• The Korean Journal of Malacology
• /
• v.14 no.2
• /
• pp.149-159
• /
• 1998

In order to observe the anticellulolytic localization in the epithelia of the digestive tract such as esophagus, crop, and intestine of a Korean land snail N. samarangae, a cytochemical method and a immunogold labelling method were applied. For the cytochemical study on the cellulase activity, Benedict reaction method applied. And for the immunocytochemical study, the rabbit serum immunoglobuins (IgG) was obtained from the rabbits injected with cellulase which was extracted from body fluid of the snail. The digestive tract tissues of N. samarangae were fixed with 4% paraformaldehyde and 2% OsO4 and embedded in Lowicryl K4M at -40$^{\circ}C$ under UV light (360 nm). The thin sections were loaded on the nickel grids and stained with the serum IgG and protein A-gold complex (particle size: 10 nm). Observations were undertaken with transmission electron microscope (Jeol, JEM-1010). The epithelium of the digestive tract was consisted of five types of cells. In the cytochemical study, the reaction products were found along the periphery of the vacuoles derived from the Bebedict reaction. In the immunocytochemical study, the protein-A gold particles were selectively labelled in Type 1, Type 3 and Type 4 cells in intestinal tissue. membranes of rER, in the surrounding cytoplasm of the rER and secretory granules, and in the apical cytoplasm of the cells. On the material being secreted from the apical cytoplasm was also labelled with the immunogold particles. The all results obtained throughtout present study suggest that the intestinal epithelium of the snail N. samarangae seretes cellulase as one of digestive enzymes.

• Journal of fish pathology
• /
• v.14 no.2
• /
• pp.91-95
• /
• 2001

Mass mortalities occurred among red drum larvae, 20 to 30 days old, culturing at hatcheries on southern costal area. No specific external signs were observed except abnormal swimming and spinal deformity. It was, however, suspected as a viral etiology due to high mass mortalities so that histopathological and molecular biological study was performed to evaluate the agent. Both vacuoles and necrosis were observed on nerve cells of brain and eye by H-E staining, and viral particles were observed on electronmicroscopic examination. On the other hand, DNA fragment, approximately 426 bps, was amplified with RT-PCR. The above results were able to diagnosis the etiological agent of mass moralities in red drum larvae as VNN(viral nervous necrosis)virus.

• Environmental Mutagens and Carcinogens
• /
• v.15 no.2
• /
• pp.122-130
• /
• 1995

In order to evaluate the cytotoxicity of lead in cultures of Balb/c mouse 3T3 cell line, various cytotoxic assays were carried out after expose cells to various concentrations of lead nitrate. Cytotoxic assays using this study were included NR assay, MTT assay, measurement of LDH and protein, synthetic rate of DNA and UDS. Intrace!!ular Ca$^{2+}$ level was also measured. Light and electron microscopic studies were done for morphological changes of lead-treated cell cultures. The results were as follows; 1. The absorbances of NR and MTT were decreased dose-dependently, and NR, and MTT, values of lead nitrate were 3.4 mM and 1.5 mM, respectively. 2. Amount of LDH released into the medium was increased in dose-dependently and LDH activity at 5 mM concentration of lead nitrate was increased to 335 % of control. 3. Amount of total protein was decreased dose-dependently, and which was half of control at 2 mM concentration of lead nitrate. 4. The synthetic rate of DNA was decreased dose-dependently, and also which was remarkably decreased at 3 mM and 5 mM concentrations of lead nitrate. 5. The synthetic rate of UDS was increased at 1 mM concentration of lead nitrate, but which was remarkably decreased at 3 mM and 5 mM concentrations of lead nitrate. 6. Intrace!lular Ca$^{2+}$ level was remarkably increased at 1 mM concentration of lead nitrate, compared with control. 7. In light microscopy, number of cells and processes were decreased according to the increase of dosage of lead nitrate. Electron microscopic findings showed that many vacuoles and cisternal dilatation of rough endoplasmic reticulum were seen in the cytoplasm at 1 mM concentration of lead nittale. From the above results, high dosage treatment of lead nitrate (>3 mM) damaged genetic malerials and it also showed cytotoxicity in mouse 3T3 cell line cultures by injury of cell organelles and Ca$^{2+}$ channel.

• Molecules and Cells
• /
• v.40 no.9
• /
• pp.643-654
• /
• 2017

Autophagy is a degradation pathway in eukaryotic cells in which aging proteins and organelles are sequestered into double-membrane vesicles, termed autophagosomes, which fuse with vacuoles to hydrolyze cargo. The key step in autophagy is the formation of autophagosomes, which requires different kinds of vesicles, including COPII vesicles and Atg9-containing vesicles, to transport lipid double-membranes to the phagophore assembly site (PAS). In yeast, the cis-Golgi localized t-SNARE protein Sed5 plays a role in endoplasmic reticulum (ER)-Golgi and intra-Golgi vesicular transport. We report that during autophagy, sed5-1 mutant cells could not properly transport Atg8 to the PAS, resulting in multiple Atg8 dots being dispersed into the cytoplasm. Some dots were trapped in the Golgi apparatus. Sed5 regulates the anterograde trafficking of Atg9-containing vesicles to the PAS by participating in the localization of Atg23 and Atg27 to the Golgi apparatus. Furthermore, we found that overexpression of SFT1 or SFT2 (suppressor of sed5 ts) rescued the autophagy defects in sed5-1 mutant cells. Our data suggest that Sed5 plays a novel role in autophagy, by regulating the formation of Atg9-containing vesicles in the Golgi apparatus, and the genetic interaction between Sft1/2 and Sed5 is essential for autophagy.

