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H S Ryu

Publications and source records attributed to H S Ryu.

At least 19 recordsLinked to original sources
PubMed2006

Prognostic factors and expression of p53 and mdm-2 in uterine sarcomas.

OBJECTIVES: To evaluate the clinicopathologic prognostic factors of uterine sarcoma, and determine whether overexpression of p53 and mdm-2 proteins correlate with overall survival and prognostic factors. METHODS: Thirty specimens from 43 patients with uterine sarcoma were available for slide review and evaluated by immunohistochemistry at Yonsei and Ajou University Medical Centers for the expression of p53 and mdm-2. RESULTS: Overall survival was found to correlate to histologic type of uterine sarcoma, surgical stage, tumor grade, and mitotic index. Whereas 63% of the sarcomas expressed p53, with a significant correlation to overall survival, 60% expressed mdm-2, with a significant correlation to the mitotic index but not to overall survival. CONCLUSION: Histologic type, surgical stage, tumor grade, mitotic index, and p53 expression were prognostic factors of the overall survival of patients with uterine sarcoma.

Adult↗
PubMed2006

Progesterone-dependent release of transforming growth factor-beta1 from epithelial cells enhances the endometrial decidualization by turning on the Smad signalling in stromal cells.

Endometrial decidualization results from the differentiation of stromal cells in an ovarian steroid-sensitive manner. Human endometrial tissues obtained from fertile women at various stages of the menstrual cycle were subjected to immunohistochemistry to localize the components of the transforming growth factor-beta (TGF-beta) system. TGF-beta receptor-I and -II expression was higher in stromal cells than in epithelial cells during the secretory phase while no such variation was observed during the proliferative phase. The expression of phosphorylated Smad3 (pSmad2/3), an activated form of a component of the TGF-beta signalling pathway, and translocation of pSmad2/3 from the cytoplasm to the nucleus were more pronounced in secretory endometrium. In coculture of human endometrial epithelial with stromal cells, each isolated from the proliferative endometrium, administration of progesterone stimulated decidualization as well as TGF-beta signalling activation in stromal cells. Progesterone also significantly elevated the concentration of TGF-beta1 in the coculture medium. Careful manipulation of the coculture, i.e. selective addition and omission of the cellular components, showed that this progesterone-induced increase in secretion of TGF-beta1 come mainly from epithelial cells. Moreover, administration of TGF-beta1 (10 ng/ml) directly to cultured stromal cells enhanced the expression of prolactin as well as pSamd2/3 even without progesterone. Taken together, our present data support the notion that progesterone induces stromal decidualization indirectly, i.e. by enhancing the expression and secretion of TGF-beta1 from epithelial cells. The secreted, epithelial-derived TGF-beta1 then acts on adjacent stromal cells, at least in part, to turn on Smad signalling that could lead to stromal decidualization.

Adenomyoma↗
PubMed2006

Sonographic findings of placental lacunae and the prediction of adherent placenta in women with placenta previa totalis and prior Cesarean section.

OBJECTIVE: To investigate the value of transvaginal sonographic findings of intraplacental lacunae for predicting adherent placenta and clinical outcome in patients with placenta previa totalis and a history of Cesarean section. METHODS: Fifty-one patients with placenta previa totalis diagnosed by transvaginal sonography and with a history of Cesarean section who delivered at our hospital were included in the study. The sonographic findings of intraplacental lacunae were classified into one of four grades. Pathological analysis of the placenta was performed for all patients who delivered, and in cases of hysterectomy, examination of the uterus was also performed. The placental findings and obstetric complications, including massive transfusion, intensive care unit admission and Cesarean hysterectomy, were compared with the grade of lacuna. RESULTS: Lacunae were classified as Grade 1+ in 10 cases, Grade 2+ in 11 cases, Grade 3+ in five cases and as Grade 0 (i.e. lacunae were absent) in the remaining 25 cases. When lacunae of > or = Grade 1+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing adherent placenta were 86.9%, 78.6%, 76.9% and 88.0%, respectively. When lacunae of > or = Grade 2+ were considered, the sensitivity, specificity, positive predictive value and negative predictive value of diagnosing placenta increta or percreta were 100%, 97.2%, 93.8% and 100%, respectively. Hysterectomy was performed in 18 cases, among whom two cases showed Grade 1+ lacunae, 11 cases showed Grade 2+ lacunae, and five cases showed Grade 3+ lacunae. No hysterectomy was performed in any case in which lacunae were absent. Compared to those without lacunae, the number of massive transfusions and intensive care unit admissions and cases of disseminated intravascular coagulopathy and Cesarean hysterectomy were significantly greater in those with lacunae (P < 0.0001). CONCLUSION: Transvaginal sonographic findings of intraplacental lacunae in patients with placenta previa totalis and a history of Cesarean section are useful in the prediction of adherent placenta and may have a role in the prediction of clinical outcome.

