Inhibitory effect of prostaglandin E(2) on the migration of nasal fibroblasts

BACKGROUND

Fibroblast migration is crucial for normal wound repair after sinonasal surgery. Prostaglandin E2 (PGE2) is a potent inhibitor of fibroblast functions including chemotaxis, proliferation, and matrix production. The purpose of this study was to determine whether PGE2 affects the migration of nasal fibroblasts and to investigate the mechanism of action of PGE2 on nasal fibroblasts.

METHODS

Primary cultures of nasal fibroblasts were established from inferior turbinate samples. Fibroblast migration was evaluated with scratch assays. Reverse-transcription polymerase chain reaction was performed for E prostanoid (EP) 1, EP2, EP3, and EP4 receptors. EP receptor-selective agonists and antagonists were used to evaluate receptor functions. Stimulatory G (Gs) proteins were activated to evaluate mechanisms. Intracellular cyclic adenosine monophosphate (cAMP) levels were measured by ELISA, and fibroblast cytoskeletal structures were visualized with immunocytochemistry.

RESULTS

PGE2 significantly reduced the migration of nasal fibroblasts. Agonists selective for the EP2 and EP4 receptors significantly reduced the nasal fibroblast migration. Antagonists of the EP2 and EP4 receptors inhibited the effect of PGE2 on nasal fibroblast migration. Activation of Gs protein and adenyl cyclase reduced nasal fibroblast migration.

CONCLUSION

PGE2 inhibited the migration of nasal fibroblasts via the EP2 and EP4 receptors, and this inhibition was mediated by cAMP elevation. Targeting specific EP receptors could offer therapeutic opportunities for conditions such as delayed wound healing after nasal surgery.

Effect of prostaglandin e2 on vascular endothelial growth factor production in nasal polyp fibroblasts

PURPOSE

Angiogenesis is involved in the pathogenesis of chronic rhinosinusitis with nasal polyps. We aimed to investigate the effects of prostaglandin E2 (PGE2) on vascular endothelial growth factor (VEGF) production, the role of E-prostanoid (EP) 4 receptors, and the signal transduction pathway mediating VEGF production in nasal polyp-derived fibroblasts (NPDFs).

METHODS

Eight primary NPDF cultures were established from nasal polyps, which were incubated with or without PGE2. Reverse transcription-polymerase chain reaction amplification of EP receptors (EP1, EP2, EP3, and EP4) and immunofluorescence staining for VEGF production were performed. VEGF production via the cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) and phosphatidylinositol 3-kinase (PI3K) pathways was evaluated by enzyme-linked immunosorbent assay.

RESULTS

All EP receptors were expressed in NPDFs. PGE2 significantly increased VEGF production concentration- and time dependently, and VEGF production was regulated by an EP4 receptor. Activation of intracellular cAMP regulated VEGF production. VEGF production was decreased by PKA and PI3K inhibitors via intracellular cAMP.

CONCLUSIONS

PGE2 stimulates VEGF production via the EP4 receptor in NPDFs. These results indicate that PGE2-induced VEGF production is mediated, at least partially, through cAMP-dependent signaling pathways. Therapies targeting the EP4 receptor may be effective in inhibiting the development of nasal polyps.

Effects of Histone Deacetylase Inhibitor on Extracellular Matrix Production in Human Nasal Polyp Organ Cultures

Background

Nasal polyposis is associated with a chronic inflammatory condition of the sinonasal mucosa and involves myofibroblast differentiation and extracellular matrix (ECM) accumulation. Epigenetic modulation by histone deacetylase (HDAC) inhibitors including trichostatin A (TSA) has been reported to have inhibitory effects on myofibroblast differentiation in lung and renal fibroblasts. The purpose of this study was to investigate the inhibitory effect of TSA on myofibroblast differentiation and ECM production in nasal polyp organ cultures.

Methods

Nasal polyp tissues from 18 patients were acquired during endoscopic sinus surgery. After organ culture, nasal polyps were stimulated with TGF-beta1 and then treated with TSA. Alpha-smooth muscle actin (α-SMA), fibronectin, and collagen type I expression levels were examined by reverse transcription–polymerase chain reaction (PCR), real-time PCR, Western blot, and immunofluorescent staining. HDAC2, HDAC4, and acetylated H4 expression levels were assayed by Western blot. Cytotoxicity was analyzed by the terminal deoxynucleotidyl transferase biotin–dUTP nick end labeling assay.

Results

The expression levels of α-SMA, fibronectin, and collagen type 1 were increased in nasal polyp after transforming growth factor (TGF) beta1 treatment. TSA-inhibited TGF-beta1 induced these gene and protein expression levels. Furthermore, TSA suppressed protein expression levels of HDAC2 and HDAC4. However, TSA induced hyperacetylation of histones H4. Treatment with TGF-beta1 with or without TSA did not have cytotoxic effect.

Conclusion

These findings provide novel insights into the epigenetic regulation in myofibroblast differentiation and ECM production of nasal polyp. TSA could be a candidate of a therapeutic agent for reversing the TGF-beta1–induced ECM synthesis that leads to nasal polyp development.

Increased expression of intelectin-1 in nasal polyps

BACKGROUND

Intelectin-1 is a new type of Ca(2+)-dependant soluble lectin in humans that has affinity for galactofuranose in carbohydrate chains of bacterial cell walls, indicating that intelectin-1 may play a role in immune defense against bacteria. The purpose of the current study was to determine the expression of intelectin-1 mRNA and protein and to localize intelectin-1 protein in nasal polyps and tissues from control subjects.

