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S T Oh

Publications and source records attributed to S T Oh.

29 records · Page 2Linked to original sources
PubMed1997

Calcium release from intracellular stores and excitation-contraction coupling in intestinal smooth muscle.

Calcium release from intracellular stores plays a central role in excitation-contraction coupling of striated and smooth muscle cells. Two main intracellular calcium pools have been identified in phasic smooth muscle: (1) the inositol 1,4,5-trisphosphate-sensitive and the (2) ryanodine-sensitive calcium stores. We studied the contribution of the ryanodine-sensitive calcium stores to the excitation-contraction coupling in the intestine. The intracellular calcium concentration was measured in cultured intestinal smooth muscle cells using the fluorescent probe fura-2-AM. Isometric tension generated by the murine jejunum was recorded in vitro using force displacement transducers. The cytosolic calcium level increased significantly on cholinergic stimulation. The rise persisted in the absence of extracellular calcium. Depletion of ryanodine-sensitive calcium stores with caffeine or ryanodine blunted the response to a cholinergic agonists. Similarly, the ryanodine receptor channel blocker dantrolene significantly decreased the carbachol-induced calcium increase. We subsequently tested the effects of these pharmacological tools on the spontaneous and carbachol-induced contractions of the murine jejunum. Depletion of the ryanodine-sensitive stores and calcium release channel block both significantly decreased the contractile activity of the circular and longitudinal layer of the muscularis propria. Our data confirm the importance of intracellular calcium stores in excitation-contraction coupling of intestinal smooth muscle cells. The effects of different pharmacological tools on the intracellular calcium signal and the contractile function are consistent with other observations in phasic smooth muscle. They suggest a significant contribution of calcium release from ryanodine-sensitive stores to the calcium signal that triggers contraction.

Animals↗
PubMed1996

Tubal patency and conception rates with three methods of laparoscopic terminal neosalpingostomy.

STUDY OBJECTIVE: To determine the best method of laparoscopic neosalpingostomy for terminal tubal obstruction with respect to postoperative tubal patency and pregnancy. DESIGN: Three-year follow-up study. SETTING: University hospital. PATIENTS: Eighty-two women. INTERVENTIONS: Clubbed fimbriae were incised with scissors and sutured after eversion in 26 patients (type 1 procedure), and incised with needle diathermy and everted by endocoagulator without suturing in 27 (type 2). In 29 women the original fimbrial shape was restored by traction with grasping forceps after making a small hole with needle diathermy, and the fimbriae were sutured after eversion (type 3). MEASUREMENT AND MAIN RESULTS: Tubal patency rates on hysterosalpingogram 2 months after the three operations were 13 (50%) of 26 patients for type 1, 23 (85.1%) of 27 patients for type 2, and 28 (96.2%) of 29 patients for type 3. Tubal patency for types 2 and 3 was significantly higher than for type 1 (p <0.01). Conception rates within 3 years for the procedures were 5 (19.2%) of 26 women for type 1, 10 (37.2%) of 27 for type 2, and 14 (48.2%) of 29 for type 3. The conception rate for type 3 was significantly higher than that for type 1 (p <0.05). Especially when the operation was performed in women with favorable prognostic conditions, the conception rate was 9 (64.3%) of 14 women for type 3 operation. CONCLUSIONS: The type 3 procedure was the most effective method of laparoscopic neosalpingostomy for terminal tubal obstruction, especially when performed in patients with favorable prognostic factors.

Adult↗
PubMed1994

Prenatal ultrasonographic diagnosis of congenital kyphosis due to anterior segmentation failure.

A few cases of congenital scoliosis due to segmentation failure have so far reported and the antenatal detection of pure congenital kyphosis without scoliosis due to segmentation failure has not been reported. We report the first prenatal identification using ultrasound of a fetus affected with pure congenital kyphosis due to anterior segmentation failure of the vertebral body between the second and third lumbar spine which was associated with ventriculomegaly, cleft palate, and hydramnios.

Adult↗
PubMed1994

The prognostic significance of c-erbB-2 and p53 protein expressions in gastric carcinoma--a multivariate analysis of prognostic factors.

