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J H Hyun

Publications and source records attributed to J H Hyun.

34 records · Page 2Linked to original sources
PubMed1999

Bilateral ovarian carcinoma metastatic from the ampulla of Vater: a rare Krukenberg tumor.

Carcinoma of the ampulla of Vater is a relatively rare neoplasm and its longterm survival rate is considerably high. However, because of differences in tumor pathologic features and local invasiveness, a 5-year survival rate differ widely. We present a case of metastatic carcinoma of the ampulla of Vater presenting as a Krukenberg tumor in a 59-year-old woman. Eight months earlier, she had been diagnosed as well-differentiated adenocarcinoma of the ampulla of Vater. Abdominal examination revealed a hard mass with mild tenderness in the RLQ area. The laboratory findings were unremarkable except for mild anemia. CT scan of the abdomen revealed enlargement of both ovaries. An exploratory laparotomy disclosed bilateral ovarian masses, 18 x 12 x 8 cm and 8 x 5.5 x 4 cm in size, respectively. Histologic findings of the both ovarian masses were consistent with metastatic adenocarcinoma from the ampulla of Vater.

Ampulla of Vater↗
PubMed1999

Endoscopic retrograde pancreatographic findings of pancreatic lipomatosis.

Pancreatic lipomatosis is characterized by fatty infiltration or replacement of the pancreas, and has been associated with many conditions. We recently experienced two cases of pancreatic lipomatosis in patients with pancreatic pseudocyst and a case of lipomatosis in diabetes mellitus. In these patients, abrupt obstruction of the main pancreatic duct with smooth tapering is a typical endoscopic retrograde pancreatography (ERP) finding of pancreatic lipomatosis and must be differentiated with pancreatic carcinoma.

Adult↗
PubMed1999

Epirubicin, cisplatin, oral UFT, and calcium folinate in advanced gastric carcinoma.

UFT (uracil and tegafur in a 4:1 molar ratio) plus calcium folinate treatment has favorable activity and tolerable toxicity in patients with advanced gastric carcinoma. High response rates have been reported in patients with advanced gastric carcinoma receiving a schedule of epirubicin, cisplatin (Platinol), and protracted infusion of 5-fluorouracil (5-FU). Replacing the inconvenient infusion pump and intravenous catheter needed for protracted infusion of 5-FU, we administered oral UFT plus calcium folinate (Orzel) to 37 patients (median age, 55 years; median World Health Organization [WHO] performance status of 1) with locally advanced or metastatic gastric carcinoma. Epirubicin 50 mg/m2 and cisplatin 60 mg/m2 were administered by intravenous injection on day 1; UFT 360 mg/m2/day po was administered in conjunction with oral calcium folinate 25 mg/m2/day in divided daily doses for 21 days, followed by a 7-day rest period. Courses were repeated every 4 weeks. Among 37 evaluable patients who received a median of four courses of treatment (range, 2 to 10), two achieved a complete response and 18 a partial response, for an overall response rate of 54% (95% confidence interval, 39% to 70%). Stable disease was reported in 12 patients (32.4%) and disease progression in another five (13.5%). The median duration of survival was 10 months (range, 2 to 15+). The main toxicities were nausea/vomiting, leukopenia, diarrhea, and oral mucositis. WHO grade 3 or 4 toxicity included leukopenia in 14 patients (37.8%), nausea/vomiting in 11 (29.7%), oral mucositis in five (13.5%), and diarrhea in four (10.8%). Epirubicin, cisplatin, and oral UFT plus calcium folinate, a convenient outpatient regimen, has significant activity and tolerable toxicities in patients with gastric carcinoma.

Adenocarcinoma↗
PubMed1998

Molecular cloning of cDNA for pro-phenol-oxidase-activating factor I, a serine protease is induced by lipopolysaccharide or 1,3-beta-glucan in coleopteran insect, Holotrichia diomphalia larvae.

Previously, we identified two pro-phenol oxidase-activating factors, named PPAF-I and PPAF-II, directly involved in the activation of the purified pro-phenol oxidase (pro-PO) from the hemolymph of the coleopteran, Holotrichia diomphalia larvae [Lee, S. Y., Kwon, T. H., Hyun, J. H., Choi, J. S., Kawabata, S. I., Iwanga, S, & Lee, B. L. (1998) Eur. J. Biochem. 254, 90-97]. Here, we report molecular cloning of cDNA for PPAF-I. Based on the sequence of the cloned cDNA, the PPAF-I gene appears to encode a member of serine protease zymogen consisting of 365 amino acid residues with a molecular mass of 40193 Da. The 109 amino acid residues preceding the amino-terminus Ile residue of the mature protein seem to constitute a prepro-sequence. The mature protein is a serine protease composed of 256 amino acids with a calculated molecular mass of 28009 Da. The overall structure is highly similar to that of Drosophila easter serine protease (42.9% identity), an essential serine protease zymogen for pattern formation in normal embryonic development. The locations of disulfide linkages in the pro-segment of PPAF-I were similar to those of Tachypleus proclotting enzyme and the mammalian neutrophil-derived defensin. Furthermore, [3H]diisopropylphosphate (iPr2P)-labeled PPAF-I was specifically produced from the crude preparation of PPAF-I zymogen by incubation with lipopolysaccharide or 1,3-beta-glucan, whereas [3H]iPr2P-labeled PPAF-I was not produced under the same conditions in the absence of these microbial polysaccharides. These results indicate that the pro-PO-activation system in H. diomphalia larvae may proceed with the activation of PPAF-I zymogen by microbial polysaccharides.