METHODS

Normal sphenoid sinus mucosa was obtained from 10 patients undergoing surgery for pituitary tumor. Nasal polyp samples were obtained from 10 patients undergoing endoscopic sinus surgery for chronic polypoid rhinosinusitis. Real-time polymerase chain reaction (PCR) was performed for intelectin-1 mRNA. Immunofluorescent staining was done for localization of intelectin-1 and quantitatively analyzed using computer-based image analysis. Western blot analysis was performed.

RESULTS

Real-time PCR and Western blot analysis showed that intelectin-1 expression in nasal polyps was increased compared with normal sinus mucosa. Using immunofluorescent staining, intelectin-1 was strongly stained in epithelium and submucosa of nasal polyps, and faint staining was found in normal sinus mucosa.

CONCLUSIONS

Intelectin-1 is expressed in human sinus mucosa and is increased in patients with nasal polyps. These results suggest a possible contribution for intelectin-1 in the pathophysiology of nasal polyps.

Inhibitory effect of ginsenoside Rg1 on extracellular matrix production via extracellular signal-regulated protein kinase/activator protein 1 pathway in nasal polyp-derived fibroblasts

Nasal polyps are associated with chronic inflammation of the sinonasal mucosa and are involved in myofibroblast differentiation and extracellular matrix (ECM) accumulation. Ginsenoside Rg1, a compound derived from Panax ginseng, shows antifibrotic and anticancer effects. However, the molecular effects of Rg1 on myofibroblast differentiation and ECM production remain unknown. The aims of this study were to investigate the effect of Rg1 on transforming growth factor (TGF)-β1-induced myofibroblast differentiation and ECM production and to determine the molecular mechanism of Rg1 in nasal polyp-derived fibroblasts (NPDFs). NPDFs were isolated from nasal polyps of seven patients who had chronic rhinosinusitis with nasal polyp. NPDFs were exposed to TGF-β1 with or without Rg1. Expression levels of α-smooth muscle actin (SMA), fibronectin and collagen type Iα1 were determined by reverse transcription polymerase chain reaction, Western blot and immunofluorescent staining. TGF-β1 signaling molecules, including Smad2/3, extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 were analyzed by Western blotting. Transcription factors involved with TGF-β1 signaling, nuclear factor (NF)-κB and activator protein 1 (AP-1) were also assessed by Western blot. The cytotoxic effect of Rg1 was measured by an established viability assay. The mRNA and protein expression levels of α-SMA, fibronectin and collagen type Iα1 were increased in TGF-β1-induced NPDFs. Rg1 inhibited these effects. The inhibitory molecular mechanism of Rg1 was involved in the ERK pathway. Rg1 inhibited the transcription factor activation of AP-1. Rg1 itself was not cytotoxic. The ginsenoside Rg1 has inhibitory effects on myofibroblast differentiation and ECM production. The inhibitory mechanism of Rg1 is involved with the ERK and AP-1 signaling pathways. Rg1 may be useful as an inhibitor of ECM deposition, and has potential to be used as a novel treatment option for nasal polyps.

Effect of [6]-gingerol on myofibroblast differentiation in transforming growth factor beta 1-induced nasal polyp-derived fibroblasts

BACKGROUND

[6]-Gingerol is one of the major pungent principles of ginger and has diverse effects, including anti-inflammatory, and antioxidative effects. Reactive oxygen species (ROS) are released during the phenotypic transformation of fibroblasts to myofibroblasts, a process that is involved in the growth of nasal polyps by inducing extracellular matrix (ECM) accumulation. The purpose of this study was to determine the effect of [6]-gingerol on myofibroblast differentiation and collagen production of nasal polyp-derived fibroblasts (NPDFs) and to determine if the effect of [6]-gingerol is linked to an antioxidant effect.

METHODS

NPDFs were incubated and treated with transforming growth factor (TGF) beta 1. The ROS generated by NPDFs were determined using 2″,7″-dichlorfluorescein-diacetate. The fluorescence was captured by a fluorescent microscope and measured using a fluorometer. The expression of alpha-smooth muscle actin (SMA) and collagen type IV mRNA was determined by a reverse transcription-polymerase chain reaction, and the expression of α-SMA protein and pSmad2/3 was determined by immunofluorescence microscopy and or Western blotting. The amount of total soluble collagen production was analyzed by the SirCol collagen dye-binding assay.

RESULTS

TGF-beta 1 stimulation increased ROS production by NPDFs. [6]-Gingerol decreased the production of ROS in TGF-beta 1-induced NPDFs. Myofibroblast differentiation, collagen production, and phosphorylation of Smad2/3 were prevented by [6]-gingerol and inhibition of ROS generation with antioxidant such as diphenyliodonium, N-acetylcysteine, and ebselen.

CONCLUSION

These results suggest the possibility that [6]-gingerol may play an important role in inhibiting the production of the ECM in the development of nasal polyps through an antioxidant effect.

Effect of Simvastatin on Transforming Growth Factor Beta-1–Induced Myofibroblast Differentiation and Collagen Production in Nasal Polyp-Derived Fibroblasts

Background

Statins are the most commonly prescribed drugs for the treatment of hypercholesterolemia. Statins exert not only lipid-lowering but also other cellular effects, including antifibrotic properties. The purpose of this study was to determine the effect of simvastatin on transforming growth factor (TGF)-beta-1–induced myofibroblast differentiation and collagen production in nasal polyp-derived fibroblasts (NPDFs) and to verify the mechanism of the effect of simvastatin in TGF-beta-1–induced myofibroblast differentiation in NPDFs.

Methods

NPDFs were pretreated with simvastatin with or without mevalonate or Y-27643 for 2 hours before induction by TGF-beta-1. The expression of alpha-smooth muscle actin (SMA) and collagen type IV mRNA was determined by a reverse transcription-polymerase chain reaction, and the expression of alpha-SMA protein was determined by immunofluorescent cytochemical staining. Total soluble collagen production was analyzed by the SirCol collagen dye-binding assay (Biocolor, Belfast, U.K.). Phosphorylation of Smad 2/3 was evaluated by Western blot analysis.