152 curative gastrectomy specimens from patients with gastric carcinoma were examined in an attempt to assess the prognostic value of c-erbB-2 and mutant p53 protein expressions. The labeled streptavidin-biotin method was applied to routinely fixed and paraffin-embedded tissue sections, using the polyclonal and monoclonal antibodies against the c-erbB-2 protein and the mutant form p53 protein, respectively. In this examination, staining of c-erbB-2 protein was found in 9.2% of these carcinomas. The c-erbB-2 stained tumors were significantly associated with the tumors whose diameters were smaller than 5cm, and were more likely to be associated with serosal invasion and nodal involvement than the unstained ones. However, there was little association between staining of c-erbB-2 protein and clinicopathologic findings such as age, sex, location, histology, gross type, lymph node status, depth of invasion, and stage. The survival analysis of 104 patients with stage III gastric carcinoma revealed no significant association between c-erbB-2 staining status and survival duration. The 5-year survival rates of the c-erbB-2 positive group and its negative group were 21% and 28%, respectively. Positive p53 protein expression was observed in 46% of 152 carcinomas. There was no significant association between p53 expression and parameters such as age, sex, location, histology, gross type, and size. The p53 stained tumors were more likely to be associated with lymph node metastasis, serosal invasion than p53 unstained ones; but this did not reach significance. The 5-year survival rates of the p53 positive group and counter part group were 27% and 31%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

The effect of growth factors on the proliferation of human endometrial stromal cells in culture.

OBJECTIVE: Development of ectopic implants of endometriosis is associated with both an inflammatory response by macrophages and endometrial stromal cell proliferation. Macrophages are capable of releasing a variety of inflammatory mediators, including growth factors. To assess the impact of such factors on endometrial tissue, we have studied the effects of recombinant growth factors, fibroblast growth factor, epidermal growth factor, transforming growth factor-alpha, and inflammation mediators transforming growth factor-beta, and tumor necrosis factor-alpha on human endometrial stromal cell proliferation. STUDY DESIGN: Increasing concentrations of these compounds were added to cultures of primary, secondary, and long-term stromal cells and the cells were harvested at 24, 48, and 72 hours. RESULTS: Epidermal growth factor, transforming growth factor-alpha, transforming growth factor-beta, and fibroblast growth factor induced a statistically significant, dose-dependent increase in stromal cell thymidine uptake of 1.5- to fivefold. The cytokine tumor necrosis factor had no effect alone, but the combination of fibroblast growth factor and tumor necrosis factor had a synergistic effect, increasing cell proliferation 25% to 84% over fibroblast growth factor alone. CONCLUSION: The stromal cell response to a wide range of cell growth effectors and the potential of mediators like tumor necrosis factor-alpha to synergize suggest that such macrophage-secretory products may contribute to proliferation of endometrial implants in vivo.

Cell Division↗
PubMed1993

Treatment failure in malignant gestational trophoblastic disease.

One hundred and thirty-three patients with malignant gestational trophoblastic disease (GTD) were admitted. All patients (86/86) of the nonmetastatic and metastatic low-risk groups and 89.4% (42/47) of the metastatic high-risk group showed remission. The overall remission rate was 96.2%. Among 5 patients with brain metastases, however, only one (20%) survived. We arrived at two main conclusions. First, brain metastatic lesions did not successfully respond to therapy utilizing conventional chemotherapeutic regimens. Second, the key factors for successful outcome in brain metastases were early diagnosis and aggressive initial therapy. Therefore, early detection of brain metastases should be made with: (1) fine computerized tomography (CT) or magnetic resonance imaging (MRI), (2) measurement of the ratio of serum to cerebrospinal fluid hCG concentration, and (3) early recognition of their clinical features.

Adult↗
PubMed1992

Is the new UICC staging system of gastric cancer reasonable? (Comparison of 5-year survival rate of gastric cancer by old and new UICC stage classification).

In the new UICC TNM system for gastric cancer approved in 1985, a T1 lesion with lymph node (LN) metastasis is classified as stage, Ib; in the old TNM system this was classified as stage III. This is contradictory to a general rule of the UICC TNM system, whereby cancer with LN metastasis is classified as stage II or III. Two thousand and sixty-three patients with less than T4 gastric cancer who were treated at Seoul National University Hospital from 1970 to 1986 were analysed for significant prognostic factors. Survival curves were subsequently analysed according to the number of LN metastases and the depth of invasion. As a result of multivariate study for clinical and pathological features such as age, tumour location, gross appearance, histological type, depth of tumour invasion and regional lymph node metastasis, we confirmed that only two factors--regional lymph node metastasis and depth of gastric wall invasion--are significant. We showed that when the LN variable is classified according to the number of LN metastases (0 group, 1-3 group, > 3 group) like the UICC TNM classification of colorectal cancer, the survival curves are similar to those reported by the Japanese Research Society for Gastric Cancer. The authors propose the modification of the UICC TNM classification system according to depth of invasion and the number of LN metastases, whereby a T1 lesion with LN metastasis is classified as stage IIa instead of stage 1b.