Amino Acid Sequence↗
PubMed1998

In vitro activation of pro-phenol-oxidase by two kinds of pro-phenol-oxidase-activating factors isolated from hemolymph of coleopteran, Holotrichia diomphalia larvae.

Previously, we purified and characterized a pro-phenol-oxidase (pro-PO) of 79 kDa from coleopteran insect, Holotrichia diomphalia larvae [Kwon et al. (1997) Mol. Cells 7, 90-97]. Here, we describe the identification of two pro-PO-activating factors (PPAF), named PPAF-I and PPAF-II, directly involved in the activation of the isolated pro-PO. When pro-PO was incubated with either PPAF-I or PPAF-II, no phenol oxidase activity was observed. However, incubation of pro-PO with both PPAF-I and PPAF-II specifically exhibited phenol oxidase activity. The purified PPAF-I with a molecular mass of 33 kDa on SDS/PAGE had characteristics of a serine protease. It exhibited amidase activity against fluorogenic peptide substrates, tert-butoxycarbonyl-phenylalanyl-seryl-arginyl-4-methylcoumaryl-7-amide being the best among the substrates examined. The activity was completely inhibited by 0.02 mM p-nitrophenyl-p'-guanidinobenzoate HCl and diisopropylflurophosphate. The NH2-terminal sequence of PPAF-I had significant sequence similarity to those of serine proteases. On the other hand, the purified PPAF-II had a molecular mass of 40 kDa on SDS/PAGE and 400 kDa determined by gel filtration, indicating an oligomeric protein. The NH2-terminal sequence of PPAF-II showed no similarity to known proteins. PPAF-II exhibited no amidase activity against the fluorogenic substrates. Reconstitution experiments and immunoblotting analysis using affinity-purified antibody against pro-PO demonstrated that PPAF-I first cleaves the intact pro-PO to an intermediate of 76 kDa with no phenol oxidase activity, and then, PPAF-I converts the intermediate to the active phenol oxidase of 60 kDa in the presence of PPAF-II. These results indicate that the activation of pro-PO system in hemolymph of H. diomphalia larvae is accomplished by at least two activating factors, a serine protease and a protein cofactor.

Amidohydrolases↗
PubMed1998

Effects of levosulpiride in patients with functional dyspepsia accompanied by delayed gastric emptying.

OBJECTIVES: Levosulpiride is the levo-enantiomer of sulpiride, a well-known antiemetic, antidyspeptic and antipsychotic drug. This study was undertaken to investigate the effects of levosulpiride on dyspeptic symptoms and gastric motor function in a group of patients with functional dyspepsia showing delayed gastric emptying. METHOD: Forty two eligible patients were entered into a 3 week, double-blind randomized comparison of 25mg of levosulpiride or placebo t.i.d.. Symptom assessment and gastric scintigraphy following the intake of scrambled egg sandwich, were performed in each patient before and after treatment. RESULTS: The improvement of symptom score in levosulpiride group was higher than the placebo group (p < 0.05). We assessed global efficacy, which was excellent in 1 (6%), good 11 (65%), fair 4 (24%), nil 1 (6%) of those receiving levosulpiride, and fair 9 (60%), nil 5 (33%), poor 1 (6%) of those receiving placebo. Levosulpiride tended to be more effective than placebo in relieving the dyspeptic symptoms especially in the subgroups of dysmotility-like (p < 0.05) and nonspecific (p < 0.05) as compared to other subgroups (p = 0.16). The reduction of gastric emptying time after levosulpiride treatment was more marked than Placebo group (p < 0.05). We found a significant correlation between changes of symptom score and gastric emptying time (r = 0.47, p = 0.01). No serious adverse effects were reported after administration of either levosulpiride or placebo. Only two patients reported mild somnolence during levosulpiride administration. CONCLUSIONS: Levosulpiride is effective and well tolerated in patients with functional dyspepsia accompanied by delayed gastric emptying. Its efficacy may be related to its action on the gastric motor function by improving the delayed gastric emptying.