Results

In TGF-beta-1–induced NPDFs, simvastatin significantly inhibited the expressions of α-SMA and collagen type IV mRNA and reduced alpha-SMA and collagen protein levels. Pretreatment with mevalonate reversed the effect of simvastatin. The expression of alpha-SMA mRNA and protein was significantly decreased by pretreatment with Y-27632. The TGF-beta-1–induced expression of pSmad 2/3 protein was notably decreased by pretreatment with simvastatin.

Conclusion

We showed that simvastatin inhibits TGF-beta-1–induced myofibroblast differentiation (expression of alpha-SMA) and collagen production in NPDFs and Rho/Rock and TGF-β/Smad signaling is involved as an underlying mechanism. The results of our study suggest that simvastatin is a possible candidate for the suppression of nasal polyp formation.

Effects of nonsteroidal anti-inflammatory drugs on Helicobacter pylori-infected gastric mucosae of mice: apoptosis, cell proliferation, and inflammatory activity

Helicobacter pylori and nonsteroidal anti-inflammatory drugs (NSAIDs) are two well-known important causative factors of gastric damage. While H. pylori increases apoptosis and the proliferation of gastric epithelial cells and is an important factor in peptic ulcer and gastric cancer, NSAIDs induce cell apoptosis and have antineoplastic effects. We investigated the effects of NSAIDs (a nonselective cyclooxygenase [COX] inhibitor [indomethacin] and a selective COX-2 inhibitor [NS-398]) on the apoptosis and proliferation of gastric epithelial cells and gastric inflammation in H. pylori-infected mice. C57BL/6 mice were sacrificed 8 weeks after H. pylori SS1 inoculation. Indomethacin (2 mg/kg) or NS-398 (10 mg/kg) was administered subcutaneously once daily for 10 days before sacrifice. The following were assessed: gastric inflammatory activity, gastric COX protein expression by Western blotting; gastric prostaglandin E(2) levels by enzyme immunoassay, apoptosis by terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling, and cell proliferation by Ki67 immunostaining. Compared to the controls, H. pylori infection and/or NSAID treatment increased COX-1 and COX-2 protein expression. Gastric prostaglandin E(2) levels, apoptotic index, cell proliferation index, neutrophil activity, and the degree of chronic inflammation were all increased by H. pylori infection, and these effects were significantly decreased by indomethacin treatment. However, NS-398 treatment after H. pylori infection did not induce a significant reduction, although it did result in a tendency to decrease. These results show that NSAIDs can reverse the increased apoptosis and proliferation of epithelial cells and inflammatory activity in the stomachs of H. pylori-infected mice and that, like COX-2 activation, COX-1 induction contributes to the change of gastric mucosal cell turnover and inflammation induced by H. pylori infection.

Emergence of YMDD motif mutant of hepatitis B virus during short-term lamivudine therapy in South Korea

BACKGROUND/AIMS

The emergence of a YMDD mutant resistant to lamivudine therapy has been reported in patients with hepatitis B treated with long-term lamivudine therapy. However, it is not well known whether the YMDD mutant could be detected early in lamivudine therapy in hepatitis B virus (HBV) endemic areas. The aim of this study was to investigate the emergence of the YMDD mutant during short-term lamivudine therapy in South Korea.

METHODS

We prospectively investigated the emergence of the YMDD mutant by the nested PCR assay using restriction fragment length polymorphism in 28 patients with chronic hepatitis B who were treated with 100 mg of lamivudine daily for 12 weeks.

RESULTS

The YMDD mutant was detected in 17 (60.7%) out of 28 patients at week 12, and the only type of mutation found was the YIDD mutation. When we carried out the nested PCR serially in five patients, YIDD mutants were detected as early as 2 weeks by the nested PCR assay. The nested PCR results were in concordance with DNA sequencing in one patient's serial samples.

CONCLUSIONS

YMDD mutants in HBV were detected within a few weeks during lamivudine therapy in South Korea, which suggests that the YMDD mutant may exist even before lamivudine therapy in HBV endemic areas.

An ischemic skin lesion after chemoembolization of the right internal mammary artery in a patient with hepatocellular carcinoma

A huge nodular hepatocellular carcinoma located at the anterior superior portion of the left lobe in a patient with hepatocellular carcinoma was treated with transcatheter arterial chemoembolization through the left hepatic artery. Three months later, however, there was a re-elevation of the serum alpha-fetoprotein level and evidence of a marginal recurrence at the left side of the previously embolized tumor was noted on the postembolization computed tomographic scan. Although the hepatic artery was intact in the second hepatic arteriography, we found that the right internal mammary artery was feeding the recurred hepatocellular carcinoma. This internal mammary artery was successfully treated with Lipiodol-transcatheter arterial chemoembolization. However, an ischemic lesion occurred in the skin of the anterior chest and abdominal wall several days after internal mammary artery embolization. We report here a very rare case of ischemic skin lesion on the anterior chest and abdominal wall following transcatheter arterial chemoembolization of the right internal mammary artery. This internal mammary artery was embolized because it had developed a collateral tumor feeding vessel following the initial chemoembolization of a hepatocellular carcinoma.