Adult↗
PubMed2005

New cold-adapted lipase from Photobacterium lipolyticum sp. nov. that is closely related to filamentous fungal lipases.

A Photobacterium strain, M37, showing lipolytic activity, was previously isolated from an intertidal flat of the Yellow Sea in Korea and identified as Photobacterium lipolyticum sp. nov. In the present study, the corresponding gene was cloned using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (1,023 bp) corresponded to a protein of 340 amino acid residues with a molecular weight of 38,026. No sequence similarity was found with any known bacterial lipases/esterases; instead, the most similar enzymes were several filamentous fungal lipases. Although the similarity was very low (less than 16%), there were many conserved regions over the entire sequence and N-terminal oxyanion hole (RG) region, a signature sequence of filamentous fungal lipases. The novel protein M37 was produced in both a soluble and insoluble form when the Escherichia coli cells harboring the gene were cultured at 18 degrees C. The soluble protein exhibited lipase activity in a pH-stat assay using an olive oil emulsion. The M37 lipase also displayed a maximum activity at 25 degrees C and maintained its activity at a low temperature range (5-25 degrees C) with an activation energy (E(a)) of 2.07 kcal/mol. Accordingly, these results indicate that the M37 lipase from P. lipolyticum sp. nov. is a new cold-adapted enzyme.

Amino Acid Sequence↗
PubMed2002

Clinical outcomes of pregnancy with one elevated glucose tolerance test value.

OBJECTIVE: To evaluate clinical outcomes of pregnancies with one elevated glucose tolerance test. METHODS: We performed a 50 g glucose challenge test (GCT) in 5,019 pregnant women at 24-28 weeks of gestation. In 1,170 women with plasma glucose levels over 130 mg/dl, a 100 g oral glucose tolerance test (OGTT) was performed at 28-32 weeks of gestation. During follow-up, 282 patients were lost and in the 888 cases that were followed-up, 189 were excluded because of GDM. Therefore 699 study patients were divided into four groups: No Elevated group (NE, N = 577) with all four normal 100 g OGTT values, and Groups 1 (N = 16), 2 (N = 35), and 3 (N = 71) with one elevated 100 g OGTT value after 1, 2 and 3 h, respectively. RESULTS: Poor maternal outcomes (NE group, Group 1, Group 2, Group 3: 17.5%, 37.6%, 22.9%, 25.3%) with pre-eclampsia, cesarean delivery for cephalopelvic disproportion, failure to progress, or fetal distress, was highest in Group 1 (odds ratio 2.94; 95% confidence interval 1.02-8.42). Poor perinatal outcomes (15.8%, 43.1%, 14.3%, 21.1%) with any one of the following; fetal distress, Apgar score of < 7 at 5 min, hypoglycemia, respiratory distress syndrome, small for gestational age and perinatal death, was also highest in Group 1 (odds ratio 4.24; 95% confidence interval 1.02-17.52). CONCLUSION: Pregnancies with one elevated glucose tolerance test value after 1 h exhibited increased adverse maternal and perinatal outcomes compared with the group with all normal OGTT values or the groups with an elevated glucose tolerance test value after 2 or 3 h.

Adult↗
PubMed2001

Localization of matrix metalloproteinases on endometrial cancer cell invasion in vitro.