• Childhood Kidney Diseases
• /
• v.17 no.1
• /
• pp.13-18
• /
• 2013

Podocytopathy is glomerular lesions characterized by podocyte injury. It is observed in various glomerular diseases, but minimal change disease and focal segmental glomerulosclerosis (FSGS) are the prototypes. In this review, morphologic features of podocyte injury and subtypes of FSGS will be reviewed briefly. Effacement of podocyte foot processes is the most common feature of podocyte injury. As podocytic injury progresses, intracytoplasmic vacuoles, subpodocytic cyst, detachment of podocytes from the glomerular basement membrane and apoptosis develop. Glomerular capillary loops in epithelium-denuded area undergo capillary collapse. Synechia and hyalinosis may accompany this lesion. To manifest segmental sclerosis, podocyte loss above a threshold level may be required. Injured podocytes can injure neighboring intact podocytes, and thereby spread injury within the same lobule. FSGS can be categorized into five subtypes by morphologic characteristics; not otherwise specified (NOS), perihilar, cellular, tip, and collapsing types. Each subtype has been reported to show different clinical courses and associated conditions, but there are controversies on its significance. With recent progress in the discovery of genetic abnormalities causing FSGS and plasma permeability factors, we expect to unravel pathophysiology of FSGS and to understand histological sequences leading to FSGS in near future.

• The Korean Journal of Malacology
• /
• v.4 no.1
• /
• pp.1-16
• /
• 1988

The authors observed histochemical and ultrastructural characters on the osphradium of Rapana venosa Valenciennes using light microscope, scanning and transmission electron microscpes. The results were as follows:1)The basic structure of osphradium was bipectinated shape, which consisted of a septum situating in the center of osphradium and numerous osphradial leaflets. On the other hand, Epidermis of ospradial leaflets formed the structure of pseudostratified ciliated columnar epithelium which was composed of an epithelial cell layer, a basal cel layer and a neuropile. 2) Ciliated dpithelial cells:A large number of these cells were observed on the lateral and ventral regions but a small number of them were observed on the dorsal region. These cells had cylindrical microvilli, slender mitochondria and serve fibers.3) Supporting cells: These cells had cylindrical microvilli, spongy layer, electron dense granules, mitochondria and nerve fibers4) Four types secretory epothelial cells: Four distinct types of secretory epithelial cells were recognized and were arbitrily designated as Type I, Type II, Type III and Type IV.cell type I: These cells contained electron denwe granules(diameter, 0.94-1.56${\mu}{\textrm}{m}$), well developed Golgi apparatus and rough endoplasmic reticula, cell type II: These cills contained two types of granules of the different electron density. One was high electron density granules which were 0.4-1.0${\mu}{\textrm}{m}$ in diameter, The other was low electron density granules which were 0.75-1.2${\mu}{\textrm}{m}$ in diameter.cell type III:These cells had fibrous secretory materials and exhibited strongly positive reaction with Toluidine blue.cell type IV:A large number of this type of cells were observed on the ventral region of ospgradial leaflets and positively reacted with periodic acid Schiff reagent. 5)Dark cells contained several electron dense cillaty rootlets and unmerous granules but cellular organelles were not observed.6) Four types basal cells: Four distinci types of basal cells were recognized and arbitrarily designated as Type I, Type II, Type III and Type IV.Cell type I(light cell): These cells exhibited low electuon density and contained short smooth endoplasmic reticula, several vacuoles and granules.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6211-6216
• /
• 2012

Objective: To investigate the effects of gambogic acid (GA) on the growth of human malignant glioma cells. Methods: U251MG and U87MG human glioma cell lines were treated with GA and growth and proliferation were investigated by MTT and colony formation assays. Cell apoptosis was analyzed by annexin V FITC/PI flow cytometry, mitochondrial membrane potential assays and DAPI nuclear staining. Monodansylcadaverine (MDC) staining and GFP-LC3 localisation were used to detect autophagy. Western blotting was used to investigate the molecular changes that occurred in the course of GA treatment. Results: GA treatment significantly suppressed cell proliferation and colony formation, induced apoptosis in U251 and U87MG glioblastoma cells in a time- and dose-dependent manner. GA treatment also lead to the accumulation of monodansylcadaverine (MDC) in autophagic vacuoles, upregulated expressions of Atg5, Beclin 1 and LC3-II, and the increase of punctate fluorescent signals in glioblastoma cells pre-transfected with GFP-tagged LC3 plasmid. After the combination treatment of autophagy inhitors and GA, GA mediated growth inhibition and apoptotic cell death was further potentiated. Conclusion: Our results suggested that autophagic responses play roles as a self-protective mechanism in GA-treated glioblastoma cells, and autophagy inhibition could be a novel adjunctive strategy for enhancing chemotherapeutic effect of GA as an anti-malignant glioma agent.