Oxidative stress effect on the activation of hepatic stellate cells

Collagen is the most excessive extracellular matrix protein in hepatic fibrosis. Activated, but not quiescent, hepatic stellate cells (HSCs) have a high level of collagen and a smooth muscle actin (alpha SMA) expression. HSCs play a key role in the pathogenesis of hepatic fibrosis. We analyzed a mechanism leading to HSC activation by evaluating the role of oxidative stress and the expression of NFkB. In vitro study HSCs were proliferated (PCNA:2% vs 68%) and activated (alpha SMA: 5% vs 78%) by ascorbate/FeSO4, and HSCs activated by type I collagen were blocked (PCNA: 97% vs 4%, a SMA: 86% vs 9%) by a-tocopherol. In vivo study means of a SMA positive cells in liver at 400 x HPF were 48.3+/-5.2 and 15.2+/-1.8 and [3H]thymidine uptake of HSC was 529.2+/-284.8 cpm and 223.0+/-86.3 cpm in control and a-tocopherol treated group respectively at 32 hours after CCl4 injection. Nuclear extracts from activated, but not from quiescent, HSCs formed a complex with the NFkB cognate oligonucleotidesand alpha-tocopherol inhibited this bindings. This study indicates that oxidative stress plays an essential role through the induction of NFkB on HSC activation.

Local radiotherapy for unresectable hepatocellular carcinoma patients who failed with transcatheter arterial chemoembolization

PURPOSE

The purpose of this study was to investigate the efficacy of local radiotherapy (RT) as a salvage treatment for unresectable hepatocellular carcinoma (HCC) patients who failed with transcatheter arterial chemoembolization (TACE).

METHODS AND MATERIALS

Patients with unresectable HCC who had been treated with and eventually failed with TACE were eligible. The judgment of TACE failure was based on incomplete tumor filling of lipiodol-adriamycin mixture on either angiography or computed tomography (CT) scan. From January 1993 to December 1997, 27 patients were entered into this study. They had UICC Stage III (17) or IVA (10) disease, with a mean tumor size of 7.2 +/- 2.9 cm. Local RT was done, with a mean tumor dose of 51.8 +/- 7.9 Gy, in daily 1.8-Gy fractions using a 10- or 6-MV linear accelerator. Survival was calculated from both the diagnosis and the start of RT using the Kaplan-Meier method.

RESULTS

An objective response was observed in 16 of 24 patients (66.7%) including 1 CR. Intrahepatic metastasis was noted outside the RT field in 10 patients (37.0%). Extrahepatic distant metastasis occurred in 4 patients. Survival rates at 1, 2, and 3 years were 85. 2%, 58.1%, and 33.2%, respectively, from the diagnosis and 55.9%, 35. 7%, and 21.4%, respectively, from the start of RT. The median survivals were 26 months from the diagnosis and 14 months from the start of RT. Acute toxicity involved alteration in liver function test (13 patients) and thrombocytopenia (2 patients). Subacute and chronic toxicity involved gastroduodenal ulcer (3 patients) and duodenitis (2 patients). There was no treatment-related death.

CONCLUSION

In unresectable HCC patients who failed with TACE, local RT induced a substantial tumor response of 66.7%, with a 3-year survival rate of 21.4% and a median survival time of 14 months. Toxicity was significant but manageable. Although we do not know if there is survival benefit through this treatment, local RT in these patients seems to be valuable as a salvage for TACE-failed HCC.

Association between hepatitis B virus infection and HLA-DR type in Korea

Although the mechanism of susceptibility to chronic persistent hepatitis B virus (HBV) infection is not well clarified, immunogenetic factors of the host may have a role. Recently, a strong association between HLA-DR13 and the self-limited course of HBV infection has been reported. To determine whether the elimination of HBV is related to a particular HLA allele, we studied the HBV markers and HLA-DR phenotypes of 1,272 Koreans who had visited Yonsei University Medical Center for renal transplantation. They included 330 renal transplant donors. Subjects were categorized into 3 different groups: the "Unexposed Group" (UE; n = 946) with negative HBV markers, the "Chronic Carrier Group" (CC; n = 83), who were hepatitis B surface antigen (HBsAg)-positive, and the "Spontaneously Cleared Group" (SC; n = 243), who were HBsAg-negative with antibodies to HBsAg (anti-HBs) and hepatitis B core antigen (anti-HBc). HLA-DR4 was the most common type in all groups. HLA-DR6 was significantly more frequent in 69 of 243 subjects with SC (28. 4%) than in 8 of 83 subjects with CC (9.6%) (P <.001; relative risk [RR] = 3.72). HLA-DR9 was significantly more frequent in CC than in SC (P <.001; RR = 0.33). HLA-DR13 showed a stronger association with the clearance of HBV than the other HLA-DR6 subgroup. The distribution of HLA-DR phenotypes was similar regardless of renal disease. Our data indicate that HLA-DR6, especially HLA-DR13, is one of the host factors, which influences the immune response to HBV, and may be associated with self-elimination of HBV in Koreans.

Endoscopic snare resection for tumors of the ampulla of Vater

Though surgical resection has been the traditional treatment for tumors of the ampulla of Vater, endoscopic maneuvers such as snare resection, laser photodestruction and electrofulguration have recently been introduced to avoid operation-related morbidity and mortality. From 1994 to 1996, 6 patients with ampullary tumor were managed by endoscopic snare resection and regularly followed. Endoscopic snare resection of the ampullary tumor was technically feasible in all patients and each procedure was performed in a single session. Histologic diagnoses of the resected specimens were adenoma in 4 patients and adenoma with coexistent adenocarcinoma in 2 patients. Resection margins were negative in all patients except 1 with coexistent adenocarcinoma and a radical pancreaticoduodenectomy was performed in that case. For the other patient with adenocarcinoma foci, no further treatment was persued since he was 72-year-old and refused operation. Acute pancreatitis developed in 2 patients after endoscopic therapy, but was resolved with conservative management. There was no procedure-related death. Surveillance duodenoscopy performed at 1 and 6 months after endoscopic resection revealed no evidence of recurrent tumor in 4 patients with adenoma. Among them, 3 patients are alive without evidence of recurrence at 16-37 months after resection, but 1 patient was lost after 9 months of follow-up. The patient with adenocarcinoma in whom a pancreaticoduodenectomy was performed, has been alive without recurrence for 12 months. Oral 5-fluorouracil was administered for the other patient with adenocarcinoma foci. Though he experienced local recurrence at 13 months after the procedure, he has been alive for 28 months after resection. In conclusion, endoscopic snare resection may be applied as a viable alternative to surgery in selected patients with small ampullary tumors.