OBJECTIVES: In this study, we have established an in vitro three-dimensional (3D) coculture, where normal endometrial stromal cells and endometrial cancer cells were cocultured under defined hormonal conditions, to investigate the potential paracrine effects on synthesis and secretion of matrix metalloproteinases (MMPs) and, thus, cancer invasion. METHODS: Endometrial stromal cells were obtained by biopsy, cultured in the presence of 100 nM estrogen for 3 days, and then mixed with extracellular matrix (ECM) composed of collagen I and matrigel in a 4:1 ratio. After 3 more days in culture, a 3D coculture was established with HEC-1A cells, an endometrial adenocarcinoma cell line, grown on top of the mixture under various ovarian steroids (no steroid, 100 nM beta-estradiol (E2), or 1.0 microM progesterone (P4)) for 10 days. The expression and localization of MMP-2, MMP-9, and integrin beta 3 subunit were visualized by immunocytochemistry and analyzed by reverse transcription polymerase chain reaction (RT-PCR). The extent of cancer invasion was quantified by Boyden's chamber assay. RESULTS: Integrin beta 3 subunit was localized along the cell surface of HEC-1A cell under all three hormonal conditions. MMP-2 was located in the cytoplasm of stromal cells and on the surface of HEC-1A cells. Synthesis and secretion of stromal MMP-2 were increased in the presence of ovarian steroids. In contrast, expression of stromal MMP-9 was suppressed in the presence of ovarian steroids. No MMPs were synthesized in HEC-1A cells. Invasion assay revealed that HEC-1A cells achieved high tumoral invasiveness in the presence of beta-estradiol. CONCLUSIONS: These findings suggest that stromal cell-derived MMP-2 is translocated to the surface of HEC-1A cells. Integrin beta 3 subunit might contribute, in part, to providing a binding site for MMP-2. Thus, HEC-1A cells invade by recruiting MMP-2 secreted by stromal cells, which is greatly enhanced in the presence of beta-estradiol. The 3D coculture provides an excellent experimental system in which single parameters can be isolated from a complex in vivo system in the process of endometrial cancer invasion.

Adenocarcinoma↗
PubMed2001

Prevalence of endoscopic reflux esophagitis among Koreans.

BACKGROUND AND AIM: Although reflux esophagitis is believed to be common in the Western population, very few epidemiologic data on reflux esophagitis in Koreans are available. The aims of this study were to evaluate the prevalence of endoscopic reflux esophagitis in patients who came for a physical check-up at Korea University Hospital, and to study the relationship between various factors relevant to reflux disease. METHODS: This study was carried out prospectively on 7,015 patients who received an esophagogastroduodenoscopy from September 1996 to December 1997. Most of the patients were free of symptoms and had come for their self-paid check-up. RESULTS: The overall prevalence of reflux esophagitis was 3.4%, and most of the patients had a mild degree of esophagitis representing grade 1 in 98.3% and grade 2 in 1.7%. The male: female ratio for esophagitis was 7 : 1, and the body mass index (BMI) was significantly higher in patients with reflux esophagitis. A hiatal hernia was found in 166 patients with esophagitis (68.6%), but only in 9.2% patients without esophagitis (P < 0.05). Smoking and alcohol consumption were associated with the development of reflux esophagitis (P < 0.05). CONCLUSIONS: The prevalence of endoscopic reflux esophagitis among Koreans is 3.4%, and most of the patients had a mild grade esophagitis. Smoking, alcohol consumption, the presence of a hiatal hernia and a higher BMI are associated with the development of reflux esophagitis.

Esophagitis, Peptic↗
PubMed2001

Endoscopic removal of sharp foreign bodies impacted in the esophagus.