Adenocarcinoma↗
PubMed1992

Results of surgery on 6589 gastric cancer patients and immunochemosurgery as the best treatment of advanced gastric cancer.

Results of 6589 gastric cancer operations at the Department of Surgery, Seoul National University Hospital, from 1970 to 1990 were reported. About two thirds (76.6%) were advanced gastric cancer (stages III and IV). The 5-year survival rate of operated stage III gastric cancer was only 30.6%, with frequent recurrence. Conversely, cell-mediated immunities of advanced gastric cancer patients were significantly decreased. Therefore, to improve the cure rate and to prevent or delay recurrence, curative surgery with confirmation of free resection margins and systematic lymph node dissection of perigastric vessels were performed and followed by early postoperative immunotherapy and chemotherapy (immunochemosurgery) in stage III patients. To evaluate the effect of immunochemosurgery, two randomized trials were studied in 1976 and 1981. In first trial, 5-fluorouracil, mitomycin C, and cytosine arabinoside for chemotherapy and OK 432 for immunotherapy were used. The 5-year survival rates for surgery alone (n = 64) and immunochemosurgery (n = 73) were 23.4% and 44.6%, respectively, a significant difference. In the second trial, there were three groups: group I, immunochemosurgery (n = 159); group II, surgery and chemotherapy (n = 77); and group III, surgery alone (n = 94). 5-Fluorouracil and mitomycin C for chemotherapy and OK-432 for immunotherapy were administered for 2 years. The 5-year survival rate of group I was 45.3%, significantly higher than the 29.8% of group II and than the 24.4% of group III. The postoperative 1-chloro-2.4-dinitrobenzene test, T-lymphocyte percentage, phytohemagglutinin- and con-A-stimulated lymphoblastogenesis and the antibody-dependent cell-mediated cytotoxicity test showed more favorable values in the immunochemosurgery group. Therefore, immunochemosurgery is the best multimodality treatment for advanced gastric cancer.

Anastomosis, Surgical↗
PubMed1992

Interleukin-1 inhibits growth of normal human endometrial stromal cells.

OBJECTIVE: To understand growth regulation of the endometrium by studying the effect of interleukin-1 beta (IL-1) on human endometrial stromal cell proliferation in vitro. METHODS: Endometrial stromal cells from human endometrium were separated and purified and placed in culture. Fresh and first- and sixth-passage cells were incubated with IL-1 (0.025, 0.25, and 2.5 ng/mL) for 24, 48, and 72 hours, respectively. Proliferation as a function of DNA synthesis was assessed by measuring 3H-thymidine incorporation. Experiments were then repeated in the presence of indomethacin to determine whether IL-1 effects were dependent upon prostaglandin synthesis. We evaluated overall growth by adding IL-1 to cell cultures of sixth-passage stromal cells every 3 days and by performing cell count studies. RESULTS: Interleukin-1 beta significantly inhibited 3H-thymidine uptake in freshly explanted endometrial stromal cells at all doses in a dose-dependent manner; a 44% inhibition was seen at 2.5 ng/mL IL-1 after 72 hours of incubation. In first- and sixth-passage cells, 3H-thymidine uptake was inhibited only at intermediate and high doses of IL-1. Cell count studies showed that sixth-passage cells were significantly inhibited by IL-1 after 23 days of growth (22%; P less than .01). Adding indomethacin did not affect inhibition of growth. CONCLUSION: Interleukin-1 beta inhibits growth of normal human endometrial stromal cells in vitro and does not appear to be mediated by arachidonic acid metabolites. This inhibition of growth may be important for maintenance of a normal endometrial phenotype.

Cell Division↗
PubMedDate not supplied

Ileo-rectal fistula complicating advanced ovarian carcinoma.

Fistula between the bowels and an ovarian carcinoma is recognized but rare complication. Internal malignant fistula of the gastrointestinal tract involving two or more loops of different segments of the bowel and genitourinary structure are rare. The colon is frequently one of the participating loops. In reviewing the literature, however, we were unable to find a previous report of ileo-rectal fistula as a complication of an ovarian carcinoma. A case report and review of the English medical literature are presented with emphasis on the cause, clinical presentation, and management of advanced ovarian cancer with ileo-rectal involvement.

Carcinoma↗