Tissue plasminogen activator and plasminogen activator inhibitor-1 in human choledochal bile

Fibrinolytic properties have been detected in animal and human gallbladder (GB) bile. Plasminogen activator inhibitor-1 (PAI-1) has been reported in greater concentration in GB stone bile and may be a nucleating factor in the pathogenesis of GB stone formation. It is unknown whether or not human choledochal bile has similar properties, which could have a role in choledocholithiasis. The aims of this study were to determine the presence of fibrinolytic properties of human choledochal bile and to compare those properties among normal, acalculous, and calculous-infected choledochal bile. Tissue plasminogen activator (t-PA) and PAI-1 of choledochal bile were measured by enzyme linked immunosorbent assay in patients with cholangitis due to acalculous bile duct obstructions (n = 9), choledocholithiasis with cholangitis (n = 20), and normal bile (n = 7). The t-PA concentration of choledochal bile was no different among the three groups (acalculous-infected bile, median 4.61 ng/ml, and calculous-infected bile, 4.61 ng/ml, versus normal bile, 7.33 ng/ml). PAI-1 was detected in choledochal bile in significantly greater concentrations in patients with acalculous cholangitis due to bile duct obstructions and choledocholithiasis with cholangitis (acalculous-infected bile, median 0.36 ng/ml, and calculous-infected bile, 0.1 ng/ml, versus normal bile, 0.02 ng/ml, p < 0.05), but the bile concentration of PAI-1 was no different between the acalculous and calculous-infected choledochal bile. Human choledochal bile possesses t-PA and PAI-1. PAI-1 was present in greater concentrations in both acalculous and calculous-infected choledochal bile. Increased levels of PAI-1 may be an epiphenomenon of cholangitis rather than a factor in the pathogenesis of choledocholithiasis.

A novel primer-extension assay for the detection of a G to A mutation in the distal precore region of hepatitis B virus DNA

The roles of genetic heterogeneity of the hepatitis B virus (HBV) precore gene in the pathogenesis of HBV infection are unclear. Various methods have been used to detect nucleotide (nt) 1896 precore mutants. We established a new primer-extension assay to facilitate the detection of these mutants. This assay is based upon the fact that there is no adenine in the distal precore region of wild-type HBV. Polymerase chain reaction (PCR)-amplified template DNA was denatured and annealed to the [gamma-32P]-labelled primer. During primer extension in the presence of DNA polymerase and dCTP, dGTP, dTTP and ddATP, the reaction terminates if there is a nucleotide A. When mixtures of different ratios of wild-type and nt 1896 precore mutants were analysed in the primer-extension assay, correlation between the percentage known amounts and the percentage measured amounts of nt 1896 precore mutants was excellent (r2=0. 9669). When the primer-extension assay and direct sequencing were compared in hepatitis B e antigen (HBeAg)-positive and -negative chronic active hepatitis B patients, the primer-extension assay detected a greater number of nt 1896 precore mutants than direct sequencing and thus most HBV infections were found to be mixed infections. In conclusion, the primer-extension assay is a reliable and sensitive method for the detection of nt 1896 precore mutants.

Villous adenoma of the bile ducts: a case report and a review of the reported cases in Korea

Villous adenomas are benign epithelial lesions with malignant potential which can occur at any site in the gastrointestinal tract. They are usually encountered in the rectum and colon, less frequently in the small bowel and very rarely in the biliary trees. Nine cases of bile duct villous adenomas have been reported in the literature. However, 4 cases of bile duct villous adenomas have been reported in the Korean literature. Recently, we experienced a case of villous adenoma in the common hepatic duct in a 77-year-old man presenting with obstructive jaundice in which preoperative histologic diagnosis of villous adenoma played a critical role in managing this patient. Herein, we present a case report of bile duct villous adenoma and a review of the reported cases in Korea to help define and manage this rare disease entity in the bile ducts. In addition, confusing nomenclature of bile duct adenomas is discussed.

Combined transcatheter arterial chemoembolization and local radiotherapy of unresectable hepatocellular carcinoma

PURPOSE

The best prognosis in hepatocellular carcinoma (HCC) can be achieved with surgical resection; however, the number of resected cases are limited due to advanced lesions or associated liver disease. The purpose of this study was to investigate the efficacy and toxicity of a prospective trial of combined transcatheter arterial chemoembolization (TACE) and local radiotherapy (RT) in unresectable HCC.

METHODS AND MATERIALS

Patients with histologically proven unresectable HCC due to either advanced lesions or associated cirrhosis were eligible. From March 1992 to August 1994, 30 patients were entered into this study. TACE was performed with Lipiodol (5 ml) and doxorubicin (Adriamycin ; 50 mg), followed by gelatin sponge particle (Gelfoam) embolization. Local RT was started within 7-10 days following TACE. Mean tumor dose was 44.0+/-9.3 Gy in daily 1.8 Gy fractions. Response was assessed by computerized tomography (CT) scan 4-6 weeks following completion of the treatment and then at 1-3-month intervals. Survival was calculated from the start of TACE using the Kaplan-Meier method.