BACKGROUND AND STUDY AIMS: Impacted sharp foreign bodies in the esophagus can be very difficult to manage. When attempts are made to remove such objects inappropriately, life-threatening complications such as perforation can occur. The aim of this study was to evaluate the safety and efficacy of endoscopic removal of impacted sharp foreign bodies in the esophagus using proximal dilatation with an oral side balloon or transparent cap. PATIENTS AND METHODS: A total of 22 patients (10 men, 12 women) with impacted sharp foreign bodies in the esophagus underwent endoscopic extraction. The following technique was successfully performed at our hospital. An oral side balloon (Top Co., Japan) for esophageal variceal sclerotherapy was attached to the distal part of the endoscope. With the patient under local anesthesia, the endoscope was inserted as far as the proximal part of the esophageal foreign body. The oral side balloon was then gradually inflated. Dilatation of the proximal part of the esophagus made it possible to release the impacted sharp foreign body from the esophageal wall. A transparent cap was used for foreign bodies in the upper esophagus when there were difficulties with the oral side balloon. RESULTS: The types of foreign body removed were fish bones (n = 9), press-through packages (n = 8), chicken bones (n =3), dentures (n = 1), and a wrist watch (n = 1). Endoscopic removal was successful in all but one of the cases, in which a fish bone had to be extracted surgically. CONCLUSIONS: The proximal dilatation method using an oral side balloon or transparent cap is safe and effective in removing sharp foreign bodies from the esophagus, avoiding surgery and possible perforation.

Adult↗
PubMed2001

Inconsistent association of esophageal symptoms, psychometric abnormalities and dysmotility.

OBJECTIVES: The aim of this study was to characterize the psychometric profiles of symptomatic patients with abnormal esophageal motility and symptomatic patients with normal manometric findings compared to asymptomatic controls. METHODS: A total of 113 patients with abnormal esophageal motility (7 achalasia, 8 diffuse esophageal spasm, 27 nutcracker esophagus, 37 hypertensive lower esophageal sphincter, 21 hypotensive peristalsis, 13 failed peristalsis), 23 symptomatic controls with similar esophageal symptoms but normal manometry, and 27 asymptomatic controls were enrolled. Validated questionnaires assessing depression (Beck Depression Inventory), anxiety (Spielberger State Anxiety Inventory or Trait Anxiety Inventory), and somatization (Psychosomatic Symptom Checklist) were administered to all subjects. RESULTS: Patients with both esophageal symptoms and either hypertensive lower esophageal sphincter, nutcracker esophagus, or hypotensive contractions exhibited increased somatization, acute anxiety, or depression compared to asymptomatic controls but not compared to symptomatic controls. On the other hand, the psychometric profiles of patients with achalasia and diffuse esophageal spasm were strikingly normal. Among esophageal symptoms, chest pain was closely correlated with psychometric abnormalities. CONCLUSIONS: The esophageal symptoms of patients with abnormal esophageal motility may relate to the underlying psychological abnormalities, independent of manometric abnormalities.

Analysis of Variance↗
PubMed2001

Differentiation between reinfection and recrudescence of helicobacter pylori strains using PCR-based restriction fragment length polymorphism analysis.

The aim of this study was to evaluate whether PCR-based restriction fragment length polymorphism (RFLP) analysis was effective in differentiating between reinfection and recrudescence of H. pylori strains. Following a 1-2 week regimen of omeprazole 20 mg, amoxicillin 1.0 g, and clarithromycin 500 mg twice daily, twenty patients with duodenal ulcer were enrolled in the study. Ten patients (group 1, control) were not successfully treated, and another 10 patients (group 2) exhibited recurrence of infection 6-24 months following the therapy. Follow-up diagnosis was performed by Giemsa stain and CLO test. RFLP profiles of antral and midbody biopsy specimens were compared before and after therapy. PCR products using the ureC gene were digested with restriction enzymes Hha I, Mbo I, and Hind III, and the fragments generated were analyzed by agarose gel electrophoresis. Hha I, Mbo I, and Hind III digestion produced 13, 7, and 2 distinguishable digestion patterns, respectively. There was no difference in RFLP profiles seen before and after the therapy in 17 duodenal ulcer patients, while different RFLP profiles were discovered in 3 patients. Following treatment, one (group 2) patient differed in Mbo I, and two (one each from both groups) patients differed in Hha I and Mbo I RFLP patterns. Eight of group 2 patients showed recrudescence of previous infection and two patients had reinfection by another strain. This study supports the hypothesis that PCR-based RFLP analysis can be effective for differentiating reinfection and recrudescence of H. pylori strains following triple therapy.

Adult↗
PubMed2001

The value of cystoscopy and intravenous urography after magnetic resonance imaging or computed tomography in the staging of cervical carcinoma.

