Identification of Differentially Expressed Genes from Serum Deprived p388D1 Cells

This experiment is designed to find differentially expressed genes in p388D1 cells that are specific for the serum deprived state. Serum starvation induces cells to enter the quiscent state in the cell cycle and is used to arrest cell growth or synchronize the cell cycle. Differential display and ribonuclease protection assay were used to identify quantitative change in gene expression. Nineteen genes that showed a differential expression in the differential display were cloned and 7 clones were verified by a ribonuclease protection assay. Among the 7 clones clone-16 showed same expression pattern in comparison with the differential display. Deduced amino acid sequences of clone-16 had N-glycosylation motif and seems to be a secretory protein. Getting a full sequence of clone-16 is critical for the characterization of it.

Primary Ovarian Leiomyosarcoma: A case report

Primary leiomyosarcoma is a rare tumor of the ovary. We experienced a case of primary ovarian leiomyosarcoma in a 68 year old woman. Microscopically, the tumor was characterized by interlacing bundles of plump spindle cells that showed immunoreactivity for alpha-smooth muscle actin, pleomorphic multinucleated giant cells and an increased mitotic rate. Ultrastructural features included abundant smooth muscle type filaments and irregular bodies. Consequently, this case has led us to propose ultrastructural and immunohistochemical criteria for primary ovarian leiomyosarcoma.

HgCl2 Toxicity on Cultured Renal Tubular Cells of Rabbit

To understand the mechanism of cell injury when exposed to HgCl2, monitoring of cytosolic ionized free Ca2+([Ca2+]i), viability test, measurement of the amount of ATP, and Ca-ATPase activity were evaluated in cultured rabbit renal tubular cells(RTC) exposed to HgCl2. The results were as follows: 1) HgCl2 was cytotoxic to rabbit RTC at all doses except 10 uM and the rate of killing displayed a dose- and time-dependent relationship. 2) The absence of extracellular Ca provided partial protection from irreversible injury induced by HgCl2. 3) The increasing pattem of [Ca2+]i varied according to the concentrations of HgCl2. At the low concentrations of HgCl2 (2.5-10 microM), the level of [Ca2+]i increased slowly over the flat 2-3 min and then achieved plateau-state. In contrast, at the high concentrations of HgCl2 (25-100 microM) the level of [Ca2+]i achieved peak within 1 min and then decreased to a plateau state under normal concentrations. 4) The level of ATP was decreased to 27.5% of that of normal control cells within 3 min by using a treatment of 100 microM HgCl2. 5) HgCl2 did not affect the Ca2+ ATPase activity by enzyme histochemical observation. These findings suggest that the elevation of [Ca2+]i in response to the HgCl2-induced injury is an important event in accelerating injury that ultimately leads to cell death. But other possibilities such as HgCl2 might have direct deleterious effects on the also should be considered.

Production of PGE2 and H2O2 from Alveolar Macrophage Stimulated by Silica / 결핵

BACKGROUND: The pathogenesis of silicosis has been focused on the interaction between alveolar macrophages and silica particle. Although fibrosis in silicosis has been studied extensively, the mechanism is still not fully understood. There is increasing evidence that monokines and arachidonic acid metabolites produced by macrophage are involved in pathogenesis of silicosis. Recently, it was reported that prostaglandin E2 produced from macrophage counteracts the stimulatory effects of other monokines on fibroblast proliferation or collagen production. Until now, it was remained uncertain by which mechanism silica particle may activate alveolar macrophage to an enhanced release of prostaglandin E2. METHODS: In order to investigate the relationship between the activity of alveolar macrophage and the production of PGE2 from activated alveolar macrophage, the authors measured hydrogen peroxide and PGE2 from alveolar macrophages activated by silica in vitro and from alveolar macrophages in the silicotic nodules from rat. Experimental silicosis was induced by intratracheal infusion of silica(SiO2) suspended in saline (50 mg/ml) in Sprague-Dawley rats. RESULTS: 1) The silicotic nodules with fibrosis were seen from the sections of rat lung at 60 days after intratracheal injection with 50 mg aqueous suspension of silica. 2) In vitro, silica caused the dose dependent increase of hydrogen peroxide(p0.05) release from alveolar macrophages. Alveolar macrophages from rats with silicotic nodules released more hydrogen peroxide and PGE2 than those of control group(p<0.05). CONCLUSION: These results suggest that silica particle could activate macrophage directly and enhanced the release of PGE2 and hydrogen peroxide from the alveolar macrophage.

Acardiac Fetus with Encephalocele: A case report

The acardiac fetus is a rare type of fetal monster in which, as the name implies, the heart is completely absent. Acardius occurs only in a pair monozygotic twin, and shows various other defects in addition to the absence of the heart. Our autopsy case is acardiac anceps. He weighed 1,980 gm and the height was 33 cm. The brain is poorly developed, 60 gm in weight and similar to reversed snowman (3.5x2.8x2.8, 1.5x1.5x1.3 cm). Encephalocele, 6 cm in diameter, was communicated with the brain by a tract which contains nervous tissue and primitive choroid plexus. The upper extremities were absent, while the vertebrae and lower extremities were relatively well developed. The heart, lungs, stomach, liver, and spleen were absent, but the kidney, genital organs and urinary bladder were present. The intestine was seperated into two segments which were blindly ended, 32 cm and 15 cm in length, respectively.

Mutation of Adenomatous Polyposis Coli Gene in Human Stomach Cancer

Recently the adenomaatous polyposis coli(APC) gene, a tumor suppressor gene, was identified and the cDNA was cloned from chromosome 5q21. Allelic deletion or point mutation of tumor suppressor genes(TSGs) has been considered as an important mechanism in development of human tumor. Point mutations affecting APC gene are seen in the hereditary syndrome, adenomatous polyposis and spordic colon cancer. However, the mutation of APC gene and other TSGs have not been described in gastric cancer. In order to identify the mutation of exon 11 of APC gene for gastric cancer, we amplified DNA extracted from paraffin-embedded tissues by polymerase chain reaction(PCR) and digested the PCR products with restriction enzyme Rsa I. We examined the DNA extracted from paraffin-embedded 44 gastric cancer tissues with lymph nodes. Eighteen(41%) among 44 were informative for the study exon 11 of the APC gene, and we found loss of heterozygosity(LOH) for APC in 6/18(33.3%). These data suggest that the point mutation or the base change of APC gene commonly occurs in gastric cancer. We conclude that the mutation of APC gene is strongly connected with development of human gastric cancer.

The Rsa I polymorphic site within exon II of APC(adenomatous polyposis coli) gene determined by digestion of PCR products in human gastric cancer

No abstract available.

Loss of heterozygosity at the MCC and APC genetic loci in precancerous gastric lesion and gastric cancer / 대한암학회지

No abstract available.