• Korean Journal of Ichthyology
• /
• v.29 no.4
• /
• pp.252-257
• /
• 2017

The oogenesis of the Microphysogobio yaluensis was investigated using light microscopy. Various developmental oocytes appeared in the ovary of the M. yaluensis. The oogenesis is largely divided into four stages: nuclear-chromatin stage, peri-nucleoli stage, vitellogenesis (yolk vesicle and yolk granule stages), and mature stage. The nuclear-chromatin is distributed in a large germinal vesicle as threads. The peri-nucleoli stage has many acidic nucleoli lining at the inner side of the nuclear membrane and an egg envelope just weakly starts. As the oogenesis gradually proceeds, they change to the vitellogenesis stage. The oocyte become to drastically increase and the marginal area of the ooplasm is covered with many vacuoles showing no negative reactions with hematoxylin and eosin staining, called the yolk vesicle stage. Many yolk vesicles-owned oocyte largely increase and as the development continues, its ooplasm is changed from the yolk vesicles to the yolk granules of eosinophilic. At the mature stage, lots of granules merged into a big yolk mass, acidophilic. Even at the mature stage, the egg envelope was still thin between the ooplasm and the follicular layer of the oocyte.

• The Korean Journal of Cytopathology
• /
• v.6 no.2
• /
• pp.125-132
• /
• 1995

Cytodiagnosis of pleural and ascitic fluid is a commonly performed laboratory examination. Especially, positivity for malignant cells in effusion cytology is very effective and also presents the first sign of malignancy in unknown primary site of the tumor. We examined each 34 cases of pleural and ascitic fluid cytologic specimen diagnosed as metastatic tumor, which was selected among 964 pleural fluid cytology cases and 662 ascitic fluid cytology cases from September 1989 to June 1995. Among the pleural fluid cytology specimens examined, 34 specimens were positive in 27 patients. The lung was the most frequent primary site(44%), followed by the stomach (12%), lymphoreticular neoplasm(12%), pancreas(3%) and colon(3%). And the cases of unknown primary site with positive pleural biopsy alone were 24%. Among trio ascitic fluid cytology specimens examined, 34 specimens were positive in 29 patients. The most common primary neoplasms. were carcinomas of ovary(32%), stomach(22%), colon(6%), breast(3%), pancreas(3%), and lung(3%) and lymphoreticular neoplasms(3%) The metastatic tumor was predominantly adenocarcinoma type in both pleural(82%) and ascitic(91%) fluid. The study of metastatic adeno- carcinoma in effusion from lung, ovary, and stomach was undertaken to find distinctive features for the identification of the primary site. The smears of metastatic pulmonary adenocarcinoma had a tendency to show high grade pleomorphism and many large tight cell clusters, whereas that of the ovarian adenocarcinoma showed low grade pleomorphism with abundant intracytoplasmic vacuoles in relatively clear background. That of the stomach revealed the intermediate features.

• The Korean Journal of Cytopathology
• /
• v.10 no.1
• /
• pp.61-66
• /
• 1999

Angiosarcomas are rare tumors, seen most commonly in the skin and soft tissue of head and neck legion. But it has been described in numerous body sites including thyroid, breast, liver, spleen, bone, etc.. Their biological behaviors depend on the microscopic grade, site of origin, and multifocality. We report the unique cytological features of an angiosarcoma in pleural fluid. A 61-year-old woman presented with a 6 month history of dyspnea on exertion and chest pain. Chest computerized tomography(CT) revealed multiple subpleural small nodules in the right lung and widespread all space consolidation and pleural effusion in the left lung. CT of liver revealed multiple small low attenuated lesion. The smears obtained from pleural fluid showed hypocellularity with a hemorrhagic background. The tumor cells were highly pleomorphic oval or spindle in shape and presented singly, in loose groups, in knitted syncytial aggregates, and in acinar pattern. Their nuclei had vesicular chromatin with delineated, thick nuclear membranes and occasionally a large eosinophilic, prominent nucleolus. The cytoplasm was plump, thin or protected in spindly fashion. Almost ail tumor cells showed variable sized intracytoplasmic vacuoles and their nuclei were sometimes crescentic by a huge vacuole. Occasional binucleated tumor cells and mitotic figures were present. Cellular debris and streaky materials were identified. Needle biopsy specimen from the pleura revealed anastomosing slit-like spaces lined by pleomorphic tumor cells. The tumor cells showed a strong reactivity for CD31 and vimentin and focal weak reactivity for factor VIII-related antigen.