RESULTS

An objective response was observed in 19 patients, giving a response rate of 63.3%. Distant metastasis occurred in 10 patients, with 8 in the lung only and 2 in both lung and bone. Survival rates at 1, 2, and 3 years were 67%, 33.3%, and 22.2%, respectively. Median survival was 17 months. There were 6 patients surviving more than 3 years. Toxicity included transient elevation of liver function tests in all patients, fever in 20, thrombocytopenia in 4, and nausea and vomiting in 1. There was no treatment-related death.

CONCLUSION

Combined TACE and local RT is feasible and tolerable. It gives a 63.3% response rate with median survival of 17 months. We feel that this regimen would be a new promising modality in unresectable HCC. Further study is required to compare the therapeutic efficacy of this regimen to TACE alone.

Comparative study of bentiromide test and endoscopic retrograde pancreatography in patients with chronic pancreatitis

We performed a bentiromide test in 25 patients with chronic pancreatitis and 7 normal controls to evaluate pancreatic exocrine function, and compared the test results of patients with their endoscopic retrograde pancreatography(ERP) findings. The cumulative 6-hour recovery rate of para-aminobenzoic acid(PABA) in the urine was significantly lower in patients with chronic pancreatitis(55.8 +/- 24.2%) than in controls(82.0 +/- 10.0%). Among 25 patients with chronic pancreatitis, however, 7 patients showed normal recovery rates of PABA. Pancreatograms of the patients represented 4 mild changes, 5 moderate changes, and 16 marked changes. The average 6-hour recovery rates of PABA of the groups were 56.9 +/- 21.6%, 78.4 +/- 10.5%, and 47.2 +/- 23.7%, respectively. Urinary PABA recovery rates were found subnormal as follows: 3(75%) in the mild changes group; 1(20%) in the moderate changes group; and 14(87.5%) in the marked changes group. We found hardly any correlation between the degree of functional impairment and the changes noted by ERP. These findings suggest that both the pancreatic function test and morphologic study are required to evaluate the degree of functional impairment in patients with chronic pancreatitis.

Comparison of the hemostatic effect of endoscopic injection with fibrin glue and hypertonic saline-epinephrine for peptic ulcer bleeding: a prospective randomized trial

BACKGROUND AND STUDY AIMS

Although endoscopic injection therapy using various agents has been considered the least expensive and most effective technique in obtaining hemostasis in peptic ulcer bleeding, most of these agents induce tissue necrosis or degeneration. Theoretically the injection of fibrin glue (FG) to halt peptic ulcer bleeding may be safer than the use of other agents, but randomized clinical trials to compare the efficacy of FG and other agents are rare. The aim of this study was to compare the hemostatic efficacy between FG and hypertonic saline-epinephrine (HSE) in peptic ulcer bleeding.

PATIENTS AND METHODS

From March 1992 to December 1993 we conducted a prospective randomized trial in 127 patients with peptic ulcer bleeding, in whom a visible vessel or active bleeding was identified. Patients were randomized into two groups, an FG group comprising 64 patients who received FG injections, and an HSE group, comprising 63 patients who received HSE injections.

RESULTS

The two groups were comparable with regard to age, sex, bleeding focus and bleeding stigma. Permanent hemostasis using only endoscopic treatment was achieved in 59 cases (92.2 %) in the FG group and in 54 cases (85.7 %) in the HSE group. Rebleeding occurred in seven cases (10.9%) in the FG group and in 14 cases (22.2%) in the HSE group (P=0.087); emergency surgery was undertaken in four (6.3%) and seven cases (11.1%), respectively (P = 0.33); death occurred in one case (1.6%) and four cases (6.3%), respectively (P = 0.165).

CONCLUSIONS

These results suggest that endoscopic injection of FG is an effective method in the control of peptic ulcer bleeding. However, even though there is a strong trend supporting the hypothesis that fibrin glue is superior to HSE, no statistically significant differences are noted. A trial involving larger numbers may produce a positive result.

Peritoneoscopic liver biopsy findings in asymptomatic chronic HBsAg carriers with normal liver function tests and no hepatomegaly

Asymptomatic chronic HBsAg carriers with normal liver function tests are, in general regarded as having no liver pathology. Most of the histologic findings in asymptomatic chronic carriers have been reported from areas with low incidence of Hepatitis B virus (HBV) infection, such as North America and Western Europe. It is well known that there are many differences in HBV infection between low and high endemic areas, but there have been few reports on the histologic findings of asymptomatic chronic HBsAg carriers from endemic areas. The present study was undertaken in Korea which is one of the endemic areas for HBV infection and was designed to assess the prevalence of chronic liver disease by peritoneoscopic liver biopsy among asymptomatic chronic HBsAg carriers and to make a basis for the follow-up of asymptomatic chronic HBsAg carriers according to the results obtained. One hundred and ten asymptomatic HBsAg-positive carriers with normal liver function tests and no hepatomegaly were included in the study. Final diagnosis by peritoneoscopic liver biopsy revealed that of the 110 asymptomatic carriers only 27 (24.5%) had a histologically normal liver, while 51 (46.4%) had chronic liver diseases, and the remaining 32 (29.1%) had nonspecific histologic abnormalities (nonspecific reactive changes in 18 cases, cholestasis in 6 cases, and fatty change in 8 cases). Of the 51 patients with chronic liver diseases, 3 had liver cirrhosis, 4 chronic active hepatitis with cirrhosis, 11 chronic active hepatitis and 33 chronic persistent hepatitis. The frequency of liver cirrhosis and chronic active hepatitis with cirrhosis was significantly high in the over 30 years of age group (12.1%) than in the under 30 years of age group (0%; p = 0.011 by Fisher's exact test). In conclusion, 46.4% of the Korean asymptomatic chronic HBsAg carriers with normal liver function tests and no hepatomegaly had chronic liver disease. This finding contrasted with reports from low incidence areas of HBV infection. Our results suggest that in endemic areas, a liver biopsy should be considered to assess the status of liver disease in asymptomatic chronic HBsAg carriers even if liver function tests are normal and hepatomegaly is absent, and the result can be used as a basis for the follow-up of each asymptomatic chronic HBsAg carriers.