The clinical staging system for cervical carcinoma presently recommended by the International Federation of Gynecology and Obstetrics (FIGO) does not include MRI or CT findings and thus suffers limited accuracy. Recently however, the positive contributions of MRI and CT to preoperative staging have been reported. This study involves a determination of the value of routine cystoscopy and intravenous urography, in the detection of bladder invasion or hydronephrosis resulting from cervical carcinoma, among patients who had undergone MRI or CT. Among a total 296 patients with cervical carcinoma, 271 patients (92%) had undergone MRI and 25 (8%) CT. Bladder invasion was identified pathologically by cystoscopic biopsy in 8 (57%) of the 14 patients with suspected bladder invasion on MRI or CT. There was no bladder invasion in any of the other cases lacking in bladder invasion evidence on MRI or CT. Hydronephrosis was identified by intravenous urography in 18 patients, as it also was in all of these cases on MRI or CT, confirming a negative predictive value for MRI or CT, in detecting bladder invasion or hydronephrosis from cervical carcinoma, of 100%. Therefore, although MRI or CT cannot totally replace cystoscopy, the latter is unnecessary in the absence of bladder invasion evidence on MRI or CT. Intravenous urography, however, can be safely omitted whenever MRI or CT is performed.

Adult↗
PubMed2001

A case of primary adenosquamous carcinoma of the liver presented with liver abscess.

Primary adenosquamous carcinoma of the liver is a very rare type of cholangiocarcinoma and is defined as a cancer containing both squamous and adenomatous components in the same lesion. Recently, we experienced a primary adenosquamous carcinoma of the liver presented as liver abscess. A 63-year-old man was presented with a 4-day history of fever and chill. The radiologic study showed a 4 cm-sized, central hypoattenuated mass with peripheral rim enhancement in the left lobe of the liver. Ultrasonography-guided aspiration and biopsy suggested an adenocarcinoma with abscess in the liver. At laparotomy, the tumor occupied the left lobe of the liver and invaded the right diaphragm. An extended left lobectomy and a partial excision of the involved diaphragm were done. Grossly, the tumor was 6 x 5 x 5 cm in size and had an eccentric necrosis. Microscopically, the tumor was composed of adenocarcinoma and squamous cell carcinoma with a transitional area.

Carcinoma, Adenosquamous↗
PubMed2000

High cyclooxygenase-2 expression in stage IB cervical cancer with lymph node metastasis or parametrial invasion.

OBJECTIVE: The enzymes cyclooxygenase (COX)-1 and -2 are necessary for the synthesis of prostaglandins. COX-2 is usually absent in normal cells and is upregulated and expressed as a product of the "immediate early" gene during inflammatory processes. In previous studies, the expression of COX-2 has been shown to be induced by proinflammatory cytokines, and suggestions have been made that overexpression of COX-2 suppresses apoptosis and is directly related to tumor growth. We have attempted to determine a relationship between tumor invasion and metastasis of uterine cervical cancer and COX and apoptosis by comparing the protein expression of apoptosis, COX-1, and COX-2 in tumor tissues. METHODS: The subjects were 36 patients who were FIGO stage IB uterine cervical cancer patients who underwent surgery at Ajou University Hospital. There were 12 cases with lymph node or parametrial involvement. All tissues were subjected to immunohistochemical staining for COX-1, -2, and TUNEL method for apoptosis detection, and the following results were obtained. RESULTS: Tumor tissues confirmed by cytokeratin were separated into tumor surface, tumor stroma, and invasion site portions, in which decreased apoptosis was observed in the invasion sites. COX-2 expression was observed in all tumor tissues and was especially strong in the tumor invasion site. Therefore, it is suggested that COX-2 expression may suppress cell apoptosis at the tumor invasion site. When COX-2 expression was investigated according to the groups with regard to the presence of lymph node or parametrial involvement, there was a statistically significant (Mann-Whitney U test) COX-2 expression difference in the tumor invasion site (P value = 0.040) and the tumor stroma (P value = 0. 028). CONCLUSIONS: In surgically treated stage IB cervical cancer patients, COX-2 was significantly expressed when lymph node or parametrial involvement was present. These results suggest that the expression of COX-2 in stage IB cervical cancer may downregulate apoptotic processes and thus enhance tumor invasion and metastasis.

