secretion from the hepatocytes. And prolonged obstruction of bile flow may result in bile excretion via the lateral surface of hepatocytes.
Rats ; Animals

Thirty three cases of metastatic ovarian carcinoma were analysed cilincopathologically. The patient's age ranged from 20 to 68 years, the average being 44.3. Most ovarian tumors were bilateral and asymmertically enlarged, firm and occsaionally multicystic. Histologic examination revealed adenocarcinoma in 31 cases, of which Krukenberg tumors in 14; squamous cell carcinoma in 2. The most common primary site was gasrtointestinal(75.8%), followed by genital, breast and gallbaldder. Most Krukenberg tumors were originated from poorly differentiated adenocarcinoma of stomach. The ovarian and primary carcinomas were synchronously diagnosed in 15 cases, while in 3 cases the primary carcinoma was not round until the ovarian tumor had been removed.
Adenocarcinoma ; Neoplasm Metastasis