Adjuvant effect of polyadenylic.polyuridylic acid on antibody production of recombinant hepatitis B surface antigen in mice

The adjuvant effect of polyadenylic.polyuridylic acid [poly(A).poly(U)] on antibody production against recombinant hepatitis B surface antigen (rHBsAg) was investigated. Immunization of adult Balb/c mice with rHBsAg plus poly(A).poly(U) elicited significantly higher antibody responses than immunization of mice immunized with rHBsAg alone. Such an adjuvant effect was evident even in mice sensitized with subimmunogenic doses of the antigen.

Duodenal ectopic pancreas complicated by chronic pancreatitis and pseudocyst formation--a case report

Ectopic pancreas is no longer a rare clinical condition, but its unusual clinical manifestations, locations or complications are of clinical interest. We experienced a case (a 48 year-old male patient) of duodenal ectopic pancreas complicated by chronic pancreatitis and pseudocyst formation of which preoperative imaging findings mimicked a large duodenal submucosal tumor with cystic degeneration such as a leiomyosarcoma. Simultaneous chronic pancreatitis was also demonstrated in the isotopic pancreas of the patient postoperatively. Herein we report a rare clinical condition occurring in an ectopic pancreas with a brief review of the literature.

Efficacy of polyadenylic.polyuridylic acid in the treatment of chronic active hepatitis B

In order to assess whether polyadenylic.polyuridylic acid [poly(A).poly(U)] can be used as a new therapeutic agent for the treatment of chronic hepatitis B, 19 patients with histologically proven chronic active hepatitis B were injected intravenously with 100-150 mg of poly(A).poly(U) weekly for six weeks. Changes in alanine aminotransferase (ALT) levels, 2',5'-oligoadenylate synthetase (2'.5'-AS) activities and HBV markers were sequentially checked during and after treatments. Serum ALT levels were decreased gradually and 2'.5'-AS activities were significantly increased after initiation of poly(A).poly(U) injections. At the end of this trial (24th week) we have observed the normalizations of elevated ALT levels in 14 (73.7%), negative conversion of HBeAg in 11 (57.9%) and loss of HBV-DNA in 12 out of 19 patients (63.1%). Complete responses which had both normalization of ALT levels and negative conversion of HBeAg were noted in 11 patients (57.9%) and partial responses showing either normalization of ALT levels or negative conversion of HBeAg alone were in four out of 19 patients (21.1%). No notable adverse effects were observed during the treatments and follow-up period. It can be concluded that poly(A).poly(U) seems to be effective in the treatment of chronic active hepatitis B and has an advantage of being free of significant side effects.

Effect of anticancer drugs and desferrioxamine in combination with radiation on hepatoma cell lines

Several anticancer chemotherapeutic agents (5-fluorouracil, adriamycin and cisplatinum) and desferrioxamine, an iron chelator, were tested with regard to cytotoxicity and to the combined effect on radiation induced cell killing using two human hepatoma cell lines (HepG2 and PLC/PRF/5). Survival fractions were measured by quantitative colorimetric assay (MTT assay) and dose-response curves were plotted. MTT assay could be successfully used in the assessment of radiosensitivity in addition to chemosensitivity, because a good linear relationship between optical densities and cell numbers was observed and cells approached exponential growth for the first 7 days of culture when 5 x 10(3) or less cells were inoculated per well in our study. Steepness of the final slope (D0), width of the shoulder (D0) and the extrapolation number (n) of radiation survival curves were 1061.72 rad, 226.43 rad and 1.25 respectively in HepG2 and 1091.38 rad, 268.42 rad and 1.29 respectively in PLC/PRF/5. After combining anticancer chemotherapeutic agents and desferrioxamine with radiation, the widths of the shoulders were decreased whereas sensitizer enhancement ratios were increased as the concentration of drugs increased in both cell lines. These results suggest that neither anticancer chemotherapeutic agents nor desferrioxamine enhance cell killing induced by radiation alone, but suggested the possibility that they inhibit the repair of radiation damage.

Histologic study of chronic active hepatitis C; comparison with chronic active hepatitis B

Reports on the histologic findings of chronic active hepatitis C (CAH-C) have been rare, and the characteristic histologic findings of CAH-C have been not yet determined. To compare the differences in the histologic findings between CAH-C and chronic active hepatitis B (CAH-B) group, we analyzed the histologic findings of 19 patients with CAH-C, who had positive tests for HCV-antibody by EIA, and 19 patients with CAH-B who had negative tests for HCV-antibody but positive tests for HBsAg by RIA. Histologic features were analyzed between the CAH-C and CAH-B groups using a scoring system which is modified from Knodell's histologic activity index-looking at portal inflammation, periportal necroinflammation, portal fibrosis, focal necrosis, regeneration, polyploid nuclear change, sinusoidal lymphocytic reaction and fatty change. Portal inflammatory cell infiltrations with prominent lymphocytes and follicular arrangement were more frequent in the CAH-C group (10 of 19 cases) than in the CAH-B group (5 of 19 cases). Severe sinusoidal lymphocytic reactions were also more prominent in the CAH-C group (11 of 19 cases) than in the CAH-B group (6 of 19 cases). However, periportal necroinflammation, portal fibrosis, focal hepatic necrosis, regeneration and polyploid nuclear changes were more prominent in the CAH-B group than in the CAH-C group. In conclusion, follicular portal inflammation and severe sinusoidal lymphocytic reactions were common histologic findings in serologically proven CAH-C when compared to CAH-B.