Apoptosis↗
PubMed2000

Osteoconduction at porous hydroxyapatite with various pore configurations.

To assess the histological response and the reinforcing effects of bone ingrowth within porous hydroxyapatite (HA) implants depending on pore geometry, four kinds of cylindrical-type with parallel linear pores phi50, 100, 300, 500 microm), one kind of sponge-type with irregular interconnecting pores (phi250 microm) and one cross-type with crossing linear pores (phi100 x 120 microm) of porous HA were prepared. Eighty-four rabbits were divided into six groups, and a 5 x 5 x 7 mm sized porous HA block was inserted through the medial cortical window of the proximal tibia. Histomorphological changes were examined using light and scanning electron microscopy. A biomechanical compression test was performed using material test machines. After implantation, the implants showed different histological changes depending on pore geometry. Active osteoconduction was also found in the phi50 microm sized cylindrical-type porous HA. Evidence of remodeling of new bone and bone marrow formation within porous HA was found in the larger cylindrical-types (phi300, 500 microm), and the sponge- and cross-types. The biomechanical test showed that the ultimate compressive strength increased significantly in the phi300 microm sized cylindrical-type, and in the sponge- and cross-types eight weeks after implantation. Porous HA with cylindrical pores could be a useful graft material due to its strength, osteoconductivity and the ease with which its pore geometry can be controlled.

Animals↗
PubMed2000

Evaluation of pancreatic exocrine function using pure pancreatic juice in noninsulin-dependent diabetes mellitus.

To investigate the pancreatic exocrine function in noninsulin-dependent diabetes mellitus (type 2 DM), we evaluated the pure pancreatic juice obtained by endoscopic cannulation of the main pancreatic duct in 13 healthy control subjects and 22 patients with type 2 DM who had no evidence of pancreatic disease. Samples of pancreatic juices were collected in six fractions for 30 minutes at 5-minute intervals after an intravenous bolus injection of secretin (0.25 CU/kg) and cholecystokinin-8 (CCK) (40 ng/kg). The responses of plasma glucose, insulin, and C-peptide to intravenous administration of glucose (50%, 40 mL) were measured. The levels of plasma insulin and C-peptide levels in type 2 DM were the same as in healthy controls in the basal state but did not further increase in response to an intravenous glucose. This suggested that patients with type 2 DM had insulin secretion defect rather than insulin deficiency. Pancreatic secretions including volume, bicarbonate, and protein output in response to stimulation with secretin, and CCK were significantly reduced when compared to the healthy controls. We conclude that patients with type 2 DM exhibit impairment of pancreatic exocrine secretion and that this impairment might not be related to insulin deficiency. Therefore, we recommended that careful evaluation for exocrine pancreatic function in type 2 diabetics who have any clinically suspicious symptoms of pancreatic insufficiency.

Adult↗
PubMed1999

Association of pseudoachalasia with advancing cancer of the gastric cardia.

BACKGROUND: Pseudoachalasia is attributable to malignant tumors of the gastric cardia in more than 50% of cases. Study of the progression of esophageal manometric abnormalities with increasing tumorous involvement of the esophagogastric junction may improve our understanding of the pathophysiologic characteristics of pseudoachalasia. METHODS: During a 2-year period, esophageal manometric characteristics were evaluated for 17 of 21 consecutive patients with cancer of the gastric cardia. Manometry was not possible in the other four. Manometric parameters assessed included lower esophageal sphincter pressure, percentage lower esophageal sphincter relaxation, and percentage failed peristalsis. The extent of malignant involvement of the esophagogastric junction was graded as none, less than 50% of the circumference, or 50% or more of the circumference, assessed from surgical specimens in 13 cases and endoscopy in 4 cases. RESULTS: Pseudoachalasia was diagnosed in 3 cases, all with 50% or greater circumferential involvement of the esophagogastric junction. The first manometric indication of evolving pseudoachalasia was impaired lower esophageal sphincter relaxation; loss of peristaltic function was a secondary consequence. CONCLUSIONS: These findings suggest that the primary mechanism of pseudoachalasia with gastric cardia cancer is malignant stenosis of the esophagogastric junction.

Adult↗