Adolescent↗
PubMed1997

Endoscopic resection of submucosal tumor of the esophagus: results in 62 patients.

BACKGROUND AND STUDY AIMS: Although most submucosal tumors of the esophagus are benign, reliable exclusion of leiomyosarcoma requires histological analysis. However, this is rarely possible with an endoscopic forceps biopsy. In an attempt to establish the diagnosis, and as an alternative to surgery, we present here our experience with the endoscopic removal of submucosal tumors of the esophagus using two different techniques. PATIENTS AND METHODS: Sixty-two patients (38 men, 24 women, mean age 47) with submucosal tumors of the esophagus were treated endoscopically. If the tumor was less than 2 cm in diameter, polypoid, or showed a round protrusion with at least moderate elevation at endoscopy, a conventional snare polypectomy was performed. If the tumor was larger than 2 cm in diameter or only mildly elevated, the technique of modified endoscopic incisional enucleation was carried out, consisting of complete stripping of the overlying tissue followed by tumor enucleation using an electrocautery snare and a coagulation electrode. RESULTS: Based on these criteria, 36 patients underwent conventional snare polypectomy, and 25 received endoscopic incisional enucleation; complete resection of the tumor was possible in these 61 cases. In one patient, only partial removal was possible, due to firm and wide adhesions to the surrounding tissue. The tumor diameters ranged from 0.6 cm to 7.5 cm, with a mean value of 1.9 cm; 14 tumors measured more than 3 cm. At histopathology, the resected specimens were found to be 56 leiomyomas, four granular cell tumors, one neurogenic tumor, and one cyst. No serious complications such as perforation or massive bleeding occurred, and oozing bleeding, which was encountered in three patients, was easily managed by endoscopic electrocoagulation. During the follow-up period (mean 38.4 months, range 3-107 months) no recurrence was observed in any of the 61 patients who received complete resections. CONCLUSION: This method of endoscopic removal of submucosal tumors of the esophagus appears to be safe and effective in experienced hands. It allows complete histopathological workup, and at the same time complete removal of the tumor. The method can be considered as an alternative to surgery in symptomatic cases.

Adult↗
PubMed1997

Double-blind placebo-controlled study of cisapride in patients with nonspecific esophageal motility disorder accompanied by delayed esophageal transit.

BACKGROUND: Nonspecific esophageal motility disorder (NEMD) represents a difficult therapeutic challenge because of the heterogeneous nature of the esophageal motor functions. We studied the effects of cisapride on the esophageal symptoms and esophageal motor function in a group of patients with NEMD showing delayed esophageal transit. METHODS: Seventy eligible patients were entered into a 4-week, double-blind randomized comparison of 10 mg of cisapride or placebo, four times daily. Symptom assessment, esophageal manometry after wet swallows, and esophageal scintigraphy after intake of a liquid and solid bolus were performed in each patient before and after treatment. RESULTS: After 4 weeks of treatment cisapride significantly increased the prevalence of esophageal peristaltic contractions (percentage of total contractions, P < 0.05 versus base line and placebo) and significantly improved esophageal emptying of the solid bolus (P < 0.05 versus placebo) but not of the liquid bolus. Placebo did not have any significant effects versus base line on these variables. Both placebo and cisapride improved the distal esophageal amplitude versus base line (no significant intergroup differences). Symptom scores were significantly reduced after 4 weeks of treatment versus base line in both groups (no significant intergroup differences except for heartburn and regurgitation, P < 0.05). On global evaluation of treatment, significantly more patients in the cisapride group were rated as markedly or moderately improved, when compared with placebo. CONCLUSIONS: The results of the present study showed that cisapride is effective and well tolerated in patients with NEMD accompanied by delayed esophageal transit. Symptomatic improvement may possibly be related to its beneficial action on the esophageal body by increasing the number of peristaltic contractions and esophageal emptying of solids.

Adult↗
PubMed1996

Pseudoaneurysm and splenic infarction in chronic pancreatitis--a case report.

Peripancreatic pseudoaneurysm and splenic infarction are rare but life-threatening complications of chronic pancreatitis. The incidence of pseudoaneurysm in patients who undergo angiography for pancreatitis is about 10%. Clinically, pseudoaneurysm is hard to discover until rupture occurs. The authors have recently experienced a case of intact pseudoaneurysm and splenic infarction in chronic alcoholic pancreatitis. A bolus enhanced CT scan and angiography were essential to confirm these complications of pancreatitis. We managed these complications successfully by distal pancreatectomy and splenectomy.

Adult↗
PubMed1995

A new method of endoscopic variceal ligation-injection sclerotherapy (EVLIS) for gastric varices.