Gastric varices: diagnosis with duplex Doppler ultrasonography--a case report

The diagnosis of gastric varices may be difficult due to their anatomic location and morphology. In this abstract we describe a case of gastric varices, of which a duplex Doppler sonography was useful in the diagnosis, that was initially suggested as submucosal tumor of the stomach by barium studies and endoscopy.

Percutaneous fine needle aspiration biopsy of pancreatic cancer guided by ultrasonography

Fine needle aspiration biopsy guided by ultrasonography was performed in 39 patients with pancreatic cancer to evaluate the value of the technique for establishing a proved histologic diagnosis. Aspirated material suitable for cytologic evaluation of smear preparation was obtained from 33 patients (84.6%). Among the 33 patients, cytologic diagnosis of pancreatic cancer was possible in 28 patients (84.9%). There was mild abdominal pain only in one patient (2.6%). In conclusion, percutaneous fine needle aspiration biopsy guided by ultrasonography proved to be a safe and useful method for histologic diagnosis of pancreatic cancer.

The normal endoscopic pancreatogram in Koreans

The establishment of endoscopic retrograde cholangiopancreatography (ERCP) as a valuable procedure in diagnostic evaluation of patients with suspected pancreatic disease requires the precise delineation of normal pancreatography. Therefore, to establish normal standards in Koreans of pancreatic ductal morphology, such as course, diameter and length including the shape of the ampulla and the success rate of the ERCP procedure, we analyzed the pancreatograms of persons with proven normal pancreatic status. Of the 449 cases showing normal duodenal papilla, the hemispherical type of shape (49.7%) was the most common, followed by the papillary type (36.5%) and flat type (13.8%) in order of frequency. The success rate of ERCP procedure (1,020 cases) was 95.3%, and the selective success rate was 90.9% for the pancreatic duct and 79.3% for the biliary tree. In the course of the pancreatic duct (286 cases), the ascending type of extension (51.7%) was the most common followed by the sigmoid type (25.2%), horizontal type (22.4%) and descending type (0.7%). The diameter of the pancreatic duct was 3.3 +/- 0.8 mm in the head, 2.4 +/- 0.5 mm in the body and 1.5 +/- 0.5 mm in the tail portion, and there was a tendency that the diameter of the pancreatic duct progressively increased with age. The length of the pancreatic duct was 17.5 +/- 2.8 cm. In conclusion we hope that, by utilizing these various parameters of the normal endoscopic retrograde pancreatogram, precise diagnosis will be possible.

Analysis of cases of nonvisualized gallbladder by ultrasonography

To define the significance of nonvisualization of the gallbladder by ultrasonography, we studied follow-up data on 31 cases in which the gallbladder could not be identified despite adequate fasting. Thirty one cases of gallbladder disease included 15 cases of chronic cholecystitis due to cholelithiasis (13 cases) and choledocholithiasis (2 cases), 4 cases of cholelithiasis which were not surgerized, and 3 cases of cancer. There were 4 cases of diagnostic error in which gallbladder nonvisualization occurred despite a demonstrable lumen. The etiology of disease was not determined in the 5 remaining cases. Therefore 22 of 26 cases were found to have diseased gallbladders. The resasons for nonvisualization of the gallbladder by ultrasonography in the 19 cases which underwent surgicl exploration were: 17 cases due to chronic cholecystitis with cholelithiasis (13 cases), choledocholithiasis (2 cases) and cancer (2 cases), obliteration of the lumen due to cancer of the gallbladder in one cases, and technical error due to an unusual location of the gallbladder in one case. The mechanisms of diagnostic error in 4 cases seemed technical error due to an unusual location of the gallbladder in 3 cases and the obscured gallbladder by intestinal gas in one case. In conclusion, we feel that careful examination should be done to detect a gallbladder located unusually or obscured by intestinal gas in order to decrease the rate of diagnostic error when the gallbladder is not visualized by ultrasonography. Also, we recommend an oral cholecystography or ERCP for ultrasonic nonvisualized gallbladder.

A study of 122 cases of pancreatic cancer diagnosed by endoscopic retrograde cholangiopancreatography (ERCP)

ERCP is a highly accurate and specific method for evaluating patients with suspected pancreatic disease. Its diagnostic significance of specific pancreatographic signs is of even greater importance. We reviewed 122 cases of pancreatic cancer who were done ERCP, at the Department of Internal Medicine, Yonsei University, College of Medicine between June 1973 and August 1983. The results were as follows: 1. The ages of 122 patients ranged from 27 to 76 with the majority in the 6th and the 7th decades. The male to female ratio was 2.49:1. 2. The success rate of cannulation into the orifice of the duodenal papilla in 122 cases was 97.5% (119/122), and the pancreatic duct was visualized in 91.0% (111/122). 3. Diagnostic accuracy of ERCP in pancreatic cancer was 96.4% (107/111) among cases in whom the pancreatic duct was visualized. 4. By ERCP the most common site of the lesion was head of pancreas (51.4%). 5. According to Fukumoto’s classification, the most common type was obstructive type (65.4%), followed by the stenosing type (29.0%), abnormal branching type (3.7%), and narrowing type (1.9%). 6. According to Takaki’s classification, Type I (obstruction or stenosis of the main pancreatic duct) was most common (85.6%), followed by Type III (pancreatic dilatation) (9.0%), Type IV (normal pancreatic duct) (3.6%), and Type II (obstruction of Wirsung’s duct or Santorini’s duct) (1.9%). 7. Of the 122 cases of pancreatic cancer, the bile duct was visualized in 55 and abnormalities, such as indentation (32.1%), stenosis (42.9%), and obstruction (25.0%) were found in 28. The locations of abnormal findings in the bile duct were distal (50.0%), middle (46.4%), and proximal (3.6%).