OBJECTIVES: For esophageal varices, endoscopic variceal sclerotherapy and band ligation have been effectively and frequently used, but these methods were not effective for gastric varices. In gastric varices, because of rich networks of feeding vessels and shunts that may exist in many cases, an effective therapeutic level of sclerosant is difficult to be maintained. Accordingly, we propose a new method called "Endoscopic Variceal Ligation-Injection Sclerotherapy (abbreviated EVLIS)" for gastiric varices, with focus on maintenance of the effective therapeutic level of a sclerosant by partially blocking the blood flow of gastric varices using the band ligation method. The study was undertaken prospectively to evaluate the efficacy and safety of EVLIS for the treatment of gastric varices. METHODS: EVLIS was performed in a group of 32 patients with gastric varices. Active bleeding varices were 11 and non-bleeding 21. Five cases were grade A, 12 grade B, and 14 grade C of Child's classification. Nine cases were type 1, 22 type 2, and 1 was type 3 of Hosking-Johnson's classification. RESULTS: The results of EVLIS were excellent, active bleeding of gastric varices in the 11 cases were successfully controlled and all the gastric varices of 32 cases including those bleeding varices were completely eradicated. The bleeding status, the Child's grade and the Hosking-Johnson's class do not appear to correlate in any way with the efficacy of this technique. No perforation or re-bleeding was observed in any of the patients until the mean 10.6 months of the follow-up period. CONCLUSIONS: EVLIS should be considered as an effective and safe treatment for gastric varices.

Adult↗
PubMed1994

Esophageal duplication cyst complicated with intramural hematoma--case report.

Esophageal duplication cysts account for a very small percentage of benign esophageal tumors and are infrequently symptomatic. Esophageal duplication cysts result from aberrant alignment of the normal vacuolization process that produce the esophageal lumen in the 5th to 8th week of embryonic life. Complications most often are bleeding into or infection of cysts. Recently, we experienced a case of esophageal duplication cyst complicated with intramural huge hematoma and the cause of hematoma could not be identified. We report it with a review of literatures.

Esophageal Cyst↗
PubMed1993

[Self-efficacy predictiveness and its determinants among preschoolers].

Precision of self-efficacy predictions on a ball-throwing task was compared between the younger group (3-year-olds; N = 40) and the older group (5-year-olds; N = 40). Three factors underlying the development of accurate efficacy expectations were examined. They were the effect of experience, the complexity of the task, and information of task performance. Results indicated that the predictions of the older group were more accurate than those of the younger group, and their predictions were significantly related to subsequent performance. They did more realistic efficacy predictions by using information of task performance and experience. The younger group showed no accuracy of self-efficacy predictions. But the presentation of information about task performance enabled them to make realistic efficacy predictions.

Child, Preschool↗
PubMed1991

Correlation of esophageal lengths with measurable external parameters.

Previous data for esophageal lengths are based on age related groups or cadaveric examination, both of which are improper for application to various individualized procedures. Because of the variability in height for any given age and longer length in vivo, individualized approximation is needed. Thus, we measured various anatomical levels of the esophagus using a flexible endoscope and correlated these data with measurable external body intervals. The mean esophageal length was 40.92 +/- 2.79, which is longer than the length derived from cadaveric examinations. Also, esophageal lengths which correlated better with height than any other body intervals, could be calculated from the following equation. Esophageal length from the upper incisors to the esophagogastric junction (L) can be expressed: L = 0.242 x height (Ht) + 2.078 cm (P = 0.000, R2 = 0525). The data from our study indicate that esophageal length can be reliably predicted using external body parameters before employing various procedures.

Adolescent↗
PubMed1991

A case of primary T-cell lymphoma of the duodenum.

Primary malignant lymphoma located in the duodenum is a rarity. A case of primary lymphoma of the duodenum in a 27-year-old man, in which the 2 discrete masses of duodenal bulb and the second portion with pancreatic head invasion was found, is reported here. Immunohistochemical evaluation of the present case showed that lymphoma cells expressed the T-cell markers MT1 and UCHL1. Treatment consisted of pancreaticoduodenectomy followed by antineoplastic chemotherapy.

Adult↗
PubMedDate not supplied

New approach to radial expansive force measurement of self expandable esophageal metal stents.

The accurate measurement of radial expansive force is crucial for optimal design and implantation of self expandable esophageal metal stents. In the present study, a new method of measurement under experimental conditions simulating actual stent implantation has been developed. This method offers precise and reproducible measurements and can be applied to a wide variety of stent types. In particular, the method enables one to measure expansive pressure as well as the true radial expansive force up to the radial compression ratio of 72%, covering the range of compression often encountered in a partially obstructed lumen. The test results for various kinds of metal stents are presented and compared. Based on these results, three important points of observation critical in explaining and predicting the expansion characteristics of stents have been reported. Further understanding and characterization of these findings will be necessary for developing new stents with outstanding clinical efficacy.

Compliance↗